FRIN-03350; No of Pages 6 Food Research International xxx (2010) xxx–xxx

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Review

Extraction and pharmacological properties of bioactive compounds from longan (Dimocarpus longan Lour.) fruit — A review Bao Yang a, Yueming Jiang a,⁎, John Shi b, Feng Chen c, Muhammad Ashraf d a

Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, People's Republic of China Guelph Food Research Center, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario, Canada N1G 5C9 Department of Food Science and Human Nutrition, Clemson University, Clemson, SC 29634, USA d Department of Botany, Faculty of Sciences, University of Agriculture, Faisalabad 38040, Pakistan b c

a r t i c l e

i n f o

Article history: Received 1 September 2010 Accepted 10 October 2010 Available online xxxx Keywords: Longan Dimocarpus longan Lour. Fruit Extraction Bioactive compound Pharmacological activities

a b s t r a c t Mature longan (Dimocarpus longan Lour.) fruit has a succulent, edible and white aril, which has gained popularity as an exotic fruit in temperate regions. It is prized on the international market resulting in an increased production with significant contributions to local economic development. Longan fruit contains significant amounts of bioactive compounds such as corilagin, ellagic acid and its conjugates, 4-O-methylgallic acid, flavone glycosides, glycosides of quercetin and kaempferol, ethyl gallate 1-β-O-galloyl-D-glucopyranose, grevifolin and 4-O-α-Lrhamnopyranosyl-ellagic acid. The fruit has been used in the traditional Chinese medicinal formulation, serving as an agent in relief of neural pain and swelling. The application of ultrasonic-assisted extraction or high pressureassisted extraction greatly increases the yield from longan pericarp or seeds. In recent years, some pharmacological activities such as anti-tyrosinase, anti-glycated and anticancer activities, and memoryenhancing effects of longan aril, pericarp or seed extract have been found, implicating a significant contribution to human health. Regarding the increasing cultivation area and increasing quantity of longan fruit in the world, further utilization of this fruit is expected in an effort to use more efficiently the inherent bioactive compounds. The paper reviews the recent advances in the extraction and pharmacological activities of bioactive compounds from longan fruit. Some novel pharmacological potential of longan fruit is also discussed in this paper. © 2010 Elsevier Ltd. All rights reserved.

Contents 1. 2.

Introduction . . . . . . . . . . . . . . . . Extraction of bioactive compounds . . . . . 2.1. Conventional extraction . . . . . . . 2.2. Ultrasonic-assisted extraction . . . . 2.3. High pressure-assisted extraction. . . 3. Nutritional and phytochemical compositions. 3.1. Nutrients . . . . . . . . . . . . . . 3.2. Phytochemicals . . . . . . . . . . . 4. Pharmacological properties . . . . . . . . . 4.1. Antioxidant activity . . . . . . . . . 4.2. Anti-tyrosinase activity . . . . . . . 4.3. Anti-glycated activity . . . . . . . . 4.4. Potential anticancer activity . . . . . 5. Other beneficial effects . . . . . . . . . . . 6. Prospects . . . . . . . . . . . . . . . . . Acknowledgements . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . .

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⁎ Corresponding author. Tel.: + 86 20 37252525; fax: + 86 20 37252831. E-mail address: [email protected] (Y. Jiang). 0963-9969/$ – see front matter © 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodres.2010.10.019

Please cite this article as: Yang, B., et al., Extraction and pharmacological properties of bioactive compounds from longan (Dimocarpus longan Lour.) fruit — A review, Food Research International (2010), doi:10.1016/j.foodres.2010.10.019

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B. Yang et al. / Food Research International xxx (2010) xxx–xxx

