Application of Saccharomyces cerevisiae var. boulardii for Biological Detoxification of Chemical Contaminants in Foods: A Comprehensive Review

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This review article provides a comprehensive, up-to-date, and valuable synthesis of the potential of Saccharomyces cerevisiae var. boulardii, a probiotic yeast, to biologically detoxify chemical contaminants in foods, including mycotoxins, pesticides, heavy metals, and packaging migrants. Given the limitations of conventional detoxification methods, the topic is of high relevance for food safety and sustainability. The manuscript successfully integrates existing literature, clearly explains the underlying mechanisms, and presents a well-structured and practical roadmap for future research. In particular, the “Future Perspectives” section offers original and forward-looking ideas that meaningfully advance the field.

The paper does not present any major issues requiring substantial revision; however, it could be further strengthened through minor revisions and clarification of certain sections. I recommend addressing the following points:

• Table 1 summarizes the physiological and genetic differences between S. boulardii and S. cerevisiae. However, the direct connection between these differences and their detoxification capabilities has not been fully established.
  Suggestion: Add a short explanatory paragraph below the table to clarify how these features (e.g., optimal growth at 37 °C, acid tolerance, increased FLO gene copy number) contribute to its superior probiotic and detoxification potential.

• The English is generally fluent and clear; however, a few minor grammatical errors and repetitive expressions are present.

  • Page 2: “...motivating a shift toward biological strategies.” → “...motivating a shift towards biological strategies.”

  • Page 5: “The mechanisms of S. cerevisiae var. boulardii in food decontamination is described...” → “...are described...”

  • Throughout the text, the terms “decontamination” and “detoxification” appear to be used interchangeably. Consistency in terminology is recommended.

• The Introduction section begins with rather general information about food safety. The first one or two paragraphs could be shortened to focus more directly on the unique role of S. boulardii and the specific aim of this review.

Author Response

Point-by-point responses to the reviewer's comments

Reviewer 1:

Comment: This review article provides a comprehensive, up-to-date, and valuable synthesis of the potential of Saccharomyces cerevisiae var. boulardii, a probiotic yeast, to biologically detoxify chemical contaminants in foods, including mycotoxins, pesticides, heavy metals, and packaging migrants. Given the limitations of conventional detoxification methods, the topic is of high relevance for food safety and sustainability. The manuscript successfully integrates existing literature, clearly explains the underlying mechanisms, and presents a well-structured and practical roadmap for future research. In particular, the “Future Perspectives” section offers original and forward-looking ideas that meaningfully advance the field.

Response: Thank you very much for your constructive comments and suggestions. The authors hope they have now integrated all your comments and suggestions as highlighted in yellow in the revised version of the manuscript.

Comment: The paper does not present any major issues requiring substantial revision; however, it could be further strengthened through minor revisions and clarification of certain sections. I recommend addressing the following points:

Comment: Table 1 summarizes the physiological and genetic differences between S. boulardii and S. cerevisiae. However, the direct connection between these differences and their detoxification capabilities has not been fully established.

Suggestion: Add a short explanatory paragraph below the table to clarify how these features (e.g., optimal growth at 37 °C, acid tolerance, increased FLO gene copy number) contribute to its superior probiotic and detoxification potential.

Response: Thank you for your valuable insights. The authors have revised this issue for the Table 1.

Comment: The English is generally fluent and clear; however, a few minor grammatical errors and repetitive expressions are present.

• Page 2: “...motivating a shift toward biological strategies.” → “...motivating a shift towards biological strategies.”
• Page 5: “The mechanisms of  cerevisiaevar. boulardii in food decontamination is described...” → “...are described...”
• Throughout the text, the terms “decontamination” and “detoxification” appear to be used interchangeably. Consistency in terminology is recommended.

Response: The authors thank the reviewer for their constructive comments. The grammatical errors were addressed, and wherever applicable, the decontamination term was replaced with detoxification, all modifications were highlighted in yellow in the revised version of the manuscript.

