Bio-Mediated Zinc Oxide Nanoparticles through Tea Residue: Ecosynthesis, Characterizations, and Biological Efficiencies
Round 1
Reviewer 1 Report (Previous Reviewer 1)
The manuscript has been improved a lot compared to the former version. But revisions are still needed before acceptance. The authors should check the format carefully and make necessary modifications. I recommend the authors use the journal template when preparing the revised version.
Abstract: The background of this study should be introduced to the readers.
Line 30: what is the MTT test?
Line 82-83 Numbers in the chemical formula should be subscripted.
Line 93 60ºC--- 60 ºC. A space is needed between the value and the unit. Other places need to be checked as well.
Table 1 Adding the analysis of significance difference.
Line 260 Zn2+ superscript
The reference format also needs correction. Please follow the author's guideline of the journal.
Author Response
As per your suggestion has been carried out.
Author Response File: 
Author Response.docx
Reviewer 2 Report (Previous Reviewer 2)
Sustainability-2037945 quality has been greatly improved after a lot of modification by the author. It is very interesting and give the valuable information to the researchers and readers. The subject of the manuscript is consistent with the scope of the Journal. The English language is fluent and easy to read. Thus, I suggested that the manuscript need to be minor revised before it is accepted by this journal.
1. Line 25-29: This sentence should be rewritten or shorten.
2. Line 30: “MMT” should be full name. Please check the full text for the first time abbreviations appear.
3. Table 1: Mean values should keep two decimal places. “0” of “09 or 08” should be deleted.
4. The significance of data differences between different treatments should be added to increase readability.
5. The logic and neat of introduction need to be further improved.
Author Response
As per your suggestion has been carried out.
Author Response File: Author Response.docx
Reviewer 3 Report (Previous Reviewer 3)
Although the authors revised this manuscript according to my comments very carefully. Unfortunately, a paper is just published about the controlled growth of ZnO nanoparticles using ethanolic root extract of Japanese knotweed and their photocatalytic and antimicrobial properties (RSC Adv., 2022, 12, 31235-31245), which is very similar to your study. Thus, the authors should emphasize their novelty compared with other literatures.
Author Response
As per your suggestion has been carried out.
Author Response File: Author Response.docx
Reviewer 4 Report (Previous Reviewer 4)
The authors have made the requested corrections, It is enough just to homogenize the references in the list.
Author Response
As per your suggestion has been carried out.
Author Response File: Author Response.docx
Round 2
Reviewer 3 Report (Previous Reviewer 3)
OK, the manuscript is fine to be accepted.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
The manuscript entitled " Bio-Fabrication of zinc oxide nanoparticles using tea residue: Eco synthesis, Characterizations and biological efficiencies " reported a method to generate ZnO NPs using tea residue. The characterizations and effects on anti-microbial and cytotoxicity to human lung cancer cells of the ZnO NPs were investigated. The results contain something novel. However, I think this manuscript is not prepared to publish in its current status.
The abstract is weak because the background is absent and the language is not concise and powerful.
The introduction section also didn‘t adequately indicate the information on ZnO-NPs. The authors should introduce the application and advantages of ZnO-NPs more fully and the deficiencies of current ZnO-NPs production methods.
Meterials and methods: 2.1 chemical and 2.2 Collection and preparation of tea residue extracts should be described in more detail. The manufacturer of chemicals and the tea residue's basic physical and chemical properties should be recorded.
The text contained format issues, e.g., Line 54, Line 87, Line 91, Line 117, Line 215.
ppm is not a standard unit. e.g., Line 262.
Table 1 Difference significance analysis is needed.
The figures are not clear.
The conclusion is weak. Please rewrite.
Author Response
Reviewer 1
Queries 1: The abstract is weak because the background is absent and the language is not concise and powerful.
Author reply: As per your suggestion carried out
Queries 2: The introduction section also didn‘t adequately indicate the information on ZnO-NPs. The authors should introduce the application and advantages of ZnO-NPs more fully and the deficiencies of current ZnO-NPs production methods.
Author reply: As per your suggestion carried out
Queries 3: Materials and methods: 2.1 chemical and 2.2 Collection and preparation of tea residue extracts should be described in more detail. The manufacturer of chemicals and the tea residue's basic physical and chemical properties should be recorded.
Author reply: As per your suggestion carried out
Queries 4: The text contained format issues, e.g., Line 54, Line 87, Line 91, Line 117, Line 215.
