Effects of Vibrio cholerae on fatty acid profiles in Isochrysis galbana

Abstract

We determined the effects on metabolism and fatty acid profiles in Isochrysis galbana when co-cultured with Vibrio cholerae. Monospecific cultures of I. galbana did not experience any changes in cell density, growth rate, organic dry weight, heterotrophic bacteria, chlorophyll a content, maximun electron transport rate (ETRm) or maximum photochemical quantum yield of photosystem II (Fv/Fm) values when co-cultured with V. cholerae. The growth of pathogenic V. cholerae was inhibited in co-cultures and the lipid content was higher compared to the monospecific cultures of I. galbana. The I. galbana-V. cholerae co-cultures had similar total saturated fatty acids (SFAs) content (53.2%) versus I. galbana cultures (55.6%). Total monounsaturated fatty acids (MUFAs) content was higher in monospecific I. galbana cultures than in the co-cultures. The total polyunsaturated fatty acids (PUFAs) content was higher in co-cultures (23.2%) versus monospecific cultures (15.9%). The interaction between I. galbana and V. cholerae altered the fatty acid levels in I. galbana cells and increased the production of linoleic acid (C18:2), linolenic acid (C18:3), gamma-linolenic acid (C18:3n6), eicosatrienoic acid (C20:3n-3), and eicosatetraenoic acid (C20:4).