Recent Applications and Strategies to Enhance Performance of Electrochemical Reduction of CO2 Gas into Value-Added Chemicals Catalyzed by Whole-Cell Biocatalysts
Round 1
Reviewer 1 Report
Comment 1: The abstract should not be like a table of content. The gist of the manuscript is missing in the abstract and hence required to be rewritten. Also add some numerical values/ranges in the abstract, highlighting its novelty.
Comment 2: The full form of the abbreviation used need to be provided the very first time they are used in the text. For ex. NADH. Keywords are OK.
Comment 3: The introduction is very short and poor in the literature review. The author needs to elaborate the introduction section. The author may add the following latest pieces of literature to make the literature richer i.e.,
https://0-doi-org.brum.beds.ac.uk/10.1016/j.seta.2022.102677 , https://0-doi-org.brum.beds.ac.uk/10.1016/j.rser.2022.112916, (in Lines 28-30), and https://0-doi-org.brum.beds.ac.uk/10.1016/B978-0-12-823007-7.00015-8, (in Lines 31-43).
Comment 4: The novelty and significance of the study need to be clearly stated in the last paragraph of the introduction.
Comment 5: “The aim to find another microorganism ….” Lines 84-87
The sentence doesn’t make any sense. The author must check the statement.
Comment 6: The introduction and almost every section of the manuscript look dull to the readers. The author must add some pictorial representations/figures in the manuscript to make it more presentable and interesting to the readers.
Comment 7: The manuscript is poor in the literature review. A lot more literature needs to be added in the different sections apart from the above-suggested pieces, to match the standards of Processes MDPI.
Comment 8: The author need to discuss the different discussions, and not only report the literature. Further, the author should include a concluding statement in each subsection.
Comment 9:
Comment 10: The conclusion should not be like that of abstract. The summarizing results (and concluding statements from each subsection of the experiment) need to be added at the end of the manuscript.
Comment 11: The manuscript needs to be proofread for better clarity and to eliminate grammatical errors.
Comment 12: The author must check and remove references older than a decade.
Author Response
Correction on the comments of Reviewer #1:
Thank you very much for your comments and suggestions. We checked and revised the manuscript following your comments and suggestions as following. We hope that the revised manuscript overcomes the defects. Thank you again for your comments and suggestions.
- Comment 1:
“The abstract should not be like a table of content. The gist of the manuscript is missing in the abstract and hence required to be rewritten. Also add some numerical values/ranges in the abstract, highlighting its novelty.”
Thank you for your comments. We revised abstract in the revised manuscript. We hope that the revised manuscript overcomes the defects.
- Comment 2:
“The full form of the abbreviation used need to be provided the very first time they are used in the text. For ex. NADH. Keywords are OK.”
Thank you for your comment. We checked and added full form of the abbreviations in the first time that they are used in the text.
- Comment 3:
“The introduction is very short and poor in the literature review. The author needs to elaborate the introduction section. The author may add the following latest pieces of literature to make the literature richer.”
Thank you very much for your comment. We added several references relating to the topic and discussed in detail about the topic in each section. We hope that the revised manuscript overcomes the defects. Thank you again for your comment and suggestion.
- Comment 4:
“The novelty and significance of the study need to be clearly stated in the last paragraph of the introduction.”
Thank you for your comment. We revised the introduction section. We hope that the revised manuscript overcomes the defects.
- Comment 5:
“The aim to find another microorganism ….” Lines 84-87
The sentence doesn’t make any sense. The author must check the statement.”
Thank you very much for your comment. We revised the sentence in lines 84-87. We hope that the revised manuscript overcomes the defects.
- Comment 6:
“The introduction and almost every section of the manuscript look dull to the readers. The author must add some pictorial representations/figures in the manuscript to make it more presentable and interesting to the readers.”
Thank you for your comment and suggestion. We inserted figure for the electrochemical reduction of CO2 catalyzed by the whole-cell biocatalyst in introduction section. We hope that the revised manuscript is improved compared to the previous version.
- Comment 7:
“The manuscript is poor in the literature review. A lot more literature needs to be added in the different sections apart from the above-suggested pieces, to match the standards of Processes MDPI.”
Thank you very much for your comment and suggestion. We inserted more references in the introduction part and other sections. We hope that the revised manuscript enhanced compared to the previous version.
