Two new lanostanoid glycosides isolated from a Kenyan polypore Fomitopsis carnea

Winnie Chemutai Sum; Sherif S Ebada; Didsanutda Gonkhom; Cony Decock; Rémy Bertrand Teponno; Josphat Clement Matasyoh; Marc Stadler

doi:10.3762/bjoc.19.84

Two new lanostanoid glycosides isolated from a Kenyan polypore Fomitopsis carnea

Beilstein J Org Chem. 2023 Aug 2:19:1161-1169. doi: 10.3762/bjoc.19.84. eCollection 2023.

Authors

Winnie Chemutai Sum^{1

2}, Sherif S Ebada^{1

3}, Didsanutda Gonkhom⁴, Cony Decock⁵, Rémy Bertrand Teponno^{1

6}, Josphat Clement Matasyoh⁷, Marc Stadler^{1

2}

Affiliations

¹ Department of Microbial Drugs, Helmholtz Centre for Infection Research GmbH (HZI), Inhoffenstraße 7, 38124 Braunschweig, Germany.
² Institute of Microbiology, Technische Universität Braunschweig, Spielmannstraße 7, 38106 Braunschweig, Germany.
³ Department of Pharmacognosy, Faculty of Pharmacy, Ain Shams University, 11566 Cairo, Egypt.
⁴ Center of Excellence in Fungal Research, School of Science, Mae Fah Luang University, 333 Muang, Chiang Rai, 57100 Thailand.
⁵ Mycothéque de l' Universite Catholique de Louvain (BCCM/MUCL), Place Croix du Sud 3, B-1348 Louvain-la-Neuve, Belgium.
⁶ Department of Chemistry, Faculty of Science, University of Dschang, P. O. Box 67, Dschang, Cameroon.
⁷ Department of Chemistry, Egerton University, P.O. Box 536, 20115, Njoro, Kenya.

Abstract

Chemical exploration of solid-state cultures of the polypore Fomitopsis carnea afforded two new C31 lanostane-type triterpenoid glycosides, forpiniosides B (1) and C (2) together with two known derivatives, namely 3-epipachymic acid (3) and (3α,25S)-3-O-malonyl-23-oxolanost-8,24(31)-dien-26-oic acid (4). The structures of the isolated compounds were established based on HRESIMS and extensive 1D and 2D NMR experiments. All the isolated compounds were assessed for their antimicrobial and cytotoxic activities. Among the tested compounds, forpinioside B (1) exhibited significant antimicrobial activity against Staphylococcus aureus and Bacillus subtilis at MIC values comparable to gentamycin and oxytetracycline (positive controls), respectively.

Keywords: Fomitopsis carnea; Polyporales; antimicrobial activity; lanostane glycosides.

Grants and funding

Our research benefitted from funding by the European Union’s Horizon 2020 research and innovation program (RISE) under the Marie Skłodowska‐Curie grant agreement No. 101008129, project acronym “Mycobiomics” (lead beneficiaries J.C.M. and M.S.). W.C.S. was supported by a doctoral scholarship funding from the German Academic Exchange Service (DAAD) program number 57507871. In addition, the financial grant of the Alexander von Humboldt Foundation (AvH) (Bonn, 3.4-CMR-Hub) and AvH Georg-Forster Fellowship for Experienced Researchers stipend (Ref 3.4-1222288-EGY-GF-E) to S.S.E. is acknowledged.