Cu-Fe Catalysts Modified by Rare Earths for Preparation of High Alcohols from Fatty Acid Esters Reduction

In order to increase activity of Cu Fe catalyst and use the mixture of nitrogen and hydrogen directly for preparation of high alcohols by reducing fatty acid esters, rare earths were used to modify the catalyst. Experiments show that yield of high alcohols increases by 3% as 1% Sm 2O 3 is added to the catalyst when the reduction is carried out under pure hydrogen. The yield greatly decreases when the reduction is carried out under the mixture of hydrogen and nitrogen. Catalysts activities modified by Y and Nd can be evidently improved and even enhanced. The yields increase by 33% and 29% when 1% Y 2O 3 and 1% Nd 2O 3 are added to the catalyst, respectively.

Prolonged high-fat-diet feeding promotes non-alcoholic fatty liver disease and alters gut microbiota in mice

BACKGROUND Non-alcoholic fatty liver disease (NAFLD) has become an epidemic largely due to the worldwide increase in obesity. While lifestyle modifications and pharmacotherapies have been used to alleviate NAFLD, successful treatment options are limited. One of the main barriers to finding safe and effective drugs for long-term use in NAFLD is the fast initiation and progression of disease in the available preclinical models. Therefore, we are in need of preclinical models that (1) mimic the human manifestation of NAFLD and (2) have a longer progression time to allow for the design of superior treatments. AIM To characterize a model of prolonged high-fat diet (HFD) feeding for investigation of the long-term progression of NAFLD. METHODS In this study, we utilized prolonged HFD feeding to examine NAFLD features in C57BL/6 male mice. We fed mice with a HFD (60% fat, 20% protein, and 20% carbohydrate) for 80 wk to promote obesity (Old-HFD group, n = 18). A low-fat diet (LFD)(14% fat, 32% protein, and 54% carbohydrate) was administered for the same duration to age-matched mice (Old-LFD group, n = 15). An additional group of mice was maintained on the LFD (Young-LFD, n = 20) for a shorter duration (6 wk) to distinguish between age-dependent and age-independent effects. Liver, colon, adipose tissue, and feces were collected for histological and molecular assessments.RESULTS Prolonged HFD feeding led to obesity and insulin resistance. Histological analysis in the liver of HFD mice demonstrated steatosis, cell injury, portal and lobular inflammation and fibrosis. In addition, molecular analysis for markers of endoplasmic reticulum stress established that the liver tissue of HFD mice have increased phosphorylated Jnk and CHOP. Lastly, we evaluated the gut microbial composition of Old-LFD and Old-HFD. We observed that prolonged HFD feeding in mice increased the relative abundance of the Firmicutes phylum. At the genus level, we observed a significant increase in the abundance of Adercreutzia, Coprococcus, Dorea, and Ruminococcus and decreased relative abundance of Turicibacter and Anaeroplasma in HFD mice. CONCLUSION Overall, these data suggest that chronic HFD consumption in mice can mimic pathophysiological and some microbial events observed in NAFLD patients.

Determinants of alcohol drinking and its association with sexual practices among high school students in Addis Ababa, Ethiopia: Cross sectional study

Introduction: Alcohol drinking and risky sexual practices have become serious public health problem among teenagers and young adults globally, including many developing countries. The available reports are sparse, especially there is a lack of recent and representative data for high school students in developing countries including Ethiopia. The aim of this study was to estimate the prevalence, identify determinants, and examine the association of alcohol drinking with sexual practices among high school students in Addis Ababa, capital city of Ethiopia. Methods: School based cross sectional study was conducted from November to December 2010. Multivariate logistic regression analysis was used to determine the association between students’ background characteristics and alcohol use, and alcohol use and sexual practices. Results: Among 2551 students surveyed, lifetime and current (past month) alcohol drinking was reported by 1166 (45.7%) and 676 (26.5%) students, respectively. Having sexual intercourse at least once in their lifetime was reported by 412 (16.2%) with151 (5.9%) of them being sexually active during a month prior to the survey. Having multiple sexual partners (52.5%), drinking alcohol before sexual intercourse (26.4%), and having sexual intercourse without the use of condom (47.3%) were also common among sexually active students. In adjusted logistic regression model, age (18 and 19 and older), living with 2 parents, getting pocket money, having alcohol drinking friends and attending general secondary school (grade 9-10) were positive predictors of current alcohol drinking. Nergative predictors of current alcohol drinking were being Protestant Christian and living with relatives or siblings. Conclusion: Alcohol drinking before sexual intercourse was a major problem among high school students in Addis Ababa, Ethiopia. Male gender, older age and higher school grade, friends influence, religious affiliation, living with parents and getting pocket money were significant predictors of current alcohol drinking. Educating about substance use and risky sexual behaviors, engaging students in extracurricular activities and restrict access to alcohol to high school students may help in solution of these problems on a local scale.

