Exploring the Antioxidant, Antidiabetic, and Antimicrobial Capacity of Phenolics from Blueberries and Sweet Cherries

Round 1

Reviewer 1 Report

The paper is good. It is dedicated to determining the phenolic profiles of blueberry and sweet cherry. The authors also study antioxidant activity by different methods. It is not clear why the authors study the antimicrobial activity of the extracts, this issue needs some explanations. I wish the authors would make some correlation between antioxidant activity and some markers of the phenolic profile. 

Some corrections should be done.

1. Correct the sentence, considering that blueberry is not red

2. line 109 - how did the authors obtain the dry extract&

3/ Line 117-119, it is necessary to specify, for example, what total extract means.

4. DPPH test does not belong to the biological assay

5. Subchapter 3.1. It is recommended to provide formulas of the main  compounds which were detected, which are discussed in this paper

6. Which the purpose of the studies of measuring antimicrobial activity? It is necessary to discuss it

7/ Line 373-377 if te antimicrobial activity is weak, it is not good to write about antimicrobial therapy

8. It is unclear about obtaining non-colored fraction, colored fraction and total extract. It needs clarifying. This issue needs some additions.

The paper is worth attention, but it needs some corrections in order to improve the perception of the text

Comments for author File: Comments.pdf

The language I estimate as 3,5/5

Author Response

Dear Reviewer

First of all, we would like to thank your kind comments and compliments made on our manuscript. Following the comments received, the changes made by us are highlighted in the revised version, in accordance with the request. Even so, after each Reviewer’s comment, we indicated the main changes introduced and the corresponding lines. Thank you.

1. Correct the sentence, considering that blueberry is not red

Authors’ response: Thank you so much for your commentary, the Reviewer has total reason. In accordance with the request, we corrected it along with the article (please see now the revised version, thank you again).

2. line 109 - how did the authors obtain the dry extract 3. Line 117-119, it is necessary to specify, for example, what total extract means.

Authors’ response: Thank you so much for your commentary. In accordance with the request, we clarified this information (please see now lines 116, 123 and 124 of the revised version).

4. DPPH test does not belong to the biological assay

Authors’ response: Thank you so much for your commentary, the Reviewer has total reason. We corrected this topic (please see now line 149 of the revised version).

5. Subchapter 3.1. It is recommended to provide formulas of the main compounds which were detected, which are discussed in this paper

Authors’ response: Thank you so much for your suggestion, we added the chemical formulas of the main compounds (please see now lines 210, 211, 220, 221, 223, 227 and 228 of the revised version).

6. Which the purpose of the studies of measuring antimicrobial activity? It is necessary to discuss it

Authors’ response: Thank you very much for your comment. We added some sentences in the introduction and the discussion of the manuscript in order to explain the evaluation of this activity. This sentences can be found in lines 96-99, and 452-457.

7. Line 373-377 if the antimicrobial activity is weak, it is not good to write about antimicrobial therapy

Authors’ response: Thank you very much for your comment. We modified the manuscript avoiding to write about this possibility due to the mentioned lack of effective activity in comparison with commercial antibiotics. We added some sentences in now lines 418-421 and 445-448

8. It is unclear about obtaining non-colored fraction, colored fraction and total extract. It needs clarifying. This issue needs some additions.

Authors’ response: Thank you so much for your suggestion. We added new information regarding phenolics obtaining and also a reference very complete regarding this obtaining (please see now lines 120 and 121 of the revised version).

The paper is worth attention, but it needs some corrections in order to improve the perception of the text

Authors’ response: We would like to very thank your kind comment made on our manuscript. Thank you so much. Following the comments received, the changes made by us are highlighted in the revised version, in accordance with the request. Even so, after each Reviewer’s comment, we indicated the main changes introduced and the corresponding lines. Thank you.

Author Response File: Author Response.pdf

Reviewer 2 Report

This manuscript is a research on. " Exploring the antioxidant, antidiabetic and antimicrobial capacity of phenolics from blueberries and sweet cherries”. the study is unacceptable in its current form, manuscript needs to minor revision. File was attached.

Comments for author File: Comments.pdf

Minor editing of English language required

Author Response

First of all, we would like to thank your kind comments and compliments made on our manuscript. Following the comments received, the changes made by us are highlighted in the revised version, in accordance with the request. Even so, after each Reviewer’s comment, we indicated the main changes introduced and the corresponding lines. Thank you.

Below I list some of the main causes.

1. Please indicate in the abstract section against which microorganisms the antimicrobial activity was determined. “Four Gram-positive strains (Enterococcus faecalis ATCC 29212, 160 Bacillus cereus ATCC 11778, Listeria monocytogenes LMG 16779, Staphylococcus aureus ATCC 161 25923), and five Gram-negative strains (Salmonella enterica subsp. Entérica ATCC 13311 162 serovar Typhimurium, Klebsiella pneumoniae ATCC 13883, Proteus mirabilis CECT 170, Ser- 163 ratia marcescens CECT 159, and Acinetobacter baumannii LMG 1025) “

Authors’ response: Thank you so much for your commentary, this information was added (please see now line 36 to 40 of the revised version).

2. Please specify chemical properties for methanol and acetonitrile used in the experimental stages in the chemical section. for example; degree of purity...

