Phytochemical Analysis and Specific Activities of Bark and Flower Extracts from Four Magnolia Plant Species

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I have read the submission entitled 'Phytochemical Constituents and Antibacterial Activity of Bark  2 and Flowers Extracts of Four Magnolia Plant Species'. The study is well written and design good. The constituents of four species and the activities were evaluated. However, the following comments should be considered and revised before publication.

1. In the introduction section, ther are too much paragraphs, please revise it consice and logically.

2. some text errors should be revised.

3. Too much references cited in the introduction section.

4. what is the most different compound in the four Magnolia species? and is there any activity-structure relationship?

5. please edit figure by using professional software.

Author Response

The manuscript entitled "Phytochemical Constituents and Antibacterial Activity of Bark and Flowers Extracts of Four Magnolia Plant Species" has been revised according to the reviewer’s suggestions. We greatly appreciate your comprehensive, useful, and valuable suggestions and comments, which have been very helpful in improving the manuscript! We have endeavored to respond to all suggestions and comments individually addressed in this cover letter and the revision of the manuscript.

 

Response to Reviewer 1 Comments

 

 

The manuscript entitled "Phytochemical Constituents and Antibacterial Activity of Bark and Flowers Extracts of Four Magnolia Plant Species" has been revised according to the reviewer’s suggestions. We greatly appreciate your comprehensive, useful, and valuable suggestions and comments, which have been very helpful in improving the manuscript! We have endeavored to respond to all suggestions and comments individually addressed in this cover letter and the revision of the manuscript.

 

Point 1: In the introduction section, there are too much paragraphs, please revise it consice and logically.

Response 1: The Introduction section has been revised.

 

Point 2: Some text errors should be revised.

Response 2: The text has been revised to eliminate textual errors.

 

Point 3: Too much references cited in the introduction section.

Response 3: The number of references in the Introduction section has been reduced.

 

Point 4: What is the most different compound in the four Magnolia species? And is there any activity-structure relationship

Response 4: In all four Magnolia species under study, flavonoids have been identified in substantial concentrations. These compounds demonstrate a distinct and significant role in enhancing the antioxidant and antimicrobial efficacy of the plant extracts.

 

Point 5: Please edit figure by using professional software.

Response 5: The figures have been revised.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The paper entitled "Phytochemical Constituents and Antibacterial Activity of Bark and Flowers Extracts of Four Magnolia Plant Species" are average research article with the main goal of testing phytochemicals and their antimicrobial effect on selected mangolia plants. 

Since this paper did not involve any novel moment in the investigation, I will give some crucial suggestions for improving the quality of the obtained results. However, in this form, the paper is not good enough to be published in the Horticulturae and can be considered only after revision of the whole concept.

- If you tested only MIC with a limited number of bacteria, the title can not be "...antibacterial activity". You did not show any in vitro test for determination of antibacterial activity. Minimal inhibitory concentration is related only to the potential of plants to induce the inhibitory effect. Also, you did not determine if the gained effect belongs to the group of the bacteriostatic or bacteriocide effect. The complete paper must be revised in this direction. A few more methods for antimicrobial testing have to be done and presented in the paper: 1. disk-diffusion test (with photos of the inhibitory zones), 2. MIC, 3. Time-kill kinetics study; 4. Antibiofilm and antiadhesion potential; 5. Statistical analysis.

Also, all these steps must be accompanied by an explanation of why the bacteria used were chosen and their importance from the point of view of future application.

Changing the keywords can contribute to better visibility of the work (avoid using the same words present in the title)

The Introduction part can be written with 15 references, so deleting all others through repetitions must be done. 

Antioxidant evaluation has to have a minimum of three tests, for example, DPPH, ABTS, RP or SoA in order to evaluate this biological activity in vitro.

 

Comments on the Quality of English Language

Minor editing of English language required

Author Response

The manuscript entitled "Phytochemical Constituents and Antibacterial Activity of Bark and Flowers Extracts of Four Magnolia Plant Species" has been revised according to the reviewer’s suggestions. We greatly appreciate your comprehensive, useful, and valuable suggestions and comments, which have been very helpful in improving the manuscript! We have endeavored to respond to all suggestions and comments individually addressed in this cover letter and the revision of the manuscript.

