Palmitic acid and long-chain polyunsaturated fatty acids dominate in mycelia of mangrove Halophytophthora and Salispina species in Taiwan

Abstract

Marine oomycetous species produce, among other fatty acids, omega-6 arachidonic acid (ARA) and omega-3 eicosapentaenoic acid (EPA), with implications for the industrial potential of this group of organisms and the need to find an isolate with high production. This study screened 14 isolates of marine oomycetous species: Halophytophthora avicenniae, H. batemanensis, H. exoprolifera, H. polymorphica and Salispina spinosa cultured from fallen mangrove leaves in Taiwan for 24 saturated and unsaturated fatty acids in their mycelia. This paper is the first to report C18:1n-7 vaccenic acid, C20:1 eicosenoic acid, C24:1 nervonic acid, C20:2n-6 eicosadienoic acid, C22:4n-6 adrenic acid, C20:4n-3 eicosatetraenoic acid and C22:5n-3 docosapentaenoic acid in mycelia of Halophytophthora and Salispina species, and the fatty acid profiles of H. batemanensis and H. exoprolifera. Five fatty acids were dominant in the mycelia of the isolates, i.e. C16:0 palmitic acid, C18:1n-9 oleic acid, C18:2n-6 linoleic acid, C20:4n-6 arachidonic acid and C20:5n-3 eicosapentaenoic acid. For the essential fatty acids, S. spinosa produced the highest level of arachidonic acid (27-31% of total fatty acid (TFA), 141-188 mg l(-1) yield) while H. avicenniae IMB212 produced the highest percentage of EPA (15% of TFA) while H. polymorphica 1MB227 produced the highest yield (96 mg l(-1)). Different species and isolates of the same species produced different fatty acid profiles, and further research effort may yield a high production isolate of industrial significance and also important fatty acids from the marine environment.