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Data on parametric influence of microwave-assisted extraction on the recovery yield, total phenolic content and antioxidant activity of Phaleria macrocarpa fruit peel extract
Chemical Data Collections 24 (2019) 100277
Contents lists available at ScienceDirect
Chemical Data Collections journal homepage: www.elsevier.com/locate/cdc
Data Article
Data on parametric influence of microwave-assisted extraction on the recovery yield, total phenolic content and antioxidant activity of Phaleria macrocarpa fruit peel extract Oluwaseun Ruth Alara a, Siti Kholijah Abdul Mudalip a,b,∗, Nour Hamid Abdurahman a,b, Mohammed Saeed Mahmoud a, Emmanuel Ogo-Oluwa Obanijesu c a
Faculty of Chemical and Natural Resources Engineering, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300, Gambang, Pahang, Malaysia Centre of Excellence for Advanced Research in Fluid Flow, Universiti Malaysia Pahang, 26300 Gambang, Pahang, Malaysia c School of Education, Edith Cowan University, Joondalup Campus, Perth, Australia b
a r t i c l e
i n f o
a b s t r a c t
Article history: Received 6 February 2019 Revised 10 September 2019 Accepted 10 September 2019 Available online 11 September 2019 Keywords: Microwave-assisted extraction Phaleria macrocarpa Antioxidant Total phenolic content Yield
Phaleria macrocarpa, commonly known as Mahkota dewa is a well-known medicinal plant native to Malaysia and Indonesia. P. macrocarpa has been used as traditional medicine for the treatment of many diseases for a long time. In this study, P. macrocarpa peels’ bioactive compounds were extracted using microwave-assisted extraction method. The effects of different process parameters such as irradiation time (0.5, 1, 3, 5, and 10 min), microwave temperatures (60, 70, 80, 90, and 100 °C) and microwave power (20 0, 30 0, 40 0, 50 0, and 600 W) on the extraction yield were investigated. Moreover, the antioxidant activity and total phenolic (TPC) content of the extract were estimated. The results reflected that the extraction yields, antioxidant activity and total phenolic content increased with increasing levels of process parameters to certain conditions where highest yields were attained. However, the best conditions of processing parameters that resulted to the highest amount of yield (61.25%) were 1 min, 80 °C and 300 W. The highest amount of antioxidant activity and TPC yield were 61.15±0.93% and 102.60±1.17 mg GAE/g d.w, respectively. These illustrated that P. macrocarpa peels can serve as a good source of antioxidant. © 2019 Elsevier B.V. All rights reserved.
Specification Table
Subject area: Data category: Data acquisition: Format: Data type: Procedure:
∗
Natural product research Microwave-assisted extraction parameters study, Antioxidant Spectrophotometric analysis Figures Analysed The influences of MAE parameters on the recovery of total phenolic content and antioxidant was studied.
Corresponding author. E-mail address: [email protected] (S.K.A. Mudalip).
https://doi.org/10.1016/j.cdc.2019.100277 2405-8300/© 2019 Elsevier B.V. All rights reserved.
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O.R. Alara, S.K.A. Mudalip and N.H. Abdurahman et al. / Chemical Data Collections 24 (2019) 100277
1. Rationale According to the World Health Organization (WHO), about 80% of the world’s population uses herbal products either as food supplements or as alternative medicine [1]. Mukhtar et al. reported that about 25% of the commonly used medicines contain compounds isolated from plants [2]. In Malaysia, the vast rainforests are blessed with various types of plants with medicinal value. This had therefore found a special place in the treatment of many life-threatening diseases. Chua et al. reported that over 12,0 0 0 of both higher and lower species of plants are available in Peninsular Malaysia with about 16% used for medicinal purposes [3]. There is still an incredible number of unexplored functional plants that can be used in medicine. The consumption of plant foods, particularly fruits, vegetables and cereal grains is therefore encouraged because they render beneficial health effects. An example of this plants is Mahkota Dewa (Phaleria macrocarpa) which is mainly found in the Southeast Asia region, it is commonly referred to as God’s crown [4]. It is important medicinal thick and evergreen plant usually grown in the tropical region. P. macrocarpa trees have the height ranging from 1 to 18 m and leaf length and width ranging from 7 to 10 cm and 3 to 5 cm, respectively. Its fruits are usually grown on trucks and branches and changes from green to red when ripe [5]. This plant has been used in the treatment of several diseases such as Diabetes mellitus, cancer, hemorrhoids, and impotence. This is due to its anti-oxidation, antihistamine and antitumor effects [6]. P. macrocarpa is being used in Indonesia as one of the major ingredients in some brands of tea and healthy drink. Different bioactive compounds such as Mahkoside A, luteolin, tangeritin, quercetin, kaempferol, myricetin, isorhamnetin, pachypodol, hesperetin, naringenin, eriodictyol, catechins and epicatechins, and among others had been previously isolated from Mahkota Dewa [7]. Moreover, recent studies from China, Japan, Malaysia, and Indonesia showed that there are several compounds that were isolated from the fruit extracts of P. macrocarpa. These include dodecanoic acid, palmitic acid, ethyl stearate, sucrose, vasorelaxant icariside C3, and mangiferin [8–11]. One study reported that P. macrocarpa has shown the potential effect of improving male fertility [12]. With the capability of P. macrocarpa in healing and traditionally curing certain diseases, it shows that this plant could be a new natural source for antioxidants molecules. Due to the medicinal value of P. macrocarpa, its extracts have been applied in many areas of food and drug, part of which are in the production of herbal tea, cosmetics, food, and medicine. According to Alara et al., the investigations on medicinal plants are recently achieving more interest due to their potential antioxidant activity and total phenolic contents [13]. These compounds have several biological properties which include anti-inflammation, antioxidant, antimalarial, anti-diabetic, anti-fungi, antimicrobial, and many other benefits. Phenolic compounds are responsible for the amazing taste, flavor, and antioxidant properties found in the leaves and fruits of many medicinal plants [14]. Several secondary metabolites such as phenolic acid and phenolic hydroxyl are known to be active compounds with natural antioxidant properties that are capable of scavenging free superoxide radicals, anti-aging and reducing the risk of cancer. Several extraction methods (conventional and non-conventional) are being used in the extraction of bioactive compounds from plant matrix. Conventional techniques such as maceration, Soxhlet extraction, and solvent extraction are traditionally applied for extraction of plant-based bioactive compounds. Researchers have also studied the efficiency of unconventional methods including ultrasound-assisted extraction and microwave-assisted extraction. Among the non-unconventional methods is microwave-assisted extraction, which has been a novel method that drew the attention of researchers recently because of its shortened extraction time, higher quality of yield and reduced solvent consumption [15,16]. Therefore, this study focused on the use of microwave-assisted extraction technique in the extraction of bioactive compounds from P. macrocarpa fruit peels. 