- Email: [email protected]
The biocontrol of postharvest decay of table grape by the application of kombucha during cold storage
Scientia Horticulturae 253 (2019) 134–139
Contents lists available at ScienceDirect
Scientia Horticulturae journal homepage: www.elsevier.com/locate/scihorti
The biocontrol of postharvest decay of table grape by the application of kombucha during cold storage
T
⁎
Xian Zhoua, Junping Tana, Yuanyuan Goua, Yongling Liaoa, Feng Xua, , Gang Lia, Jie Caoa, ⁎ Jinglei Yaoa, Jiabao Yea, Ning Tangb, Zexiong Chenb, a b
College of Horticulture and Gardening, Yangtze University, Jingzhou, 434025, Hubei, China Research Institute for Special Plants, Chongqing University of Arts and Sciences, ChongQing, 402160, China
A R T I C LE I N FO
A B S T R A C T
Keywords: Table grape Kombucha Fruit quality Decay Cold storage Antioxidant enzyme
Grapes are susceptible to fungal infection and decay after harvest. The objective of this study was to investigate the effects of kombucha on postharvest fresh-keeping in table grape (Vitis vinifera cv. Fujiminori). Here, we studied the effects of kombucha on the fruit quality and antioxidant system of grape at 4 °C storage. The fruits of grape were dipped into water or kombucha for 15 min and then stored at 4 °C. The physical parameters of fruits, such as the good fruit rate, fruit hardness, contents of soluble solid, ascorbic acid (Vit C) and malodialdehyde (MDA), and activities of the antioxidant enzymes were measured during storage. The application of kombucha reduced deterioration of table fruit during cold storage. The kombucha treatment also delayed the decrease in fruit hardness, soluble solid and Vit C contents, and inhibited the MDA accumulation in grape during storage. Furthermore, fruit treated with kombucha showed significantly higher activities of polyphenol oxidase, peroxidase, catalase and superoxide dismutase with a significantly lower MDA accumulation at the late stage of storage compared the control. Our findings suggested that kombucha application was useful in inhibiting postharvest decay of table grape fruit and appeared to have potential for commercial application to store table grape at cold storage.
1. Introduction Grape is an important cash crop that is widely distributed all over the world. Grape berries are characterized by their bright color, juicy taste, and high nutrient and carbohydrate contents. They are also rich in vitamins, anthocyanins, carotenoids, and several antioxidants. These substances can effectively remove free radicals from the body and delay senility (Zhou and Raffoul, 2012; Ye et al., 2016). In addition, grapes contain a variety of bioactive ingredients that can reduce the risks of cardiovascular disease, diabetes, and cancer in populations that consume grapes. Grape berries are easily dehydrated during storage and are susceptible to rot caused by fungal infection. Dehydration and rotting affect the quality of grape berries (de Sousa et al., 2013). Therefore, in this work, we aimed to solve the problems associated with the storage and preservation of grape berries. Grape preservatives studied at home and abroad are mainly classified as chemical, physical, or biological preservatives. (SO3)2−, chitosan /PVA with salicylic acid, and polyamines are applied as chemical preservatives (Champa et al., 2015; Xue and Yi, 2017; Loˊay and ELBoray, 2018). Ultraviolet light type C radiation and CO2 treatment are ⁎
examples of physical preservatives (Maurer et al., 2017; Cefola et al., 2018). Aureobasidium pullulans (Mari et al., 2012), Cryptococcus laurenti (Meng et al., 2010), and Hanseniaspora uvarum (Qin et al., 2015) are used as biological preservatives. (SO3)2− is the most commonly used chemical preservative. It increases L-phenylalanin ammonia-lyase (PAL) and polyphenol oxidase (PPO) activities by releasing SO2. It enhances grape disease resistance and prolongs storage life by activating defense responses related to secondary metabolism and PR proteins (Xue and Yi, 2017). However, low doses of (SO3)2− have poor preservative effects because they release insufficient amounts of SO2, and excessively high doses of (SO3)2− will bleach grape berries. The spots caused by (SO3)2− bleaching affect the appearance of grapes and are harmful to the health of consumers (Smilanick et al., 1990). CO2 treatment is currently the most commonly used physical preservative method. Treatment with 10% CO2 can maintain the sensory quality and nutritional quality of grapes and delay the senescence of grape berries. Extremely high CO2 concentrations, however, will intensify anaerobic respiration; produce harmful substances, such as ethanol and acetaldehyde; promote the rapid propagation of some anaerobic microorganisms; and cause fruit dehydration, alcoholization, and blackcore
Corresponding authors. E-mail addresses: [email protected] (F. Xu), [email protected] (Z. Chen).
https://doi.org/10.1016/j.scienta.2019.04.025 Received 31 December 2018; Received in revised form 20 March 2019; Accepted 11 April 2019 0304-4238/ © 2019 Elsevier B.V. All rights reserved.
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
grape fruit every storage period over initial weight of grape fruit before storage, expressed as a percentage. Fruit hardness was determined by using the fruit hardness tester referring method of Segade et al (2013). The assay of soluble solid content were carried out using a refractiometer (ATAGO China Guangzhou Co., ltd, Japan). Three-hundred μL juice of broken grape was placed on prism of the instrument to reading (Mariani et al., 2014). The content of Vit C was measured using the methods described by Rekha et al. (2012).
(Cefola et al., 2018). Biological preservatives are easy to cultivate, environmentally friendly, and nontoxic. They exert their preservative effects by competing with harmful microorganisms for space and nutrients (Droby et al., 2009). For example, the binding between C. laurentii and chitosan in grape berries drastically increases PAL and PPO activities, improves disease resistance, and reduces decay rate (Meng et al., 2010). The cell suspensions of Candida oleophila can induce the accumulation of chitinase, β-1, 3-endoglucanase, and phytoalexins and improve the control of Penicillium digitatum infections in grapefruit (Droby et al., 2002). A. pullulans, Metschnikowia sp. and Pseudozyma fusiformata exert a strong inhibitory effect on the brown rot of peach (Zhang et al., 2010). Kombucha is produced by fermenting tea using a symbiotic culture of bacteria and yeast (Dufresne and Farnworth, 2000). Kombucha is a slightly sweet and slightly acidic drink. It can prevent various cancers and cardiovascular and cerebrovascular diseases, promote liver function, and stimulate the immune system (Malbaša et al., 2011). It is produced through the fermentation of tea sugar water by microzymes, acetic acid bacteria, and lactic acid bacteria (Chen and Liu, 2000). Kombucha has an inhibitory effect on Escherichia coli, Bacillus subtilis, and Staphylococcus aureus (Sreeramulu et al., 2000). Given these characteristics, it can be speculated that kombucha is a potential natural pollution-free food preservative that can be used as an alternative to chemical preservatives in fruit. However, the application of kombucha in fruit and vegetable preservation has not been studied. In this work, we investigated the effect of treatment with kombucha on the postharvest decay, fruit quality and antioxidant enzyme activities of table grape during storage at 4 °C. Our study should be helpful for further development of commercial and non-chemical postharvest technology for quality maintenance and shelf life extension of table grape.
2.3. Assay of malondialdehyde (MDA) content and antioxidant enzyme activity Malondialdehyde (MDA) content was measured by thiobarbituric acid method (Heath and Packer, 1968). In the method, the reaction produces a colored trimethyl compound with different absorbance values at different wavelengths of 450 nm, 532 nm, and 600 nm. MDA content was calculated according the following formula: C (μmol/ L) = 6.45 (A532-A600) - 0.56 A450. Superoxide dismutase (SOD) activity was measured by the method of nitrotetrazolium blue chloride (NBT) described by (Cao et al., 2011). One unit of SOD activity was defined as inhibition of 50% NBT photoreduction. Peroxidase (POD) activity was assayed using guaiacol oxidation method, one unit of peroxidase activity was defined as the amount of enzyme which change the absorbance value of 0.01 per minute (Ciou et al., 2011). Catalase (CAT) activity was assayed by ultraviolet spectrophotometry (Aebi, 1984). Polyphenol oxidase (PPO) activity was assayed using the catechol method, one unit was defined as changing 0.01 for 1 ml per minute (Queiroz et al., 2011). 2.4. Statistical analysis
2. Materials and methods
All data presented were means of 6 replicates with standard errors (SD). Data were subjected to analysis of variance, and means were compared using least significance difference (LSD) test using SPSS 10.0 for Windows (SPSS Inc., IL, USA,). Difference at p < 0.05 indicates significant.