 

Response to Reviewer 2 Comments

 

 

The manuscript entitled "Phytochemical Constituents and Antibacterial Activity of Bark and Flowers Extracts of Four Magnolia Plant Species" has been revised according to the reviewer’s suggestions. We greatly appreciate your comprehensive, useful, and valuable suggestions and comments, which have been very helpful in improving the manuscript! We have endeavored to respond to all suggestions and comments that are individually addressed in this cover letter and in the revision of the manuscript.

 

Point 1: If you tested only MIC with a limited number of bacteria, the title can not be "...antibacterial activity". You did not show any in vitro test for determination of antibacterial activity. Minimal inhibitory concentration is related only to the potential of plants to induce the inhibitory effect. Also, you did not determine if the gained effect belongs to the group of the bacteriostatic or bacteriocide effect. The complete paper must be revised in this direction. A few more methods for antimicrobial testing have to be done and presented in the paper: 1. disk-diffusion test (with photos of the inhibitory zones), 2. MIC, 3. Time-kill kinetics study; 4. Antibiofilm and antiadhesion potential; 5. Statistical analysis. Also, all these steps must be accompanied by an explanation of why the bacteria used were chosen and their importance from the point of view of future application.

Response 1: The purpose of the paper was to provide an overview of the properties of these extracts. The additional tests suggested by the reviewer formed the basis of an article strictly focused on the microbiological aspect, which is in the process of being published, and thus they cannot be included in subsection 3.3. However, the expression regarding antibacterial activity has been corrected according to the reviewer's suggestions (the potential of plants to induce the inhibitory effect) and why these bacteria were selected for establishing the MIC. The title has been modified to correspond with the reviewer's observations: 'Phytochemical constituents and their specific activity of bark and flower extracts of four magnolia plant species'.

 

 

Point 2: Changing the keywords can contribute to better visibility of the work (avoid using the same words present in the title).

Response 2: The modification has been made following the reviewer's suggestions.

 

Point 3: The Introduction part can be written with 15 references, so deleting all others through repetitions must be done. 

Response 3: The modification has been made following the reviewer's suggestions.

 

 

Point 4: Antioxidant evaluation has to have a minimum of three tests, for example, DPPH, ABTS, RP or SoA in order to evaluate this biological activity in vitro.

Response 4: The subsection has been supplemented with two additional antioxidant tests following the reviewer's suggestion.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

In the presented publication, the authors have taken up the interesting topic of phytochemical studies of four magnolia species. The bark and flowers were studied. Microbiological tests were also carried out to check the antibacterial properties of ethanol-water extracts from the bark and flowers of the individual species. The research conducted is expected to enable the use of magnolia extracts as cosmetics with biological and antibacterial effects.

The paper needs several additions and changes in the organisation of the text. The phytochemical section will also need to be supplemented with the necessary data in the quantitative analysis of polyphenols.

In the introduction, which describes the previous use of magnolia, a clearly stated aim of the research described in the publication should be added.

In section 2.2, the authors subject the concentrated extracts to redissolution in distilled water (line134).

To what concentration were the extracts concentrated? This is important in order to perform quantitative determinations of compounds.

Is the solubility of the polyphenols in water sufficient? Has it been checked? Why was a mixture of water and ethanol not used?

In the description of the spectophotometric study, the reaction mixture with DPPH has a volume of 200 microm. Was this amount sufficient to fill the measuring cuvette? What are the dimensions of the cuvette used? (line 150)

To determine the amount of phenolic acids, were calibration curves made for each acid? You need to specify the concentration ranges in which the calibration curves were prepared. Or was another method used? Which one? (line from 171)

What dillutant was used in antibacterial activiy investigations? (line210)

There are also some parts of the text which shoulc be placed i discussion section, in my opinion. For example: from line 279 to 285, 442-480, 550-565, 629-639, 666-677.

In the discussion , the chemical composition was repeated several times without literature references. Authors' results should be extracted and other researchers should be quoted. The entire subsection should be edited - abbreviate what it currently contains and add sections placed in the results.

Equations are included in the figures. What do they relate to? They are not equations describing standard curves. The data shown are for different raw materials. Please clarify their meaning or remove the equations from the graphs in Figures 1 to 4.

Comments for author File: Comments.pdf

Author Response

The manuscript entitled "Phytochemical Constituents and Antibacterial Activity of Bark and Flowers Extracts of Four Magnolia Plant Species" has been revised according to the reviewer’s suggestions. We greatly appreciate your comprehensive, useful, and valuable suggestions and comments, which have been very helpful in improving the manuscript! We have endeavored to respond to all suggestions and comments individually addressed in this cover letter and the revision of the manuscript.

