摘要
将510nm紫外吸光度为0.8的红曲色素水溶液置于室内可见光下,吸光度4d减少了近50%,而水溶液的pH值在6～10范围内光稳定性较好;可见光作用同样吸光度的色素乙醇溶液,7d吸光度减少50%左右,在20%～95%范围内乙醇浓度越低,色素光稳定性越好;将色素液置于培养皿中在距离紫外灯(40W)15cm处照射2h得到与以上类似的结果,紫外灯照射可作为测定红曲色素光稳定性的一种可靠方法。
The water solutions of monascus pigments (absorption in 510nm is 0.8) were put in the visible light, the absorption reduced about 50% after 4d, in which PH6~8 showed better results; In ethanol solution(same absorption), the absorption reduced 50% after 7d, in the content of 20%～95% , the lower concentration the better results. When the solution was put in 40W UV irradiation light, the same results appeared, so UV irradiation was a reliable method to determine the photostability of monascus pigments.
