谷氨酰胺转氨酶对碱溶酸沉法提取南极磷虾(Euphausia superba)蛋白质得率的影响

通过碱溶酸沉法提取了南极磷虾蛋白质,研究了谷氨酰胺转氨酶的应用对蛋白质得率的影响。结果表明:碱溶酸沉法能够较好地回收南极磷虾蛋白质;在酸沉过程中,合理添加谷氨酰胺转氨酶能够提高蛋白质得率约5%。     

高酸值鱿鱼油的精制工艺分析

针对鱿鱼加工废弃物中提取的鱼油酸值高,使其应用受限这一现状,采取先酯化以降低其酸值,后脱酸、脱色、脱臭的方法对其进行精制。研究结果表明,以硫酸氢钠为催化剂酯化过程中各因素的最适条件为:醇酸物质的量比20∶1,催化剂用量8%(W/W),反应时间5h,反应温度80℃,该条件下酯化率可达90%左右。精制后鱼油酸值显著下降,澄清透明呈淡黄色,略带鱼腥味,各项理化指标均达到鱼油的SC/T3502-2000标准的精制鱼油一级要求。应用气相色谱分析精制鱼油的脂肪酸组成,其多不饱和脂肪酸(PUFA)的含量达38.34%,其中C20∶5(EPA)和C22∶6(DHA)的含量分别为11.49%和22.14%。     

乳酸菌发酵米糠产γ-氨基丁酸最适条件的研究

使用乳酸菌发酵米糠,以菌种、菌种添加量、发酵温度、发酵时间为单因素研究其对米糠发酵液中γ-氨基丁酸（GABA）含量的影响,在最适条件下,采用混料设计法,使用混合乳酸菌发酵米糠,以发酵液中GABA含量为指标,确定乳酸菌发酵米糠的最优条件为:在混合菌种嗜热链球菌S1添加量为1.55%,保加利亚乳杆菌L1添加量为1.45%,50℃下发酵米糠14h,发酵液中GABA含量最高,为287.975mg/100g。      

RP-HPLC法测定石榴汁中鞣花酸的含量

目的:建立检测石榴汁中鞣花酸的含量测定方法。方法;采用高效液相色谱法,ArcusEP-C18(250mm×4.6mm,5μm)色谱柱,以甲醇-0.1%TFA为流动相梯度洗脱,流速1.0mL/min,检测波长254nm。结果:鞣花酸0.004～0.064μg之间线性关系良好,平均加样回收率为99.32%。结论:方法精密可靠,可作为检测石榴汁中鞣花酸含量的方法。     

Effect of tanniniferous Terminalia chebula extract on rumen biohydrogenation, ∆(9)-desaturase activity, CLA content and fatty acid composition in longissimus dorsi muscle of kids

Conjugated linoleic acid, a fatty acid found in milk fat and ruminant meat is one of the functional food components. Modifying fatty acid composition so as to increase CLA and other beneficial PUFA/MUFA level and reducing SFA levels might be a key to enhance the neutraceutical and therapeutic value of ruminant-derived food products. In the present experiment, the effect of supplementation of polyphenol rich Terminalia chebula plant extract at different concentrations (1.06 g/kg and 3.18 g/kg of body weight in T1 and T2 groups, respectively) was investigated on fatty acid composition of rumen fluid, plasma, intramuscular fat and Δ9-desaturase activity in longissimus dorsi muscle of crossbred kids. Total MUFA and PUFA content in muscle were enhanced by 25 and 35%, respectively, whereas SFA was reduced by 20% thereby improving the desaturation index. Δ9-desaturase activity also increased by 47% resulting in an enhancement of total CLA content (58.73%) in muscle.     

Simultaneous measurement of total acid content and soluble salt-free solids content in Chinese vinegar using near-infrared spectroscopy

Total acid content (TAC) and soluble salt-free solids content (SSFSC) in Chinese vinegar are 2 important indicators in the assessment of its quality. This paper shows the feasibility to determine TAC and SSFSC in Chinese vinegar by near-infrared (NIR) spectroscopy. Synergy interval partial least square (Si-PLS) algorithm was performed to calibrate the regression model. The number of PLS factors and the number of intervals were optimized simultaneously by cross-validation. The performance of the model was evaluated according to root mean square error of prediction (RMSEP) and correlation coefficient (R) in the prediction set. The optimum Si-PLS model for TAC was achieved with RMSEP = 0.264 g/100 mL and R(p) = 0.9655; the optimum Si-PLS model for SSFSC was achieved with RMSEP = 1.93 g/100 mL and R(p) = 0.9302. The overall results demonstrated that NIR spectroscopy combined with Si-PLS could be utilized to determinate TAC and SSFSC in Chinese vinegar, and NIR spectroscopy has a potential to be used in vinegar industry.     

α-亚麻酸单甘酯的合成工艺研究

在溶剂体系中,以亚麻籽油和甘油为反应底物,Lipozyme435为催化剂,制备富含α-亚麻酸的单甘酯,采用单因素实验与响应面分析法考察了制备过程中底物摩尔比、反应时间、油醇比、加酶量和反应温度对单甘酯得率的影响。结果表明,反应的最佳条件为底物摩尔比（亚麻籽油：甘油）=1：3,油醇比为39.66%,加酶量6.01wt%,反应温度为56.11℃,反应时间为10.48 h。在此反应条件下反应所得产物中单甘酯含量约达71.1%,经检验单甘酯中α-亚麻酸的含量达51.36%。     

响应面优化醋酸菌发酵条件研究

以醋酸菌作为发酵菌株,考察不同乙醇浓度、接种量、发酵温度及转速条件下发酵液的总酸含量,运用响应面优化醋酸菌发酵条件,并显微观察菌体的生长形态。结果表明：最佳发酵条件为温度31℃、转速142r/min、乙醇浓度6.1%vol、接种量4.50%,椭圆和杆状的菌体形态与发酵条件形成了对应。     

橘皮中酚酸的研究进展

酚酸广泛存在于植物中,大量研究表明酚酸具有如抗氧化、抗癌等多种生物活性。橘皮中含有丰富的酚酸,而目前对橘皮酚酸的提取分离等方面的报道很少。本文综述了橘皮酚酸类化合物的理化性质、提取、分离纯化及生物活性的研究新进展。提出了今后橘皮的研究方向和开发前景,为更好地开发利用柑橘提供参考。     

云南野生香薷油对子代小鼠学习记忆功能的影响

本研究旨在探讨云南野生香薷油对子代小鼠学习记忆功能的影响。将昆明种小鼠从受孕第1d开始分为空白对照、阳性对照、低、中、高剂量5个组,用云南野生香薷油灌胃至断乳,断乳d小鼠按孕鼠剂量灌胃至出生49d后做Morris水迷宫实验,之后测定小鼠脑组织神经递质和肝、脑组织的脂肪酸。结果表明,与空白对照组比较,定位航行实验的第5d各组均有统计学意义（P〈0．01）。空间探索实验的阳性对照组有统计学意义（P〈0．05）。脑神经递质TPro、NO、AchE：阳性、中、高剂量组均有统计学意义（P〈0．05）。肝脂肪酸结果中阳性和高剂量组的ALA有统计学意义（P〈0．05）;脑组织脂肪酸结果：高剂量组的油酸和ALA有统计学意义（P〈0．05）。可见,富含α-亚麻酸的香薷油具有部分改善子代小鼠学习记忆的功能,其作用可能与喂养此香薷油使脑组织的TPro升高,NO、AchE降低;肝和脑组织的α-亚麻酸升高有关。