1. Introduction Longan (Dimocarpus longan Lour.) is a subtropical evergreen tree belonging to the family Sapindaceae (Huang, 1995; Tindall, 1994). Longan fruit has a thin, leathery and indehiscent pericarp surrounding a succulent edible aril with a large dark brown seed. Longan fruit has gained popularity as an exotic fruit in temperate regions, and is prized on world markets with strong demand for its desirable flavour and semi-translucent to white aril (Jiang, Zhang, Joyce, & Ketsa, 2002). The fruit is grown commercially in many countries, including China and Thailand, which account for most commercial longan production (Huang, Huang, & Zeng, 2005). Longan production has increased over recent decades because of great improvements in agronomic practices and other aspects of crop management (Huang et al., 2005; Jiang et al., 2002). Increasing production of longan fruit raises prospects for further utilization for this crop. Longan fruit is rich in carbohydrates, protein, fiber, fat, vitamin C, amino acids, and minerals. The fruit has been used traditionally in Chinese medicinal formulation, serving as a common agent in relief of neural pain and swelling. In recent years, the extract from longan fruit including aril, pericarp and seed, has exhibited excellent antioxidant ability and good anti-tyrosinase and anticancer activities (Chung, Lin, Chou, & Hsu, 2010; de Assis et al., 2009; Park et al., 2010; Prasad et al., 2009; Rangkadilok et al., 2007; Soong & Barlow, 2004; Yang, Zhao, & Jiang, 2009; Yang, Zhao, Shi, Yang, & Jiang, 2008c). Thus, longan fruit can be used as a readily accessible source of natural antioxidants and/ or a possible supplement in the food or pharmaceutical industries. To better utilize the longan fruit, the paper reviews the recent advances in the extraction of bioactive compounds present in the fruit and their corresponding biological activities. Some novel pharmacological potential of longan fruit is also discussed in the paper. The paper will give the interested readers more insights of longan fruit, and help relevant farmers and industries to better utilize this fruit in the future. 2. Extraction of bioactive compounds Extraction is the most important step in isolating different types of bioactive compounds from fruits and vegetables. The ideal extraction method should be quantitative, non-destructive and time-saving. There are different extraction methods. Recently, use of green technology like ultrasonic-assisted extraction or high pressureassisted extraction has been reported for efficient extraction of bioactive compounds from longan fruit. 2.1. Conventional extraction It is the traditional way of extracting bioactive compounds from plant tissues, using soxhlet extractor, magnetic stirrer, boiling, maceration, grinding and heat reflux (Yang et al., 2008d). The extraction technique depends largely on the type of solvents, energy input, and agitation to improve the chemical solubility and efficiency of mass transfer. Usually, the conventional extraction requires long extraction time with low extraction yield but high energy consumption. The method is still popular and widely used because it has been well established and is easy to perform and cheap to operate. He et al. (2009) reported the phenol contents of 12 Chinese longan cultivars. Polyphenols (52.9 mg/g dry matter) were obtained from the pericarp of cultivar ‘Wulongling’ fruit by extraction with aqueous acetone. Based on the conventional extraction, Yang et al. (2008d) found a great variation in the contents of water-soluble polysaccharides, water-soluble total saccharides, gallic acid and total phenols in the pericarp of longan among the three cultivars and drying methods tested. The longan pericarp tissues contained a large amount of phenolic compounds and “Shixia” fruit had the highest content (49.4 mg gallic acid equivalents/g dry matter) of total phenols. The contents of total phenolics exhibited a decreasing order for the three

drying methods: lyophilization N microwave radiation N solar radiation. Although gallic acid was not detected in either fresh or lyophilized pericarp tissues, it was found that longan pericarp dried by microwave radiation have a higher content than by solar radiation. Furthermore, Zheng et al. (2009) identified eight polyphenols, i.e., ethyl gallate 1-β-O-galloyl-D-glucopyranose, methyl brevifolin carboxylate, grevifolinand 4-O-α-L-rhamnopyranosyl-ellagic acid, gallic acid, corilagin and ellagic acid present in longan seed. The conventional extraction of polysaccharides from longan pericarp was also investigated using hot water (Yang, Zhao, & Jiang, 2009). It is noted that the conventional extraction method to use different solvents to extract fruit compounds should be considered, due to a large number of longan cultivars available. 2.2. Ultrasonic-assisted extraction The ultrasonic-assisted extraction of oils from chickpea (Lou, Wang, Zhang, & Wang, 2010), saponins from ginseng (Engelberth, Clausen, & Carrier, 2010), polysaccharides (Yang, Jiang, Zhao, Shi, & Wang, 2008) and phenolic compounds such as corilagin from longan pericarp (Prasad et al., 2009; Yang, Zhao, & Jiang, 2008a) were reported. Under the optimal conditions, 85% acidified ethanol with aid of ultrasonication has been demonstrated to obtain a higher extraction yield from longan pericarp, as compared with the conventional extraction (Prasad, Yang, Yi, Zhao, & Jiang, 2009). Likewise, Zhong and Wang (2010) optimized ultrasonic-assisted extraction technology to obtain polysaccharides from dried longan pulp using response surface methodology. These results demonstrate that the ultrasonic-assisted extraction is more effective than the conventional extraction in extracting bioactive compounds from longan pericarp. 2.3. High pressure-assisted extraction The high pressure-assisted extraction (HPE) method, which works under a very high pressure ranging from 100 to 1000 MPa, has been recognized as an environment-friendly technology by the Food and Drug Administration, and is being extensively applied in pharmaceutical, metallurgical and food industries. Various researchers have successfully used the HPE technique for the extraction of bioactive compounds from some fruits such as longan (Prasad, Yang, Yi, et al., 2009; Prasad et al., 2010) and grapes (Corrales et al., 2008). Optimization to obtain high corilagin yield from longan pericarp was investigated under different high pressures (200–500 MPa), times (2.5–30 min), and temperature (30–90 °C) (Prasad, Hao, Shi, et al., 2009). The content of corilagin obtained by HPE (9.65 mg/g dry matter) was significantly higher than that from the ultrasonicassisted extraction (7.91 mg/g dry matter) or conventional extraction (2.35 mg/g dry matter). In addition, the yields of water-soluble polysaccharides, alkali-soluble polysaccharides and cellulose from longan pericarp were comparatively analysed before and after ultrahigh pressure treatment (Yang, Jiang, Wang, Zhao, & Sun, 2009). It was found that a negative relationship was observed between pressure and water-soluble polysaccharide yield. However, ultrahigh pressure treatment significantly (P b 0.05) increased the degrees of hydrolysis of polysaccharides and lignins from longan pericarp. Thus, the efficacy of high pressure to extract different types and yields of bioactive compounds from longan fruit needs to be further investigated due to their different stabilities and diffusion rates. With the recent advances in extraction technologies, bioactive compounds from longan fruit or its by-products can be obtained efficiently. It should be noted that application of high pressureassisted extraction can increase significantly the extraction yield from longan pericarp. Furthermore, fewer impurities of the extract are noticed in the HPE extraction as compared to the conventional extraction (Jiang, Y.M, unpublished data). Thus, the high pressure-

