Bioactive metabolites in of Ginkgo biloba leaves: variations by seasonal, meteorological and soil

Abstract Ginkgo biloba is a traditional Chinese herbal medicine containing multiple components that contribute to its notable bioactivities. Variations of seasonal, meteorological and planting soil on the phytochemicals contents in G. biloba leaves due to the effects of growth meteorological and soil parameters were investigated in this study. The leaves of G. biloba were collected from different months and place in Zhejiang province, the contents of flavones (quercetin, kaempferol and isorhamnetin) and terpene lactones (bilobalide, ginkgolides A, B and C) were quantified by high performance liquid chromatography (HPLC) and the evaporative light scattering detector (ELSD) method. The established methods were validated with good linearity, precision, repeatability, stability, and recovery. Comprehensive analysis suggested the proper harvest time for G. biloba was in October of Zhejiang province. The result of correlation analysis with meteorological factors shows that the temperature and precipitation have non-significant effect on the main components of G. biloba. In addition, the type and content (Mn and Zn) of the soil showed significantly effect on the content of flavonoids and terpene lactones. This study enriched the knowledge on the development and utilization value of the G. biloba leaves and was useful for determining the optimal harvest time and growing condition.

摘要：银杏（Ginkgo biloba）是一种传统中草药，其含有的多种活性成分赋予其显著的生物活性。本研究围绕生长气象参数与土壤参数的作用，探究了季节、气象及种植土壤条件对银杏叶中植物化学成分含量的影响差异。研究人员从浙江省不同采样月份与地点收集银杏叶样本，采用高效液相色谱法（high performance liquid chromatography, HPLC）结合蒸发光散射检测器（evaporative light scattering detector, ELSD），对黄酮类成分（flavones）中的槲皮素（quercetin）、山奈酚（kaempferol）、异鼠李素（isorhamnetin），以及萜内酯类成分（terpene lactones）中的白果内酯（bilobalide）、银杏内酯A（ginkgolides A）、银杏内酯B（ginkgolides B）与银杏内酯C（ginkgolides C）的含量进行了定量分析。本研究建立的分析方法经方法学验证，展现出良好的线性关系、精密度、重复性、稳定性及回收率。综合分析结果表明，浙江省境内银杏叶的适宜采收期为10月。气象因子相关性分析结果显示，气温与降水量对银杏叶主要成分无显著性影响。此外，土壤类型及其锰（manganese, Mn）、锌（zinc, Zn）含量对黄酮类与萜内酯类成分的含量具有显著影响。本研究丰富了银杏叶开发利用价值的相关认知，可为确定最佳采收期与种植条件提供理论参考。