Effects of choline chloride on the ruminal microbiome at 2 dietary neutral detergent fiber concentrations in continuous culture

Our objective was to evaluate the effects of unprotected choline chloride (Cho) on the ruminal microbiome at 2 dietary neutral detergent fiber (NDF) concentrations. We hypothesized that the effects of Cho on ruminal bacterial populations would depend on NDF. Eight dual-flow continuous-culture fermentors were arranged in a duplicated 4 × 4 Latin square as a 2 × 2 factorial with the following treatments: (1) 30% NDF-control (30% NDF diet, no supplemental choline); (2) 30% NDF-Cho (30% NDF diet plus 1.9 g of choline ion per kg of dry matter); (3) 40% NDF-control (40% NDF diet, no supplemental choline); and (4) 40% NDF-Cho (40% NDF diet plus 1.9 g of choline ion per kg of dry matter). We did 4 fermentation periods of 10 d each and used the last 3 d for collection of samples of solid and liquid digesta effluents for DNA extraction. Overall, 32 solid and 32 liquid samples were analyzed by amplification of the V4 variable region of bacterial 16S rRNA. Data were analyzed with R (R Project for Statistical Computing) and SAS (SAS Institute Inc.) to determine effects of Cho, NDF, and NDF × Cho on taxa relative abundance. The correlation of propionate molar proportion with taxa relative abundance was also analyzed. At the phylum level, relative abundance of Firmicutes in the liquid fraction tended to be greater when Cho was supplemented with a 30% NDF diet. At the order level, Cho increased Coriobacteriales in solid fraction and decreased Fibrobacterales in liquid fraction. Moreover, Cho decreased abundance of Clostridiales and increased Selenomonadales in the solid fraction, only with the 30% NDF diet. For genera, lower abundance of Pseudobutyrivibrio resulted from Cho in solid and liquid fractions. Greater abundance of Succinivibrio in solid and Selenomonas and Selenomonas 1 in liquid resulted from Cho with the 30% NDF diet. Propionate molar proportion was positively correlated with relative abundance of order Selenomonadales in solid and liquid fractions, and with genus Succinivibrio in solid and genera Selenomonas and Selenomonas 1 in liquid. Our results indicate that Cho primarily decreases abundance of bacteria involved in fiber degradation and increases abundance of bacteria mainly involved in nonstructural carbohydrate degradation and synthesis of propionate, particularly when a diet with 30% NDF is provided.     

Carbon nanotube–polyaniline composites

The last decade has seen a growing interest in hybrid electrically conducting nanocomposites. This article aims to provide a detailed overview of the present status of research in carbon nanotube–polyaniline (CNT/PANI) composites, from processing to structural and property evaluations. CNT/PANI are synthesized by electrochemical and chemical processing. When chemical methods are used, the main challenge is to obtain processable CNT/PANI in the emeraldine salt (ES) form composites. Stable dispersions of ES–CNT in organic media are prepared using the post doping method, inverse emulsion polymerization, or ex situ polymerizations. On the contrary, stable water dispersions of CNT/ES are prepared using hydrophilization of a preformed CNT/ES composite, direct synthesis of micelle–CNT hybrid templates, interfacial polymerization, covalent functionalization of CNT with a water soluble polymer, or using electrostatic interactions between two oppositely charged ES and CNT aqueous colloids. Moreover, the strategies for the synthesis of ternary CNT/PANI composites incorporating noble metal nanoparticles, metal oxide, or graphene sheets are also presented and analyzed in depth. Finally, we give a review of potential applications, including chemical sensors, capacitors, fuel cells and electronic devices.     

胆碱模块自动化合成11C-carfentanil及Micro PET显像

为快速、高效合成中枢神经阿片受体显像剂¹¹C-carfentanil(¹¹C-CFN),对国产商业化¹¹C-胆碱合成模块略做改动,并优化了合成条件。结果表明,采用4-哌啶乙酸钠,4-[(1-丙羰基)苯胺]-1-(2-苯乙基)[钠盐]作前体,DMSO作溶剂,¹¹CH_3-triflate作甲基化试剂,在胆碱模块上采用反应瓶法,可自动化合成¹¹C-CFN。合成的¹¹C-CFN活度＞14.8 GBq、比活度＞1.4×10¹⁴Bq/g、放化纯度＞99%,校正合成效率＞80%（n=55,以¹¹CH₃-triflate计算）,全部合成时间为18 min。经Micro PET/CT证实,¹¹C-CFN可用于μ阿片受体的PET显像研究。     

