Isolation, structural characterization and bioactivities of polysaccharides and its derivatives from Auricularia-A review

Journal Pre-proof Isolation, structural characterization and bioactivities of polysaccharides and its derivatives from Auricularia-A review

Jingnan Miao, Joe M. Regenstein, Junqiang Qiu, Junqing Zhang, Xiaopo Zhang, Haixia Li, Hua Zhang, Zhenyu Wang PII:

S0141-8130(19)37412-4

DOI:

https://doi.org/10.1016/j.ijbiomac.2020.02.054

Reference:

BIOMAC 14671

To appear in:

International Journal of Biological Macromolecules

Received date:

12 September 2019

Revised date:

28 January 2020

Accepted date:

6 February 2020

Please cite this article as: J. Miao, J.M. Regenstein, J. Qiu, et al., Isolation, structural characterization and bioactivities of polysaccharides and its derivatives from AuriculariaA review, International Journal of Biological Macromolecules(2020), https://doi.org/ 10.1016/j.ijbiomac.2020.02.054

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© 2020 Published by Elsevier.

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Isolation, structural characterization and bioactivities of polysaccharides and its derivatives from Auricularia-A review Jingnan Miao,a,c,e Joe M. Regenstein,b Junqiang Qiu,a,c,e* Junqing Zhang,a,c,e* Xiaopo Zhang,a,c,e Haixia Li,a,c,e Hua Zhang,d* Zhenyu Wang,d School of Pharmacy, Hainan Medical University, Haikou, Hainan,

of

a.

570100, China,

Department of Food Science, Cornell University, Ithaca, NY

ro

b.

Hainan, 570100, China

Department of Food Science, School of Chemistry and Chemical

na

d.

re

Hainan Provincial Key Laboratory of R & D on Tropical Herbs, Haikou,

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c.

-p

14853-7201, USA

Engineering, Harbin Institute of Technology, Harbin, Heilongjiang,

e.

Jo ur

150010, China.

Key Laboratory of Tropical Translational Medicine of Ministry of

Education, Haikou, Hainan, 570100, China *Corresponding Author: E-mail: [email protected]; Fax: +86 898 31350616; Tel: +86 898 31350616; Haikou, Hainan, 570100, China.

Running Title: Polysaccharides and their derivatives from Auricularia

1

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Abstract Auricularia mushrooms are known for their bioactive compounds, mostly polysaccharides, which have numerous biological activities, such as

antioxidant,

antitumor,

immunomodulatory,

hyperlipidemic,

antidiabetic, anticoagulant and hepatoprotective effects. Over the past

of

decades, there has been a consistent focus on the isolation, chemical properties and bioactivities of polysaccharides from Auricularia. This

ro

review will cover what is known about Auricularia polysaccharides (AP)

-p

especially for several common species, including A. auricula-judae, A.

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auricula, A. polytricha, and A. cornea var. Li. The isolation and

lP

purifications, structural characterizations, chemical modifications, and

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biological activities of these AP and their derivatives will be discussed, thus to provide a foundation for the further investigation, production, and

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application of AP as functional foods and therapeutic agents. Keywords: Auricularia; Polysaccharides; Mushrooms; Wood ears; Jelly ears

2

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1. Introduction Auricularia mushrooms, also known as wood ears or jelly ears, are a group of mushrooms that form gelatinous fruiting body [1]. The Auricularia fruit body can be easily identified from its noticeably ear-like shape, and brown or black coloration. Almost all species of Auricularia

of

are widely distributed in tropical, subtropical, and temperate regions [2]. As the 4th most important mushroom genera, they have been widely

ro

collected, cultivated, and consumed for hundreds of years in many

-p

countries, including China, Thailand, Korea, Vietnam, Japan, and New

re

Zealand [3]. Auricularia fruiting body has been traditionally consumed as

lP

foods as well as herbal medicines for more than 1000 years in China [4].

na

As the largest producer of Auricularia, the annual output of China accounted for more than 90% of total productions in the world. auricula-judae

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Auricularia

(A.

auricula-judae)

and

Auricularia

polytricha (A. polytricha) are the main species cultivated, which are all around China, particularly in Heilongjiang, Jilin, Shanxi, Zhejiang, Yunnan, and Guangxi provinces. In 1978, 2 kinds of β-D-glucans (water-soluble glucan I and alkali-insoluble glucan II) were first isolated from the fruiting body of A. auricula-judae by extracting with saline (0.9% aqueous sodium chloride), their structural features and antitumor activities were shown [5-6]. The fruit body of Auricularia is rich in polysaccharides, and various 3

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bioactivities of these Auricularia polysaccharides (AP) have been reported, including antioxidant [7], antitumor [8], anticoagulant [9], immunomodulatory [10], and hepatoprotective activities [11]. To improve biological activities and expand applications, many AP derivatives have been developed including sulfated AP [12], carboxymethylated AP [13],

of

AP-polymer complexes [14], and AP-based nanoparticles [15]. These compounds are being consumed by the food, pharmaceutical, and industries

because

of

their

biodegradability

ro

chemical

and

-p

biocompatibility as well as good safety and bioactivity [16-18]. However,

re

the higher order structures of the AP and the relationships between

lP

bioactivity and chemical structure are still not clear.

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In this paper, research findings during the past decades have been summarized, including the extraction and purification techniques,

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modifications, structural characteristics, and biological activities. The aim is not only to give a comprehensive insight into extraction and purification techniques, chemical structures and biological activities, but also provide knowledge that will lead to more development and applications of AP, and stimulate interests in the relationships between their structural features and biological activities. 2. Extraction and isolation of AP AP have been extracted and isolated from Auricularia. In brief, the extraction steps start with washing the Auricularia fruiting body, oven 4

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drying or vacuum drying at ~50 - 60 ℃ for ~24 - 48 h and then grinding to powder (~250 - 850 μm) [7, 14, 16]. The particle size of the powder has an important role in the extraction efficiency of AP, because it not only determines the contact area between the powders and extraction solvents, but also influences the mass transfer kinetics and the access of

of

extraction solvents to the polysaccharides. The powders may be refluxed with petroleum ether, ethyl acetate, and/or methanol for 24 h to remove

ro

the lipophilic substances and other low-molecular weight (the weight

-p

average, MW) compounds [19]. Then, the dried Auricularia fruiting body

re

powders were usually extracted with distill or deionized water [6], low

lP

concentrations of NaOH [14, 20], HCl [21], ethanol aqueous solutions

na

[22] or NaCl solutions [10, 19] to obtain AP with different properties. Moreover, polyethylene glycol [23], formic acid [24], submerged cultures

Jo ur

[25] or solid-state fermentations [26] have also been reported to obtain AP. The extraction yields of AP using different solvents are very different. It was reported that the yields of AP using 70% ethanol solution, polyethylene glycol, and distilled water were 1.5, 25.8, and 32.2% [13, 22-23], respectively. The species and regions of AP have significant effects on the yields of polysaccharides. Research conducted on AP extractions from 4 different regions by Xu et al. [20] found that the yields of AP from A. auricula harvested in Shanxi and Heilongjiang provinces were highest, which were at 53 ± 1 and 50 ± 1% (Almost at the same 5

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level). And the second from Anhui province was 35 ± 1%. AP obtained from Zhejiang province had the lowest yield, which was 26 ± 1%. The non-extracted parts were removed by filtration or centrifugation. For alkaline or acid extraction, the resultant filtrate or supernatant should be neutralized using HCl or NaOH, then concentrated and dialyzed (nominal MW cutoff of 3500 Da) to obtain concentrated extracts. The extracts were

of

then precipitated with 95% ethanol (~1: 3 - 1: 5, v/v) at 4 ℃ for ~ 6 - 24 h,

obtain

higher

yields

of

AP

from

-p

To

ro

and centrifuged at ~1600 - 3200 g to obtain crude polysaccharides [20]. Auricularia,

many

re

environmentally-friendly extraction techniques have been used to

lP

promote the breakdown of the cell walls, including ultrasonic- [23],

na

microwave- [1], and pulsed electric field-assisted extractions [9], which can also shorten the processing time, lower solvent and energy

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consumption. These extraction techniques were believed to be inexpensive, environment-friendly, fast, and efficient. In addition, response surface methodology (RSM) has been widely used in optimizing the extracting conditions of polysaccharides from mushrooms. Li et al. [9] found the AP extracted using pulsed electric fields had better anticoagulant activity than using microwave and ultrasound. Extraction conditions, including the mesh size of A. auricula powders, solvents, solvent to raw material ratio, temperature, and time, all had significant effects on the extraction yields [23]. The extraction parameters for AP 6

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were optimized using RSM with the most favorable conditions being: water: raw material ratio (v/w), 28.0 mL/g; extraction temperature, 95.0 ℃; extraction time, 4.0 h; and water: raw material ratio (v/w), 38.8 mL/g; extraction temperature, 94.0 ℃; extraction time, 3.4 h [27-28]. As an environment-friendly solvent, polyethylene glycol (PEG) has been

design

was

used

to

enhance

the

of

used for increasing the extraction yield of AP. An orthogonal experiment extraction

efficiency

of

ro

ultrasound-assisted extraction of AP by Zhang et al [23]. The yield of AP

-p

was significantly improved, when the A. auricula was smashed into a

re

superfine powder (~13 - 48 μm). The optional extraction conditions of AP

lP

were: PEG: raw material ratio (v/w), 39.3 mL/g; extraction temperature,

25.8%

[23].

na

91.9 ℃; and extraction time, 32.4 min, under which, the yield reached The

microwave-,

pulsed

electric

field-,

and

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ultrasonic-assisted treatments might cause changes in conformations, intrinsic viscosities, particle sizes, molecular morphologies, MW, antioxidant activities of AP, but not in the main chemical structures [29-31]. The AP obtained using microwave had lower MW, higher contents of glucose, and better antioxidant activities, which indicated that the MW of AP may also be an important factor that influencing the antioxidant activities. 3. Purification and characterization of AP Following extraction, a combination of techniques should be used to 7

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remove proteins, phenolic compounds, monosaccharides, and other contaminants from the crude AP, including the Sevag method, ethanol precipitation, fractional precipitation, ion-exchange chromatography, gel filtration, and affinity chromatography [32-33]. Proteins are removed by treating with 1/5th volume of AP of Sevag reagent (butyl alcohol:

of

chloroform). The treatment should be repeated until there is no absorption at 269 nm [20]. Then the impurities are removed from the AP with precipitation.