Please cite this article as: Yang, B., et al., Extraction and pharmacological properties of bioactive compounds from longan (Dimocarpus longan Lour.) fruit — A review, Food Research International (2010), doi:10.1016/j.foodres.2010.10.019

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B. Yang et al. / Food Research International xxx (2010) xxx–xxx

3. Nutritional and phytochemical compositions 3.1. Nutrients Table 1 presents the principal nutritional components of longan aril. Furthermore, the different nutritional components for longan fruit may occur across cultivars. The different nutritional components for longan fruit may occur across cultivars. Among these 16 cultivars, ‘Zhuliang’ exhibits the highest single fruit weight (10.3 g) and edible portion (65.9%) (Wen et al., 2010b). The concentrations of total sugars in longan aril increase during ripening, with absolute sugar content varying with stage of maturity and cultivar. The major sugars are sucrose, fructose and glucose (Li, Miao, & Jiang, 2009). Longan aril also contains malic and tartaric acids (Li, Liu, & Wu, 2004). Other organic acids, including oxalic, citric and succinic acids, have also been identified. Malic acid and citric acids are the highest at the intermediate maturity stage, and gradually decrease thereafter. Longan fruit also contains significant amount of amino acids (Wang et al., 2009), especially γ-aminobutyric acid. The content of γ-aminobutyric acid in longan aril ranged from 51 to 180 mg/100 g fresh matter (Zheng et al., 2008). About 28 major volatile compounds from fresh longan aril have been identified to date. The major volatiles include β-ocimene, 3,4dimethyl-2,4,6-octatriene, ethyl acetate, allo-ocimene and 1-ethyl-6ethylidene-cyclohexene (Zhang, Zeng, & Li, 2008; Zhang, Gao, Zhang, Shi, & Xu, 2009). Different extraction methods influence the volatile constituents (Chang, Yu, Chang, & Liu, 2008). Thus, the different volatile profile characteristics for longan fruit may occur across cultivars, environments and cultural practices. 3.2. Phytochemicals Significant amounts of phenolics, fatty acids and proteins exist in longan fruit. Phenolic compounds including gallic acid, corilagin, ellagic acid and their conjugates, (−)-epicatechin, 4-O-methylgallic acid, flavone glycosides, glycosides of quercetin and kaempferol from longan fruit pericarp (Jaitrong, Rattanapanone, & Manthey, 2006; Rangkadilok, Worasuttayangkurn, Bennett, & Satayavivad, 2005; Shi et al., 2008; Sun, Shi, Jiang, Xue, & Wei, 2007), and ethyl gallate 1-β-Ogalloyl-D-glucopyranose, methyl brevifolin carboxylate, grevifolinand 4-O-α-L-rhamnopyranosyl-ellagic acid, gallic acid, corilagin and ellagic acid from longan seed (Zheng et al., 2009) have been identified. Longan aril contains lysophosphatidyl choline, phosphatidyl choline, phosphatidyl inositol, phosphatidyl serine, phosphatidyl ethanolamine, phosphatidate and phosphatidic acid glycerol (Sheng & Wang, 2010). Such phospholipids can be metabolized by a variety of

Table 1 Nutritional composition per 100 g of fresh longan fruit aril. Li et al. (2004) and Wall (2006). Moisture (%) Total carbohydrate Carotene (μg/100 g) Vitamin K (mg/100 g) Reducing sugar (%) Retinol (μg/100 g) Protein (g/100 g) Riboflavin (mg/100 g) Fiber (g/100 g) Ascorbic acid (mg/100 g) Fat (%) Nicotinic acid (mg/100 g) Ash (g/100 g) Thiamine (mg/100 g)

81.4 12.38–22.55 20 196.5 3.85–10.16 3 1.2 0.14 0.4 43.12–163.7 0.1 1.3 0.7 0.01

membrane lipid-related enzymes and may purportedly enhance immune function in human consumers. In addition, longan pericarp contains significant amounts of polysaccharides (Jiang et al., 2009). The polysaccharides are mainly composed of L-arabinofuranose (32.8%), D-glucopyranose (17.6%), D-galactopyranose (33.7%) and D-galacturonic acid (15.9%) (Yang et al., 2009).

