- 期刊
茯苓固態發酵米糠產物之活性成分和抑制酪胺酸酶之研究
Study of Active Components and Tyrosinase Inhibition of Poria cocos Solid-state Fermented Rice Bran Products
摘要
茯苓（Poria cocos）為中國傳統的藥用真菌，主要生物活性成分為多醣及三萜類，據藥理研究證實其具有調節免疫、抗氧化、抗發炎和抑制酪胺酸酶等多種生理功能。本研究之目的為（1）以射頻安定化後的米糠、糙米作為基質，進行四週的茯苓固態發酵後，再分別以水和乙醇作為溶劑進行微波萃取，分析其活性成分和抗氧化活性。（2）將不同濃度的萃取液進行酪胺酸酶抑制實驗，並探討其抑制機制和動力學。結果顯示，當使用米糠作為發酵基質時，茯苓菌絲體的含量較高，達9.75%，且經由微波萃取後萃取液中含有較多的粗三萜、類黃酮及總多酚成分，因此有較佳的抗氧化能力，表示相較於糙米基質，米糠中的活性成分能使茯苓固態發酵產物有較佳的抗氧化能力。當使用50～200 μg/mL之茯苓固態發酵米糠及糙米產物的水及乙醇萃取液進行酪胺酸酶抑制試驗，而以200 μg/mL茯苓固態發酵米糠產物的水、乙醇萃取液有較好的抑制率，分別達27.76%及34.63%，進一步分析茯苓固態發酵米糠產物的水萃取液和乙醇萃取液對酪胺酸酶的反應，分別為非競爭型抑制和無競爭型抑制混合物。
並列摘要
Poria cocos is a traditional Chinese medicinal fungus, the main bioactive compounds are polysaccharides and triterpenoids. According to the pharmacological studies, it has several effects such as immunoregulation, anti-oxidant, anti-inflammatory, and inhibiting tyrosinase. The objectives of this study were (1) to use the stabilization of rice bran by radio frequency and brown rice as a medium to cultivate P. cocos solid-state fermented product for 4 weeks, and then use microwave-assisted extraction with water and ethanol as solvents to analyze the active compounds and antioxidant activity, (2) to perform tyrosinase inhibition kinetics and mechanism with different concentrations of extracts. The results showed that when using rice bran as a medium, the fermented product contains more mycelium about 9.75% and higher triterpenes, flavonoids, and total polyphenols after microwave-assisted extraction. Therefore, rice bran superior to brown rice, the P. cocos can use the ingredients in the rice bran and producing the active compounds to make better antioxidant activities. When using 50~200 μg/mL water and ethanol extracts from P. cocos solid-state fermented rice bran and brown rice product for in vitro tyrosinase inhibition, at the concentration of 200 μg/mL water and ethanol extracts from P. cocos fermented rice bran product had better inhibition 27.76% and 34.63%, respectively. The water extract and ethanol extract from P. cocos solid-state fermented rice bran for tyrosinase were noncompetitive and uncompetitive inhibition compounds, respectively.