The

separation

of

ro

ethanol

acidic

and

neutral

-p

polysaccharides can be achieved using quaternary ammonium salts or

re

cetyl pyridinium chloride, which is a simple and rapid method [34]. They

lP

can also be separated using ion-exchange cellulose chromatography,

na

including diethylaminoethyl (DEAE)-cellulose [1], DEAE-Toyo-pearl [34], and DEAE-Sepharose fast-flow columns [35]. The polysaccharides

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with different MW are usually separated initially using the precipitants, including ethanol, methanol, and acetone. These polysaccharides also are separated using gel chromatography, including Sephadex G, Sephacryl S, and Sepharose CL, which are usually employed after separation using ion-exchange cellulose chromatography. The multiple schemes for extractions and purifications of AP are shown in Fig. 1. Zhang et al. [36] reported that the separations of acidic and neutral AP were carried out with cetyl trimethyl ammonium bromide (CTAB). Anion-exchange chromatography on a DEAE-cellulose column was usually used for the 8

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separation of acidic and neutral AP [37]. The neutral and acidic AP could be successively eluted using distilled water or different concentrations of salt solutions, thus separated from the crude AP. A crude AP was purified using DEAE-cellulose 52 chromatography to give 5 fractions, named AAP I, AAP II, AAP III, AAP IV, and AAP V, which were eluted using

of

sodium chloride solutions (0, 0.1, 0.2, 0.3, 0.4, and 0.5 M). The main fraction (AAP IV) was further fractionated using a Sephadex G-200

ro

column, which led to a single polysaccharide peak [38]. Song et al. [8]

-p

reported that 3 polysaccharide components of AAP-1 (192 mg), AAP-2

re

(137 mg), AAP-3 (98 mg) were successfully separated from the crude AP

lP

(2 g) using high-speed counter-current chromatography (HSCCC) [8].

na

The MW of 3 polysaccharides was determined using high performance size-exclusion chromatography (HPSEC), which were 162, 259, and 483

Jo ur

kDa, respectively. The neutral polysaccharides from AP could be further separated into α-glucans (adsorbed fraction) and β-glucans (non-adsorbed fraction) using gel filtration and affinity chromatography [4]. In addition, HPSEC combined with multi angle laser light scattering detector and refractive index detector (HPSEC-MALLSD-RID) may be another useful analysis technique for AP, which could be used for measuring various polysaccharides with different MW as well as for obtaining aggregation information (rod, irregular coil or ball) of polysaccharides [39]. Large numbers of AP with various biological activities have been isolated, 9

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and the activities are significantly affected by the chemical structures and chain conformations of the polysaccharides, including intrinsic viscosities, monosaccharide compositions and sequences, MW, configurations of glycosidic linkages, types of glycosidic linkages, and positions of glycosidic linkages [34]. The schematic structures of AP are summarized

of

in Fig. 2. The AP with different monosaccharide constituents, MW, and chemical

ro

structures have been found. Their basic chemical structures have been

-p

characterized using spectral analysis, physicochemical analysis, chemical

re

analysis, and chromatography, including rheometer [18, 31], Zeta-sizer

lP

Nano instrument [16], thermal gravimetric analysis (TGA) [40], Fourier

na

transform infrared spectroscopy (FTIR) [41], gas chromatography (GC) [40, 42], gas chromatography-mass spectrometry (GC-MS) [43, 44],

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nuclear magnetic resonance (NMR) spectroscopy (1H,

13

C, 2D-COSY,

2D-HMQC, 2D-TOCSY, 2D-HSQC, and 2D-NOESY) [26], thin-layer chromatography (TLC) [42], ultra performance liquid chromatography (UPLC) [37], high performance size-exclusion chromatography (HPSEC) [45], high performance gel permeation chromatography (HPGPC) [16], hydrolysis, methylation analysis, periodate oxidation, and Smith degradation [37]. Since chemical structures are important factors in the biological activities, various AP with different primary chemical structures have been characterized. The origins, chemical structures, MW, 10

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biological

activities,

extraction

solvents,

and

monosaccharide

compositions are shown in Table 1. These AP from different species and regions showed significant difference in chemical structures, MW, monosaccharide compositions, and biological activities. Song et al. [37] found an acidic polysaccharide from A. polytricha (named AAFRC), which was homogenous with MW of about 1.20 × 103 13

of

kDa. The FTIR and NMR analysis (1H,

C, 2D-COSY, 2D-HMQC,

ro

2D-TOCSY, 2D-HSQC, and 2D-NOESY) showed that AAFRC was a

-p

glucan consisting 1, 3-β-glucan, 1, 4-α-glucan, and 1, 3-α-glucan

re

backbones with a single 1→)-α-D-glucopyranosyl side-branching unit on

lP

every 6 residues, on average, along the main chain. The structural

na

elucidation was helpful in determining the potential mechanisms underlying the biological effects of polysaccharides.

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Xu et al. [19] obtained a water-soluble neutral polysaccharide (named AF1) from A. auricula-judae. The MW of AF1 in both aqueous solution and DMSO were determined using laser light scattering (LLS) and size exclusion chromatography-LLS (SEC-LLS)，which were 2.1 × 103 and 2.2 × 103 kDa, respectively. AF1 was identified as a β-(1→3)-D-glucan with 2 β-(1→6)-D-glucosyl residues for every 3 main chain glucose residues using GC, GC-MS, and NMR (1H,

13

C, 2D-HMQC, and

2D-DQF), which had comb-branched structures. AF1 had high viscosity at low concentration (lower than 4.0 × 10-3 g/mL) at 25 ℃, and seemed to 11

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dissolve, which may make it to be applied in food, pharmaceutical, and cosmetic products [19]. A water-soluble β-D-glucan, named AAG, was separated from A. auricula-judae, GC, GC-MS, matrix-assisted laser desorption/ionization (MALDI)-time of flight (TOF) and NMR (1H, 13C, 2D-HSQC, and 2D-NOESY) analysis indicated that AAG was composed

of

of a main chain of (1→4)-D-glucopyranosyl with glucopyranosyl side groups at O-6 [22]. Two exopolysaccharides with different structural

ro

features, named CEPSN-1 and CEPSN-2, were obtained from submerged

-p

culture of A. auricula-judae, FTIR, HPLC, GC-MS, NMR and

chains

composed

of

lP

backbone

re

methylation analysis showed that both the 2 exopolysaccharides had (1→4)-α-D-glucose

residues

in

na

glucopyranose types and showed considerable antioxidant activities. These results indicated the AP with backbones of (1→4)-α-D-glucose

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may be potential immunomodulatory agents [25]. An A. polytricha polysaccharide (named AAP-2) was separated using HSCCC

with

an

aqueous

2-phase

system

of

PEG1000-K2HPO4-KH2PO4-H2O (0.50: 1.25: 1.25: 7.00, w/w). The results of partial hydrolysis, periodate oxidation, acetylation, methylation analysis, and NMR spectroscopy (1H,

13

C) showed that AAP-2 was a

polysaccharide with a backbone of (1→3)-linked-β-D-glucopyranosyl and (1→3, 6)-linked-β-D-glucopyranosyl residues in a 2: 1 ratio, and had 1 terminal (1→)-β-D-glucopyranosyl at the O-6 position of (1→3, 12

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6)-linked-β-D-glucopyranosyl of the main chain [8]. The chemical structures of these AP are similar to Letinous edodes polysaccharides and Ganoderma lucidum polysaccharides, which have been shown to have potential antitumor activities [46-47]. These results may provide some clues to the relationships between chemical structures and biological

of

activities of mushroom polysaccharides. Zeng et al. [1] separated a heteropolysaccharide form A. auricula (named

ro

AAP), which was characterized using FTIR, partial acid hydrolysis,

-p

periodic acid oxidant, Smith degradation, methylation analysis, and

re

atomic force microscopy (AFM). The results showed that AAP was

lP

composed of glucose, galactose, mannose, arabinose, and rhamnose at a

na

molar ratio of 37.5: 1.0: 4.3: 0.9: 0.9 with the MW of 27.7 kDa, which was observed as a spherical lump, and the backbone of AAP was mainly

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composed of glucose units with (1→3) links [1]. The AAP with low MW and high contents of glucose may be closely related to the heating mechanism of microwave-assisted extraction. These results may provide some new thoughts and methods for elaborating the relationships between chemical structures and biological activities of AP. In addition, 5 different water-soluble polysaccharides (named AAP1, AAP2, AAP3, AAP4, and AAP5) were separated from different varieties and different regions. GC analysis and antioxidant activity tests showed that these polysaccharides with highly different antioxidant activities consisted of various 13