Mitochondrial metabolomic profiling for elucidating the alleviating potential of Polygonatum kingianum against high-fat diet-induced nonalcoholic fatty liver disease

BACKGROUND Developing mitochondrial regulators/nutrients from natural products to remedy mitochondrial dysfunction represent attractive strategies for therapy of nonalcoholic fatty liver disease(NAFLD).Polygonatum kingianum(PK)has been traditionally used in China as a medicinal and nutritional ingredient for centuries and can alleviate high-fat diet(HFD)-induced NAFLD by promoting mitochondrial functions.To date,the underlying molecular mechanism of PK for treating mitochondrial dysfunctions and thus alleviating NAFLD remains unclear.AIM To identify the molecular mechanism behind the mitochondrial regulatory action of PK against HFD-induced NAFLD in rats.METHODS NAFLD model was induced in rats with HFD.The rats were intragastrically administered PK(4 g/kg per day)for 14 wk.Metabolites in hepatic mitochondrial samples were profiled through ultra-high performance liquid chromatography/mass spectrometry followed by multivariate statistical analysis to find the potential biomarkers and metabolic pathways.RESULTS PK significantly restored the metabolites’levels in the mitochondrial samples.Ten potential biomarkers were identified in the analyzed samples.These biomarkers are involved in riboflavin metabolism.CONCLUSION PK can alleviate HFD-induced NAFLD by regulating the riboflavin metabolism and further improving the mitochondrial functions.Thus,PK is a promising mitochondrial regulator/nutrient for alleviating NAFLD-associated diseases.

Comparison of the Contributions of Tetrahydrofurfuryl Alcohol and PEG to a-Chymotrypsin Renaturation with High Performance Hydrophobic Interaction Chromatography

The contributions of tetrahydrofurfuryl alcohol (THFA) and polyethylene glycol (PEG) to the renatured efficiency of a-chymotrypsin were investigated and compared with each other. The maximum increments of bioactivity recovery of a-Chy were found to be 25.1% for THFA, 10.4% for PEG, respectively. The experimental results indicated that the denaturant solution containing THFA contributed more to the renaturation of a-Chy in high performance hydrophobic interaction chromatography (HPHIC) than that containing PEG, when the concentration of THFA was 3.2%, the bioactivity recovery of a-Chy is the highest.

婴儿肠道源长双歧杆菌B2-01的益生特性及其高密度培养

以广州市3月龄健康婴儿粪便中分离出的乳酸杆菌为研究对象,经分子生物学鉴定确认为长双歧杆菌(Bifidobacterium longum),命名为B2-01。对B2-01进行包括体外抗氧化活性和肝损伤保护活性在内的益生特性和高密度培养研究,结果表明:B2-01具有较强的1,1-二苯基-2-三硝基苯肼自由基、羟自由基、超氧阴离子自由基、2,2′-联氮-双-(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基清除能力和抗脂质过氧化能力;在最高作用水平(DMEM完全培养基中发酵上清液体积分数10%)下,过氧化氢损伤和乙醇损伤L02细胞存活率可分别提高至89.10%和91.38%,同时能显著降低肝细胞中转氨酶的活力;高密度培养研究优化后的最佳培养条件确定为酵母浸提粉添加量3.45%、葡萄糖2.48%、乳糖2.79%、细菌学蛋白胨3.00%、低聚半乳糖2.50%。在此优化条件下,发酵液的活菌数最高可达4.20×10^(9) CFU/m L,比优化前(7.71×10^(8) CFU/mL)提高5.45倍。

