On the Molecular Selection of Exopolysaccharide-Producing Lactic Acid Bacteria from Indigenous Fermented Plant-Based Foods and Further Fine Chemical Characterization

Round 1

Reviewer 1 Report

The aim of the manuscript was to present the study on the EPS-producing LAB isolated from different plant foods and to characterize the EPS produced in culture media with different carbon sources. The manuscript is timely and important for food and LAB researchers as well as food manufacturers. In my opinion, the manuscript represents valuable research. However, the manuscript should be slightly improved before the further stages of the publication preparation process are approved for publication. Below I present my comments and suggestions:

·         Section 0 – Please remove this section, it is not needed in the manuscript.

·         Section „1. Introduction” – In my opinion, this section should discuss the EPS-producing LAB and the importance of the EPS-producing LAB in food production (depending on the topic of the journal). It would also be valuable to detail the research results on the impact of carbon sources on EPS producing LAB and EPS production rate from LAB.

·         Section „2.1. Fermented foods and drinks” – Please add the information that all fermented foods and drinks used in the experiments did not contain industrial starter cultures but were produced by spontaneous fermentation.

·         Section „2.6.2 Exopolysaccharide synthesis” – Please justify the choice of sugar types for experiments. Are these sugars reflected in the chemical composition of fermented foods?

·         Figure 2 – Please add information on the statistical analysis of the results.

·         Section „3.5. Yield and chemical characterization of exopolysaccharides” – Please add the explanation why the strain L. plantarum ZE2 was chosen for experiments. According to what criteria was the LAB strain selected from all the isolated strains for this research?

·         Section „5. Conclusions” – Please add applications for the practical application of the results obtained. What are the benefits of these research results for food manufacturers? What is the significance of the EPS-producing LAB for food quality? Is EPS always beneficial?

·         The entire manuscript is in need of editorial correction: upper temperature indices, lower indices in chemical formulas, cm3 changes in mL, italicized Latin names, brackets, manner of citation of references, etc.

 

A minor revision of the English language is required.

Author Response

Thanks for your comments and suggestions.
Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Title: The title appears to be informative and concise, clearly conveying the focus of the study. It mentions the subject of the research (fermented foods and EPS-producing LAB) and provides a hint of the scope (strains and carbon source effects). However, it might be helpful to include more specific information about the types of fermented foods and their significance.

Abstract: The abstract provides a succinct overview of the study's objectives, methods, key findings, and conclusions. It effectively introduces the concept of fermented foods, EPS production, and strain selection. It highlights the importance of carbon sources and briefly summarizes the results. However, it could benefit from a bit more clarity on the specific fermented foods used and their relevance. Additionally, consider providing a sentence about the practical implications of the findings.

Introduction: The introduction provides a comprehensive overview of the importance of fermented foods and the role of lactic acid bacteria (LAB) in their production. It also highlights the significance of exopolysaccharides (EPS) in LAB metabolism. While the introduction covers essential background information, it could benefit from a more focused statement of the research objectives and hypotheses. Additionally, referencing more recent studies (since the knowledge cutoff date) could enhance the relevance and currency of the introduction. To strengthen the introduction, consider elaborating on the importance of studying specific strains and their potential applications in the food industry. Additionally, you could provide a stronger connection between the strains isolated from different foods and the aim of the study.

Materials and Methods: The materials and methods section provides a clear outline of the study's experimental approach. It details the source of LAB strains, their isolation, and molecular identification. The use of liquid culture medium for EPS screening is justified, and the rationale for temperature and pH selection is well-explained. To enhance this section, consider including more specific details about the composition of the nutrient medium used and the procedures for DNA extraction and sequencing. The section could benefit from more clarity in terms of the sample size, experimental setup, and statistical analysis, which are essential for reproducibility and scientific rigor.

Results: The results section presents the findings of the study in a structured manner, discussing the distribution of LAB species in fermented foods, EPS production, and the impact of different carbon sources. Make sure to include statistical measures of variability for quantitative data, and consider adding appropriate graphs or charts to illustrate trends.

Discussion: The discussion section offers a comprehensive analysis of the results and places them in the context of existing literature. It effectively highlights the significance of the findings, such as the high EPS yield potential of certain strains and the influence of carbon sources. To further improve the discussion, consider addressing the following points:

-          Provide more in-depth interpretation of the specific biological and health implications of high EPS yields, especially related to the strains isolated from fermented foods.

-          Discuss potential limitations of the study, such as the restricted focus on a particular strain and the need for further investigation into other factors affecting EPS production.

-          Compare and contrast your findings with previous studies in more detail, especially in terms of EPS composition and yield under different conditions.

Conclusion: The conclusion provides a concise summary of the key findings and their implications. It also highlights the importance of considering strain specificity and cultivation objectives when selecting carbon sources. To enhance the conclusion, consider adding a brief statement about the broader significance of the study's results for the food industry, health-related applications, or further research directions.

Furthermore, it is recommended to thoroughly proofread the manuscript for potential grammar, punctuation, and typographical errors. These aspects play a pivotal role in ensuring the clarity and professionalism of the content. Proper grammar and punctuation enhance the manuscript's readability, and accurate spelling and typographical consistency contribute to a polished presentation.

Author Response

Thanks for your comments and suggestions.
Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

I thank the authors for correcting the manuscript according to my suggestions and questions. I have no further comments on the manuscript and accept the current version for further processing by the editorial board of the journal.