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monosaccharides with different molar ratios. These results may show that the monosaccharide compositions are correlated to antioxidant activities of polysaccharides [20]. On the one hand MW and solution behavior of AP may be one of the key factors in the antioxidant activities, low MW and viscosity is favorable for the antioxidant activities, but on the other

of

hand, high content of neutral monosaccharide seems to have negative effect on them, while high acidic monosaccharide content promotes the

ro

antioxidant activities. Numerous AP have been isolated and characterized

-p

using various methods. These polysaccharides differ in rheological

re

properties, MW, monosaccharide compositions, chemical structures, and

lP

morphological characteristics, which is closely related to their biological

na

activities. The structure and bioactivities of AP have not been comprehensively studied, further studies are needed for elucidating the

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relationships between their chemical structures and biological activities. 4. Molecular modifications of AP and use as drug carriers To enhance or expand the potential biological activities and applications of AP, extensive modification methods and nanotechnologies have been used to change their structural and conformational properties, which are attributed to their abundant functional groups, good biodegradability, biocompatibility, good safety, and various biological activities. Research results have indicated that the bioactivities of polysaccharides are related to the types of glycosidic bonds, solubility, MW, and spatial 14

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configurations. Among them, the types of glycosidic bonds and monosaccharide compositions are important to determine whether the polysaccharides have bioactivities, while other factors can affect the level of bioactivities merely. Thus, molecular modifications can improve the bioactivities

of

by

changing

degradation

[29,

their

30],

chemical

sulfation

[12,

structures. 36,

41],

of

Physicochemical

AP

carboxymethylation [13, 48], hydrolysis [33], complexation [14, 16], and

ro

drug-loaded nanoparticles [49] of AP are the usual methods used. The

-p

results showed that they not only improved the biological properties of

re

AP, but also led to entirely new activities [50]. These physicochemical

lP

modifications of AP are listed in Table 2.

na

4.1 Physicochemical degradation

Previous studies have shown that degraded polysaccharides had better

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antitumor, antimicrobial, immunoregulatory, and antioxidant activities. Thus, the structure-activity relationships of AP need further study. Solution plasma processes (SPP) have advantages, including low energy consumption, moderate cost, and environmental friendliness [29]. A water-soluble polysaccharide was synergistically degraded using SPP in the presence of hydrogen peroxide. Particle size, Congo red, AFM, and scanning electron microscope (SEM) analysis showed that the degraded AP showed a rigid conformation and higher conformation flexibility. GPC analysis showed the MW distribution of degraded AP was narrower. 15

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Antioxidant activity tests indicated that the degraded AP showed a better metal

chelating

activity,

reducing

(2,2'-Azino-di-[3-ethylbenzthiazoline 2-diphenyl-1-picrylhydrazyl

power,

sulfonate

(DPPH),

and

and

radical

(ABTS),

superoxide

2,

radicals)

scavenging activities. FTIR and NMR analysis showed that no differences were observed in chemical structures between degraded and

of

natural AP [29-30]. The FTIR peaks of 1064 and 3430 cm–1 became

ro

stronger, but 2930 cm–1 became weaker, which results indicated that the

-p

hydrogen bonds and backbone lengths of AP had been broken during the

re

degradation, more hydrogen and alkyl bonding groups were exposed. The

lP

better antioxidant activities of degraded AP are directly related to the

na

monosaccharide components [51]. More methods are needed to obtain lower MW AP with better bioactivity, including ultrasonic technology,

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microwave exposure, high pressure homogenization, steam explosion, enzymatic hydrolysis, bio-fermentation, chemical method. 4.2 Sulfated modification

Recently, sulfated polysaccharides have been one of the hotspots in the field of natural polysaccharide research for their outstanding bioactivities, especially immunological

activities.

In

addition,

many sulfated

modification methods have been employed for improving anticoagulant, antioxidative, antitumor, and antivirus activities of AP, including chlorosulfonic acid-pyridine, concentrated sulfuric acid, and sulfur 16

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trioxidepyridine

methods

[52].

Sulfated

modification

promoting

bioactivities of polysaccharides were mainly attributed to their effects on structure

characteristics,

including

degree of substitution

(DS),

monosaccharide compositions, and substituted positions of sulfated groups. As the most commonly used methods, chlorosulfonic acid

of

(CSA)-pyprine, aminosulfonic acid (ASA)-pyridine and sulfur trioxide (ST)-pyridine methods have been widely used for the sulfated

ro

modifications of AP. However, the disadvantages of CSA-pyprine method

-p

are of concern, such as strong oxidizing and stimulating effects of CSA,

re

damaging the structures of polysaccharides, and complex operation. The

lP

ASA-pyridine method may be a better method because of its milder

na

reaction and better yield. Three AP were modified using the chlorosulfonic acid-pyridine method to obtain sulfated AP. The DS of 3

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sulfated AP were shown to be 0.22, 1.19, and 1.46, respectively. Antiviral assays showed that the sulfated AP showed better antiviral activities than the natural ones [12]. The immuno-enhancing activities in vitro and in vivo of natural AP were promoted using sulfation [41]. Two AP (named AAAP and NAAP) were sulfated into SAAAP and SNAAP using the sulfur trioxide-pyridine method [36]. The DS were 0.90 and 0.78, respectively, both of which showed stronger antioxidant activities than the natural ones in superoxide radical scavenging activity assays in vitro. FTIR analysis showed that sulfated AP had 2 characteristic absorption 17

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bands: One at 1235 or 1258 cm-1 representing an asymmetrical stretching vibration related to S=O groups, and the other at 810 or 819 cm-1 representing a symmetrical C-O-S vibration associated with C-O-SO3 groups [48]. The sulfation in the AP molecules may activate the hydrogen atoms of the anomeric carbons or provide hydrogens for binding with

of

hydroxyl radicals and form stable radicals, leading to an enhancement in antioxidant activities. Sulfated AP with higher DS showed better

by

structures,

monosaccharide

-p

influenced

ro

scavenging activities. The structural differences of sulfated AP can be compositions

of

re

polysaccharides, and acidic condition during sulfation, which determines

na

4.3 Carboxymethylation

lP

their distinct biological activities.

Both the water solubility and bioactivities of polysaccharides can be

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effectively improved using carboxymethylation [13]. Various natural polysaccharides have been modified using carboxymethylation, including chitosan [53], cellulose [54], guar gum [55], and chitin [56]. Two carboxymethylated AP (named CMAAP and CMAAP22) were obtained using the chloroacetic acid-NaOH method with solubility of 0.6 mg/mL and DS of 0.86, respectively [13]. Both showed better scavenging of hydroxyl, DPPH, and ABTS radicals than the natural ones. FTIR analysis indicated that carboxymethylated AP had moderate-intensity peaks mainly in the ~1640 - 1600 and ~1430 - 1400 cm-1 [48]. These strong 18

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absorption bands of the carboxymethylated derivatives were considered as the results of the asymmetrical and symmetrical COO- stretching vibrations. NMR analysis showed that the carboxymethyl substitution occurred at the C-2, C-4, and C-6 positions. Carboxymethylated AP showed better radioprotective activities at the dose range of ~200 - 500

of

μg/mL than the natural ones [48]. 4.4 Hydrolysis

ro

Two hydrolysates of AP were obtained using a sulfuric acid/hydrochloric

-p

acid-hydrolysis methods, named AAP-F and APHs. GC-MS and HPLC

re

analysis indicated that AAP-F was a heteropolysaccharides with MW of

lP

143 kDa, and comprised of glucose, galactose, and fucose with the molar

na

ratio of 50.0: 1.0: 2.0. The latter also was a heteropolysaccharides and composed of arabinose, xylose, mannose, glucose, galactose, and

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glucosamine with the molar ratio of 1.9: 0.5: 2.9: 1.0: 0.7: 0.2. A Box-Behnken design (BBD) was performed for the optimization of acid-hydrolysis conditions to obtain optimal condition of AAP-F: hydrolyzing time, 2.8 h; hydrolyzing temperature, 95.0 ℃; the acid concentration, 14.0 M. The AAP-F showed significant protective effects to the injury induced by hydrogen peroxide or paraquat [33]. APHs could increase the levels of hepatic glycogen and pancreatic insulin, decreased the serum TG and LDL-C levels, and had no significant effects on the levels of total cholesterol and HDL-C [50]. 19

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4.5 Complexes The “one pot” method has been known as an efficient strategy for improving the efficiency of chemical reactions [14]. Qiu et al. [14] successfully synthesized AP-CDDP complexes (named AAP-CDDP) and obtained the optimal preparation conditions using RSM: pH, 7.7; reaction

of

time, 1.8 h; reaction temperature, 56.9 ℃; and amount of CDDP, 6.0 mg. FTIR and NMR analysis showed that the AP combined with CDDP at the

ro

hydroxyl groups of the polysaccharide’s chains [14]. The antitumor

-p

assays both in vitro and in vivo indicated that AAP-CDDP complexes

re

showed significant antitumor activities against HeLa cells [15]. A

lP

polyelectrolyte complex nanoparticle (named AAP/LCS NP) was

na

prepared by mixing negatively charged AP with positively charged low MW chitosan using a coacervation method. Particle size and morphology

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analysis showed the AAP/LCS NP had a spherical shape with a diameter of 223 nm and a smooth surface. FTIR analysis showed that the carboxylic groups of AP reacted with the protonated amino groups of chitosan through electrostatic interactions to form polyelectrolyte complexes [16]. A pH-sensitive AP hydrogel (named AAP) was appropriately cross-linked with 1 mL AAP (50 mg/mL) and 0.25 mL epichlorohydrin. SEM and FTIR analysis confirmed that the AP hydrogel had stronger water uptake capacity, and several stronger peaks at ~1000 1200 and 2926 cm-1 [57]. 20

