泾阳茯茶中冠突散囊菌的鉴定及降脂作用研究

Study on identification and lipid-lowering effect of Eurotium cristatum in Fu tea from Jingyang county

中文关键词:  泾阳  冠突散囊菌  鉴定  肥胖模型  发花

英文关键词:Jingyang county  Eurotium cristatum  identification  obesity model  fungus growing

中文摘要:

      目的 探究陕西泾阳茯砖茶中冠突散囊菌的鉴定标志, 鉴定泾阳茯茶中的冠突散囊菌, 并研究其降脂作用。方法 从泾阳茯茶中分离筛选真菌, 观察其在3种不同培养基的生长特征, 结合形态学观察和真菌内源转录间隔区(internally transcribed spacer, ITS)基因序列同源性比对; 人工接种菌种至不同产区茶类中, 对接种至茶叶中菌种的形态学、扫描电镜(scan electron microscope, SEM)鉴定和接种后茶叶进行感官审评; 最后建立小鼠肥胖模型, 探讨回接冠突散囊菌后黑茶水浸提物对肥胖模型鼠的作用。结果 筛选分离得到的菌株(JY1)为冠突散囊菌(Eurotium cristatum, E.C.); 该菌在几种试验茶类均可以良好“发花”; 除红茶外, 其余茶样闭囊壳较饱满且子囊孢子的“赤道”周围存在较多小孔, 而红茶表现出以分生孢子为主; 接种后的散茶, 在香气, 汤色和滋味上均有不同程度变化; 与肥胖模型组相比较, 发花茶能显著抑制鼠体质量增长和Lee`s指数, 使血清总胆固醇(total cholesterol, TC)下降, 皮下脂肪细胞直径明显变小。结论 陕西泾阳茯茶中冠突散囊菌“赤道”周围存在较多小孔的电镜结果有可能作为陕西茯茶的特异性鉴定标志, 该菌可在黑茶, 红茶, 白茶, 绿茶上优势生长, 不同程度改变接种后的茶叶香气、汤色、滋味。回接冠突散囊菌后黑茶可降低血清总胆固醇水平, 同时有抑制脂肪细胞体积增大的作用, 且作用有一定时效性。

英文摘要:

      Objective To explore the identification markers of Sclerotinia sclerotiorum in the brick tea of Fuyang, Shaanxi Province, to identify the Eurotium cristatum in Fuyang tea, and to study its lipid-lowering effect. Methods The fungi were isolated and screened from Eurotium cristatum, and their growth characteristics in 3 different media were observed. The morphological observation and the homologous alignment of the fungal endogenous transcribed spacer (ITS) gene sequence were performed. The strain was inoculated into teas from different producing areas. The morphology of the strains inoculated into tea leaves was identified by scanning electron microscope (SEM). Sensory evaluation of inoculated tea leaves was conducted. Finally, a mouse obesity model was established to investigate the effect of black tea extract on the obese model mice after the return of Coronaria. Results Screening and isolated strain (JY1) was Eurotium cristatum (E.C.). The strain could be “flowered” in several test teas. Except for black tea, the rest of the tea-like closed capsules were fuller and there are many small holes around the “equator” of ascospores, while black tea was dominated by conidia. After inoculation, the loose tea had different degrees of change in aroma, soup color and taste. Compared with the obese model group, scented tea could significantly inhibit the growth of the body and the Lee`s index, which reduced the total cholesterol (TC) and the diameter of the subcutaneous fat cells. Conclusion The results of electron microscopy with more small pores around the “Equatorial” of Eurotium cristatum in Fuyang tea from Jingyang county may be used as a specific identification marker for Shaanxi Fu tea. The bacteria can grow on dark tea, black tea, white tea and green tea, which can change the aroma, soup color and taste of the tea after inoculation. Inoculated tea can reduce serum total cholesterol levels, inhibite the role of fat cell volume increase, and the effect has a time effect.