Effects of Indoor and Outdoor Cultivation Conditions on the Cell Growth and Lutein Accumulation of Thermo-tolerant Desmodesmus sp.F51

在室内培养耐温微藻F51,考察了培养温度、自来水及非灭菌培养基对细胞生长及叶黄素积累的影响,并与50 L柱状光生物反应器户外分批培养情况进行对比.结果表明,藻株在35℃下的生物质产率和叶黄素产率最大,分别为767.5和3.05mg/(L·d).低温培养有利于叶黄素积累,但生长速率减缓.用自来水及非灭菌培养基培养时,藻株无明显的生长抑制及染菌现象,在13.0~27.6℃户外培养温度下,藻株最高生物质产率、二氧化碳固定率和叶黄素产率分别为236.3,444.2和1.17 mg/(L·d).The effects of temperature, local tap-water and culture medium without sterilization on cell growth and lutein production of Desmodesmus sp. F51 were investigated under indoor conditions. Outdoor batch cultivation of Desmodesmus sp. F51 was also investigated in 50 L cylindrical photobioreactor. The results showed that the best biomass productivity [767.5 mg/(L·d)] and lutein productivity [3.05 mg/(L·d)] occurred at a temperature of 35 ℃. A low temperature enhanced the lutein content but reduced cell growth rate. There is no significant growth inhibition and microbiological contamination were observed for Desmodesmus sp. F51 using local tap-water and culture medium without sterilization. Under the outdoor temperature of 13.0~27.6 ℃, the highest biomass productivity, CO2 fixation rate and lutein productivity of 236.3, 444.2 and 1.17 mg/(L·d) were obtained, respectively,.福建省青年科技人才创新基金资助项目(编号:2016J05077);; 福建省教育厅资助项目(编号:JA15077

Study on the Kinetics of L-Tryptophan Adsorption by Ion Exchange Resin

通过静态吸附实验,研究了l-色氨酸在001x7型阳离子交换树脂上的等温吸附和吸附动力学特性。采用动边界模型描述l-色氨酸在该树脂上的交换行为,考察了料液浓度、树脂粒径和温度对交换过程的影响。结果表明,l-色氨酸在001x7型阳离子交换树脂上的吸附等温线符合lAngMuIr等温方程,且随PH降低,树脂的最大平衡吸附量逐渐增大;交换过程的吸附速率随l-色氨酸浓度和温度的升高而增大,但随树脂粒径的增大而减小;离子交换过程的速度控制步骤为颗粒扩散控制。交换过程的反应速率常数k0为1.199x10 5,反应级数为1.7,表观活化能EA为19.94kJ MOl 1,并得到了动力学总方程式。The isothermal adsorption and adsorption kinetics of L-tryptophan by 001×7 cation-exchange resin were studied by static experiments.The Moving Boundary Model was applied to describe the kinetics of the ion exchange process.The effects of experimental conditions including the concentration of L-tryptophan,resin particle diameter and adsorption temperature on the ion exchange process were investigated.The results show that the maximum L-tryptophan adsorption capacity of 001×7 cation-exchange resin increases with decreasing solution pH.It was found that the Langmuir equation fits the adsorption isotherm data best,and the particle diffusion is the rate-limiting step of the adsorption process.The adsorption ratio increases with the increase of L-tryptophan concentration and adsorption temperature,but decreases with the increase of the resin particle diameter.The rate constant of exchange(k0),reaction order() and the apparent activation energy of reaction(Ea) were obtained as follows: k0=1.199×10 5,Ea=19.94 kJ mol 1,and the kinetics equation was obtained too.国家自然科学基金(3107488);福建省自然科学基金(2011J01058);中央高校基本科研专项基金(2011121017

Effect of Nitrate Pulse-Feeding Cultivation on Cell Growth and Cell Composition of Thermo-Tolerant Desmodesmus sp. F51

考察脉冲式添加氮源培养对耐温微藻Desmodesmus sp.; F51细胞生长和细胞组成的影响。结果表明,在脉冲式添加氮源培养过程中,藻株F51的蛋白质含量由(56016)mg/g降低至(45617)mg/g; ,而碳水化合物和油脂含量则分别由(20913)mg/g和(983); mg/g提高至(31012)mg/g和(1204)mg/g。另外,对色素和油脂的具体组成变化进行分析,发现脉冲式添加氮源培养可增强beta-胡萝; 卜素的生物合成,以及促进alpha-胡萝卜素生物转化为叶黄素,同时还可发现叶黄素积累与多不饱和脂肪酸含量变化呈正相关性。而在碳水化合物的具体组成; 分析中,发现碳水化合物为藻株F51主要的储能物质,当脉冲式添加氮源培养时间为3; d时,其葡萄糖占总碳水化合物的质量分数可明显提高至(75.71.4)%。采用脉冲式添加氮源培养策略可明显同时促进藻株F51叶黄素和碳水化合物的生; 产。The aim of the present study was to investigate the effect of nitrate; pulse feeding on the cell growth and cell composition of Desmodesmus sp.; F51. Under nitrate pulse-feeding cultivation, the protein content of; cells of Desmodesmus sp. F51 decreased from(560 16) mg/g to(456 17); mg/g, while the contents of carbohydrate and lipid increased from(209 ; 13) mg/g to(310 12) mg/g and(98 3) mg/g to(120 4) mg/g, respectively.; By investigating the changes in carotenoid, lipid and carbohydrate; compositions, it appeared that nitrate pulse feeding could promote; beta-carotene biosynthesis and enhance the bioconversion of; alpha-carotene to lutein. Lutein accumulation was positively associated; with polyunsaturated fatty acid formation. Desmodesmus sp. F51 tended to; accumulate carbohydrate as an energy storage product after 3 days of; cultivation under nitrate pulse-feeding conditions, and the major; accumulated monosaccharide was glucose(75.7 1.4)%. Therefore, the; nitrate-pulse feeding strategy is a highly promising approach to; simultaneously produce lutein and carbohydrate in Desmodesmus sp. F51.国家自然科学基金应急管理项目; 福建省青年科技人才创新基金资助项目; 福建省海洋高新产业发展专项; 福州市市校(院所)科技合作项

