Volatile metabolites profiling of a Chinese mangrove endophytic Pestalotiopsis sp. strain

Abstract

Pestalotiopsis JCM2A4, an endophytic fungus originally isolated from leaves of the Chinese mangrove plant Rhizophora mucronata, produces a mixture of volatile metabolites. As determined by gas chromatography and gas chromatography/mass spectrometry (GC/GC-MS), 18 compounds representing all of the hexane extract were identified. Higher amounts of oil-based straight-chained alkyl (mono- and di-methyl) esters and fatty acids were found to compose major volatile chemotype which accounted for 78.65 and 14.52% of this organism, respectively. The main components was demonstrated to be pentadecanoic acid, 14-methyl-, methyl ester (35.92%); octadecanoic acid, methyl ester (13.10%); nonanedioic acid, dimethyl ester (11.21%); and n-hexadecanoic acid (10.54%). Two of these components were isolated and determined to be n-hexadecanoic acid and elaidic acid by ¹H NMR and ¹H-¹H COSY spectroscopy. Antioxidant activity of the hexane extract and isolated compounds were screened using 2,2'-diphenyl-b-picrylhydrazyl (DPPH) free radical scavenging method. This is the first report to describe the volatile metabolites of mangrove endophytic Pestalotiopsis sp. strain; its specific fatty acid methyl esters (FAME) profile can be used as a tool for microbial source tracking.

Keywords: Mangrove endophytic fungus, Pestalotiopsis sp., volatile metabolites, fatty acid methyl esters (FAME) profile

African Journal of Biotechnology Vol. 12(24), pp. 3802-3806