Towards a standard diet-induced and biopsy-confirmed mouse model of non-alcoholic steatohepatitis: Impact of dietary fat source

BACKGROUND The trans-fat containing AMLN(amylin liver non-alcoholic steatohepatitis,NASH)diet has been extensively validated in C57BL/6J mice with or without the Lep^ob/Lep^ob(ob/ob)mutation in the leptin gene for reliably inducing metabolic and liver histopathological changes recapitulating hallmarks of NASH.Due to a recent ban on trans-fats as food additive,there is a marked need for developing a new diet capable of promoting a compatible level of disease in ob/ob and C57BL/6J mice.AIM To develop a biopsy-confirmed mouse model of NASH based on an obesogenic diet with trans-fat substituted by saturated fat.METHODS Male ob/ob mice were fed AMLN diet or a modified AMLN diet with trans-fat(Primex shortening)substituted by equivalent amounts of palm oil[Gubra amylin NASH,(GAN)diet]for 8,12 and 16 wk.C57BL/6J mice were fed the same diets for 28 wk.AMLN and GAN diets had similar caloric content(40%fat kcal),fructose(22%)and cholesterol(2%)level.RESULTS The GAN diet was more obesogenic compared to the AMLN diet and impaired glucose tolerance.Biopsy-confirmed steatosis,lobular inflammation,hepatocyte ballooning,fibrotic liver lesions and hepatic transcriptome changes were similar in ob/ob mice fed the GAN or AMLN diet.C57BL/6J mice developed a mild to moderate fibrotic NASH phenotype when fed the same diets.CONCLUSION Substitution of Primex with palm oil promotes a similar phenotype of biopsyconfirmed NASH in ob/ob and C57BL/6J mice,making GAN diet-induced obese mouse models suitable for characterizing novel NASH treatments.

mi R-192-5p regulates lipid synthesis in non-alcoholic fatty liver disease through SCD-1

AIM To evaluate the levels of mi R-192-5 p in non-alcoholic fatty liver disease(NAFLD) models and demonstrate the role of mi R-192-5 p in lipid accumulation. METHODS Thirty Sprague Dawley rats were randomly divided into three groups, which were given a standard diet, a high-fat diet(HFD), and an HFD with injection of liraglutide. At the end of 16 weeks, hepatic mi R-192-5 p and stearoyl-Co A desaturase 1(SCD-1) levels were measured. Mi R-192-5 p mimic and inhibitor and SCD-1 si RNA were transfected into Huh7 cells exposed to palmitic acid(PA). Lipid accumulation was evaluated by oil red O staining and triglyceride assays. Direct interaction was validated by dual-luciferase reporter gene assays.RESULTS The HFD rats showed a 0.46-fold decrease and a 3.5-fold increase in hepatic mi R-192-5 p and SCD-1 protein levels compared with controls, respectively, which could be reversed after disease remission by liraglutide injection(P < 0.01). The Huh7 cells exposed to PA also showed down-regulation and up-regulation of mi R-192-5 p and SCD-1 protein levels, respectively(P < 0.01). Transfection with mi R-192-5 p mimic and inhibitor in Huh7 cells induced dramatic repression and promotion of SCD-1 protein levels, respectively(P < 0.01). Luciferase activity was suppressed and enhanced by mi R-192-5 p mimic and inhibitor, respectively, in wild-type SCD-1(P < 0.01) but not in mutant SCD-1. Mi R-192-5 p overexpression reduced lipid accumulation significantly in PA-treated Huh7 cells, and SCD-1 si RNA transfection abrogated the lipid deposition aggravated by mi R-192-5 p inhibitor(P < 0.01).CONCLUSION This study demonstrates that mi R-192-5 p has a negative regulatory role in lipid synthesis, which is mediated through its direct regulation of SCD-1.

