Variation of Chemical Composition of the Lipophilic Extracts from Yellow Birch (Betula alleghaniensis) Foliage

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• 作者：Jean-Michel Lavoie and Tatjana Stevanovic
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：2005
• 出版时间：June 15, 2005
• 年：2005
• 卷：53
• 期：12
• 页码：4747 - 4756
• 全文大小：229K
• 年卷期：v.53,no.12(June 15, 2005)
• ISSN：1520-5118

文摘

The occurrence of biologically active compounds identified for the first time in the lipophilic extractsof yellow birch (Betula alleghaniensis Britt.) foliage led to the quantification of the seasonal variationof their concentrations. Yellow birch foliage was collected from late June until late September 2003in two different regions of Quebec. The extraction yields using hexane as a solvent were determined,and the extracts were analyzed by GC-MS to identify their molecular composition. In terms of bothextraction yields and the concentration of the targeted molecules present in the extracts, mid-September has been determined as the best time to collect foliage samples. A total of 14 constituentswere identified in these extracts. This is the first report of the presence of all of these constituents inyellow birch foliage and of some of them in the genus Betula. The most important compounds identifiedin yellow birch foliage extracts are triterpene squalene and aliphatic hydrocarbon tetracosan, aliphaticalcohol phytol, fatty acids hexadecanoic and octadecanoic, pentacyclic triterpenes - and -amyrin,and phytosterol stigmast-5-en-3-ol.Keywords: Betula alleghaniensis; foliage; lipophilic extracts; seasonal variation; geographical variation;bioactive triterpenes and phytosterols