酸法水解绿潮藻生物质及发酵制乙醇的效果

Effect of preparing alcohol with green tide algae biomass by acid hydrolysis

摘要:

以2008年我国沿海暴发的绿潮藻浒苔生物质为原材料，分析了海藻中的营养成分，探讨了温度、时间、酸度、料水比等因子对浒苔生物质硫酸水解的影响，通过4因素5水平正交实验，结果显示温度影响极为显著，其次为酸度、时间、料水比，最终确定水解优化组合条件为：温度90 ℃、时间70 min、硫酸浓度5.0%、料水比4.5%。通过液相色谱法检测水解液中的单糖成分，结果表明浒苔水解液中含有葡萄糖、木糖和鼠李糖，其摩尔比为1.71∶1.00∶1.29。同时确定了5种酵母菌(酵母菌1770、1766、啤酒酵母S1、酿酒酵母S2、酵母菌IwSc1)的生长曲线，在其进入稳定期时进行厌氧发酵，发酵完成后用气相色谱法检测最终产物中的乙醇含量，结果显示酿酒酵母S2效果最好，其乙醇含量为2.1 g/L，乙醇得率为26%，发酵液中葡萄糖浓度由18.26 g/L降至2.38 g/L，利用率达87%。S1、S2、IwSc1主要利用葡萄糖，1770、1766可以利用葡萄糖和木糖。

Abstract:

In summer of 2008, green tides broke out in south Yellow Sea.First,the nutrition of floating algae was analyzed and then the algae were treated by sulphuric acid for getting reducing sugar. The effects of temperature(℃), treating time(min), sulphuric acid concentration(%), ratio of mass weight(%)on the biomass hydrolyzation were studied and the hydrolysis conditions were optimized by orthogonal analysis. The results showed that optimum conditions for floating Ulva prolifera biomass hydrolysis by sulphuric acid were 90 ℃ of treating temperature, 70 min of treating time, 5% of sulphuric acid concentration, 4.5% of ratio of the mass weight. Liquid chromatography analysis showed that the molar ratio of monosaccharides in hydrolyzate were glucose 1.71∶xylose 1.00∶rhamnose 1.29. Growth curves of five yeasts(IwSc1,S1,S2,1770,1766) were drawn in order to ferment the liquid at stationary phase.The results showed that S2 was the best for getting highest ethanol concentration with GC analysis. The ethanol concentration was 2.1 g/L and the ethanol conversion rate was 26%.Glucose concentration dropped from 18.26 g/L to 2.38 g/L and the utilization rate of it was 87%. S1, S2 and IwSc1 mainly use glucose compared with 1770,1766 which can use both glucose and xylose.