Studies On Microorganism Fermentation Of Rhodiola Sachalinensis Extract And Its Anti-fatigue Activity

Objective:To investigate the technological conditions of Lactic acid bacteria fermentation by using Rhodiola sachalinensis as fermentation materials and salidroside as index. Screen of probiotic bacteria on microbial fermentation to increase the content of main active component in Rhodiola sachalinensis, salidroside, through the optimization of fermentation conditions. The content measuring method taken in this paper is HPLC, and anti-fatigue activity of fermented Rhodiola sachalinensis was investigated. Through the antioxidant system arid energy metabolism system to study the anti-fatigue mechanism, provide experimental basis for the analysis of the efficacy of Rhodiola sachalinensis and for the development of anti-fatigue drugs.Methods:Activate and juvenate fermentation strains, determine the pH of fermentation liquor after inoculation and the number of living bacterium to know the growth conditions of fermentation strains, using diazo salt colorimetry pliminarily determine the content of salidroside, screen out the strain which can increase the salidroside content. Through single-factor test, the effects of filling quantity, inoculum size, initial pH, culture time, culture temperature, carbon sourceon and nitrogen source on salidroside yield by Lactic acid bacteria fermentation we primarily discussed. After single factor experiment, orthogonal testing design was adopted by choosing filling quantity, inoculum size, initial pH and culture time four factors as index. Then the contents of fermented Rhodiola sachalinensis (FR) and Rhodiola sachalinensis extract (RE) after enrichment and feze drying process we tested with HPLC. The separation was performed on a Kroasil C18 (4.6 mmx250 mm,5 μm), Methyl Cyanides-water gradient elution, the mobile phase was at a flow rate of 1.0 ml/min. The detection wavelength was 276 nm. Column temperatu was 25℃. The sample size was 20 μL. Finally, the anti-fatigue activity of fermented Rhodiola sachalinensis was studied:108 mate mice were randomly divided into there groups:FR (fermented Rhodiola sachalinensis,1.5 g/kg.d), RE (Rhodiola sachalinensis extract,1.5 g/kg.d), CG (control group). Samples were intragastric administed into mice once per day with 0.2 mL/10 g for 15 days. Then the following indicators were determinated. Changes of the body weight of the mice were observed during initial, intermediate and terminal stages of the test. The anti-fatigue activity was evaluated using weight-loaded swimming test, SOD, MDA and GSH-PX in hepatic tissue of weight-loaded swimming test, the determination of BUN, hepatic glycogen and LD contents, along with the activity of LDH.Results:Rhodiola sachalinensis fermentation strain was Lactobacillus acidophilus (L1). The optimum conditions of Lactic acid bacteria fermentation by using Rhodiola sachalinensis as fermentation materials to yield salidroside were as follows:Rhodiola rosea powder mixed with water 1:15, then put into peptone 1%, glucose 2%,6.0 of initial pH, inoculate 10% seed liquid,37℃ of culture temperature for 48 h. The results showed that the contents of slidroside were fermented Rhodiola sachalinensis 2.39%, Rhodiola sachalinensis extract 1.61%. In optimized fermentation conditions, the content of salidroside incased by 48.45%. Both FR and RE had no adverse effects on growth development of mice. Both FR and RE could extend exhausting swimming time of the mice. The anti-fatigue effect of FR was better than RE with the same dose. FR could improve the activity of antioxidant enzyme (SOD, GSH-PX) and decreased the content of MDA. FR extmely reduced the content of BUN. FR had inapparent effect on the content of hepatic glycogen. FR could improve the activity of LDH, and eliminate the LD in blood effectively.Conclusion:1. Fermentation strain and cultivate condition could affect the growth of Lactic acid bacteria and Rhodiola sachalinensis fermentation yield markably. In optimized fermentation conditions, the content of salidroside increased by 48.45%.2. Diazonium salt colorimetry could be taken by the pliminary determination of salidroside content, larger than HPLC chromatography determination result, but because of the method was simple and easy, so it can be used as the sieve method at the beginning of the fermentation process, HPLC chromatography as a content determination method in this paper has the advantages of rapid and accurate.3. Fermented Rhodiola sachalinensis has good anti-fatigue and anti-oxidant activity, its mechanism of action remains to be further in-depth study. So research and develop rhodiola yeast health foods and medicines has a certain value.