Authors’ response: Thank you so much for your commentary, this information was added (please see now lines 94 and 101 of the revised version).

3. In the chromatographic analysis section, the wavelengths measured should be added specifically.

Authors’ response: Thank you so much for your commentary, this information was added (please see now lines 143 and 144 the revised version).

4. There is a need for a literature comparison in a new table for the amount of antimicrobial, antioxidant and phenolic obtained. Results should be compared with analysis findings of different fruits.

Authors’ response: Thank you so much for your commentary. As recommended, we deeper the discussion of the results; however, after being discussed among the authors, we decided not to put the comparations in a table in order to simplify the article. We hope the Reviewer understand (please see now lines 235-239, 266-271, 266-271, 278-282, 297-300, 367-371 of the revised version).

5. Many features of known fruits such as anti-inflammatory, antioxidant, antimicrobial and phenol amounts come to the fore and very successful analysis findings are encountered. In the introduction section, the authors argue that this research has been conducted for the first time in the literature. Therefore, a detailed explanation is required to make comparisons about other fruits and to emphasize the importance of this research. The following articles will help you “Encapsulation and antibacterial studies of goji berry and garlic extract in the biodegradable chitosan G Baysal, HS Olcay, Ç Günneç Journal of Bioactive and Compatible Polymers, 2023; 38, 3, https://doi.org/10.1177/08839115231157097

Authors’ response: Thank you so much for your commentary. As recommended, we deeper the discussion of the results (please see now the section “Discussion” of the revised version). Also, we included a sentence in the introduction.

6. Please note that the results of gram-negative and gram-positive bacteria in the antimicrobial analysis findings are different.

Authors’ response: Thank you very much for your comments. We added this information in lines 410-413.

7. In the conclusion section, give a brief summary of the analysis findings of the study.

Authors’ response: Thank you so much for your commentary, this information was added (please see now the section “Conclusions” of the revised version).

Author Response File: Author Response.pdf

Reviewer 3 Report

The paper by Goncalves et al. reports a study evaluating  some biological properties of phenolics from blueberries, with relevance to human health. The study reports the analysis of the composition of Blueberries cv. Legacy and cv. Duke, which identified a series of active compounds, mostly phenolics. All extracts showed significant antioxidant properties, the ability to inhibit the activity of α-glucosidase enzyme and some antimicrobial activity.

The methodology used appears correct. The results are interesting.

The paper is clearly written and understandable. I suggest to revise the English language and to correct several typos.

 Specific comments

 Line 52: add the unit after 552.2

I suggest to revise the English language and to correct several typos.

 Author Response

Dear reviewer

First of all, we would like to thank your kind comments and compliments made on our manuscript. Following the comment received, we added a picture of each sample, please see now figure 1 of the revised version. Thank you so much!

Best regards

Author Response File: Author Response.pdf

Reviewer 4 Report

The research presented in the article Exploring the antioxidant, antidiabetic and antimicrobial capacity of phenolics from blueberries and sweet cherries was presented by the authors in an interesting and insightful way. The article is based on 71 literature references and own research.

The abstract succinctly shows the content. The main result is the detection of anthocyanins in blueberry and sweet cherry, quercetin aglycone and chlorogenic acids. Antioxidant properties of these compounds have been confirmed.

Phenolic compounds extraction was prepared and was analyzed by chromatographic analysis. The quantification of the known compounds (132) was carried out by comparing their retention times and ultraviolet–visible spectra with spectra of those authentic standards. Antioxidant assays was used and was done spectrophotometrically. 

Research has shown that red fruit compounds have high potential for inclusion in pharmaceuticals, dietary supplements and nutraceuticals.

The work shows the accuracy of the experiments carried out and thus the repeatability of the results

I will sugest to add a few pictures of samples.

Thank you

Author Response

Dear reviewer,

First of all, we would like to thank your kind comments and compliments made on our manuscript. Following the comment received, we added a picture of each sample, please see now figure 1 of the revised version. Thank you so much!

Best regards

Author Response File: Author Response.pdf

Reviewer 5 Report

The study titled "Investigating the potential antioxidant, antidiabetic, and antimicrobial effects of phenolics found in blueberries and sweet cherries" aimed to explore the antioxidant and antimicrobial properties of two fruits. However, the authors relied solely on qualitative parameters such as correlation of the properties with total and colored extract, which vary from sample to sample and method of extraction. To ensure more accurate and reliable results, it is recommended to analyze the functional groups of the extracted material, such as phenolic OH, and correlate the antioxidant and antimicrobial properties with the chemical structures and functional groups of the extracts. This approach would eliminate the dependence on the sample's extraction method and sample's variation from different locations and provide more comprehensive data.

good

Author Response

Dear reviewer

First of all, we would like to thank your kind comments and compliments made on our manuscript. Following the comments received, the changes made by us are highlighted in the revised version, in accordance with the request (please see now lines 252-254, 299-304 and 354 to 356 the revised version). Thank you very much for your invaluable opinion and comments

Best regards

Author Response File: Author Response.pdf

Round 2

Reviewer 5 Report

thank you for your update. despite it is not as good as I expected, however, is enough for this article. For your future articles, please try to make a connection between antimicrobial/antioxidant properties with structure of extracted material. 

Acceptable