鸡血藤纤维样物质药用价值的研究与评价

目的分析鸡血藤饮片粉碎后未过筛网的纤维样物质是否具有回收利用价值。方法鸡血藤样品粉碎过筛分为细粉与纤维样物质,分别经过不同的药典筛得不同孔径的细粉与纤维样物质,编号后依次经50%甲醇超声提取得提取液,采用高效液相色谱(HPLC)法测定所得样品中儿茶素的含量,以确定鸡血藤中纤维样物质的回收利用价值。色谱条件为Agilent C18色谱柱(4.6 mm×100 mm,2.6μm),流动相为乙腈(A)-0.2%磷酸水溶液,等度洗脱,体积比为10∶90,流速1.3 mL·min^(-1),检测波长278 nm。结果鸡血藤中含有较多的纤维样物质,约占药材总重的15%。纤维样物质浸出物含量均>8%,但与过6号筛的粉末比较,含量较低。纤维样物质中儿茶素含量较少,约为粉末中含量的50%。结论鸡血藤中纤维样物质的粉碎过筛过程较为繁琐,在制剂过程中影响剂型外观和患者口服感受,在临床使用中可直接抛弃,节约时间与制作成本。

三酰甘油与高密度脂蛋白胆固醇比值对非酒精性脂肪性肝病严重程度的预测价值

目的探讨三酰甘油(TG)与高密度脂蛋白胆固醇(HDL-C)的比值(TG/HDL-C)对非酒精性脂肪性肝病(NAFLD)严重程度的预测价值。方法选取2021年6月至2022年12月在武汉科技大学附属孝感医院健康管理部进行健康体检且诊断为NAFLD患者526例,根据腹部超声检查结果,分为轻度366例、中度129例、重度31例,比较3组间一般资料、生化指标、TG/HDL-C的差异及其相关性,绘制受试者工作特征(ROC)曲线,评价TG/HDL-C对NAFLD严重程度的预测价值。结果(1)3组间体重、体重指数(BMI)、腰围、腰臀比、收缩压、舒张压、TG、HDL-C、TG/HDL-C、天门冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)、空腹血糖(FPG)、尿酸(UA)、脂肪百分比、内脏脂肪面积比较,差异均有统计学意义(P<0.05)。其中,与轻度NAFLD组比较,中度与重度NAFLD组体重、BMI、腰围、腰臀比、TG、TG/HDL-C、ALT、AST、脂肪百分比、内脏脂肪面积均升高,差异均有统计学意义(P<0.05);与中度NAFLD组比较,重度NAFLD组BMI、TG、TG/HDL-C、ALT、AST、UA升高,HDL-C降低,差异均有统计学意义(P<0.05)。(2)TG/HDL-C与腰围、臀围、腰臀比、BMI、舒张压、TC、FPG、UA、ALT、AST、内脏脂肪面积、TG呈正相关;与HDL-C呈负相关。(3)ROC曲线显示,TG/HDL-C诊断中重度NAFLD的截点值为1.76,灵敏度和特异度分别为0.494、0.787。结论TG/HDL-C与NAFLD严重程度密切相关,TG/HDL-C可用于临床上NAFLD的严重程度的预测。

三次采油用月桂醇聚氧乙烯醚非离子表面活性剂的高效液相色谱分析检测方法

为了建立三次采油用月桂醇聚氧乙烯醚非离子表面活性剂的液相色谱分析检测方法,通过对色谱要素的优化实验,确立了最佳色谱条件,并进行了方法学评价。实验确定色谱柱为羟基柱,规格为150 mm×4.6 mm;流动相为乙腈与水;梯度洗脱(0~3 min:25%乙腈/75%水;3~8 min:90%乙腈/10%水;8.01 min:25%乙腈/75%水);流速为1.0 mL/min;质谱检测器正模式检测;进样量为2μL。该方法在20~200 mg/L浓度范围内线性相关系数R=0.99998,检出限低至5 mg/L,加标回收率在88.10%~97.14%之间,10 min完成一次分析,展现了检测结果准确、检测方法灵敏、快速的色谱学优点,能够满足复杂采出液中月桂醇聚氧乙烯醚非离子表面活性剂的定量检测。因采用质谱检测器,可同时开展油井采出液中月桂醇聚氧乙烯醚非离子表面活性剂的结构鉴定。