Author reply: As per your suggestion carried out
Queries 5: ppm is not a standard unit. e.g., Line 262.
Author reply: Typographical error has been removed.
Queries 6: Table 1 Difference significance analysis is needed.
Author reply: As per your suggestion carried out
Queries 7: The figures are not clear.
Author reply: As per your suggestion carried out
Queries 8: The conclusion is weak. Please rewrite.
Author reply: As per your suggestion carried out
Reviewer 2 Report
Manuscript Title: Bio-Fabrication of zinc oxide nanoparticles using tea residue: Eco synthesis, Characterizations and biological efficiencies
The present manuscript “Bio-Fabrication of zinc oxide nanoparticles using tea residue: Eco synthesis, Characterizations and biological efficiencies”, has established a simple, inventive, and affordable green technique for generating ZnO nanoparticles, which has been evidenced that the chosen nanoparticle combination has enhanced antimicrobial, anticancer and photocatalytic activities. And further investigation should be conducted in the future. The study fits within the scope of the Journal and will also contribute to the existing scientific database. However, the authors should address the major concerns raised during the review process stated below and further investigation should be conducted in the future.
The following specific comments are observed:
1. I would like to suggest general editing of the English language especially in introduction and discussion sections, and the authors should consider making reading more agile.
2. Introduction is too shallow and more states should be added for the justification of the study.3. In the Discussion, as a whole, there is little depth and breadth in the discussion, little focus on the theme of this study, and little explanation and comparison of the key results to other references. The parts should be improved the internal logic and highlight the new findings or insights in this study.
4. The number of decimal points in the manuscript should be consistent.
5. If possible give a separate section for "Statistical analysis”.6. The expression of the units for “g/ml or µg/ml-1” should be unified and checked in the manuscript.
7. The format of the article should also be checked. For example, there should be spaces between the numbers and the parentheses (Line 180).
Author Response
Queries 1: I would like to suggest general editing of the English language especially in introduction and discussion sections, and the authors should consider making reading more agile.
Author reply: As per your suggestion carried out
Queries 2: Introduction is too shallow and more states should be added for the justification of the study.
Author reply: As per your suggestion carried out
Queries 3: In the Discussion, as a whole, there is little depth and breadth in the discussion, little focus on the theme of this study, and little explanation and comparison of the key results to other references. The parts should be improved the internal logic and highlight the new findings or insights in this study.
Author reply: As per your suggestion were carried out
Queries 4: The number of decimal points in the manuscript should be consistent.
Author reply: As per your suggestion were carried out
Queries 5: If possible give a separate section for "Statistical analysis”.
Author reply: As per your suggestion included.
Queries 6: The expression of the units for “g/ml or µg/ml-1” should be unified and checked in the manuscript.
Author reply: As per your suggestion were carried out
Queries 7: The format of the article should also be checked. For example, there should be spaces between the numbers and the parentheses (Line 180).
Author reply: As per your suggestion were carried out
Reviewer 3 Report
The authors of this manuscript applied aqueous tea residue extract as the reductant and stabilizing agent for green synthesis of ZnO nanoparticles. Then they used various characterization methods to analyse the products, and investigate their antimicrobial capability, cytotoxicity, and photocatalytic activity. However, the idea of using tea extract for ZnO synthesis has been reported previously (ACS Omega, 2022, 7, 31658−31666; Cogent Chemistry, 2018, 4, 1469207; F1000Research, 2021, 10, 1077). Thus, I think this work lacks novelty for publishing in Sustainability. Moreover, this manuscript is not prepared well in the present form. Other major comments are listed as below:
1. The introduction part does not give enough useful information about the background. For example, the existing approaches for ZnO synthesis should be summarized.
2. In the part of materials and methods, I cannot find the detailed synthesis process of ZnO nanoparticles by using tea extract.
3. What is the mechanism of ZnO formation from tea extract? The authors should study the detailed reaction process.
4. What are the possible influence factors for the preparation of ZnO nanoparticles? The authors should give a discussion.
5. Transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS) should be added to characterize the ZnO nanoparticles.
6. The antimicrobial and cytotoxicity experiments should have a discussion about the mechanisms. And the authors should discuss the environmental and biosafety of their nanomaterials.