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4.6 Drug-loaded nanoparticles Polysaccharides have been extensively studied as drug carriers because of their biocompatibility, biodegradability, good safety profile, and low-cost availability. Furthermore, various functional groups, including hydroxyl, amino, carboxylate, sulfate, and ester groups can be used to prepare

of

polysaccharide nanoparticles for biomedical applications [58]. To enhance the loading of doxorubicin hydrochloride (Dox·HCl) in

ro

nanodrug delivery systems, a Dox-loaded AP-chitosan nanoparticle

-p

(named Dox AAP-CS NP) was successfully prepared using a

re

polyelectrolyte coacervation method. FTIR and TEM analysis suggested

lP

that the Dox AAP-CS NP had spherical morphologies with average

na

diameter of 238 nm and 74.1% Dox·HCl encapsulation efficiency [49]. In vitro cytotoxicity studies showed that Dox AAP-CS NP can significantly

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improve the cytotoxicity of Dox·HCl against MCF-7 cells by increasing celluar uptake, compared to free Dox·HCl. A histidine modified AP paclitaxel micelle (named His-AAP-PTX) was prepared using a self-assembled organic solvent evaporation method. Dynamic light scattering

(DLS)

and

morphology

analysis

showed

that

the

His-AAP-PTX micelles had spherical morphologies with a diameter of 157 nm and an 80.3% PTX encapsulating efficiency. Compared with Taxol, His-AAP-PTX micelles had better antitumor activities both in vitro and in vivo [17]. 21

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To better understand the effect of AP’s dimensional structures, MW, solubility, intrinsic viscosity, and the substituent groups’ types, numbers, and positions on their bioactivities, more molecular modification methods should be applied, including phosphorylation, selenization, acetylation, alkylation, acid/alkali degradation, microwave exposure, radiation-induce

of

treatments, bio-fermentation, and enzyme modifications. 5. Biological activities of AP and their derivatives

ro

As one of the traditional Chinese edible and medicinal mushrooms, the

-p

Auricularia mushrooms have also been widely used as health foods and

re

food supplements. It has been confirmed that they have various biological

lP

activities, including antioxidant, hepatoprotective, antitumor, and

na

immunomodulatory activities [59]. 5.1 Antioxidant activity

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Free radicals have been known to be harmful to living organisms and have an important role in many lifestyle-related diseases, including aging, cancer,

atherosclerosis,

and

diabetes

[60].

Polysaccharides

or

polysaccharide-protein complexes have been thought as the main antioxidants of mushrooms. Using both in vitro and in vivo assays, the antioxidant activities of AP have been widely confirmed to be mediated by free radical scavenging, lipid peroxidation inhibition, and enhancing superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities. A series of in vitro tests have been used to measure 22

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the abilities of AP to scavenge DPPH, hydroxyl, and superoxide radicals, reducing power and the ability to chelate ferrous ions [61]. There was an AP extracted from A. auricula harvested in Sichuan province that dose-dependently scavenged ABTS (EC50= 1.2 mg/mL), DPPH (EC50= 3.3 mg/mL), superoxide (EC50= 0.7 mg/mL), and hydroxyl radicals (EC50

of

= 9.0 mg/mL), and inhibited peroxidation of egg yolk homogenate (EC50= 0.1 mg/mL) [1]. Five different water-soluble polysaccharides (named

ro

AAP1, AAP2, AAP3, AAP4, and AAP5) with different molar ratio of

-p

monosaccharide compositions were obtained from different varieties of A.

re

auricula. These polysaccharides were observed to have different

lP

scavenging activities against DPPH, superoxide, and hydroxyl radicals, as

na

well as chelating abilities and reducing power (AP from Northeast China had the best antioxidant activities), which showed that the antioxidant

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activities of AP may be closely related to the varieties, regions, and molar ratio of monosaccharides [20]. Ma et al. [29] found that, compared to natural AP, degraded AP using SPP with H2O2 had lower intrinsic viscosity and MW, but showed stronger abilities to scavenge ABTS, DPPH, and superoxide radicals. These results indicated that the antioxidant activities of AP may also be correlated with intrinsic viscosities and MW [29-30], as well as monosaccharide compositions, chemical structures, contents of uronic acids, and chain conformations [45]. Both the water-soluble polysaccharide (named AAP I-a) and crude 23

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AP had been observed to significantly down-regulate the levels of malondialdehyde (MDA) and increased SOD and GSH activities in aging mice that induced by D-galactose [35, 43]. Both low MW and high acidic monosaccharide contents are favorable for the antioxidant activities of AP, but high contents of neutral monosaccharides seem to have negative

of

effects on the activities. Many AP derivatives have been prepared and show better antioxidant activities than natural ones, including

ro

carboxymethylated [13], sulfated [36], and hydrolyzed AP [33], which are

-p

helpful for understanding the relationships between structures and

re

antioxidant activities of AP, but also greatly expanded the applications.

lP

The underlying mechanisms of antioxidant activities of AP remain

na

unclear. One of the mechanisms may be attributed to the hydrogen atom-donating ability of a molecule to a radical, which induces

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termination of radical chain reactions and converts free radicals to non-harmful products. AP with structures containing 2 or more of the following functional groups: -OH, -SH, -COOH, -PO3H2, C=O, -NR2, -S-, and -O- also showed better metal chelating activities. To explore high potential antioxidant agents, further studies are needed to elucidate the structure-function relationships of AP. 5.2 Antitumor activity Ever since the antitumor activity of a water-soluble AP with a branched β-(1→3)-D-glucan (named glucan I), which was first reported by Misaki 24

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et al. in the 1980s, showed potent inhibitory activity against implanted S180 solid tumor in mice, the antitumor activity has been studied [6]. A β-configuration polysaccharide (named APPIIA) with a MW of 110 kDa, composed of mannose and xylose, was observed to inhibit the tumor proliferation of S180 tumor-bearing mice, and improve their quality of life

of

[42]. The antitumor activities may be related to the sulfate groups, which were naturally presented in the polysaccharides. A water soluble

ro

β-D-glucan (named AAG) showed inhibition ratios of 23.5 and 34.1%

-p

against Acinar cell carcinoma cells in vitro at 0.005 and 0.050 mg/L,

re

respectively, and induced S180 tumor cells apoptosis by up-regulating the

lP

levels of Bax and down-regulating the levels of Bcl-2. The inhibition

na

ratio of AAG (injected intraperitoneally at 20 mg/kg), AAP-2 (injected intraperitoneally at 12 mg/kg), and AAFRC (injected intraperitoneally at

Jo ur

24 mg/kg) against S180 tumor cells was 39.1 [62], 40.4, and 43.6%, respectively [8, 37]. AP was confirmed to inhibit the proliferation and DNA syntheses of A549 cells in a dose-dependent manner. The AP induced cell apoptosis by arresting the cell cycle at G0/G1, which was mediated by decreasing expressions of cyclin A, cyclin D, and CDK2, as well as increasing expressions of p21 and p53 [63]. AP was observed to inhibit the proliferation of HeLa cells both in vitro and in vivo [15, 59]. Similar to other mushroom polysaccharides, AP with β-(1→3)-D-glucan in their main chains usually showed good antitumor activities. A 25

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β-glucans containing mainly 1→6 linkages showed weaker activities, which was thought to be attributed to their inherent flexibility, i.e., of having too many possible conformations. Various types of AP-based drug loading system nanoparticles have been developed and used for antitumor drugs,

including

Dox

AAP-chitosan

nanoparticles

[49],

of

histidine-modified AAP PTX micelles [17], and FA-AAP-CDDP complexes [59]. These results confirmed that AP might not only be a

ro

potential antitumor agent, but also a class of ideal natural antitumor drug

-p

delivery carriers. It is noteworthy that it may require several grams of AP

re

for direct tumor cell killing by intravenous injection, which could

reasonable

for

AP

killing

tumor

cells

through

their

na

more

lP

significantly increase adverse effects and risk. In comparison, it may be

immunomodulatory effects.

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5.3 Immunomodulatory activity

Yu et al. [42] reported that a polysaccharide (named APPIIB) with a MW of less than 110 kDa could stimulate macrophage to transcribe and secrete another 2 cytokines, IL-1β, and IL-6. The phagocytosis of macrophage RAW 264.7 cells was increased by increasing the solubility and particulate antigens uptake capacities [42]. Triple helical conformations of (1→3)-β-glucan in mushroom polysaccharides have been generally believed to be closely related to their immuno-stimulating activities. However, 2 exopolysaccharides, named CEPSN-1 and CEPSN-2, both 26

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had backbone chains composed of (1→ 4)-α-D-glucose residues could promote the release of NO and cytokines (IL-6, IL-10, and TNF-α) in RAW 264.7 cells [25]. Wu et al. [43] found that AP isolated from A. auricula could increase the weights of the spleen and thymus in aged mice after oral administration, which suggested that AP may modulate the

of

immune functions of aged mice [43]. A sulfated AP (named sAAPt) was shown to promote the proliferation of chicken peripheral lymphocytes in

ro

vitro and in vivo, which suggested that sAAPt might be a different type of

-p

immunopotentiator [41]. The sulfated polysaccharides have attracted

re

widespread attention for their immunomodulatory activities in past 5

lP

years, which improve the immune system by regulating macrophages,

na

T/B lymphocytes, natural killer cells (NK cells), and complement systems. Natural AP can activate the innate immune system and effector cells,

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including macrophages, T-lymphocytes, B-lymphocytes, and NK cells to express cytokines, including TNF-α, IL-6, IL-10, and IL-1β. 5.4 Hypolipidemic activity

Hypercholesterolemia has been identified as a major risk factor for cardiac illness and death, including atherosclerosis, hypertension, and other cardiovascular diseases. The mushroom polysaccharides with hypolipidemic activities is considered to contain β-(1→3)-glucans in their main chains, and β-(1→6)-glucans in their side chains. A glycoprotein with a MW of 32 kDa was obtained from A. polytricha, which could 27