草菇子实体多肽对小鼠急性酒精肝的预防作用及肠道菌群的影响

为了探究草菇子实体多肽(Volvariella volvacea fruit body polypeptides,VVFP)对模型小鼠急性酒精肝预防作用及肠道菌群的影响,以先前获得的VVFP(分子质量1~3 kDa)为材料灌胃小鼠,将小鼠随机分为空白组、模型组、阳性对照组、多肽低剂量组、多肽中剂量组、多肽高剂量组,比较各组小鼠的血清和肝脏指标以及组织病理切片,利用16S rDNA基因高通量测序分析各样品中微生物菌群的生物多样性以及在门和属水平上的相对丰度。结果表明,与模型组相比,VVFP能够极显著降低血清中甘油三酯、总胆固醇、谷丙转氨酶、谷草转氨酶水平和肝脏中丙二醛的含量,并且降低肿瘤坏死因子-α、白细胞介素-6炎症因子水平,同时明显提高肝脏中乙醇脱氢酶、总超氧化物歧化酶和谷胱甘肽过氧化物酶的活性。16S rDNA基因高通量测序结果表明,VVFP可以使小鼠肠道菌群中α多样性的Chao1指数和Observed_species指数明显降低,Shannon指数升高,并可通过调节拟杆菌门、厚壁菌门、链霉菌属、乳酸杆菌属和弧菌属的丰度从而减轻小鼠肝脏的损伤程度。综上,VVFP可以减轻酒精引起的肝损伤,本研究可为多肽在功能食品领域的应用提供理论参考。

高温后钢-PVA混杂纤维高性能混凝土与变形钢筋黏结性能试验

为研究高温后钢-聚乙烯醇(polyvinyl alcohols,PVA)混杂纤维高性能混凝土(hybrid fiber high performance concrete,HFHPC)与变形钢筋的黏结性能退化规律,以200、400、600、800℃为目标温度,选取钢纤维体积率、PVA纤维体积率、矿粉掺量为正交试验因素设计并制作25组HFHPC试件,完成了单调荷载下的中心拉拔试验。结果表明:高温后各组HFHPC试件黏结破坏形态均表现为钢筋拔出破坏;试验温度范围内,对HFHPC试件黏结强度的影响程度均为:钢纤维体积率最大、矿粉掺量次之、PVA纤维体积率最小;随着温度的升高,HFHPC试件黏结强度逐渐下降,且在相同温度条件下,HFHPC试件黏结强度和峰值滑移相比于未掺纤维的混凝土试件均有所提升,其中,200℃时HFHPC试件的黏结强度提升最为显著,分别提升了33.69%、35.76%、37.54%和46.03%;混杂纤维能显著提高高温后高性能混凝土与钢筋的峰值界面能,明显改善黏结延性和耗能能力;提出的考虑温度作用后的混杂纤维混凝土与钢筋黏结-滑移模型与试验实测结果吻合较好,可为火灾后混杂纤维高性能混凝土结构损伤评估及加固方案提供参考。

