Potential α-Glucosidase Inhibitors from the Deep-Sea Sediment-Derived Fungus Aspergillus insulicola

Abstract

Three new phenolic compounds, epicocconigrones C–D (1–2) and flavimycin C (3), together with six known phenolic compounds: epicocconigrone A (4); 2-(10-formyl-11,13-dihydroxy-12-methoxy-14-methyl)-6,7-dihydroxy-5-methyl-4-benzofurancarboxaldehyde (5); epicoccolide B (6); eleganketal A (7); 1,3-dihydro-5-methoxy-7-methylisobenzofuran (8); and 2,3,4-trihydroxy-6-(hydroxymethyl)-5-methylbenzyl-alcohol (9), were isolated from fermentation cultures of a deep-sea sediment-derived fungus, Aspergillus insulicola. Their planar structures were elucidated based on the 1D and 2D NMR spectra and HRESIMS data. The absolute configurations of compounds 1–3 were determined by ECD calculations. Compound 3 represented a rare fully symmetrical isobenzofuran dimer. All compounds were evaluated for their α-glucosidase inhibitory activity, and compounds 1, 4–7, and 9 exhibited more potent α-glucosidase inhibitory effect with IC50 values ranging from 17.04 to 292.47 μM than positive control acarbose with IC50 value of 822.97 μM, indicating that these phenolic compounds could be promising lead compounds of new hypoglycemic drugs.

Research Progress of α-Glucosidase Inhibitors Produced by Microorganisms and Their Applications

“…Figure 2 shows the structur representative compounds. In their study, Zhao et al [27] conducted fermentation using Aspergillus and dis ered that various polyhydroxyphenolic compounds isolated from the fermentation tures exhibited α-glucosidase inhibitory activity. The IC50 values for these compou ranged from 17.04 ± 0.28 to 292.47 ± 5.87 µM.…”

“…Among them, scleroderolide (5) showed the most potent α-glucosidas hibitory activity, with an IC50 value of 48.7 µM. Manuel et al [30] isolated two new pol tides with novel structures, minimoidiones A and B, along with the known compou preussochromone C, corymbiferone, and 5-hydroxy-2, 7-dimethoxy-8-methylnaph In their study, Zhao et al [27] conducted fermentation using Aspergillus and discovered that various polyhydroxyphenolic compounds isolated from the fermentation cultures exhibited α-glucosidase inhibitory activity. The IC 50 values for these compounds ranged from 17.04 ± 0.28 to 292.47 ± 5.87 µM.…”

Thiolactones and Δ8,9-Pregnene Steroids from the Marine-Derived Fungus Meira sp. 1210CH-42 and Their α-Glucosidase Inhibitory Activity

“…The evaluation of α-glucosidase inhibitory activity was performed with reference to previously reported literature [31,32]. All the assays were carried out under 0.1 M PBS buffer (pH 7.4, Sigma).…”

p-Terphenyl and Diphenyl Ether Derivatives from the Marine-Derived Fungus Aspergillus candidus HM5-4

“…Almost all of these marine-derived p-triphenyls have cytotoxic effects, but some have neuroprotective and antibacterial effects. For this reason, in the process of searching for new bioactive natural products from marine-derived fungi [17][18][19][20], we carried out chemical studies on A. candidus, a fungus from a marine sponge which was collected from the coast of Lingao County, Hainan Province. Two undescribed p-terphenyl derivatives, asperterphenylcins A-B (1-2), and two undescribed diphenyl ether derivatives, asperdiphenylcins A-B (3-4), together with three previously described p-terphenyl derivatives-4 ′′ -deoxyterprenin (5), terphenyllin (6), and 3 ′′ -hydroxyterphenyllin (7; Figure 1)-were isolated from the crude EtOAc extract of a solid-rice culture of the marine sponge-derived fungus A. candidus HM5-4.…”