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significantly decrease the concentrations of the plasma triacylglycerols, total cholesterol and low-density lipoprotein (LDL) cholesterol in the dietary-induced hyperlipidemic rats [44]. Zeng et al. [26] purified an α-glycosidically linked AP (named AAP-I), after 14 and 28 days of AAP-I orally administered, the AAP-I significantly decreased the levels of total

of

cholesterol, triglyceride, and LDL in mice with hyperlipidemia induced by high fat diets [26]. A soluble polysaccharide (SPAP) was observed to

ro

decrease the serum concentrations of blood lipids in diet-induced

-p

hypercholesterolemic rats to normal levels [27]. AP can inhibit the

re

absorption of exogenous lipids by binding with lipid molecules or cholate

lP

in the gastrointestinal tracts and promoted total cholesterol metabolism.

na

MW, monosaccharide compositions, uronic acid contents and chain conformations of AP may have important roles in the hypolipidemic

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activities, such as polysaccharides with larger MW (larger intrinsic viscosity and stronger hydrophobicity) have stronger ability to bind with lipid molecules or cholate. 5.5 Antidiabetic activity Non-insulin-dependent diabetes (NIDD, type II) has been widely considered to be induced by both genetic and environmental factors, especially diets and physical activities. For example, high-fat diets used to be the major cause of obesity-associated insulin resistance. Takeuchi et al. [64] found that when genetically diabetic (type II) KK-Ay mice were 28

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given diets containing 20% fats with 5% hot-water extracts from A. auricula-judae Quel. for 3 wk, no significant changes in body weight and plasma glucose concentrations were observed compared to the positive control group, which was given the same diet [64]. Diet streptozotocin (STZ)-induced diabetic Sprague-Dawley rats were orally administered

of

with AP (100 and 400 mg/kg bw) for 4 wk. AP strongly reduced blood glucose levels by promoting glucose metabolism, and effectively

ro

prevented diabetic nephropathy by regulating the levels of blood urea

-p

nitrogen, creatinine, uric protein, and inflammatory-related factors [65].

re

More and more studies have shown that the mechanism of

lP

polysaccharides alleviating type II diabetes may be associated with lipid

na

metabolism and gut microbiota changes, thus the mechanism of AP in treatment of type II diabetes may be elaborated by their effects on gut

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microbiota and their metabolites [66]. 5.6 Anticoagulant activity

Both blood coagulation and platelet aggregation have important roles in the pathogenesis of ischemic diseases. The coagulation process leads to the formation of thrombin, and platelets are activated and aggregate in response to various endogenous substances. Then the activated platelets participate in the propagation of thromboembolism causing ischemic diseases. Yoon et al. [21] found the anticoagulant activity of the acid AP was closely related to catalysis of thrombin inhibition by antithrombin but 29

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not by heparin cofactor II. Three extraction techniques, namely, high intensity pulsed electric fields (HIPEF), microwave-assisted extraction method (MAEM), and ultrasonic-assisted extraction method (UAEM), were used to optimize the extraction conditions of AP from 3 stains of Jew’s ear from Jilin province (named 988, DY 18, and FS 02). The

of

anticoagulant activities of these polysaccharides were measured using activated partial thromboplastin (APTT) and prothrombin (PT) clotting

ro

time assays. The results suggested that all the polysaccharides could

-p

prolong blood clotting times with the polysaccharides extracted using

re

HIPEF showing the best anticoagulant activities. This suggested that

lP

HIPEF may be an effective method for the extractions of bioactive

na

natural polysaccharides [9].

5.7 Hepatoprotective activities

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Hepatoprotective effects of A. cornea var. Li. polysaccharides (named AP) and enzymatic-extractable AP (EAP) on the acute alcohol-induced alcoholic liver diseases (ALD) were measured. Both AP and EAP showed potential hepatoprotective effects with ALD through improving the alcohol metabolism, preventing the alcohol-induced histopathological alterations, inhibiting the expression levels of inflammatory mediators, increasing the antioxidant activities, and reducing the lipid peroxidation. Abundant xylose and glucose contents may be closely related to these biological activities [67]. 30

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5.8 Other biological activities Generally, the natural polysaccharides have no or little antiviral activities, sulfated modification has been commonly used to obtain or improve these activities [3]. Sulfated AP (named sAAP) significantly inhibit the celluar infectivity of Newcastle disease virus in vitro, which shows better activity than the natural one [12]. The antiviral mechanism was thought to involve

of

SO42- polyanions of sAAP combining with virus or cells, thus inhibiting

ro

virus adsorption or suppressing virus replication after entering the cell.

-p

Comparing the antibacterial activities of commercial chitosan and

re

chitosan isolated from A. sp., Chang et al. [68] concluded that the latter

lP

one had better antibacterial activities against both Gram-positive and

na

Gram-negative bacteria than the commercial ones. The potential mechanisms may be closely related to the degree of deacetylation of the

Jo ur

chitosan. Therefore, the degree of deacetylation of AP may be an important factor in improving its bioactivities. 6. Conclusions and future perspectives Auricularia mushrooms have been widely consumed as an edible and medicinal mushroom in various parts of the world for thousands of years. The polysaccharides from Auricularia have been considered as a major bioactive component, which suggests that further development might be beneficial. Growing evidence has identified many important biological activities and functions of AP with MW ranging from ~4.6 - 3400 kDa. 31

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Previous studies have been focused on the extraction, purification, structures, modifications, and bioactivities of AP, especially the modification methods: sulfation, carboxymethylation, hydrolysis, solution plasma processes, coordination processes, and nanocrystallization, which can

significantly

improve

structural

characteristics,

strengthen

antitumor,

of

bioactivities, and even lead to new bioactivities, including antioxidant, immunoregulatory,

antiviral,

radioprotective,

and

ro

hypoglycaemic activities. Although many chemical structures and

-p

biological activities of AP and its derivatives have been elucidated, the

re

complicated structures and unclear mechanisms of actions still need to be

lP

further explored. Since the biological activities of polysaccharides are

na

closely related to their rheological properties, MW, chemical structures, monosaccharide components, and substituent groups, further in-depth

Jo ur

structural analysis of AP needs to be systematically carried out and the exact chemical structures of AP established. In addition, the relationships between the biological activities of AP and their effects on gut microbiota also need to be elaborated. More modification methods may be used for further elucidating the relationships between structures, substituent groups, and bioactivities of AP, including physical (ultrasonic disruption, radiation treatment, microwave exposure, high pressure homogenization, steam explosion), chemical (alkylation, phosphorylation, selenization, and acetylation), and biological modifications (enzymatic degradation) 32

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[69-71]. The identification and characterization of bioactive polysaccharides from Auricularia might provide opportunities to expand the use of Auricularia. This review also provides better understanding of the polysaccharides from Auricularia and new insights for the further research and

na

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Conflicts of interest

lP

re

-p

ro

of

development of these polysaccharides.

The authors of the paper have no financial or personal relationships with other people or organizations that would create a conflict of interest.

Acknowledgments This work was supported by the National Science Foundation of China (31401483), the National Science Foundation of Heilongjiang Province, China (C2018034), and the Post-Doctoral Fund of Heilongjiang Province (LBH-Z14098).

33

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References [1] W.C. Zeng, Z. Zhang, H. Gao, L.R. Jia, W.Y. Chen, Characterization antioxidant

polysaccharides

from Auricularia

auricular using

of

of

microwave-assisted extraction, Carbohyd. Polym. 89 (2012) 694-700.

ro

[2] F. Wu, Y. Yuan, V. Malysheva, P. Du, Species clarification of the most

-p

important and cultivated Auricularia mushroom “Heimuer”: Evidence

re

from morphological and molecular data, Phytotaxa 186 (2014) 241-253.

lP

[3] A.R. Bandara, S.C. Karunarathna, J. Chen, K.D. Hyde, Auricularia

na

thailandica sp. nov. (Auriculariaceae, auriculariales) a widely distributed species from southeastern Asia, Phytotaxa 208 (2015) 147-156.

Jo ur

[4] M. Zhang, S.W. Cui, P.C.K. Cheung, Q. Wang, Antitumor polysaccharides from mushrooms: A review on their isolation process, structural characteristics and antitumor activity, Trends Food Sci. Tech. 18 (2007) 4-19. [5] Y. Sone, M. Kakuta, A. Misaki, Isolation and characterization of polysaccharides of "Kikurage", fruit body of Auricularia auricula-judae, Agr. Biol. Chem. 42 (1978) 417-425. [6] A. Misaki, M. Kakuta, T. Sasaki, M. Tanaka, H. Miyaji, Studies on interrelation of structure and antitumor effects of polysaccharides: 34

Journal Pre-proof

Antitumor action of periodate-modified, branched (1→3)-β-D-glucan of Auricularia auricula-judae, and other polysaccharides containing (1→3)-glycosidic linkages, Carbohyd. Res. 92 (1981) 115-129. [7] L.S. Fan, S.H. Zhang, L. Yu, L. Ma, Evaluation of antioxidant property and quality of breads containing Auricularia auricula

of

polysaccharide flour, Food Chem. 101 (2006) 1158-1163. [8] G.L. Song, Q.Z. Du, Isolation of a polysaccharide with anticancer

ro

activity from Auricularia polytricha using high-speed countercurrent

-p

chromatography with an aqueous two-phase system, J. Chromatogr. A

re

1217 (2010) 5930-5934.

lP

[9] C.T. Li, X.X. Mao, B.J. Xu, Pulsed electric field extraction enhanced

na

anti-coagulant effect of fungal polysaccharide from Jew’s ear (Auricularia auricula), Phytochem. Analysis 24 (2012) 36-40.

