O R I G I N A L A R T I C L E Open Access© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. Khakpour et al. AMB Express (2024) 14:47 https://doi.org/10.1186/s13568-024-01704-5 for many years. Through the processing of foods such as dairy products, sourdough, and fermented meats, the cell walls of beneficial microorganisms are broken down, allowing the resulting metabolites to enter the food (Leyva Salas et al. 2017). However, recent studies are focused on engineer this implied process it to enable the large-scale production of metabolites derived from beneficial food-grade microorganisms. These metabolites hold promise for a wide range of applications in nutri- tion, healthcare, and various industrial purposes (Udaya- kumar et al. 2022). These postbiotics are the by-products of beneficial microorganisms, often produced by lactic acid bacteria (LAB). They consist of various intracel- lular and extracellular compounds, including vitamins, antimicrobial proteins, bioactive peptides, and bacterial Introduction The emergence of the postbiotic concept is an end to the concerns among researchers regarding the limitations associated with the use of probiotics in food. Moreover, it signifies the advent of a new era in the food industry and the development of biological preservatives. While this concept has been several years old, its recent explo- ration has unveiled new dimensions (Sharafi et al. 2023). Fermented products have been consumed by humans AMB Express *Correspondence: Amir Salari a-salari@um.ac.ir 1Department of Food Hygiene and Aquaculture, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran Abstract The postbiotic derived from Lactiplantibacillus plantarum bacteria was produced in three culture media: milk, MRS, and whey, and its antibacterial and antifungal properties were evaluated. To investigate the production efficiency of postbiotics, three methods, heating, sonication and centrifugation, were utilized to prepare postbiotics in MRS broth culture medium. The antibacterial potency of the postbiotic was evaluated using the agar well-diffusion method, and MIC and MBC tests were conducted for different treatments. The results of the study showed that the postbiotic prepared in food environments such as milk and cheese whey can have antibacterial and antifungal properties similar to the postbiotic prepared in the MRS culture medium. However, it is possible to enrich food matrices such as milk and cheese whey and make further adjustments in terms of pH settings. Additionally, the thermal process was able to create a nanoscale postbiotic, which is a significant achievement for the application of postbiotics in the food and pharmaceutical industries. The future outlook of postbiotics clearly indicates that the emergence of this generation of probiotics can have an attractive and functional position in the food and pharmaceutical industries. Therefore, future research focusing on this subject will contribute to the development of this generation of postbiotics.

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