Study On The Preparation And Bioactivity Of Rare Ginsenosides By Biotransformation

Panax notoginseng（Burk.）F.H.Chen is a kind of ginseng plant of Acanthopanax family,which is a traditional precious Chinese medicine in China.Panax notoginseng is rich in saponins,which are the main active components,and the rare ginsenosi des have higher pharmacological activity,but the content of rare ginsenosides in Panax notoginseng is very small or even does not exist,which needs to be transformed from the high content of the saponins in Panax notoginseng.The main purpose of this paper is to obtain rare Ginsenosides with higher activity from Panax notoginseng by biotransformation and study their biological activity.This paper consists of four chapters.The first chapter describes the research of obtaining rare ginsenosides by biotransformation in recent ten years,and summariz es the pharmacological activities of some rare ginsenosides obtained in this paper.The second chapter is about the separation and purification of fungi from different sourc es,and the biotransformation activity of the isolated fungi.The third chapter is about the bioactivity of the isolated fungi The biotransformation of total saponins of Panax notoginseng was studied and the transformed products were analyzed.In Chapter 4,the bacteriostatic and antitumor activities of the transformed products were studied.In the second chapter,89 fungi were isolated and purified from the soil and plants,and the biotransformation activity of total saponins of Panax notoginseng was screened.11 strains of fungi with saponin transforming activity were screened out by TLC and HPLC.Five strains with relatively strong activity of saponin transformati on were selected and identified and preserved.Through gene sequence comparison and morphological characteristics,it was preliminarily determined that the five highl y active strains were respectively Aspergillus niger,keratoderma,Trichoderma parrot,Aspergillus tabaci and Aspergillus fumigatus.In the third chapter,the biotransformation of total saponins from Panax notoginseng was studied.In order to verify the transformation ability of the active strain to the total saponins of notoginseng and determine whether there are rare ginsenosides in the transformation products,five strains with higher transformati on activity selected above were used to carry out large-scale culture of the biological transformation of the total saponins of notoginseng.The transformation product s were first extracted by water saturated n-butanol,and then purified by D101macroporous resin and silica gel column chroma tography to obtain the saponin rich maceration Through TLC and HPLC analysis,it was found that the active strai ns could transform total saponins of notoginseng and produce different rare ginsenosides.The rare ginsenosides produced by five different strains are as follows:（1）Sporotrichum nigrum:rare ginsenoside CK、20-（R/S）-Rg₂、20-（R/s）-Rg₃、etc.were obtained by fermentation;（2）Pyranopsis:rare ginsenoside Rh₄ was obtained by fermentation;（3）Trichoderma Parrot:rare ginsenoside 20-（R/S）-Rg₃、20-（R/S）-Rh₁、Rg₅、Rh₄、Rk₃and so on were obtained by fermentation;（4）Aspergillus tobinus:rare ginsenoside 20-（R/S）-Rg₃、20-（R）-Rg₂、Rk₃、20-（R/S）-Rh₁、Rh₄、Rg₅、etc.wer e obtained by fermentation.A high content of rare ginsenoside 20-（R）-Rh₁ was also isolated and identified from the transformation products of Aspergillus tobinus;（5）Aspergillus fumigatus:rare ginsenoside 20-（R/S）-Rg₂、Rk₃、20-（R/S）-Rg₃、20-（R/S）-Rh₁、etc.were obtained;The fourth chapter is about the biological activity of the transformed product s.The antibacterial activity and antitumor activity of the five fungi were tested.Plate growth inhibition method and Oxford cup method were used to test the antibacterial activity of the transformed products.Seven strains were select ed,including 4 species of Panax notoginseng and 3 species of human pathogens.The results showed that the inhibition rate of Trichoderma parrot transformation product s to four kinds of Panax notoginseng pathogenic fungi was the highest,which was much higher than that of other active strains,but the inhibition rate of all the transformati on products to four kinds of Panax notoginseng pathogenic fungi was not more than 50%;the inhibition effect of the transformation products of Aspergillus tobinus on Pseudomonas aeruginosa and Staphylococcus aureus was similar The results showed that the transformation products of all the active strains had no significant inhibit ory effect on Escherichia coli.We used ELISA methods to detect the change of ERK1/2 activity,so as to preliminarily detect the antitumor activity of the transformed products.The result s showed that the gradient elution products of six strains showed good cell activit y components,which generally contained 20-（R/S）-Rg₃、20-（R/S）-Rh₁、RK₃、Rh₄、Rg₅、C-K and so on.