Chemical investigation of the Antarctic lichen-derived fungal strain Acremonium sp. SF-7394 yielded a new amphilectane-type diterpene, acrepseudoterin (1), and a new acorane-type sesquiterpene glycoside, isocordycepoloside A (2). In addition, three known fungal metabolites, (-)-ternatin (3), [D-Leu]-ternatin (4), and pseurotin A (5), were isolated from the EtOAc extract of the fungal strain. Their structures were mainly elucidated by analyzing their NMR and MS data. The absolute configuration of 1 was proposed by electronic circular dichroism calculations, and the absolute configuration of the sugar unit in 2 was determined by a chemical method. The inhibitory effects of the isolated compounds on protein tyrosine phosphatase 1B (PTP1B) were evaluated by enzymatic assays; results indicated that acrepseudoterin (1) and [D-Leu]-ternatin (4) dose-dependently inhibited the enzyme activity with IC50 values of 22.8 ± 1.1 μM and 14.8 ± 0.3 μM, respectively. Moreover, compound 1 was identified as a competitive inhibitor of PTP1B.
Acremonium sp., terpenoids, PTP1B, antarctic fungal metabolites
NCBI PubMed ID: 34576982Publication DOI: 10.3390/molecules26185505Journal NLM ID: 100964009Publisher: Basel, Switzerland: MDPI
Correspondence: Yim JH
; Oh H
Institutions: Division of Polar Life Sciences, Korea Polar Research Institute, Incheon, South Korea, Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan, South Korea, College of Medical and Life Sciences, Silla University, Busan, South Korea, Department of Plant Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, South Korea
Methods: 13C NMR, 1H NMR, NMR-2D, IR, inhibition studies, acid hydrolysis, UV, extraction, optical rotation measurement, CC, RP-HPLC, cell growth, HR-ESI-MS, derivatization, evaporation, flash chromatography, ECD
Found