Emerging Sustainability in Carbon Capture and Use Strategies for V4 Countries via Biochemical Pathways: A Review

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The introduction section gives a very good introduction about the importance of this paper, it also explains the goals and the novelty of the review. On the other hand, the rest of the paper summaries the most important issues to take into account in the evaluation of a sustainable process using microalgae and the possibilities of the future of these technologies and the research. They compare the reported findings with the literature, highlighting and discussing the most important matters. In addition, figures and tables give added value to the review, pointing out the main conclusions. Maybe the conclusion section can be shortened. Finally, the references are appropriate.

I have only the following comments:

-        -  Please, add a sentence about the conclusions of the importance of the LCA in the abstract section.

-         - Please, try to summarize the conclusion section, highlighting the most important ones. Maybe you can add more information in the discussion section if you wish. 

Author Response

Dear Reviewer. I appreciate your positive comments and given suggestions. The crucial LCA statements were added to the abstract. Regarding the conclusion, it was reduced to pointing out the main facts and message to readers. Some information was transferred from the conclusion to the discussion section. Grammarly PRO, DeepL and MyPlag also checked the manuscript regarding grammar and stylistics.

Reviewer 2 Report

Comments and Suggestions for Authors

Line 49, “the” global effort should be “a” global effort

I would suggest to replace “methane fermentation” to “anaerobic digestion”

In line 274, please add 2-3 studies reported pre-treatment methods and different operating temperatures to encounter the low C/N issues and rapid ammonia increase in the anaerobic digestion.

In line 286; please include more examples for CO2 removal from the biogas in addition to the membrane, and also add references for these examples.

In line 287; please discuss 1-2 studies for CO2 removal efficiency using microalgae

In line 302, process word is repeated; An increase in “process” temperature of the “process”

Please include co-digestion of microalgae with food waste; for instance;

Sun, C., Xia, A., Liao, Q., Fu, Q., Huang, Y., & Zhu, X. (2019). Life-cycle assessment of biohythane production via two-stage anaerobic fermentation from microalgae and food waste. Renewable and Sustainable Energy Reviews, 112, 395-410.

Ferreira, L. O., Astals, S., & Passos, F. (2022). Anaerobic co‐digestion of food waste and microalgae in an integrated treatment plant. Journal of Chemical Technology & Biotechnology, 97(6), 1545-1554.

In table 1, the technology column needs to be aligned similar to table 2.

In line 498; please add SWOT acronym for Strengths, Weaknesses, Opportunities and Threats.

In the abstract, the authors mentioned “Process characteristics”, please include more information about the process characteristics in the review where it is applicable.

Author Response

Dear Reviewer. I appreciate your positive comments and given suggestions. The manuscript was improved according to your suggestion discussed below. Grammarly PRO, DeepL and MyPlag also checked the manuscript regarding grammar and stylistics.

 

“Line 49, “the” global effort should be “a” global effort.”

Accepted, modified.

 

“I would suggest to replace “methane fermentation” to “anaerobic digestion””.

Accepted, modified.

 

“In line 274, please add 2-3 studies reported pre-treatment methods and different operating temperatures to encounter the low C/N issues and rapid ammonia increase in the anaerobic digestion.”

Added to the manuscript.

 

“In line 286; please include more examples for CO2 removal from the biogas in addition to the membrane, and also add references for these examples.”

Added to the manuscript.

 

“In line 287; please discuss 1-2 studies for CO2 removal efficiency using microalgae”.

Added to the manuscript.

 

“In line 302, process word is repeated; An increase in “process” temperature of the “process””.

Corrected.

 

“Please include co-digestion of microalgae with food waste; for instance”.

• Sun, C., Xia, A., Liao, Q., Fu, Q., Huang, Y., & Zhu, X. (2019). Life-cycle assessment of biohythane production via two-stage anaerobic fermentation from microalgae and food waste. Renewable and Sustainable Energy Reviews, 112, 395-410.
• Ferreira, L. O., Astals, S., & Passos, F. (2022). Anaerobic co‐digestion of food waste and microalgae in an integrated treatment plant. Journal of Chemical Technology & Biotechnology, 97(6), 1545-1554.”