Jo ur

[10] L. Loukotová, R. Konefał, K. Venclíková, D. Machová, O. Janoušková, M. Rabyk, et al., Hybrid thermoresponsive graft constructs of

fungal

polysaccharide

β-glucan:

physico-chemical

and

immunomodulatory properties, Eur. Polym. J. 106 (2018) 118-127. [11] C.Q. Tong, Y.X. Zheng, G.L. Guo, W. Li, Hepatoprotective effect of a polysaccharide from Auricularia auricula root on acute model of liver injury, Glycobiology 25 (2015) 1287. [12] T.L. Nguyen, J. Chen, Y.L. Hu, D.Y. Wang, Y.P. Fan, J.M. Wang, et al., In vitro antiviral activity of sulfated Auricularia auricula 35

Journal Pre-proof

polysaccharides, Carbohyd. Polym. 90 (2012) 1254-1258. [13] L.Q. Yang, T. Zhao, H. Wei, M. Zhang, Y. Zou, G.H. Mao, et al., Carboxymethylation of polysaccharides from Auricularia auricula and their antioxidant activities in vitro, Int. J. Biol. Macromol. 49 (2011) 1124-1130.

of

[14] J.Q. Qiu, H. Zhang, Z.Y. Wang, S.M. Liu, J.M. Regenstein, Response surface methodology for the synthesis of an Auricularia

93 (2016) 333-343. J.Q.

Qiu,

H.

Zhang,

re

[15]

-p

ro

auricula-judae polysaccharides-CDDP complex, Int. J. Biol. Macromol.

Z.Y.

Wang,

Auricularia

lP

auricula-judae polysaccharide-cisplatin complexes conjugated with folic

966-974.

na

acid as new tumor targeting agents, Int. J. Biol. Macromol. 120 (2018)

Jo ur

[16] W. Xiong, Q.T. Zhang, F. Yin, S.H. Yu, T.T. Ye, W.S. Pan, et al., Auricularia auricular polysaccharide-low Mw chitosan polyelectrolyte complex nanoparticles: Preparation and characterization, Asian J. Pharm. Sci. 11 (2016) 439-448. [17] Y.Y. Wang, P.F. Li, F. Chen, L.Q. Jia, Q.H. Xu, X.M. Gai, et al., A novel pH-sensitive carrier for the delivery of antitumor drugs: Histidine-modified Auricularia auricular polysaccharide nanomicelles, Sci. Rep. 7 (2017) 4751. [18] R. Zhou, H.H. Bao, Y.H. Kang, Synergistic rheological behavior and 36

Journal Pre-proof

morphology

of

yam

starch

and

Auricularia

auricula-judae

polysaccharide-composite gels under processing conditions, Food Sci Biotechnol. 26 (2017) 883-891. [19] S.Q. Xu, X.J. Xu, L.N. Zhang, Branching structure and chain conformation of water-soluble glucan extracted from Auricularia

of

auricula-judae, J. Agr. Food Chem. 60 (2012) 3498-3506. [20] S. Xu, Y. Zhang, K. Jiang, Antioxidant activity in vitro and in vivo of

ro

the polysaccharides from different varieties of Auricularia auricula, Food

-p

Funct. 7 (2016) 3868-3879.

The

nontoxic

mushroom

Auricularia

lP

al.,

re

[21] S.J. Yoon, Y. Ma, Y.R. Pyun, J.K. Hwang, D.C. Chu, L.R. Juneja, et auricula

contains

a

na

polysaccharide with anticoagulant activity mediated by autithrombin, Thromb. Res. 112 (2003) 151-158.

Jo ur

[22] Z.C. Ma, J.G. Wang, L.N. Zhang, Structure and chain conformation of β-glucan isolated from Auricularia auricula-judae, Biopolymers 89 (2008) 614-622.

[23] L.J. Zhang, M.S. Wang, PEG-based ultrosound-assisted extraction of polysaccharides from superfine ground Auricularia auricular, J. Food Process. Pres. 42 (2017) e13445. [24] L.N. Zhang, L.Q.Yang, Q. Ding, X.F. Chen, Studies on molecular weights of polysaccharides of Auricularia auricula-judae, Carbohyd. Res. 270 (1995) 1-10. 37

Journal Pre-proof

[25] Y. Zhang, Y. Zeng, Y. Men, J.G. Zhang, H.M. Liu, Y.X. Sun, Structural

characterization

exopolysaccharides

from

and

immunomodulatory

submerged

culture

of

activity

of

Auricularia

auricula-judae, Int. J. Biol. Macromol. 115 (2018) 18978-18984. [26] F. Zeng, C. Zhao, J. Pang, Z.X. Lin, Y.F. Huang, B. Liu, Chemical

of

properties of a polysaccharide purified from solid-state fermentation of Auricularia auricular and its biological activity as a hypolipidemic agent,

ro

J. Food Sci. 78 (2013) H1470-1475.

-p

[27] S. Zhao, C.B. Rong, Y. Liu, F. Xu, S.X. Wang, C.L. Duan, et al.,

re

Extraction of a soluble polysaccharide from Auricularia polytricha and

na

Polym. 122 (2015) 39-45.

lP

evaluation of its anti-hypercholesterolemic effect in rats, Carbohyd.

[28] Y. Zou, A.L. Jiang, M.X. Tian, Extraction optimization of antioxidant

Jo ur

polysaccharides from Auricularia auricula fruiting bodies, Food Sci. Technol. 35 (2015) 428-433. [29] F.M. Ma, J.W. Wu, P. Li, D.B. Tao, H.T. Zhao, B.Q. Zhang, et al., Effect of solution plasma process with hydrogen peroxide on the degradation of water-soluble polysaccharide from Auricularia auricula. II: Solution conformation and antioxidant activities in vitro, Carbohyd. Polym. 198 (2018) 575-580. [30] J.W. Wu, P. Li, D.B. Tao, H.T. Zhao, R.Y. Sun, F.M. Ma, et al., Effect of solution plasma process with hydrogen peroxide on the 38

Journal Pre-proof

degradation and antioxidant activity of polysaccharide from Auricularia auricula, Int. J. Biol. Macromol. 117 (2018) 1299-1304. [31] H.H. Bao, S.G. You, L.K. Cao, R. Zhou, Q. Wang, S.W. Cui, et al., Chemical and rheological properties of polysaccharides from fruit body of Auricularia auricular-judae, Food Hydrocolloid. 57 (2016) 30-37.

of

[32] S.G. Khaskheli, W. Zheng, S.A. Sheikh, A.A. Khaskheli, Y. Liu, A.H. Soomro, et al., Characterization of Auricularia auricula polysaccharides

-p

Macromol. 81 (2015) 387-395.

ro

and its antioxidant properties in fresh and pickled product, Int. J. Biol.

re

[33] Y.Y. Xu, M. Shen, Y.D. Chen, Y.Q. Lou, R.C. Luo, J.J. Chen, et al.,

lP

Optimization of the polysaccharide hydrolysate from Auricularia

na

auricula with antioxidant activity by response surface methodology, Int. J. Biol. Macromol. 113 (2018) 543-549.

Jo ur

[34] L.Q. Yang, L.M. Zhang, Chemical structural and chain conformational characterization of some bioactive polysaccharides isolated from natural sources, Carbohyd. Polym. 76 (2009) 349-361. [35] H. Zhang, Z.Y. Wang, Z. Zhang, X. Wang, Purified Auricularia auricular-judae polysaccharide (AAP I-a) prevents oxidative stress in an aging mouse model, Carbohyd. Polym. 84 (2011) 638-648. [36] H. Zhang, Z.Y. Wang, L. Yang, et al., In vitro antioxidant activities of sulfated derivatives of polysaccharides extracted from Auricularia auricular, Int. J. Mol. Sci. 12 (2011) 3288-3302. 39

Journal Pre-proof

[37] G.L. Song, Q.Z. Du, Structure characterization and antitumor activity of an α β-glucan polysaccharide from Auricularia polytricha, Food Res. Int. 45 (2012) 381-387. [38] H.N. Bai, Z.Y. Wang, J. Cui, K.L. Yun, H. Zhang, R.H. Liu, et al., Synergistic

radiation

protective

effect

of

purified

Auricularia

of

auricular-judae polysaccharide (AAP IV) with grape seed procyanidins, Molecules 19 (2014) 20675-20694.

ro

[39] K.L. Cheong, D.T. Wu, Y. Deng, F. Leong, J. Zhao, W.J. Zhang, et al,

-p

Qualitation and quantification of specific polysaccharides from Panax

re

species using GC–MS, saccharide mapping and HPSEC-RID-MALLS,

lP

Carbohyd. Polym. 153 (2016) 47-54.

na

[40] Y.Y. Chen, Y.T. Xue, Purification, chemical characterization and antioxidant activities of a novel polysaccharide from Auricularia

Jo ur

polytricha, Int. J. Biol. Macromol. 120 (2018) 1087-1092. [41] T.L. Nguyen, D. Wang, Y.L. Hu, Y.P. Fan, J.M. Wang, S. Abula, et al., Immuno-enhancing

activity

of

sulfated

Auricularia

auricula

polysaccharides, Carbohyd. Polym. 89 (2012) 1117-1122. [42] M.Y. Yu, X.Y. Xu, Y.A. Qing, X. Luo, Z.R. Yang, L.Y. Zheng, Isolation

of

an

anti-tumor

polysaccharide

from Auricularia

polytricha (Jew’s ear) and its effects on macrophage activation, Eur. Food Res. Technol. 228 (2009) 477-485. [43] Q. Wu, Z.P. Tan, H.D. Liu, L. Gao, S.J. Wu, J.W. Luo, et al., 40

Journal Pre-proof

Chemical characterization of Auricularia auricula polysaccharides and its pharmacological effect on heart antioxidant enzyme activities and left ventricular function in aged mice, Int. J. Biol. Macromol. 46 (2010) 284-288. [44] B.K. Yang, J.Y. Ha, S.C. Jeong, Y.J. Jeon, K.S. Ra, S. Das, et al.,

of

Hypolipidemic effect of an exo-biopolymer produced from submerged mycelial culture of Auricularia polytricha in rats, Biotechnol. Lett. 24

ro

(2002) 1319-1325.

