Antidiabetic and antimicrobial flavonoids from the twigs and roots of Erythrina subumbrans (Hassk.) Merr.
Piyaporn Phukhatmuen,
Pornphimol Meesakul,
Virayu Suthiphasilp,
Rawiwan Charoensup,
Tharakorn Maneerat,
Sarot Cheenpracha,
Thunwadee Limtharakul,
Stephen G. Pyne,
Surat Laphookhieo
Affiliations
Piyaporn Phukhatmuen
Center of Chemical Innovation for Sustainability (CIS) and School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand
Pornphimol Meesakul
Center of Chemical Innovation for Sustainability (CIS) and School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand
Virayu Suthiphasilp
Center of Chemical Innovation for Sustainability (CIS) and School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand
Rawiwan Charoensup
School of Integrative Medicine, Mae Fah Luang University, Chiang Rai, 57100, Thailand; Medicinal Plant Innovation Center of Mae Fah Luang University, Chiang Rai, 57100, Thailand
Tharakorn Maneerat
Center of Chemical Innovation for Sustainability (CIS) and School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand; Medicinal Plant Innovation Center of Mae Fah Luang University, Chiang Rai, 57100, Thailand
Sarot Cheenpracha
School of Science, University of Phayao, Phayao, 56000, Thailand
Thunwadee Limtharakul
Department of Chemistry, Faculty of Science and Research Center on Chemistry for Development of Health Promoting Products from Northern Resources, Chiang Mai University, Chiang Mai, 50200, Thailand
Stephen G. Pyne
School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales, 2522, Australia
Surat Laphookhieo
Center of Chemical Innovation for Sustainability (CIS) and School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand; Medicinal Plant Innovation Center of Mae Fah Luang University, Chiang Rai, 57100, Thailand; Corresponding author.
The phytochemical investigation of the twig and root extracts of Erythrina subumbrans (Hassk.) Merr. (Fabaceae) resulted in the isolation and identification of a new pterocarpan, erythrinocarpan (1), along with 27 known compounds (2–28). All isolated compounds were evaluated for their antidiabetic, antimicrobial, and anti-inflammatory properties. Compounds 3, 8, 9, and 22 had α-glucosidase inhibitory activity with IC50 values of 13.4 ± 0.05, 24.5 ± 0.13, 29.0 ± 0.05, and 12.8 ± 0.14 μM, respectively, while compound 2 inhibited α-amylase activity with an IC50 value of 67.6 ± 1.12 μM. Compounds 22 and 24 inhibited glycation activity with the IC50 values of 36.9 ± 0.62 and 40.5 ± 0.37 μM, respectively. From cell-based assays, compound 27 showed the highest ability to induce glucose consumption (IC50 29.1 ± 0.86 μM) and glucose uptake (2.8-fold), and to inhibit nitric oxide (NO) production (IC50 52.5 ± 0.56 μM) without cell toxicity. Furthermore, compound 9 showed antimicrobial activities against Gram-positive bacteria and fungi with MIC values ranging from 2–4 μg/mL.
