霍山石斛药理学研究及其在保健食品中的应用进展

为了探究霍山石斛（Dendrobium huoshanense，DH）与祁门红茶（Keemun black tea，KBT）协同预防免疫力降低的效果，以石斛多糖提取率和红茶多酚提取率为指标，通过单因素实验和正交试验对霍山石斛和祁门红茶的料液比、提取时间和提取次数因素进行研究，分别优化霍山石斛与祁门红茶的提取工艺，再通过对RAW264.7细胞的毒性试验和吞噬活力试验确定红茶与石斛的最佳配比。结果表明，石斛多糖的最佳提取条件为：料液比1:80（g/mL），提取时间80 min，提取次数4次；茶多酚的最佳提取条件为：料液比1:80（g/mL），提取时间25 min，提取次数5次。通过观察不同比例的混合物对巨噬细胞的影响，确定红茶与石斛的配比。体外试验结果表明，75%红茶和25%石斛配比的祁门红茶和霍山石斛提取混合物（Keemun black tea and Dendrobium huoshanense，KTDH）具有最佳的免疫增强效果。体内试验结果表明KTDH高剂量组对小鼠由于免疫抑制而显著上调作用的细胞因子IL-2和IL-6水平有显著回调作用（P<0.01）。综上所述，霍山石斛与祁门红茶可协同增强免疫力并预防免疫力下降，可为霍山石斛和祁门红茶的开发应用途径提供新思路。

Immunoregulatory activities of Dendrobium huoshanense polysaccharides in mouse intestine,spleen and liver

To explore the synergisic effect of DH (Dendrobium huoshanense) and KBT (Keemun black tea) on preventing immunity reduction. The solid-liquid ratio, extraction time and extraction times of DH and KBT were studied by single factor test and orthogonal test with the extraction rate of Dendrobium polysaccharide and black tea polyphenols as indexes, the extraction techniques of DH and Keemun black tea were optimized respectively. The optimal ratio of KBT and DH was determined by toxicity test and phagocytosis test on RAW264.7 cells. The results showed that the optimum extraction conditions of DH polysaccharide were as follows: The ratio of material to liquid was 1:80 (g/mL), the extraction time was 80 min, and the extraction times were 4 times. The optimum extraction conditions of KBT polyphenols were as follows: The ratio of material to liquid was 1:80 (g/mL), the extraction time was 25 min, and the extraction times were 5 times. The ratio of KBT to DH was determined by observing the effect of different proportions of the mixture on macrophages. The results of the in vitro experiment showed that the extract mixture of 75% KBT and 25% DH had the best immune-enhancing effect. The results of the in vivo test showed that the high-dose group of KTDH could significantly reduce the changes of levels of cytokines IL-2 and IL-6 due to immunosuppression in mice (P<0.01). To sum up, DH and KBT can synergistically enhance immunity and prevent immune decline, which can provide new ideas for the development and application of DH and KBT.