2.1. Preparation of kombucha, fruit materials and treatments The kombucha solution were preserved in our laboratory. The kombucha was prepared by the following method. Mixture about 6 l was boiled for 10 min, of which ratio was boiled water 0.5 l, sucrose 50 g (g) and black tea 5 g. Then, the mixture was dispensed into 6 glass jars (1 l) by funnel filtered to remove tea grounds. Finally, the kombucha solution inoculated together into the above liquid. The liquid was fermented for 2 weeks under 28 °C. Kombucha was prepared successfully and the filtrate was the kombucha fermentation broth used to treat table grape fruits. The table grape (Vitis vinifera cv. Fujiminori) were harvested on 5th August in Yangtze University deciduous fruit base, Jingzhou, China (around N30.35, E112.14). Harvested grape clusters were dipped in water to clean the surfaces and then selected based on uniformity of size, color, and disease-free. The selected fruits were divided into two groups. One group was immersed in distilled water for 15 min as control and the other group was dipped into kombucha fermentation broth for 15 min as treatment. The control and treated grape fruits were airdried, then packed into plastic polyethylene bags, and then stored for 33 days at 4 °C storage and 70–80% relative humidity. Grape fruit was sampled at the 0 st, the 3rd, the 6th, the 9th, the 12th, the 15th, the 18th, the 21th, the 24th, the 27th, the 30th, the 33th day after treatments, respectively. Each treatment consisted of six replication with ten table grape berries per replication. The assays were performed at least three times.
3. Results 3.1. Effect of kombucha on good fruit rate, water loss rate and fruit firmness in table grape The rate of good fruit is defined as the percentage of fruits without mechanical injury, insect damage, and disease spots as identified through naked-eye observation. As shown in Fig. 1A, the rate of good fruits decreased with the prolongation of storage time. The rate of good fruits treated with kombucha was significantly higher than that in control during storage. The rates of good fruits in the treatment and control groups were 42.5% and 24.5%, respectively, after 33 d of storage. This result indicates that kombucha exerted a preservative effect on the treated grapes. As shown in Fig. 1B, the weight loss rate of grapes increased with the extension of storage time. The greatest difference between the weight losses of the control and treatment groups was observed after 33 d of storage. The treatment reduced the mass loss of the fruits in 50% compared with the control. The hardness of grape berries in the treatment group and the control group decreased with storage time (Fig. 1C). The hardness of grape berries treated with kombucha was consistently higher than that of non-kombucha-treated grape berries. After 33 d of storage, the hardness of grape berries in the treatment group (1.6 N) was 3.4 times of that of grape berries in the control group (0.48 N).
2.2. Measurement of good fruit rate, weight loss, fruit hardness, soluble solid content (SSC), ascorbic acid (Vit C)
3.2. Effects of kombucha on soluble solid and Vit C in table grapes
Good fruit rate was evaluated by number of good grape fruit every storage period compared total number of grape fruit before storage, expressed as a percentage. Weight loss was calculated by weight change
The soluble solid contents of the control and treatment fruit first 135
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
control group first rapidly increased and then slowly decreased. In particular, the soluble solid content of the treatment group was significantly higher than that of the control group during the later stages of storage. As shown in Fig. 3B, the Vit C contents of the control and treatment groups decreased rapidly during the early stages of storage and slowly decreased during the later stages of storage. On 33 d of storage, the Vit C content of the treatment group was 5.43 mg/100 g, which was significantly higher than that of the control group (4.34 mg/ 100 g). 3.3. Effects of kombucha on the content of MDA in table grapes MDA is used as an indicator of the degree of lipid peroxidation in the cell membranes of fruits. The MDA contents of the treatment and control groups increased. The MDA content of the treatment group was consistently significantly lower than that of the control group during storage (Fig. 4). The MDA content of the control increased slowly from 3rd to 21th and the treatment group increased slowly from 3rd to 24th. However, MDA content of the control and treatment group rased rapidly. MDA content of the treatment was lower than the control until 33rd. 3.4. Effects of kombucha on antioxidant enzyme activities in table grapes As shown in Fig. 5A, PPO activities in the control and treatment groups increased and did not significantly differ during the early stages of storage (0–15 d). The increase in PPO activity after 15 d of storage was more rapid in the control than that in the treatment. PPO activity in treatment group was significantly lower than that in the control group from 15 to 33 d of storage (p < 0.05). POD activities in the treatment and control groups increased during storage (Fig. 5B). After 24 d of storage, POD activity in the kombucha treatment was always higher than that in the control group. Catalase (CAT) activities in the treatment and control groups first decreased and then increased (Fig. 5C) and reached the lowest values of 3.65 and 2.45U/g−1min – 1, respectively, on 18 d of storage. CAT activity in the treatment group was higher than that in the control group throughout the entirety of the storage period. As shown in Fig. 5D, SOD activity in the treatment and control groups first increased and then decreased with the prolongation of storage time and reached the maximum values of 57.43 and 50.13 U/ g, respectively, on 24 d of storage. During the whole storage period, SOD activity in the treatment group was significantly higher than that in the control group (p < 0.05). The above results show that treatment with kombucha can prolong the freshness of grapes during storage by attenuating active oxygen production. Kombucha reduces active oxygen production by increasing the activity of antioxidant enzymes. 4. Discussion Grape berries are non-respiratory climacteric fruits with high water content. They undergo a series of postharvest physiological and biochemical reactions that increase their susceptibility to pathogen-induced processes, such as decay, drying, and wilting (de Sousa et al., 2013). Changes in respiration and transpiration rates mainly cause the postharvest water loss of grape berries (Min et al., 2001). Loˊay and Dawood (2017) found that chitosan can reduce the rate of water and weight loss of grape berries by forming films that inhibit respiration on grape skins. In this study, we found that kombucha can reduce the water loss rate of grapes, similar to the effect of chitosan on grape. Kombucha promotes water retention and decreases water loss rate by forming a film on grape skins (Fig. 2). This film ultimately prolongs the shelf life of grapes by inhibiting water evaporation, reducing respiratory rate, and preventing infection by pathogenic bacteria. The main components of the fruit cytoderm include insoluble pectin, cellulose, and hemicellulose. These substances are closely related to the hardness of fruits and are degraded by pectinase and
Fig. 1. Effects of kombucha on good fruit rate (A), weight loss (B) and fruit hardness(C) of grape. The data are displayed with mean ± SD (bars) of 6 replication.
increased and then decreased. The soluble solid contents of grape berries in the control and treatment groups peaked after 9 d and 21 d of storage, respectively (Fig. 3A). During 3–12 d of storage, the soluble solid content of the control group was higher than that of the treatment group. The greatest difference between the soluble solid content of the two groups was observed on 9 d of storage. The soluble solid content of the treatment group was higher than that of the control group beginning on 15 d of storage onwards. To summarize, the soluble solid content of the treatment group first slowly increased and then slowly decreased during storage. By contrast, the soluble solid content of the 136
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
Fig. 2. The grape was affected by water (A, C) and kombucha(B, D).
Fig. 4. Effects of kombucha on MDA content in grape fruit. The data are displayed with mean ± SD (bars) of 6 replication.
salicylic acid can prevent fruit hardness from decreasing and prolong fruit storage life by decreasing the activity of cellulase, polygalacturonase, and xylanase and decelerating the degradation of cellulose, hemicellulose, and pectin (Loˊay and EI-Khateeb, 2018). Like chitosan /PVA with salicylic acid, our data revealed that kombucha decelerates fruit softening by inhibiting the activities of degradative enzymes in the cytoderm of grape berries (Champa et al., 2015). The physiological mechanism related to this effect requires further study. Vit C, soluble solids and anthocyanins are important indicators used for evaluating fruit quality (Ye et al., 2017). These components also participate in reactive oxygen scavenging and physiological responses by acting as the cofactors of various enzymes (Fransson and Mani, 2007). Vit C can prevent the browning of fruit by inhibiting the PPOcatalyzed formation of phenols from quinones (Tate et al., 1964). It exerts a strong concentration-dependent inhibitory effect on PPO and POD activities. This study showed that kombucha can effectively inhibit the postharvest Vit C degradation of grapes and promote the accumulation of soluble solids. Taken that sugar accumulation in fruits can increase Vit C content (Massot et al., 2010), it can be concluded that Kombucha treatment may increase the content of soluble solids in the
Fig. 3. Effects of kombucha on content of soluble solid content (SSC) (A) and ascorbic acid (Vit C) (B) in grape fruit. The data are displayed with mean ± SD (bars) of 6 replication.
hemicellulase during fruit maturation. The degradation of pectin and hemicellulose results in pulp tissue softening and decreases fruit hardness (Deng et al., 2013). Postharvest treatment with chitosan/PVA with 137
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
Fig. 5. Effects of kombucha on polyphenol oxidase (PPO) activity (A), peroxidase (POD) activity (B), catalase (CAT) activity (C) and superoxide dismutase (SOD) activity (D) in grape fruit. The data are displayed with mean ± SD (bars) of 6 replication.
