七种秋石斛鲜花挥发性成分差异性分析

Analysis on the volatile components in seven cultivars of Dendrobium

关键词:  秋石斛, 挥发性成分, SPME, GC-MS, 应用

Key words:  Dendrobium, floral volatiles, solid-phase microextraction, GC-MS, application

摘要:

为查明秋石斛不同品种关键赋香成分,利用固相微萃取(SPME)方法结合GC-MS技术,测定了秋石斛5个具香气的品种,即绿天使(Dendrobium Hand Green)、日出2号(Dendrobium Burana Sunrise No.2)、白花607(Dendrobium K. B. White 607)、紫背256(Dendrobium Blue Sapphine 256)、魅力(Dendrobium Burana Charming)以及2个不具香气的品种,即红牛(Dendrobium Red Bull)、三亚阳光(Dendrobium Sunya Sunshine)盛花期的花朵挥发性成分及其相对含量。结果表明:共鉴定出45种挥发性化合物,其中萜烯类34种、芳香族化合物8种、酯类3种,5种具香气的秋石斛花朵所含挥发性成分绝大部分都是萜烯类,萜烯类对秋石斛的花香起着重要的作用。通过比较发现,5种具香气秋石斛的主要赋香成分为3-蒈烯、芳樟醇、α-可巴烯和α-法尼烯,不同品种挥发性成分的组成和含量明显不同。绿天使和日出2号的主要香气成分是3-蒈烯,相对含量分别为59.343%和77.775%,但日出2号中的释放率约为绿天使的3倍; 白花607主要香气成分为3-蒈烯(29.170%)、α-可巴烯(17.660%)、芳樟醇(10.990%); 紫背256中α-法尼烯相对含量最高(42.310%); 魅力中主要香气成分是α-可巴烯(33.648%),邻苯二甲酸二异丁酯(13.866%)为其次。2个不具香气品种中鉴定出化合物较少,主要挥发性成分释放率较小; 红牛主要挥发性成分是胡莫柳酯(28.118%),三亚阳光是异丁子香酚(27.529%)。这些主要挥发性成分对不同品种秋石斛花的特有香味起决定性作用,且大部分已被广泛应用于香精香料,医药,日化等产品中。该研究结果为香型秋石斛产品开发及品种的培育提供了参考。

Abstract:

In order to understand the volatile constituents and relative contents in full-blown flower of five aroma cultivars(Dendrobium Hand Green, Dendrobium Burana Sunrise No.2, Dendrobium K. B. White 607, Dendrobium Blue Sapphine 256 and Dendrobium Burana Charming)and two non-fragrant cultivars(Dendrobium Red Bull, and Dendrobium Sunya Sunshine)of Dendrobium, were determined by solid-phase microextraction(SPME)and gas chromatography coupled with mass spectrometry(GC-MS). The results showed that there were 45 volatiles identified in seven cultivars, including 34 kinds of terpene, 8 kinds of aromatic and 3 kinds of esters. Five scented varieties volatile components mostly were terpene, and the terpene played an important role in aroma formation of Dendrobium. By comparison: main volatiles in five scented Dendrobium cultivars were 3-carene, linalool and α-copaene. Different species' volatiles and relative contents were significantly distinct. The major components of Dendrobium Hand Green and Dendrobium Burana Sunrise No.2 were 3-carene, the relative contents were 59.343% and 77.775%, but the emission rate of Dendrobium Burana Sunrise No.2 was about 3 times of Dendrobium Hand Green's; Dendrobium K. B. White 607's main volatiles was 3-carene(29.170%), α-copaene(17.660%), and linalool(10.990%); In Dendrobium Blue Sapphine 256's volatiles, the relative contents of α-farnesene was the highest(42.310%); the main volatiles in Dendrobium Burana Charming's were α-copaene(33.648%), followed by 1,2-benzenedicarboxylic acid, bis(2-methylpropyl)ester(13.866%). There were identified less volatiles in two non-fragrant cultivars, the main volatiles emission rates were also less; Dendrobium Red Bull's main volatile was homosalate(28.118%); the most important volatile was isoeugenol(27.529%)in Dendrobium Sunya Sunshine. The main volatile components played a decisive role of the scent in different varieties and most of them had been widely used in flavor, pharmaceutical, cosmetic and other products. Therefore, looking for the key aroma components in different cultivars would provide references for aroma cultivar breeding and products development of Dendrobium.