Determination of anti-oxidant capacity and content of phenols, phenolic acids, and flavonols in Indian and European gooseberry

Abstract

AbstractPhenolic acids and derivatives of quercetin in Indian (amla) and European gooseberry were determined by high-performance liquid chromatography with diode array detector. The calibration curves were constructed using phenolic compounds standards (the coefficient of determination (R 2) was 0.9990–0.9997 for phenolic acids and 0.9989–0.9994 for flavonols, respectively). The lowest detection limit was 0.28 mg L−1 and 0.35 mg L−1 for hyperoside and gallic acid, respectively, whereas the highest was 1.80 mg L−1 and 7.98 mg L−1 for quercetin and chlorogenic acid, respectively. The quantification limits calculated were 0.85–24.04 mg L−1 for hyperoside and chlorogenic acid, respectively. The predominant phenolic acid in amla and gooseberry is gallic acid: (5.37 ± 0.04) mg per 100 g of dry mass (d.m.) and (3.21 ± 0.03) mg per 100 g of d.m., respectively. The next one was caffeic acid, 0.65–1.22 mg per 100 g of d.m., followed by p-coumaric acid, 0.84–1.17 mg per 100 g of d.m. Out of the flavonols, rutin is predominant: (3.11 ± 0.13) mg per 100 g of d.m. and (2.12 ± 0.03) mg per 100 g of d.m., respectively. Anti-oxidant activity was also determined.