HPLC-Based Quantitative Phytochemical Analysis of Aqueous and Ethanol Leaf Extracts of Psidium guajava L.

Abstract

Psidium guajava (guava) leaves are widely used in traditional medicine, but comparative evidence on solvent-dependent differences in their phytochemical composition remains limited. This study compared the quantitative phytochemical profiles of aqueous and ethanol extracts of P. guajava leaves. Leaves collected from Wukari Local Government Area, Taraba State, Nigeria, were shade-dried, powdered, and separately macerated in 95% ethanol and distilled water for 72 hours. Individual bioactive compounds were analysed using high-performance liquid chromatography (HPLC) with diode-array detection. Both extracts tested positive for flavonoids, tannins, saponins, alkaloids, terpenoids, phenolics, and steroids. HPLC analysis identified quercetin, chlorogenic acid, vanillic acid, and caffeine in the ethanol extract, with caffeine constituting the most abundant identified compound at 9.4% of the total quantified content. The aqueous extract contained ellagic acid, luteolin, chrysin, pelargonidin, campesterol, stigmasterol, and vanillic acid, with ellagic acid predominating at 48.8% of the total quantified content. The ethanol extract exhibited higher quercetin and total phenolic contents, whereas the aqueous extract showed higher tannin and saponin contents. These findings indicate distinct solvent-dependent phytochemical profiles and provide comparative baseline data to guide extract selection for subsequent pharmacological evaluation, including investigations of potential antidiarrhoeal, haematoprotective, nephroprotective, and hepatoprotective applications.