2. Procedure 2.1. Plant materials, chemicals and reagents Dried P. macrocarpa fruit peels were purchased from Ethno Resources Sdn Bhd, Selangor. The sample was ground into a smaller size (0.1 mm) using a Grindomix grinder (GM-200 model, Germany). Analytical grade methanol (99 wt%), gallic acid, Folin-Ciocalteu phenol reagent, 2,2-diphenyl-picrylhydrazyl (DPPH), and sodium carbonate anhydrous were purchased from Merck Sdn Bhd, Selangor. All the reagents were used without further purification but some of the chemical dilutions were conducted according to the experimental protocol. 2.2. Microwave-assisted extraction The extraction process was conducted using an easy control ETHOS-microwave extractor (ATC-300, North America). The microwave system is made up of a programmable auxiliary input system which was used to monitor and set the parameters of extraction. This was equipped with a temperature control optical fiber with a maximum output power of 10 0 0 W at 1 atm. The cooling system has the inlet and outlet port to maintain a boiling temperature balance and microwave power level. Briefly, 6 g of a blended sample of P. macrocarpa fruit peels was extracted using a distilled water in accordance with the OFAT design at a feed-to-solvent ratio of 60 g/L. The mixture was then unloaded from the microwave cavity, the extract was filtered and concentrated to dryness using a rotary evaporator (Buchi-R-200, Germany). The percentage of extraction yield was determined, and the extract was stored at 4ºC until further analysis.
O.R. Alara, S.K.A. Mudalip and N.H. Abdurahman et al. / Chemical Data Collections 24 (2019) 100277
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Fig. 1. Changes in extraction yields as influenced by irradiation time. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
2.3. Determination of phenolic content The total phenolic contents (TPC) in the extracts from P. macrocarpa fruit peels were determined using the procedure outlined [13]. Briefly, 1 mL of the extract solution (10 mg of extract dissolved in 2 mL of distilled water) was mixed with 0.2 mL of Folin-Ciocalteu reagent. The mixture was left for 5 min at room temperature and thereafter, 0.6 mL of 0.2 mM Na2 CO3 solution was added. The mixture was further allowed to stand in the dark at room temperature for the next 2 h. After incubation, the absorbance was measured using a Spectrophotometer (U-1800, Japan) at 765 nm. Then, the sample concentration was calculated from the gallic acid (100–100 mg/mL) standard curve equation and the result was expressed as mg gallic acid equivalents per gram of dried weight sample (mg GAE/g d.w.). Distilled water was used as the blank and analyses were repeated thrice. 2.4. Determination of antioxidant activity The antioxidant ability of the P. macrocarpa fruit peels’ extract was determined using the procedure described by Yayah et al. with slight modification [17]. DPPH was dissolved in methanol to the concentration of 0.1 mM DPPH. A 0.2 mL of the extract solution (10 mg of extract dissolved 1 mL of distilled water) was mixed with 2 mL of 0.1 mM DPPH solution. The mixture was left to incubate for 30 min and the absorbance was determined using a Spectrophotometer at 517 nm. Methanol was used as the blank and the scavenging capacity was calculated using Eq. (1).
Scavenging e f f ect =
A0 − A1 × 100% A0
(1)
where A0 was the absorbance of the control reaction and A1 was the absorbance of the sample of the extract. 2.5. Data analysis The experiments trials were repeated thrice, and average results with the standard deviation were computed using MS R Excel 2013 . The significant level was taken at p < 0.05. 3. Data, value and validation 3.1. Effect of process parameters on extracted yield of P. macrocarpa peels The effects of three processing parameters namely irradiation time, microwave temperature and microwave power level on the extraction yield were discussed in this section. The influence of different irradiation time (0.5–10 min) on the extraction yield is illustrated in Fig. 1. As can be seen, the maximum recovery of extraction yield of 55.58 ± 0.42% was at 1 min of irradiation time, after that the yield started to decrease sharply to the lowest amount of 33.83 ± 0.67% within 10 min of irradiation time. At the beginning when the irradiation time was at 0.5 min, the extraction yield was nearly the same as 3 min irradiated sample at around 45.83 ± 0.67 and 45.25 ± 0.42%, respectively. Further increasing of irradiation time more than 3 min resulted in a sharp decline in the yield obtained. This result is in a good agreement with those found by Alara et al. [13]. Moreover, the efficiency of microwave heating depends on the extraction time and temperature. Increasing the
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O.R. Alara, S.K.A. Mudalip and N.H. Abdurahman et al. / Chemical Data Collections 24 (2019) 100277
Fig. 2. Effect of microwave temperature on the extraction yield. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
microwave temperature and irradiation time results in a good penetration of heat through the sample and enhances contact between solvent and sample. However, longer extraction time may lead to destruction and decomposition of the sample and hence result in low yield [18]. The decline of extraction yield with the extraction time after 80s was also reported [19]. The distinguishing advantage of this microwave-assisted extraction from others is its ability to rapidly heat the sample solvent mixture. Also, the extraction can be performed in a closed vessel at elevated temperatures and the targeted compounds are extracted from the sample matrix. When comparing this method with the conventional extraction method, it is about 10 times smaller in the amount of solvent used. Also, sample throughput is increased as several samples can be extracted simultaneously [20]. Besides the extraction time, the temperature is also an important factor in microwave-assisted extraction. In a dielectric material, the temperature is essential for controlling the quantity of energy and converting it to heat. Fig. 2 shows the effect of temperature on the yield of extraction. The yield of bioactive compounds from P. macrocarpa peels obtained at different microwave temperatures (60–100 °C). As seen, a mountainous peak observed throughout the applied temperature ranges. In the beginning, when the heating temperature increased from 60 to 70 °C, the recovery of yield increased as well from 47.50 ± 0.83 to 53.33 ± 1.00 °C. Furthermore, the addition of 10 °C resulted in the highest amount of yield 58.92 ± 0.42 °C. However, when the temperature rises to 90 and 100 °C, the amount of yield started to