Study On The Efficacious Material Basis Of Aloe And The Method Of Its Quality Assessment

This study was made in 5 fundamental steps as follows:1. Twenty eight aloe samples were collected from different origins and identified by an expert in pharmacognosy - 19 as Aloe barbadensis Miller, 5 as Aloe vera L. var. chinensis (Haw.) Berger and 4 as Aloe arborescens Miller. After step 2. had been carried out, based on the HPLC data obtained, a hierarchical cluster analysis and a stepwise discrimination analysis were performed on the 28 aloe samples. The results obtained were all the same to the groups into which the 28 aloe samples were classified by the expert with traditional methods.2. Two high-performance liquid chromatograms, one for the water and the other for the chloroform extract of each aloe sample, were drawn under two different HPLC conditions. The two chromatograms form a chromatographic fingerprint of each aloe sample.3. Pharmacological experiments of defecation on rats with 28 different portions of aloe extract were carried out; the software package SPSS with programs of correlation and stepwise regression was adopted;the programs were instructed to perform a correlation analysis and a stepwise regression analysis of "defecation effect vs. chromatographic data" respectively and independently with a result that the data obtained in the two statistical methods are consistent and mutually supporting; and 4 efficacious constituents revealed by 4 HPLC peaks - X27, X31, X38 and X52- were recognized and statistically inferred at the significance level a<0.1 %. Such a chromatogram may be called distinctive chromatogram and used to identify aloe sample. The HPLC, TLC and MS data of the efficacious constituent revealed by X31, one of the 4 HPLC peaks, was confirmed as barbaloin, a known compound with defecation effect.4. Owing to the representativeness in efficacy of barbaloin, its being known on molecular structure and ease of obtaining, the reference standard of it was used to develop a HPLC method to assay the content of the 28 aloe samples. The average recovery of the assay is 98.8 % and its RSD is 1.0%.5. The pharmacokinetic experiments of efficacious constituents barbaloin and aloinoside B were conducted to clarify the action of aloinoside B and barbaloin and their relationship in metabolism in gastrointestinal tracts of rats; and the orthogonal array OA9 (34) was used to arrange trials for the optimization of extraction conditions of aloe raw material so that the positive results of this study would be more easily adopted in the modernized production of aloe.The first 3 steps are applicable in principle to the determination of efficacious material basis of other Chinese medicines. The 3 steps have been summarized as a statistical methodology, step 3 - multivariate chemical pattern recognition - being the core.