Systematic Quality Evaluation Of Tianma From Six Main Producingregions And Study On The Tianma Standard Decoction Pieces

Gastrodia elata(Tianma)is the dried rhizome of Gastrodia elata Blume,which was initially recorded in Shen Nong’s Herbal Classic,and considered as a top grade herbal medicine.It contains phenols,organic acids,polysaccharides and other chemical constituents,which can be used for the treatment of convulsion,inflammation,epilepsy,depression,etc.With the development of cultivation technology of Tianma,the planting areas have been expanded rapidly.Currently,Shanxi,Sichuan,Guizhou,Yunnan provinces become main producing areas of Tianma.Besides,it is distributed in Gansu,Jiangsu,Anhui,Zhejiang,Hubei,and Hunan provinces.Many studies on the quality of Tianma have been reported,but there are some problems such as incomplete regions and insufficient sample amount,and systematic evaluation for its quality has not been studied.Therefore,the quality of 79 batches of Tianma collected from Shanxi,Yunnan,Guizhou,Anhui,Zhejiang and Hubei provinces was systematically evaluated.In addition,standard decoction pieces were also the hotspot of current research,the processing and homogenization technologies of Tianma decoction pieces were also investigated.Meanwhile,crude and purified polysaccharides were obtained from Tianma,and their basic properties and immunological activities were studied.At first,the quality of 79 batches of Tianma was systematically evaluated by classical quality evaluation,multi-component quantitative and fingerprints analyses.It was found that the quality of these samples were qualified.Besides,a reliable HPLC-PDA analytical method was established for the determination of six compounds in Tianma and the establishment of chromatographic fingerprints.The results of chromatographic fingerprints indicated that the quality of Tianma from the same region was similar.The types of compounds in the same grade of Tianma from different regions were similar,but there were difference in the contents of components.According to six compounds contents,Tianma were divided into three groups by hierarchical cluster and principal component analyses.The first group contained Tianma from Anhui province,the total content of six components was between 1.67 and 2.41 %.The second group included Tianma from Yunnan and Shanxi provinces and the content was in the range of 1.19-2.13 %.The third group consisted of Tianma from Guizhou,Zhejiang and Hubei provinces,the content ranged from 2.38 % to 3.03 %.The correlation analysis results showed that Tianma from Guizhou,Yunnan and Shanxi provinces contained higher content of p-hydroxybenzyl alcohol was more suitable as antioxidants,and samples from Anhui province with high level of gastrodin can be used as hypoglycemic agents.Moreover,the grade quality standard of Tianma was established based on appearance characteristics and intrinsic quality.The first grade of Tianma was less than 24 per kilogram,and the contents of extract,gastrodin and p-hydroxybenzyl alcohol,as well as six components were more than 17.0 %,0.30 %,and 1.70 %,respectively.The second grade of Tianma was less than 42 per kilogram,and other indicators were the same as the first grade.The third grade of Tianma was less than 90 per kilogram,the contents of extract,gastrodin and p-hydroxybenzyl alcohol met the requirements of Chinese Pharmacopoeia,and the total contents of six components were not required.The fourth grade of Tianma was more than 90 per kilogram,and other indicators were the same as the third grade.Meanwhile,the processing technologies were optimized by orthogonal tests with the content of gastrodin and p-hydroxybenzyl alcohol and total polysaccharide content as indicators.The optimal steaming processing technology was that Tianma was soaked for 3 h,steamed for 3 h,sliced and dried at 40 °C.The optimal moistening processing technology was that Tianma was soaked for 54 h,moistened for 22 h,sliced and dried at 60 °C.Furthermore,the homogenization technology was optimized by orthogonal test with the flour yield and the content of gastrodin and p-hydroxybenzyl alcohol as indicators.The optimal homogenization technology was 15 s for single crushing time,three times for crushing times and 3/4 for the proportion of feed amount to the volume of the pulverizer.The verification experiments proved that the optimal technologies were stable and feasible.Finally,crude and purified polysaccharides were obtained from Tianma.The molecular weight of purified polysaccharide was lower than crude polysaccharide,and glucose was the predominant monosaccharide in these two polysaccharides.In addition,both of them possessed immunological activities and were not toxic to RAW 264.7 cells.These results demonstrated that Tianma polysaccharides could serve as immunological adjuvants.