4. Pharmacological properties Phenolic compounds present in fruits and vegetables have attracted great attention due to their beneficial effects to human health (Jacob, Hakimuddin, Paliyath, & Fisher, 2008; Lampila, Van Lieshout, Gremmen, & Lahteenmaki, 2009). As longan fruit contains significant amounts of polyphenolic compounds, the longan aril, pericarp or seed extract exhibits great antioxidant, anti-tyrosinase, anti-glycated and anticancer activities (Prasad, Hao, Shi, et al., 2009; Rangkadilok et al., 2007; Soong & Barlow, 2004; Yang et al., 2008c). Furthermore, a combination of longan extract with some commercial drugs can improve treatment efficacy and facilitate the recovery of the patients. In addition, longan pericarp and seed as by-products account for 16–40% of the whole fruit by weight, and, thus, they can potentially be utilized as a readily accessible source of natural antioxidants and a possible pharmaceutical supplement.

4.1. Antioxidant activity There is some direct evidence for the antioxidant potential with phenolic compounds in longan fruit (de Assis et al., 2009; Wen, Li, Mao, & Zhang, 2010a). Guo et al. (2003) compared the antioxidant activities of peel, pulp and seed fractions of longan fruit using the FRAP assay, while Prasad, Yang, Shi, et al. (2010) found that polyphenol-rich longan extract can strongly inhibit linoleic acid oxidation and exhibit a dose-dependent free-radical scavenging activity against DPPH radicals, superoxide anion and hydroxyl radicals (Figs. 1–5). The different total antioxidant capacities were reported in longan arils of various cultivars (Table 2). Among these 16 cultivars, ‘Kusan’ exhibits the lowest FRAP value of 4.19 mmol/L (Yamaguchi, Ariga, Yoshimura, & Nakazawa, 2000). Furthermore, longan polysaccharides showed a good antioxidant activity in vitro (Jiang et al., 2009; Yang, Jiang, Zhao, et al., 2009). However, methylation of polysaccharides from longan pericarp reduced radical scavenging activity (Yang, Zhao, Prasad, Jiang, & Jiang, 2010). In addition, phenolics from longan pericarp have also found to have excellent reducing power (Duan et al., 2007).

DPPH Radical Scavenging activity (%)

assisted extraction technology will exhibit great potential for the extraction of bioactive compounds from longan fruit.

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Fig. 1. Comparison of DPPH radical scavenging activity from longan fruit pericarp after application of HPE, UE and CE. For each treatment, the means in a row followed by different letters were significantly different at the 5% level.

Please cite this article as: Yang, B., et al., Extraction and pharmacological properties of bioactive compounds from longan (Dimocarpus longan Lour.) fruit — A review, Food Research International (2010), doi:10.1016/j.foodres.2010.10.019

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B. Yang et al. / Food Research International xxx (2010) xxx–xxx

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Fig. 2. Comparison of reducing power from longan fruit pericarp after application of HPE, UE and CE. For each treatment, the means in a row followed by different letters were significantly different at the 5% level.

Fig. 4. Comparison of total antioxidant activity from longan fruit pericarp after application of HPE, UE and CE. For each treatment, the means in a row followed by different letters were significantly different at the 5% level.

4.2. Anti-tyrosinase activity

polysaccharides in preventing diabetics and normal aging is worth further evaluation.

Tyrosinase (EC 1.14.18.1) is a multifunctional enzyme that catalyzes both the hydroxylation of monophenols such as tyrosine to o-diphenols and the oxidation of o-diphenols to o-quinones. Meanwhile, the enzyme is widely distributed in organisms and plays an important role in melanin production. Tyrosinase inhibitors may be clinically useful for the treatment of skin cancer and some dermatological disorders associated with melanin hyperpigmentation and are important in cosmetics for whitening and depigmentation after sunburn (Shaheen et al., 2005). Rangkadilok et al. (2007) determined standardized longan fruit extract. Furthermore, Yang et al. (2008a) found that polysaccharides from longan fruit pericarp can strongly inhibit the tyrosinase activity and act as a noncompetitive inhibitor of the enzyme. The inhibition of tyrosinase activity by the major constitutes of longan polysaccharides needs to be investigated further. 4.3. Anti-glycated activity Glycation has been confirmed to have a significant role in diabetic complications and normal aging (Yamaguchi et al., 2000). Polysaccharides from longan pericarp showed a good and stable antiglycated activity (Yang, Zhao, & Jiang, 2009). Ultrasonic-assisted extraction technique can increase the anti-glycated activity of polysaccharides obtained from longan pericarp. The role of longan

