凝結(jié)芽孢桿菌液體分批發(fā)酵的動(dòng)力學(xué)方程構(gòu)建?

摘 要：采用20 L發(fā)酵罐平臺(tái)對飼用凝結(jié)芽孢桿菌W-02菌株進(jìn)行分批發(fā)酵，實(shí)時(shí)監(jiān)測發(fā)酵液的溶氧含量、吸光度、pH值、活菌數(shù)和可溶性總糖含量，在此基礎(chǔ)上采用Logistic方程和Luedeking-Piret方程分別擬合了菌體生長和可溶性總糖消耗的動(dòng)力學(xué)方程，獲得了該菌株分批發(fā)酵的動(dòng)力學(xué)方程模型和參數(shù)。結(jié)果表明：菌體生長模型為；可溶性總糖消耗模型為；2個(gè)模型計(jì)算的模擬值與驗(yàn)證試驗(yàn)的試驗(yàn)值擬合度均較好，平均相對誤差均小于10%。該結(jié)果為凝結(jié)芽孢桿菌實(shí)際生產(chǎn)中發(fā)酵過程自動(dòng)化監(jiān)測和實(shí)時(shí)控制提供了依據(jù)。

關(guān)鍵詞：凝結(jié)芽孢桿菌；液體分批發(fā)酵；菌體數(shù)；可溶性總糖；動(dòng)力學(xué)方程

中圖分類號：TQ920.6 文獻(xiàn)標(biāo)識碼：A 文章編號：1006-060X（2023）03-0001-05

Abstract： Bacillus coagulans strain W-02 was fermented in batches in 20 L fermentor. During the fermentation process， the dissolved oxygen， absorbance， pH value， viable bacterium count， and soluble total sugar content were measured in real time. Thereafter， the Logistic equation and Luedeking-Piret equation were employed to respectively fit the dynamics of bacterium growth and soluble total sugar consumption. The kinetic models and parameters describing the batch fermentation process were obtained. The results showed that the bacterial growth model was ， and the model of soluble total sugar consumption was .The analogue values calculated from the obtained two kinetic equations were highly in fit with the experimental values， with average relative errors of less than 10%. The results provide a basis for automatic monitoring and real-time control of fermentation process in actual production of Bacillus coagulans.

Key words：Bacillus coagulans; liquid fermentation in batches; viable bacterium count; soluble total sugar; kinetic equations

微生態(tài)制劑具有維持動(dòng)物腸道微生態(tài)平衡、刺激免疫應(yīng)答、提高動(dòng)物消化吸收能力等功效，是當(dāng)前延緩致病菌耐藥性、降低化學(xué)農(nóng)藥殘留的一種抗生素理想替代品[1-3]。凝結(jié)芽孢桿菌（Bacillus coagulans）是乳酸菌的一種，具有降低腸道pH值和黏膜通透性、調(diào)節(jié)腸道菌群平衡、提高腸道黏膜屏障保護(hù)作用和免疫力等特性[4-5]；同時(shí)，它也是芽孢桿菌的一種，具有抗逆性強(qiáng)、耐高溫、易貯存等獨(dú)特耐受特性[6]。經(jīng)過多年的研究，學(xué)者們對凝結(jié)芽孢桿菌的益生特性和安全性已有較全面的認(rèn)識，而且該菌也被農(nóng)業(yè)農(nóng)村部列入可直接飼用的畜禽飼料添加劑品種名錄[7]。當(dāng)前，對凝結(jié)芽孢桿菌發(fā)酵的研究主要集中在菌株篩選[7]、芽孢形成條件[8-9]、培養(yǎng)基優(yōu)化[10-11]、發(fā)酵產(chǎn)物優(yōu)化[12]、高密度發(fā)酵[13-14]、補(bǔ)料工藝[15]等方面，但對其發(fā)酵動(dòng)力學(xué)的研究還未見報(bào)道。……