The co-digestion of microalgae with food waste and the LCA study were referenced in the manuscript under the fermentation and LCA sections.

 

“In table 1, the technology column needs to be aligned similar to table 2.”

The sustainability template allows using the given format in Table 1-2. Thus, its graphical artwork was not changed due to a better visual interpretation of the presented information.

 

“In line 498; please add SWOT acronym for Strengths, Weaknesses, Opportunities and Threats.”

Added to the manuscript.

“In the abstract, the authors mentioned “Process characteristics”, please include more information about the process characteristics in the review where it is applicable.”

The abstract was rewritten to be more exact and to avoid any unclarities.

Reviewer 3 Report

Comments and Suggestions for Authors

1) Abstract needs to be rewritten. As it currently stands, it reads as a paragraph just listing key terms.

2) Lines 72-110 read a one long list of different studies. This needs to be written in a more conversational format.

3) Is Figure 5 taken by the authors or have photos been approved for reprint?

4) Please explain in line 196, what the term "lipids" is referring too.

 

 

Comments on the Quality of English Language

This is a very good review with extensive background knowledge and detail of carbon capture strategies. However, the grammar needs to be severely edited. Please fix all run-on sentences, and have this properly checked for  grammatic errors.

Author Response

“Comments on the Quality of English Language

This is a very good review with extensive background knowledge and detail of carbon capture strategies. However, the grammar needs to be severely edited. Please fix all run-on sentences, and have this properly checked for  grammatic errors.”

 

Dear Reviewer. I appreciate your positive comments and given suggestions. The manuscript was improved according to your suggestion discussed below. Grammarly PRO, DeepL and MyPlag also checked the manuscript regarding grammar and stylistics.

 

“1) Abstract needs to be rewritten. As it currently stands, it reads as a paragraph just listing key terms.”

The abstract was rewritten to be more exact and to avoid any unclarities.

 

“2) Lines 72-110 read a one long list of different studies. This needs to be written in a more conversational format.”

Hopefully, the presented information was rewritten into a more conversational format.

 

“3) Is Figure 5 taken by the authors or have photos been approved for reprint?”

All the figures are covered by copyrights that allow their publication. The editor has it already available.

 

“4) Please explain in line 196, what the term "lipids" is referring too.”

The explanation was precise in the manuscript.

Reviewer 4 Report

Comments and Suggestions for Authors

This paper, entitled Emerging Sustainability in Carbon Capture and Use Strategies for V4 Countries via Biochemical Pathways: A Review., is a scholarly work and can increase knowledge on this domain. The authors provide an interesting and original study, the content is relevant to Sustainability.

I have some general and specific comments:

- abstract and keywords are meaningful

- the manuscript is quite well written and well related to existing literature.

- please consider also use of nutrients from digestate for microalgae cultivation from anaerobic digestion / digestate

- what are the main limits and advantages of such approach?

- What about transfer and applicability at real scale? What about industrialization of such approach?

- please discuss about energy balances of all approaches developed in this paper

As it this paper is not fully acceptable for publication and requires some amendments and additional information. I recommend the following decision: ACCEPT AFTER MINOR REVISION.

Author Response

“This paper, entitled Emerging Sustainability in Carbon Capture and Use Strategies for V4 Countries via Biochemical Pathways: A Review., is a scholarly work and can increase knowledge on this domain. The authors provide an interesting and original study, the content is relevant to Sustainability.”

I have some general and specific comments:

- abstract and keywords are meaningful

- the manuscript is quite well written and well related to existing literature.

As it this paper is not fully acceptable for publication and requires some amendments and additional information. I recommend the following decision: ACCEPT AFTER MINOR REVISION.”