4.4. Potential anticancer activity Polyphenol-rich longan seed extract is a free-radical scavenger that possesses known pharmacological properties and is used by humans for therapeutic purposes. Prasad, Hao, Shi, et al. (2009c) reported the anticancer activity of pericarp extract of longan fruit against the HepG2, A549, and SGC7901 cancer cell lines (Table 3). The extract from longan pericarp obtained by the high pressure-assisted extraction showed higher anticancer activity than the conventional extraction. Furthermore, polyphenol-rich longan seed extract also inhibited the proliferation of Colo 320DM, SW480 and HT-29 by blocking cell cycle progression during the DNA synthesis phase and inducing apoptotic death, reduced the expression of cyclin A and cyclin D1, activated caspase 3 and increased the Bax/Bcl-2 ratio (Chung et al., 2010). It was suggested that a polyphenol-rich longan extract can be employed as a potential novel treatment agent for cancer. 5. Other beneficial effects Longan fruit has been used for the traditional Chinese medicine formulation to decrease the neural pain and swelling. Besides the

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Fig. 5. Comparison of lipid peroxidation inhibitory activity from longan fruit pericarp after application of HPE, UE and CE. For each treatment, the means in a row followed by different letters were significantly different at the 5% level.

Please cite this article as: Yang, B., et al., Extraction and pharmacological properties of bioactive compounds from longan (Dimocarpus longan Lour.) fruit — A review, Food Research International (2010), doi:10.1016/j.foodres.2010.10.019

B. Yang et al. / Food Research International xxx (2010) xxx–xxx Table 2 Total antioxidant capacities and total phenolic contents of arils of different longan cultivars. Wen, Xu, et al. (2010b). Cultivar

Antioxidant activity (FRAP value, mmol/L)

Total phenolics (gallic acid equivalents, mg/L juice)

Shixia Qingkebaoyuan Kusan No. 2 Zhuliang Dawuyuan Baihuamu Luosanmu Taobeimu Hualuguangyan Sanlimu Jiruanyan Honghe Shuiyan Dapulong Houkangben Wulonglin

15.82 3.73 4.19 11.18 10.03 10.39 14.04 9.54 15.38 5.50 6.70 13 7.32 10.29 10.83 11.39

629.12 396.65 179.25 401.64 565.82 662.77 558.87 510.44 749.95 80.63 13.02 111.25 51.67 76.71 346.36 370.82

6. Prospects The prospect of increasing production of longan fruit raises expectations for increased utilization opportunities for this crop. Longan fruit contains significant amounts of polyphenolic compounds while phenolic compounds have attracted great attention due to their beneficial effects to human health. Application of ultrasonic-assisted extraction or high pressure-assisted extraction greatly increases the extraction yield from longan pericarp or seed. In recent years, some pharmacological activities such as anti-tyrosinase, anti-glycated, and anticancer activities, and memory-enhancing effects of longan aril, pericarp or seed extract have been found; all of which could make significant contributions to human health. However, possibly due to the presence of allergen (Rank & Li, 2007), some side effects occur with some consumers. The application of thermal processing can eliminate the allergenic potency in longan fruit. Nonetheless, with increasing cultivation area and quantity of longan fruit available in the world, it can be expected that, in the light of health benefits, longan functional foods reflecting the use of these bioactive compounds should be increasingly developed in the future. Table 3 Anticancer activity of longan samples obtained with different extraction methods. Prasad, Hao, Shi, et al. (2009c).

CEL HPEL Cisplatin

Acknowledgements This work was supported by the National Natural Science Foundation of China (Grant Nos. 30928017, U0631004 and 31071638), the CAS/SAFEA international partnership program for creative research teams and the Natural Science Foundation of Guangdong Province (Grant No. 06200670). References

anti-tyrosinase, anti-glycated and anticancer activities, other therapeutic potential of longan fruit have also been found. Park et al. (2010) reported that subchronic administration of aqueous extract of longan fruit could enhance learning and memory, and that its beneficial effects are mediated, in part, by BDNF expression and immature neuronal survival. Currently, the information on other therapeutic uses of longan fruit is very limited, and, thus, other beneficial effects such as antibacterial activity, anti-obesity, and antiviral properties of longan fruit could be evaluated.

