摘要
本研究拟通过共培养乳酸链球菌与酿酒酵母解除产物抑制效应,并将泡沫分离耦合于微胶囊固定细胞发酵强化乳链菌肽(Nisin)的生产。采用液芯微胶囊固定乳酸链球菌和酿酒酵母细胞,并对海藻酸钠和壳聚糖浓度进行优化。结果表明,以乳糖为底物碳源,乳酸链球菌与酿酒酵母的初始接种比例102:1时,共培养发酵液中Nisin效价高达3436.3 IU/mL。海藻酸盐-壳聚糖-海藻酸盐(ACA)液芯微胶囊的制备条件为海藻酸钠浓度15 g/L和壳聚糖浓度5.5 g/L。在微胶囊固定细胞发酵与泡沫分离耦合时间为21 h,分布器孔径180μm,气体体积流率40 mL/min条件下,Nisin的富集比和回收率分别为5.8和63.1%,总效价为3973.2 IU/mL。本研究建立的双菌微囊化发酵-泡沫分离耦合工艺能够有效解除产物抑制和菌体细胞损失,为高密度、连续发酵生产Nisin奠定了理论基础。
This work was aimed at strengthening Nisin production by coupling foam fractionation with microcapsule cells fermentation,in which Lactococcus lactis subsp.lactis(L.lactis)and Saccharomyces cerevisiae(S.cerevisiae)were co-cultivated to relieve the product inhibition from lactic acid.The concentrations of sodium alginate and chitosan were optimized to prepare liquid-core microcapsules for immobilizing L.lactis and S.cerevisiae.Results indicated that the Nisin titer in co-cultivation fermentation broth was as high as 3436.3 IU/mL by using lactose as carbon source and setting initial inoculation ratio of L.lactis and S.cerevisiae at 102:1.The optimal preparation conditions of sodium alginate/chitosan/sodium alginate(ACA)liquid-core microcapsules were sodium alginate concentration of 15 g/L and chitosan concentration of 5.5 g/L.Under the suitable conditions of foam fractionation coupled with microcapsule cells fermentation after cultivation for 21 h,pore diameter of gas distributor 180μm and volumetric air flow rate 40 mL/min,the enrichment ration and recovery percentage of Nisin reached 5.8 and 63.1%,respectively.The total yield of Nisin in fermentation broth was 3973.2 IU/mL.The coupling technology of microcapsule cells immobilizing two strains fermentation and foam fractionation could effectively overcome the obstacles of product inhibition and strain cell loss,thus facilitating the high-density and continuous fermentation for Nisin production.
作者
周静萍
刘伟
杨春燕
殷昊
卢珂
ZHOU Jingping;LIU Wei;YANG Chunyan;YIN Hao;LU Ke(School of Chemical Engineering,Hebei University of Technology,Tianjin 300131,China)
出处
《食品工业科技》
CAS
北大核心
2021年第17期179-186,共8页
Science and Technology of Food Industry
基金
河北省自然科学基金青年项目(B2020202070)。
关键词
乳链菌肽
共培养发酵
ACA液芯微胶囊
细胞固定化
发酵-泡沫分离耦合
乳酸链球菌
酿酒酵母
Nisin
co-cultivation fermentation
ACA liquid core microcapsule cells
cell immobilization
coupling technology of fermentation and foam fractionation
Lactococcus lactis
Saccharomyces cerevisiae