 

Dear Reviewer. I appreciate your positive comments and given suggestions. The manuscript was improved according to your suggestion discussed below. Grammarly PRO, DeepL and MyPlag also checked the manuscript regarding grammar and stylistics.

 

“- please consider also use of nutrients from digestate for microalgae cultivation from anaerobic digestion / digestate”

- what are the main limits and advantages of such approach?

- What about transfer and applicability at real scale? What about industrialization of such approach?”

Added to the chapter 2.2.1.

 

“- please discuss about energy balances of all approaches developed in this paper”

This is a great idea. Available techno-economic studies with mass and energy balances are based on the different process setups. This leads to additional energy flow, CAPEX, and OPEX. An original techno-economic study must be done for fixed input parameters and different processing pathways. However, this is the topic for a new paper, not for such a manuscript. The review aimed to show the sustainable biochemical CO2 transformation pathways in the microalgal biorefinery concept.

Reviewer 5 Report

Comments and Suggestions for Authors

Highlight changes in yellow in a next revision, please. No track changes.

 

Dear authors, I would suggest the abstract to start with a brief contextualization.

The methodology on the critical review needs to be clarified.

It would be important to highlight the novelty of this review, compared to other, so the relevance involved needs to be highlighted, its practical implications.

 

Please make sure to remove all non original date, particularly if non modified.

“Figure 1. Annual CO2 emissions by V4 countries in 2000, 2010, 2022 [2].”

The same in all other cases.

 

Authors need to replace published material by own schemes.

 

The methodology needs to be clarified through the entire text.

 

Then, in such cases, the sources used to build this scheme, even if original, need to be mentioned...

“Figure 7. The idea of technology for the production of thermostable C-PC – circular approach.”

 

This is a review, the authors mention it, so the approach behind the critical review need to be clarified and the information presented in the table needs to be supported in a column of references (authors, names):

“Table 1. Sustainability of reviewed CO2-to-X conversion pathways.”

The same in all similar cases

 

There is some similarity that needs to e addressed, sentences spread through the manuscript, but were references are not mostly present.

 

There is similarity here, no references are presented:

“Table 3. SWOT analysis for demonstrated technological pathways.”

 

These are conclusions, full of similarity, not possible in the conclusions

“as biofuels and feed still suffer from low profitability and negative energy balance. Third- generation biomass is a promising alternative for bioethanol production through pretreat- ment, enzymatic hydrolysis, digestion, and distillation. These procedures are imple- mented at large scales in a thriving economic and eco-friendly way. However, there are still some disadvantages (high-cost harvesting biomass) and potential threats holding back the development of industrial bioethanol; therefore, the overall techno-economic analysis of the process is critical. This sustainability of microalgae biorefineries requires to be evaluated by a life cycle assessment study. LCA compares the life cycle process, cradle-to-grave, environmental impact, transport, distribution, and marketing commer- cial production. The implementation of algae biorefinery has the potential to generate a sustainable portfolio of products, including biofuels. More study is necessary, though, to determine whether it is feasible to produce various items economically. Various processes can be coupled to cut down on operation costs. To build a successful algal biorefinery, efficient biomass generation is required. Environmental factors such as the use of CO2 and wastewater should be considered for a successful biorefinery. Continuous biomass gen- eration and conversion to high-value products using effective separation methods and low power usage can lead to a successful algal biorefinery operation in the near future.”

 

A Conclusions sections needs to start by brief contextualization and methodology, main findings and practical implications, limitations and future prospects.

 

The relevance of this review needs to be highlighted. I hope the authors are able to understand the above comments because a review needs to go beyond what exists.

 

Again, let me leave it very clear, the authors need to justify the approach used, based on references too, and explain all criteria.

Comments on the Quality of English Language

moderate

Author Response

Dear Reviewer. I appreciate your positive comments and given suggestions. The manuscript was improved according to your suggestion discussed below. Grammarly PRO, DeepL and MyPlag also checked the manuscript regarding grammar and stylistics.

