黄芪渣中国拟青霉固体培养及发酵产物分析

以黄芪渣培养冬虫夏草菌——中国拟青霉,研究固体发酵条件及发酵产物成分含量变化。结果表明:固体发酵的温度为20℃,培养基含水量60%,pH自然,氧气充足,无需光照条件下适宜生长,发酵时间为45 d。虫草黄芪粉粗多糖含量为10.32%,比黄芪废弃物中粗多糖含量增加47%;甘露醇含量为2.38%,比黄芪废弃物中甘露醇含量提高11.5倍;水溶蛋白含量为1.72%,比黄芪废弃物高2.80倍。     

超临界CO2萃取香椿叶总黄酮

正交实验法优化了超临界CO2萃取香椿叶总黄酮的工艺。在原料50 g,分离室Ⅰ温度35℃、压力7 MPa;分离室Ⅱ温度35℃、压力与储罐平衡条件下,超临界CO2萃取香椿叶中总黄酮的最佳工艺条件为:萃取压力30MPa,萃取温度45℃,萃取时间2.5 h,夹带剂用量为3 mL/g原料,CO2流量35 L/h,提取5次,前2次用无水乙醇、后3次用体积分数为85%的乙醇做夹带剂。在此条件下1 g香椿叶中提取的总黄酮质量为8.8369 mg,总萃取率为51.06%,提取物以总黄酮计的清除2,2-二苯代苦味酰基苯肼基(DPPH)自由基的IC50为5.080 g.g-1。     

Molecular evidence for maternal inheritance of the chloroplast genome in tea,Camellia sinensis (L.) O. Kuntze

BACKGROUND: Tea is the most consumed beverage worldwide after water. Yet very little is known about the genetics of tea in comparison with other crop species. Here we have taken advantage of the polymorphic nature of microsatellite DNA to investigate the mode of chloroplast inheritance in tea, Camellia sinensis (L.) O. Kuntze. This is important for the correct interpretation of phylogeny and introgression data as well as assessing the suitability of chloroplast transformation as a means for transgene containment in tea. RESULTS: The study was based on six Japanese tea cultivars, namely Aj2, CK23, Hatsumomiji, Nka05, Yamanoibuki and Kanayamidori used to generate four informative families. The parental pairs in the crosses differed at a single chlroroplast locus with respect to an imperfect microsatellite repeat of 16 nucleotide bases. In agreement with earlier cytological studies, all 61 progeny displayed a cpDNA profile that was consistent with the maternal inheritance of chloroplasts in tea. CONCLUSIONS: The data generated here provide the first molecular evidence of the plastid inheritance in tea. However, we suggest that additional families and polymorphic markers be screened for increasing the confidence in the observed maternal inheritance of chloroplasts in this important crop species. Copyright © 2011 Society of Chemical Industry     

A review of recent studies in China on the possible beneficial health effects of tea

Tea is one of the most heavily consumed beverages in the world. The relationship between tea drinking and human health is becoming a subject of intense study by scientists throughout the world. In this paper, we first provide a comprehensive analysis of the medical literature on tea published in China during the past 20 years, and then highlight some recent studies in China on the relationship between tea and several human diseases. During the period 1982–2002, 691 research papers related to tea and health have been published in 290 Chinese journals. These studies showed that tea and tea constituents have various biological activities and suggested that tea drinking might be beneficial to human health. Tea has potential in the prevention or adjuvant treatment of several diseases including cancer, cardiovascular diseases and obesity. The trend and future direction in medical research on tea in China are also briefly discussed.     

Application of chemical composition and infusion colour difference analysis to quality estimation of jasmine-scented tea

Infusion chemical composition, colour difference indicators and volatile constituents of seventeen jasmine‐scented tea samples and their correlation with sensory total quality score given by tea‐tasting panel were studied by techniques of HPLC, colour difference metre and gas chromatograph. Spearman's linear correlation analysis showed that concentration of nitrogen, caffeine, catechin, epicatechin, catechin gallate, total catechins, terpineol, nerol and infusion light‐black indicator ΔL, yellow‐blue indicator Δb, total colour difference indicator ΔE were significantly correlated with sensory total quality score, respectively. Regression of the total quality score upon twelve components extracted from thirty‐six tested indicators by principal component analysis could properly estimate total quality score of two jasmine‐scented tea samples which were not included in the seventeen samples used to construct the regression model.     