铁过载对不同类型高脂膳食所致肝损伤的影响

目的:探究铁过载联合不同类型高脂膳食对小鼠肝损伤的影响。方法:将48只SPF级雄性C57BL/6J小鼠按体重随机分为6组,每组8只,普通对照组(ND)、高铁对照组(NDFe)给予基础饲料,棕榈油高脂组(PHFD)、棕榈油高脂高铁组(PHFDFe)、大豆油高脂组(SHFD)和大豆油高脂高铁组(SHFDFe)分别给予对应高脂饲料。从第10周开始,NDFe、PHFDFe和SHFDFe组连续8周每周两次肌肉注射右旋糖酐铁100 mg/kg·bw,其余组注射等剂量生理盐水至第17周。麻醉后取血和肝脏,测定小鼠血清和肝脏生化指标、肝脏病理改变及铁代谢和脂代谢相关基因表达。结果:与对应高脂组相比,铁过载联合高脂膳食可使血清总胆固醇(Total cholesterol,TC)、肝脏甘油三酯(Triglyceride,TG)和谷胱甘肽过氧化物酶(Glutathione peroxidase,GSH-Px)水平显著下降(P<0.05),血清TG和谷丙转氨酶(Alanine aminotransferase,ALT)水平、肝脏系数、肝脏铁含量和丙二醛(Malondialdehyde,MDA)水平显著升高(P<0.05),SHFDFe组肝脏MDA水平显著高于PHFDFe组(P<0.05)。PHFDFe组二价金属转运蛋白1(Divalentmetal-iontransporter-1,DMT-1)和膜铁转运蛋白(Ferroportin,FPN)mRNA表达量显著高于PHFD组(P<0.05);SHFDFe组FPN mRNA表达量显著高于与NDFe、PHFDFe和SHFD组(P<0.05),乙酰CoA羧化酶1(acetyl-Coenzyme A carboxylase alpha 1,ACC1)和脂肪酸合酶(Fatty Acid Synthase,FASN)mRNA表达量显著低于SHFD组(P<0.05)。结论:铁过载联合高脂膳食会加重脂质代谢紊乱和氧化应激,铁过载联合大豆油高脂饲料喂养导致的肝损伤高于联合棕榈油高脂饲料喂养。

气田注醇用柔性复合管服役性能

采用涤纶纤维增强尼龙内衬的柔性复合管在气田高压注醇环境中得到大量应用,随着服役时间的增加,管线本体老化和接头失效频发。为明确该类柔性复合管在气田注醇环境应用后性能变化及其工况适应性,针对服役前后柔性复合管各功能层,开展了形貌分析、理化性能分析及承压性能测试。结果表明,在高压注醇环境服役后复合管尼龙内衬层材料和涤纶纤维增强层材料外观发生了一定变化,外保护层龟裂。在甲醇介质作用下服役后的复合管尼龙内衬层材料初始热分解温度和熔融焓降低。甲醇介质经内衬层渗透进入柔性复合管夹层,聚酯纤维与醇类基团发生解聚反应,致使复合管服役后的纤维拉伸性能及在役管线爆破强度显著降低。管体爆破强度降低情况与纤维拉伸性能具有较好的一致性,且接头为薄弱部位。原有PA1212和PA66内衬材料不能长期适用于现场高压注醇工况环境,后期建议使用前针对内衬材料开展耐甲醇介质溶胀及渗透性能选材评价。

BP神经网络算法结合超高效液相色谱-质谱联用技术研究红花治疗慢性酒精性肝损伤的作用机制

临床上,红花对慢性酒精性肝损伤(chronic alcoholic liver injury,CALI)有很好的疗效,但治疗机制不甚明确。因此,阐明红花治疗CALI的分子作用机制对药物的进一步开发及应用具有重要意义。以雄性Wistar大鼠为研究对象,模型组大鼠以8 mL/kg酒精连续灌胃28天,建立CALI模型;给药组大鼠分别以高(4.290 3 g/kg)、中(1.430 1 g/kg)、低(0.476 7 g/kg)剂量灌胃红花提取物。采用大鼠血清代谢组学分析方法结合超高效液相色谱-质谱技术鉴定与CALI相关的潜在生物标志物,并研究红花对这些生物标志物的调控机制。利用MATLAB软件建立BP神经网络模型处理组学数据的分类问题。从苏木精和伊红(H&E)染色实验发现,高剂量红花提取物减轻了肝细胞的损伤程度;与模型组相比,高剂量红花组中的丙氨酸氨基转移酶(ALT)和天冬氨酸氨基转移酶(AST)的表达水平降低,表明高剂量红花提取物具有肝保护作用。BP神经网络模型的分类准确率为95.8%,分类效果良好。通过火山图分析共鉴定出20种与CALI相关的生物标志物,红花可以对这些生物标志物产生回调效果。研究表明,红花可能通过对甘油三酯、脂肪酸、磷脂、胆汁酸、氨基酸、维生素E代谢的调控作用而对CALI产生治疗效果。本研究可为红花的推广和临床应用提供了理论基础。