- Comment 8:
“The author need to discuss the different discussions, and not only report the literature. Further, the author should include a concluding statement in each subsection.”
Thank you for your comments. We gave more discussion and concluding statement of each subsection in the revised manuscript. We hope that the revised manuscript improved compared to the previous version. Thank you again for your kind comments.
- Comment 9& Comment 10:
“The conclusion should not be like that of abstract. The summarizing results (and concluding statements from each subsection of the experiment) need to be added at the end of the manuscript.”
Thank you for your kind comment. We revised the abstract and inserted summarizing results for each subsection in the revised manuscript. We hope that the revised manuscript improved compared to the previous version.
- Comment 11: “The manuscript needs to be proofread for better clarity and to eliminate grammatical errors.”
Thank you very much for your comments and suggestion. We proofread and revised the manuscript. We hope that the revised manuscript improved compared to the previous version.
- Comment 12:
“The author must check and remove references older than a decade.”
Thank you for your comment. We checked and removed some old references.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript by Tuan Quang Anh Le reviews the use of microorganisms as whole-cell biocatalysts for the electrochemical reduction of CO2 into various value-added chemicals, giving insights at molecular levels, while some strategies to enhance the performance of the electrochemical reduction of CO2 to produce value-added chemicals catalyzed by whole-cell biocatalysts are proposed. The manuscript layout is well-organized, and the author summarizes examples from different sectors. However, a revision needs to be addressed before its publication. Firstly, some references are outdated/not from very recent literature; out of forty-two references, only five of them are published in the last 5 years. Are there no recent works that describe the topic the author focuses on? Moreover, the challenges of using microorganisms as whole-cell biocatalysts for electrochemical reduction of CO2 should be more clearly described. Furthermore, the reader should be familiar with the development and characteristics of electrochemical reduction of CO2 catalyzed by whole-cell biocatalyst before he comes across with examples of such systems. Finally, in the conclusion section, the future aspects of the topic should be discussed.
Author Response
Correction on the comments of Reviewer #2:
Thank you very much for your comments and suggestions. We checked and revised the manuscript following your comments and suggestions as following. We hope that the revised manuscript overcomes the defects. Thank you again for your comments and suggestions.
- Comment 1:.
“Firstly, some references are outdated/not from very recent literature; out of forty-two references, only five of them are published in the last 5 years. Are there no recent works that describe the topic the author focuses on?”
Response 1: Thank you very much for your comments. We added more references published in last five years relating to the topics and described several applications of the electrochemical reduction of CO2 to produce value-added chemicals catalyzed by whole-cell biocatalysts and relating contents that published in last 5 years in the revised manuscript. We hope that the revised manuscript overcomes the defects. Thank you again for your kind comments.
- Comment 2:
“Moreover, the challenges of using microorganisms as whole-cell biocatalysts for electrochemical reduction of CO2 should be more clearly described.”
Response 2: Thank you for your comment. We described more about using microorganisms as whole-cell biocatalysts for the electrochemical reduction of CO2 in the introduction section and other parts. We hope that the revised manuscript is improved compared to the previous version.
- Comment 3:
“Furthermore, the reader should be familiar with the development and characteristics of electrochemical reduction of CO2 catalyzed by whole-cell biocatalyst before he comes across with examples of such systems.”
Response 3: Thank you for your comments and suggestions. We inserted the development and characteristics of the electrochemical reduction of CO2 catalyzed by whole-cell biocatalyst in the introduction part of the revised manuscript. We hope the revised manuscript improved compared to the previous version.
- Comment 4:
“Finally, in the conclusion section, the future aspects of the topic should be discussed.”
- Response 4: Thank you for your comments. We discussed more about the future aspects of the topic in the revised manuscript. We hope that the revised manuscript overcomes the defects.
Author Response File: Author Response.pdf
Reviewer 3 Report
The author presents a review of the Recent Applications and Strategies to enhance the performance of electrochemical reduction of CO2 gas into value-added chemicals catalyzed by whole-cell biocatalysts. The author discusses three main points: (i) the recent application of microorganisms as whole-cell biocatalysts for the electrochemical reduction of CO2 into various value-added chemicals; (ii) some insights at molecular levels of the microorganisms as biocatalysts for the electrochemical reduction of CO2 into value-added chemical; (iii) strategies to enhance the performance of the electrochemical reduction of CO2 to produce value-added chemicals catalyzed by whole-cell biocatalysts.
