摘要
为解决柠檬苦素脱苦问题,筛选了可降解柠檬苦素的菌株并优化该菌株的产酶条件。从多年生橘园的土壤和发酵时期的醋醅中筛选并分离出8株可降解柠檬苦素的菌株,对较好降解柠檬苦素的C-1-5、C-1-2-2、JJ-3菌株进行形态学观察和分子生物学鉴定,在单因素实验的基础上,选JJ-3菌株进行响应面法优化的发酵工艺。筛选得到的8株菌中C-1-5、C-1-2-2、JJ-3菌株的柠檬苦素降解率分别为27%、36%、38%。鉴定C-1-5菌株为纤维菌属(Cellulomonas sp.),JJ-3菌株和C-1-2-2菌株为苍白杆菌属(Ochrobactrum sp.)。单因素优化后C-1-5、JJ-3、C-1-2-2菌株柠檬苦素降解率分别提高至65.90%、72.79%、74.66%。通过响应面试验,JJ-3菌株最佳发酵工艺条件是:pH3.5,温度30℃,氮源为硝酸铵,菌接种量3×10~8 CFU/mL。在此工艺条件下,柠檬苦素降解率为78.90%。优化后的菌株具有较高的降解率,可为柠檬苦素酶的研究提供帮助。
In order to solve the debittering problem of limonin,strains degrading limonin were selected and the enzyme production conditions of the strains were optimized.Eight strains degrading limonin were selected and isolated from the soil of perennial orange orchards and vinegar during fermentation.C-1-5,C-1-2-2,and JJ-3 strains with better limonin degradation rates were identified by morphology and molecular biology.On the basis of single-factor experiments,JJ-3 strain was selected for fermentation optimization by response surface optimization.Among them,C-1-5,C-1-2-2,and JJ-3 strains had relatively high degradation rates of limonin,which were 27%,36%,and 38%,respectively.The C-1-5 strain was identified as Cellulomonas sp.by morphology and molecular biology.The JJ-3 strain and C-1-2-2 strain were identified as Ochrobactrum sp.by morphology and molecular biology.Through the single factor optimization,the limonin degradation rates of C-1-5,JJ-3,and C-1-2-2 strains were increased to 65.90%,72.79%,and 74.66%,respectively.Through the response surface experiment,the optimal fermentation process conditions for JJ-3 were:pH3.5,temperature 30℃,nitrogen source was ammonium nitrate,and the inoculation amount was 3×108 CFU/mL.Under this process condition,the degradation rate of limonin was 78.90%.The strains with optimized fermentation conditions had a higher degradation rate.This study can provide help for the research of enzymes degrading limonin.
作者
朱平平
单杨
夏金兰
聂珍媛
ZHU Ping-ping;SHAN Yang;XIA Jin-lan;NIE Zhen-yuan(Longping Branch,Graduate School of Hunan University,Changsha 410125,China;Hunan Academy of Agricultural Sciences,Changsha 410125,China;Hunan Agricultural Products Processing Institute,Changsha 410125,China;Hunan Province Key Lab of Fruits&Vegetables Storage,Processing,Quality and Safety,Changsha 410125,China;School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China)
出处
《食品工业科技》
CAS
北大核心
2020年第19期112-120,共9页
Science and Technology of Food Industry
基金
长株潭国家自主创新示范区专项(2018XK2006)
湖南省重点领域研发计划(2019NK2041)
省科技创新平台与人才计划(2018TP1030)。
关键词
柠檬苦素
菌株
筛选
发酵条件
响应面优化
limonin
strains
screening
fermentation conditions
response surface optimization