Abstract:
Optimum conditions of grouth and production of polyumsaturated fatty acid (omega-3 : DHA, Docosahexaenoic acid) in 3 species of thraustochytrids (Schizochytrium spp.) isolated from fallen mangrove leaves at, Kung Kra Ben Bay, Chanthaburi Province were revealed. The were grown in liquid media (glucose and extracted yeast = 6:1%) at various temperatures (15, 25 and 35 C), and salinites (5, 15 and 25 ppt) for 8 days of incubation. The results showed that isolate Schizochytrium limacinum BUCACD 032 produced the highest DHA content a compared to those of Schizochytrium mangrovei BUCARA 021 and Schizochytrium sp.1 BUCAAA 093. The isolate Schizochytrium limacinum BUCACD 032 yielded 18.21 g/L of biomass and 145.50 mg/g dry weight of DHA content (2,647.51 mg/L yield of DHA) from 6 day incubation at 25 C and 25 ppt salinity. The isolate Schizochytrium mangrovei BUCARA 021 produced 17.67 g/L of biomass and 115.16 mg/g dry weight of DHA content (2,070.59 mg/L yield of DHA) from 4 day incubation at 25C and 15 ppt salinity. While the optimum temperature and salinity of isolate Schizochytrium sp.1 BUCAAA 093 were 15C and 25 ppt of 4 day incubation yielded 4.82 g/L of biomass and 13.85 mg/g dry weight of DHA contents (68.21 mg/L yield of DHA).