酒精及高脂饮食双重诱导下脂肪肝的转录组学变化分析

目的通过酒精灌胃和高脂饮食诱导脂肪肝小鼠模型,观察小鼠肝脏表型和转录组学的改变,分析酒精、高脂饮食和联合饮食对肝脏的危害性。方法实验小鼠分为对照组(PBS)、高脂饲喂组(高脂饲料)、酒精灌胃组(40%酒精)、联合饲喂组(酒精+高脂饲料)。HE染色观察各组小鼠肝脏组织病理形态。提取肝脏RNA进行转录组测序,并针对各组转录组学的变化进行分析,观察在单一风险因素作用下和双重风险因素作用下对肝脏的影响。构建基因表达调控网络锁定网络核心基因,并对其进行验证。结果在病理层面,联合饲喂组肝脏相较于单一风险因素各组表现出更为严重的脂质累积和炎症。转录组学分析结果显示,联合饲喂组的基因表达相较于单纯的高脂饲喂组和酒精灌胃组表现出了更为明显的脂质累积通路的活跃和恶化倾向。对单风险因素和双重风险因素的差异表达基因取交集,筛选出了导致脂肪肝肝损伤的主要风险基因。功能分析结果显示高脂饮酒小鼠肝脏的基因表达变化不仅包括脂肪代谢异常,同时也和药物的不良代谢有关,最终导致肝脏炎症增加。通过网络分析可以确定Acacb,Cyp2b10和Cd36可能是高脂饮群体肝脏基因表达变化的主要靶点。结论饮酒和高脂饮食对肝脏的影响虽然都和脂肪累积引起脂肪肝相关,但并不完全一样,高脂饮食人群饮酒会对肝脏产生更严重的影响。然而关于高脂饮食和饮酒对肝脏的具体作用机制有待于进一步深入探索。

低产杂醇高产酯酵母菌株的选育和共酵对黄酒品质的影响及机制分析

杂醇和酯是影响黄酒品质的关键化合物,寻找发酵性能优良的酵母菌株,开发低产杂醇高产酯的发酵工艺具有重要的理论价值和应用前景。以酿酒酵母jiangnan1#作为出发菌株,通过紫外诱变、常压室温等离子体诱变技术,以实验室模拟发酵制得的黄酒中杂醇、酯类化合物质量浓度为评价指标,筛选出1株优良的突变菌株,命名为YAR28。对YAR28进行了生孢纯化筛选,获得1株产醇酯较佳的酿酒酵母,命名为酿酒酵母Y28-23。将酿酒酵母Y28-23连续5次传代培养,进行稳定性验证,结果显示,该酿酒酵母的酒精产量没有显著性差异(P>0.05),但产杂醇的质量浓度[(378.16±28.76)mg/L]比出发菌株降低了21.41%,且产酯的质量浓度[(152.86±19.73)mg/L]增加了35.57%。将酿酒酵母Y28-23与52株具备潜在产酯性能的非酿酒酵母共酵,以低产杂醇高产酯为评价指标,最终确定了异常威克汉姆酵母Y34为较佳的非酿酒酵母。进一步优化酿酒酵母Y28-23与异常威克汉姆酵母Y34的共酵条件,发现在主发酵阶段的温度为20℃的条件下以1∶10的添加比例共酵黄酒,对于黄酒醇酯比的优化效果较佳,杂醇的质量浓度为(281.20±5.73)mg/L,酯类的质量浓度为(240.02±2.47)mg/L。相比于单菌发酵,黄酒中杂醇的质量浓度降低了25.63%,而酯类的质量浓度增加了57.13%。基于代谢组学分析,获得多条与黄酒发酵过程中底物利用及风味形成密切相关的差异代谢物和代谢通路,阐明了黄酒共酵过程中异常威克汉姆酵母Y34对酿酒酵母Y28-23的代谢调节作用。研究可为利用发酵菌株控制黄酒酿造过程中的醇酯含量提供技术支持,对黄酒发酵菌种资源的开发利用以及黄酒品质的提升具有参考价值。

