Lactic acid bacteria are commonly used as protective starter cultures in food products. Among their beneficial effects is the production of ribosomally synthesized peptides termed bacteriocins that kill or inhibit food-spoiling bacteria and pathogens, e.g., members of the Listeria species. As new bacteriocins and producer strains are being discovered rapidly, modern automated methods for strain evaluation and bioprocess development are required to accelerate screening and development processes. In this study, we developed an automated workflow for screening and bioprocess optimization for bacteriocin producing lactic acid bacteria, consisting of microcultivation, sample processing and automated antimicrobial activity assay. We implemented sample processing workflows to minimize bacteriocin adsorption to producer cells via addition of Tween 80 and divalent cations to the cultivation media as well as acidification of culture broth prior to cell separation. Moreover, we demonstrated the applicability of the automated workflow to analyze influence of media components such as MES buffer or yeast extract for bacteriocin producers Lactococcus lactis B1629 and Latilactobacillus sakei A1608. Our automated workflow provides advanced possibilities to accelerate screening and bioprocess optimization for natural bacteriocin producers. Based on its modular concept, adaptations for other strains, bacteriocin products and applications are easily carried out and a unique tool to support bacteriocin research and bioprocess development is provided.

中文翻译：

---

用于表征天然生产者乳酸乳球菌和清酒乳杆菌中细菌素生产的自动化工作流程

乳酸菌通常用作食品中的保护性发酵剂。它们的有益作用之一是产生称为细菌素的核糖体合成肽，其杀死或抑制食物腐败细菌和病原体，例如李斯特菌属的成员。随着新的细菌素和生产菌株的迅速发现，需要用于菌株评估和生物工艺开发的现代自动化方法来加速筛选和开发过程。在这项研究中，我们开发了一种用于筛选和优化产生细菌素的乳酸菌的生物过程的自动化工作流程，包括微培养、样品处理和自动抗菌活性测定。我们实施了样品处理工作流程，通过在培养基中添加 Tween 80 和二价阳离子以及在细胞分离之前酸化培养液，最大限度地减少生产细胞对细菌素的吸附。此外，我们还证明了自动化工作流程的适用性，可用于分析 MES 缓冲液或酵母提取物等培养基成分对细菌素生产者乳酸乳球菌 B1629 和清酒乳杆菌 A1608 的影响。我们的自动化工作流程为加速天然细菌素生产商的筛选和生物工艺优化提供了先进的可能性。基于其模块化概念，可以轻松地适应其他菌株、细菌素产品和应用，并提供支持细菌素研究和生物工艺开发的独特工具。