裂殖壶菌油脂成分及抗氧化活性分析

Analysis of Components and Antioxidant Activities of Schizochytrium limacinum Oil

为研究裂殖壶菌油脂成分及抗氧化活性,采用气相色谱-质谱和核磁共振技术分别对裂殖壶菌油脂的脂肪酸组成和脂质成分进行分析,并对油脂的自由基清除能力和总抗氧化能力进行测定。结果表明:裂殖壶菌油脂的脂肪酸组成简单,主要为C14∶0(13.22%)、C16∶0(26.78%)、C22∶5n-6(DPA,13.66%)和C22∶6n-3(DHA,42.04%);其脂质成分以甘油三酯为主,含有少量游离脂肪酸,且C22∶6n-3和C22∶5n-6等多不饱和脂肪酸主要结合于甘油三酯的sn-2位。同时,裂殖壶菌油脂具有较好的DPPH、ABTS+和羟基等自由基清除能力和总抗氧化能力,且在10~50 mg/mL质量浓度范围内呈现显著的量效关系(P<0.05)。裂殖壶菌油脂富含C22∶6n-3和C22∶5n-6等多不饱和脂肪酸,且具有较好的抗氧化活性,因此其具有较高的营养价值和功能油脂开发潜力。本研究为裂殖壶菌油脂成分分析、抗氧化活性评价以及功能性油脂开发提供了理论依据。

In order to study the oil components and antioxidant activities of Schizochytrium limacinum oil,the fatty acid compositions and oil components of S.limacinum oil were analyzed by GC-MS and NMR,respectively,and the free radical scavenging rates and total antioxidant capacity were also determined in the present paper.The experimental results indicated that the fatty acid composition of S.limacinum oil was simple,and chiefly consisted of C14:0(13.22%),C16∶0(26.78%),C22∶5n-6(13.66%)and C22∶6n-3(DHA,42.04%).Moreover,S.limacinum oil was primarily composed of triglycerides,and also contained a small amount of free fatty acids.Meanwhile,C22∶6n-3 and C22∶5n-6 were preferably combined with the sn-2 position of the triglycerides.Additionally,S.limacinum oil had great total antioxidant capacities and scavenging capacities of free radicals,such as DPPH,ABTS+and hydroxyl radicals,and had a dose-effect relationship within the concentration range of 10~50 mg/mL(P<0.05).S.limacinum oil was rich in C22∶6n-3 and had great antioxidant activities,therefore it had high nutritional value and potentiality for the development and application of functional oil.This study provided a theoretical basis for the component analysis,antioxidant activity evaluation and development of S.limacinum oil.