that treatment with kombucha can increase POD activity in grapes. Our finding is consistent with that of (Khan et al., 2010) that treatment with Rhodotorula glutinis can maintain peach fruit quality by inducing host POD activity. Therefore, kombucha may improve quality fruit by increasing POD enzyme scavenging or preventing reactive oxygen species production. At the same time, it participates in the synthesis of phenolic compounds, phytoprotective substances, lignin, and other stress-resistant substances in fruits and vegetables. The presence of these components ultimately maintains fruit quality by delaying fruit softening and improving disease resistance. Moreover, POD is related to fruit color, flavor, and nutrient formation (Ferrer et al., 2005; Zhong et al., 2005, 2007). In addition to POD, SOD and CAT are important enzymes in plant resistance physiology. SOD is a natural free radical scavenger in biological organisms. It can catalyze O2− dismutation, which yields H2O2 and O2 as products (Van Camp et al., 1996). CAT alleviates the toxicity of H2O2 to plant tissues by scavenging H2O2 into H2O and O2. Our results showed that the activity of SOD, which scavenges O2−, increased during the early stage of treatment with kombucha. SOD activity gradually declined in the late stage of treatment. This decline may be attributed to the coordination of its own enzyme system. CAT activity, however, slightly decreased at early stage of storage and then subsequently decreased at late stage of storage. This increase may be related to the constant resistance response of grapes. The activities of the antioxidant enzymes (POD, SOD, and CAT) in grapes increased after treatment with kombucha, indicating that kombucha treatment can improve the antioxidant capacity of grape berries and has potential applications as a preservative.
form of soluble sugar during the early stages of storage. In addition, the higher Vit C content of the treatment group than that of the control group may be attributed to the transformation of some soluble solids into Vit C. MDA is an important indicator applied for evaluating the stability of plant membrane systems. Membrane system stability is closely related to plant stress resistance (Lyons, 1973). Its strong reactions with various cellular components severely damage enzymes and membranes and reduce membrane resistance and fluidity. These effects eventually cause the destruction of membrane structure and physiological integrity (Scandalios, 1993). Changes in MDA content reflect the degree of cellular membrane lipid peroxidation (Juan et al., 2011). We demonstrated that MDA content, which reflects the degree of membrane lipid peroxidation in fruits, gradually increased as grape ripening and senescence progressed during storage. Consistent with the findings of a study showing that treatment with Pichia guilliermondii and hot air can reduce membrane lipid peroxidation in peach (Zhao et al., 2019), treatment with kombucha can reduce membrane lipid peroxidation during fruit storage. Thus, our results further indicated that kombucha treatment can prevent the postharvest deterioration of cell membrane structure and attenuate reductions in nutrient content and flavor quality by reducing MDA accumulation. Antioxidant enzymes, such as SOD, POD, and CAT, play important roles in scavenging reactive oxygen species, reducing membrane lipid peroxidation levels, and improving plant stress adaptability (Ye et al., 2016; Yang et al., 2016). POD, an important defensive enzyme in the phenylpropane metabolic pathway, is closely related to the disease resistance of plants. It helps catalyze lignin production and enhances cell structural stability (Mohammadi and Kazemi, 2002). It is also a key enzyme in fruit refrigeration and browning (Richard-Forget and Gauillard, 1997). Browning can reduce nutritional quality and consumer acceptance by changing fruit traits (Ciou et al., 2011). We found
5. Conclusions In conclusion, our results provide evidence of the ability of kombucha to reduce of postharvest decay and maintain the fruit quality in 138
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
table grape during cold storage. Kombucha application prevent weight loss and fruit softening, while improving soluble solid and Vit C contents in table grape during cold storage. Kombucha increase antioxidant enzyme (POD, SOD, and CAT) activity and thus delay cellular membrane lipid peroxidation. Our findings suggested that the kombucha treatment is a safe and commercial postharvest mean for maintaining quality and prolonging storage life of harvested table grapes.
1727–1731. https://doi.org/10.1016/j.foodchem.2011.02.048. Mari, M., Martini, C., Spadoni, A., Rouissi, W., Bertolini, P., 2012. Biocontrol of apple postharvest decay of Aureobsidium pullulans. Postharvest Biol. Tec. 73, 56–62. https://doi.org/10.1016/j.postharvbio.2012.05.014. Mariani, N.C.T., da Costa, R.C., de Lima, K.M.G., Nardini, V., Júnior, L.C.C., de Almeida Teixeira, G.H., 2014. Predicting soluble solid content in intact jaboticaba [Myrciaria jaboticaba (Vell.) O. Berg] fruit using near-infrared spectroscopy and chemometrics. Food Chem. 159, 458–462. https://doi.org/10.1016/j.foodchem.2014.03.066. Massot, C., Génard, M., Stevens, R., Gautier, H., 2010. Fluctuations in sugar content are not determinant in explaining variations in vitamin C in tomato fruit. Plant Physiol. Biochem. 48, 751–757. https://doi.org/10.1016/j.plaphy.2010.06.001. Maurer, L.H., Bersch, A.M., Santos, R.O., Trindade, S.C., Costa, E.L., Peres, M.M., 2017. Postharvest UV-C irradiation stimulates the non-enzymatic and enzymatic antioxidant system of ‘Isabel’ hybrid grapes (Vitis labrusca×Vitis vinifera L.). Food Res. Int. 102, 738–747. https://doi.org/10.1016/j.foodres.2017.09.053. Meng, X.H., Qin, G.Z., Tian, S.P., 2010. Influences of preharvest spraying Cryptococcus laurentii, combined with postharvest chitosan coating on postharvest diseases and quality of table grapes in storage. LWT-Food Sci. Technol. 43, 596–601. https://doi. org/10.1016/j.lwt.2009.10.007. Min, Z., Chunli, L., Yanjun, H., Qian, T., Haiou, W., 2001. Preservation of fresh grapes at ice-temperature-high-humidity. Int. Agrophys. 15, 139–143. Mohammadi, M., Kazemi, H., 2002. Changes in peroxidase and polyphenol oxidase activities in susceptible and resistant wheat heads inoculated with Fusarium graminearum and induced resistance. Plant Sci. 162, 491–498. https://doi.org/10.1016/ S0168-9452(01)00538-6. Qin, X., Xiao, H., Xue, C., Yu, Z., Yang, R., Cai, Z., Si, L., 2015. Biocontrol of gray mold in grapes with the yeast Hanseniaspora uvarum, alone and in combination with salicylic acid or sodium bicarbonate. Postharvest Biol. Tec. 100, 160–167. https://doi.org/10. 1016/j.postharvbio.2014.09.010. Queiroz, C., da Silva, A.J.R., Lopes, M.L.M., Fialho, E., Valente-Mesquita, V.L., 2011. Polyphenol oxidase activity, phenolic acid composition and browning in cashew apple (Anacardium occidentale, L.) after processing. Food Chem. 125, 128–132. https://doi.org/10.1016/j.foodchem.2010.08.048. Rekha, C., Poornima, G., Manasa, M., Abhipsa, V., Devi, J.P., Kumar, V.H.T., Kekuda, T.R.P., 2012. Ascorbic acid, total phenol content and antioxidant activity of fresh juices of four ripe and unripe citrus fruits. Chem. Sci. Trans. 1, 303–310. https://doi. org/10.7598/cst/2012.182. Richard-Forget, F.C., Gauillard, F.A., 1997. Oxidation of chlorogenic acid, catechins, and 4-methylcatechol in model solutions by combinations of pear (Pyrus communis cv. Williams) polyphenol oxidase and peroxidase: a possible involvement of peroxidase in enzymatic browning. J. Agric. Food Chem. 45, 2472–2476. https://doi.org/10.1021/ jf970042f. Scandalios, J.G., 1993. Oxygen stress and superoxide dismutases. Plant Physiol. 101 (1), 7–12. https://doi.org/10.1104/pp.101.1.7. Segade, S.R., Giacosa, S., Torchio, F., Palma, L.D., Novello, V., Gerbi, V., Rolle, L., 2013. Impact of different advanced ripening stages on berry texture properties of ‘Red Globe’ and ‘Crimson Seedless’ table grape cultivars (Vitis vinifera, L.). Sci. Hortic. 160, 313–319. https://doi.org/10.1016/j.scienta.2013.06.017. Smilanick, J.L., Harvey, J.M., Hartsell, P.L., Henson, D.J., Harris, C.M., Fouse, D.C., Assemi, M., 1990. Influence of sulfur dioxide fumigant dose on residues and control of postharvest decay of grapes. Plant Dis. 74, 418–421. https://doi.org/10.1094/PD74-0418. Sreeramulu, G., Zhu, Y., Knol, W., 2000. Kombucha fermentation and its antimicrobial activity. J. Agric. Food Chem. 48, 2589–2594. https://doi.org/10.1021/jf991333m. Tate, J.N., Luh, B.S., York, G.K., 1964. Polyphenol oxidase in Barlett pears. J. Food Sci. 29, 829–836. https://doi.org/10.1111/j.1365-2621.1964.tb00456.x. Van Camp, W., Capiau, K., Van Montagu, M., Inze, D., Slooten, L., 1996. Enhancement of oxidative stress tolerance in transgenic tobacco plants overproducing Fe-superoxide dismutase in chloroplasts. Plant Physiol. 112, 1703–1714. https://doi.org/10.1104/ pp.112.4.1703. Xue, M., Yi, H., 2017. Induction of disease resistance providing new insight into sulfur dioxide preservation in Vitis vinifera L. Sci. Hortic. 