我国茶叶特别是发酵茶叶中含有许多有益真菌,其代谢产物具有抗菌、抗癌、降脂、降压的功能.目前,关于茶叶中真菌功能的研究很多,但在畜牧业中尚无相关应用研究.取湖南安化金花茯砖茶、天福南糯山熟饼、天福茗茶、天福白茶、安吉普洱茶、天福普洱、祁门红茶和金茯茶共8种茶叶进行真菌分离、纯化,共得到23株菌株,通过形态学和ITS基因序列的鉴定,共得到拟茎点霉菌1株,变色栓菌1株,枝状枝孢菌1株,黑曲霉2株,曲霉菌1株,冠突曲霉2株,阿姆斯特丹曲霉6株,棕曲霉2株,格孢菌1株,扩展青霉菌1株,拟盘多毛孢菌1株,球孢枝孢菌2株,变色曲霉2株.结果 为这些真菌的进一步研究和在生产实践中的应用提供了物质基础.并且将其中的优势菌属冠突散囊菌进行扩大培养,为后期的生产实践做好准备.

: Probiotic dark tea (PDT) is a novel kind of dark tea produced by fresh albino tea leaves and fermented with specific probiotics. Our study demonstrates that PDT can ameliorate high-fat diet-induced overweight and lipid metabolic disorders and shows no acute or subacute toxicity in Sprague-Dawley (SD) rats. Daily intragastric administration of 5% PDT infusion for 14 days caused no obvious effect on general physiological features and behaviors of rats. Oral administration of 1%, 2%, and 3% of PDT infusion for six weeks had no influence on the biochemistry and histopathology of rats' organs and blood, as well as the body weight and ratios of organ/body weight. To investigate its anti-obesity activity, SD rats were randomly divided into four groups, treated with normal diet + water (Group I), high-fat diet + water (Group II), high-fat diet + 3% traditional dark tea infusion (Group III), high-fat diet + 3% PDT infusion (Group IV). After six weeks, the body weight, serum total triacylglycerol (TG) and serum total cholesterol (TC) levels of rats in Group II were significantly increased and the high-density lipoprotein cholesterol (HDL) levels were significantly decreased compared with those in the other three groups. Both traditional dark tea and PDT treatment effectively counteracted the adverse effect of a high-fat diet in SD rats. These results suggest that PDT could be applied for the prevention of obesity, which ameliorates overweight and lipid metabolic disorders and which shows no acute or subacute toxicity.

为了探明白叶茶鲜叶制益生茶作为保健茶的毒理学安全性,以不同浓度的益生茶为原料,对SD大鼠同时进行急性和慢性毒性试验.急性毒性试验,清洁级SD大鼠随机分为对照组和试验组,试验组每天以5 mL/kg·BW浓度5%益生茶液灌胃,对照组灌服等量生理盐水,试验期为14 d,观察相关生理体征变化.慢性毒性试验,清洁级SD大鼠随机分为对照组和益生茶高、中、低剂量组共四组,益生茶对应各组自由饮用浓度分别为3%、2%和1%的茶液,对照组自由饮用蒸馏水,试验期6周,试验结束后,检测各组大鼠血液学和血液生化学指标及脏器系数变化.经口急性毒性试验中,益生茶对SD大鼠的食物利用率和生理体征无显著影响(P>0.05).慢性毒性试验中,益生茶各剂量组SD大鼠的体重、血液学、血液生化学指标值及各脏器的脏/体比值与对照组比较均无显著性差异(P>0.05).益生茶各组大鼠主要脏器在外观形态和组织学上均无异常变化.在本试验条件下,未发现明显毒性反应和病理变化,表明白叶茶鲜叶制益生茶对雄性大鼠基本无毒.