12-羟基-9-十八碳烯酸甲酯实验研究

12-羟基-9-十八碳烯酸甲酯是新型增塑剂,热稳定性好,透明度高,毒性小,广泛应用在塑料行业中。文章通过小试实验、中试试制确定了其最佳工艺参数和条件,从而为规模化生产提供依据。     

用紫外可见分光光度法测定共轭亚油酸的含量

采用UV 91 0 0型紫外可见分光光度计,测定了共轭亚油酸、共轭亚油酸甲酯、共轭亚油酸三甘酯在不同浓度时在 2 0 0～ 3 0 0nm的吸光度,绘制出样品在不同浓度时的吸光度曲线,找出适宜的浓度范围;用MicrocalSoftwareOriginVersion 4.0做回归分析,由线性回归给出样品浓度和吸光度的线性关系;利用PEAutosystemXL TurboMass测得样品中共轭亚油酸乙酯的准确浓度,结合回归系数给出了测定样品中共轭亚油酸含量的经验公式.     

2-氯-5-三氟甲基吡啶合成的研究进展

2-氯-5-三氟甲基吡啶是许多药物的关键中间体.因此,对2-氯-5-三氟甲基吡啶的多种合成方法进行了系统的研究及分析.结果表明,以氯化苄为起始原料的合成工艺安全可靠,生产成本低,效率高,污染少,容易工业化等优点,是一条经济可行的路线.     

过渡金属催化的2,3-联烯酸环化合成γ-丁烯酸内酯

γ-丁烯酸内酯是一类具有重要潜在活性的化合物.发展了二价钯催化的2,3-联烯酸和(ω-1)-烯基卤化物的偶联关环反应.反应经过了二价钯催化的氧钯化-碳钯化,重复的去钯氢化/钯氢化及β-脱卤钯化反应.同时还发展了两种联烯之间的二聚环化反应,两分子2,3-联烯酸的反应生成二丁烯酸内酯,2,3-联烯酸与1,2-联烯酮反应则生成呋喃基取代的γ-丁烯酸内酯.     

饲料中多烯酸脂过量的危害性研究

文章阐述了饲料脂肪的理化特点、营养价值、饲料脂肪对动物体脂肪品质的影响、动物饲料中科学添加植物油脂的方法、饲料中多烯酸脂过量的危害性,对科学合理化养殖具有指导意义。     

5-氯-2-(1H-四唑-5-基)苯胺的合成

本文论述了以4-氯-2-硝基苯腈为原料,在Fecl3及Fe粉催化作用下还原生成2-氨基-4-氯苯甲腈,然后在三乙胺盐酸盐的催化作用下与叠氮化钠反应合成5-氯-2-(1H-四唑-5-基)苯胺的过程,产品结构经IR、1HNMR、MS测定得到认证,含量达到99%,收率75%。     

新显色剂5-(5-硝基-4-甲基-2-吡啶偶氮)-2,4-二氨基甲苯的合成及其鉴定

本文主要介绍了硝基吡啶类化合物5-(5-硝基-4-甲基-2-吡啶偶氮)-2,4-二氨基甲苯的合成和鉴定方法。     

1,3-二甲基-5-吡唑酮合成研究

1,3-二甲基-5-吡唑酮是合成医药、农药和染料等的重要中间体.本文通过对其合成原理的探讨,选择合适的溶剂、反应温度等工艺条件,得到一条三废少、温度适中、易于控制的简便的双乙酰化生产工艺.     

Caprine cardiac sarcoplasmic reticulum: Effect of simulated ischemia on membrane structure and Ca<Superscript>2+</Superscript>-ATPase activity

The sarcoplasmic reticulum was isolated and characterized in the pure form from normal caprine (Capra hircus) hearts. Under ischemic condition, fatty acids like palmitic acid, palmitoyl carnitine and oleic acid accumulatein vivo. These are known to have a detrimental effect on membrane components. The effects of simulated ischemia on the Ca²⁺-ATPase were studied using these fatty acidsin vitro at concentrations at which they occurin vivo in the ischemic heart. All three fatty acids inhibited Ca²⁺-ATPase activity. At lower concentrations, palmitoyl carnitine was the most potent, followed by oleic acid while palmitic acid displayed the least potency. Electron microscopy studies with fatty acids showed morphological disruptions in SR vesicles. The decline in Ca²⁺-ATPase activity could be attributed to the change in membrane morphology.     

榆科种子油脂肪酸成分与榆科分类

 22 kinds of seed oils were extracted from 8 genera of the family Ulmaceae in China The seed oils were examined for their characteristics and fatty acid compositions by gas liquid chromatography.  The fatty acid compositions of these oils were found to fall into two classes. Some genera (such as  Ulmus,  Zelkova)  contain  mainly lower saturated acids, in which the chief acid is capric acid 10:0, while the genera (such as Celtis, Pteroceltis, Aphananthe, Trema, Gironniera) contain mainly unsaturat- ed acids, in which the chief acid is linoleic acid  18:2.  Hemiptelea  davidii  (Hance) Planch contain however either certain amount of short-chain saturated acids or higher unsaturated acids, it appears a intermediate genus between the two classes.  According to the component acids we support that the Ulmaceae be split into two subfamilies. The genera arrangement based on the component acids corresponds basically with the view based on mophological characters and flavonoids found in leaves of Ulmaceae, but there are some discrepancies in certain genera, for example, the Aphananthe should beplaced in Celtoid instead of Ulmoid by the present study.     

