徐闻珊瑚礁自然保护区可培养富脂海洋微藻的生物多样性

The biodiversity of culturable lipid-rich microalgae from Xuwen coral reef nature reserve

从徐闻珊瑚礁自然保护区（20°10′–20°27′N,109°50′–109°24′E）潮间带采集海水和泥沙样品,用f/2-medium培养液富集培养其中的海洋微藻,采用基于96孔板的＂稀释分配＂结合＂微吸管剔除＂的方法分离培养海洋微藻,采用微藻形态学观察、18S rDNA序列分析及其系统进化树构建的方法分析鉴定分离培养的藻株,采用尼罗红染色法检测和分析海洋微藻细胞中的脂质。目的就是要分析研究徐闻珊瑚礁自然保护区潮间带可培养富脂海洋微藻的生物多样性,为富脂海洋微藻的研究开发奠定基础。结果分离、培养、鉴定并储藏了118株海洋微藻（Genbank登录号为KU561102-KU561219）,含48个种,分布于硅藻门（Bacillariophyta）、绿藻门（Chlorophyta）和定鞭金藻门（Haptophyta）3个门的6纲、22目、24个科、28个属。其中,有37株为富脂微藻,含22个种,分布于硅藻门和绿藻门2个门的4纲、11目、12个科、16个属;优势属为双眉藻属（Amphora）,含22株,占分离培养藻株的18.6%;含脂量最高的种群为辐节藻属（Stauroneis）,含Stauroneis anceps,Stauroneis gracilior,和2株Stauroneis kriegeri,共4株海洋微藻。这表明徐闻珊瑚礁自然保护区潮间带可培养的富脂海洋微藻的物种丰富多样,可能是发掘多不饱和脂肪酸和生物柴油的理想资源。

In order to analyze the biodiversity of culturable lipid-rich marine microalgae from the intertidal zone of Xuwen coral reef nature reserve and lay the foundation for research and development of lipid-rich marine microalgae, the samples of sea water and soil were collected from the intertidal zone of Xuwen coral reef nature reserve（20°10′–20°27′N, 109°50′–109°24′E）. The marine microalgae in the samples were cultured with f/2-medium, isolated by dilution and distribution technique combined with micropipette technique based on 96-well plate, identified by morphological observation of the microalgal isolates and sequence analysis and phylogenetic tree construction of the microalgal 18 S rDNA sequences. The lipids of microalgal isolates were detected and analyzed by Nile red staining method. A total of 118 marine microalgal strains were isolated, cultured and identified（Gen Bank accession numbers were KU561102-KU561219） from the intertidal zone of Xuwen coral reef nature reserve, which represented 48 species, distributed in Bacillariophyta, Chlorophyta and Haptophyta 3 phyla, 6 classes, 22 orders, 24 families, 28 genera. Amongst, 37 strains of the isolated microalgae were lipid-rich, represented 22 species, distributed in Bacillariophyta and Chlorophyta 2 phyla, 4 classes, 11 orders, 12 families, 16 genera. The predominant genus of lipid-rich microalgae was Amphora containing 22 strains, which occupied a great proportion of 18.6%. The genus with the highest lipid content was Stauroneis, containing 1 strain of Stauroneis anceps, 1 strain of Stauroneis gracilior and 2 strains of Stauroneis kriegeri. These results indicated that the culturable lipid-rich microalgae in the intertidal zone of Xuwen coral reef nature reserve were diverse species, and would be the ideal resources for research and development of polyunsaturated fatty acids and biodiesel.