不同成熟期枸杞中类胡萝卜素含量的变化规律

Law of Changes of Carotenoids Contents in Fructus Lycii of Chinese Wolfberry (Lycium barbarum L.) at Different Mature Periods

【目的】研究枸杞类胡萝卜素的分析方法,测定枸杞5个不同成熟期类胡萝卜素含量,分析其变化规律。【方法】通过可见光吸收光谱特性分析了不同成熟期枸杞色素的主要成分,采用薄层色谱和高效液相色谱进行分离,并鉴定其成分及含量。【结果】薄层色谱法可以定性分析枸杞中色素,方法快捷、简便。高效液相色谱法可以在30min内使枸杞样品中的叶绿素、类胡萝卜素及其酯类完全分离并定性、定量分析。试验结果表明,随枸杞成熟度的增加,玉米黄素双棕榈酸酯的含量逐渐增加;β-胡萝卜素的含量变化较小;玉米黄素从青果期至绿熟期的含量是逐渐减少的,从绿熟期至红熟期的含量基本不变。【结论】枸杞在成熟过程中总类胡萝卜素含量不断增加,且主要转化为玉米黄素双棕榈酸酯。

[Objective] To study the law of changes of the carotenoids contents at different stages in Fructus Lycii of Lycium barbarum L., and the method was studied for the determination of caotenoids in the Fructus. [Method] The composition of the pigments at different stages was analyzed by UV absorption spectrum. Then the pigments was separated and identified by TLC and HPLC. [Result] The method of TLC was simple, fast, it is one of the means of pigments quality mensuration in the Fructus. A simultaneous determination of carotenoids, carotenoid esters and chlorophyll in the Fructus by HPLC in 30 rain was developed, it was also used in quantitative and qualitative analysis. With maturation of Fructus Lycii, the content of zeaxanthin dipalmitate increased and became the principal pigment, β-carotene did not change obviously, and from green fruit stage to green mature stage the content of. zeaxanthin decreased, then held stable until red mature stage. [Conclusion] It was found that with maturation of Lycium barbarum L., the content of total carotenoids increased, the diversification of the contents mainly resulted from the increase of zeaxanthin dipalmitate.