Park et al.: Journal of aoaC InternatIonal Vol. 95, no. 6, 2012 1725 Analytical Determination of Bioactive Compounds as an Indication of Fruit Quality Y ong Seo Park Mokpo National University, Department of Horticultural Science, Muan, Jeonnam, South Korea Buk-gu Heo Naju Foundation of Natural Dyeing Cultural Institute, Naju, South Korea kYung-Sik Ham, Seong-gook kang, and Y ang-kYun Park Mokpo National University, Department of Food Engineering, Muan, Jeonnam, South Korea alina nemirovSki, Zeev T aSHma, and SHela gorinSTein 1 The Hebrew University, Hadassah Medical School, The Institute for Drug Research, School of Pharmacy, Jerusalem 91120, Israel Hanna leonTowicZ and maria leonTowicZ Warsaw University of Life Sciences (SGGW), Faculty of Veterinary Medicine, Department of Physiological Sciences, Warsaw, Poland Received March 26, 2012. Accepted by SG April 30, 2012. 1 Corresponding author’s e-mail: gorin@cc.huji.ac.il DOI: 10.5740/jaoacint.12-130 FOOD COMPOSITION AND ADDITIVES The aim of this investigation was to determine the bioactive compounds in kiwifruit as an indication of quality after extraction using methanol and ethyl acetate. Using FTIR and three-dimensional fuorescence spectroscopy and electrospray ionization/MS, the contents of polyphenols, favonoids, favanols, and tannins, and the level of the antioxidant activity by 2, 2-azino-bis (3-ethyl- benzothiazoline-6-sulfonic acid) diammonium salt, 1, 1-diphenyl-2-picrylhydrazyl, ferric-reducing/ antioxidant power, and cupric reducing antioxidant capacity assays were determined and compared. It was found that the methanol extracts of kiwifruit showed signifcantly higher amounts of bioactive compounds and antioxidant activities than the ethyl acetate extracts. The cultivar Bidan, in comparison with the classic Hayward, showed signifcantly higher bioactivity. For the frst time, Bidan organic kiwifruit was analyzed for its antioxidant activities and compared with the widely consumed Hayward organic based on its bioactive compounds and fuorescence properties. Relatively high content of bioactive compounds and positive antioxidant and antiproliferative properties of kiwifruit determined by the advanced analytical methods justify its use as a source of valuable antioxidants. The methods used are applicable for bioactivity determination, in general, for any food products. C onsumption of fruit and vegetables has the potential to reduce nontransmissible diseases, such as cardiovascular diseases and cancer, which are major public health concerns (1–3). Many epidemiologic studies have shown that a diet rich in apples can reduce cardiovascular events (myocardial infarction and stroke) and some type of cancers (1). Increased consumption of vegetables, particularly cruciferous ones, and fruits promote cardiovascular health and overall longevity (2). Among the widely consumed fruits is kiwifruit, which is popular in the United States and Europe (4, 5). Kiwifruits have many cultivars; the best-known is Hayward. Bidan is less spread and consumed than Hayward. Both belong to the Actinidia deliciosa species that is known for good taste (6–8). However, the good taste of this fruit is not the only positive property: Duttaroy and Jøorgensen, in a clinical trial of human volunteers, showed that kiwifruit is effective in the prevention of coronary atherosclerosis (9). It was found that consumption of two or three kiwifruits/day lowers the blood triglyceride level by 15% and reduces platelet aggregation response by 18% compared with controls (P < 0.05). There is growing interest concerning organically versus conventionally grown fruits and vegetables. The differences in the bioactivity between kiwifruit cultivars grown in conventional and organic conditions have been less studied (10). Therefore, it was decided to compare their bioactivity using two different solvents (methanol and ethyl acetate). Not all investigators used complementary assays for determination of the antioxidant activity (11). In order to obtain reliable data about the antioxidant activity of the studied samples, four generally accepted assays were used: 2, 2-azino- bis (3-ethyl-benzothiazoline-6-sulfonic acid) diammonium salt (ABTS; 12); 1, 1-diphenyl-2-picrylhydrazyl (DPPH; 13); ferric- reducing/antioxidant power (FRAP; 13); and cupric reducing antioxidant capacity (CUPRAC; 14). As far as we know, results of such investigations have not been published. Experimental Chemicals 6-Hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; catechin; quercetin; Tris, tris (hydroxymethy1) aminomethane; bovine serum albumin, ABTS, DPPH, Folin-Ciocalteu reagent; lanthanum (III) chloride heptahydrate, FeCl 3 ∙ 6H 2 O, CuCl 2 ∙ 2H 2 O, 2,9-dimethyl-1,10-phenanthroline (neocuproine); and bovine serum albumin (BSA) were purchased from Sigma Chemical Co., St. Louis, MO. 2,4,6-Tripyridyl-s-triazine (TPTZ) was purchased from Fluka Chemie (Buchs, Switzerland). All reagents were of analytical grade. Deionized and distilled water (Bio-Lab Ltd, Jerusalem, Israel) was used throughout. Downloaded from https://academic.oup.com/jaoac/article/95/6/1725/5655305 by guest on 04 July 2023