ANTIOXIDANTS FROM SELECTED INDIGENOUS PLANTS POSSESSING CYCLOTIDES

摘要

Antioxidants present in plants like secondary metabolites and peptides are gaining much interest while addressing the issues of oxidative damages to human and agriculture. The present study focused on evaluating the antioxidant potential of selected plants of indigenous sources including Viola odorata, V. tricolor, V. hybrid, pansy super hybrid Fl, Petunia mix, Clitoria ternatea, Panicum vigatum, P. laxam, P. maximum and Hamelia patens, families gaining medicinal interests due to cyclotides reported from them. Phenolics and crude protein contents were specifically extracted using phosphate buffer saline (PBS) and protein extraction buffer (PEB), respectively. Analysis showed among leaves, Petunia contains maximum proteins 3.21 mg/g of plant powder in PEB extract and Clitoria among seeds contains 1.95 mg/g in PEB (0.96 mg/g in PBS). Maximum phenolics and flavonoids were observed as 22.13 mg/g of GAE in V. hybrid (PBS) and 36.99 mg/g of catechin, in P. vigatum leaves (PBS), respectively. The lowest phenolics exists in P. vigatum 8.06 mg/g while least flavonoids in Hamelia seeds 3.91 mg/g. Maximum Fe~(3+) reducing powers of 16.17 and 11.97% were observed in PBS extract of Petunia leaves and Hamelia seeds extract in PEB. Clitoria leaves similar to Petunia among highest in proteins showed 9.8% reducing power which decreased on Proteinase-K treatment. Antioxidant behaviour of proteins was observed when PEB extracts of Petunia were treated with proteinases with maximum loss of DPPH radical scavenging activity from 70.31 to 32.56% (i.e. 38%). Extracts of selected plants showed antioxidant behaviour due to phenolics, flavonoids and protein contents. Results were statistically analysed for their significance and comparison.