Sample

5

Anticancer activity (%) SGC 7901a

HepG2b

A549b

30.58 ± 1.1c 37.6 ± 2.6a 34.26 ± 3.2b

− 0.54 − 0.22 55.34 ± 2.2

NA 11.96 ± 0.80b 49.57 ± 2.1a

NA, no activity; SGC 7901 (human gastric carcinoma); HepG2 (human hepatocellular liver carcinoma); A549 (human lung adenocarcinoma); aConcentration of the sample (50 μg/mL) and bConcentration of the sample (100 μg/mL). CEL, convention-assisted extract of longan and HPEL, high pressure-assisted extract of longan and cisplatin, positive control. For each treatment, the means within a row followed by different letters were significantly different at the 5% level.

Chang, C. H., Yu, T. H., Chang, C. Y., & Liu, Y. C. (2008). Impacts of extraction methods on volatile constituents of longan flower. Journal of Food and Drug Analysis, 16, 46−52. Chung, Y. C., Lin, C. C., Chou, C. C., & Hsu, C. P. (2010). The effect of longan seed polyphenols on colorectal carcinoma cells. European Journal of Clinical Investigation, 40, 713−721. Corrales, M., Toepfl, S., Butz, P., Knorr, D., & Tauscher, B. (2008). Extraction of anthocyanins from grape by-products assisted by ultrasonics, high hydrostatic pressure or pulsed electric fields: A comparison. Innovative Food Science & Emerging Technologies, 9, 85−91. de Assis, S. A., Vellosa, J. C. R., Brunetti, I. L., Khalil, N. M., Leite, K. M. D. C., Martins, A. B. G., & Oliveira, O. M. M. D. (2009). Antioxidant activity, ascorbic acid and total phenol of exotic fruits occurring in Brazil. International Journal of Food Sciences and Nutrition, 60, 439−448. Duan, X. W., You, Y. L., Su, X. G., Qu, H. X., Joyce, D. C., & Jiang, Y. M. (2007). Influence of the nitric, oxide donor, sodium nitroprusside, on lipid peroxidation and antioxidant activity in pericarp tissue of longan fruit. The Journal of Horticultural Science & Biotechnology, 82, 467−473. Engelberth, A. S., Clausen, E. C., & Carrier, D. J. (2010). Comparing extraction method to recover ginseng saponins from American ginseng (I), followed by purification using fast centrifugal partition chromatography with HPLC verification. Separation and Purification Technology, 72, 1−6. Guo, C. J., Yang, J. J., Wei, J. Y., Li, Y. F., Xu, J., & Jiang, Y. G. (2003). Antioxidant activities of peel, pulp and seed fractions of common fruits as determined by FRAP assay. Nutrition Research, 23, 1719−1726. He, N., Wang, Z. Y., Yang, C. X., Lu, Y. H., Sun, D. H., Wang, Y. P., Shao, W. Y., & Li, Q. B. A. (2009). Isolation and identification of polyphenolic compounds in longan pericarp. Separation and Purification Technology, 70, 219−224. Huang, H. B. (1995). Advances in fruit physiology of the arillate fruits of litchi and longan.Annual Review for Horticultural Science, 1, 107−120 (in Chinese). Huang, X., Huang, H. B., & Zeng, L. (2005). Lychee and longan production in China. Acta Horticulturae, 665, 27−36. Jacob, J. K., Hakimuddin, F., Paliyath, G., & Fisher, H. (2008). Antioxidant and antiproliferative activity of polyphenols in novel high-polyphenol grape lines. Food Research International, 41, 419−428. Jaitrong, S., Rattanapanone, N., & Manthey, J. A. (2006). Analysis of the phenolic compounds in longan (Dimocarpus longan Lour.) peel. Proceedings of the Florida State Horticultural Society, 119, 371−375. Jiang, G. X., Jiang, Y. M., Yang, B., Yu, C. Y., Tsao, R., Zhang, H. Y., & Chen, F. (2009). Structural characteristics and antioxidant activities of oligosaccharides from longan fruit pericarp. Journal of Agricultural and Food Chemistry, 57, 9293−9298. Jiang, G. X., Prasad, K. N., Jiang, Y. M., Yang, B., Jia, Y. X., & Sun, J. (2009). Extraction and structural identification of alkali-soluble polysaccharides of longan (Dimocarpus longan Lour.) fruit pericarp. Innovative Food Science & Emerging Technologies, 10, 638−642. Jiang, Y. M., Zhang, Z. Q., Joyce, D. C., & Ketsa, S. (2002). Postharvest biology and handling of longan (Dimocarpus longan Lour.). Postharvest Biology and Technology, 26, 241−252. Lampila, P., Van Lieshout, M., Gremmen, B., & Lahteenmaki, L. (2009). Consumer attitudes towards enhanced flavonoid content in fruit. Food Research International, 42, 122−129. Li, S. F., Liu, X. M., & Wu, J. J. (2004). A review of research and development of longan fruit pulp.Fujian Fruits, 129(2), 12−15 (in Chinese).. Li, J. R., Miao, S. X., & Jiang, Y. M. (2009). Changes in quality attributes of longan juice during storage in relation to effects of thermal processing. Journal of Food Quality, 32, 48−57. Lou, Z., Wang, H., Zhang, M., & Wang, Z. (2010). Improved extraction of oil from chickpea under ultrasound in a dynamic system. Journal of Food Engineering, 98, 13−19. Park, S. J., Park, D. H., Kim, D. H., Lee, S., Yoon, B. H., Jung, W. Y., Lee, K. T., Cheong, J. H., & Ryu, J. H. (2010). The memory-enhancing effects of Euphoria longan fruit extract in mice. Journal of Ethnopharmacology, 128, 160−165. Prasad, K. N., Hao, J., Shi, J., Liu, T., Li, J., Wei, X. Y., Qiu, S. X., Xue, S., & Jiang, Y. M. (2009). Antioxidant and anticancer activities of high pressure-assisted extract of longan (Dimocarpus longan Lour.) fruit pericarp. Innovative Food Science & Emerging Technologies, 10, 413−419. Prasad, K. N., Yang, B., Shi, J., Chun Yi, C., Zhao, M. M., Xue, S., & Jiang, Y. M. (2010). Enhanced antioxidant and antityrosinase activities of longan fruit pericarp by ultrahigh pressure-assisted extraction. Journal of Pharmaceutical and Biomedical Analysis, 51, 471−477. Prasad, K. N., Yang, E., Yi, C., Zhao, M. M., & Jiang, Y. M. (2009). Effects of high pressure extraction on the extraction yield, total phenolic content and antioxidant activity of longan fruit pericarp. Innovative Food Science & Emerging Technologies, 10, 155−159.