Cleavable surfactants

Cleavable surfactants are of interest for several reasons. Above all, the development of surfactants with weak bonds deliberately built into the structure is driven by the need for improved biodegradability of amphiphiles. The breakdown may be catalyzed by enzymes, and biodegradation would be the normal mechanism in sewage plants. Alternatively, the surfactant may degrade by chemical means, e.g., induced by acid, alkali, ultraviolet (UV) light, heat, or ozone. Acid- and alkali-labile surfactants have attracted particular attention, and there is often a compromise between required stability at one stage and ease of breakdown at a subsequent stage. The paper reviews the main routes used to prepare cleavable surfactants and points out advantages and disadvantages of the different approaches. Emphasis is placed on the development during recent years. Cyclic and acyclic acetals, ketals, and ortho esters are the most important types of bonds for the preparation of acid-labile surfactants, whereas alkali-labile amphiphiles usually are based on ester bonds. The ester bond approach has been particularly important for cationic surfactants, and so-called ester quats have rapidly taken a large share of the traditional market for quats. Betaine esters constitute a special class of ester with very pronounced pH dependence. UV-labile surfactants based, for instance, on an azo bond, offer promise for the future.     

氯化胆碱合成工艺的研究

在氯化胆碱的作用下,三甲胺与氯乙醇反应合成氯化胆碱。讨论了影响产品收率及纯度的主要因素。实验发现氯化胆碱有自催化作用,在优化工艺条件下,氯化胆碱的收率达到95.8%,纯度达到98.0%。该工艺具有操作简单、易分离、易干燥、收率高、纯度高、成本低、易推广等优点。     

氧化铝柱层析分离纯化磷脂的工艺过程

研究了氧化铝柱层析同时分离纯化卵磷脂和脑磷脂的工艺过程,包括上样、洗脱工艺条件优化以及氧化铝再生等.结果表明较佳上样条件为：上样质量浓度为100 g/L,流动相为纯甲醇,流速为1.0~2.5 BV/h;较佳洗脱条件为：甲醇 氯仿溶液中氯仿的体积分数为80%;较佳再生条件为：用5个床层体积的甲醇冲洗层析柱.通过连续上样实验,验证了该工艺过程的可行性,可以同时得到质量分数大于95%的卵磷脂产品和质量分数大于80%的脑磷脂产品.氧化铝柱层析可以用于同时分离纯化卵磷脂和脑磷脂,具有粗磷脂处理量大以及产率和纯度高等优点     

可裂解的表面活性剂(英)(待续)

可裂解的表面活性剂值得关注有几方面的原因。首先,弱键联接的表面活性剂分子结构迎合了改善两亲性物质生物降解能力的发展趋势。裂解可以被酶催化,其生物降解作用可能与污水处理的一般发机理相符合。另外,这些表面活性剂也可以妥,例如,用酸、碱、此一（ＵＶ）、热或臭氧诱发降解反应,对酸、碱不稳定的表面活性剂已引起特别关注,因为在初始步骤所需的稳定性与其在后续步骤中应易裂解并不冲突。综述了制可裂解性表面活性剂的主     

Supplemental choline for prevention and alleviation of fatty liver in dairy cattle

Two experiments were conducted to evaluate if supplementing rumen-protected choline (RPC; Reashure, Balchem Encapsulates, Slate Hill, NY) could prevent or alleviate fatty liver in dairy cattle. The first experiment evaluated the effect of supplementing RPC on hepatic triacylglycerol (TAG) accumulation during fatty liver induction. Twenty-four dry cows between 45 to 60 d prepartum were paired by body weight (BW) and body condition score (BCS) and randomly assigned to control or supplementation with 15 g of choline as RPC/d. From d 0 to 6, before treatment application, all cows were fed 1.4 kg/d of concentrate and forage ad libitum. Samples of blood and liver, obtained during the pretreatment period, were used for covariate adjustment of blood metabolites and liver composition data. During fatty liver induction (d 7 to 17), cows were fed 1.4 kg/d of concentrate with or without supplementation with RPC, and forage intake was restricted, so cows consumed 30% of the total energy requirements for pregnancy and maintenance. Supplementation with RPC during fatty liver induction did not affect plasma glucose and plasma β-hydroxybutyrate (BHBA) concentration but did decrease plasma nonesterified fatty acid (NEFA; 703 vs. 562 μEq/L, SE = 40) and liver TAG accumulation (16.7 vs. 9.3 μg/μg of DNA, SE = 2.0). In the second experiment, we evaluated the effect of supplementing RPC on the clearance of liver TAG when cows were fed ad libitum after the induction of fatty liver by feed restriction. Twenty-eight cows between 45 and 60 d prepartum were paired according to BCS and BW and assigned to treatments. Fatty liver was induced by feeding 1.4 kg/ d of concentrate (without RPC) and restricting forage intake, so cows consumed 30% of maintenance and pregnancy energy requirements for 10 d. From d 11 to 16, after feed restriction, cows were fed forage ad libitum and 1.4 kg/d of concentrate with or without RPC. Treatments were not applied during fatty liver induction; however, following feed restriction, liver for cows assigned to control and RPC treatments contained 6.8 and 12.7 μg of TAG/μg of DNA, respectively. Measurements obtained before treatment served as covariates for statistical analysis. During the depletion phase, plasma glucose, BHBA, and NEFA were not affected by treatment. Liver TAG, expressed as covariate adjusted means, was 6.0 and 4.9 μg/μg of DNA (SE = 0.4) on d 13, and 5.0 and 1.5 μg/μg of DNA (SE = 0.9) on d 16 for control and RPC, respectively. Rumen-protected choline can prevent and possibly alleviate fatty liver induced by feed restriction.     