-p

[45] Y.X. Sun, J.C. Liu, J.F. Kennedy, Purification, composition analysis

re

and antioxidant activity of different polysaccharide conjugates (APPs)

na

(2010) 299-304.

lP

from the fruiting bodies of Auricularia polytricha, Carbohyd. Polym. 82

[46] Y.T. Tian, Y.T. Zhao, H.L. Zeng, Y.L. Zhang, B.D. Zheng, Structural

Jo ur

characterization of a novel neutral polysaccharide from Lentinus giganteus and its antitumor activity through inducing apoptosis, Carbohyd. Polym. 154 (2016) 234-240. [47] Y.L. Fu, L. Shi, K. Ding, Structure elucidation and anti-tumor activity in vivo of a polysaccharide from spores of Ganoderma lucidum (Fr.) Karst, Int. J. Biol. Macromol. 141 (2019) 693-699. [48] H. Zhang, Z.Y. Wang, Z.L. Fan, X. Yang, X. Wang, N. Zhang, Radiation protection of carboxymethylation of an acid polysaccharide extracted from Auricularia auricula against UVb in vitro, Adv. Mater. 41

Journal Pre-proof

365 (2012) 199-204. [49] W. Xiong, L. Li, Y.Y. Wang, Y.B. Yu, S.X. Wang, Y.Y. Gao, et al., Design and evaluation of a novel potential carrier for a hydrophilic antitumor

drug:

Auricularia

auricular

polysaccharide-chitosan

nanoparticles as a delivery system for doxorubicin hydrochloride, Int. J.

of

Pharmaceut. 511 (2016) 267-275. [50] A.X. Lu, M.G. Yu, M. Shen, S.Q. Xu, Z.Q. Xu, Y.J. Zhang, et al.,

ro

Preparation of the Auricularia auricular polysaccharides simulated

-p

hydrolysates and their hypoglycaemic effect, Int. J. Biol. Macromol. 106

re

(2018) 1139-1145.

lP

[51] J.Q. Qiu, H. Zhang, Z.Y. Wang, Ultrasonic degradation of

na

polysaccharides from Auricularia auricula and the antioxidant activity of their degradation products, LWT-Food Sci. Technol. 113 (2019)

Jo ur

108266-108274.

[52] Z.J. Wang, J.H. Xie, M.Y. Shen, S.P. Nie, M.Y. Xie, Sulfated modification

of

polysaccharides:

Synthesis,

characterization

and

bioactivities, Trends Food Sci. Tech. 74 (2018) 147-157. [53] M. Kurniasih, Purwati, T. Cahyati, R.S. Dewi, Carboxymethyl chitosan as an antifungal agent on gauze, Int. J. Biol. Macromol. 119 (2018) 166-171. [54] D.S. Lakshmi, N. Trivedi, C.R.K. Reddy, Synthesis and characterization of seaweed cellulose derived carboxymethyl cellulose, 42

Journal Pre-proof

Carbohyd. Polym. 157 (2017) 1604-1610. [55] S.K. Ghosh, A. Das, A. Basu, A. Halder, S. Das, S. Basu, et al., Semi-interpenetrating hydrogels from carboxymethyl guar gum and gelatin for ciprofloxacin sustained release, Int. J. Biol. Macromol. 120 (2018) 1823-1833.

of

[56] B. Bi, H. Liu, W.T. Kang, R.X. Zhuo, X.L. Jiang, An injectable enzymatically crosslinked tyramine-modified carboxymethyl chitin

ro

hydrogel for biomedical applications, Colloid. Surface. B 175 (2019)

-p

614-624.

re

[57] Y.B. Yu, H. Pan, Y.Y. Wang, W. Xiong, Q.T. Zhang, K. Chen, et al.,

lP

New insights into an innovative Auricularia auricular polysaccharide

(2016) 59794-59799.

na

pH-sensitive hydrogel for controlled protein drug delivery, RSC Adv. 6

Jo ur

[58] F. Seidi, R. Jenjob, T. Phakkeeree, D. Crespy, Saccharides, oligosaccharides, and polysaccharides nanoparticles for biomedical applications, J. Control. Release 284 (2018) 188-212. [59] J.Q. Qiu, H. Zhang, Z.Y. Wang, D.D. Liu, S.M. Liu, W. Han, et al., The antitumor effect of folic acid conjugated-Auricularia auricular polysaccharide-cisplatin complex on cervical carcinoma cells in nude mice, Int. J. Biol. Macromol. 107 (2018) 2180-2189. [60] J. Liu, R.Y. Bai, Y.P. Liu, X. Zhang, J. Kan, C.H. Jin, Isolation, structural characterization and bioactivities of naturally occurring 43

Journal Pre-proof

polysaccharide-polyphenolic conjugates from medicinal plants-A review, Int. J. Biol. Macromol. 107 (2018) 2242-2250. [61] D. Kothari, S. Patel, S.K. Kim, Anticancer and other therapeutic relevance of mushroom polysaccharide: A holistic appraisal, Biomed. Pharmacother. 105 (2018) 377-394. [62] Z.C. Ma, J.G. Wang, L.N. Zhang, Y.F. Zhang, K. Ding, Evaluation of

of

water soluble β-D-glucan from Auricularia auricular-judae as potential

ro

anti-tumor agent, Carbohyd. Polym. 80 (2010) 977-983.

-p

[63] J. Yu, R.L. Sun, Z.Q. Zhao, Y.Y. Wang, Auricularia polytricha

re

polysaccharides induce cell cycle arrest and apoptosis in human lung

lP

cancer A549 cells, Int. J. Biol. Macromol. 68 (2014) 67-71.

na

[64] H. Takeuchi, P. He, L.Y. Mooi, Reductive effect of hot-water extracts from woody ear (Auricularia auricula-judae Quel.) on food intake and

Jo ur

blood glucose concentration in genetically diabetic KK-Ay mice, J. Nutr. Sci. Vitaminol. 50 (2004) 300-304. [65] X.Y. Hu, C.G. Liu, X. Wang, D.X. Jia, W.Q. Lu, X.Q. Sun, et al., Hyperglycemic and anti-diabetic nephritis activities of polysaccharides separated from Auricularia auricular in diet-streptozotocin-induced diabetic rats, Exp. Ther. Med. 13 (2017) 352-358. [66] Y. Zheng, L. Bai, Y.P. Zhou, R.S. Tong, M.H. Zeng, X.F. Li, et al., Polysaccharides from Chinese herbal medicine for anti-diabetes recent advances, Int. J. Biol. Macromol. 121 (2019) 1240-1253. 44

Journal Pre-proof

[67] X.X. Wang, Y.F. Lan, Y.F. Zhu, S.S. Li, M. Liu, X.L. Song, et al., Hepatoprotective effects of Auricularia cornea var. Li. polysaccharides against the alcoholic liver diseases through different metabolic pathways, Sci. Rep. 8 (2018) 7574. [68] A.K.T. Chang, R.R. Frias Jr, L.V. Alvarez, U.G. Bigol, J.P.M.D.

of

Guzman, Comparative antibacterial activity of commercial chitosan and chitosan extracted from Auricularia sp., Biocatal. Agr. Biotech. 17 (2019)

ro

189-195.

-p

[69] J.K. Yan, Y.Y, Wang, H.L. Ma, Z.B. Wang, Ultrasonic effects on the

re

degradation kinetics, preliminary characterization and antioxidant

lP

activities of polysaccharides from Phellinus linteus mycelia, Ultrason.

na

Sonochem. 29 (2016) 251-257.

[70] L.N. Zhang, L.Q. Yang, J.H. Chen, Conformational change of the

Jo ur

β-D-glucan of Auricularia auricular-judae in water-dimethylsulfoxide mixtures, Carbohyd. Res. 276 (1995) 443-447. [71] L.M. Xie, M.Y. Shen, Y.Z. Hong, H.D. Ye, L.X. Huang, J.H. Xie, Chemical modifications of polysaccharides and their anti-tumor activities, Carbohyd. Polym. 229 (2020) 115436.

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Figure Legends Fig. 1. Schemes for extractions and purifications of AP from Auricularia [19].

Jo ur

na

lP

re

-p

ro

of

Fig. 2. Schematic structures of AP from Auricularia [6] [8] [37] [66] [68] [22] [19] [25].