The topic and perspective that use author are clear and it has relevant contributions, however, in my opinion:
The introduction and the state of the art should be expanded, emphasizing the state of the art in-silico for microorganisms.
Some acronyms are missing, for example, the acronym NADH is missing.
In reference 38, the year is missing.
Author Response
Correction on the comments of Reviewer #3:
Thank you very much for your comments and suggestions. We checked and revised the manuscript following your comments and suggestions as following. We hope that the revised manuscript overcomes the defects. Thank you again for your comments and suggestions.
- Comment 1:
“The introduction and the state of the art should be expanded, emphasizing the state of the art in-silico for microorganisms.”
Response 1: Thank you for your kind comment. We added several references relating to the topic and discussed in detail about the topic in introduction section and other parts as well as described more about in-silico for microorganisms in section 4 “Strategies to enhance performance of microbial electrochemial reduction of CO2 to produce value-added chemicals”. We hope that the revised manuscript overcomes the defects. Thank you again for your comment and suggestion.
- Comment 2:
“Some acronyms are missing, for example, the acronym NADH is missing.”
Response 2: Thank you for your comment. We checked and inserted missing acronyms in the revised manuscript.
- Comment 3: “In reference 38, the year is missing”
Response 3: Thank you very much for your comment. We inserted publication year for reference 38 as follow: “F. Ammam, P.-L. Tremblay, M. D. Lizak and T. Zhang, "Effect of tungstate on acetate and ethanol production by the electrosynthetic bacterium Sporomusa ovata," Biotechnol. Biofuels., vol. 9, p. 163, 2016” in the revised manuscript.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
I think the author hasn’t gone through the suggestions provided in the previous review round and not modified the manuscript accordingly. Apart from the previous comments below are the major concerns that need to be addressed.
Comment 1: The references need to be formatted, it is starting from “[2], and reference [1] is missing.
Comment 2: The author should provide a detailed rebuttal report.
Comment 3: The introduction is very short and poor in the literature review. The author needs to elaborate the introduction section. The author may add the following latest pieces of literature to make the literature richer i.e.,
https://0-doi-org.brum.beds.ac.uk/10.1016/j.seta.2022.102677 , https://0-doi-org.brum.beds.ac.uk/10.1016/j.rser.2022.112916, (in Lines 28-30), and https://0-doi-org.brum.beds.ac.uk/10.1016/B978-0-12-823007-7.00015-8, (in Lines 31-43).
Comment 4: The novelty and significance of the study need to be clearly stated in the last paragraph of the introduction.
Lines 98-103 state that recent studies have been investigated, however, in the review the studies focussed are outdated i.e., more than a decade old (i.e., from 2007, 2010, 2012, 1985, 2009, 2011). Hence the essence of the state-of-the-art review is missing. The older literature needs to be removed and the latest investigations need to be added.
Comment 5: The different sections discussed do not have a flow and connection. The different sections need to be connected.
The sentence doesn’t make any sense. The author must check the statement.
Comment 6: The introduction and almost every section of the manuscript look dull to the readers. The author must add some pictorial representations/figures in the manuscript to make it more presentable and interesting to the readers.
Comment 7: The manuscript is poor in the literature review. A lot more literature needs to be added in the different sections apart from the above-suggested pieces (like a total of 100 references for a review manuscript), to match the standards of Processes MDPI.
Comment 8: The author needs to discuss the different discussions, and not only report the literature. Further, the author should include a concluding statement in each subsection.
Comment 9: The manuscript needs to be proofread for better clarity and to eliminate grammatical errors from a professional/native proofreading service.
Author Response
Correction on the comments of Reviewer #1:
Thank you very much for your comments and suggestions. We checked and revised the manuscript following your comments and suggestions as following. We hope that the revised manuscript overcomes the defects. Thank you again for your valuable comments and suggestions.
Comment 1: “The references need to be formatted, it is starting from “[2], and reference [1] is missing.”
Response 1: Thank you for your comment. We checked and revised the references.