 

"Dear authors, I would suggest the abstract to start with a brief contextualization."

The abstract was rewritten to be more exact and to avoid any unclarities.

 

"The methodology on the critical review needs to be clarified. It would be important to highlight the novelty of this review, compared to other, so the relevance involved needs to be highlighted, its practical implications."

The information about keyword searches in the database and data mining were added. The novelty of the paper is highlighted.

 

 "Please make sure to remove all non original date, particularly if non modified. Figure 1. Annual CO2 emissions by V4 countries in 2000, 2010, 2022 [2]. The same in all other cases."

The information about the dates in the figure captions was deleted for Figures 1-3 .

 

"Authors need to replace published material by own schemes. Then, in such cases, the sources used to build this scheme, even if original, need to be mentioned... This is a review, the authors mention it, so the approach behind the critical review needs to be clarified and the information presented in the table needs to be supported in a column of references (authors, names)”

The authors are against this demand. Authors provide their artwork in the manuscript or have copyright permission to publish given schemes. No reference means that the artwork is one's own.

• Figures 1-3 – own graphs were created on the referenced databank.
• Figures 4-5 – copyright permission to publish it (Editor has it available).
• Figures 6-7 – own photos and figures.
• Tables 1-4 – own definitions.

 

“There is some similarity that needs to e addressed, sentences spread through the manuscript, but were references are not mostly present.

• Table 3. SWOT analysis for demonstrated technological pathways.
• These are conclusions, full of similarity, not possible in the conclusions”

Yes, the reviewer is correct about the similarities because the conventional terms are used. Some sentences were rewritten to avoid possible suspicion of plagiarism. The sentences are coming from my papers. They were changed in the sentence style without changing the original meaning.

 

“A Conclusions sections needs to start by brief contextualization and methodology, main findings and practical implications, limitations and future prospects.”

Regarding the conclusion, it was reduced to pointing out the main facts and message to readers. Some information was transferred from the conclusion to the discussion section.

 

 

“The relevance of this review needs to be highlighted. I hope the authors are able to understand the above comments because a review needs to go beyond what exists. Again, let me leave it very clear: the authors need to justify the approach used, based on references, and explain all criteria.”

The new paragraphs and formulations that should cover all these tasks were added to the manuscript.

Round 2

Reviewer 5 Report

Comments and Suggestions for Authors

Highlight changes in yellow in a next revision, please. No track changes.

 

Dear authors, clearly, even considering the answers given,  the manuscript needs to have all changes indicated in different colour. It is obviously easier for the reviewer, who spends precious time comparing.

 

This is not a contextualization, just to find the need to publish this paper. This is immediately the objectives of the article...

Please go back to my previous comments.

“Abstract: The paper serves the current scientific knowledge for CO2 transformation via biochemical pathway to microalgal biomass with its subsequent treatment to biofuels and bioproducts assuming milder climatic conditions (central or eastern Europe, Visegrad countries or climatically related world regions).”

 

Expressions such as below should be clearly avoided because they are not assertive.

“Nevertheless, m”

 

When mentioning the term review in an article, and particularly in a title, then the methodology needs to be clearly explained. It is not the case here.

“The sustainability of presented microalgal biorefinery pathways was evaluated by reviewing available life cycle assessment studies.”

 

I do not really find an answer to this in the new abstract

“"The methodology on the critical review needs to be clarified. It would be important to highlight the novelty of this review, compared to other, so the relevance involved needs to be highlighted, its practical implications."

The information about keyword searches in the database and data mining were added. The novelty of the paper is highlighted.”

 

I am sorry to say that again. The caption is not clear. Is this original data or not? If not, make sure to clearly add if adapted, modified, and add the author’s names first and then reference.

“Figure 1. Annual CO2 emissions by V4 countries [2].”

 

So once again, I did not understand the answer.

“"Please make sure to remove all non original date, particularly if non modified. Figure 1. Annual CO2 emissions by V4 countries in 2000, 2010, 2022 [2]. The same in all other cases."