Comment: The Introduction section begins with rather general information about food safety. The first one or two paragraphs could be shortened to focus more directly on the unique role of S. boulardii and the specific aim of this review.

Response: The authors thank the reviewer for their constructive suggestion, this section was fully revised per your kind suggested and highlighted in yellow in the revised version of the manuscript.

 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript provides a broad and timely review of the potential of Saccharomyces cerevisiae var. boulardii as a biocontrol and detoxification agent for food contaminants, including mycotoxins, pesticides, packaging migrants, and potentially toxic elements. The topic is relevant, and the authors have compiled a wide array of references and studies across different contaminant classes.

However, the manuscript requires substantial revision to improve conceptual clarity, structure, scientific rigor, and critical analysis. In its current form, the article is overly descriptive, lacks critical evaluation of conflicting findings, includes several logical gaps, has inconsistently presented data, and sometimes overstates the available evidence.

 

Major points:

While the manuscript claims to offer a “comprehensive” review (line 3–4), it mainly compiles previous studies without synthesizing them into a coherent conceptual framework. The review lacks:

• A critical comparative evaluation of S. boulardii versus other microorganisms (e.g., LAB, other Saccharomycesstrains).Especially since the authors claim, that „rapid, reversible adsorption of contaminants mediated by the architecture of the yeast cell wall“, but all S. yeasts have comparable cell wall, therefore ist no feature of the one strain.
• A structured discussion of limitations (reversibility of adsorption, strain specificity, lack of in-food validation).
• Integration of mechanistic insights with practical application scenarios.

 

A significant proportion of cited studies relate to physiological protection in animal models (for example toxicity mitigation in rats or piglets), not actual food decontamination applications, like the title is indicating.
Examples: Acetamiprid and imidacloprid work in Wistar rats; BPA/phthalate protective effects; Arsenic mitigation in rats. These are not food detoxification studies, but biological protection studies, but dont fit into the scope, indicated in the title.

 

The manuscript briefly mentions heterogeneity (line 266–267) but does not sufficiently critique like lack of standardized contact times and CFU levels, variations in toxin concentrations or limited real-food residue data.

Units and concentrations inconsistently presented (e.g., μg/g vs % removal) in table 2 (column outcome).

“NS” appears frequently but is not explained in the caption.

In some entries, “strain” is missing.

 

Although the introduction states that regulatory pathways are a knowledge gap (line 26–27), the manuscript does not develop this point. Key missing topics include: EFSA/US FDA regulatory landscape for microbial detoxification agents; GRAS status vs. application limits; safety issues of using viable yeast in food matrices (spoilage, fermentation, CO₂ production) or consumer acceptance concerns

 

Minor points:

The manuscript cites a relatively high number of publications originating from the authors’ own laboratory or close collaborators, particularly regarding AFM1 adsorption, probiotic yeast applications, and mycotoxin occurrence. While these contributions are valuable and relevant, the review would benefit from a broader and more balanced representation of the global literature.

The manuscript itself would benefit from further illustrations, not just one schematic figure.

Comments on the Quality of English Language

While generally readable, the manuscript contains grammatical issues, overly long sentences, and occasional awkward phrasing (e.g., “unduly present in food” (line 197), “co-elimination” (line 102), “bio-decontamination”

Author Response

Point-by-point responses to the reviewer's comments

Reviewer 2:

Comment: The manuscript provides a broad and timely review of the potential of Saccharomyces cerevisiae var. boulardii as a biocontrol and detoxification agent for food contaminants, including mycotoxins, pesticides, packaging migrants, and potentially toxic elements. The topic is relevant, and the authors have compiled a wide array of references and studies across different contaminant classes.

Response: The authors greatly appreciate the reviewer for their positive assessment.

 

Comment: However, the manuscript requires substantial revision to improve conceptual clarity, structure, scientific rigor, and critical analysis. In its current form, the article is overly descriptive, lacks critical evaluation of conflicting findings, includes several logical gaps, has inconsistently presented data, and sometimes overstates the available evidence.

