三七总皂苷发酵工艺优化及发酵前后免疫调节作用研究

Optimization of fermentation technology of Panax notoginseng saponins and immunomodulatory effects before and after fermentation

目的:优化三七总皂苷发酵制备工艺,并比较发酵前后免疫活性。方法:在单因素试验基础上,采用响应面分析法优化三七总皂苷的发酵工艺,考察培养基pH值、发酵时间、发酵温度和植物乳杆菌菌液接种量4个因素对人参皂苷Rh1、Rg3和Compound K(CK)的含量的影响。皮下注射乙酰苯肼和环磷酰胺建立免疫抑制模型,检测不同给药组的大鼠体质量、胸腺和脾脏系数;采用酶联免疫吸附法检测血清中TNF-α、IFN-γ、IL-6和IL-10的水平,对比发酵前后三七总皂苷对免疫抑制大鼠的调节作用。结果:三七发酵总皂苷最佳制备工艺为:培养基pH 7.0、发酵时间3.2 d、发酵温度37.6℃和植物乳杆菌菌液接种量3.1%,发酵后三七总皂苷含量为2.42 mg·g^(-1)。药理试验结果显示:发酵前后的三七总皂苷均能增加免疫抑制大鼠胸腺指数和脾脏指数,提高血清中炎症因子TNF-α、IFN-γ、IL-6和IL-10水平,且三七发酵总皂苷的免疫调节作用优于发酵前三七总皂苷。结论:三七总皂苷在发酵后人参皂苷Rh1、Rg3和CK含量明显增多,免疫调节作用增强。

OBJECTIVE To optimize the fermentation technique of Panax notoginseng saponins and compare the immune activity of saponins before and after fermentation.METHODS Fermentation process of saponins was optimized with a response surface methodology based upon a single factor experiment where medium pH value,fermentation time,fermentation temperature and amount of inoculation of Lactobacillus plantarum were influencing factors.And total contents of ginsenosides Rh1,Rg3 and Compound K(CK)were response values.An immunosuppressive model was established by an intradermal injection of acetylphenylhydrazine and cyclophosphamide.Thymic and splenic indices were calculated by weighting body,thymus and spleen.Serum levels of tumor necrosis factor-alpha(TNF-α),interferon-gamma(IFN-γ),interferon-6(IL-6)and interferon-10(IL-10)were detected by enzyme-linked immunosorbent assay(ELISA).And improvement effects of saponins before and after fermentation on immunosuppressed rats were evaluated with the above indices.RESULTS The optimal fermentation conditions were as follows:pH 7.0,fermentation time 3.2 days,fermentation temperature 37.6℃and inoculation amount of L.plantarum liquid 3.1%.Three parallel experiments were performed under optimal conditions with a total saponin level of 2.42 mg·g^(–1).PNS before and after fermentation could boost thymic index and splenic index of immunosuppressed rats and elevate the serum levels of TNF-α,IFN-γ,IL-6 and IL-10.Also immune activity of PNS post-fermentation was higher than that of PNS pre-fermentation.CONCLUSION The levels of ginsenoside Rh1,Rg3 and CK spike markedly in fermented saponins and immunomodulatory effects are significantly enhanced.