The information about the dates in the figure captions was deleted for Figures 1-3 .”

 

Well, I’m sorry to say that I do not agree with the authors. If the authors base their own work in others, publications, then that reference needs to be included at the end of the caption. But it needs to be clarified if adapted, modified based on using data from etc.

“"Authors need to replace published material by own schemes. Then, in such cases, the sources used to build this scheme, even if original, need to be mentioned... This is a review, the authors mention it, so the approach behind the critical review needs to be clarified and the information presented in the table needs to be supported in a column of references (authors, names)”

The authors are against this demand. Authors provide their artwork in the manuscript or have copyright permission to publish given schemes. No reference means that the artwork is one's own.

• Figures 1-3 – own graphs were created on the referenced databank.
• Figures 4-5 – copyright permission to publish it (Editor has it available).
• Figures 6-7 – own photos and figures.
• Tables 1-4 – own definitions.”

Please see that many journals presently demand specifically to be indicated at the end of the caption if it was the author’s own work or not, precisely to avoid all such issues.

 

I am sorry it has nothing to do with conventional terms. It has to do with the entire sentences were part of the sentences that should be rewritten.

““There is some similarity that needs to e addressed, sentences spread through the manuscript, but were references are not mostly present.

• Table 3. SWOT analysis for demonstrated technological pathways.
• These are conclusions, full of similarity, not possible in the conclusions”

Yes, the reviewer is correct about the similarities because the conventional terms are used.”

 

It doesn’t matter where do sentences come from. It is plagiarism anyway. I tis self plagiarism. In this case, I am sure the authors are perfectly aware of that.

I insist that in several cases, the references are not even present.

“Some sentences were rewritten to avoid possible suspicion of plagiarism. The sentences are coming from my papers. They were changed in the sentence style without changing the original meaning.”

 

Because this is a review, and because of the contente being presented, authors need to presente the references where i tis information was based on, clearly. So, please add a column with such references

“Table 2. Sustainability of reviewed CO2-to-X conversion pathways.”

 

the same here.

“Table 4. SWOT analysis for demonstrated technological pathways.”

 

Significant similarity here…

“The implementation of algae biorefinery has the potential to generate a sustainable portfolio of products, including biofuels. There are still research needs and challenges in Table 3, followed by SWOT analysis (Strengths, Weaknesses, Opportunities and Threats) in Table 4, limiting their realization on an industrial scale. More study is necessary, though, to determine whether it is feasible to produce various items economically. Vari- ous processes can be coupled to cut down on operation costs. To build a successful algal biorefinery, efficient biomass generation is required. Environmental factors such as the use of CO2 and wastewater should be considered for a successful biorefinery. Continuous biomass generation and conversion to high-value products using effective separation methods and low power usage can lead to a successful algal biorefinery operation in the near future. Moreover, machine learning methods are needed for data mining, process control, process optimization and geometrical configuration of reactors and bioreactors.”

 

The conclusions section needs to start with a brief contextualization of why is this study being presented? Then brief methodology, then main findings, practical implications, limitations and future prospects. Please highlight the novelty of this review compared to others. See dot the last parto f the conclusions has similarity. I’m sorry this is not possible. This is a new study. These are new conclusions.

 

Again, let me leave it very clear in relation to the methodological approach being used, the authors need to justify the approach used, based on references too, and explain all criteria.

Comments on the Quality of English Language

Moderate

Author Response

Dear Reviewer. We appreciate your positive comments and given suggestions. The author team followed your recommendations and clarified all the missing information.

 

"Dear authors, clearly, even considering the answers given,  the manuscript needs to have all changes indicated in different colour. It is obviously easier for the reviewer, who spends precious time comparing. "

-> Honestly, the submission system does not allow submitting the manuscript directly with highlighted changes as commonly available by Elsevier or Springer Editorial Systems. The author team respected the reviewer's request. All the changes are tracked by the yellow colour as submitted as supplementary material.