decrease dramatically from 49.83 ± 1.00 to 41.25 ± 0.92 °C, respectively. Overall, the results implied that 80 °C was the best heating condition for P. macrocarpa peels samples to recover the maximum extraction yield. According to Lovric´ et al., a proper selection of microwave temperature is important to obtain a desirable amount of yield [18]. At higher temperature, the cellular structure of plant matrix can quickly absorb the solvent leading to the rupturing of cell walls, releasing of the components to the solvent and hence results to higher extraction yield. On the other hand, higher temperature more than a certain point can cause to the degradation of thermolabile materials and evaporation of volatile components, which finally results to the reduction of yield [21,22]. In a microwave-assisted extraction, microwave power determines the absorption of microwave energy through the sample. Microwave power is directly proportional to the temperature of extraction. In this study, the amount of extraction yield as a function of microwave power was evaluated. Fig. 3 indicates the influence of different microwave power levels (20 0–60 0 W) on the extraction yield of P. macrocarpa fruit peels. It can be clearly seen that the initial yield obtained at 200 W was 45.33 ± 1.17 W. Following, the increasing of microwave power to 300 W resulted in the highest amount of yield throughout the process. Further increase in the microwave power from 400 to 600 W, eventuated to the yield reduction from 42.42 ± 0.92 W to 31.25 ± 0.42 W. As stated by Xue et al., high microwave power is able to break the cell walls of plant matrix efficiently and diffuse route of interior components to the extraction solvent [23]. However, increasing the microwave power to higher levels means increasing the temperature inside the microwave, which results in the degradation and destruction of plant cells and finally lower the yield. 3.2. Effect of process parameters on total phenolic content Fig. 4 shows the effect of different irradiation time (0.5–10 min) on the total phenolic content of P. macrocarpa fruit peel extract. The obtained results indicate that the recovery yield of TPC increased with increasing the irradiation time from (0.5 to 1 min) at the beginning of the process from 84.66 ± 1.86 to 97.88 ± 1.20 mg GAE/g d.w. However, increasing the time of irradiation to 3, 5 and 10 min resulted in the reduction of TPC yield as 93.58 ± 1.07 mg GAE/g d.w., 86.80 ± 1.00 mg GAE/g d.w. and 83.16 ± 1.05 mg GAE/g d.w, respectively. Longer irradiation times might have led to the degradation of phenolic
O.R. Alara, S.K.A. Mudalip and N.H. Abdurahman et al. / Chemical Data Collections 24 (2019) 100277
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Fig. 3. Effect of microwave power on extraction yield. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
Fig. 4. Changes in TPC and DPPH inhibition as influenced by irradiation time. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
compounds in the extracts. These findings are in a good agreement with previous results found by Dahmoune et al. and Alara et al. [13,24]. Thus, the maximum yield of phenolic compounds (97.88 ± 1.00 mg GAE/g d.w) was obtained at 1 min of irradiation time. In addition, with the effects of irradiation time on the yield of TPC, this study found that antioxidant activity of the extract can also be affected by the time of irradiation. Fig. 4 demonstrates the influence of irradiation time (0.5–10 min) on the antioxidant activity of P. macrocarpa fruit peel extracts. As can be seen, the percentage of DPPH inhibition against the irradiation time followed the same trend with TPC yield. In the beginning, rising the irradiation time from half of a min to 1 min increased the percentage of antioxidant activity from 46.47 to 55.58%, respectively. After the observation of the highest peak of antioxidant activity at 1 min, the trend of DPPH inhibition percentage dropped down by the irradiation times of 3, 5 and 10 min at 42.19, 36.80 and 34.01%, respectively. As reported by Lovric´ et al., extended extraction time can cause the degradation of enzymes, hence a reduction in the yield of TPC and antioxidant activity [18]. Based on the previous studies reported, the TPC and antioxidant activity of medicinal plants can be affected by various factors in a microwave-assisted extraction. Therefore, the effects of different temperatures (60–100 °C) on TPC and antioxidant activity of the extract are also studied. Fig. 5 represents the influence of microwave temperature on the TPC and antioxidant activity of the extract. The effect of temperature on TPC and antioxidant activity of the extract followed the same trend as the extraction yield discussed in the previous section. Rising the microwave temperature from 60 to 70 °C, resulted in the increase in the yield recovery of both TPC and percentage of DPPH inhibition from 89.05 to 92.02 mg GAE/g d.w. and 47.58 to 52.6%, respectively. The maximum yields of TPC and antioxidant activity were recorded at 80 °C which is
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O.R. Alara, S.K.A. Mudalip and N.H. Abdurahman et al. / Chemical Data Collections 24 (2019) 100277
Fig. 5. Changes in TPC and DPPH inhibition as influenced by temperature. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
Fig. 6. Changes in TPC and DPPH inhibition as influenced by microwave power. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
100.10 mg GAE/g d.w. and 58.74%, respectively. Further enhancement in the process temperature to 90 and 100 °C declined the recovery yields of both TPC and percentage of DPPH inhibition as recorded at 91.52 ± 1.03 to 87.77 ± 0.79 mg GAE/g d.w. and 51.67 ± 0.37 to 43.68 ± 0.93%, respectively. These results obtained similar trends as found [13]. For a better evaluation of MAE process parameters effects on the TPC and antioxidant activity of P. macrocarpa peel extracts, this study also performed the influence of different microwave power levels (20 0–60 0 W) on the recovery yields of TPC and antioxidant activity. Fig. 6 shows that how different levels of microwave power influenced on the TPC and antioxidant activity of the extract. As seen, the microwave power level affected the same as obtained in the extraction yield. By the initial microwave power level of 200 W the TPC and antioxidant activity achieved at 94.49 ± 0.67 mg GAE/g d.w. and 45.17 ± 0.558%, respectively, while a slight increase in the power of microwave to 300 W resulted to the maximum peaks for both at 102.60 ± 1.17 mg GAE/g d.w. and 61.15 ± 0.929%, respectively. Moreover, the results indicated that further enhancement in the level of microwave power from 400 to 600 W, declined the recovery yields of TPC and antioxidant activity from 91.24 ± 1.08 to 81.66 ± 0.78 mg GAE/g d.w. and from 42.57±1.30 to 31.6 ± 1.115%, respectively. As claimed by Xue et al., increasing the level of microwave power has a strong effect on the level of the temperature inside a system [23]. Higher levels of microwave power forcefully destruct the cell walls of plants and may cause to the evaporation of volatile compounds.
