Department of Aquaculture, National Taiwan Ocean University, Keelung 20248, Taiwan.
J Sci Food Agric. 2012 May;92(7):1562-9. doi: 10.1002/jsfa.4743. Epub 2011 Dec 16.
The polysaccharides of Spirulina platensis possess many biological functions. Reproducing the conditions under which S. platensis produces polysaccharides is critical to furthering our understanding of the function of these polysaccharides for commercial mass production. The changes in microalgal polysaccharide production were studied under greenhouse and laboratory conditions using varying light intensities, temperatures, and NaCl concentrations.
The polysaccharide yield was positively correlated with culturing under 192 µmol photons m(-2) s(-1) light intensity at 38 °C or in 0.75 mol L(-1) NaCl. However, NaCl reduced the total biomass productivity of S. platensis. To mitigate the negative effects of environmental stress on maximal polysaccharide production, we proposed a two-stage culture method. The first stage, designed to increase biomass production, involved culturing under 96 µmol photons m(-2) s(-1) light intensity at 28 °C. Following this, on achieving maximum biomass production, the second stage, designed to stimulate polysaccharide production, involved culturing under 192 µmol photons m(-2) s(-1) light intensity at 38 °C for 3 days or in a 0.75 mol L(-1) NaCl medium for 2 days. High-performance liquid chromatographic analysis revealed that S. platensis polysaccharides were composed of various monosaccharides, including glucose, galactose, rhamnose, mannose, fructose, and mannitol.
The two-stage culture can be successfully applied to achieve the goal of polysaccharide mass production. The first stage focuses on rapidly increasing microalgal biomass. The second stage of culture conditions requires modification to maximize polysaccharide yield.
螺旋藻多糖具有多种生物学功能。复制螺旋藻产生多糖的条件对于进一步了解这些多糖的功能以实现商业大规模生产至关重要。本研究在温室和实验室条件下，通过改变光照强度、温度和 NaCl 浓度，研究了微藻多糖生产的变化。
多糖得率与 192 μmol 光子 m(-2) s(-1)光照强度和 38°C 或 0.75 mol L(-1) NaCl 下培养呈正相关。然而，NaCl 降低了螺旋藻的总生物质生产力。为了减轻环境胁迫对最大多糖产量的负面影响，我们提出了一种两阶段培养方法。第一阶段旨在增加生物质产量，在 28°C 下，光照强度为 96 μmol 光子 m(-2) s(-1)下培养。在达到最大生物质产量后，第二阶段设计为在 38°C 下培养 192 μmol 光子 m(-2) s(-1)光照强度 3 天或在 0.75 mol L(-1) NaCl 培养基中培养 2 天，以刺激多糖生产。高效液相色谱分析表明，螺旋藻多糖由葡萄糖、半乳糖、鼠李糖、甘露糖、果糖和甘露醇等各种单糖组成。
两阶段培养可成功应用于实现多糖大规模生产的目标。第一阶段侧重于快速增加微藻生物质。第二阶段的培养条件需要修改以最大化多糖产量。
