脱脂微拟球藻酶解工艺优化研究

Optimization of enzymatic hydrolysis process of defatted Nannochloropsis microalgae biomass

为了提高微拟球藻提油后副产物的利用率和附加值,本研究以脱脂微拟球藻为原料,采用酶解破壁法制备微拟球藻浓缩蛋白。以蛋白质含量、回收率及核酸脱除率为评价指标,探究酶添加量、酶解时间、酶解温度、pH和料液比对酶解产物的影响。在单因素实验的基础上,进行正交试验分析,优化酶解工艺条件。结果表明,最佳酶解工艺条件为:酶添加量1.5%、酶解温度55℃、酶解时间3h、pH 6.0。在此条件下,微藻蛋白质含量达到84.47±0.48%。显微镜镜检、还原糖浓度测定及扫描电镜分析显示,酶处理后微藻细胞壁得到了有效破碎。

In order to improve the utilization rate and added value of the by-products after oil extraction from Nannochloropsis sp.,the raw material of defatted Nannochloropsis sp.was used to prepare Nannochloropsis concentrated protein by enzymatic hydrolysis method.Using the protein content,recovery rate and nucleic acid removal rate as evaluation indices,the effects of enzyme addition,enzymatic hydrolysis time,enzymatic hydrolysis temperature,pH value and solid-liquid ratio on the enzymatic hydrolysis products were explored.On the basis of single factor experiment,orthogonal experiment analysis was carried out to optimize the enzymatic hydrolysis process conditions.The results showed that the optimal enzymatic hydrolysis process conditions were as follows:1.5% of enzyme addition,55℃ of enzymatic hydrolysis temperature,3h of enzymatic hydrolysis time,6.0 of pH;under these conditions,the content of microalgal protein reached 84.47±0.48%.In addition,the microscopic examination,the determination of reducing sugar concentration and the analysis of scanning electron microscope showed that the microalgae cell wall was effectively broken after enzyme treatment.