附子中脂类生物碱的电喷雾三重四极杆质谱研究

附子是常用的中药药物,其中含有的脂类生物碱是附子中重要的活性成分。为了对附子中脂类生物碱的复杂体系进行快速分析,以附子中脂类生物碱为研究对象,建立一种稳定、高效、可靠的分析方法,本研究利用电喷雾三重四极杆质谱的多种扫描功能（全扫描、子离子扫描、母离子扫描、中性丢失扫描）分析附子中脂类生物碱。脂类生物碱间的差别分两种,其一是由于生物碱骨架不同导致的差别;其二是由于C8位所连接的脂肪酸的不同导致的差别。根据这两种差别,分析出附子中含量最多的4类生物碱骨架以及3类C8位取代脂肪酸,共12种脂类生物碱。三重四极杆质谱的母离子扫描及中性碎片丢失扫描功能用于分析附子中脂类生物碱,扫描速度快、效率高、一次扫描同时确定多种结构,所得结果稳定、可靠。     

夏季大白菜软腐病的生物农药防治

采用块根法及盆栽试验测定了6种药剂对夏季大白菜软腐病的防治效果。块根法试验结果表明：72％农用链霉素1000mg／L、中生菌素2000mg／L、菜丰宁B13000mg／L及丰灵3000mg／L对大白菜软腐病菌的防治效果较好，防效分别为87.72％，81．06％．82．32％和83．17％。并对防效较好的药剂进行盆栽试验，结果表明：丰灵拌种加喷灌的处理对大白菜软腐病的防效最佳，其防效高达82．31％，显著优于其它药剂的防效，是防治夏季白菜软腐病的理想药剂。     

关于合成橡胶改性技术的一些看法

本文论述了合成橡胶的氢化、环化、环氧化、接枝、离子化改性及共混等主要的改性方法。着重介绍了环氧化橡胶、离子化改性制离聚体和动态硫化共混制热塑性弹性体的开发和应用。     

真空软包装榨菜和萝卜热力杀菌工艺研究

研究了杀菌工艺条件对真空包装榨菜和萝卜灭菌效果和感官品质的影响,防腐剂对真空包装榨菜和萝卜贮藏过程中微生物生长和品质的影响。结果表明,榨菜较适灭菌条件为95℃10min或90℃20 min,萝卜较适灭菌条件为85℃20min或90℃10min;加入0.05%苯甲酸钠可以大大延长产品的保质期。     

基于PCR-DGGE方法分析榨菜中乳酸菌群落结构

为了深入了解榨菜中的乳酸菌多样性以及影响因素,以市场销售含有辣椒和不含辣椒两种袋装榨菜为研究对象,测定榨菜中的食盐浓度以及亚硝酸盐含量;通过变性梯度凝胶电泳（denaturing gradient gel electrophoresis,DGGE）法分离榨菜总微生物混合16S rDNA基因V7～V8片段,采用Quantity One软件分析乳酸菌物种丰富度、均匀度及物种多样性指数。结果表明：含辣椒的榨菜食盐浓度和亚硝酸盐含量均略低于不含有辣椒的榨菜;含有辣椒和不含辣椒的榨菜两者间物种多样性指数、丰富度和均匀度无显著差异（P＞0.05）。通过回收DGGE电泳带,经克隆后测定碱基序列、与GenBank库序列对比鉴定,不含有辣椒的榨菜5 条回收聚合酶链式反应（polymerase chainreaction,PCR）-DGGE泳带a、b、c、d、e经鉴定分别与Pediococcus argentinicus CRL 776、Uncultured Lactobacillus sp. isolateDGGE gel band lx12、Uncultured bacterium clone 11.02-12、Uncultured bacterium clone 11.02-9、Uncultured Lactobacillus sp.clone PxSC03相似度为98%、96%、97%、97%、97%。含有辣椒的榨菜4 条回收PCR-DGGE泳带1、2、3、4经鉴定分别与Uncultured Lactobacillus sp.、 Lactobacillus sakei A156、Lactobacillus sakei YY1、Lactobacillus sakei WJ1相似度为96%、97%、98%、97%。研究结果表明辣椒对榨菜中微生物群落结构无显著影响。     

