Impact of Lentinus sajor-caju on Lignocellulosic Biomass, In Vitro Rumen Digestibility and Antioxidant Properties of Astragalus membranaceus var. mongholicus Stems under Solid-State Fermentation Conditions
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe research presented in the article entitled Impact of Lentinus sajor-caju on Lignocellulosic Biomass, In Vitro Rumen Digestibility and Antioxidant Properties of Astragalus membranaceus var. mongholicus Stems Under Solid-state Fermentation Conditions presents interesting results that show the advantages of using bioprocesses for the transformation of materials and the improvement of their nutritional quality. Regarding the document, it is suggested: to include in Tables 1, 2 and 3 the error associated with each of the measurements; to change the colors of Figure 3 for better visualization.
Author Response
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Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis work presents the bioconversion of lignocellulosic biomass af by Lentinus sajor-caju. The conversion altered the composition of the cell wall of AMM stems and enhanced its antioxidant activity. The antioxidant activity was correlated with the total phenolic content.
The authors should highlight how their work contributes to the existing literature. They should point out the importance of their work and findings.
The authors should carefully check the manuscript for typos.
The authors should add correlation of their findings and literature where feasible.
Line 47, ‘It has been long been known that’ should be changed to ‘It has long been known that’.
Regarding the findings presented in lines 304-353 are there previous works for corellation? If so, please provide the literature.
Lines 333-335 the authors report ‘In our study, the ligninolysis contents were significantly decreased, 333 suggesting that white rot fungi L. sajor-caju fermentation could facilitate the conversion of 334 polyphenol compounds, thereby enhancing the biological………. of AMM stems’. Something is missing from this sentence.
Lines 351-353 ’The results of correlation 351 showed that although the down-regulated metabolite FC changed greatly, it had little 352 correlation with antioxidant.’ should be changed to ‘The results of correlation 351 showed that although the down-regulated metabolite FC changed greatly, it had little 352 correlation with antioxidant activity.’
Lines 357-358 ‘Correlation analysis indicated that relationship between different metabolites and 357 antioxidant properties.’ should be changed to ‘Correlation analysis indicated the relationship between different metabolites and 357 antioxidant properties. ‘
Author Response
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Reviewer 3 Report
Comments and Suggestions for AuthorsPlease explain why the fermentation lasted 30 days.
Introduction
The review lacks an explanation of the differences between individual lignocellulases and the characteristics of their susceptibility to degradation. There is also no explanation of the role of cellulose, hemicellulose and lignin in the feed. The review should show which of these compounds constitute the greatest ballast in the feed and what transformations should be expected to increase the digestibility of the feed. It is worth trying to explain why the cellulose was so poorly degraded.
Methodology
The water content in CK and LC should be provided. For the in vitro digestibility test, 500 (50?) g samples were taken. 50 mL of buffered were added. If the water content in CK and LC were different, the proportions between DM and rumen fluid were also different. How could this have affected the obtained results? Please try to explain
Why did the in vitro fermentation last as long as 48 hours? How can this be related to in vivo conditions, i.e. the real time the feed stays in the rumen?
Results
If such a thorough analysis of metabolites (Figure 2) has been carried out, it is necessary to assess whether, for animal nutrition, changes in the amount of these metabolites (up or down) are beneficial or unfavorable?
A very extensive analysis of the metabolite content has been carried out. What real benefits result from these analyses? This analysis concerns only a specific, initial stage of digestion in the digestive tract. Can we therefore draw conclusions about nutritional benefits for cattle based on it?
Conclusion
Please assess the application possibilities of the conducted research. In practice, fungi can be inoculated on AMM stems, on which natural microflora lives (without the sterilization process). How can this affect the course of fermentation and its effects? Considering the fact that fungi grow in aerobic conditions, for 30 days, in conditions of high humidity (65%), please assess whether other, parallel microbiological processes will not cause changes in the biomass that will prevent the use of such feed?.
Detailed comments:
Line 101: probably impossible for a 500 g sample to fit into a 100 mL flask
165-7 explanations for the table, not text
Author Response
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Reviewer 4 Report
Comments and Suggestions for AuthorsThis study is interesting, however some improvements are required prior publication
1. At lines 263-264 is mention: "The pie charts clearly showed the significant differential abundance between differential metabolites in fermented-AMM stems and unfermented AMM stems (Figure 2a)."
However, this Figure not mention anything about it.
It is necessary to include a Table or figure to highlight the differences between the metabolites categories contained in the fermented-AMM stems and unfermented AMM stems samples. Also please include an explanation on this comparison.
Same remark for Table 4
Conclusions must be improved
Author Response
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Round 2
Reviewer 4 Report
Comments and Suggestions for AuthorsAgree with revised manuscript
