Studies on Antioxidant Activity of Endo Phytic Fungi Isolated from Morinda citrifolia (Noni) and Construction of Phylogenetic Tree

本文以诺丽(Morinda citrifolia Linn.)果和叶中分离得到的8株内生真菌为研究对象，使用乙酸乙酯萃取其次生代谢产物。采用DPPH自由基清除法、ABTS自由基清除法和FRAP总还原能力分析其抗氧化活性，用福林–肖卡法和AlCl3显色法测定其总多酚(TPC)、总黄酮(TFC)含量并构建其系统发育树。结果表明，诺丽8株内生真菌菌株的抗氧化活性均较强，其DPPH、ABTS和FRAP抗氧化能力的最高值，分别为31.24 mmol/L-Trolox/g DW、10.92 mmol/L-Trolox/g DW和9.62 mmol/L。在1.0 mg/mL时，TPC、TFC含量范围值分别为17.99~79.03 mg/g，48.38~158.97 mg/g。较强的抗氧化活性，使得诺丽内生真菌在探寻天然抗氧化活性产物中具有重要价值。 The secondary metabolites were obtained by using ethyl acetate as solvent for 8 kinds of fermen-tation liquid extraction from endophytic fungi of Noni leaves and fruits. The antioxidant activity was analyzed by DPPH radical scavenging method, ABTS radical scavenging assay and FRAP total reduction capability, and the total polyphenols content (TPC) and total flavonoid content (TFC) of the secondary metabolites were determined by using Folin-reagent method and AlCl3 colorimetric method. The results showed that the antioxidant activities of 8 strains of Noni endophytic fungi were strong, the highest value of DPPH, ABTS and FRAP of the antioxidant capacity was 31.24 mmol/L-Trolox/g DW, 10.92 mmol/L-Trolox/g DW and 9.62 mmol/L, respectively. At 1 mg/mL, the content range of TPC and TFC was 17.99 - 79.03 mg/g, 48.38 - 158.97 mg/g, respectively. The strong antioxidant activity made the Noni endophytic fungi have the important value in exploring the natural antioxidant activity of products.