玄米萃取物對於抗氧化、抑制黑色素生成及致突變的研究

Study of Brown Rice Extract on the Efficacy of Antioxidation, Inhibiting the Formation of Melanin and Antimutagenicity

劉薏蓉(I-Jung Liu) ； 陳柏文(Po-Wen Chen) ； 黃秉炘(Ping-Hsin Huang)

《耕莘學報》 12期 (2014/12) Pp. 67-74

摘要

本研究採用乾燥的發芽糙米（玄米，Brown Rice）為材料，經95%乙醇萃取，再進行抗氧化性、抑制黑色素生成以及致突變性等測試。在抗氧化方面，50.0 mg/mL玄米萃取物清除DPPH自由基的效果相當於同濃度Ascorbic acid的76.8%、BHA的77.0%以及BHT的78.7%；100.0 mg/mL玄米萃取物螯合亞鐵離子的效果相當於同濃度EDTA的99.6%；1.0 mg/mL玄米萃取物清除超氧陰離子的效果相當於同濃度BHT的123.1%。在抑制黑色素生成方面，玄米萃取物抑制生成黑色素的中間產物Dopachrome生成的能力隨濃度得增加而增加，且其IC50為0.055 mg/mL。另由沙門氏菌恢復突變性試驗之結果顯示，經Ames test TA98(±S9)，sample濃度5%、2.5%、1.25%、0.625%、0.3125%與對照組比較，結果顯示突變數皆未超過2倍以上，因此判斷玄米萃取物於使用5%以下濃度應無致突變性的可能。綜合上述結果，玄米萃取物應可考量作為抗老化、抑制黑斑及安全的天然美容保健材料。

關鍵字

玄米 ； 抗氧化 ； 黑色素 ； 致突變

並列摘要

The dried brown rice were extracted by 95% ethanol, the ethanolic extract was examined on the effects in the antioxidative activity, the inhibiting the formation of dopachrome and the antimutagenicity. In the concentration of 50.0 mg/ mL, the ability of the ethanolic extract for the scavenging DPPH free radicals is 76.8%, 77.0% and 78.7% to Ascorbic acid, BHA, and BHT, respectively. In 100.0 mg/mL, the ability for the chelating ferrous ion is 99.6% to EDTA. In addition, in 1.0 mg/mL, the ability for the scavenging superoxide anion radicals is 123.1% to BHT. The results indicate the ethanolic extract behaves antioxidative activity. The IC50 of the ethanolic extract for the formation of dopachrome is 0.055 mg/mL. Indicating that the ethanolic extract shows the activity for inhibiting melanogenesis. The ethanolic extract does not possess mutagenicity. In conclusion, the ethanolic extract of brown rice may be a safe, natural, and healthy material for whitening skin and keeping genes in cells from chemical injury..

並列關鍵字

Brown rice ； Antioxidation ； Melanin ； Antimutagenicity