稀硬木层孔菌的抗氧化活性及其活性成分分析

Analysis of Antioxidant Activity and Active Components of Phellinus robustus

目的以稀硬木层孔菌("桑黄"的一种)为研究对象,探索其最佳抗氧化活性组分,并分析其有效成分。方法采用溶剂萃取法得到稀硬木层孔菌的不同组分,对不同组分进行总酚和总黄酮的含量测定,DPPH、ABTS自由基清除活性测定,总还原力活性测定以及脂质过氧化物抑制活性测定,并对这些指标进行相关性分析,最后通过高效液相色谱电化学检测法(HPLCECD)技术对抗氧化活性最佳的组分进行酚类化合物成分分析。结果乙酸乙酯层具有最高的总酚、总黄酮含量及抗氧化活性,其中DPPH自由基清除活性与VC差异不显著(P>0.05)。稀硬木层孔菌的总酚含量和总黄酮含量与总还原力之间相关性强(r^2=0.984,P<0.01),经HPLC-ECD技术从中分离到原儿茶酸、香草酸和咖啡酸,其含量分别为(0.67±0.06)、(0.25±0.02)和(0.13±0.01)μg·mg^(-1),其中香草酸和咖啡酸为首次分离。结论稀硬木层孔菌乙酸乙酯层具有较高的酚类化合物和抗氧化活性,具有较好的食用和药用价值。

OBJECTIVE To determine the antioxidant activities of different extracts from Phellinus robustus（ PR） and analyze the active components of the extract with the highest antioxidant activity. METHODS PR was first extracted by ethanol and then the ethanol extract was sequentially partitioned into four fractions. To determine the antioxidant abilities of different extracts,the contents of total phenols and total flavonoids,scavenging activity on DPPH and ABTS radicals,reducing power and inhibition of lipid peroxidation were measured. RESULTS The ethyl acetate fraction（ EAF） showed the highest contents of total phenols and flavonoids and the largest antioxidant capacity,meanwhile,its DPPH radical scavenging activity was comparable to that of the positive control,ascorbic acid（ P〈0. 05）. TPC and TFC showed strong positive correlations with FRAP（ r2= 0. 984,P〈0. 01）. Three phenolic acids（ protocatechuic acid,vanillic acid and caffeic acid） had been isolated and identified from EAF by HPLC-ECD,and anilic acid and caffeic acid were first isolated from PR. CONCLUSION EAF from PR has strong potential to be a source of phenolic compounds with antioxidant proprieties and a promising source of food and drugs.