Response: The authors thank you for your constructive comments. They have amended all these possible concerns as highlighted in yellow in the revised version of the manuscript under Section 3, Section 3.1, Section 3.2, Section 3.2, in section 4.

 

Comment:

Major points:

While the manuscript claims to offer a “comprehensive” review (line 3–4), it mainly compiles previous studies without synthesizing them into a coherent conceptual framework. The review lacks:

• A critical comparative evaluation of S. boulardii versus other microorganisms (e.g., LAB, other Saccharomycesstrains). Especially since the authors claim, that „rapid, reversible adsorption of contaminants mediated by the architecture of the yeast cell wall“, but all S. yeasts have comparable cell wall, therefore ist no feature of the one strain.
• A structured discussion of limitations (reversibility of adsorption, strain specificity, lack of in-food validation).
• Integration of mechanistic insights with practical application scenarios.

Response: Thank you. Authors have incorporated comparative evaluation (Section 3), mechanism‑to‑application integration (Section 3.1), structured limitations and heterogeneity (section 3.2) and kept the manuscript format intact with strengthened critical synthesis within the existing sections

 

Comment: A significant proportion of cited studies relate to physiological protection in animal models (for example toxicity mitigation in rats or piglets), not actual food decontamination applications, like the title is indicating.
Examples: Acetamiprid and imidacloprid work in Wistar rats; BPA/phthalate protective effects; Arsenic mitigation in rats. These are not food detoxification studies, but biological protection studies, but dont fit into the scope, indicated in the title.

Response: The authors have retained these studies for completeness and explicitly framing them as post‑ingestion mitigation in the third paragraph (section 3.2) with a one‑line scope note before animal studies.

Comment: The manuscript briefly mentions heterogeneity (line 266–267) but does not sufficiently critique like lack of standardized contact times and CFU levels, variations in toxin concentrations or limited real-food residue data.

Response: Thank you, these were added and highlighted in yellow at the end of Section 3.2 in the revised version of the manuscript.

Comment: Units and concentrations inconsistently presented (e.g., μg/g vs % removal) in table 2 (column outcome).

Response: Thank you. The authors agree with reviewer's comment. To improve clarity while preserving the current table format, we standardized each Outcome entry by explicitly labeling the metric type: Removal: ‘’…%” for percent reductions, binding capacity: ‘’ μg/g” where the study reports capacity instead of percentage, and harmonized decimals, fixed minor typos, and defined “NS” in the caption. All units (μg/g and %) were as original metrics reported in the study cited.

Comment: “NS” appears frequently but is not explained in the caption.

Response: Thank you very much, “NS” was now clarified (NS: Not specified) in the caption

Comment: In some entries, “strain” is missing.

Response: Thank you for addressing, however authors have retained strain identifiers whereever applicable (e.g., RC009; CNCM I‑1079) and shown as “NS” where original sources did not specify, these were highlighted as in yellow in the revised version of the manuscript.

 Comment: Although the introduction states that regulatory pathways are a knowledge gap (line 26–27), the manuscript does not develop this point. Key missing topics include: EFSA/US FDA regulatory landscape for microbial detoxification agents; GRAS status vs. application limits; safety issues of using viable yeast in food matrices (spoilage, fermentation, CO₂ production) or consumer acceptance concerns.

Response: The authors have addressed this and incorporated concise regulatory/safety paragraph (Section 4) in line with EFSA/FDA context, GRAS/QPS, viable vs inactivated formats, sensory/spoilage risk, and practical regulatory pathway elements.

Comment:

Minor points:

The manuscript cites a relatively high number of publications originating from the authors’ own laboratory or close collaborators, particularly regarding AFM1 adsorption, probiotic yeast applications, and mycotoxin occurrence. While these contributions are valuable and relevant, the review would benefit from a broader and more balanced representation of the global literature.

Response: Authors have incorporated further citations, wherever applicable as highlighted in the revised version of the manuscript.

Comment: The manuscript itself would benefit from further illustrations, not just one schematic figure.

