College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China.
Molecules. 2018 Jul 20;23(7):1796. doi: 10.3390/molecules23071796.
The relative overcapacity in China's tea-leaf production and the potential application of tea-leaf saponins in soil remediation encouraged in-depth developments and comprehensive utilizations of tea-leaf resources. Through variables optimizations using Box⁻Behnken designs for ultrasonic power, temperature as well as ultrasonic treatment time in ultrasonic-assisted water extraction and single-variable experiments for acetone-extraction solution ratio in acetone precipitation, a rapid and simple method was developed for preparing tea-leaf saponins. Tea-leaf saponins with the concentration of 3.832 ± 0.055 mg/mL and the purity of 76.5% ± 1.13% were acquired under the optimal values of 78 w, 60 °C, 20 min and 0.1 ratio of acetone-extraction solution. Both Fourier transform-infrared (FT-IR) spectra and ultraviolet (UV) spectra revealed slight composition differences between tea-leaf saponins and tea-seed saponins, while these differences were not reflected in the critical micelle concentration (CMC) and the surface tension of tea-leaf saponins and tea-seed saponins, indicating there was no need to distinguish them at the CMC. Further research attention on where tea-leaf saponins were in low concentrations is deserved to discover whether they had differences in comparison with tea-seed saponins, which was beneficial to apply them in the phytoremediation of contaminated soils.
中国茶叶产量相对过剩，茶叶皂素在土壤修复中的潜在应用，促使人们对茶叶资源进行了深入的开发和综合利用。通过超声辅助水提法的超声功率、温度和超声处理时间的 Box⁻Behnken 设计变量优化，以及丙酮沉淀法中丙酮提取液比的单变量实验，建立了一种快速、简单的茶叶皂素制备方法。在超声功率 78 W、温度 60°C、超声处理时间 20 min 和丙酮提取液比 0.1 的最佳条件下，获得了浓度为 3.832 ± 0.055 mg/mL、纯度为 76.5% ± 1.13%的茶叶皂素。傅里叶变换红外（FT-IR）光谱和紫外（UV）光谱表明，茶叶皂素和茶籽皂素的组成存在细微差异，但这些差异并未反映在茶叶皂素和茶籽皂素的临界胶束浓度（CMC）和表面张力上，表明在 CMC 处无需对其进行区分。进一步研究茶叶皂素在低浓度下的存在情况，以发现其与茶籽皂素是否存在差异，这有利于将其应用于污染土壤的植物修复中。
