Flavonoids from the fruits of Phyllanthus acidus (L.) Skeels with anti-α-glucosidase activity

Abstract

Eleven flavonoids including one new flavonol glycoside, quercetin-3-O-(2-α-L-rhamnopyranosyl)-β-D-glucuronopyranosyl methyl ester (1), were isolated for the first time from the fruits of Phyllanthus acidus (L.) Skeels (Phyllanthaceae). Their structures were determined by extensive spectroscopic data. The known flavonoids, quercetin-3-O-β-D-glucuronide methyl ester (3), quercetin-3-O-(2''-α-L-rhamnopyranosyl-6''-O-α-L-rhamno pyranosyl)-β-D-glucopyranoside (5), myricetin (9), and 6-methoxy-naringenin (11) were isolated for the first time from the genus Phyllanthus. Flavonoids 4, 6 and 9 (IC₅₀ = 6.01, 6.32, and 7.84 μM, respectively) showed stronger α-glucosidase inhibitory activities than the positive control, acarbose (IC₅₀ = 306.45 μM). The fruits of P. acidus might be further developed as an anti-diabetic food supplement.

Graphical Abstract

Keywords:

• Phyllanthaceae
• Phyllanthus acidus (L.) Skeels
• flavonoids
• anti-α-glucosidase activity

Disclosure statement

No potential conflict of interest was reported by the authors.

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Additional information

Funding

This work was supported by the National Natural Science Foundation of China (82074124) and the Key Project of Basic Research Plan of Yunnan Province, China (202001AS070017). We are grateful to the staffs of the analytical and bioactivity screening group at the State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, for measuring the spectroscopic data and antidiabetic activity.