漆树多酚的负压提取工艺及其抑制酪氨酸酶活性的研究

Phenolic Extracts from Rhus verniciflua Stokes Woods by Vacuum Extraction and Their Anti-tyrosinase Activities

采用负压提取工艺从漆树中提取漆树多酚,并研究其对酪氨酸酶活性的抑制作用。通过单因素和响应曲面试验优化负压提取漆树多酚的最佳工艺条件为真空度0.082 MPa,乙醇体积分数83%,时间1.5 h,液料比20∶1(m L∶g),提取次数2次,漆树多酚得率为2.193%。通过溶剂逐级萃取漆树多酚,得到含漆树多酚53.43%的乙酸乙酯萃取物,其对酪氨酸酶具有较强作用,抑制率为63.4%,相对抑制率50%的乙酸乙酯萃取物质量浓度为308 mg/L。对酪氨酸酶单酚酶的抑制效应表现为迟滞效应,500 mg/L乙酸乙酯萃取物能将反应初速度由29μmol/(L·min)降至8μmol·(L·min)。通过Lineweaver-Burk图显示对二酚酶的抑制作用表现为混合型抑制。

The polyphenols were extracted from Rhus verniciflua Stokes by vacuum extraction, and the anti-tyrosinase activities were studied. The optimal conditions were investigated through single factor and response surface method. The optimal parameters were vacuum degree 0. 082 MPa, ethanol volume fraction 83%, extraction time 1.5 h, liquid-solid ratio 20：1 （mL： g）, and extracted twice. At these conditions, the yield of polyphenol was 2. 193%. Though the extraction, the ethyl acetate extract with 53.43% of phenolic was obtained and the inhibitory rate of tyrosinase was 63.4%. The ethyl acetate extract concentration leading to 50% inhibitory rate was 308 mg/L. The ethyl acetate extract could extend the lag time of tyrosine monophenolase, and 500 mg/L of extract could decrease the velocity from 29 μmol/（ L. min） to 8 μmol/（ L·min）. The ethyl acetate extract functioned as a hybrid inhibition of tyrosine diphenolase by Lineweaver-Burk plots.