O.R. Alara, S.K.A. Mudalip and N.H. Abdurahman et al. / Chemical Data Collections 24 (2019) 100277
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4. Conclusion In the present study, the microwave-assisted extraction of P. macrocarpa fruit peels was investigated. The effects of different processing parameters such as irradiation time, microwave temperature and power on the extraction yield, the recovery yield of total phenolic content and antioxidant activity of the extract were also performed. The results implied that increasing all the parameters including irradiation time, microwave temperature and power to certain points resulted in the enhancement of yield recoveries such as extraction yield, TPC and antioxidant activity of the extract. Based on the parameter of time at 1 min, the optimum points for extraction yield, TPC and antioxidant activity of the extract were recorded at 55.58 ± 0.42%, 97.88 ± 0.79 mg GAE/g d.w. and 55.58 ± 0.56%, respectively. In regards to the temperature at 80 °C, the best condition for extraction yield, TPC and antioxidant activity of the extract were achieved at 58.92 ± 0.417%, 100.10 ± 1.14 mg GAE/g d.w. and 58.74 ± 0.74%, respectively. Results also revealed that microwave power has a strong effect on the extraction yields. As the optimum microwave power level (300 W) resulted to the optimum conditions for extraction yield, TPC and antioxidant activity of the extract at 61.25 ± 0.917%, 102.6 ± 1.167 mg GAE/g d.w and 61.15 ± 0.929%, respectively. Based on the optimized conditions of the results, MAE can be accounted a satisfying method for plant extraction, as this method requires less amount of solvent, low microwave energy and shorter time with high efficiency of the extraction. Therefore, these results suggest that extraction of P. macrocarpa fruit peels through the MAE method can be explored as a promising source of antioxidants in the food and pharmaceutical industries. Declaration of Competing Interest We have no conflict of interest to declare. Acknowledgment This study was supported by Universiti Malaysia Pahang under the Internal Grant Research Scheme RDU1803107. References [1] WHO, WHO traditional medicine strategy, Altern. Integr. Med. 1 (1) (2013) 1–78. [2] M. Mukhtar, M. Arshad, M. Ahmad, R.J. Pomerantz, B. Wigdahl, Z. Parveen, Antiviral potentials of medicinal plants, Virus Res 131 (2) (2008) 111–120. [3] C.-H. Chan, R. Yusoff, G.-C. Ngoh, F.W.-L. Kung, Microwave-assisted extractions of active ingredients from plants, J. Chromatogr. A 1218 (37) (2011) 6213–6225. [4] R. Hendra, S. Ahmad, A. Sukari, M.Y. Shukor, Flavonoid analyses and antimicrobial activity of various parts of Phaleria macrocarpa (Scheff.) boerl fruit, Int. J. Mol. Sci. 12 (6) (2011) 3422–3431. [5] D. Andrean, S. Prasetyo, A.P. Kristijarti, T. Hudaya, The extraction and activity test of bioactive compounds in Phaleria macrocarpa as antioxidants, Procedia Chem 9 (2014) 94–101. [6] O.R. Alara, S.K. Abdul Mudalip, O.A. Olalere, Optimization of mangiferin extracted from Phaleria macrocarpa fruits using response surface methodology, J. Appl. Res. Med. Aromat. Plants 5 (2017) 82–87. [7] M.M. Lay, S.A. Karsani, S. Mohajer, S.N. Abd Malek, Phytochemical constituents, nutritional values, phenolics, flavonols, flavonoids, antioxidant and cytotoxicity studies on Phaleria macrocarpa (Scheff.) Boerl fruits, BMC Complement. Altern. Med. 14 (1) (2014) 1–12. [8] O.R. Alara, N.H. Abdurahman, O.A. Olalere, Ethanolic extraction of flavonoids, phenolics and antioxidants from Vernonia amygdalina leaf using two-level factorial design, J. King Saud Uni. – Sci. (2017) Article in Press. [9] W. Kim, B. Veriansyah, Y. Lee, J. Kim, J. Kim, Extraction of mangiferin from Mahkota Dewa (Phaleria macrocarpa) using subcritical water, J. Ind. Eng. Chem. 16 (3) (2010) 425–430. [10] S. Oshimi, K. Zaima, Y. Matsuno, Y. Hirasawa, T. Lizuka, G. Indrayanto, N.C. Zaini, H. Morita, Studies on the constituents from the fruits of Phaleria macrocarpa, J. Nat. Med. 62 (2) (2008) 207–210. [11] Y. Zhang, X. Xu, H. Liu, Chemical constituents from Mahkota Dewa, J. Asian Nat. Prod. Res. 8 (2006) 119–123. [12] O.R. Alara, J.A. Alara, O.A. Olalere, Review on Phaleria macrocarpa pharmacological and phytochemical properties, Drug Des 5 (3) (2016) 134–138. [13] O.R. Alara, N.H. Abdurahman, C.I. Ukaegbu, N.H. Azhari, Vernonia cinerea leaves as the source of phenolic compounds, antioxidants, and anti-diabetic activity using microwave-assisted extraction technique, Ind. Crops Prod. 122 (12) (2018) 533–544. [14] A. Ghasemzadeh, N. Ghasemzadeh, Flavonoids