225, 567–573. https://doi.org/10. 1016/j.scienta.2017.07.055. Yang, F., Xu, F., Wang, X.H., Liao, Y.L., Chen, Q.W., Meng, X.X., 2016. Characterization and functional analysis of a MADS-box transcription factor gene (GbMADS9) from Ginkgo biloba. Sci. Hortic. 212, 104–114. https://doi.org/10.1016/j.scienta.2016.09. 042. Ye, J.B., Chen, Q.W., Tao, T.T., Wang, G., Xu, F., 2016. Promotive effects of 5-aminolevulinic acid on growth, photosynthetic gas exchange, chlorophyll, and antioxidative enzymes under salinity stress in Prunnus persica (L.) Batseh seedling. Emir. J. Food Agric. 786–795. https://doi.org/10.9755/ejfa.2016-06-647. Ye, J.B., Xu, F., Wang, G.Y., Chen, Q.W., Tao, T.T., Song, Q.L., 2017. Molecular cloning and characterization of an anthocyanidin synthase gene in Prunus persica (L.) batsch. Not. Bot. Hortic. Agrobo. 45 (1), 28–35. https://doi.org/10.15835/nbha45110546. Zhang, D., Spadaro, D., Garibaldi, A., Gullino, M.L., 2010. Selection and evaluation of new antagonists for their efficacy against postharvest brown rot of peaches. Postharvest Biol. Techcnol. 55, 174–181. https://doi.org/10.1016/j.postharvbio. 2009.09.007. Zhao, Y., Li, Y., Yin, J., 2019. Effects of hot air treatment in combination with Pichia guilliermondii on postharvest preservation of peach fruit. J. Sci. Food Ag. 99 (2), 647–655. https://doi.org/10.1002/jsfa.9229. Zhong, K., Hu, X., Zhao, G., Chen, F., Liao, X., 2005. Inactivation and conformational change of horseradish peroxidase induced by pulsed electric field. Food Chem. 92, 473–479. https://doi.org/10.1016/j.foodchem.2004.08.010. Zhong, K., Wu, J., Wang, Z., Chen, F., Liao, X., Hu, X., Zhang, Z., 2007. Inactivation kinetics and secondary structural change of PEF-treated POD and PPO. Food Chem. 100 (1), 15–123. https://doi.org/10.1016/j.foodchem.2005.09.035. Zhou, K., Raffoul, J.J., 2012. Potential anticancer properties of grape antioxidants. J. Oncol. 2012, 803294. https://doi.org/10.1155/2012/803294.
Acknowledgement This study was supported by the Science and Technology Development Project of Jingzhou City (2011CB36). References Aebi, H., 1984. Catalase in vitro. Methods Enzymol. 105, 121–126. https://doi.org/10. 1016/S0076-6879(84)05016-3. Cao, S., Hu, Z., Zheng, Y., Yang, Z., Lu, B., 2011. Effect of BTH on antioxidant enzymes, radical-scavenging activity and decay in strawberry fruit. Food Chem. 125, 145–149. https://doi.org/10.1016/j.foodchem.2010.08.051. Cefola, M., Damascelli, A., Lippolis, V., Cervellieri, S., Linsalata, V., Logrieco, A.F., Pace, B., 2018. Relationships among volatile metabolites, quality and sensory parameters of ‘Italia’ table grapes assessed during cold storage in low or high CO2 modified atmospheres. Postharvest Biol. Technol. 142, 124–134. https://doi.org/10.1016/j. postharvbio.2017.09.002. Champa, W.A.H., Gill, M.I.S., Mahajan, B.V.C., Bedi, S., 2015. Exogenous treatment of spermine to maintain quality and extend postharvest life of table grapes (Vitis vinifera L.) cv. Flame Seedless under low temperature storage. LWT-Food Sci. Technol. 60, 412–419. https://doi.org/10.1016/j.lwt.2014.08.044. Chen, C., Liu, B.Y., 2000. Changes in major components of tea fungus metabolites during prolonged fermentation. J. Appl. Microbiol. 89, 834–839. https://doi.org/10.1046/j. 1365-2672.2000.01188. Ciou, J.Y., Lin, H.H., Chiang, P.Y., Wang, C.C., Charles, A.L., 2011. The role of polyphenol oxidase and peroxidase in the browning of water caltrop pericarp during heat treatment. Food Chem. 127, 523–527. https://doi.org/10.1016/j.foodchem.2011.01. 034. de Sousa, L.L., de Andrade, S.C.A., Athayde, A.J.A.A., de Oliveira, C.E.V., de Sales, C.V., Madruga, M.S., de Souza, E.L., 2013. Efficacy of Origanum vulgare L. and Rosmarinus officinalis L. essential oils in combination to control postharvest pathogenic Aspergilli and autochthonous mycoflora in Vitis labrusca L. (table grapes). Int. J. Food Microbiol. 165, 312–318. https://doi.org/10.1016/j.ijfoodmicro.2013.06.001. Deng, J., Liu, H.M., Zhang, N.X., Yan, Y., Li, X.Z., 2013. Effects of postharvest calcium and heat treatment on cell wall material metabolism during grapefruit storage. Nor. Hortic 000123-129. Droby, S., Vinokur, V., Weiss, B., Cohen, L., Daus, A., Goldschmidt, E.E., Porat, R., 2002. Induction of resistance to Penicillium digitatum in grapefruit by the yeast biocontrol agent Candida oleophila. Phytopathology 92, 393–399. https://doi.org/10.1094/ phyto.2002.92.4.393. Droby, S., Wisniewski, M., Macarisin, D., Wilson, C., 2009. Twenty years of postharvest biocontrol research: is it time for a new paradigm. Postharvest Biol. Technol. 52, 137–145. https://doi.org/10.1016/j.postharvbio.2008.11.009. Dufresne, C., Farnworth, E., 2000. Tea, kombucha, and health: a review. Food Res. Int. 33, 409–421. https://doi.org/10.1016/S0963-9969(00)00067-3. Ferrer, A., Remón, S., Negueruela, A.I., Oria, R., 2005. Changes during the ripening of the very late season Spanish peach cultivar Calanda: feasibility of using CIELAB coordinates as maturity indices. Sci. Hortic. 105, 435–446. https://doi.org/10.1016/j. scienta.2005.02.002. Fransson, L.A., Mani, K., 2007. Novel aspects of vitamin C: how important is glypican-1 recycling. Trends Mol. Med. 13, 143–149. https://doi.org/10.1016/j.molmed.2007. 02.005. Heath, R.L., Packer, L., 1968. Photoperoxidation in isolated chloroplasts: I. Kinetics and stoichiometry of fatty acid peroxidation. Arch. Biochem. Biophys. 125, 189–198. https://doi.org/10.1016/0003-9861(68)90654-1. Juan, K.A.N., Wang, H.M., Jin, C.H., 2011. Changes of reactive oxygen species and related enzymes in mitochondrial respiration during storage of harvested peach fruits. Agric. Sci. China 10, 149–158. https://doi.org/10.1016/S1671-2927(11)60317-9. Khan, Z.U., Ahmad, S., Hagen, F., Fell, J.W., Kowshik, T., Chandy, R., Boekhout, T., 2010. Cryptococcus randhawai sp. nov., a novel anamorphic basidiomycetous yeast isolated from tree trunk hollow of Ficus religiosa (peepal tree) from New Delhi, India. Antonnie van Leeuwenhoek 97, 253–259. https://doi.org/10.1007/s10482-009-9406-8. Loˊay, A.A., Dawood, H.D., 2017. Active chitosan/PVA with ascorbic acid and berry quality of ‘Superior seedless’ grapes. Sci. Hortic. 224, 286–292. https://doi.org/10. 1016/j.scienta.2017.06.043. Loˊay, A.A., EI-Khateeb, A.Y., 2018. Impact of chitosan/PVA with salicylic acid, cell wall degrading enzyme activities and berries shattering of ‘Thompson seedless’ grape vines during shelf life. Sci. Hortic. 238, 281–287. https://doi.org/10.1016/j.scienta. 2018.04.061. Loˊay, A.A., EL-Boray, M.S., 2018. Improving fruit cluster quality attributes of ‘Flame seedless’ grapes using preharvest application of ascorbic and salicylic acid. Sci. Hortic. 233, 339–348. https://doi.org/10.1016/j.scienta.2018.02.010. Lyons, J.M., 1973. Chilling injury in plants. Ann. Rev. Plant Physiol. 24 (1), 445–466. https://doi.org/10.1146/annurev.pp.24.060173.002305. Malbaša, R.V., Lončar, E.S., Vitas, J.S., Čanadanović-Brunet, J.M., 2011. Influence of starter cultures on the antioxidant activity of kombucha beverage. Food Chem. 127,
139
Contents lists available at ScienceDirect
Scientia Horticulturae journal homepage: www.elsevier.com/locate/scihorti
The biocontrol of postharvest decay of table grape by the application of kombucha during cold storage
T
⁎
Xian Zhoua, Junping Tana, Yuanyuan Goua, Yongling Liaoa, Feng Xua, , Gang Lia, Jie Caoa, ⁎ Jinglei Yaoa, Jiabao Yea, Ning Tangb, Zexiong Chenb, a b
College of Horticulture and Gardening, Yangtze University, Jingzhou, 434025, Hubei, China Research Institute for Special Plants, Chongqing University of Arts and Sciences, ChongQing, 402160, China
A R T I C LE I N FO
A B S T R A C T
Keywords: Table grape Kombucha Fruit quality Decay Cold storage Antioxidant enzyme
Grapes are susceptible to fungal infection and decay after harvest. The objective of this study was to investigate the effects of kombucha on postharvest fresh-keeping in table grape (Vitis vinifera cv. Fujiminori). Here, we studied the effects of kombucha on the fruit quality and antioxidant system of grape at 4 °C storage. The fruits of grape were dipped into water or kombucha for 15 min and then stored at 4 °C. The physical parameters of fruits, such as the good fruit rate, fruit hardness, contents of soluble solid, ascorbic acid (Vit C) and malodialdehyde (MDA), and activities of the antioxidant enzymes were measured during storage. The application of kombucha reduced deterioration of table fruit during cold storage. The kombucha treatment also delayed the decrease in fruit hardness, soluble solid and Vit C contents, and inhibited the MDA accumulation in grape during storage. Furthermore, fruit treated with kombucha showed significantly higher activities of polyphenol oxidase, peroxidase, catalase and superoxide dismutase with a significantly lower MDA accumulation at the late stage of storage compared the control. Our findings suggested that kombucha application was useful in inhibiting postharvest decay of table grape fruit and appeared to have potential for commercial application to store table grape at cold storage.