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B. Yang et al. / Food Research International xxx (2010) xxx–xxx

Prasad, K. N., Yang, B., Zhao, M. M., Wei, X. Y., Jiang, Y. M., & Chen, F. (2009). High pressure extraction of corilagin from longan (Dimocarpus longan Lour.) fruit pericarp. Separation and Purification Technology, 70, 41−45. Rangkadilok, N., Sitthimonchai, S., Worasuttayangkurn, L., Mahidol, C., Ruchirawat, M., & Satayavivad, J. (2007). Evaluation of free radical scavenging and antityrosinase activities of standardized longan fruit extract. Food and Chemical Toxicology, 45, 328−336. Rangkadilok, N., Worasuttayangkurn, L., Bennett, R. N., & Satayavivad, J. (2005). Identification and quantification of polyphenolic compounds in longan (Euphoria longana Lam.) fruit. Journal of Agricultural and Food Chemistry, 53, 1387−1392. Rank, M. A., & Li, J. T. (2007). Case of food allergy due to longan fruit. Annals of Allergy Asthma & Immunology, 98, A111-A111. Shaheen, F., Ahmad, M., Khan, M. T. H., Jalil, S., Ejaz, A., Sultankhodjaev, M. N., Arfan, M., Choudhary, M. I., & Atta-ur-Rahman (2005). Alkaloids of Aconitum leave and their anti-inflammatory, antioxidant and tyrosinase inhibition activities. Phytochemistry, 66, 935−940. Sheng, K. M., & Wang, H. J. (2010). Advances in research of chemical constituents and pharmacological activities of arillus longan.Chinese Journal of Experimental Traditional Medical Formulae, 16, 236−238 (in Chinese with English abstract). Shi, J. Y., Sun, J., Wei, X. Y., Shi, J., Cheng, G. P., Zhao, M. M., Wang, J. S., Yang, B., & Jiang, Y. M. (2008). Identification of (−)-epicatechin as the direct substrate for polyphenol oxidase from longan fruit pericarp. LWT — Food Science and Technology, 41, 1742−1747. Soong, Y. Y., & Barlow, P. J. (2004). Antioxidant activity and phenolic content of selected fruit seeds. Food Chemistry, 88, 411−417. Sun, J., Shi, J., Jiang, Y. M., Xue, S. J., & Wei, X. Y. (2007). Identification of two polyphenolic compounds with antioxidant activities in longan pericarp tissues. Journal of Agricultural and Food Chemistry, 55, 5864−5868. Tindall, H. D. (1994). Sapindaceous fruits: Botany and horticulture. Horticultural Review, 16, 143−196. Wall, M. M. (2006). Ascorbic acid and mineral composition of longan (Dimocarpus longan), lychee (Litchi chinensis) and rambutan (Nephelium lappaceum) cultivars grown in Hawaii. Journal of Food Composition and Analysis, 19, 655−663. Wang, H. Q., Ke, L. J., Xiang, L. W., Gao, G. Z., Rao, P. F., & Zhou, J. W. (2009). Analysis of amino acids in arillus longan during heating process.Amino Acids & Biotic Resources, 31(2), 14−16 (in Chinese with English abstract). Wen, L. J., Li, Y. J., Mao, H. J., & Zhang, Y. C. (2010). Nutrients and antioxidant activity of longan seeds.Food Science, 31(1), 243−246 (in Chinese with English abstract). Wen, J., Xu, Y. J., Xaio, G. S., Li, J. G., Liao, S. T., Wu, J. J., Li, S. F., & Tang, D. B. (2010). Comparative studies on processing characteristics of different longan cultivars.Food Science, 31(1), 71−75 (in Chinese with English abstract). Yamaguchi, F., Ariga, T., Yoshimura, Y., & Nakazawa, H. (2000). Antioxidative and antiglycation activity of garcinol from Garcinia indica fruit rind. Journal of Agricultural and Food Chemistry, 48, 180−185.

