Enzymatic Pretreatment Improved the In Vitro Ruminal Degradability of Oil Palm Fronds

Round 1

Reviewer 1 Report

Dear Authors, thank you for  your submission.

The present work is generally well written, the scientific question clearly presented and of interest to the reader. The material and methods are well described and presented and the results supported by the data. Therefore I will recommend this article to be accepted in the present form.

With my best regards.

Emmanuel

Author Response

The author would like to extend sincere gratitude for the reviewer's response

Reviewer 2 Report

The Manuscript by Azmi et al., reports a method for the production of an improved ruminal degradability of oil palm fronds (OPF). The method took advantage of a pretreatment of the OPF using enzymatic extracts obtained from filamentous fungi present in OPF. The relevance of the study resides in the fact that it could be useful for the development of cost-effective farm animal feed production from agricultural by-product.

The manuscript is technically and methodologically sound and its content could be relevant in terms of future biotechnological application. However, the following major concerns have to be considered prior its consideration for publication.

 

1) Check the standard errors in all illustrations reporting histograms; in each graph they seem identical for each bar.

2) In the paragraphs 4.2.1. – 4.2.2. no mention has been done regarding the concentration of compounds/substrates and the pH of the buffers used.

3) A deep rephrasing throughout the manuscript is required, as the text in several parts looks like a spoken rather than written English. In addition, a lot of text repetitions are present (“apart from this”, “enzyme extract extracted”, etc.) and they should be avoided.

Author Response

• The standard error bar was checked. The value was indeed correct.
• The methods were amended and the details requested were added.
• The comment was noted and appropriate corrections regarding the language used were made.

Reviewer 3 Report

Title: Enzymatic Pretreatment Improved the In Vitro Ruminal 2 Degradability of Oil Palm Fronds

The authors were investigated the in vitro ruminal degradability of oil palm fronds (OPF) through enzymatic pretreatment. The authors were designed the work systematic way with performing some valuable works. It is also necessary to critically evaluate new data and do not make hasty conclusions which may lead to misinterpretations. However, several points are important to be addressed before going to possible publication in this high-quality journal. Also, the authors need to address all points in the revision stage for broad range readers understanding.

 

-Abstract: The present Abstract is too short to understand. Please keep in mind that this section is completely different than the Introduction section. The main findings with important opinions are acceptable. The authors need to consider these points in the revision stage.

 

- Barring a few sentences in the text, the English language is fair. However, the text is not free

from grammar errors. Ensure that your English manuscript is guaranteed free of language issues. In addition, the manuscript should be thoroughly checked for English corrections as there are some colloquial terms being used.

 

-For the highlights, it is much better to state the main finding, the novelty and the intrinsic causes. Also, the author needs to add the highlight and graphical abstract in the revision stage.

 

 

-References: There are many references are not adjacent with this study. The authors need to take note in the revision stage and cite relevant references including high impact journal to make the manuscript in broad range readers. Also, the numbers of references need to be extended in the revision stage.

 

-Scientists were considered the any technology based on the sensitivity, cost effective and so on. The authors need to indicate such point in the revised manuscript.

-Conclusion also needs to be rewritten. Include the following: new concepts and innovations demonstrated in this study, summary of findings, comparison with findings by other workers, and concluding remark.

Author Response

• The abstract was amended. Important findings were added to the abstract. The length of the abstract is limited to 200 words as stated in the author's guideline
• The English language used in the manuscript was revised and amended.
• Highlighted the novelty and intrinsic causes in the revised manuscript.
• New references were added
• The points mentioned were indicated in the revised manuscript
• The conclusion was rewritten

Reviewer 4 Report

In this manuscript, three fungi were selected and identified to increase the in vitro ruminal degradability of oil palm fronds. The pretreatment using the enzyme extracted from 45 days of solid state fermentation increases the apparent rumen degradable carbohydrate by 35.29%. However, some experiments should be presented.

1) The authors claimed and identified enzymes. I suggest SDS-PAGE experiments should be added to test their conclusions that the enzyme activities have the same expression level in the fungi.

2) The English expression could be improved.

Author Response

• It is not possible to add SDS-PAGE to the current paper. However, the author have taken notes and SDS-PAGE will be added in future experiments. The author would like to express sincere gratitude for the suggestion.
• The English expression was improved.

Round 2

Reviewer 2 Report

Although the Authors have satisfactorily answered to questions 2) and 3) raised in the first round of my reviewing, they declare to have checked the standard errors in all illustrations reporting histograms and found them correct.

I remain of the opinion that it was almost impossible to obtain the same standard error for all the data reported in a graph.

For instance in Figure 1 the blue bars have the same standard error regardless the sample or the time analyzed. The same applies also for the orange and gray bars. The same behavior is observed also in Figures 2, 3, 9, 10.

Reviewer 3 Report

The revised version can be published to this journal. 

Reviewer 4 Report

I understand that it is difficult for further experiments in some cases. However, the authors should give some acceptable explanations.