Application of oxidation-reduction potential in microbial fermentation
Oxidation-reduction potential(ORP),as a highly sensitive fermentation parameter that can monitor the fermentation status in real time,can be applied to fermentation by overcoming the limitations of the application of dissolved oxygen electrodes under microaerobic and anaerobic environ-ments.ORP fluctuations is found to reflect the relative strength of oxidizing or reducing properties in the fermentation broth and are closely related to microbial growth status.Analysis of ORP data determines the growth phases of microorganisms,while regulation of ORP inversely influences gene expression and metabolic activities of microorganisms,providing a promising regulatory pathway for fermentation production.The concept,fluctua-tion principles,and potential microscopic mechanisms of ORP in microbial fermentation were introduced in this paper.Applications of ORP as a non-regulatory parameter in fermentation and advancements in new detection technologies were summarized.The regulation methods,analysis meth-ods,product development,and strains breeding for ORP were mainly expounded,aiming to provide a theoretical foundation for further study of ORP in microbial fermentation.