当归多糖对DPN大鼠TLR4/MyD88/NF-κB通路抑制影响

目的: 分析当归多糖对糖尿病神经病变（DPN）大鼠TLR4/MyD88/NF-κB通路抑制影响。方法: 选取SPF级Wistar雄性大鼠105只,随机选取15只作为正常组,剩余90只大鼠制备DPN模型,成功造模75只,随机分成5组,模型组、当归多糖低、中、高剂量组和阳性对照组,每组15只。模型组和正常组大鼠采用2 mL/100 g生理盐水灌胃,当归多糖低、中、高剂量组大鼠给予当归多糖药液灌胃,阳性对照组给予弥可保+二甲双胍溶液灌胃,每日给药体积均为2 mL/100 g。每天1次,连续灌胃10 d。给药3、10 d后检测大鼠机械缩足反应阈值（PWT）、热缩足反射潜伏期（PWL）,末次给药后检测大鼠空腹血糖、血清丙二醛（MDA）、超氧化物歧化酶（SOD）、过氧化氢酶（CAT）活性、谷胱甘肽过氧化物酶（GSH-Px）、白细胞介素-6（IL-6）、髓鞘碱性蛋白（MBP）、TNF-α及C反应蛋白（CRP）含量,检测大鼠运动神经传导速度（MNCV）、感觉神经传导速度（SNCV）,大鼠坐骨神经内核因子-κB（NF-κB） mRNA、髓样分子因子88（MyD88） mRNA及Toll样受体4（TLR4） mRNA表达。结果: 模型组及当归多糖低剂量组大鼠空腹血糖、MDA含量显著高于正常组,CAT、SOD及GSH-Px含量显著低于正常组,当归多糖中、高剂量组大鼠空腹血糖、MDA含量显著低于模型组、阳性对照组,CAT、SOD及GSH-Px含量显著高于模型组、阳性对照组,差异有统计学意义（P＜0.05）;模型组、当归多糖低剂量组大鼠血清IL-6、MBP、TNF-α及CRP含量均显著高于正常组,当归多糖中、高剂量组大鼠血清IL-6、MBP、TNF-α及CRP含量均显著低于模型组、阳性对照组,差异有统计学意义（P＜0.05）;模型组、当归多糖低剂量组大鼠NF-κB mRNA、MyD88 mRNA及TLR4 mRNA表达量均显著高于正常组,当归多糖中、高剂量组大鼠NF-κB mRNA、MyD88 mRNA及TLR4 mRNA表达量均显著低于模型组、阳性对照组,差异有统计学意义（P＜0.05）。结论: 当归多糖可显著改善DPN大鼠的周围神经损伤状态,促进神经传导的恢复,其机制可能与阻断TLR4/MyD88/NF-κB信号路径的转导,降低炎性因子水平,减轻神经的氧化应激损伤有关。     

当归、甘草、芦荟美白护肤霜的研制

以常见的中草药当归、甘草、芦荟为初始原料,从中提取出有效成分作为美白护肤霜的天然添加剂,研制成水包油型的膏霜类高级化妆品,探讨了配制工艺对美白护肤霜效果的影响,并对美白护肤霜的性能进行了评价,证明产品具有良好的美白功效,质量符合要求。     

我国4省养殖中华绒螯蟹中甲基汞的污染特征及健康风险评价

目的 探讨我国主产区养殖的中华绒螯蟹(Eriocheir sinensis)中甲基汞(methylmercury,MeHg)累积情况和食用安全风险。方法 利用高效液相色谱-原子荧光联用法(high performance liquid chromatography and atomic fluorescence spectrometry,HPLC-AFS)分析了湖北、安徽、江苏、辽宁4省14个地市生产的135份人工养殖中华绒螯蟹的MeHg含量。采用单因子污染指数(single-element pollution indices,Pi)、每周可耐受摄入量(provisional tolerable weekly intake,PTWI)和目标危害商值(target hazard quotient,THQ)法分别评价了其污染程度和食用安全性。结果 MeHg的检出率达91.1%,含量范围为ND(未检出)～133.1μg/kg,所有样品的MeHg含量均未超出国家标准限量值。膳食暴露评估结果表明成人每周摄入量(estimated weekly intakes,EWI)低于联合国粮农组织和世界卫生组织下的联合专家委员会(Joint Food and Agriculture Organization /World Health Organization Expert Committee on Food Additives, JECFA)推荐的食品添加剂的PTWI。结论 所有养殖中华绒螯蟹样品的THQ值均小于1,介于0.009~0.288之间,表明摄入这些地区养殖中华绒螯蟹的MeHg暴露风险较低。     

物理处理鱼体内华支睾吸虫囊蚴感染兔实验观察

为研究钴-60辐照和-18℃～-20℃冷冻对鱼肉中华支睾吸虫囊蚴感染的影响，设立A、B2个实验组。一组用0．05、0．10、0．15、0．20、0．25kGy钴-60对含华支睾吸虫囊蚴的鱼肉进行辐照；另一组将感染了华支睾吸虫囊蚴的鱼肉于-18～-20℃冷冻3、7、14、2l、28d。用两组处理过囊蚴的鱼肉灌喂家兔，用粪检虫卵和解剖动物检查虫体的方法判定结果。囊蚴感染家兔45d后解剖，0．15、0．20、0．25kGy组及冷冻组鱼肉饲喂的动物内均未找到华支睾吸虫成虫、童虫、和虫卵。肝胆器官未见病变。鱼肉中的华支睾吸虫囊蚴经钴-600．15kGv以上剂量辐照或存放于-18℃～-20℃冷冻3d以上，便失去感染力。     

Understanding different regulatory mechanisms of proteinaceous and non-proteinaceous amino acid formation in tea (Camellia sinensis) provides new insights into the safe and effective alteration of tea flavor and function

Abstract

Amino acids are the main contributors to tea (Camellia sinensis) flavor and function. Tea leaves contain not only proteinaceous amino acids but also specialized non-proteinaceous amino acids such as L-theanine and γ-aminobutyric acid (GABA). Here, we review different regulatory mechanisms of proteinaceous and non-proteinaceous amino acid formation in tea. The key findings were: (1) High accumulations of proteinaceous amino acids mainly result from protein degradation, which occurs in each tea stage, including preharvest, postharvest, manufacturing, and deep processing; (2) L-Theanine is the most represented non-proteinaceous amino acid that contributes to tea taste and function. Its accumulation is influenced more by the variety than by exogenous factors; and (3) GABA is the second most represented non-proteinaceous amino acid that contributes to tea function. Its formation, and resulting accumulation, are responses to stress. The combination of anoxic stress and mechanical damage are essential for a high GABA accumulation. An understanding of the biosynthesis, metabolism, and regulatory mechanisms of the proteinaceous and non-proteinaceous amino acids during the whole process from raw materials to tea products is necessary to safely and effectively alter tea flavor and function.