长期施肥对农田黑土微生物群落的影响

研究不同磷肥处理农田黑土基本理化性质、磷脂脂肪酸、酸（碱）性磷酸酶、微生物量碳或氮等变化规律。结果表明,有机肥-化肥配施明显提高土壤有机质、总氮以及速效氮、磷、钾等养分含量,进而促进微生物量碳、微生物量碳/有机质比值、磷酸酶活力以及各菌群磷脂脂肪酸含量显著增加。长期氮磷钾配施土壤有机质活性严重退化、不利于土壤微生物生长,而单施磷肥或氮磷肥配施对微生物活力与结构影响较小。有机肥处理中单烯不饱和/饱和脂肪酸比值>1,远高于其他化肥处理,可用来指示有机质质量与可用性;而支链/单烯不饱和脂肪酸与单烯不饱和/饱和脂肪酸比值呈极显著负相关,表明G+菌对养分胁迫抗性强于G-菌。磷脂脂肪酸PCA表明,有机肥与化肥处理微生物群落结构显著不同。个别脂肪酸载荷值分析表明,真菌受无机肥施用影响显著;而G+菌更易受有机肥影响。     

均衡营养调和油及其制备方法

每一个单一油品虽然各具特点,但都不能达到均衡营养。该方法制取的调和油既突出各类不饱和脂肪酸比例组成的合理性,即油酸：亚油酸：亚麻酸=5：4：1,又突出产品的营养功能,即其中含有较高的维生素E。该比例组成满足了中国营养学会推荐的单不饱和脂肪酸与多不饱和脂肪酸比例相等的要求,又满足了ω-6多不饱和脂肪酸：ω-3多不饱和脂肪酸=4：1的要求。因此是最理想的调和油。     

Perturbations in Blood Phosphatidylcholine and Sphingomyelin Fatty Acid Composition in a Sample Population of Cigarette Smokers

Docosahexaenoic (DHA) and arachidonic acids (AA) are polyunsaturated fatty acids (PUFAs), major components of brain tissue and neural systems, and the precursors of a number of biologically active metabolites with functions in inflammation resolution, neuroprotection and other actions. As PUFAs are highly susceptible to peroxidation, we hypothesised whether cigarette smokers would present altered PUFAs levels in plasma and erythrocyte phospholipids. Adult males from Indian, Sri-Lankan or Bangladeshi genetic backgrounds who reported smoking between 20 and 60 cigarettes per week were recruited. The control group consisted of matched non-smokers. A blood sample was taken, plasma and erythrocyte total lipids were extracted, phospholipids were separated by thin layer chromatography, and the fatty acid content analysed by gas chromatography. In smokers, dihomo-gamma-linolenic acid, the AA precursor, was significantly reduced in plasma and erythrocyte phosphatidylcholine. AA and DHA were significantly reduced in erythrocyte sphingomyelin. Relatively short term smoking has affected the fatty acid composition of plasma and erythrocyte phospholipids with functions in neural tissue composition, cell signalling, cell growth, intracellular trafficking, neuroprotection and inflammation, in a relatively young population. As lipid peroxidation is pivotal in the pathogenesis of atherosclerosis and neurodegenerative diseases such as Alzheimer disease, early effects of smoking may be relevant for the development of such conditions.     

中国裸子植物分布区的研究(1)——松科植物的地理分布

 松科是裸子植物中最大的科，共有10属，约240种。我国有9属，约119种，其中2属     为我国特有属，67种为特有种。  本文概述了我国松科各属的水平分布和垂直分布规律；对各     属分布区进行了对比分析。除油杉属和松属外，其余各属的分布，既不深入到极为干旱的地     区，也不深入到热带山区。本文提出川西滇北地区是松科大部分属的发展中心，同时讨论了某     些属的分布区的退却变化。本文还认为，在目前该科化石资料不十分充足的条件下，要确定松    科及其各属的起源中心，可能性是不大的。     

A Rare Case of Short-Chain Acyl-COA Dehydrogenase Deficiency: The Apparent Rarity of the Disorder Results in Under Diagnosis

