This study was aimed to isolate fast-growing thraustochytrids and the influence of seasonal variation in fatty acid composition from the mangrove habitat. The thraustochytrids were isolated from fallen yellowish or green mangrove leaves, in four seasons, including winter, summer, rainy, and post rainy season in one year. The thraustochytrids were analyzed for biomass production, total lipid content, and fatty acid profile. The thraustochytrid isolates showed biomass yield and total lipid content in the range of 14.12 ± 0.69 to 22.98 ± 0.53 g/L and 34.98–58.86% per dry cell weight, respectively. The isolates showed two dominant fatty acids, palmitic acid (PA) as saturated fatty acid (SFA) and docosahexaenoic acid (DHA) as long-chain polyunsaturated fatty acids (LC-PUFA) in total fatty acid (TFA) content. The significant differences (P < 0.05) were observed for seasonal variations in SFA and DHA content in summer isolates and winter isolates. The maximum DHA content with 47.12% of TFA, recorded in winter (January) isolates and summer (April) isolates with SFA 68.82% of TFA. The results from this study were verified the hypothesis that the presence of high DHA producing thraustochytrids in lower temperature season in the same habitat. These findings have also emphasized the role of the environmental temperature conditions and the importance of thraustochytrid fatty acid composition as a dietary biomarker. Also, it revealed the ecological significance of thraustochytrid in DHA enrichment in the food web of the marine ecosystem. These findings could be useful while isolating thraustochytrids according to seasons for industrial application for omega 3 fatty acids and biodiesel production.

这项研究的目的是从红树林生境中分离快速生长的破囊壶菌和脂肪酸组成的季节性变化的影响。在四个季节（包括冬季，夏季，雨季和一年后的雨季）中，从落下的淡黄色或绿色红树林叶子中分离出破囊壶菌。分析了破囊壶菌的生物量产生，总脂质含量和脂肪酸谱。破囊壶菌的分离物显示，每干细胞重量的生物量产量和总脂质含量分别为14.12±0.69至22.98±0.53 g / L和34.98-58.86％。分离物显示两种主要脂肪酸，即总脂肪酸（TFA）含量中的棕榈酸（PA）为饱和脂肪酸（SFA）和二十二碳六烯酸（DHA）为长链多不饱和脂肪酸（LC-PUFA）。显着差异（P <0.05）观察到夏季分离物和冬季分离物的SFA和DHA含量存在季节性变化。冬季（1月）分离株和夏季（4月）SFA占TFA的68.82％记录到的最大DHA含量为TFA的47.12％。这项研究的结果证实了以下假设：在相同的生境中，在较低的温度季节中会产生高DHA的破囊壶菌。这些发现还强调了环境温度条件的作用以及破囊壶菌脂肪酸组合物作为饮食生物标志物的重要性。此外，它还揭示了破囊壶菌在海洋生态系统食物网中DHA富集中的生态意义。这些发现在根据季节分离破囊壶菌以用于欧米茄3脂肪酸和生物柴油生产的工业应用中可能是有用的。