46

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Table 1. The polysaccharides of Auricularia from different origins and their chain structures, molecular weight, bioactivities, extraction solvents, and monosaccharide compositions;

Jo ur

na

lP

re

-p

ro

of

Table 2. Summary of the chemical modification methods of AP;

47

Journal Pre-proof

Table 1 Species

Sources

Chain struct ures

MW (kDa )

Main bioactivities

Extraction solvents

Monosaccharide compositions

Reference s

A. auricula

Zhejian g China Hubei China

Unkno wn Unkno wn

3.4× 103 Unkn own

Antioxidant

Distilled water Distilled water

[13]

Hubei China

Unkno wn

Unkn own

Antioxidant

Liaonin g China

Unkno wn

Unknown

Heilong jiang China Heilong jiang China Jinan China Unknow n Liaonin g China

Unkno wn

20.5 ~63. 9 1.4× 102

Mannose:glucose (1.06:1.00) Glucose: rhamnose:arabinos e:Mannose:galacto se (16.7:1.0:1.2:1.0:1. 0) Arabinose:mannos e:galactose:xylose (15.6:1.5:4.8:1.0) Unknown

Unkno wn

Unkn own

[32]

-p

Distilled water

lP

Glucose:galactose:f ucose (50:1:2)

[33]

Antioxidant

Distilled water

Unknown

[28]

Polyethylen e glycol Distilled water Distilled water

Unknown

[23]

Unknown

[16]

Unknown

[30]

Arabinose:xylose: mannose:glucose (1.0:0.4:1.7:1.0) Arabinose:xylose: mannose:glucose:g alactose (1.8:1.2:4.8:1.0:0.4 ) Arabinose:xylose: mannose:glucose

[20]

na

Unknown

Antioxidant

Antioxidant

0.025 M NaOH

Antioxidant

0.025 M NaOH

Heilong jiang China

Unkno wn

Shaanxi China

Unkno wn

Unkn own

[16, 49]

0.025 M NaOH

Unkn own 80.8 1.4~ 3.7× 102 Unkn own

[32]

re

Distilled water

Antioxidant

Jo ur Unkno wn Unkno wn Unkno wn

ro

of

Antioxidant

Unknown

48

[20]

Journal Pre-proof (0.7:0.4:1.4:1.0) Unkno wn

Unkn own

Antioxidant

0.025 M NaOH

Ribose:arabinose:x ylose:fucose:mann ose:glucose:galacto se (2.4:1.6:0.5:2.0:6.2 :1.0:0.4) Arabinose:fucose: mannose:glucose:g alactose (1.17:1.44:3.83:1.0 :0.28) Glucose: galactose: mannose: arabinose: rhamnose (37.5:1.0:4.3:0.9:0. 9) Glucose:mannose:x ylose:fucose (9.0:1.0:1.3:1.3) Unknown

[20]

Zhejian g China

Unkno wn

Unkn own

Antioxidant

0.025 M NaOH

Sichuan China

(1→3)glucos e

27.7

Antioxidant

Distilled water

Hunan China

Unkno wn

Unkn own

Antioxidant

Fujian China

α-glyc osidica lly linked Unkno wn

Unkn own

1.6× 102

Anticoagulan t

0.1 M NaOH

Mannose:glucose:x ylose:hexuronic acid (0.4:0.3:0.3:0.1) Unknown

[21]

Unkno wn

Unkn own

Unknown

0.1 M NaOH

[14-15]

β-D-gl ucan

0.3 ~2.9 × 102 2.1~ 2.2× 103 4.6

Antitumor

70% ethanol

Unknown

[22, 61]

Unknown

0.15 M NaCl

Unknown

[19]

Immunomod ulatory

Submerged culture

Glucose:mannose: galactose:glucuroni c acid (98.9:0.1:0.4:0.6)

[25]

Heilong jiang China Hubei China Hubei China Heilong jiang China

lP

re

-p A. auricula-j udae

na

Decreasing blood lipids

Jo ur

Korea

β-(1→ 3)-D-gl ucan (1→ 4)-α-D -glucos e

[20]

[1]

ro

of

Anhui China

49

Distilled water

Solid-state fermentatio n

[43]

[26]

Journal Pre-proof Heilong jiang China

(1→ 4)-α-D -glucos e

6.7

Immunomod ulatory

Submerged culture

Unknow n Hubei China

Unkno wn β-(1→ 3)-D-gl ucose β-(1→ 3)-D-gl ucose β-(1→ 3)-D-gl ucose Acidic heterop olysacc haride Acidic heterop olysacc haride Unkno wn

2.5× 103 1.2× 103

Unknown

0.15 M NaCl 70% ethanol

1.4× 103

Unknown

Distilled water

2.0× 103

Unknown

88% formic acid

3.0× 102

Unknown

Hubei China

[24]

Glucose

[24]

Glucose

[24]

Distilled water

Xylose:mannose:gl ucose/glucuronic acid (Unknown)

[24]

1 M NaOH

Xylose:mannose:ga lactose:glucose/glu curonic acid (1.8:75.6:1.7:21.1) Glucose:mannose:g alactose (11.4:6.1:1.0) Glucuronic acid: xylose:glucose:ma nnose (1.3:1.0:1.3:4.3) Xylose:mannose:gl ucose:glucuronic acid: (1.0:2.1:1.0:0.6) Xylose:mannose:gl ucose:glucuronic acid: (1.0:4.1:1.3:1.3) Rhamnose:arabinos e:xylose:mannose: glucose:galactose

[24]

ro

of

Glucose:galactose (97.2:2.8)

-p

Unknown

Unkn own

Unknown

Distilled water

(1→3)β-D-gl ucan

1.4× 103

Antitumor

Distilled water

Japan

β-(1→ 3)-gluc ose

Unkn own

Unknown

1M NaOH

Japan

β-(1→ 3)-gluc ose

Unkn own

Unknown

Distilled water

Heilong jiang China

Unkno wn

2.1× 102

Antioxidant

Distilled water

Jo ur

Heilong jiang China Ohita Prefectu re Japan

5.0× 102

[25]

re

Hubei China

lP

Hubei China

na

Hubei China

Unknown

Glucose:mannose: galactose:arabinose :fucose:glucuronic acid: galacturonic acid (97.6:0.1:1.0:0.1:0. 5:0.5:0.2) Unknown

50

[10]

[31]

[6]

[5]

[5]

[35]

Journal Pre-proof

Jiangsu China

Korea

0.05 M NaOH

Unkn own Unkn own

Anti-hyperch olesterolemic Antitumor

Distilled water 95% ethanol

Unknown

[27]

Unknown

[62]

2.6× 102

Antitumor

Distilled water

Glucose

[8]

Arabinose:mannos: glucose:galactose (1.00:1.33:1.06:1.2 3) Rhamnose:fucose:a rabinose:xylose:ma nnose:galactose:glu cose (1.0:3.5:1.5:2.4:51. 2:32.9:7.3) Mannose:xylose (1.00:1.03) Mannose:galactose :glucose:glucuronic acid (3.5:2.1:0.6:2.1) Mannose:galactose :glucose:glucuronic acid (2.5:2.1:0.2:2.4)

[40]

-p

ro

of

Antitumor

re

β-(1→ 3)-D-gl ucan and β-(1→ 3,6)-Dglucop yranos yl Unkno wn

[37]

1.2× 103

21.2

lP

Beijing China Heilong jiang China Hangzh ou China

1, 3-β-glu can,1, 4-α-glu can,1, 3-α-glu can, Unkno wn Unkno wn

Antioxidant

na

Zhejian g China

Jo ur

A. polytricha

(0.2:2.6:0.4:3.6:1.0 :0.4) Glucan

Distilled water

Unkno wn

Unkn own

Decreasing blood lipids

Submerged culture

Sichuan China Unknow n

Unkno wn Unkno wn

1.1× 102 14.0

Antitumor Antioxidant

Distilled water Distilled water

Unknow n

Unkno wn

27.0

Antioxidant

Distilled water

51

[44]

[42] [45]

[45]

Journal Pre-proof Antioxidant

Distilled water

Unknow n

Unkno wn

46.0

Antioxidant

Distilled water

Beijing China

α-confi guratio n

Unkn own

Antioxidant and hepatoprotec tive

Distilled water

Beijing China

α-confi guratio n

Unkn own

Antioxidant and hepatoprotec tive

Distilled water

Manila Philippi nes

Unkno wn

Unkn own

Antibacterial

Mannose:galactose :glucose (4.2:2.3:1.1) Mannose:galactose :glucose:glucuronic acid (3.3:1.7:0.4:1.7) Fucose:arabinose:x ylose:mannose:gala ctose:glucose (5.9:1.0:21.1:6.4:2. 3:53.7) Fucose:ribose:xylo se:mannose:galacto se:glucose (8.8:1.0:26.4:8.2:1 0.0:58.1) Unknown

[45]

[45]

[66]

[66]

-p

ro

of

43.0

4 M NaOH

re lP na

A. sp.

Unkno wn

Jo ur

A. cornea var. Li.

Unknow n

52

[67]

Journal Pre-proof

Table 2 Classification of modification

Method

Biological activity

The characteristi c absorption peak

References

Physicochemical degradation Sulfation

Solution plasma process Chlorosulfonic acid-pyridine method and sulfur trioxide-pyridine method Chloroacetic acid-NaOH method

Antioxidant

-

[29-30]

Carboxymethylation

Hydrolysis

Complexation

r P

New peaks at 1258, 1235, 819, and 810 cm-1

[12, 36, 41]

[13, 48]

Antioxidant and hypoglycaemic

New peaks at 1606, 1424, and 1324 cm-1 -

Antitumor

-

[14, 16, 57]

l a

rn

Antioxidant and radioprotective

u o

J

Sulfuric acid/hydrochloric acid-hydrolysis method One pot method and coacervation method

o r p

e

Antiviral, antioxidant, and immuno-enhancing

f o

53

[33, 50]

Journal Pre-proof

Drug-loaded nanoparticles

Polyelectrolyte coacervation method and self-assembled organic solvent evaporation method

Antitumor

-

[14, 17, 49]

f o

l a

e

o r p

r P

n r u

o J

54

Journal Pre-proof

Highlights 1.Research findings during the past decades have been summarized, including the extraction and purification techniques, modifications, structural characteristics, and biological activities of AP. 2.The paper gives a comprehensive insight into extraction and

of

purification techniques, chemical structures and biological activities of

ro

AP.

-p

3.The paper provides knowledge that will lead to more development and

Jo ur

na

lP

re

applications of AP.

55

Figure 1

Figure 2