PHYTOCHEMICAL AND ANTIOXIDANT CHARACTERIZATION OF THINNED IMMATURE CITRUS UNSHIU FRUITS
Objective: We aimed to evaluate the characterization of thinned immature Citrus unshiu fruits with regard to their phytochemical profile and antioxidant capacity.
Methods: Determination of total phenolic, flavonoid, and carotenoid and ascorbic acid contents was done by UV-Visible spectrophotometry, whereas UPLC-mass detection was used for the analysis of individual flavanone (naringin, hesperidin, hesperetin, neohesperedine and narirutin) and flavonol (rutin). In addition, free radicals (DPPH, O2-, H2O2 and NO) scavenging assays were used to determine the antioxidant capacity.
Results: Naringin, hesperidine, neohesperedine and narirutin were the main flavanones in all thinned immature Citrus unshiu fruits. The contents of total phenolic, flavonoid and carotenoid were more prevalent in immature fruits than the level found in mature fruits. All thinned immature Citrus unshiu fruits possess an evident antioxidant capacity. The immature Citrus extract concentrations providing 50% inhibition (IC50) for free radicals; 1.2-1.49 mg/ml for DPPH, 1.03-1.46 mg/ml for superoxide, 1.95-3.43 mg/ml for hydrogen peroxide and 1.64-3.45 mg/ml for nitric oxide was lower than those of mature Citrus extracts.
Conclusion: Thinned immature Citrus unshiu fruits could be an economic and readily accessible source of natural antioxidants and as a possible food and pharmaceutical supplement.
2. Molina EG, DomÃnguez RP, Moreno DA, Garcia CG. Natural bioactive compounds of Citrus limon for food and health. J Pharm Biomed Anal 2010;51:327-45.
3. Yang EJ, Kim SS, Oh JS, Baik JS, Lee NH, Hyun CG. Essential oil of citrus fruit waste attenuates LPS-induced nitric oxide production and inhibits the growth of skin pathogens. Int J Agric Biol 2009;11:791-4.
4. Barreca D, Bellocco E, Caristi C, Leuzzi U, Gattuso G. Flavonoid composition and antioxidant activity of juices from Chinotto (Citrus x myrtifolia Raf.) fruits at different ripening stages. J Agric Food Chem 2010;58:3031-6.
5. Inoue T, Tsubaki S, Ogawa K, Onishi K, Azuma J. Isolation of hesperidin from peels of thinned Citrus unshiu fruits by microwave-assisted extraction. Food Chem 2010;12:542-7.
6. Im SJ, Kim JH, Kim MY. Evaluation of bioactive components and antioxidant and anticancer properties of Citrus wastes generated during bioethanol production. Nat Prod Commum 2014;9:483-6.
7. Rainha N, Lima E, Baptista J, Rodrigues C. Antioxidant properties, total phenolic, total carotenoid and chlorophyll content of anatomical parts of Hypericum foliosum. J Med Plants Res 2011;5:1930-40.
8. Klein BP, Perry AK. Ascorbic acid and vitamin an activity in selected vegetables from different geographical areas of the United States. J Food Sci 1982;47:941-5.
9. Kim JH, Kim MY. The potential use of Citrus juice waste as sources of natural phenolic antioxidants. J Appl Pharm Sci 2016;6:202-5.
10. RiceEvans CA, Miller NJ. Antioxidant activities of flavonoids as bioactive components of food. Biochem Soc Trans 1996;24:790-5.
11. Aharmas S, Saxena J. Phytochemical screening and quantitative estimation of total phenolic content and total flavonoid content of grains of Paspalum scrobiculatum. Asian J Pharm Clin Res 2016;9:73-6.
12. Sikora E, CieÅ›lik E, Topolska K. The sources of natural antioxidants. Acta Sci Pol Technol Aliment 2008;7:5-17.
13. Wang YC, Chuang YC, Hsu HW. The flavonoid, carotenoid and pectin content in peels of Citrus cultivated in Taiwan. Food Chem 2008;106:277-84.
14. Benavente Garcia O, Castillo J, Marin FR, Ortuno A, Del Rio JA. Uses and properties of Citrus flavonoids. J Agric Food Chem 1997;45:4505-15.
15. Gattuso G, Barreca D, Gargiulli C, Leuzzi U, Caristi C. Flavonoid composition of Citrus juices. Molecules 2007;12:1641-73.
16. Choi SY, Ko HC, Ko SY, Hwang JH, Park JG, Kang SH, et al. Correlation between flavonoid content and the NO production inhibitory activity of peel extracts from various Citrus fruits. Biol Pharm Bull 2007;30:772-8.
17. Ye XQ, Chen JC, Liu DH, Jiang P, Shi J, Xue S. Identiï¬cation of bioactive composition and antioxidant activity in young mandarin fruits. Food Chem 2011;124:1561-6.
18. Nogata Y, Sakamoto K, Shiratsuchi H, Ishii T, Yano M, Ohta H. Flavonoid composition of fruit tissues of Citrus species. Biosci Biotechnol Biochem 2006;70:178-92.
19. Heim KE, Tagliaferro AR, Bobilya DJ. Flavonoid antioxidants: chemistry, metabolism and structure-activity relationship. J Nutr Biochem 2002;13:572-84.
20. Parr A, Bolwell GP. Phenols in the plant and in man: The potential for possible nutritional enhancement of the diet by modifying the phenols content or profile. J Sci Food Agric 2000;80:985-1012.
21. Archana B, Dasgupta N, De B. In vitro study of antioxidant activity of Syzygium cumini fruit. Food Chem 2005;90:727-33.
22. Atina RC, Irda F, Komar R. Comparison of five antioxidant assays for estimating antioxidant capacity from three Solanum SP. extracts. Asian J Pharm Clin Res 2016;9:123-8.
23. Huang D, Ou B, Prior RL. The chemistry behind antioxidant capacity assays. J Agric Food Chem 2005;53:1841-56.