1. Introduction Grape is an important cash crop that is widely distributed all over the world. Grape berries are characterized by their bright color, juicy taste, and high nutrient and carbohydrate contents. They are also rich in vitamins, anthocyanins, carotenoids, and several antioxidants. These substances can effectively remove free radicals from the body and delay senility (Zhou and Raffoul, 2012; Ye et al., 2016). In addition, grapes contain a variety of bioactive ingredients that can reduce the risks of cardiovascular disease, diabetes, and cancer in populations that consume grapes. Grape berries are easily dehydrated during storage and are susceptible to rot caused by fungal infection. Dehydration and rotting affect the quality of grape berries (de Sousa et al., 2013). Therefore, in this work, we aimed to solve the problems associated with the storage and preservation of grape berries. Grape preservatives studied at home and abroad are mainly classified as chemical, physical, or biological preservatives. (SO3)2−, chitosan /PVA with salicylic acid, and polyamines are applied as chemical preservatives (Champa et al., 2015; Xue and Yi, 2017; Loˊay and ELBoray, 2018). Ultraviolet light type C radiation and CO2 treatment are ⁎
examples of physical preservatives (Maurer et al., 2017; Cefola et al., 2018). Aureobasidium pullulans (Mari et al., 2012), Cryptococcus laurenti (Meng et al., 2010), and Hanseniaspora uvarum (Qin et al., 2015) are used as biological preservatives. (SO3)2− is the most commonly used chemical preservative. It increases L-phenylalanin ammonia-lyase (PAL) and polyphenol oxidase (PPO) activities by releasing SO2. It enhances grape disease resistance and prolongs storage life by activating defense responses related to secondary metabolism and PR proteins (Xue and Yi, 2017). However, low doses of (SO3)2− have poor preservative effects because they release insufficient amounts of SO2, and excessively high doses of (SO3)2− will bleach grape berries. The spots caused by (SO3)2− bleaching affect the appearance of grapes and are harmful to the health of consumers (Smilanick et al., 1990). CO2 treatment is currently the most commonly used physical preservative method. Treatment with 10% CO2 can maintain the sensory quality and nutritional quality of grapes and delay the senescence of grape berries. Extremely high CO2 concentrations, however, will intensify anaerobic respiration; produce harmful substances, such as ethanol and acetaldehyde; promote the rapid propagation of some anaerobic microorganisms; and cause fruit dehydration, alcoholization, and blackcore
Corresponding authors. E-mail addresses: [email protected] (F. Xu), [email protected] (Z. Chen).
https://doi.org/10.1016/j.scienta.2019.04.025 Received 31 December 2018; Received in revised form 20 March 2019; Accepted 11 April 2019 0304-4238/ © 2019 Elsevier B.V. All rights reserved.
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
grape fruit every storage period over initial weight of grape fruit before storage, expressed as a percentage. Fruit hardness was determined by using the fruit hardness tester referring method of Segade et al (2013). The assay of soluble solid content were carried out using a refractiometer (ATAGO China Guangzhou Co., ltd, Japan). Three-hundred μL juice of broken grape was placed on prism of the instrument to reading (Mariani et al., 2014). The content of Vit C was measured using the methods described by Rekha et al. (2012).
(Cefola et al., 2018). Biological preservatives are easy to cultivate, environmentally friendly, and nontoxic. They exert their preservative effects by competing with harmful microorganisms for space and nutrients (Droby et al., 2009). For example, the binding between C. laurentii and chitosan in grape berries drastically increases PAL and PPO activities, improves disease resistance, and reduces decay rate (Meng et al., 2010). The cell suspensions of Candida oleophila can induce the accumulation of chitinase, β-1, 3-endoglucanase, and phytoalexins and improve the control of Penicillium digitatum infections in grapefruit (Droby et al., 2002). A. pullulans, Metschnikowia sp. and Pseudozyma fusiformata exert a strong inhibitory effect on the brown rot of peach (Zhang et al., 2010). Kombucha is produced by fermenting tea using a symbiotic culture of bacteria and yeast (Dufresne and Farnworth, 2000). Kombucha is a slightly sweet and slightly acidic drink. It can prevent various cancers and cardiovascular and cerebrovascular diseases, promote liver function, and stimulate the immune system (Malbaša et al., 2011). It is produced through the fermentation of tea sugar water by microzymes, acetic acid bacteria, and lactic acid bacteria (Chen and Liu, 2000). Kombucha has an inhibitory effect on Escherichia coli, Bacillus subtilis, and Staphylococcus aureus (Sreeramulu et al., 2000). Given these characteristics, it can be speculated that kombucha is a potential natural pollution-free food preservative that can be used as an alternative to chemical preservatives in fruit. However, the application of kombucha in fruit and vegetable preservation has not been studied. In this work, we investigated the effect of treatment with kombucha on the postharvest decay, fruit quality and antioxidant enzyme activities of table grape during storage at 4 °C. Our study should be helpful for further development of commercial and non-chemical postharvest technology for quality maintenance and shelf life extension of table grape.
2.3. Assay of malondialdehyde (MDA) content and antioxidant enzyme activity Malondialdehyde (MDA) content was measured by thiobarbituric acid method (Heath and Packer, 1968). In the method, the reaction produces a colored trimethyl compound with different absorbance values at different wavelengths of 450 nm, 532 nm, and 600 nm. MDA content was calculated according the following formula: C (μmol/ L) = 6.45 (A532-A600) - 0.56 A450. Superoxide dismutase (SOD) activity was measured by the method of nitrotetrazolium blue chloride (NBT) described by (Cao et al., 2011). One unit of SOD activity was defined as inhibition of 50% NBT photoreduction. Peroxidase (POD) activity was assayed using guaiacol oxidation method, one unit of peroxidase activity was defined as the amount of enzyme which change the absorbance value of 0.01 per minute (Ciou et al., 2011). Catalase (CAT) activity was assayed by ultraviolet spectrophotometry (Aebi, 1984). Polyphenol oxidase (PPO) activity was assayed using the catechol method, one unit was defined as changing 0.01 for 1 ml per minute (Queiroz et al., 2011). 2.4. Statistical analysis
2. Materials and methods
All data presented were means of 6 replicates with standard errors (SD). Data were subjected to analysis of variance, and means were compared using least significance difference (LSD) test using SPSS 10.0 for Windows (SPSS Inc., IL, USA,). Difference at p < 0.05 indicates significant.