Lipid metabolite profiles and milk production for Holstein and Jersey cows fed rumen-protected choline during the periparturient period

Choline is important for assembly of very low density lipoproteins to export triglyceride from liver; however, studies to assess the effect of rumen-protected choline (RPC) supplementation on blood lipid metabolites in periparturient dairy cows have not been conducted. Thirty-two multiparous Holstein and 10 multiparous Jersey cows were randomly assigned to control or RPC treatments. A close-up diet was fed from approximately 3 wk before parturition through parturition, followed by a lactation diet from parturition through 49 d postpartum. For RPC, diets were top-dressed once daily with 60 g of a RPC product (25% choline as choline chloride) from 21 d before expected parturition through 21 d postpartum. Treatment did not affect dry matter intake either prepartum (12.0 vs. 12.1 kg/d for RPC and control, respectively) or during the first 3 wk postpartum (14.8 vs. 15.7 kg/d, respectively). Daily yields of 3.5% fat-corrected milk (39.4 vs. 37.4 kg/d), fat (1.46 vs. 1.38 kg/d), and protein (1.09 vs. 1.05 kg/d) did not differ statistically by treatment (RPC vs. control, respectively). Jersey cows in the control group had lower concentrations of nonesterified fatty acids and β-hydroxybutyrate in plasma during d 1 to 10 postpartum than did other breed and treatment combinations. Cows fed RPC tended to have greater serum triglycerides prepartum (17.0 vs. 14.7 mg/dL) and lower plasma phospholipid at parturition (65.2 vs. 78.1 mg/dL) than control cows. Treatment did not affect cholesterol and phospholipid at other time points, but concentrations followed patterns of dry matter intake pre- and postpartum. Cows were in moderate body condition score (mean = 3.3) at the start of the study and did not lose excessive condition by 3 wk postpartum (mean body condition score loss = 0.5); therefore, cows might not have been at great risk for hepatic lipid accumulation. Additionally, calculated Met balance was negative postpartum; supplemental RPC might not have spared enough Met to produce a physiological benefit. More research is needed to determine how choline affects prevention or alleviation of fatty liver syndrome and to confirm potential differences between Holstein and Jersey cows.     

正相色谱法测定大豆磷脂中的磷脂酰胆碱

目的建立正相色谱法测定大豆磷脂中磷脂酰胆碱含量,用于大豆磷脂类保健食品生产过程中该物质含量的测定和质量控制。方法采用硅胶柱(4.6 mm×250 mm,5.0μm)进行分离;色谱条件为流动相:异丙醇:正己烷:蒸馏水=70:16:14(V:V:V),等度洗脱,流速:1.0 m L/min;柱温:40℃;进样量:10μL;检测波长:205nm;并进行方法学验证,考察方法检测限、精密度、回收率等指标。结果磷脂酰胆碱峰面积与其浓度呈良好的线性关系,线性范围为0.1~0.8 mg/m L(r=0.9999),检出浓度0.04μg/m L,检出限为20μg/g,定量限为66.666μg/g,精密度(RSD)为0.6%,平均回收率99.37%(n=9)。结论本文建立的方法灵敏度高,重复性好,且具有很好的专属性,能够应用于大豆磷脂类保健食品中磷脂酰胆碱含量的检测。