海鞘中产油脂共附生真菌的筛选及脂肪酸组成成分分析

从20株海鞘共附生真菌中筛选产油脂菌。采用苏丹混合溶液染色法初筛，摇瓶复筛，酸热法提取油脂油脂，气相色谱-质谱联用法（GC-MS）测定其脂肪酸组成，形态学观察结合分子生物学鉴定产油脂真菌。结果表明：经初筛和复筛得到3株油脂含量均达20.00%以上的菌株，分别为菌株P2-18、P1-17和P2-4，脂肪酸组成分析不饱和脂肪酸分别占其脂肪酸组成的93.90%、55.80%和65.00%。其中γ-C18:3(γ)亚麻酸、C16:1棕榈一稀酸和C18:1油酸含量最多。P2-4含23.2%的γ-C18:3(γ)亚麻酸，约占其不饱和脂肪酸的24.50%。3株真菌经形态学鉴定，结合分子生物学ITS区序列鉴定，菌株P2-4为桔青霉（Penicillium citrinum），P1-17为青霉属（Penicillium sp. 12 BRO-2013），P2-18为土曲霉（Aspergillus terreus）。因此，该海鞘共附生真菌具备开发微生物功能性油脂的潜力，具有良好的开发应用前景，值得进一步研究。
This is the first report of the screening of oil-producing endophytic fungi isolated from Ascidiacea. A mixed solution of Sudan dyes was used in the primary screen to obtain oil-producing fungi, and the shake-flask method was performed to screen for high-yield oil-producing fungi, which were then identified by morphology and molecular biology. The oil produced by three dominant strains was extracted using the acid-heating method to determine the oil content and analyze the lipid components by gas chromatography-mass spectrometry (GC-MS). The results showed that three fungi (P2-4, P1-17, and P2-18) had average oil contents above 20%, and these were identified as Penicillium citrinum, Penicillium sp. 12 BRO-2013, and Aspergillus terreus, respectively. The composition of unsaturated fatty acids from P2-18, P1-17, and P2-4 accounted for 93.9%, 55.8% and 65.0%, respectively, of total fatty acids. The main components of the oil were C18:3 ?-linolenic acid, C16:1 palmitic acid, and C18:1 oleic acid. The highest C18:3 ?-linolenic acid proportion was from P2-4, and was up to 24.5% of total unsaturated fatty acids. Ascidiacea endophytic fungi have the potential for producing microbial functional oil, which deserves further research and development.