Dynamic Changes in Polyphenols in Fruit Development of Red Flesh Apple ‘Hongxun 2’

Response to Reviewer 1 Comments

1. Summary

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.

2. Questions for General Evaluation

Reviewer’s Evaluation

Response and Revisions

Does the introduction provide sufficient background and include all relevant references?

Can be improved

[Thank you for your suggestions. We already improved the introduction]

Is the research design appropriate?

Yes

Are the methods adequately described?

Can be improved

[Thank you for your suggestions. We already improved the methods]

Are the results clearly presented?

Yes

Are the conclusions supported by the results?

Yes

3. Point-by-point response to Comments and Suggestions for Authors

Comments 1: Line 38- reference 1

Response 1: Thank you for pointing this out. There is a mistake in the PDF version, and there is references 1 in the word version. And we have revised it.

Comments 2: Line 83-88 the aim of the study should be better highlighted

Response 2: Agree. We have, accordingly, added the aim of this study to emphasize this point.

Comments 3: Line 106 how the supernatant absorbed? On what?

Response 3: Thank you for pointing this out. We have revised it. The supernatant was absorbed by pipette and was discarded.

Comments 4: Line 159-170 it is very difficult to follow the results. The authors should highlight the important results, the quantitative data it can be seen in Figure 1

Response 4: Thank you for pointing this out. We agree with this comment. Therefore, we have revised this paragraph, added the difference and variation trend between the two samples.

Comments 5: How the authors made the quantification for the five types of polyphenols included in Figure 2? For example, for anthocyanins? this should be mentioned in the "Methods" part

Response 5: Thank you for pointing this out. We have, accordingly, added the calculation method in the “Methods”.

Comments 6: Where are the individual polyphenols described with names? What is PROB 1? The polyphenolic component in Tabel 1-4 should be described with normal names somewhere in supplementary files

Response 6: Thank you for pointing this out. We have added the the full names corresponding to the abbreviations in the note to Table 1.

Comments 7: Line 364 “decrease degree decreased”

Response 7: Thank you for pointing this out. The expression here is not accurate enough, we have revised it.

Comments 8: Conclusion of the article is missing

Response 8: Thank you for pointing this out. We have added the conclusion.

Comments 9: What is the novelty of this work? This should be well defined in the article

Response 9: Thank you for pointing this out. We added the relevant content in the introduction. The novelty of this work is that the dynamic changes of polyphenols in the peel and pilp of green and red flesh apples from Xinjiang were compared, which provides a basis for the utilization of red flesh apples. At the same time, the classify of red flesh apples was discussed based on the composition and content of polyphenols.

Response to Reviewer 2 Comments

1. Summary

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.

2. Questions for General Evaluation

Reviewer’s Evaluation

Response and Revisions

Does the introduction provide sufficient background and include all relevant references?

Yes

Is the research design appropriate?

Yes

Are the methods adequately described?

Must be improved

[Thank you for your suggestions. We already improved the methods]

Are the results clearly presented?

Yes

Are the conclusions supported by the results?

Yes

3. Point-by-point response to Comments and Suggestions for Authors

Comments 1: Polyphenol extraction was done using 80% ethanol according to their earlier results. It might have been more interesting to use 70% ethanol acidified with hydrochloric acid. It is a common extractant, so the obtained results would be easier to compare with literature data.

Response 1: Thank you for pointing this out. Our laboratory has always used 80% ethanol to extract polyphenols, this is the method commonly used in our laboratory in recent years, it is an effenitve and stable method. The method you proposed may be better for exraction, we also made a comparison, it is easy to interrupt the glycoside after acidification, and the polyphenol component extracted is untable and can not be long-term preservation.

Comments 2: I think the authors should significantly rearrange the experimental part. I do not see experimental data on the identification and quantification of polyphenolic components. I do not see data on the use of analytical standards. Are these relative amounts determined according to some known polyphenol. I also don't see any information about the method of identification. There is no data on fragmentation either.

Response 2: Thank you for pointing this out. We have, accordingly, added relevant content and reference we published before, which had the specific quantitative methods and standard samples used in the experiment.