and phenolic acids: role and biochemical activity in plants and human, J. Med. Plants Res. 5 (31) (2011) 6697–6703. [15] M. Devgun, A. Nanda, S.H. Ansari, Comparison of conventional and non conventional methods of extraction of heartwood of Pterocarpus marsupium Roxb, Acta Pol. Pharm. - Drug Res. 69 (3) (2012) 475–485. [16] G. Wang, P. Su, F. Zhang, X. Hou, Y. Yang, Z. Guo, Comparison of microwave-assisted extraction of aloe-emodin in aloe with Soxhlet extraction and ultrasound-assisted extraction, Sci. China Chem. 54 (1) (2011) 231–236. [17] W. Yayah, T. Hudaya, S. Prasetyo, J. Wangsa, Pretreatment and optimization studies on the extraction of antioxidant components from Phaleria macrocarpa fruit, ASEAN Eng. J. Part B 5 (1) (2015) 46–60. ´ [18] V. Lovric´ , P. Putnik, D.B. Kovacˇ evic´ , M. Jukic´ , V. Dragovic-uzelac , Effect of microwave-assisted extraction on the phenolic compounds and antioxidant capacity of blackthorn flowers, Food Technol. Biotechnol. 55 (2) (2017) 243–250. [19] J.-L. Liu, L.-Y. Li, G.-H. He, Optimization of microwave-assisted extraction conditions for five major bioactive compounds from flos sophorae immaturus (Cultivars of sophora japonica L.) using response surface methodology, Mol 21 (3) (2016) 127. [20] C.S. Eskilsson, E. Bjorklund, Analytical-scale microwave-assisted extraction, J. Chromatogr. A 902 (20 0 0) 227–250. [21] J. Azmir, I.S.M. Zaidul, M.M. Rahman, K.M. Sharif, A. Mohamed, F. Sahena, A.K.M. Omar, Techniques for extraction of bioactive compounds from plant materials: a review, J. Food Eng. 117 (4) (2013) 426–436. [22] J.-H. Maeng, H.M. Shahbaz, K. Ameer, Y. Jo, J.-H. Kwon, Optimization of microwave-assisted extraction of bioactive compounds from Coriolus versicolor mushroom using response surface methodology, J. Food Process Eng. 40 (2) (2017) 12421. [23] H. Xue, H. Xu, X. Wang, L. Shen, H. Liu, C. Liu, Q. Qin, Effects of microwave power on extraction kinetic of anthocyanin from blueberry powder considering absorption of microwave energy, J. Food Qual. 1 (2018) 1–13. [24] F. Dahmoune, B. Nayak, K. Moussi, H. Remini, K. Madani, Optimization of microwave-assisted extraction of polyphenols from Myrtus communis L. leaves, Food Chem 166 (2015) 585–595.
Contents lists available at ScienceDirect
Chemical Data Collections journal homepage: www.elsevier.com/locate/cdc
Data Article
Data on parametric influence of microwave-assisted extraction on the recovery yield, total phenolic content and antioxidant activity of Phaleria macrocarpa fruit peel extract Oluwaseun Ruth Alara a, Siti Kholijah Abdul Mudalip a,b,∗, Nour Hamid Abdurahman a,b, Mohammed Saeed Mahmoud a, Emmanuel Ogo-Oluwa Obanijesu c a
Faculty of Chemical and Natural Resources Engineering, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300, Gambang, Pahang, Malaysia Centre of Excellence for Advanced Research in Fluid Flow, Universiti Malaysia Pahang, 26300 Gambang, Pahang, Malaysia c School of Education, Edith Cowan University, Joondalup Campus, Perth, Australia b
a r t i c l e
i n f o
a b s t r a c t
Article history: Received 6 February 2019 Revised 10 September 2019 Accepted 10 September 2019 Available online 11 September 2019 Keywords: Microwave-assisted extraction Phaleria macrocarpa Antioxidant Total phenolic content Yield
Phaleria macrocarpa, commonly known as Mahkota dewa is a well-known medicinal plant native to Malaysia and Indonesia. P. macrocarpa has been used as traditional medicine for the treatment of many diseases for a long time. In this study, P. macrocarpa peels’ bioactive compounds were extracted using microwave-assisted extraction method. The effects of different process parameters such as irradiation time (0.5, 1, 3, 5, and 10 min), microwave temperatures (60, 70, 80, 90, and 100 °C) and microwave power (20 0, 30 0, 40 0, 50 0, and 600 W) on the extraction yield were investigated. Moreover, the antioxidant activity and total phenolic (TPC) content of the extract were estimated. The results reflected that the extraction yields, antioxidant activity and total phenolic content increased with increasing levels of process parameters to certain conditions where highest yields were attained. However, the best conditions of processing parameters that resulted to the highest amount of yield (61.25%) were 1 min, 80 °C and 300 W. The highest amount of antioxidant activity and TPC yield were 61.15±0.93% and 102.60±1.17 mg GAE/g d.w, respectively. These illustrated that P. macrocarpa peels can serve as a good source of antioxidant. © 2019 Elsevier B.V. All rights reserved.
