天然棕色棉色素多组分特性的研究

Research on Multicomponent Characteristics of Naturally Brown Cotton

为了确认天然棕色棉色素的组分特性, 采用反相C18层析柱对天然棕色棉色素提取粗品进行分离, 通过高效液相色谱和紫外-可见光谱法进行研究.色素提取粗品的液相色谱表明, 在保留时间3min以内有分离度较好 的组分但数量少, 绝大部分组分处在保留时间为7-7min范围但分离度不好, 呈正态分布峰形形态（馒头峰）, 这两部分均为有色物质.采用不同浓度的甲醇水溶液（极性不同） 为流动相进行梯度淋洗, 能够将保留时间为7-7min 色素组分一定程度分离, 但被分离色素组分的液相色谱图并不是单一尖锐的峰形.色素液相色谱表明, 5% 的甲醇 溶液可以将保留时间为3min以下的色素物质进行富集,30%甲醇溶液可以对保留时间为13.5min的黄色色素物 质进行富集.不同梯度淋洗得到的色素混合物质尽管极性有差异,但紫外-可见光谱非常相似, 说明天然棕色棉的色 素的确是由极性略有不同但结构非常类似的物质组成的混合物.

To research the multicomponent characteristics of naturally brown cotton pigments,reverse- C18 chromatographic column was applied to separate the pigment of naturally brown cotton roughly and the research was conducted by HPLC and UV-visible spectrums. LC （Liquid Chromatogram） shows that there are few components with good degree of separation within 3 min retention time,and most components arewithin the retention time of 7 -17 min, but the degree of separation is poor and presents normaldistribution peak shape （steamed bun peak）. The two parts are colored matters. Methanol solutions withdifferent concentration （different polarity） were used as the mobile phase for gradient elution to separate pigment componentswith the retention timeof 7 -17 min tosome extent,but liquid chromatogram of separated pigment components is not single keen-edged peak shape. Liquid chromatogram of pigment indicates that 5% methanol solution can collect the pigment components within 3 min retention time and 30% methanol solution can collect the yellow pigment whose retention time is 13. 5 min. Although the pigment mixture gained from different gradient has different polarity, UV-visible spectrums are quitesimilar. This shows that pigments of naturally brown cotton are the mixture with different polarity andsimilar structure.