2.1. Preparation of kombucha, fruit materials and treatments The kombucha solution were preserved in our laboratory. The kombucha was prepared by the following method. Mixture about 6 l was boiled for 10 min, of which ratio was boiled water 0.5 l, sucrose 50 g (g) and black tea 5 g. Then, the mixture was dispensed into 6 glass jars (1 l) by funnel filtered to remove tea grounds. Finally, the kombucha solution inoculated together into the above liquid. The liquid was fermented for 2 weeks under 28 °C. Kombucha was prepared successfully and the filtrate was the kombucha fermentation broth used to treat table grape fruits. The table grape (Vitis vinifera cv. Fujiminori) were harvested on 5th August in Yangtze University deciduous fruit base, Jingzhou, China (around N30.35, E112.14). Harvested grape clusters were dipped in water to clean the surfaces and then selected based on uniformity of size, color, and disease-free. The selected fruits were divided into two groups. One group was immersed in distilled water for 15 min as control and the other group was dipped into kombucha fermentation broth for 15 min as treatment. The control and treated grape fruits were airdried, then packed into plastic polyethylene bags, and then stored for 33 days at 4 °C storage and 70–80% relative humidity. Grape fruit was sampled at the 0 st, the 3rd, the 6th, the 9th, the 12th, the 15th, the 18th, the 21th, the 24th, the 27th, the 30th, the 33th day after treatments, respectively. Each treatment consisted of six replication with ten table grape berries per replication. The assays were performed at least three times.
3. Results 3.1. Effect of kombucha on good fruit rate, water loss rate and fruit firmness in table grape The rate of good fruit is defined as the percentage of fruits without mechanical injury, insect damage, and disease spots as identified through naked-eye observation. As shown in Fig. 1A, the rate of good fruits decreased with the prolongation of storage time. The rate of good fruits treated with kombucha was significantly higher than that in control during storage. The rates of good fruits in the treatment and control groups were 42.5% and 24.5%, respectively, after 33 d of storage. This result indicates that kombucha exerted a preservative effect on the treated grapes. As shown in Fig. 1B, the weight loss rate of grapes increased with the extension of storage time. The greatest difference between the weight losses of the control and treatment groups was observed after 33 d of storage. The treatment reduced the mass loss of the fruits in 50% compared with the control. The hardness of grape berries in the treatment group and the control group decreased with storage time (Fig. 1C). The hardness of grape berries treated with kombucha was consistently higher than that of non-kombucha-treated grape berries. After 33 d of storage, the hardness of grape berries in the treatment group (1.6 N) was 3.4 times of that of grape berries in the control group (0.48 N).
2.2. Measurement of good fruit rate, weight loss, fruit hardness, soluble solid content (SSC), ascorbic acid (Vit C)
3.2. Effects of kombucha on soluble solid and Vit C in table grapes
Good fruit rate was evaluated by number of good grape fruit every storage period compared total number of grape fruit before storage, expressed as a percentage. Weight loss was calculated by weight change
The soluble solid contents of the control and treatment fruit first 135
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
control group first rapidly increased and then slowly decreased. In particular, the soluble solid content of the treatment group was significantly higher than that of the control group during the later stages of storage. As shown in Fig. 3B, the Vit C contents of the control and treatment groups decreased rapidly during the early stages of storage and slowly decreased during the later stages of storage. On 33 d of storage, the Vit C content of the treatment group was 5.43 mg/100 g, which was significantly higher than that of the control group (4.34 mg/ 100 g). 3.3. Effects of kombucha on the content of MDA in table grapes MDA is used as an indicator of the degree of lipid peroxidation in the cell membranes of fruits. The MDA contents of the treatment and control groups increased. The MDA content of the treatment group was consistently significantly lower than that of the control group during storage (Fig. 4). The MDA content of the control increased slowly from 3rd to 21th and the treatment group increased slowly from 3rd to 24th. However, MDA content of the control and treatment group rased rapidly. MDA content of the treatment was lower than the control until 33rd. 3.4. Effects of kombucha on antioxidant enzyme activities in table grapes As shown in Fig. 5A, PPO activities in the control and treatment groups increased and did not significantly differ during the early stages of storage (0–15 d). The increase in PPO activity after 15 d of storage was more rapid in the control than that in the treatment. PPO activity in treatment group was significantly lower than that in the control group from 15 to 33 d of storage (p < 0.05). POD activities in the treatment and control groups increased during storage (Fig. 5B). After 24 d of storage, POD activity in the kombucha treatment was always higher than that in the control group. Catalase (CAT) activities in the treatment and control groups first decreased and then increased (Fig. 5C) and reached the lowest values of 3.65 and 2.45U/g−1min – 1, respectively, on 18 d of storage. CAT activity in the treatment group was higher than that in the control group throughout the entirety of the storage period. As shown in Fig. 5D, SOD activity in the treatment and control groups first increased and then decreased with the prolongation of storage time and reached the maximum values of 57.43 and 50.13 U/ g, respectively, on 24 d of storage. During the whole storage period, SOD activity in the treatment group was significantly higher than that in the control group (p < 0.05). The above results show that treatment with kombucha can prolong the freshness of grapes during storage by attenuating active oxygen production. Kombucha reduces active oxygen production by increasing the activity of antioxidant enzymes. 4. Discussion Grape berries are non-respiratory climacteric fruits with high water content. They undergo a series of postharvest physiological and biochemical reactions that increase their susceptibility to pathogen-induced processes, such as decay, drying, and wilting (de Sousa et al., 2013). Changes in respiration and transpiration rates mainly cause the postharvest water loss of grape berries (Min et al., 2001). Loˊay and Dawood (2017) found that chitosan can reduce the rate of water and weight loss of grape berries by forming films that inhibit respiration on grape skins. In this study, we found that kombucha can reduce the water loss rate of grapes, similar to the effect of chitosan on grape. Kombucha promotes water retention and decreases water loss rate by forming a film on grape skins (Fig. 2). This film ultimately prolongs the shelf life of grapes by inhibiting water evaporation, reducing respiratory rate, and preventing infection by pathogenic bacteria. The main components of the fruit cytoderm include insoluble pectin, cellulose, and hemicellulose. These substances are closely related to the hardness of fruits and are degraded by pectinase and
Fig. 1. Effects of kombucha on good fruit rate (A), weight loss (B) and fruit hardness(C) of grape. The data are displayed with mean ± SD (bars) of 6 replication.
increased and then decreased. The soluble solid contents of grape berries in the control and treatment groups peaked after 9 d and 21 d of storage, respectively (Fig. 3A). During 3–12 d of storage, the soluble solid content of the control group was higher than that of the treatment group. The greatest difference between the soluble solid content of the two groups was observed on 9 d of storage. The soluble solid content of the treatment group was higher than that of the control group beginning on 15 d of storage onwards. To summarize, the soluble solid content of the treatment group first slowly increased and then slowly decreased during storage. By contrast, the soluble solid content of the 136
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
Fig. 2. The grape was affected by water (A, C) and kombucha(B, D).
Fig. 4. Effects of kombucha on MDA content in grape fruit. The data are displayed with mean ± SD (bars) of 6 replication.
salicylic acid can prevent fruit hardness from decreasing and prolong fruit storage life by decreasing the activity of cellulase, polygalacturonase, and xylanase and decelerating the degradation of cellulose, hemicellulose, and pectin (Loˊay and EI-Khateeb, 2018). Like chitosan /PVA with salicylic acid, our data revealed that kombucha decelerates fruit softening by inhibiting the activities of degradative enzymes in the cytoderm of grape berries (Champa et al., 2015). The physiological mechanism related to this effect requires further study. Vit C, soluble solids and anthocyanins are important indicators used for evaluating fruit quality (Ye et al., 2017). These components also participate in reactive oxygen scavenging and physiological responses by acting as the cofactors of various enzymes (Fransson and Mani, 2007). Vit C can prevent the browning of fruit by inhibiting the PPOcatalyzed formation of phenols from quinones (Tate et al., 1964). It exerts a strong concentration-dependent inhibitory effect on PPO and POD activities. This study showed that kombucha can effectively inhibit the postharvest Vit C degradation of grapes and promote the accumulation of soluble solids. Taken that sugar accumulation in fruits can increase Vit C content (Massot et al., 2010), it can be concluded that Kombucha treatment may increase the content of soluble solids in the
Fig. 3. Effects of kombucha on content of soluble solid content (SSC) (A) and ascorbic acid (Vit C) (B) in grape fruit. The data are displayed with mean ± SD (bars) of 6 replication.
hemicellulase during fruit maturation. The degradation of pectin and hemicellulose results in pulp tissue softening and decreases fruit hardness (Deng et al., 2013). Postharvest treatment with chitosan/PVA with 137
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
Fig. 5. Effects of kombucha on polyphenol oxidase (PPO) activity (A), peroxidase (POD) activity (B), catalase (CAT) activity (C) and superoxide dismutase (SOD) activity (D) in grape fruit. The data are displayed with mean ± SD (bars) of 6 replication.
