Souquet J M, Labarbe B, Le Guernevé C, Cheynier V, Moutounet M
ISVV-INRA, Institut des Produits de la Vigne, Unité de Recherche Biopolymères et Arômes, 2 place Viala, 34060 Montpellier Cedex 2, France.
J Agric Food Chem. 2000 Apr;48(4):1076-80. doi: 10.1021/jf991171u.
Grape stems contain significant amounts of polyphenolic compounds, especially phenolic acids, flavonols, and flavanonols such as astilbin. The tannin content was characterized after the depolymerization reaction thiolysis. Tannins consisted of polymeric proanthocyanidins (up to 27 units) mainly consisting of (-)-epicatechin units along with smaller amounts of (+)-catechin, (-)-epicatechin gallate, and (-)-epigallocatechin. Flavanonols (astilbin) have been identified for the first time in stem and characterized by LC/MS and NMR. All phenolic compounds in grape stems were quantified by HPLC: quercetin 3-glucuronide was the most important, followed by catechin, caffeoyltartaric acid, and dihydroquercetin 3-rhamnoside (astilbin). Comparison was made of proanthocyanidin characteristics in different white and red grape varieties and also among parts of the cluster (skin, seed, and stem). Stem-condensed tannins were qualitatively intermediate between seed and skin but could not be differentiated between red and white varieties.
葡萄茎含有大量的多酚化合物，尤其是酚酸、黄酮醇和黄烷醇类，如落新妇苷。在解聚反应硫解后对单宁含量进行了表征。单宁由聚合原花青素（最多27个单元）组成，主要由（-）-表儿茶素单元以及少量的（+）-儿茶素、（-）-表儿茶素没食子酸酯和（-）-表没食子儿茶素组成。黄烷醇（落新妇苷）首次在葡萄茎中被鉴定出来，并通过液相色谱/质谱联用仪（LC/MS）和核磁共振（NMR）进行了表征。葡萄茎中的所有酚类化合物均通过高效液相色谱法（HPLC）进行定量：槲皮素3-葡萄糖醛酸苷是最重要的，其次是儿茶素、咖啡酰酒石酸和二氢槲皮素3-鼠李糖苷（落新妇苷）。对不同白葡萄和红葡萄品种以及果穗各部分（果皮、种子和茎）中原花青素的特性进行了比较。茎中的缩合单宁在性质上介于种子和果皮之间，但无法区分红葡萄品种和白葡萄品种。