Specification Table
Subject area: Data category: Data acquisition: Format: Data type: Procedure:
∗
Natural product research Microwave-assisted extraction parameters study, Antioxidant Spectrophotometric analysis Figures Analysed The influences of MAE parameters on the recovery of total phenolic content and antioxidant was studied.
Corresponding author. E-mail address: [email protected] (S.K.A. Mudalip).
https://doi.org/10.1016/j.cdc.2019.100277 2405-8300/© 2019 Elsevier B.V. All rights reserved.
2
O.R. Alara, S.K.A. Mudalip and N.H. Abdurahman et al. / Chemical Data Collections 24 (2019) 100277
1. Rationale According to the World Health Organization (WHO), about 80% of the world’s population uses herbal products either as food supplements or as alternative medicine [1]. Mukhtar et al. reported that about 25% of the commonly used medicines contain compounds isolated from plants [2]. In Malaysia, the vast rainforests are blessed with various types of plants with medicinal value. This had therefore found a special place in the treatment of many life-threatening diseases. Chua et al. reported that over 12,0 0 0 of both higher and lower species of plants are available in Peninsular Malaysia with about 16% used for medicinal purposes [3]. There is still an incredible number of unexplored functional plants that can be used in medicine. The consumption of plant foods, particularly fruits, vegetables and cereal grains is therefore encouraged because they render beneficial health effects. An example of this plants is Mahkota Dewa (Phaleria macrocarpa) which is mainly found in the Southeast Asia region, it is commonly referred to as God’s crown [4]. It is important medicinal thick and evergreen plant usually grown in the tropical region. P. macrocarpa trees have the height ranging from 1 to 18 m and leaf length and width ranging from 7 to 10 cm and 3 to 5 cm, respectively. Its fruits are usually grown on trucks and branches and changes from green to red when ripe [5]. This plant has been used in the treatment of several diseases such as Diabetes mellitus, cancer, hemorrhoids, and impotence. This is due to its anti-oxidation, antihistamine and antitumor effects [6]. P. macrocarpa is being used in Indonesia as one of the major ingredients in some brands of tea and healthy drink. Different bioactive compounds such as Mahkoside A, luteolin, tangeritin, quercetin, kaempferol, myricetin, isorhamnetin, pachypodol, hesperetin, naringenin, eriodictyol, catechins and epicatechins, and among others had been previously isolated from Mahkota Dewa [7]. Moreover, recent studies from China, Japan, Malaysia, and Indonesia showed that there are several compounds that were isolated from the fruit extracts of P. macrocarpa. These include dodecanoic acid, palmitic acid, ethyl stearate, sucrose, vasorelaxant icariside C3, and mangiferin [8–11]. One study reported that P. macrocarpa has shown the potential effect of improving male fertility [12]. With the capability of P. macrocarpa in healing and traditionally curing certain diseases, it shows that this plant could be a new natural source for antioxidants molecules. Due to the medicinal value of P. macrocarpa, its extracts have been applied in many areas of food and drug, part of which are in the production of herbal tea, cosmetics, food, and medicine. According to Alara et al., the investigations on medicinal plants are recently achieving more interest due to their potential antioxidant activity and total phenolic contents [13]. These compounds have several biological properties which include anti-inflammation, antioxidant, antimalarial, anti-diabetic, anti-fungi, antimicrobial, and many other benefits. Phenolic compounds are responsible for the amazing taste, flavor, and antioxidant properties found in the leaves and fruits of many medicinal plants [14]. Several secondary metabolites such as phenolic acid and phenolic hydroxyl are known to be active compounds with natural antioxidant properties that are capable of scavenging free superoxide radicals, anti-aging and reducing the risk of cancer. Several extraction methods (conventional and non-conventional) are being used in the extraction of bioactive compounds from plant matrix. Conventional techniques such as maceration, Soxhlet extraction, and solvent extraction are traditionally applied for extraction of plant-based bioactive compounds. Researchers have also studied the efficiency of unconventional methods including ultrasound-assisted extraction and microwave-assisted extraction. Among the non-unconventional methods is microwave-assisted extraction, which has been a novel method that drew the attention of researchers recently because of its shortened extraction time, higher quality of yield and reduced solvent consumption [15,16]. Therefore, this study focused on the use of microwave-assisted extraction technique in the extraction of bioactive compounds from P. macrocarpa fruit peels. 2. Procedure 2.1. Plant materials, chemicals and reagents Dried P. macrocarpa fruit peels were purchased from Ethno Resources Sdn Bhd, Selangor. The sample was ground into a smaller size (0.1 mm) using a Grindomix grinder (GM-200 model, Germany). Analytical grade methanol (99 wt%), gallic acid, Folin-Ciocalteu phenol reagent, 2,2-diphenyl-picrylhydrazyl (DPPH), and sodium carbonate anhydrous were purchased from Merck Sdn Bhd, Selangor. All the reagents were used without further purification but some of the chemical dilutions were conducted according to the experimental protocol. 2.2. Microwave-assisted extraction The extraction process was conducted using an easy control ETHOS-microwave extractor (ATC-300, North America). The microwave system is made up of a programmable auxiliary input system which was used to monitor and set the parameters of extraction. This was equipped with a temperature control optical fiber with a maximum output power of 10 0 0 W at 1 atm. The cooling system has the inlet and outlet port to maintain a boiling temperature balance and microwave power level. Briefly, 6 g of a blended sample of P. macrocarpa fruit peels was extracted using a distilled water in accordance with the OFAT design at a feed-to-solvent ratio of 60 g/L. The mixture was then unloaded from the microwave cavity, the extract was filtered and concentrated to dryness using a rotary evaporator (Buchi-R-200, Germany). The percentage of extraction yield was determined, and the extract was stored at 4ºC until further analysis.
