The aim of the study was to evaluate the phytochemical components and antioxidant potential of methanolic and hydrophilic extracts isolated from in vivo and in vitro cultures of onion varieties of Bellary and CO 3. Phytochemical components like total flavonoids, phenolics, ascorbic acid and anthocyanins were analyzed. The antioxidant activities were examined by DPPH and FRAP methods. The results indicated that the both the methanolic extracts exhibited radical scavenging activity. The DPPH scavenging activity in Bellary and CO 3 onion varieties ranged from 6.5% - 11.8% whereas FRAP values ranged from 0.9 - 3.3 μM/100 μg FW. The total anthocyanins ranged from 9.9 - 29.9 mg/kg, vitamin-C 48.6 - 78.6 mg/kg, total phenolics and flavonoids content was 15.7 - 34.7 mg/g GAE and 0.65 - 1.17 mg/g respectively. Substantial amounts of anthocyanins, phenols, flavonoids and ascorbic acid were noticed in both the varieties. Our study revealed that the possible mechanism of the biological activities in onion could be due to the free radical scavenging and antioxidant activities. The polyphenols present in the onion bulbs may be responsible for these beneficial activities. This study clearly demonstrated that both the onion varieties possess very characteristic antioxidant potential that will help us in keeping good health.
KeywordsOnionAntioxidantsPhenolicsFlavonoids
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