RESUMO
Aronia, blueberry, Korean raspberry, blackberry, mulberry, and red raspberry fruits cultivated in Korea were evaluated for total phenol content (TPC), total flavonoid content (TFC), total anthocyanin, and ascorbic acid content. All berries were assayed for antioxidant activities determined as 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity, 2,2'-azino-bis(3-ethylbenzothiazoline)-6 sulphonic acid free radical scavenging activity, and ferric reducing antioxidant power. Individual phenolic compounds in aronia were also identified using high-performance liquid chromatography/quadrupole-time of flight mass spectrometry. TPC, TFC, total anthocyanin, and ascorbic acid contents of the fruit samples ranged from 17.05 to 135.55 mg of gallic acid equivalent/g dry weight (dw), 1.0 to 8.59 mg of rutin equivalent/g dw, 2.55 to 24.43 mg of cyanidin-3-O-glucoside equivalent/g dw, and 3.14 to 19.45 mg of ascorbic acid equivalent/g dw, respec-tively. Aronia and Korean raspberry showed the highest TPC, TFC, and total anthocyanin while red raspberry had the high-est ascorbic acid content. Antioxidant activities showed positive correlations to phenolic and anthocyanin contents suggesting antioxidant activity of berry samples is due to these compounds. Aronia had the highest antioxidant value among fruits.
RESUMO
Essential oil obtained from Maclura triscuspidata fruit has been reported to have functional properties. This study aimed at determining chemical compositions and antioxidant activities of steam-distilled essential oil (SDEO) and glycosidically bound aglycone fraction (GBAF) isolated from fully ripe M. triscuspidata fruit. SDEO was isolated by simultaneous steam distillation and extraction (SDE). GBAF was prepared by Amberlite XAD-2 adsorption of methanol extract, followed by methanol elution and enzymatic hydrolysis. Both fractions were analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 76 constituents were identified from both oils. Apart from fatty acids and their esters, the SDEO contained p-cresol in the highest concentration (383.5 ± 17.7), followed by δ-cadinene (147.7 ± 7.7), ß-caryophyllene (145.7 ± 10.5), ß-ionone (141.0 ± 4.5), n-nonanal (140.3 ± 20.5), theaspirane A (121.3 ± 4.5) and theaspirane B (99.67 ± 9.05 µg/g). Thirteen carotenoid-derived compounds identified in the SDEO are being isolated from M. triscuspidata fruit for the first time. Out of the 22 components identified in GBAF, 14 were present only in the glycosidically bound volatiles. Antioxidant activity of the GBAF was higher than that of SDEO. These results suggest that glycosidically bound volatiles of M. triscuspidata fruit have a good potential as natural antioxidants.