Food Chemistry, Nutrition and Safety

Biography

Biography: Jirapast Sichaem

Abstract

Averrhoa bilimbi L. (Oxalidaceae), commonly known as “Ta Ling Pling” in Thai, is a juicy tropical fruit grown in Thailand and throughout Southeast Asia with commercial value. There are mainly two types of fruit in terms of taste, sweet and sour. It is primarily used as a folk medicine for treating diabetes mellitus, hypertension, and as an antimicrobial agent. A. bilimbi extracts exhibit a wide range of pharmacological activities, including antidiabetic, antihypertensive, antithrombotic, hypolipidemic, hepatoprotective, cytotoxic, antimicrobial, wound healing, anthelmintic, and antioxidant properties. Previous chemical investigations on A. bilimbi reported the isolation of flavonoid glycosides, dihydrochalcone glycosides, terpenoids, peptides, and phenylpropanoids. In this phytochemical study, we investigated the fruits and leaves of Thai A. bilimbi. As a result, eight compounds were isolated from the fruits, including β-sitosterol (1), lupeol (2), zeorin (3), phyllanthin (4), catechin (5), isorhamnetin-3-O-rutinoside (6), horridin (7), and rutin (8). From the leaves, six compounds were isolated, including β-amyrin heptadecanoate (9), β-amyrin (10), β-sitosterol (1), β-sitosterol-D-glucoside (11), β-sitosteryl oleate (12), and α-tocopherol (13). Among all isolated compounds, compound 1 is a new triterpenoid. The structures of all isolated compounds were fully characterized using spectroscopic data (NMR and HRESIMS) and comparison with previous literature. The new compound (1) was selected to evaluate its α-glucosidase inhibitory activity and demonstrated effective α-glucosidase inhibition, with an IC₅₀ of 17.5 μM, outperforming the standard acarbose (IC₅₀ 82.0 μM).