that treatment with kombucha can increase POD activity in grapes. Our finding is consistent with that of (Khan et al., 2010) that treatment with Rhodotorula glutinis can maintain peach fruit quality by inducing host POD activity. Therefore, kombucha may improve quality fruit by increasing POD enzyme scavenging or preventing reactive oxygen species production. At the same time, it participates in the synthesis of phenolic compounds, phytoprotective substances, lignin, and other stress-resistant substances in fruits and vegetables. The presence of these components ultimately maintains fruit quality by delaying fruit softening and improving disease resistance. Moreover, POD is related to fruit color, flavor, and nutrient formation (Ferrer et al., 2005; Zhong et al., 2005, 2007). In addition to POD, SOD and CAT are important enzymes in plant resistance physiology. SOD is a natural free radical scavenger in biological organisms. It can catalyze O2− dismutation, which yields H2O2 and O2 as products (Van Camp et al., 1996). CAT alleviates the toxicity of H2O2 to plant tissues by scavenging H2O2 into H2O and O2. Our results showed that the activity of SOD, which scavenges O2−, increased during the early stage of treatment with kombucha. SOD activity gradually declined in the late stage of treatment. This decline may be attributed to the coordination of its own enzyme system. CAT activity, however, slightly decreased at early stage of storage and then subsequently decreased at late stage of storage. This increase may be related to the constant resistance response of grapes. The activities of the antioxidant enzymes (POD, SOD, and CAT) in grapes increased after treatment with kombucha, indicating that kombucha treatment can improve the antioxidant capacity of grape berries and has potential applications as a preservative.
form of soluble sugar during the early stages of storage. In addition, the higher Vit C content of the treatment group than that of the control group may be attributed to the transformation of some soluble solids into Vit C. MDA is an important indicator applied for evaluating the stability of plant membrane systems. Membrane system stability is closely related to plant stress resistance (Lyons, 1973). Its strong reactions with various cellular components severely damage enzymes and membranes and reduce membrane resistance and fluidity. These effects eventually cause the destruction of membrane structure and physiological integrity (Scandalios, 1993). Changes in MDA content reflect the degree of cellular membrane lipid peroxidation (Juan et al., 2011). We demonstrated that MDA content, which reflects the degree of membrane lipid peroxidation in fruits, gradually increased as grape ripening and senescence progressed during storage. Consistent with the findings of a study showing that treatment with Pichia guilliermondii and hot air can reduce membrane lipid peroxidation in peach (Zhao et al., 2019), treatment with kombucha can reduce membrane lipid peroxidation during fruit storage. Thus, our results further indicated that kombucha treatment can prevent the postharvest deterioration of cell membrane structure and attenuate reductions in nutrient content and flavor quality by reducing MDA accumulation. Antioxidant enzymes, such as SOD, POD, and CAT, play important roles in scavenging reactive oxygen species, reducing membrane lipid peroxidation levels, and improving plant stress adaptability (Ye et al., 2016; Yang et al., 2016). POD, an important defensive enzyme in the phenylpropane metabolic pathway, is closely related to the disease resistance of plants. It helps catalyze lignin production and enhances cell structural stability (Mohammadi and Kazemi, 2002). It is also a key enzyme in fruit refrigeration and browning (Richard-Forget and Gauillard, 1997). Browning can reduce nutritional quality and consumer acceptance by changing fruit traits (Ciou et al., 2011). We found
5. Conclusions In conclusion, our results provide evidence of the ability of kombucha to reduce of postharvest decay and maintain the fruit quality in 138
Scientia Horticulturae 253 (2019) 134–139
X. Zhou, et al.
table grape during cold storage. Kombucha application prevent weight loss and fruit softening, while improving soluble solid and Vit C contents in table grape during cold storage. Kombucha increase antioxidant enzyme (POD, SOD, and CAT) activity and thus delay cellular membrane lipid peroxidation. Our findings suggested that the kombucha treatment is a safe and commercial postharvest mean for maintaining quality and prolonging storage life of harvested table grapes.
1727–1731. https://doi.org/10.1016/j.foodchem.2011.02.048. Mari, M., Martini, C., Spadoni, A., Rouissi, W., Bertolini, P., 2012. Biocontrol of apple postharvest decay of Aureobsidium pullulans. Postharvest Biol. Tec. 73, 56–62. https://doi.org/10.1016/j.postharvbio.2012.05.014. Mariani, N.C.T., da Costa, R.C., de Lima, K.M.G., Nardini, V., Júnior, L.C.C., de Almeida Teixeira, G.H., 2014. Predicting soluble solid content in intact jaboticaba [Myrciaria jaboticaba (Vell.) O. Berg] fruit using near-infrared spectroscopy and chemometrics. Food Chem. 159, 458–462. https://doi.org/10.1016/j.foodchem.2014.03.066. Massot, C., Génard, M., Stevens, R., Gautier, H., 2010. Fluctuations in sugar content are not determinant in explaining variations in vitamin C in tomato fruit. Plant Physiol. Biochem. 48, 751–757. https://doi.org/10.1016/j.plaphy.2010.06.001. Maurer, L.H., Bersch, A.M., Santos, R.O., Trindade, S.C., Costa, E.L., Peres, M.M., 2017. Postharvest UV-C irradiation stimulates the non-enzymatic and enzymatic antioxidant system of ‘Isabel’ hybrid grapes (Vitis labrusca×Vitis vinifera L.). Food Res. Int. 102, 738–747. https://doi.org/10.1016/j.foodres.2017.09.053. Meng, X.H., Qin, G.Z., Tian, S.P., 2010. Influences of preharvest spraying Cryptococcus laurentii, combined with postharvest chitosan coating on postharvest diseases and quality of table grapes in storage. LWT-Food Sci. Technol. 43, 596–601. https://doi. org/10.1016/j.lwt.2009.10.007. Min, Z., Chunli, L., Yanjun, H., Qian, T., Haiou, W., 2001. Preservation of fresh grapes at ice-temperature-high-humidity. Int. Agrophys. 15, 139–143. Mohammadi, M., Kazemi, H., 2002. Changes in peroxidase and polyphenol oxidase activities in susceptible and resistant wheat heads inoculated with Fusarium graminearum and induced resistance. Plant Sci. 162, 491–498. https://doi.org/10.1016/ S0168-9452(01)00538-6. Qin, X., Xiao, H., Xue, C., Yu, Z., Yang, R., Cai, Z., Si, L., 2015. Biocontrol of gray mold in grapes with the yeast Hanseniaspora uvarum, alone and in combination with salicylic acid or sodium bicarbonate. Postharvest Biol. Tec. 100, 160–167. https://doi.org/10. 1016/j.postharvbio.2014.09.010. Queiroz, C., da Silva, A.J.R., Lopes, M.L.M., Fialho, E., Valente-Mesquita, V.L., 2011. Polyphenol oxidase activity, phenolic acid composition and browning in cashew apple (Anacardium occidentale, L.) after processing. Food Chem. 125, 128–132. https://doi.org/10.1016/j.foodchem.2010.08.048. Rekha, C., Poornima, G., Manasa, M., Abhipsa, V., Devi, J.P., Kumar, V.H.T., Kekuda, T.R.P., 2012. Ascorbic acid, total phenol content and antioxidant activity of fresh juices of four ripe and unripe citrus fruits. Chem. Sci. Trans. 1, 303–310. https://doi. org/10.7598/cst/2012.182. Richard-Forget, F.C., Gauillard, F.A., 1997. Oxidation of chlorogenic acid, catechins, and 4-methylcatechol in model solutions by combinations of pear (Pyrus communis cv. Williams) polyphenol oxidase and peroxidase: a possible involvement of peroxidase in enzymatic browning. J. Agric. Food Chem. 45, 2472–2476. https://doi.org/10.1021/ jf970042f. Scandalios, J.G., 1993. Oxygen stress and superoxide dismutases. Plant Physiol. 101 (1), 7–12. https://doi.org/10.1104/pp.101.1.7. Segade, S.R., Giacosa, S., Torchio, F., Palma, L.D., Novello, V., Gerbi, V., Rolle, L., 2013. Impact of different advanced ripening stages on berry texture properties of ‘Red Globe’ and ‘Crimson Seedless’ table grape cultivars (Vitis vinifera, L.). Sci. Hortic. 160, 313–319. https://doi.org/10.1016/j.scienta.2013.06.017. Smilanick, J.L., Harvey, J.M., Hartsell, P.L., Henson, D.J., Harris, C.M., Fouse, D.C., Assemi, M., 1990. Influence of sulfur dioxide fumigant dose on residues and control of postharvest decay of grapes. Plant Dis. 74, 418–421. https://doi.org/10.1094/PD74-0418. Sreeramulu, G., Zhu, Y., Knol, W., 2000. Kombucha fermentation and its antimicrobial activity. J. Agric. Food Chem. 48, 2589–2594. https://doi.org/10.1021/jf991333m. Tate, J.N., Luh, B.S., York, G.K., 1964. Polyphenol oxidase in Barlett pears. J. Food Sci. 29, 829–836. https://doi.org/10.1111/j.1365-2621.1964.tb00456.x. Van Camp, W., Capiau, K., Van Montagu, M., Inze, D., Slooten, L., 1996. Enhancement of oxidative stress tolerance in transgenic tobacco plants overproducing Fe-superoxide dismutase in chloroplasts. Plant Physiol. 112, 1703–1714. https://doi.org/10.1104/ pp.112.4.1703. Xue, M., Yi, H., 2017. Induction of disease resistance providing new insight into sulfur dioxide preservation in Vitis vinifera L. Sci. Hortic. 225, 567–573. https://doi.org/10. 1016/j.scienta.2017.07.055. Yang, F., Xu, F., Wang, X.H., Liao, Y.L., Chen, Q.W., Meng, X.X., 2016. Characterization and functional analysis of a MADS-box transcription factor gene (GbMADS9) from Ginkgo biloba. Sci. Hortic. 212, 104–114. https://doi.org/10.1016/j.scienta.2016.09. 042. Ye, J.B., Chen, Q.W., Tao, T.T., Wang, G., Xu, F., 2016. Promotive effects of 5-aminolevulinic acid on growth, photosynthetic gas exchange, chlorophyll, and antioxidative enzymes under salinity stress in Prunnus persica (L.) Batseh seedling. Emir. J. Food Agric. 786–795. https://doi.org/10.9755/ejfa.2016-06-647. Ye, J.B., Xu, F., Wang, G.Y., Chen, Q.W., Tao, T.T., Song, Q.L., 2017. Molecular cloning and characterization of an anthocyanidin synthase gene in Prunus persica (L.) batsch. Not. Bot. Hortic. Agrobo. 45 (1), 28–35. https://doi.org/10.15835/nbha45110546. Zhang, D., Spadaro, D., Garibaldi, A., Gullino, M.L., 2010. Selection and evaluation of new antagonists for their efficacy against postharvest brown rot of peaches. Postharvest Biol. Techcnol. 55, 174–181. https://doi.org/10.1016/j.postharvbio. 2009.09.007. Zhao, Y., Li, Y., Yin, J., 2019. Effects of hot air treatment in combination with Pichia guilliermondii on postharvest preservation of peach fruit. J. Sci. Food Ag. 99 (2), 647–655. https://doi.org/10.1002/jsfa.9229. Zhong, K., Hu, X., Zhao, G., Chen, F., Liao, X., 2005. Inactivation and conformational change of horseradish peroxidase induced by pulsed electric field. Food Chem. 92, 473–479. https://doi.org/10.1016/j.foodchem.2004.08.010. Zhong, K., Wu, J., Wang, Z., Chen, F., Liao, X., Hu, X., Zhang, Z., 2007. Inactivation kinetics and secondary structural change of PEF-treated POD and PPO. Food Chem. 100 (1), 15–123. https://doi.org/10.1016/j.foodchem.2005.09.035. Zhou, K., Raffoul, J.J., 2012. Potential anticancer properties of grape antioxidants. J. Oncol. 2012, 803294. https://doi.org/10.1155/2012/803294.
