Research on HPLC-Based Flavonoid Fingerprinting and Quantitative Analysis of Bauhinia purpurea Linn. Flower Extract

The idea of health consciousness is rapidly gaining popularity, leading to increased reliance on herbal remedies with fewer adverse effects compared to modern medicines. Bauhinia purpurea L. is a prominent medicinal species traditionally utilized for its antidiarrheal, anticancer, and thyroid gland-stimulating properties. The flowers of this plant are particularly rich in phytoconstituents, making them a valuable source for pharmaceutical applications. This study aimed to identify and quantify the flavonoids, specifically quercetin, present in the ethanolic flower extract of B. purpurea using Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC). The extraction was performed using Soxhlet, maceration, and sonication methods, with the Soxhlet extraction yielding 23.07% crude extract. Preliminary phytochemical screening confirmed the presence of flavonoids and phenolics. Thin Layer Chromatography (TLC) utilizing a mobile phase of toluene : chloroform : ethyl acetate (2:2:0.5) successfully separated quercetin, demonstrating an R_f value between 0.47 and 0.60. Further, an efficient RP-HPLC method was developed using a C18 column and a mobile phase of methanol : acetonitrile (7:3) with 0.1% formic acid. The standard quercetin exhibited a retention time (R_t) of 5.52 to 5.62 min, while the sample extract confirmed its presence with a matching R_t of 5.68 to 5.70 min. The study confirms that B. purpurea flowers are a promising natural source of bioactive flavonoids, supporting their potential therapeutic and nutraceutical use.