HPTLC quantitative estimation of quercetin in ethanol extracts of P. betle and C. dactylon leaves, the roots of P. zeylanica and R. cordifolia, the rhizomes of S. china, the stem of T. cordifolia, N. sativa seeds, and polyherbal formulation

Quercetin, a powerful antioxidant flavonoid, is found in various plant extracts, including fruits, vegetables, and even plant waste, with onions, apples, berries, and green tea being notable sources. The current study aims to quantify the quercetin from ethanol extracts of Piper betle and Cynodon dactylon leaves, the roots of Plumbago zeylanica and Rubia cordifolia, the rhizomes of Smilax china, the stem of Tinospora cordifolia, Nigella sativa seeds and a polyherbal formulation. The polyherbal formulation was prepared from the 50% ethanol extracts of P. betle and C. dactylon leaves, the roots of P. zeylanica and R. cordifolia, the rhizomes of S. china, the stem of T. cordifolia, and N. sativa seeds for the treatment of atopic conditions. All these herbal plants were collected and authenticated. Dried herbs were macerated with 50% ethanol, filtered, concentrated, and freeze-dried using a lyophilizer. The polyherbal formulation is prepared by adding one equal part powder from each herb. The HPTLC quantification was carried out to quantify the quercetin in individual ethanol extracts of and the PHF. Chromatographic separation was performed on precoated HPTLC plates using silica gel 60F254 for quantification. A simple, rapid, and accurate HPTLC technique was used for measuring quercetin using toluene: ethyl acetate: formic acid (10.9:8.7:0.4), in compliance with ICH guidelines. The plates were scanned at wavelengths of 254 nm using a TLC scanner IV. The HPTLC test showed that quercetin was present in ethanol extracts of P. betle and C. dactylon, P. zeylanica, R. cordifolia, S. china, T. cordifolia, N. sativa and PHF.