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Fig. 1. Changes in extraction yields as influenced by irradiation time. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
2.3. Determination of phenolic content The total phenolic contents (TPC) in the extracts from P. macrocarpa fruit peels were determined using the procedure outlined [13]. Briefly, 1 mL of the extract solution (10 mg of extract dissolved in 2 mL of distilled water) was mixed with 0.2 mL of Folin-Ciocalteu reagent. The mixture was left for 5 min at room temperature and thereafter, 0.6 mL of 0.2 mM Na2 CO3 solution was added. The mixture was further allowed to stand in the dark at room temperature for the next 2 h. After incubation, the absorbance was measured using a Spectrophotometer (U-1800, Japan) at 765 nm. Then, the sample concentration was calculated from the gallic acid (100–100 mg/mL) standard curve equation and the result was expressed as mg gallic acid equivalents per gram of dried weight sample (mg GAE/g d.w.). Distilled water was used as the blank and analyses were repeated thrice. 2.4. Determination of antioxidant activity The antioxidant ability of the P. macrocarpa fruit peels’ extract was determined using the procedure described by Yayah et al. with slight modification [17]. DPPH was dissolved in methanol to the concentration of 0.1 mM DPPH. A 0.2 mL of the extract solution (10 mg of extract dissolved 1 mL of distilled water) was mixed with 2 mL of 0.1 mM DPPH solution. The mixture was left to incubate for 30 min and the absorbance was determined using a Spectrophotometer at 517 nm. Methanol was used as the blank and the scavenging capacity was calculated using Eq. (1).
Scavenging e f f ect =
A0 − A1 × 100% A0
(1)
where A0 was the absorbance of the control reaction and A1 was the absorbance of the sample of the extract. 2.5. Data analysis The experiments trials were repeated thrice, and average results with the standard deviation were computed using MS R Excel 2013 . The significant level was taken at p < 0.05. 3. Data, value and validation 3.1. Effect of process parameters on extracted yield of P. macrocarpa peels The effects of three processing parameters namely irradiation time, microwave temperature and microwave power level on the extraction yield were discussed in this section. The influence of different irradiation time (0.5–10 min) on the extraction yield is illustrated in Fig. 1. As can be seen, the maximum recovery of extraction yield of 55.58 ± 0.42% was at 1 min of irradiation time, after that the yield started to decrease sharply to the lowest amount of 33.83 ± 0.67% within 10 min of irradiation time. At the beginning when the irradiation time was at 0.5 min, the extraction yield was nearly the same as 3 min irradiated sample at around 45.83 ± 0.67 and 45.25 ± 0.42%, respectively. Further increasing of irradiation time more than 3 min resulted in a sharp decline in the yield obtained. This result is in a good agreement with those found by Alara et al. [13]. Moreover, the efficiency of microwave heating depends on the extraction time and temperature. Increasing the
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Fig. 2. Effect of microwave temperature on the extraction yield. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
microwave temperature and irradiation time results in a good penetration of heat through the sample and enhances contact between solvent and sample. However, longer extraction time may lead to destruction and decomposition of the sample and hence result in low yield [18]. The decline of extraction yield with the extraction time after 80s was also reported [19]. The distinguishing advantage of this microwave-assisted extraction from others is its ability to rapidly heat the sample solvent mixture. Also, the extraction can be performed in a closed vessel at elevated temperatures and the targeted compounds are extracted from the sample matrix. When comparing this method with the conventional extraction method, it is about 10 times smaller in the amount of solvent used. Also, sample throughput is increased as several samples can be extracted simultaneously [20]. Besides the extraction time, the temperature is also an important factor in microwave-assisted extraction. In a dielectric material, the temperature is essential for controlling the quantity of energy and converting it to heat. Fig. 2 shows the effect of temperature on the yield of extraction. The yield of bioactive compounds from P. macrocarpa peels obtained at different microwave temperatures (60–100 °C). As seen, a mountainous peak observed throughout the applied temperature ranges. In the beginning, when the heating temperature increased from 60 to 70 °C, the recovery of yield increased as well from 47.50 ± 0.83 to 53.33 ± 1.00 °C. Furthermore, the addition of 10 °C resulted in the highest amount of yield 58.92 ± 0.42 °C. However, when the temperature rises to 90 and 100 °C, the amount of yield started to decrease dramatically from 49.83 ± 1.00 to 41.25 ± 0.92 °C, respectively. Overall, the results implied that 80 °C was the best heating condition for P. macrocarpa peels samples to recover the maximum extraction yield. According to Lovric´ et al., a proper selection of microwave temperature is important to obtain a desirable amount of yield [18]. At higher temperature, the cellular structure of plant matrix can quickly absorb the solvent leading to the rupturing of cell walls, releasing of the components to the solvent and hence results to higher extraction yield. On the other hand, higher temperature more than a certain point can cause to the degradation of thermolabile materials and evaporation of volatile components, which finally results to the reduction of yield [21,22]. In a microwave-assisted extraction, microwave power determines the absorption of microwave energy through the sample. Microwave power is directly proportional to the temperature of extraction. In this study, the amount of extraction yield as a function of microwave power was evaluated. Fig. 3 indicates the influence of different microwave power levels (20 0–60 0 W) on the extraction yield of P. macrocarpa fruit peels. It can be clearly seen that the initial yield obtained at 200 W was 45.33 ± 1.17 W. Following, the increasing of microwave power to 300 W resulted in the highest amount of yield throughout the process. Further increase in the microwave power from 400 to 600 W, eventuated to the yield reduction from 42.42 ± 0.92 W to 31.25 ± 0.42 W. As stated by Xue et al., high microwave power is able to break the cell walls of plant matrix efficiently and diffuse route of interior components to the extraction solvent [23]. However, increasing the microwave power to higher levels means increasing the temperature inside the microwave, which results in the degradation and destruction of plant cells and finally lower the yield. 3.2. Effect of process parameters on total phenolic content Fig. 4 shows the effect of different irradiation time (0.5–10 min) on the total phenolic content of P. macrocarpa fruit peel extract. The obtained results indicate that the recovery yield of TPC increased with increasing the irradiation time from (0.5 to 1 min) at the beginning of the process from 84.66 ± 1.86 to 97.88 ± 1.20 mg GAE/g d.w. However, increasing the time of irradiation to 3, 5 and 10 min resulted in the reduction of TPC yield as 93.58 ± 1.07 mg GAE/g d.w., 86.80 ± 1.00 mg GAE/g d.w. and 83.16 ± 1.05 mg GAE/g d.w, respectively. Longer irradiation times might have led to the degradation of phenolic
