摘要
探究并提高实验室保藏的分离自新疆酸马奶的乳酸乳球菌KLDS4.0325的产叶酸能力。首先基于实验室前期对KLDS4.0325的全基因组测序结果,对其在基因水平表现出的产叶酸能力进一步运用高效液相色谱法进行测定。然后,以叶酸产量为响应值,通过响应面法对发酵条件进行优化,确定最优发酵条件。利用单因素试验,确定最佳氮源为酵母浸粉,最佳碳源为葡萄糖,主要影响因素为初始pH值、对氨基苯甲酸(p-aminobenzoic acid,pABA)添加量、谷氨酸添加量与温度。通过Box-Behnken响应面试验,确定最优发酵条件为初始pH 5.40、pABA添加量42.0 mg/L、谷氨酸添加量6.30 g/L、温度35.40℃,在此条件下叶酸产量为0.814μg/mL,是优化前(0.260μg/mL)的3.13倍。通过对乳酸乳球菌KLDS4.0325培养基成分及发酵条件的优化,得出该菌株产叶酸的最优培养基成分及发酵条件,为天然叶酸的产业化生产与应用提供了理论支持。
This study aimed to select and optimize the critical medium components and fermentation conditions for the production of folate by Lactococcus lactis KLDS4.0325,isolated from koumiss in Northwest China’s Xinjiang.Folate content in the fermentation broth of this strain was determined by high performance liquid chromatography(HPLC).Using one-factor-at-a-time(OFAT)method,yeast extract and glucose were identified as the optimal nitrogen and carbon sources,respectively,and initial pH,the concentration of p-aminobenzoic acid(pABA)and glutamic acid and culture temperature were identified as main factors that influence folate production.The levels of the four factors were further optimized using response surface methodology with Box-Behnken design.The optimal values for initial pH,pABA concentration,glutamic acid concentration and fermentation temperature were determined as 5.40,42.0 mg/L,6.30 g/L and 35.40℃,respectively.Under these conditions,the yield of folic acid was 0.814μg/mL,which was 3.13 times higher than that(0.260μg/mL)before the optimization.This study provides technical support for the industrial production and application of natural folate.
作者
焦雯姝
关嘉琦
史佳鹭
李柏良
陆婧婧
闫芬芬
李娜
占萌
霍贵成
JIAO Wenshu;GUAN Jiaqi;SHI Jialu;LI Bailiang;LU Jingjing;YAN Fenfen;LI Na;ZHAN Meng;HUO Guicheng(Key Laboratory of Dairy Science,Ministry of Education,Northeast Agricultural University,Harbin 150030,China)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2020年第6期123-130,共8页
Food Science
基金
“十三五”国家重点研发计划重点专项(2017YFD0400303)。
作者简介
第一作者:焦雯姝(1995-)(OCRID:0000-0003-2215-4548),女,硕士研究生,研究方向为食品科学。E-mail:JWS775499645@163.com;通信作者:霍贵成(1958-)(OCRID:0000-0002-6875-1834),男,教授,博士,研究方向为食品微生物与生物技术。E-mail:gchuo@126.com。
