不同浓度微量元素处理对斑兰叶组培过程中挥发性物质及角鲨烯相关酶活性的影响

Variation of Volatile Aroma Compounds and Squalene-related Enzy-matic Activities in the Tissue Cultivation of Pandanus amaryllifolius under Different Concentrations of Trace Elements

为了研究不同浓度微量元素处理组培斑兰叶的挥发性物质及角鲨烯相关酶活性的变化,本研究以不同浓度锌(Zn)、镧(La)元素处理的组培斑兰叶为原料,采用GC-MS技术对其挥发性物质进行分析,并测定角鲨烯代谢关键酶活性。结果表明:不同浓度微量元素处理的组培斑兰叶挥发性物质的数量、含量均存在差异,与未处理的组培斑兰叶相比,4 mg/LZn元素处理和1、2、4 mg/LLa元素处理的组培斑兰叶中的挥发性物质较多。Zn、La元素处理均使组培斑兰叶中的醇类物质含量增加、烯烃类物质含量减少;Zn、La元素处理均使组培斑兰叶中的角鲨烯含量明显减少,2 mg/LZn元素处理使组培斑兰叶中的β-谷甾醇、豆甾醇、棕榈酸乙酯、3-甲基-2-(5H)-呋喃酮、2,3-二氢-3,5二羟基-6-甲基-4(h)-吡喃-4-酮含量增加,角鲨烯和叶绿醇含量减少;8 mg/L La元素处理组培斑兰叶的叶绿醇含量最高。角鲨烯代谢相关酶活性在组培斑兰叶培养过程中有一定变化,羊毛甾醇合成酶(LSS)和鲨烯环氧酶(SE)在混合物(愈伤组织开始分化出芽)中活性较强,角鲨烯合成酶(SQS)在不定根中活性较强。不同浓度微量元素处理对角鲨烯相关酶活性有一定影响,不同浓度Zn元素处理的组培斑兰叶中角鲨烯含量与LSS、SE、SQS酶活性均呈正相关;La元素处理组培斑兰叶中角鲨烯含量与LSS、SQS酶活性呈负相关,与SE酶活性呈正相关。研究结果丰富了微量元素调控斑兰叶挥发性物质的相关理论研究,为挖掘提高斑兰叶香气品质的组培新技术提供理论依据。

The variation of volatile aroma compounds and squalene-related enzyme activities of the tissue cultivation Pandanus amaryllifolius Roxb.leaves(PAL)treated with different concentrations of Zn and La was studied.The tile aroma compounds were analyzed by GC-MS,and the key enzyme activities of squalene metabolism were detected and analyzed.The results showed that there were differences in the number and content of volatile compounds in the tissue cultivation of PAL treated with different concentrations of trace elements.Compared with the untreated groud,4 mg/L Zn treatment and 1 mg/L,2 mg/L,4 mg/L La treatment had more volatile compounds.Zn and La treatment in-creased the content of alcohols and decreased the content of olefins.Zn and La treatment significantly reduced the con-tent of squalene.The treatment of 2 mg/L Zn increased the content ofβ-sitosterol,stigmasterol,ethyl palmitate,3-methyl-2-(5H)-furanone,2,3-dihydro-3,5-dihydroxy-6-methyl-4(h)-pyran-4-one,and decreased the content of squale-ne and phytol.The content of phytol in the leaves of 8 mg/L La treatment was the highest.The activities of squalene metabolism-related enzymes were changed in the process of tissue culture.Lanosterol synthase(LSS)activity and squalene epoxidase(SE)activity were stronger in the mixture,and squalene synthase(SQS)activity was stronger in adventitious roots.Different concentrations of trace elements had a certain effect on the activity of squalene-related enzymes.The content of squalene was positively correlated with LSS enzyme activity,SE enzyme activity and SQS enzyme activity in the PAL treated with different concentrations of Zn.The content of squalene in the tissue cultivation PAL treated with La was negatively correlated with LSS enzyme activity and SQS enzyme activity,and positively cor-related with SE enzyme activity.The results would enrich the relevant theoretical research on the regulation of trace elements on the volatile aroma compounds of PAL,and provided theoretical basis for improving the aroma quality of PAL.