Bioemulsifiers form stable emulsions and lower surface tension between two phases with potent anti-microbial activities. Some applications of bioemulsifier are performed at high temperatures and hence production of bioemulsifiers that are stable at high temperature is required. This study aimed at the production of bioemulsifier by an unexplored bacterial strain isolated from a local hot spring. The parameters tested for bioemulsifier production (emulsification ability, surface tension measurement and product formation) showed that 24 h is the optimal time for the production of bioemulsifier by strain S3 with yield of 1.4 g/l. The logistic growth curve of bacterial strain was analysed and kinetic constants for substrate utilisation and product formation were determined by Luedeking-Piret kinetic models. The bacterial strain S3 was Gram-positive and was classified as a strain of Brevibacillus borstelensis . The specific growth rate of the organism was 0.0096 h −1 with the kinetic rate constants as 11.246 (γ) and 10.626 (δ) for Luedeking-Piret substrate and 3.8423 (α) and − 1.9075 (β) for Luedeking-Piret product. Knowledge of these values will help in estimating the substrate utilisation or bioemulsifier formed at any time point. These studies will also help in understanding internal metabolic fluxes hence rigorous analysis of metabolic pathway of bioemulsan is also performed in this study. Graphical abstract

中文翻译：

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一种能够产生高产生物乳化剂的新型嗜热细菌的分离及其动力学建模方面以及拟议的代谢途径

生物乳化剂在两相之间形成稳定的乳液和较低的表面张力，具有强大的抗微生物活性。生物乳化剂的一些应用是在高温下进行的，因此需要生产在高温下稳定的生物乳化剂。本研究旨在通过从当地温泉中分离出的一种未经探索的细菌菌株生产生物乳化剂。生物乳化剂生产参数（乳化能力、表面张力测量和产品形成）表明，24 h 是菌株 S3 生产生物乳化剂的最佳时间，产量为 1.4 g/l。分析细菌菌株的逻辑生长曲线，并通过 Luedeking-Piret 动力学模型确定底物利用和产物形成的动力学常数。菌株S3为革兰氏阳性，被归类为波氏短杆菌菌株。生物体的特定生长速率为 0.0096 h -1，Luedeking-Piret 底物的动力学速率常数为 11.246 (γ) 和 10.626 (δ)，Luedeking-Piret 产物的动力学速率常数为 3.8423 (α) 和 - 1.9075 (β)。了解这些值将有助于估计在任何时间点形成的底物利用率或生物乳化剂。这些研究也将有助于了解内部代谢通量，因此本研究还对 bioemulsan 的代谢途径进行了严格的分析。图形概要 9075 (β) 用于 Luedeking-Piret 产品。了解这些值将有助于估计在任何时间点形成的底物利用率或生物乳化剂。这些研究也将有助于了解内部代谢通量，因此本研究还对 bioemulsan 的代谢途径进行了严格的分析。图形概要 9075 (β) 用于 Luedeking-Piret 产品。了解这些值将有助于估计在任何时间点形成的底物利用率或生物乳化剂。这些研究也将有助于了解内部代谢通量，因此本研究还对 bioemulsan 的代谢途径进行了严格的分析。图形概要