 

"Expressions such as below should be clearly avoided because they are not assertive.

Nevertheless, m…"

-> The words "nevertheless, however, thus or therefore" were deleted per your recommendation.

 

"When mentioning the term review in an article, particularly in a title, the methodology needs to be clearly explained. It is not the case here. I do not really find an answer to this in the new abstract. The information about keyword searches in the database and data mining were added. The novelty of the paper is highlighted."

-> A deeper explanation of methodology was added to the manuscript. The abstract got a better explanation of the term "review".

 

"I am sorry to say that again. The caption is not clear. Is this original data or not? If not, make sure to clearly add if adapted, modified, and add the author's names first and then reference. "Figure 1. Annual CO2 emissions by V4 countries [2]. The information about the dates in the figure captions was deleted for Figures 1-3 ."

"Well, I'm sorry to say that I do not agree with the authors. If the authors base their own work in others, publications, then that reference needs to be included at the end of the caption. But it needs to be clarified if adapted, modified based on using data from etc."

-> The author team fully respect the referencing style. The data from the database and the numeric values were taken from the reference given and originally plotted by the authors into the presented graph. The name of the website source enriched the figure captions for Figures 1-3. No reference means that the artwork is one's own. We add the sentence "Source: own elaboration "to clarify it.

 

It doesn’t matter where do sentences come from. It is plagiarism anyway. I tis self plagiarism. In this case, I am sure the authors are perfectly aware of that. I insist that in several cases, the references are not even present. Because this is a review, and because of the contente being presented, authors need to presente the references where i tis information was based on, clearly. So, please add a column with such references “Table 2. Sustainability of reviewed CO2-to-X conversion pathways.” the same here. “Table 4. SWOT analysis for demonstrated technological pathways.”

-> Both the Table 2 and Table 3 are our own engineering contribution to the field. We add the sentence "Source: own elaboration "to clarify it.

Significant similarity here…in the paragraph: “The implementation of algae biorefinery has the potential to generate a sustainable portfolio of products, including biofuels. There are still research needs and challenges….”

-> Honestly to the Reviewer, our available software, Grammarly PRO and MyPlag, detected zero per cent of plagiarism in this paragraph and full manuscript.

 

The conclusions section needs to start with a brief contextualization of why is this study being presented? Then brief methodology, then main findings, practical implications, limitations and future prospects. Please highlight the novelty of this review compared to others. See dot the last parto f the conclusions has similarity. I’m sorry this is not possible. This is a new study. These are new conclusions.

-> The conclusion was entirely rewritten with the respect of not being identical to the abstract.

Author Response File: Author Response.pdf

Round 3

Reviewer 5 Report

Comments and Suggestions for Authors

Highlight changes in yellow in a next revision, please. No track changes.

 

MDPI does allow authors to submit without track changes and all changes in yellow.

I have done it and asked it often.

Try to review a tracked changed document...

 

It seems authors do not understand or are not willing to do the requested revisions.

I was clear every time, as detailed, contrary to the authors.

It is my perspective that the authors need to go back and attend every points raised. not the case.

 

In the case od used data, it needs to be clear to be taken from, adapted, modified..

In the case of grouped figures, there needs to be  subcaption by letter in every case.

Figure 3 is just an example

 

In the case of the beginning of the abstract, the contextualization is not clear

In the case of methodology (to be present in abstract methods and conclusions...), it needs to be further worked, because authors use the term “review” in the title...

including inclusion and exclusion criteria.

Much information is lacking

 

In the case of tables, as table 2, information was based on reading, so the reference base needs to be there, in all cases, Figure 7 is another example, unless this is all NEW information, which is not the case...

 

In the case of similarity, it needs to be revised.