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Fig. 3. Effect of microwave power on extraction yield. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
Fig. 4. Changes in TPC and DPPH inhibition as influenced by irradiation time. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
compounds in the extracts. These findings are in a good agreement with previous results found by Dahmoune et al. and Alara et al. [13,24]. Thus, the maximum yield of phenolic compounds (97.88 ± 1.00 mg GAE/g d.w) was obtained at 1 min of irradiation time. In addition, with the effects of irradiation time on the yield of TPC, this study found that antioxidant activity of the extract can also be affected by the time of irradiation. Fig. 4 demonstrates the influence of irradiation time (0.5–10 min) on the antioxidant activity of P. macrocarpa fruit peel extracts. As can be seen, the percentage of DPPH inhibition against the irradiation time followed the same trend with TPC yield. In the beginning, rising the irradiation time from half of a min to 1 min increased the percentage of antioxidant activity from 46.47 to 55.58%, respectively. After the observation of the highest peak of antioxidant activity at 1 min, the trend of DPPH inhibition percentage dropped down by the irradiation times of 3, 5 and 10 min at 42.19, 36.80 and 34.01%, respectively. As reported by Lovric´ et al., extended extraction time can cause the degradation of enzymes, hence a reduction in the yield of TPC and antioxidant activity [18]. Based on the previous studies reported, the TPC and antioxidant activity of medicinal plants can be affected by various factors in a microwave-assisted extraction. Therefore, the effects of different temperatures (60–100 °C) on TPC and antioxidant activity of the extract are also studied. Fig. 5 represents the influence of microwave temperature on the TPC and antioxidant activity of the extract. The effect of temperature on TPC and antioxidant activity of the extract followed the same trend as the extraction yield discussed in the previous section. Rising the microwave temperature from 60 to 70 °C, resulted in the increase in the yield recovery of both TPC and percentage of DPPH inhibition from 89.05 to 92.02 mg GAE/g d.w. and 47.58 to 52.6%, respectively. The maximum yields of TPC and antioxidant activity were recorded at 80 °C which is
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Fig. 5. Changes in TPC and DPPH inhibition as influenced by temperature. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
Fig. 6. Changes in TPC and DPPH inhibition as influenced by microwave power. Results are provided as means ± standard deviation. Different alphabets show a significant difference (p < 0.05).
100.10 mg GAE/g d.w. and 58.74%, respectively. Further enhancement in the process temperature to 90 and 100 °C declined the recovery yields of both TPC and percentage of DPPH inhibition as recorded at 91.52 ± 1.03 to 87.77 ± 0.79 mg GAE/g d.w. and 51.67 ± 0.37 to 43.68 ± 0.93%, respectively. These results obtained similar trends as found [13]. For a better evaluation of MAE process parameters effects on the TPC and antioxidant activity of P. macrocarpa peel extracts, this study also performed the influence of different microwave power levels (20 0–60 0 W) on the recovery yields of TPC and antioxidant activity. Fig. 6 shows that how different levels of microwave power influenced on the TPC and antioxidant activity of the extract. As seen, the microwave power level affected the same as obtained in the extraction yield. By the initial microwave power level of 200 W the TPC and antioxidant activity achieved at 94.49 ± 0.67 mg GAE/g d.w. and 45.17 ± 0.558%, respectively, while a slight increase in the power of microwave to 300 W resulted to the maximum peaks for both at 102.60 ± 1.17 mg GAE/g d.w. and 61.15 ± 0.929%, respectively. Moreover, the results indicated that further enhancement in the level of microwave power from 400 to 600 W, declined the recovery yields of TPC and antioxidant activity from 91.24 ± 1.08 to 81.66 ± 0.78 mg GAE/g d.w. and from 42.57±1.30 to 31.6 ± 1.115%, respectively. As claimed by Xue et al., increasing the level of microwave power has a strong effect on the level of the temperature inside a system [23]. Higher levels of microwave power forcefully destruct the cell walls of plants and may cause to the evaporation of volatile compounds.
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4. Conclusion In the present study, the microwave-assisted extraction of P. macrocarpa fruit peels was investigated. The effects of different processing parameters such as irradiation time, microwave temperature and power on the extraction yield, the recovery yield of total phenolic content and antioxidant activity of the extract were also performed. The results implied that increasing all the parameters including irradiation time, microwave temperature and power to certain points resulted in the enhancement of yield recoveries such as extraction yield, TPC and antioxidant activity of the extract. Based on the parameter of time at 1 min, the optimum points for extraction yield, TPC and antioxidant activity of the extract were recorded at 55.58 ± 0.42%, 97.88 ± 0.79 mg GAE/g d.w. and 55.58 ± 0.56%, respectively. In regards to the temperature at 80 °C, the best condition for extraction yield, TPC and antioxidant activity of the extract were achieved at 58.92 ± 0.417%, 100.10 ± 1.14 mg GAE/g d.w. and 58.74 ± 0.74%, respectively. Results also revealed that microwave power has a strong effect on the extraction yields. As the optimum microwave power level (300 W) resulted to the optimum conditions for extraction yield, TPC and antioxidant activity of the extract at 61.25 ± 0.917%, 102.6 ± 1.167 mg GAE/g d.w and 61.15 ± 0.929%, respectively. Based on the optimized conditions of the results, MAE can be accounted a satisfying method for plant extraction, as this method requires less amount of solvent, low microwave energy and shorter time with high efficiency of the extraction. Therefore, these results suggest that extraction of P. macrocarpa fruit peels through the MAE method can be explored as a promising source of antioxidants in the food and pharmaceutical industries. 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