大气压介质阻挡放电等离子体强化克雷伯氏菌发酵的研究  

Enhanced Fermentation of Klebsiella Pneumoniae Using Dielectric Barrier Discharge Plasma under Atmospheric Pressure

作　　者：董晓宇[1] 刘婷婷[1] 窦少华[1,2] 唐乾[1] 袁玉莲[1] 王晓辉[1] 王仁军[1] 焦鑫艳[1] 郭相金 

机构地区：[1]大连大学生命科学与技术学院,辽宁大连116622 [2]大连理工大学生命科学与技术学院,辽宁大连116024

出　　处：《高校化学工程学报》2015年第4期881-889,共9页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金(21246012;21306015;21476032);辽宁省自然科学基金(201202006)

摘　　要：大气压空气介质阻挡放电等离子体作为一种新型强化微生物发酵方法,用于克雷伯氏菌发酵生产1,3-丙二醇。采用气相色谱法检测1,3-丙二醇浓度;用紫外-可见分光光度计检测代谢关键酶活性;采用荧光分光光度计检测细胞膜通透性。考察不同等离子体处理时间对克雷伯氏菌接种体在2%、4%和6%甘油浓度种子培养基中揺瓶发酵的影响。结果表明,等离子体处理4 min接种体在6%甘油浓度种子培养基中揺瓶发酵,1,3丙二醇浓度达到最大值17.2 g?L-1,比对照组提高89%(9.1g?L-1)。甘油脱氢酶比活性0.19 U?mg-1,甘油脱水酶比活性10.9 U?mg-1,1,3-丙二醇氧化还原酶比活性0.65 U?mg-1,比对照组(0.04,9.2和0.09 U?mg-1)分别提高4.8倍,18%和7倍。6%甘油浓度间歇发酵,等离子体组1,3-丙二醇浓度和生产强度分别为24.6 g?L-1和1.23 g?(L?h)-1,均比对照组提高56%;转化率0.54 mol?mol-1,与对照组相近(0.53 mol?mol-1)。在间歇发酵过程中,等离子体处理组菌体细胞膜通透性显著高于对照组。4%甘油浓度批式流加发酵,等离子体组1,3-丙二醇浓度46.9 g?L-1,转化率0.50 mol?mol-1,生产强度1.51 g?(L?h)-1,转化率和生产强度分别比对照组提高14%和40%。上述结果表明,大气压介质阻挡放电等离子体可以提高克雷伯氏菌生产1,3-丙二醇能力。Dielectric barrier discharge （DBD） plasma under atmospheric pressure is considered as a novel approach to enhance microbial fermentation. In this study, DBD plasma was used to improve Klebsiella pneumoniae fermentation for 1,3-propanediol （1,3-PD） production. The concentration of 1,3-PD was determined by gas chromatography, the key enzyme activities were analyzed using UV-visible spectrophotometer, and the cell membrane permeability was detected by fluorescence spectroscopy. The effects of plasma exposure time on K. pneumoniae fermentation under different glycerol concentrations （2%, 4% and 6%） were investigated in flasks. The results show that under the fermentation condition of 6% glycerol with 4 min application of DBD plasma the obtained 1,3-PD concentration （17.2 g·L^-1） is the highest, which increases by 89% when comparing to the control （9.1 g·L^-1, non-treated K. pneumoniae）. The specific activities of glycerol dehydrogenase, glycerol dehydratase and 1,3-PD oxidoreductase of the samples treated with DBD plasma also increase by 4.8 folds, 18% and 7 folds, respectively. The DBD plasma-treated cells under batch fermentation （6% glycerol） produce 1,3-PD with concentration ot z4.o g.L anu producitivity of 1.23 g·（L·h）^-1, both of which are 56% higher than that of the control, and the 1,3-PD yield is similar as control （0.54 versus 0.53mol·mol^-1）. Moreover, these cells also exhibit a significant increase in membrane permeability. In fed-batch fermentation with 4% initial glycerol concentration, the 1,3-PD final concentration, molar yield and productivity of the DBD treated sample are 46.9 g·L^-1, 0.50 mol·mol^-1 and 1.51 g·（L·h）^-1, respectively, which shows 14% and 40% increases of yield and productivity, respectively. The results indicate that DBD-plasma under atmospheric pressure can improve 1,3-PD production ofK. pneumoniae.

关 键 词：强化发酵:大气压冷等离子体:克雷伯氏菌 1 3-丙二醇 

分 类 号：TQ923[轻工技术与工程—发酵工程]