Yang, B., Jiang, Y. M., Wang, R., Zhao, M. M., & Sun, J. (2009). Ultra-high pressure treatment effects on polysaccharides and lignins of longan fruit pericarp. Food Chemistry, 112, 428−431. Yang, B., Jiang, Y. M., Zhao, M. M., Chen, F., Wang, R., Chen, Y. L., & Zhang, D. D. (2009). Structural characterisation of polysaccharides purified from longan (Dimocarpus longan Lour.) fruit pericarp. Food Chemistry, 115, 609−614. Yang, B., Jiang, Y. M., Zhao, M. M., Shi, J., & Wang, L. Z. (2008a). Effects of ultrasonic extraction on the physical and chemical properties of polysaccharides from longan fruit pericarp. Polymer Degradation and Stability, 93, 268−272. Yang, B., Zhao, M. M., & Jiang, Y. M. (2008b). Optimization of tyrosinase inhibition activity of ultrasonic-extracted polysaccharides from longan fruit pericarp. Food Chemistry, 110, 294−300. Yang, B., Zhao, M. M., & Jiang, Y. M. (2009). Anti-glycated activity of polysaccharides of longan (Dimocarpus longan Lour.) fruit pericarp treated by ultrasonic wave. Food Chemistry, 114, 629−633. Yang, B., Zhao, M. M., Prasad, K. N., Jiang, G. X., & Jiang, Y. M. (2010). Effect of methylation on the structure and radical scavenging activity of polysaccharides from longan (Dimocarpus longan Lour.) fruit pericarp. Food Chemistry, 118, 364−368. Yang, B., Zhao, M. M., Shi, J., Cheng, G. P., Ruenroengklin, N., & Jiang, Y. M. (2008c). Variations in water-soluble saccharides and phenols in longan fruit pericarp after drying. Journal of Food Process Engineering, 31, 66−77. Yang, B., Zhao, M. M., Shi, J., Yang, N., & Jiang, Y. M. (2008d). Effect of ultrasonic treatment on the recovery and DPPH radical scavenging activity of polysaccharides from longan fruit pericarp. Food Chemistry, 106, 685−690. Zhang, Y., Gao, B., Zhang, M. W., Shi, J., & Xu, Y. J. (2009). Headspace solid-phase microextraction–gas chromatography–mass spectrometry analysis of the volatile components of longan (Dimocarpus longan Lour.). European Food Research and Technology, 229, 457−465. Zhang, Z. M., Zeng, D. D., & Li, G. K. (2008). Study of the volatile profile characteristics of longan during storage by a combination sampling method coupled with GC/MS. Journal of the Science of Food and Agriculture, 88, 1035−1042. Zheng, S. Q., Jiang, F., Huang, A. P., Gao, H. Y., Deng, C. J., Chen, X. M., & Zheng, J. G. (2008). Evaluating of γ-aminobutyric acid in different genotypes from longan (Dimocarpus longan Lour.).Fujian Fruits, 146(3), 23−27 (in Chinese with English abstract). Zheng, G. M., Xu, L. X., Wu, P., Xie, H. H., Jiang, Y. M., Chen, F., & Wei, X. Y. (2009). Polyphenols from longan seeds and their radical-scavenging activity. Food Chemistry, 116, 433−436. Zhong, K., & Wang, Q. (2010). Optimization of ultrasonic extraction of polysaccharides from dried longan pulp using response surface methodology. Carbohydrate Polymers, 80, 19−25.

Please cite this article as: Yang, B., et al., Extraction and pharmacological properties of bioactive compounds from longan (Dimocarpus longan Lour.) fruit — A review, Food Research International (2010), doi:10.1016/j.foodres.2010.10.019