Hexacyclic 6/6/6/5/6/6 Spirosteroids Produced by a Marine-Derived Fungus Galactomyces pseudocandidus and Antifungal Activity against Candida Species

IF 3.7 2区生物学 Q2 CHEMISTRY, MEDICINAL

Journal of Natural Products Pub Date : 2026-09-25 Epub Date: 2026-03-02 DOI:10.1021/acs.jnatprod.6c00038

Hitoshi Kamauchi, Mikuru Kuroda, Mitsuaki Suzuki, Kanako Usui, Yuki Yatsui, Yuka Kiba, Masashi Kitamura, Yoshiaki Sugita

{"title":"Hexacyclic 6/6/6/5/6/6 Spirosteroids Produced by a Marine-Derived Fungus Galactomyces pseudocandidus and Antifungal Activity against Candida Species","authors":"Hitoshi Kamauchi, Mikuru Kuroda, Mitsuaki Suzuki, Kanako Usui, Yuki Yatsui, Yuka Kiba, Masashi Kitamura, Yoshiaki Sugita","doi":"10.1021/acs.jnatprod.6c00038","DOIUrl":null,"url":null,"abstract":"Two spirosteroids, epoformsterols A and B (1 and 2), featuring a highly fused 6/6/6/5/6/6 hexacyclic framework, were isolated from the marine-derived fungus Galactomyces pseudocandidus. The structures of 1 and 2 were elucidated by NMR, HRMS, and single-crystal X-ray diffraction. The absolute configuration of 1 was established by comparison of calculated and experimental ECD spectra, and that of 2 was assigned by ECD comparison with 1. Compounds 1 and 2 exhibited inhibitory activity against Candida auris and C. albicans with MIC values of 3.12−12.5 μg/mL, and MFC/MIC ratios suggested a fungistatic mode of action. Both compounds also inhibited C. rugosa lipase (CRL) in a model enzyme assay, with IC50 values of 5.7 and 8.9 μM, respectively. These results identify a distinctive class of fungal steroids with antifungal activity.","PeriodicalId":47,"journal":{"name":"Journal of Natural Products ","volume":"89 9","pages":"2429–2435"},"PeriodicalIF":3.7000,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Natural Products ","FirstCategoryId":"99","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acs.jnatprod.6c00038","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2026/3/2 0:00:00","PubModel":"Epub","JCR":"Q2","JCRName":"CHEMISTRY, MEDICINAL","Score":null,"Total":0}

引用次数: 0

Abstract

Two spirosteroids, epoformsterols A and B (1 and 2), featuring a highly fused 6/6/6/5/6/6 hexacyclic framework, were isolated from the marine-derived fungus Galactomyces pseudocandidus. The structures of 1 and 2 were elucidated by NMR, HRMS, and single-crystal X-ray diffraction. The absolute configuration of 1 was established by comparison of calculated and experimental ECD spectra, and that of 2 was assigned by ECD comparison with 1. Compounds 1 and 2 exhibited inhibitory activity against Candida auris and C. albicans with MIC values of 3.12−12.5 μg/mL, and MFC/MIC ratios suggested a fungistatic mode of action. Both compounds also inhibited C. rugosa lipase (CRL) in a model enzyme assay, with IC₅₀ values of 5.7 and 8.9 μM, respectively. These results identify a distinctive class of fungal steroids with antifungal activity.

查看原文本刊更多论文

六环类6/6/6/5/6/6假假丝酵母产螺甾体及其对假丝酵母菌的抗真菌活性。

从海洋来源的假假假半乳糖真菌中分离到两个螺甾体，分别为epoformsterols A和B(1和2)，具有高度融合的6/6/6/5/6/6六环框架。1和2的结构通过核磁共振、HRMS和单晶x射线衍射进行了鉴定。通过计算和实验ECD谱的比较确定了1的绝对构型，通过ECD与1的比较确定了2的绝对构型。化合物1和2对耳念珠菌和白色念珠菌具有抑制活性，MIC值为3.12 ~ 12.5 μg/mL， MFC/MIC比值表明其具有抑菌作用。在模型酶实验中，这两种化合物还能抑制C. rugosa脂肪酶（CRL）， IC50值分别为5.7 μM和8.9 μM。这些结果确定了一类具有抗真菌活性的真菌类固醇。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Journal of Natural Products 生物-药学

CiteScore

9.10

自引率

5.90%

发文量

294

审稿时长

2.3 months

期刊介绍： The Journal of Natural Products invites and publishes papers that make substantial and scholarly contributions to the area of natural products research. Contributions may relate to the chemistry and/or biochemistry of naturally occurring compounds or the biology of living systems from which they are obtained. Specifically, there may be articles that describe secondary metabolites of microorganisms, including antibiotics and mycotoxins; physiologically active compounds from terrestrial and marine plants and animals; biochemical studies, including biosynthesis and microbiological transformations; fermentation and plant tissue culture; the isolation, structure elucidation, and chemical synthesis of novel compounds from nature; and the pharmacology of compounds of natural origin. When new compounds are reported, manuscripts describing their biological activity are much preferred. Specifically, there may be articles that describe secondary metabolites of microorganisms, including antibiotics and mycotoxins; physiologically active compounds from terrestrial and marine plants and animals; biochemical studies, including biosynthesis and microbiological transformations; fermentation and plant tissue culture; the isolation, structure elucidation, and chemical synthesis of novel compounds from nature; and the pharmacology of compounds of natural origin.