Bioactive compounds from marine <em>Stachybotrys</em> sp. QL23

Abstract

During our ongoing search for bioactive compounds from microorganisms, the marine fungus <em>Stachybotrys</em> sp. QL23 was isolated from a sediment sample collected from Qarun Lake, El Fayoum governorate, Egypt and biologically screened to produce bioactive compounds. The fungal extract showed moderate to high activity against Gram positive and Gram-negative bacteria assayed. The genotypic characterisation of <em>Stachybotrys</em> sp QL23 has been deduced basically on its 18S rRNA gene sequencing. Pre-chemical studies of the strain extract using different chromatographic techniques afforded the major bioactive metabolites, ergosterol (1) and linoleic acid (2), and their chemical structures were assigned using 1D and 2D NMR and Spectroscopy and HR-EI mass spectrometry. In this article, we present the isolation and taxonomical characterisation of the producing fungal strain, along with the study of antimicrobial activity of the strain extract and compounds 1-2 using a set of microorganisms. The study of the QL23 using cervix carcinoma cell line (KB-3-1) extract has been reported as well.