Manasa Machavarapu, Manoj Kumar Sindiri and Meena Vangalapati
Allium cepa is the most common and richest natural source of flavonoids. In this study the extraction of flavonoids quercetin and rutin and the total phenolic compounds were carried out. Optimization of physico-chemical parameters namely effects of different solvents, different solvent percentages, soaking time, different amounts of sample (Skin of Allium cepa) and different pH were studied. For the extraction of quercetin, the optimum results were 80% (v/v), 1d, 1% (w/v) and pH 5.5 respectively. The highest quercetin and rutin concentration for optimized conditions were 185.309 μg/L and 124.69 μg/L respectively and it was found to be 19.412 mg/L for total phenolic content