Zn2+及Fe3+对嗜淀粉乳杆菌开放式发酵产乳酸的影响

研究了在餐厨垃圾中接种嗜淀粉乳杆菌进行开放式乳酸发酵(即发酵原料不灭菌)的可行性,探讨了添加Fe3+、Zn2+的发酵体系中相关酶活与代谢产物的关系.结果表明,开放式发酵体系的乳酸产量高于非开放式发酵体系.加Fe3+体系的乳酸脱氢酶活性较高,导致乳酸产量增加(最高达29.5g/L),比未添加微量元素的对照体系增加了24.2%;而加Zn2+体系的乙醇脱氢酶(ADH)活性较高,导致副产物乙醇产量的增加,从而使乳酸产量低于对照体系;添加不同微量元素时嗜淀粉乳杆菌对底物中淀粉的利用率由高到低的顺序为:加Fe3+体系(65.7%) > 对照体系 (38.5%)>Zn2+体系(28.1%).此外,在嗜淀粉乳酸菌的发酵体系中,蔗糖和麦芽糖比乳糖容易降解成葡萄糖,果糖,最终被乳酸菌利用.

The influence of Zn2+ and Fe3+ on lactic acid production by Lactobacillus amylophilus GV6 under open fermentation

This paper studied on the influence of microelements Zn2+ and Fe3+ in the microbial growth metabolism,and confirmed the feasibility of open fermentation in kitchen waste using Lactobacillus amylophilus GV6.In the open fermentation,the added of Fe3+ improved the LDH activity and the lactic acid production arrived to 29.5g/L,this in effect raised 24.2% compared with the condition of without adding any microelements.On the contrary,the added of Zn2+ reduced the activity of ADH,making the the ethanol production accumulated to 6.0g/L,meanwhile,the lactic acid only reached to 17.8g/L.Appropriate amount of Fe3+ could optimize the utilization of starch in the medium,arrive to about 65.7%,which improved 38.5% and 28.1% respectively compared with the conditions of adding Zn2+ and without adding any microelements.Sucrose,maltose,lactose first transformed to glucose and fructose,finally used by Lactobacillus amylophilus GV6.