Short-chain acyl-CoA dehydrogenase (ACAD) deficiency is an extremely rare inherited mitochondrial disorder of fat metabolism. This belongs to a group of diseases known as fatty acid oxidation disorders. Screening programmes have provided evidence that all the fatty acid oxidation disorders combined are among the most common inborn errors of metabolism. Mitochondrial beta oxidation of fatty acids is an essential energy producing pathway. It is a particularly important pathway during prolonged periods of starvation and during periods of reduced caloric intake due to gastrointestinal illness or increased energy expenditure during febrile illness. The most common presentation is an acute episode of life threatening coma and hypoglycemia induced by a period of fasting due to defective hepatic ketogenesis. Here, the case of a 4 month old female patient who had seizures since the third day of her birth and persistent hypoglycemia is described. She was born to parents of second degree consanguinity after 10 years of infertility treatment. There was history of delayed cry after birth. Metabolic screening for TSH, galactosemia, 17-OHP, G6PD, cystic fibrosis, biotinidase were normal. Tandem mass spectrometric (TMS) screening for blood amino acids, organic acids, fatty acids showed elevated butyryl carnitine (C4) as 3.40 μmol/L (normal <2.00 μmol/L), hexanoyl carnitine (C6) as 0.92 μmol/L (normal <0.72 μmol/L), C4/C3 as 2.93 μmol/L (normal <1.18 μmol/L). The child was started immediately on carnitor syrup (carnitine) 1/2 ml twice daily. Limitation of fasting stress and dietary fat was advised. Baby responded well by gaining weight and seizures were controlled. Until now, less than 25 patients have been reported worldwide. The limited number of patients diagnosed until now is due to the rarity of the disorder resulting in under diagnosis.     

家蚕雌蛾体中微量元素和脂肪酸的分析

分析了家蚕雌蛾体中微量元素和脂肪酸的含量,并对其质量进行了评价.家蚕雌蛾体富含微量元素,检测的10种常见微量元素的加和量和人体必需宏量元素含量分别为27339.30 mg/kg和26900.00 mg/kg,其中人体需要量较大的4种微量元素(锌、铁、铜和锰)含量高于重要中药资源昆虫芫菁科昆虫蛾体中的含量.并且适合于人体日需要量.家蚕雌蛾体含有丰富的不饱和脂肪酸,其中必需的n-3系列多不饱和脂肪酸亚麻酸含量最高(39.88%),是鸡蛋的40倍和牛奶的38倍,并高于亚油酸含量6.5倍.研究结果显示,家蚕雌蛾是开发保健食品和医药品的优质原料.     

Genes of renin angiotensin system and coronary heart disease

The levels of cytotoxic aldehydic products in different culinary oils, with or without thermal stress, (routine domestic or commercial frying) were determined by thiobarbituric acid method. The results showed that (i) thiobarbituric acid reactivity was much higher in edible oils rich in polyunsaturated fatty acids than those rich in saturated fatty acids or monounsaturated fatty acids, even without thermal stress, (ii) the lipid peroxide levels were in proportion to the duration of thermal stress, (iii) nature of the container used (steel, iron or teflon-coated) had no significant effect on the extent of lipid peroxidation under identical conditions of thermal stress and (iv) thermally stressed oils collected from hotels and roadside caterers contained higher levels of cytotoxic aldehydic products, when compared to oils thermally stressed under domestic frying conditions. These results suggest that dietary ingestion of thermally or autoxidatively stressed polyunsaturated fatty acid rich culinary oils is more harmful compared with those similarly treated oils rich in saturated fatty acids and monounsaturated fatty acids.     

Characteristics of faecal bacterial flora and volatile fatty acids in Min pig,Landrace pig,and Yorkshire pig

BackgroundIn order to study the influence of long-term growth process and evolution environment on intestinal bacteria of different breeds, the intestinal bacteria and volatile fatty acids among the faeces of Min, Landrace and Yorkshire pigs were analysed by Illumina high-throughput sequencing of the 16S-rDNA and gas chromatography.ResultsThe shared core microbiota of Landrace, Yorkshire and Min pig were 1273, accounting for 69.56% of total abundance of organisms. The proportion of Firmicutes in Min pig faeces (57.89%) was significantly higher than that in Landrace and Yorkshire pig faeces (47.01% and 46.40%, respectively) (P < 0.05), but that of Bacteroidetes was exactly opposite. Moreover, Min pig presented more highly efficient membrane transport, environmental adaptation, carbohydrate transport, and metabolism than Yorkshire pig (P < 0.05). The acetic acid/total volatile fatty acid ratio in Min pig was significantly higher than that in Landrace pig (P < 0.05), and the isobutyric acid/ total volatile fatty acid ratio in Min pig was significantly larger than that in Yorkshire pig (P < 0.05). Furthermore, the content of branched chain volatile fatty acids in Min pig was significantly higher than that in Yorkshire pig (P < 0.05).ConclusionsThis study demonstrated that Min pig, as an excellent breed in the cold area of China, possessed special intestinal floral structure compared to the imported pigs in order to satisfy their physiological and metabolic demands, which may influence their characteristics such as resistance to cold, diseases, and crude feeding, and the ability to deposit intramuscular fat.How to cite: Yang Y, Sun C, Li F, et al. Characteristics of faecal bacterial flora and volatile fatty acids in Min pig, Landrace pig, and Yorkshire pig. Electron J Biotechnol 2021;53. https://doi.org/10.1016/j.ejbt.2021.05.002