罗汉果花气味物质量化分析方法研究

A new method for quantitative analysis of flower scent of Siraitia grosvenorii

关键词:  罗汉果, 花气味物质, 动态顶空吸附, GC-MS分析, 葫芦科

Key words:  Siraitia grosvenorii, flower scent substance, dynamic headspace adsorption(DHSA), GC-MS analysis, Cucurbitaceae

摘要:

罗汉果(Siraitia grosvenorii)是葫芦科著名的药食两用植物,广泛种植于广西桂林地区,其开花后传粉不良现象迫切需要研究解决。为了探讨罗汉果花朵气味物质与传粉者访花频率的关系以及查明传粉不良产生的原因,该文选择罗汉果雄花为材料,研究了罗汉果花朵气味物质的量化分析方法。实验采用动态顶空吸附法收集新鲜花朵的气味物质,经过洗脱、洗脱液吹氮和GC-MS分析等步骤,先后完成了花朵气味物质的收集、浓缩、分离和鉴定,最后以峰面积归一化法计算各化学组分的相对含量。结果表明:从供试花朵中检测到挥发性组分(包括萜烯类物质)5种,以及芳香烃类、烷烃类、酯类物质各1种,其中萜烯类物质的相对含量达71.07%,是供试花朵最主要的挥发性化合物。该结果高度符合葫芦科植物花朵气味的化学组分特征,并具有良好的实验重复性,表明该实验体系是收集和鉴定罗汉果花朵气味组分的理想方法,为后续开展罗汉果花气味物质研究奠定了重要基础。同时通过与葫芦科多种植物比较,发现罗汉果的花朵气味物质可能存在雌雄二型性。

Abstract:

The dioecious Siraitia grosvenorii is a famous edible and medicinal plant in Cucurbitaceae, and both the food parts and medicinal parts of this plant are their fruits. Because of the important economic value, it has been widely planted for a long history in Guilin, Guangxi, China. However, the problem of pollen limitation in S. grosvenorii is urgently needed to be solved. In order to study the relationship between flower scent substance and flower-visiting frequency, and to find out the reasons for pollen limitation, we collected the scent substance of fresh male flowers of S. grosvenorii by dynamic headspace adsorption technique. After elution of the absorption column, the eluent was concentrated by nitrogen blowing method. Subsequently, the concentrated eluent was analyzed by gas chromatography coupled with mass spectrometry(GC-MS). In this process, the collection, concentration, separation and identification of the scent substance in male flowers of S. grosvenorii were conducted. Finally, the relative content of each substance was calculated by the peak area normalization method. Among the scent substance of S. grosvenorii male flowers, we totally found five terpenes, one aromatic hydrocarbons, one alkanes and one esters, in which the terpenes occupy a relative content of 71.07%, ranking the highest content. This result showed a high agreement with that of the previous studies on composition of floral scent substance in Cucurbitaceae plants, and had good experimental reapeatability. Further analysis showed that the experiment system in this study is a solid and efficient method for the quantitative analysis of S. grosvenorii flower, laying the important foundation for the floral scent research towards the pollen limitation in this plant.