桂花种子皮黑色素提取及影响其稳定性因素分析

采用碱性溶液提取、酸水解、多种有机溶剂萃取沉淀等工艺手段分离纯化了桂花种子皮色素,呈天然黑色,其得率为0.34%(以湿原料为准)。随后,对该色素的理化性质等进行了较系统的研究。结果表明,桂花种子皮黑色素耐光、耐热;对还原剂较稳定;对强氧化荆不够稳定;碱性条件下较稳定;Cu2 、Ca2 、Fe3 、Zn2 等金属离子对该色素有护色、增色作用;Mg2 、Al3 、Na 虽有减色作用,但不明显, 是一种性能优良的天然黑色素。

Extraction of melanin from Osmanthus fragrans' seeds and its' stability

The extraction technology for the melanin -like pigments derived from Osmanthus fragrans' seeds and their physical and chemical properties were studied. The melanin was isolated from Osmanthus fragrans' seeds by alkaline extraction, acid hydrolysis, and repeated precipitation with a yield of 0.34% (on wet basis). Physical and chemical properties of the melanin revealed that the melanin was stable to light and temperature, stable in alkaline solution and reducing agents, but it had less resistance against oxidant. The metal ions, Ca2 , Cu2 , Fe3 , Zn2 could stabilize and strengthen the pigment color. Although Mg2 , Al3 , Na could reduce pigment color, the effect was not obvious.