This is just an example:

“The implementation of algae biorefinery has the potential to generate a sustainable portfolio of products, including biofuels. There are still research needs and challenges in Table 3, followed by SWOT analysis (Strengths, Weaknesses, Opportunities and Threats) in Table 4, limiting their realization on an industrial scale. More study is necessary, though, to decide whether it is feasible to produce various items economically. Various processes can be coupled to cut down on operation costs. To build a successful algal bio- refinery, efficient biomass generation is required. Environmental factors such as the utili- zation of CO2 and wastewater should be considered for a successful biorefinery. Contin- uous biomass generation and conversion to high-value products using effective separa- tion methods and low power usage can lead to a successful algal biorefinery operation in the near future. Moreover, machine learning methods are needed for data mining, process control, process optimization and geometrical configuration of reactors and bioreactors.”

 

The conclusions section needs to be much more extensive, comparing this “review” with others, in terms of novelty. What is the added value, compared to? and indicate which reviews...

Comments on the Quality of English Language

Moderate

Author Response

"MDPI does allow authors to submit without track changes and all changes in yellow. I have done it and asked it often. Try to review a tracked changed document..."

-> Two documents were submitted after the second revision – highlighting yellow changes and after the corrections. The tracked document with yellow changes was submitted directly to You as a file for Reviewer 5. Regarding Round 3, only one document is submitted. The main manuscript includes all the changes highlighted in yellow.

 

"It seems authors do not understand or are not willing to do the requested revisions. I was clear every time, as detailed, contrary to the authors. It is my perspective that the authors need to go back and attend every points raised. not the case."

-> Authors always tend to improve the paper quality according to all the reviewers' comments. Great emphasis has also been placed on dealing with the comments of Reviewer 5 in all the rounds. Our comments about the given task were always clearly pointed out, and the manuscript has visible changes. Sometimes, it is hard to understand the comment's exact meaning, which leads to misunderstandings.  

 

"In the case od used data, it needs to be clear to be taken from, adapted, modified.

-> Figures 1-4 have defined sources from which they were adapted.

 

"In the case of grouped figures, there needs to be subcaption by letter in every case. Figure 3 is just an example."

-> Figure 3 represents the group figure. The reference [5] presents the annual CO2 emissions by sectors and countries worldwide, i.e., the data database is one source. The authors only subtracted data and delivered targeted countries in graphical artwork. There is no need to reference the subcaption.

-> Figure 5 represents the group figure. It is published in this format in the reference [36]. Check reference [36]. There is no need to reference the subcaption.

 

"In the case of the beginning of the abstract, the contextualization is not clear."

-> The sentences about contextualization were added to the abstract.

 

"In the case of methodology (to be present in abstract methods and conclusions...), it needs to be further worked, because authors use the term "review" in the title...including inclusion and exclusion criteria. Much information is lacking."

-> The new chapter "Methodology" was added to the manuscript. It includes information about keywords, data searching, inclusion and exclusion criteria, and review forming.

 

"In the case of tables, as table 2, information was based on reading, so the reference base needs to be there, in all cases."

-> OK, we respect this comment. The reference base was added to Table 2-4.

 

"Figure 7 is another example, unless this is all NEW information, which is not the case..."

-> References were added.

"In the case of similarity, it needs to be revised. This is just an example: "The implementation of algae biorefinery has the potential to generate a sustainable portfolio of…".

-> Honestly to the Reviewer, our available software, Grammarly PRO and MyPlag, still detect zero per cent of plagiarism in this paragraph and in the body of the manuscript. The highlighted paragraph was rewritten.

 

"The conclusions section needs to be much more extensive, comparing this "review" with others, in terms of novelty. What is the added value, compared to? and indicate which reviews..."

-> The paper had a much more extensive conclusion at the beginning. Regarding round 1, Reviewer 1 demanded to shorten the conclusion to pointing out the main facts and message to readers. Information about conceptualization, novelty and deeper information was transferred from the conclusion to the discussion section. The authors are between two different recommendations now. But the Authors respect your demand and added some contextualization, novelty, its added value to the conclusion.