Zhou Tao, Luo Chun-Mei, Huang Zhi-Fang, Liu Yu-Hong, Liu Yun-Hua, Chen Yan, Tang Yi-Na, Yi Jin-Hai
Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica,Sichuan Academy of Chinese Medicine Sciences Chengdu 610041, China School of Pharmacy, Southwest Medical University Luzhou 646000, China.
Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica,Sichuan Academy of Chinese Medicine Sciences Chengdu 610041, China.
Zhongguo Zhong Yao Za Zhi. 2020 Mar;45(5):1090-1096. doi: 10.19540/j.cnki.cjcmm.20191221.308.
There were significant differences in phenolic acid content between fresh and dried Salvia miltiorrhiza before and after drying. That is to say, the content of phenolic acid in S. miltiorrhiza significantly increased with the increase of dehydration during the drying process.In order to investigate the differences and transformation of free and bound phenolic acids before and after the drying process of S.miltiorrhiza, we studied hydrolysis method, hydrolysates and hydrolysis regularity of phenolic acids in S.miltiorrhiza. UPLC method was used to determine four main hydrolysates of bound phenolic acids, namely danshensu, caffeic acid dimer(SMND-309), caffeic acid, przewalskinic acid A(prolithosperic acid), and three main free phenolic acids in S.miltiorrhiza, namely rosmarinic acid, lithospermic acid, salvianolic acid B. The results of the acid-base hydrolysis experiment of salvianolic acid showed that the alkaline hydrolysis effect was significantly better than acid hydrolysis. The optimal alkaline hydrolysis condition was hydrolysis at 70 ℃ for 4 h with 2 mol·L~(-1) NaOH solution containing 1% ascorbic acid(Vit C). The hydrolysates of free phenolic acids were the same with the hydrolysates of bound phenolic acids. Fresh S.miltiorrhiza contains a low level of free phenolic acids and a high level of bound phenolic acids, which were exactly opposite to dried S.miltiorrhiza. It was suggested that a large amount of bound phenolic acids was accumulated during the growth of S.miltiorrhiza. These bound phenolic acids were coupled with polysaccharides on the cytoderm through ester bonds to form insoluble phenolic acids, which was not easy to be detected by conventional methods. However, during drying and dehydration processes, the bound phenolic acids were converted to a large amount of free phenolic acids under the action of the relevant enzyme.
新鲜和干燥的丹参在干燥前后酚酸含量存在显著差异。也就是说，丹参中酚酸含量在干燥过程中随着脱水程度的增加而显著增加。为了研究丹参干燥前后游离和结合酚酸的差异及转化情况，我们研究了丹参中酚酸的水解方法、水解产物及水解规律。采用超高效液相色谱法测定结合酚酸的四种主要水解产物，即丹酚酸、咖啡酸二聚体（SMND - 309）、咖啡酸、紫草酸A（原儿茶酸），以及丹参中三种主要游离酚酸，即迷迭香酸、紫草酸、丹酚酸B。丹酚酸的酸碱水解实验结果表明，碱性水解效果明显优于酸性水解。最佳碱性水解条件为：在70℃下用含1%抗坏血酸（维生素C）的2 mol·L⁻¹氢氧化钠溶液水解4 h。游离酚酸的水解产物与结合酚酸的水解产物相同。新鲜丹参中游离酚酸含量低，结合酚酸含量高，这与干燥后的丹参情况正好相反。这表明丹参在生长过程中积累了大量的结合酚酸。这些结合酚酸通过酯键与细胞壁上的多糖结合形成不溶性酚酸，用常规方法不易检测到。然而，在干燥和脱水过程中，结合酚酸在相关酶的作用下转化为大量游离酚酸。
