Nutritional Composition, Mineral Profiling, In Vitro Antioxidant, Antibacterial and Enzyme Inhibitory Properties of Selected Indian Guava Cultivars Leaf Extract

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

1. Data of extraction yield of different solvents and cultivars should be reported and discussed. 

2. All figures are not clear, please improve their quality.

3. The data in table 1 should be expressed as the mean ± standard deviation

4. The title of table 1 should be revised to "Elemental analysis of four Psidium guajava cultivars leaf extract"

5. More discussion in 2.3 and 2.4 are needed to confrim the major finding of this research and also its novelty.

6. Title should be revised as "Nutritional composition, mineral profiling, in vitro antioxidant, antibacterial and enzyme inhibitory properties of selected Indian Guava cultivars leaf extract" 

Author Response

RESPONSES FOR QUERIES TO REVIEWER 1

1. Data on extraction yield of different solvents and cultivars should be reported and discussed.

Ans.: As suggested, the results of extract yield were reported and discussed with other similar findings under results and discussion. Page No. 3; Line Nos. 119-126.

2. All figures are not clear, please improve their quality.

Ans.: The figures were restructured and the quality of images was enhanced with high resolution.

3. The data in Table 1 should be expressed as the mean ± standard deviation

Ans.: Thank you for your valuable comment. The mean ± standard deviation values were included in the revised manuscript for all the tables and figures.

4. The title of Table 1 should be revised to "Elemental analysis of four Psidium guajava cultivars leaf extract"

Ans.: Thank you for the valuable suggestion. The title of the table was revised as suggested.

5. More discussion in 2.3 and 2.4 is needed to confirm the major findings of this research and its novelty.

Ans.: As suggested, the results were discussed with similar findings of recent literature under the correlation studies. Page No. 15; Line Nos. 383-391.

6. The title should be revised as "Nutritional composition, mineral profiling, in vitro antioxidant, antibacterial and enzyme inhibitory properties of selected Indian Guava cultivars leaf extract"

Ans.: As suggested, the title is revised.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

Please check the attached file.

Comments for author File: Comments.pdf

Author Response

RESPONSES FOR QUERIES TO REVIEWER 2

1. Please give the full name for the abbreviation where it is used first

Ans.: As suggested, the full name has been provided in the page No. 1; Line Nos. 25-27.

2. Italic for the scientific names throughout the manuscript.

Ans.: All the scientific names have been italicized in the revised manuscript.

3. Put a comma after the word "assays,"

Ans.: Corrected. Page No. 1; Line No. 31.

4. please add ", respectively."

Ans.: Corrected. Page No. 1; Line No. 34.

5. Please give the tested bacteria names in the Abstract part.

Ans.: As suggested, the bacteria names were provided. Page No. 1; Line No. 38.

6. More discussion should be added about the antidiabetic activity and enzyme inhibitory activities.

Ans.: As suggested, more relevant discussion is included in the revised manuscript. Page No. 6; Line Nos. 212-218; 222-228.

7. The disc numbers on the agar surfaces should be explained and given as the Figure caption.

Ans.: Thank you for the valuable comment. The legend for the disc numbers were included in the figure legends. Page No. 9; Line Nos. 306-308.

8. Did the authors do the experiments once? There is no statistical analysis for antimicrobial activity studies.

Ans.: Thank you for the observation and query. We would like to inform that, we have carried out all the experiments in triplicate. The resultant values are included with standard deviation. We apologize for the error by not mentioning the same in the previous submission.

9. Capitalize the first letters

Ans.: Corrected.

10. Gram-negative bacteria (especially aeruginosa) is known to be resistant to amoxicillin. Do the authors have any reference for using amoxicillin as a control standard against P. aeruginosa? Which standards used?

Ans.: Thank you for the valuable suggestion. As advised different standards were used for the gram-positive (Amoxicillin) and gram-negative bacteria (Ciprofloxacin). The zone of inhibition study was repeated for the bacterium, P. aeruginosa with the antibiotic, Ciprofloxacin (Please refer the Figure 5) as suggested and modified in the revised version.

All other minor corrections made by the reviewer in the manuscript were carefully undertaken in the revised manuscript. 

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

The introduction should be restructured and supported with additional references because there are many literature on guava and the extracts of different parts of the plant.

Results and discussion sections need to be separated.

The quality of the figures is very poor. A significant improvement should be considered.

The study targeted the content of carbohydrates, protein, vitamin E, phenols and flavonoids which are somehow preliminary. A comparison of the contents and active ingredients using more sophisticated techniques is needed.

The enzymes inhibitory as well as the antioxidant and antimicrobial activities still couldn’t be linked to the active ingredients which are varied. Therefore, the determination of the active ingredients in the extracts should be considered. The most active extract of each cultivar could be used for the determination of active ingredients.

Overall, the study is preliminary and without determination of the exact ingredients, a conclusion couldn’t be drawn.

Comments on the Quality of English Language

The language should be improved. The manuscript contains many typos and grammatical errors.

Author Response

RESPONSES FOR QUERIES TO REVIEWER 3

1. The introduction should be restructured and supported with additional references because there are many literatures on guava and the extracts of different parts of the plant.

Ans.: Thank you for your in-depth observation of the manuscript. We took much care while revising the manuscript and the entire introduction section has been restructured and enriched with more detailed and recent literature.

2. Results and discussion sections need to be separated.

Ans.: According to the journal guidelines, the discussion section has been combined with the results.

3. The quality of the figures is very poor. A significant improvement should be considered.

Ans.: As suggested, the size and orientation of all the figures are restructured and enriched with quality images.

4. The study targeted the content of carbohydrates, protein, vitamin E, phenols, and flavonoids which are somehow preliminary. A comparison of the contents and active ingredients using more sophisticated techniques is needed.

Ans.: Thank you so much for your valuable comment. The possible compounds responsible for the reported biological properties were provided in the revised version. Page No. 2. 93-104. Hence, we have used four guava cultivars with three different solvents, we were not able to conduct sophisticated instrumental analysis for all the samples. With the advice of reviewers, we will look into this and carry out these studies in our future research.

5. The enzyme inhibitory as well as the antioxidant and antimicrobial activities still couldn’t be linked to the active ingredients which are varied. Therefore, the determination of the active ingredients in the extracts should be considered. The most active extract of each cultivar could be used for the determination of active ingredients.

Ans.: Thank you so much for your valuable comment. The possible compounds responsible for reported biological properties were provided in the revised version. Page No. 6. 222-228; Page No. 8, Line No. 272-278.

6. Overall, the study is preliminary and without determination of the exact ingredients, a conclusion couldn’t be drawn.

Ans.: We agree with the reviewers. However, the study is mainly based on the comparative analysis of nutritional composition and in vitro pharmacological properties of selected Indian guava cultivars. Hence, data on these aspects in the selected cultivars is lacking. Further research as suggested by the reviewer will be carried out in the future with the aim of identifying active ingredients.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript was significantly improved.

Reviewer 2 Report

Comments and Suggestions for Authors

Thank the authors for responses.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have addressed my comments.

Comments on the Quality of English Language

Minor typos and grammatical errors need to be corrected.