Secretive Expression and Optimized Inducement of Barnase

从解淀粉芽孢杆菌中PCR分别扩增解淀粉芽孢杆菌核糖核酸酶barnase基因及其抑制剂barstar基因,采用将barnase基因置于barstar基因保护下的克隆策略,以pET-22b(+)质粒为基础,构建大肠杆菌分泌型表达质粒.IPTG诱导表达目的蛋白后将培养基蛋白进行SDS-PAGE分析并从诱导温度、IPTG诱导浓度和诱导时间三方面初步优化诱导表达条件.Using PCR method to amplify Bacillus amyloliquefaciens ribonuclease barnase gene and its inhibitor barstar gene from Bacillus amyloliquefaciens. The secretive expression vector is constructed by the strategy of protective clone from plasmid pET-22b(+). After induced by IPTG, a 12 kD target barnase protein can be detected from medium protein by SDS-PAGE analysis. Inducing conditions of temperature, IPTG concentration and inducing time have also been optimized.福建省高等学校新世纪优秀人才支持计划资助项

Optimization of microalgae-based lutein production by a thermo-tolerant Desmodesmus sp. F51

叶黄素是一种重要的初级类胡萝卜素，不仅可作为饲料添加剂广泛应用于水产养殖和家禽饲养，而且还可作为天然着色剂用于食品和化妆品。此外，叶黄素还在预防和缓解一些老年性疾病方面起到重要作用。近年来，随着叶黄素应用的不断开拓，其全球市场需求量正在大幅度增加。目前商业生产的叶黄素主要来源于万寿菊，但其应用受到了叶黄素含量低和生产成本高的限制。相比万寿菊，一些微藻具有较高的叶黄素含量和生物量产率，被认为是一种新兴的叶黄素来源。然而，微藻叶黄素的工业化生产在经济上还不可行，急需进一步降低其生产成本。 本文首先比较了四株耐高温栅藻Desmodesmussp.F2、F32、F44和F51的叶黄素生产情况，发现其...Lutein, one of the main primary xanthophylls, is not only widely used as a feed additive in aquaculture and poultry farming, but also as a natural colorant for cosmetics and food. Lutein may play an important role in preventing or ameliorating the effects of a number of degenerative human diseases. Due to its widespread use, the global lutein market has grown significantly in recent years. Marigol...学位：工学博士院系专业：化学化工学院_工业催化学号：2062011015366

Optimization of the Extraction Conditions of C-phycocyanin from Spirulina platensis Using Response Surface Analysis

藻蓝蛋白具有较高的营养和医用价值,为进一步提高其萃取效率,本研究通过响应曲面(rESPOnSE SurfACE METHOdOlOgy,rSM)的方法,对螺旋藻藻蓝蛋白的萃取条件进行优化.结果表明,萃取时间和萃取温度的交互作用对藻蓝蛋白得率的影响最为显著;而实验所得模型的拟合性较好(r2=0.955 0),得到的最佳萃取工艺条件为:质量浓度为2.0Mg/Ml、萃取时间为37.14H、萃取温度为25.61℃,在此萃取条件下得到的藻蓝蛋白得率为13.66%,较优化前提高了32.8%,与模型预测值13.72%接近.Due to high nutritional and medical values of C-phycocyanin,it is important to improve the efficiency of C-phycocyanin extraction.Optimization of the extraction conditions of C-phycocyanin from Spirulina platensis was studied by the response surface methodology(RSM).The results showed that the interaction between extraction time and extraction temperature had a most significant effect on the extraction efficiency of C-phycocyanin.The mathematical model fit well by aR2 of 0.955 0to optimize C-phycocyanin extraction.The optimization conditions were as follows:a solid-to-liquid ratio of 2mg/mL,extraction time of 37.14h,and extraction temperature of 25.61℃.The obtained C-phycocyanin content was 13.66%under these conditions,which was about 32.8%higher than that obtained under non-optimized conditions and perfectly matched the predicted value(13.72%).海洋公益性行业科研专项(201205020-2