Photocatalytic, Antimicrobial, and Cytotoxic Efficacy of Biogenic Silver Nanoparticles Fabricated by Bacillus amyloliquefaciens
, Saad El-Din Hassan 1, Mohammed F. Hamza 2,3, Samy Selim 4,*, Mohammed S. Almuhayawi 5,6, Mohammed H. Alruhaili 5,7, Muyassar K. Tarabulsi 8, Mohammed K. Nagshabandi 8 and Amr Fouda 1,2,*Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe manuscript describes the synthesis of silver nanoparticles by ecofriendly method. Various applications of the synthesized nanoparticles are extensively studied. Especially, the determination of antimicrobial and anticancer activities sounds to be highly significant.
The references are adequate and the overall presentation of the work by authors is excellent. The manuscript can be accepted for publication after revision. Some specific comments that needs to be addressed are given below:
1) What is the advantage of utilizing Bacillus amyloliquefaciens for the synthesis of silver nanoparticles when compared to other reported methods for the synthesis of Ag-NPs?
2) I would like to know whether the authors used any standard drug as the reference while determining the antibacterial and anti-fungal activities.
3) Similarly, the details about reference standard for anticancer studies is also missing.
4) I would like to know why the authors decided to determine MIC values for antimicrobial studies and IC50 values for anticancer activity evaluation.
5) There are many "badly worded phrases" and grammatical errors which needs to be corrected before publishing this manuscript.
After addressing these comments, the manuscript may be published.
Comments on the Quality of English Language
Moderate editing of English is needed.
Author Response
Thank you for your comments. We revised the manuscript based on the reviewer's comments. Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsIn the manuscript, the authors used the ecological production of silver nanoparticles (Ag-NPs) using the biomass nanoparticles Fa. 2. The synthetic Ag-NPs can efficiently degrade methylene blue under sunlight and UV irradiation, meanwhile, biogenic Ag-NPs also show excellent biological activity. Overall, the bacterial-synthesized Ag-NPs have multiple functions that can be used for environmental catalysis and biomedical applications. But the whole article is difficult to understand, I suggest rejection.
1. There are three research content of this manuscript. It is not easy to make it clear.
2. The language and figure of the article needs further revision and polishing. They are difficult to understand.
3. It is recommended to adjust the legend of the bars in Figure 8 and the ordinate inhibition rate is a unit error.
4. Are the conditions for the quenching experiment either sunlight or UV? Please indicate the reaction conditions.
5. One of the possible reasons for Ag degradation of MB by the manuscript-NPs is due to the adsorption of the catalyst, please provide data on the adsorption effect of the catalyst.
Comments on the Quality of English LanguageThe whole article is difficult to understand.
Author Response
Thank you for your comments. We revised the manuscript based on the reviewer's comments. Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors1.The biomass filtrate of the endophytic bacterial strain Bacillus amyloliquefaciens Fa.2 was utilized for the eco-friendly production of silver nanoparticles (Ag-NPs). The content has a certain innovative. But the experimental design was incomplete, which is not enough to prove and support the photocatlytic, antimicrobial and cytotoxic efficacy. For example, the experiment of minimum bactericidal concentration should be added in the experiment of antibacterial activity. Bacteriostatic zone experiment and images.
2. 2.2.5 speaking of stability, please add AgNPs stability test.
3.In photocatalytic of MB, the UV diffuse reflection experiment should be supplemented to calculate the bandgap width. Otherwise, there is no basis for the explanation of photocatalysis mechanism.
4. The actual amount of silver needs to be determined by ICP or other methods. In addition, XPS experiments need to be added to analyze the valence of silver.
5. What is CFF? The first appearance of CFF requires a full name.
6. What is the bactericidal mechanism of Ag NPs? Please add the relevant description.
7. This paper covers too many properties and has no focus. What is the correlation between cytotoxic effects, photocatalysis and bactericidal functions? In particular, the review in the introduction section is incomplete and does not raise specific or relevant scientific questions.
8.This paper covers too much content and has no focus. In particular, the introduction is incomplete and does not raise relevant scientific questions. And the logic of introduction is not clear enough.
Comments on the Quality of English LanguageWhat is CFF? The first appearance of CFF requires a full name.
Author Response
Thank you for your comments. We revised the manuscript based on the reviewer's comments. Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 4 Report
Comments and Suggestions for AuthorsThis is a comprehensive study that highlights the exciting multi-functional capabilities of the Bacillus amyloliquefaciens-derived Ag-NPs, including photocatalysis, antimicrobial activity, and cancer cell targeting. The green, bacterial synthesis approach is an environmentally-friendly route to producing these versatile nanoparticles. Further exploration of their real-world applications in environmental remediation and biomedical fields is warranted. This can be published after fixed.
1: the 11.6% was decreased after five cycles, which will be better to comparison with others in the literatures.
2: The size distribution may need more data for the fitting.
3: How about the catalysis work for others dyes.
4: Some background about the advanced catalysts was suggested to introduced , you may references the following references: doi.org/10.1007/s40820-023-01091-9; doi.org/10.1002/EXP.20230050; doi.org/10.1016/j.apmate.2023.100117; https://doi. org/10.1002/cnl2.96; doi.org/10.1016/j.esci.2023.100206;doi.org/10.1002/adfm.202316834; doi.org/10.1038/s41467-021-26025-0
Author Response
Thank you for your comments. We revised the manuscript based on the reviewer's comments. Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsThis manuscript can be accepted.
