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排序方式: 共有243条查询结果,搜索用时 15 毫秒
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Woon Yong Choi Do Hyung Kang Hyeon Yong Lee 《International journal of molecular sciences》2013,14(6):12205-12221
In this study, the immuno-modulatory and anticancer activities of marine algae, Spirulina maxima grown in deep-sea water (DSW), were investigated. It was found that the extract of S. maxima, cultured in DSW, effectively suppressed the expression of Bcl2 in A549 cells as well as inhibiting various human cancer cells with concentration dependency, which possibly implies that the extracts may play more important roles in controlling cancer cell growth. The secretion of cytokines IL-6 and TNF-α from human B cells was also greatly increased, compared to those of the extract grown in conventional sea-water. The growth of Human Natural Killer (NK) cells in the presence of the extracts from DSW was significantly higher (12.2 × 104 viable cells/mL) when compared to the control (1.1 × 104 viable cells/mL). Based on HPLC analysis, the increase in the biological activities of the extracts from DSW was caused by considerably high amounts of β-carotene and ascorbic acid because the DSW contained high concentrations and good ratios of several key minerals for biosynthesizing β-carotene and ascorbic acid, as well as maintaining high cell growth. 相似文献
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本文考察了维生素B12(VB12)、精氨酸(Arg)和萘乙酸(NAA)三个生长因子对螺旋藻混合营养培养的影响,并对藻体干重(DW)及藻胆蛋白(PCP)的含量进行检测。实验结果表明:VB12对螺旋藻生长以及藻胆蛋白的积累均有较大影响,NAA对螺旋藻生长影响较大,而Arg对螺旋藻中藻胆蛋白含量影响较大;在单因素实验的基础上,利用响应面法(RSM)确定三个生长因子的最佳水平:VB12、Arg和NAA水平配比为0.08、45、0.3mg/L,此时藻体干重与藻胆蛋白含量分别增加了20.2%和31.9%;以VB12、Arg和NAA为自变量,建立了藻体干重和藻胆蛋白为响应值的二次多项式数学模型。 相似文献
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Ana Lucía Morocho Jácome Attilio Converti Sunao Sato João Carlos Monteiro de Carvalho 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(11):1574-1583
BACKGROUND: Fed‐batch culture allows the cultivation of Arthrospira platensis using urea as nitrogen source. Tubular photobioreactors substantially increase cell growth, but the successful use of this cheap nitrogen source requires a knowledge of the kinetic and thermodynamic parameters of the process. This work aims at identifying the effect of two independent variables, temperature (T) and urea daily molar flow‐rate (U), on cell growth, biomass composition and thermodynamic parameters involved in this photosynthetic cultivation. RESULTS: The optimal values obtained were T = 32 °C and U = 1.16 mmol L?1 d?1, under which the maximum cell concentration was 4186 ± 39 mg L?1, cell productivity 541 ± 5 mg L?1 d?1 and yield of biomass on nitrogen 14.3 ± 0.1 mg mg?1. Applying an Arrhenius‐type approach, the thermodynamic parameters of growth (ΔH* = 98.2 kJ mol?1; ΔS* = ? 0.020 kJ mol?1 K?1; ΔG* = 104.1 kJ mol?1) and its thermal inactivation ( kJ mol?1; kJ mol?1 K?1; kJ mol?1) were estimated. CONCLUSIONS: To maximize cell growth T and U were simultaneously optimized. Biomass lipid content was not influenced by the experimental conditions, while protein content was dependent on both independent variables. Using urea as nitrogen source prevented the inhibitory effect already observed with ammonium salts. Copyright © 2012 Society of Chemical Industry 相似文献
109.
从黄化的螺旋藻体中分离出一株溶藻菌ES1,经形态、生理生化、16S rDNA序列分析鉴定为盐单胞菌属(Halomonas sp.)。该菌对螺旋藻有较好的溶解效果,能在24h使螺旋藻絮凝成团、黄化死亡,加入15%体积分数的菌液2d后螺旋藻去除率就可达到70.71%。实验表明,经0.22μm的微孔滤膜过滤,高温、低温灭菌处理的滤液,仍能强烈抑制螺旋藻生长,说明起溶藻作用的是ES1菌株的代谢产物,且该代谢产物在高温121℃和低温-80℃下稳定。ES1菌株生长速度快,对盐、碱有较强的耐受性,并能通过自身代谢产物调节pH至适合其生长的9.2左右,该菌的存在会使螺旋藻在短时间内大量死亡,对螺旋藻的大规模工业化养殖危害极大。 相似文献
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Susana Santoyo Miguel Herrero F. Javier Señorans Alejandro Cifuentes Elena Ibáñez Laura Jaime 《European Food Research and Technology》2006,224(1):75-81
Three different parameters (temperature, solvent, and extraction time) were studied regarding to pressure liquid extraction (PLE) of antioxidant and antimicrobial compounds from Spirulina platensis. Two different antioxidant methods, β-carotene bleaching method and DPPH• (2,2-Diphenyl-1-picrylhydrazyl hydrate) free radical scavenging assay, were used to determine the optimal PLE conditions for antioxidants extraction. The selected conditions were as follows: extraction temperature equal to 115 °C, extraction time equal to 15 min and ethanol as extracting solvent. The main antioxidant compounds found in this extract were identified as zeaxanthin, a myxoxanthophyll-like compound and very polar phenolic compounds. Moreover, antimicrobial activity of different PLE fractions was tested against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 11775, Candida albicans ATCC 60193, and Aspergillus niger ATCC 16404. Data obtained showed the hexane and petroleum ether extracts were slightly more active than ethanolic extracts. As for water extracts, none of them were active against the microorganisms tested. Data indicated that both 115 and 170 °C were the best extraction temperatures conditions in order to optimize the extraction of antimicrobial compounds, whereas 9 min was the optimal extraction time. Besides, C. albicans was the most sensitive microorganism to all Spirulina PLE extracts. 相似文献