7. The photocatalytic experiment should give more results and in-depth discussion.
8. There are some language errors in the manuscript. The manuscript should be carefully checked by native speakers.
Author Response
Queries 1: The introduction part does not give enough useful information about the background. For example, the existing approaches for ZnO synthesis should be summarized.
Author reply: As per your suggestion were carried out
Queries 2: In the part of materials and methods, I cannot find the detailed synthesis process of ZnO nanoparticles by using tea extract.
Author reply: As per your suggestion included.
Queries 3: What is the mechanism of ZnO formation from tea extract? The authors should study the detailed reaction process.
Author reply: As per your suggestion included.
Queries 4: What are the possible influence factors for the preparation of ZnO nanoparticles? The authors should give a discussion.
Author reply: ZnC₄H₆O₄ Zn(CH3COO)2+(H2O)2
Tea residue control the aggregation of ZnO in the range of nanosize
Queries 5: Transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS) should be added to characterize the ZnO nanoparticles.
Author reply: As per reviewer’s suggestion Transmission electron microscopy (TEM) are carried out and included in the revised manuscript. X-ray photoelectron spectroscopy study is not carried because in this study we didn’t try any dopant or foreign material in the preparation of ZnO nanoparticles. Instead EDAX analysis is carried out.
Queries 6: The antimicrobial and cytotoxicity experiments should have a discussion about the mechanisms. And the authors should discuss the environmental and biosafety of their nanomaterials.
Author reply: As per your suggestion included.
Queries 7: The photocatalytic experiment should give more results and in-depth discussion.
Author reply: As per your suggestion included.
Queries 8: There are some language errors in the manuscript. The manuscript should be carefully checked by native speakers.
Author reply: As per your suggestion carried out
Reviewer 4 Report
Bio-Fabrication of zinc oxide nanoparticles using tea residue: Eco synthesis, Characterizations and biological efficiencies
· Authors should pay attention to the use of capital letters in the title please follow the template of the journal.
· The authors are requested to use new references in the manuscript and especially in the introduction.
· In the abstract as well as in the introduction, please quote the full name (nanoparticles) in the text before citing them NP.
· Introduction: line 54 : The NPs exhibit great medicinal applications in targeted drug administration, (18) wound healing and bioimaging: the number 18??
· Before line 49, it was better to cite some works on the techniques applied especially for the production of ZnO-NPs.
· (C2H3O2)2.2H2O), Please write the exact formulas with indices
· DMEM medium: Please give the full name of this abbreviation.
· Line 200-203: please review the position of these sentences.
· Figure 5: capitals in the y-axis.
· Figure 7 is illegible please redo it.
· In the conclusion, please add a section on the perspectives that can be drawn from this work, especially on an industrial scale.
Author Response
Reviewer 4
Bio-Fabrication of zinc oxide nanoparticles using tea residue: Eco synthesis, Characterizations and biological efficiencies
Queries 1: Authors should pay attention to the use of capital letters in the title please follow the template of the journal.
Author reply: As per your suggestion carried out
Queries 2: The authors are requested to use new references in the manuscript and especially in the introduction.
Author reply: As per your suggestion carried out
Queries 3: In the abstract as well as in the introduction, please quote the full name (nanoparticles) in the text before citing them NP.
Author reply: As per your suggestion carried out
Queries 4: Introduction: line 54 : The NPs exhibit great medicinal applications in targeted drug administration, (18) wound healing and bioimaging: the number 18??
Author reply: (18) - Typographical error has been removed
Queries 5: Before line 49, it was better to cite some works on the techniques applied especially for the production of ZnO-NPs.
Author reply: As per your suggestion included in the revised manuscript.
Queries 6: (C2H3O2)2.2H2O), Please write the exact formulas with indices
Author reply: As per your suggestion carried out
Queries 7: DMEM medium: Please give the full name of this abbreviation.
Author reply: DMEM (Dulbecco's Modified Eagle Medium) the abbreviation was included in the revised manuscript.
Queries 8: Line 200-203: please review the position of these sentences.
Author reply: As per your suggestion carried out
Queries 9: Figure 5: capitals in the y-axis.
Author reply: As per your suggestion carried out
Queries 10: Figure 7 is illegible please redo it.
Author reply: As per your suggestion carried out
Queries 11: In the conclusion, please add a section on the perspectives that can be drawn from this work, especially on an industrial scale.
Author reply: As per your suggestion carried out