Acknowledgement This study was supported by the Science and Technology Development Project of Jingzhou City (2011CB36). References Aebi, H., 1984. Catalase in vitro. Methods Enzymol. 105, 121–126. https://doi.org/10. 1016/S0076-6879(84)05016-3. Cao, S., Hu, Z., Zheng, Y., Yang, Z., Lu, B., 2011. Effect of BTH on antioxidant enzymes, radical-scavenging activity and decay in strawberry fruit. Food Chem. 125, 145–149. https://doi.org/10.1016/j.foodchem.2010.08.051. Cefola, M., Damascelli, A., Lippolis, V., Cervellieri, S., Linsalata, V., Logrieco, A.F., Pace, B., 2018. Relationships among volatile metabolites, quality and sensory parameters of ‘Italia’ table grapes assessed during cold storage in low or high CO2 modified atmospheres. Postharvest Biol. Technol. 142, 124–134. https://doi.org/10.1016/j. postharvbio.2017.09.002. Champa, W.A.H., Gill, M.I.S., Mahajan, B.V.C., Bedi, S., 2015. Exogenous treatment of spermine to maintain quality and extend postharvest life of table grapes (Vitis vinifera L.) cv. Flame Seedless under low temperature storage. LWT-Food Sci. Technol. 60, 412–419. https://doi.org/10.1016/j.lwt.2014.08.044. Chen, C., Liu, B.Y., 2000. Changes in major components of tea fungus metabolites during prolonged fermentation. J. Appl. Microbiol. 89, 834–839. https://doi.org/10.1046/j. 1365-2672.2000.01188. Ciou, J.Y., Lin, H.H., Chiang, P.Y., Wang, C.C., Charles, A.L., 2011. The role of polyphenol oxidase and peroxidase in the browning of water caltrop pericarp during heat treatment. Food Chem. 127, 523–527. https://doi.org/10.1016/j.foodchem.2011.01. 034. de Sousa, L.L., de Andrade, S.C.A., Athayde, A.J.A.A., de Oliveira, C.E.V., de Sales, C.V., Madruga, M.S., de Souza, E.L., 2013. Efficacy of Origanum vulgare L. and Rosmarinus officinalis L. essential oils in combination to control postharvest pathogenic Aspergilli and autochthonous mycoflora in Vitis labrusca L. (table grapes). Int. J. Food Microbiol. 165, 312–318. https://doi.org/10.1016/j.ijfoodmicro.2013.06.001. Deng, J., Liu, H.M., Zhang, N.X., Yan, Y., Li, X.Z., 2013. Effects of postharvest calcium and heat treatment on cell wall material metabolism during grapefruit storage. Nor. Hortic 000123-129. Droby, S., Vinokur, V., Weiss, B., Cohen, L., Daus, A., Goldschmidt, E.E., Porat, R., 2002. Induction of resistance to Penicillium digitatum in grapefruit by the yeast biocontrol agent Candida oleophila. Phytopathology 92, 393–399. https://doi.org/10.1094/ phyto.2002.92.4.393. Droby, S., Wisniewski, M., Macarisin, D., Wilson, C., 2009. Twenty years of postharvest biocontrol research: is it time for a new paradigm. Postharvest Biol. Technol. 52, 137–145. https://doi.org/10.1016/j.postharvbio.2008.11.009. Dufresne, C., Farnworth, E., 2000. Tea, kombucha, and health: a review. Food Res. Int. 33, 409–421. https://doi.org/10.1016/S0963-9969(00)00067-3. Ferrer, A., Remón, S., Negueruela, A.I., Oria, R., 2005. Changes during the ripening of the very late season Spanish peach cultivar Calanda: feasibility of using CIELAB coordinates as maturity indices. Sci. Hortic. 105, 435–446. https://doi.org/10.1016/j. scienta.2005.02.002. Fransson, L.A., Mani, K., 2007. Novel aspects of vitamin C: how important is glypican-1 recycling. Trends Mol. Med. 13, 143–149. https://doi.org/10.1016/j.molmed.2007. 02.005. Heath, R.L., Packer, L., 1968. Photoperoxidation in isolated chloroplasts: I. Kinetics and stoichiometry of fatty acid peroxidation. Arch. Biochem. Biophys. 125, 189–198. https://doi.org/10.1016/0003-9861(68)90654-1. Juan, K.A.N., Wang, H.M., Jin, C.H., 2011. Changes of reactive oxygen species and related enzymes in mitochondrial respiration during storage of harvested peach fruits. Agric. Sci. China 10, 149–158. https://doi.org/10.1016/S1671-2927(11)60317-9. Khan, Z.U., Ahmad, S., Hagen, F., Fell, J.W., Kowshik, T., Chandy, R., Boekhout, T., 2010. Cryptococcus randhawai sp. nov., a novel anamorphic basidiomycetous yeast isolated from tree trunk hollow of Ficus religiosa (peepal tree) from New Delhi, India. Antonnie van Leeuwenhoek 97, 253–259. https://doi.org/10.1007/s10482-009-9406-8. Loˊay, A.A., Dawood, H.D., 2017. Active chitosan/PVA with ascorbic acid and berry quality of ‘Superior seedless’ grapes. Sci. Hortic. 224, 286–292. https://doi.org/10. 1016/j.scienta.2017.06.043. Loˊay, A.A., EI-Khateeb, A.Y., 2018. Impact of chitosan/PVA with salicylic acid, cell wall degrading enzyme activities and berries shattering of ‘Thompson seedless’ grape vines during shelf life. Sci. Hortic. 238, 281–287. https://doi.org/10.1016/j.scienta. 2018.04.061. Loˊay, A.A., EL-Boray, M.S., 2018. Improving fruit cluster quality attributes of ‘Flame seedless’ grapes using preharvest application of ascorbic and salicylic acid. Sci. Hortic. 233, 339–348. https://doi.org/10.1016/j.scienta.2018.02.010. Lyons, J.M., 1973. Chilling injury in plants. Ann. Rev. Plant Physiol. 24 (1), 445–466. https://doi.org/10.1146/annurev.pp.24.060173.002305. Malbaša, R.V., Lončar, E.S., Vitas, J.S., Čanadanović-Brunet, J.M., 2011. Influence of starter cultures on the antioxidant activity of kombucha beverage. Food Chem. 127,
139