Comment 2: The author should provide a detailed rebuttal report.
Response 2: Thank you for your suggestions. We responded in detailed for each of your comment. We hope that the revised manuscript based on your comments and suggestion and our response in this time are improved compared to the previous version. Thank you very much for your valuable comments and suggestions.
Comment 3: “The introduction is very short and poor in the literature review. The author needs to elaborate the introduction section. The author may add the following latest pieces of literature to make the literature richer i.e.,
https://0-doi-org.brum.beds.ac.uk/10.1016/j.seta.2022.102677 , https://0-doi-org.brum.beds.ac.uk/10.1016/j.rser.2022.112916, (in Lines 28-30), and https://0-doi-org.brum.beds.ac.uk/10.1016/B978-0-12-823007-7.00015-8, (in Lines 31-43).”
Response 3: Thank you for your comments and suggestions. We added various references including your suggested literature and discussed many aspects relating to topic of our manuscript such as impact of CO2 emission, methods to reduce CO2 emission, some focuses on the system for CO2 reduction presented in the manuscript. Your suggestions are very valuable for my revision.
Comment 4: “The novelty and significance of the study need to be clearly stated in the last paragraph of the introduction.
Lines 98-103 state that recent studies have been investigated, however, in the review the studies focussed are outdated i.e., more than a decade old (i.e., from 2007, 2010, 2012, 1985, 2009, 2011). Hence the essence of the state-of-the-art review is missing. The older literature needs to be removed and the latest investigations need to be added.”
Response 4: Thank you for your valuable comments and suggestions. We revised the introduction section and presented novelty and the significance of the study. We hope that the revised version overcomes the defects. Additionally, we checked our manuscripts and removed many references published before 2013 as your suggestions. Furthermore, we added a lot of references published mainly in the last 5 years and updated our manuscript based on the added references. We keep less than references which are basic knowledge and critical to topic of our manuscript published before 2013. The reference published from 2013 accounts for more than 80% of total references. We hope that the revised version overcomes the defects.
Comment 5: “The different sections discussed do not have a flow and connection. The different sections need to be connected. The sentence doesn’t make any sense. The author must check the statement.”
Response 5: Thank you for your comments. We revised each section and discussed the relationship between the sections. We hope that the revised version overcomes the defects.
Comment 6: The introduction and almost every section of the manuscript look dull to the readers. The author must add some pictorial representations/figures in the manuscript to make it more presentable and interesting to the readers.
Response 6: Thank you for your comments. We inserted figure 1 (Schematic of two representative systems in electrochemical reduction of CO2 to produce value-added chemicals catalyzed by whole-cell biocatalysts) in introduction section and figure 2 (Strategies for enhancement of the electrochemical reduction of CO2 to produce value-added chemicals). We hope that the revised version overcomes the defects.
Comment 7: “The manuscript is poor in the literature review. A lot more literature needs to be added in the different sections apart from the above-suggested pieces (like a total of 100 references for a review manuscript), to match the standards of Processes MDPI.”
Response 7: Thank you for your valuable comments and suggestions. We added many references mainly published in the last 5 years and total reference in the revised manuscript is more than 100. Additionally, we updated our manuscript in each section based on added references. We hope that the revised version improved compared to the previous one.
Comment 8: “The author needs to discuss the different discussions, and not only report the literature. Further, the author should include a concluding statement in each subsection.”
Response 8: Thank you for your comments. We updated many latest references and discussed various aspects of topics in our revised manuscript. Additionally, we included statement on each subsection. We hope that the revised version improved compared to the previous one.
Comment 9: “The manuscript needs to be proofread for better clarity and to eliminate grammatical errors from a professional/native proofreading service”
Response 9: Thank you for your comments. We proofread entire the manuscript, rewrote many parts, and eliminated grammatical errors. We hope that the revised version overcomes the defects.
Author Response File: Author Response.pdf
Reviewer 2 Report
The authors have taken into account all the suggestions made. The appropriate changes have been made in the revised manuscript. Therefore, I recommend this manuscript for publication.
Author Response
Thank you very much for your valuable comments and suggestions.
Reviewer 3 Report
The article has been improved in the state of the art and style details, so I consider it can be published
Author Response
Thank you very much for your valuable comments and suggestions.
