Optimization of Liquid Hot Water Pretreatment and Fermentation for Ethanol Production from Sugarcane Bagasse Using Saccharomyces cerevisiae

Round 1

Reviewer 1 Report

Review catalysts-1670306

Presented manuscript entitled Optimization of liquid hot water pretreatment and fermentation for ethanol production from sugarcane bagasse using Saccharomyces cerevisiae concerns use of sugarcane bagasse in production of ethanol. Manuscript is well prepared, and the proposed study might be technically sound for a broad variety of readers. However, I have some comment to improve the quality of work.

Introduction section. In my opinion the matter of bioethanol is very interesting. Please add more information about production of bioethanol and other biofuels nowadays.

Please more emphasize why you decided to use sugarcane bagasse as a source for bioethanol production. Why not other source of biomass?

Based on chemical composition of sugarcane bagasse, please discuss the advantage of this substrate with comparison to others.

Conclusion. In my opinion this work is good, however there is lack of better emphasizing of the obtained results. The Conclusion section must be expanded.

There is a lot of editorial issues and typo mistakes.

Comments for author File: Comments.pdf

Author Response

We have the pleasure of sending You the manuscript entitled “Optimization of Liquid Hot Water Pretreatment and Fermentation for Ethanol Production from Sugarcane Bagasse Using Saccharomyces cerevisiae” to be considered for publication as a research article in your prestigious journal. Our work is containing original research and has not been published earlier in any journal and is not being considered for publication elsewhere. All authors have seen and approved the manuscript and have contributed significantly for the paper.   

 

We hope that our work are enriching the quality of the article, it could be accepted for publication in Catalysts.

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

The paper is very interesting, well written and well organized. The ways and means are well described as well as the obtained results which are statistically analyzed. However, in order to make it a stronger paper, I suggest some points before it be published:

• Introduction needs improvement. It should make clear the novelty of the work. Why to chose LHW pretreatment? Authors mention optimization of organosolv and alkaline pretreatment, which is a little out of subject in the introduction. What about works studying LHW of sugarcane bagasse? What is the lack of knowledge that this work is contributing? I believe the inclusion of the works below as references will improve substantially the manuscript.

- Zhang et al. Co-production bioethanol and xylooligosaccharides from sugarcane bagasse via autohydrolysis pretreatment. Renewable Energy, https://doi.org/10.1016/j.renene.2020.10.034.

- Milessi et al. Xylooligosaccharides production chain in sugarcane biorefineries: From the selection of pretreatment conditions to the evaluation of nutritional properties. Industrial Crops and Products, https://doi.org/10.1016/j.indcrop.2021.114056

- Silva et al. Ethanol production from sugarcane bagasse using ssf process and thermotolerant yeast. doi: 10.13031/trans.58.11024

• Line 48: the sugarcane bagasse is not completely considered as waste anymore, once it is used to energy cogeneration. It is a valuable byproduct from sugarcane processing that can be used as a rich carbon source too. Please rephrase the sentence.

Results:

• Item 2.1 says that the composition of the pretreatment sugarcane bagasse is given, however what is presented in this item is the native sugarcane bagasse. Please correct item title.
• Please improve figure 1 caption, it should be self-explanatory
• What are the pretreatments from Table 1 severity factor? This is a very important information to correlate with glucose yield.
• Line 186: “Thus, cerevisiae has high potential for fermenting sugars into ethanol.”, this is a very old information, and can be removed from the manuscript.
• Item 2.5 should comprehend the comparison with other reports from literature of SSF of LHW pretreated sugarcane bagasse. Please improve it.
• Figure 3: please add deviation bars.
• In methodology authors says that HMF and furfural were quantified, where are these results?

Methodology:

• In the text it is not clear why the pretreatment used is considered a LWH pretreatment if it used acid. Why it is not diluted acid pretreatment?
• Please add a table with experimental design conditions specifications (codded variables, -1/0/1)
• Line 252: Erlenmeyer flasks of 1mL? is it correct?
• Equation 4 number is dislocated into the text (line 277)
• Please provide references for the SSF conditions used

Author Response

We have the pleasure of sending You the manuscript entitled “Optimization of Liquid Hot Water Pretreatment and Fermentation for Ethanol Production from Sugarcane Bagasse Using Saccharomyces cerevisiae” to be considered for publication as a research article in your prestigious journal. Our work is containing original research and has not been published earlier in any journal and is not being considered for publication elsewhere. All authors have seen and approved the manuscript and have contributed significantly for the paper.   

 

We hope that our work are enriching the quality of the article, it could be accepted for publication in Catalysts.

Please see the attachment.

Author Response File: Author Response.pdf