用复合乳酸杆菌从鸡蛋壳粉中提取乳酸钙的条件优化

Optimization of Extraction Conditions of Calcium Lactate by Complex-lactobacillus Based on Egg Shell Powder

为加大对废弃蛋壳的资源利用率,提高从蛋壳中提取乳酸钙的产能,将定量的蛋壳粉加入保加利亚乳酸杆菌和醋酸杆菌的复合乳酸菌发酵液中,采用甲基百里香酚蓝微板吸光法测定发酵液中两种复合乳酸菌在不同浓度、不同添加比例、不同发酵酸碱度和不同添加物条件下波长610nm的OD值,并结合钙转化公式计算各试验组乳酸钙含量和乳酸钙的转化率。结果表明:当保加利亚乳酸杆菌和醋酸杆菌在浓度为6×108·m L-1、体积比为1∶3时,钙的转化率为75.38%,高于其他实验组;而当复合乳酸菌发酵液中p H值为6时,钙的转化率达到最高,为75.12%;各种糖底物添加试验结果表明:2%甘露醇对保加利亚乳酸杆菌和醋酸杆菌糖反应活性增强效果较为明显,说明菌液中的复合菌比例、添加糖的种类及初始p H值能够影响保加利亚乳酸杆菌和醋酸杆菌对蛋壳粉的发酵分解率。

In order to increase the resource utilization of waste eggshell and to promote the production of calcium lactate by complex- lactobacillus based on egg shell powder, the fermentation conditions including the concentration and proportion of lactic acid bacteria, pH, and environmental additives were optimized by the comparative experiments using methyl thymol rebounds absorption method via absorbance values 610. Test results showed that the calcium conversion rate was 75.38% higher than other groups as Lactobacillus bulgaricus： Acetobacter spp = 1：3 with the concentration of 6×10^8·mL^-1, and the calcium conversion rate was 75.12% reaching the highest when pH was at 6. The results further indicated that the mannitol could obviously enhance the sugar reactivity of Lactobacillus bulgaricus and Acetobacter spp. These results manifested that the proportion of complex bacteria, sugar and initial pH had a major impact on the fermentation of Lactobacillus bulgaricus and Acetobacter spp using the egg shell powder as calcium source. The present study provides the heoretical and experimental foundation for the fermentation extract of calcium lactate with waste egg shell.