Abstract:
Unlike all other caffeinated plants, guayusa (Ilex guayusa Loes.) and maté (Ilex paraguariensis A. St. Hill) contain high amounts of pentacyclic triterpenoid acids and alcohols. A phytochemical investigation on these plants revealed a similar triterpenoid profile and a content of ursolic acid (0.7-1%) and amyrin esters (up to 0.5%), quite unusual for dietary plants. The major constituent of the amyrin complex from both plants is α-amyrin palmitate (2a), accompanied by lower amounts of its corresponding palmitoleate (2b) and by the corresponding constitutional isomers from the β-series (3a and 3b, respectively). Ursolic acid (1) was identified as the responsible for the activity of maté and guayusa extracts in the activation of TGR5, a nuclear receptor of relevance for the prevention and management of diabetes and metabolic syndrome because of its involvement in the regulation of energy expenditure and insulin sensitivity.
摘要:
不像所有其他含咖啡因的植物,guayusa(IlexguayusaLoes。)和maté(IlexparaguariensisA.St.Hill)含有大量的五环三萜酸和醇。对这些植物的植物化学研究显示出相似的三萜类化合物分布和熊果酸(0.7-1%)和胺苷酯(高达0.5%)的含量,对于膳食植物来说很不寻常。两种植物的amyrin复合物的主要成分是α-amyrin棕榈酸酯(2a),伴随着较低量的其相应的棕榈油酸酯(2b)和相应的组成异构体从β系列(3a和3b,分别)。熊果酸(1)被确定为负责激活TGR5的活性,TGR5是一种与预防和管理糖尿病和代谢综合征相关的核受体,因为它参与了能量消耗和胰岛素敏感性的调节。