 

Response to Reviewer 3 Comments

 

The manuscript entitled "Phytochemical Constituents and Antibacterial Activity of Bark and Flowers Extracts of Four Magnolia Plant Species" has been revised according to the reviewer’s suggestions. We greatly appreciate your comprehensive, useful, and valuable suggestions and comments, which have been very helpful in improving the manuscript! We have endeavored to respond to all suggestions and comments that are individually addressed in this cover letter and in the revision of the manuscript.

 

Point 1: The phytochemical section will also need to be supplemented with the necessary data in the quantitative analysis of polyphenols.

Response 1: The necessary additions have been implemented in the phytochemical section, following the reviewer's suggestion.

 

Point 2: In the introduction, which describes the previous use of magnolia, a clearly stated aim of the research described in the publication should be added.

Response 2: In the introduction, the aim of the study has been added as per the recommendations.

 

Point 3: Line 134 - In section 2.2, the authors subject the concentrated extracts to redissolution in distilled water. To what concentration were the extracts concentrated? This is important in order to perform quantitative determinations of compounds.

Response 3: The concentrations were carried out at a ratio of 1:1 (1 mg of dry extract to 1 mL of distilled water).

 

Point 4: Is the solubility of the polyphenols in water sufficient? Has it been checked? Why was a mixture of water and ethanol not used?

Response 4: Extraction trials utilizing a range of solvents for polyphenols have been executed. The comparative outcomes of these trials are being addressed in a separate, forthcoming research publication.

 

Point 5: Line 150 - In the description of the spectophotometric study, the reaction mixture with DPPH has a volume of 200 microm. Was this amount sufficient to fill the measuring cuvette? What are the dimensions of the cuvette used?

Response 5: The transcription error has been corrected (250µg + 1750 µL). Cuvettes with a dimension of 10mm were used.

 

Point 6: From Line 171 - To determine the amount of phenolic acids, were calibration curves made for each acid? You need to specify the concentration ranges in which the calibration curves were prepared. Or was another method used? Which one?

Response 6: Standard calibration curves were employed. The requested details have been added to the text.

 

Point 7: What dillutant was used in antibacterial activiy investigations?

Response 7: In the antibacterial activity studies, 1:1 aqueous extracts were utilized. The text has been duly updated to include this specific detail.

Point 8: From line 279 to 285, 442-480, 550-565, 629-639, 666-677. There are also some parts of the text which should be placed in discussion section, in my opinion.  

Response 8: The paragraphs have been relocated in accordance with the reviewer's suggestions.

 

Point 9: In the discussion , the chemical composition was repeated several times without literature references. Authors' results should be extracted and other researchers should be quoted. The entire subsection should be edited - abbreviate what it currently contains and add sections placed in the results.

Response 9: The paragraphs have been modified in line with the reviewer's suggestions.

 

Point 10: Equations are included in the figures. What do they relate to? They are not equations describing standard curves. The data shown are for different raw materials. Please clarify their meaning or remove the equations from the graphs in Figures 1 to 4.

Response 10: The equations in Figures 1-4 have been revised for clarity and accuracy in accordance with the feedback.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

All comments were addressed in this version.

Author Response

Dear Reviewer,

I would like to express my sincere gratitude for the time and effort you have dedicated to reviewing our manuscript. Your insightful comments and constructive feedback have been invaluable in enhancing the quality and clarity of our paper. We deeply appreciate your detailed suggestions, which have guided us in making significant improvements to our work.

Your expertise and thorough review have not only contributed to the betterment of this article but have also provided us with a learning opportunity to further our research skills and understanding in our field.

Thank you once again for your invaluable contribution to our work. We are truly grateful for your support and guidance.

Best regards,

Reviewer 2 Report

Comments and Suggestions for Authors

Thank you for accepting my suggestions. 

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

Dear Reviewer,

I would like to express my sincere gratitude for the time and effort you have dedicated to reviewing our manuscript. Your insightful comments and constructive feedback have been invaluable in enhancing the quality and clarity of our paper. We deeply appreciate your detailed suggestions, which have guided us in making significant improvements to our work.

Additionally, we have undertaken minor editing of the English language to ensure that the text is as clear and effective as possible.

Your expertise and thorough review have not only contributed to the betterment of this article but have also provided us with a learning opportunity to further our research skills and understanding in our field.

Thank you once again for your invaluable contribution to our work. We are truly grateful for your support and guidance.

Best regards,