ARTP诱变筛选增香、高产酒精的富硒酵母菌

为了得到产酒精和产香能力较强的枸杞内生富硒酵母菌,进而促进富硒发酵产品的开发和风味的提升,本研究以实验室保藏的枸杞内生酵母菌为实验材料,通过耐硒法和红硒法初筛得到富硒能力较强的酵母菌,采用常压室温等离子体(Atmospheric room temperature plasma,ARTP)诱变技术,经TTC培养基、杜氏小管发酵法、产酒精、产酯产酸、耐受性等实验筛选出增香和高产酒精的目标菌株,并用氢化物发生原子荧光光谱法测定酵母胞内和发酵液中硒含量。结果表明,富硒初筛得到了M1酿酒酵母(Saccharomyces cerevisiae)和M16葡萄牙棒孢酵母(Clavispora lusitaniae),经ARTP诱变分别筛选出产酒精能力较高的S.cerevisiae诱变菌株M1-5和产香能力较高的C.lusitaniae诱变菌株M16-28,M1-5的产酒精能力比M1提高了38.07%,M16-28的产酯能力比M16提升了107.62%,遗传稳定性均良好。经测定M1-5菌株胞内和发酵液中的硒含量分别为204.8和1158μg/L,M16-28胞内和发酵液中的硒含量分别为666.45和1830μg/L,因此,菌株M16-28比M1-5的富硒能力强,且发酵液硒含量极显著高于酵母细胞硒含量(P<0.001)。本研究筛选出诱变菌株M1-5产酒精和M16-28产香能力强的富硒酵母具有优良的发酵特性,在发酵食品和富硒功能性产品的挖掘和开发方面具有潜在的应用前景。

不同高脂饲料配方对建立非酒精性脂肪肝大鼠模型的影响

目的:比较3种不同配方高脂饲料构建非酒精性脂肪肝大鼠模型的差异,提高高脂饲料建立非酒精性脂肪肝大鼠模型的成功率,为非酒精性脂肪肝病的研究提供稳定可靠的动物模型。方法:将SPF级雄性SD大鼠随机分为普通饲料对照组、高脂饲料1组(HFD1组)、高脂饲料2组(HFD2组)、高脂饲料3组(HFD3组)。各组大鼠分别给予相应饲料8周。造模期间记录大鼠一般情况、体质量和摄食量。喂养8周后,采用腹部超声、计算机断层扫描(CT)、核磁共振成像(MRI)对大鼠肝脏进行检查。取血和肝脏,检测肝功能指标(丙氨酸氨基转移酶、天门冬氨酸氨基转移酶)、血脂指标(甘油三酯、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇)和炎症指标(IL-1β、IL-6、TNF-α)的变化。肉眼观察肝脏大体形态,计算其肝指数和Lee’s指数。比较上述指标在各组间的差异,综合评估不同配方高脂饲料对非酒精性脂肪肝大鼠模型的影响。结果:与对照组大鼠相比,HFD1组、HFD2组、HFD3组大鼠精神变差、活动减少、脱毛现象加重、摄食量减少、体质量明显升高,肝指数、Lee’s指数显著提高,肝脏体积增大,边缘较钝,可见脂肪变性和沉积,且以HFD3组大鼠变化最为明显;HFD1组、HFD2组、HFD3组大鼠血清谷丙转氨酶、天门冬氨酸氨基转移酶、甘油三酯、总胆固醇、低密度脂蛋白胆固醇和IL-1β、IL-6、TNF-α水平均显著升高,高密度脂蛋白胆固醇显著降低,且HFD3组更为明显;HFD1组、HFD2组、HFD3组大鼠肝脏肿大,实质回声增强,肝内管状结构显示欠清,肝和脾的CT值比值明显降低,同/反相位图上肝脏实质信号差别明显,且HFD3组对于大鼠影像学变化影响更大。结论:三种高脂饲料喂养SD大鼠8周后,均可建立非酒精性脂肪肝大鼠模型,但HFD3组诱导非酒精性脂肪肝大鼠模型优于其他两组,病变相对严重,预计维持时间也更长,更适于非酒精性脂肪肝病的机制研究和降脂药物的筛选。