Response: Authors have added an additional Figure 1 in the revised version of the manuscript.

Comment: While generally readable, the manuscript contains grammatical issues, overly long sentences, and occasional awkward phrasing (e.g., “unduly present in food” (line 197), “co-elimination” (line 102), “bio-decontamination”

Response:  Authors have fully revised, and wherever found typos or awkward phrasing were removed or modified to more scientific ones.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript has improved substantially, particularly in its structure, mechanistic discussion, and clarification of scope.

Table 1: What is meant by “lower resistance to acidic stress”? Since S. cerevisiae is naturally found in beverage fermentations at pH 3–3.5 anboulardii fully viable under those conditions, this comparison requires quantitative data to substantiate the claim.

The manuscript now contains two different “Figure 1” captions, which should be corrected to avoid confusion. Also revise the in text naming of that figure.

Even with the added scope note, animal-model studies still occupy approximately 40% of Section 3.2, which risks misaligning the manuscript with its stated focus on detoxification in foods.

The manuscript notes that adsorption is reversible, but does not discuss whether desorption may occur during processing, storage, or digestion—a critical concern for industrial applications.

The Future perspectives section introduces broader themes (e.g., CRISPR engineering, omics profiling, regulatory dossiers) that, while interesting, extend beyond the stated focus of the review. Some paragraphs read more like a biotechnology outlook than a food safety review. I recommend shifting this section more directly toward the review’s core scope and guiding question: What is the documented ability of S. boulardii to detoxify contaminants in food-related systems, and what research gaps remain?

Author Response

Reviewer's comments and point-by-point responses

Reviewer 2:

The manuscript has improved substantially, particularly in its structure, mechanistic discussion, and clarification of scope.

Response: The authors greatly appreciate the reviewer for their positive re-assessment.

 

Table 1: What is meant by “lower resistance to acidic stress”? Since S. cerevisiae is naturally found in beverage fermentations at pH 3–3.5 anboulardii fully viable under those conditions, this comparison requires quantitative data to substantiate the claim.

Response: Thank you for this comment. The authors have revised the wording in Table 1 to remove this ambiguous statement and now indicate that the comparison refers only to survival under combined low-pH and bile stress. The corresponding text in the manuscript has also been updated. All modifications were highlighted as yellow in the revised manuscript.

 

The manuscript now contains two different “Figure 1” captions, which should be corrected to avoid confusion. Also revise the in text naming of that figure.

Response: Thanks a lot, to point this mistake out, which is now corrected and revised as highlighted in yellow in revised version of the manuscript.

 

Even with the added scope note, animal-model studies still occupy approximately 40% of Section 3.2, which risks misaligning the manuscript with its stated focus on detoxification in foods.

Response: The authors thank the reviewer for this observation. To address this issue, authors have condensed the animal-model descriptions, removed non-essential physiological detail, and added clarifications, wherever applicable, to limit their role to contextual relevance only. This reduces their overall proportion in Section 3.2 and aligns the section more clearly with the manuscript’s focus on detoxification in foods. These revisions have been completed, as highlighted in yellow, in the revised version of the manuscript.

 

The manuscript notes that adsorption is reversible, but does not discuss whether desorption may occur during processing, storage, or digestion—a critical concern for industrial applications.

Response: The authors thank the reviewer for this comment. A sentence addressing the risk of desorption during processing, storage, and digestion has been added to Section 3.2, as highlighted in yellow in the revised manuscript.

 

The Future perspectives section introduces broader themes (e.g., CRISPR engineering, omics profiling, regulatory dossiers) that, while interesting, extend beyond the stated focus of the review. Some paragraphs read more like a biotechnology outlook than a food safety review. I recommend shifting this section more directly toward the review’s core scope and guiding question: What is the documented ability of S. boulardii to detoxify contaminants in food-related systems, and what research gaps remain?

Response: Thank you for the comment. This section was revised to align more closely with the review’s focus on detoxification in food-related systems, and all revisions were highlighted in yellow in the revised manuscript.

 

Author Response File: Author Response.pdf