Discerning intra‐tuber differences in textural properties in cooked Solanum tuberosum group Tuberosum and group Phureja tubers

BACKGROUND: The textural properties of potato tubers influence their acceptability and palatability and these properties differ between varieties, groups and progeny. The aim of this study was to compare the textural properties of cooked tubers of Solanum tuberosum group Phureja with those of group Tuberosum. RESULTS: To assess intra‐tuber differences, the textural properties of seven cubes from defined positions along the longitudinal axis of tubers of four Tuberosum group cultivars and three Phureja group lines were tested after cooking using an amended wedge fracture method. Tuberosum group tubers gave consistently higher peak force and work done values during fracture than the Phureja group tubers. Moreover, the values for cubes 1–6 from any tuber were not significantly different and only cube 7, from the stem end, gave higher values. Therefore, the use of any of cubes 1–6 is a valid measurement of the tuber as a whole but the central cube 4 may be most conveniently located. The dry matter content of the cubes did not influence the textural properties of the cubes, which suggested that starch swelling is not the main driving force for textural differences. Total pectin methyl esterase (PME) activity was consistently higher in cubes of the Tuberosum group cultivars over the Phureja group lines. CONCLUSION: The method developed is valid and consistent for assessing textural differences within potato germplasm. The relationship between PME activity and enhanced resistance to fracture suggests that PME may modulate pectin cohesiveness, perhaps through increasing Ca²⁺‐bridges, to provide greater resistance to fracture. Copyright © 2010 Society of Chemical Industry     

Antioxidant capacity and secondary metabolites in four species of Andean tuber crops: native potato (Solanum sp.), mashua (Tropaeolum tuberosum Ruiz & Pavón), Oca (Oxalis tuberosa Molina) and ulluco (Ullucus tuberosus Caldas)

Four species of edible tubers endemic to and domesticated in the Andes, native potato (Solanum sp.), mashua (Tropaeolum tuberosum Ruiz & Pavón), oca (Oxalis tuberosa Molina) and ulluco (Ullucus tuberosus Caldas), were studied for their antioxidant capacity and associated secondary metabolites. The antioxidant capacity was measured using ABTS^? radicals and total phenolics, carotenoids, anthocyanin, betaxanthin and betacyanin content were also characterized. The antioxidant capacity found in the crops studied ranged from 483 to 9800 µg trolox equiv. g^?1, phenolics ranged from 0.41 to 3.37 mg chlorogenic acid equiv. g^?1, anthocyanins ranged from 0.08 to 2.05 mg cyanidin 3‐glucoside g^?1 and carotenoids ranged from 1 to 25 µg β‐carotene g^?1. The content of bioactive compounds was high and variable between crops and within the genotypes studied. In general, mashua tubers showed the highest antioxidant capacity and phenolic, anthocyanin and carotenoid content compared with other crops. Ulluco was the only crop that contained betalains in the acid form of betaxanthins (22–96 µg g^?1) and betacyanins (64 µg g^?1) with no presence of carotenoids or anthocyanins. This is the first publication regarding the antioxidant capacity of and associated secondary metabolites in Andean tubers. This information can be useful in the identification of Andean tubers species and genotypes with potential value as a novel dietary source of antioxidants for food, and also for medicinal use. Copyright © 2006 Society of Chemical Industry     

太子参皂甙提取工艺研究

主要对太子参块茎中皂甙组分的浸提工艺进行了研究。结果表明,太子参皂甙最佳浸提条件为:太子参块茎粉碎后,用10倍水沸腾浸提3次,1h/次,同时超声波处理20min。浸提液经壳聚糖澄清后,对DPPH表现出有较好的抑制活性。     

塑料袋装榨菜的微波杀菌效果研究

榨菜在生产中极易受到细菌的污染，使塑料袋装榨菜发生胖袋和变质。采用微波杀菌处理，能够杀死这些有害细菌，同时又可延长袋装榨菜的保质期。