甜蛋白Brazzein在毕赤酵母中的表达及应用  

Expression of sweet protein Brazzein in Pichia pastoris and its application

作　　者：孟珊珊 谭明[2] 肖冬光[1] 宋诙[2] MENG Shanshan;TAN Ming;XIAO Dongguang;SONG Hui((Institute of Biological Engineering,Tianjin University of Science and Technology,Tianjin 300457,China;Tianjin Institute of Industrial Biotechnology,Chinese Academy of Sciences,Tianjin 300308,China)

机构地区：[1]天津科技大学生物工程学院,天津300457 [2]中国科学院天津工业生物技术研究所,天津300308

出　　处：《食品与发酵工业》2020年第15期21-26,共6页Food and Fermentation Industries

基　　金：天津市科技计划项目(15YFYSSY00040);天津市合成生物技术创新能力提升行动(TSBICIP-KJGG-006)

摘　　要：巴西甜蛋白(Brazzein)是分离自非洲西部野生植物Pentadiplandra brazzeana Baillon果实中的一种天然高倍甜味蛋白,具有较好的食品应用潜力.利用毕赤酵母GS115对巴西甜蛋白及蛋白二硫键异构酶(protein di-sulfide isomerase,PDI)进行共表达,重组Brazzein在发酵液中分泌表达量为1 g/L.采用超滤-纳滤膜分离系统和冷冻干燥技术开发重组Brazzein的低成本制备工艺,并完成口感评价,甜度倍数为蔗糖的40倍.同时研究了重组Brazzein对常见致病菌和肠道益生菌的体外抑菌性能,结果表明,重组Brazzein对白念珠菌的最低抑菌质量浓度(minimum inhibitory concentration,MIC)为15 mg/mL,对金黄色葡萄球菌的MIC值为7.5 mg/mL,对桧状青霉的MIC值为3.75 mg/mL,对枯草芽孢杆菌、大肠杆菌、干酪乳杆菌、嗜酸乳杆菌和粪肠球菌没有发现明显的抑菌效果.该研究为Brazzein在甜味剂方面的推广应用提供了理论研究基础.Brazzein is a kind of natural high-sweetness protein isolated from the fruit of wild plant Pentadiplandra brazzeana Baillon in western Africa and has good food application potential.Using Pichia pastoris GS115 to co-express Brazzein and protein disulfide isomerase(PDI),the expression of recombinant Brazzein in the fermentation broth was 1 g/L.An ultrafiltration-nanofiltration membrane separation system and freeze-drying technology were used to develop a low-cost preparation process for recombinant Brazzein.The taste evaluation of recombinant Brazzein was conducted.The sweetness of Brazzein was 40 times of sucrose.In vitro antibacterial performance of recombinant Brazzein against common pathogenic bacteria and intestinal probiotics was studied.The results showed that the recombinant Brzezein had a minimum inhibitory concentration(MIC)value of 15 mg/mL against Candida albicans and 7.5 mg/mL against Staphylococcus aureus.The MIC value for Penicillium spis was 3.75 mg/mL and no obvious antibacterial effect was found on Bacillus subtilis,Escherichia coli,Lactobacillus casei,Lactobacillus acidophilus and Enterococcus faecalis.It provides a theoretical basis for the popularization and application of Brazzein in sweetener.

关 键 词：巴西甜蛋白 毕赤酵母GS115 超滤-纳滤膜 抑菌性能 

分 类 号：TS201.3[轻工技术与工程—食品科学]