Removal of Pb (II) from Aqueous Solution by a Pectin-Producing Alga, Penium margaritaceum, Immobilized on Filter Paper

Round 1

Reviewer 1 Report

In the present manuscript, the authors investigated the toxic Pb(II) removal using bio filter paper to safeguard public health. The authors presented a good overview of the topic even if a lot has been already reported in previous articles, which must be included in this manuscript. By citing previous articles, the authors can define how the present review differs from others and what is the need to still review harmless treatment pathways and specific applications, while many articles are already published. The comments are given below.

-The language of the manuscript is very pitiful, due to which several times it is hard to understand what the authors exactly want to tell. Hence, the language must be improved by a professional service.

-The Figure’s quality needs to be improved in the revision stage.

-References: There are many references that are not adjacent to this study. The authors need to take notes in the revision stage and cite relevant references including high-impact journals to make the manuscript to a broad range of readers.

-Abstract: This section needs to be improved by presenting novel findings such as investigating the effect of the diverse pollutants, and the main experimental works in the revision stage.

-Introduction: Composite materials are growing attention for diverse pollutants removal based on their specific functionality and surface area as reported by Awual group according to ScienceDirect. The authors need to indicate such points for a broad range of readers. Moreover, the authors need to cite high-impact articles to make the manuscript high-level. The following specific articles may take be noted in the revision stage of Journal of Environmental Chemical Engineering 7 (2019) 103124; Microchemical Journal 160 (2021) 105765.

-Scientists considered the removal technology based on selectivity, sensitivity, cost-effectiveness, and so on. The authors need to indicate such a point in the revised manuscript.

-The materials characterization is not accurate. The main morphology needs to be added instead and then compared with reported materials including Microchemical Journal 161 (2021) 105800.

-Can the present study be effective from the real waste samples? The authors need to write such sentences in the revision stage.

I would like to see the revised manuscript.

Author Response

Thank you very much for your valuable time in reviewing our manuscript. Our responses to your comments are as follows.

> The language of the manuscript is very pitiful, due to which several times it is hard to understand what the authors exactly want to tell. Hence, the language must be improved by a professional service.

English of our manuscript has been carefully edited.

> The Figure’s quality needs to be improved in the revision stage.

Quality of figure 3 and figure 4 has been improved.

> References: There are many references that are not adjacent to this study. The authors need to take notes in the revision stage and cite relevant references including high-impact journals to make the manuscript to a broad range of readers.

Totally six references have been added.

> Abstract: This section needs to be improved by presenting novel findings such as investigating the effect of the diverse pollutants, and the main experimental works in the revision stage.

The abstract has been intensively modified according to your comments.

> Introduction: Composite materials are growing attention for diverse pollutants removal based on their specific functionality and surface area as reported by Awual group according to ScienceDirect. The authors need to indicate such points for a broad range of readers. Moreover, the authors need to cite high-impact articles to make the manuscript high-level. The following specific articles may take be noted in the revision stage of Journal of Environmental Chemical Engineering 7 (2019) 103124; Microchemical Journal 160 (2021) 105765.

The introduction has been modified according to your comments and the two references have been added.

> Scientists considered the removal technology based on selectivity, sensitivity, cost-effectiveness, and so on. The authors need to indicate such a point in the revised manuscript.

Description about cost-effectiveness has been added in Discussion. In the future research, we plan to examine about selectivity and sensitivity.

> The materials characterization is not accurate. The main morphology needs to be added instead and then compared with reported materials including Microchemical Journal 161 (2021) 105800.

An analysis result using FT-IR has been added, and the reference and description related to morphology have been added.

> Can the present study be effective from the real waste samples? The authors need to write such sentences in the revision stage.

In the future research, we plan to perform an experiment using real waste samples. Thank you for your useful suggestions.

Reviewer 2 Report

This is a nice manuscript that describes the lead-binding possibilities of the green alga Penium and its potential significance for lead bioremediation. This is the first report to this reviewer's knowledge that describe the potential of a charophyte green alga for heavy metal removal. There are some flaws in the manuscript including:

1) page 2, lines 48-50: what lower plants or charophytes do not have Golgi bodies? They all do and must in order to produce a cell wall.

2) From a taxonomic standpoint I would describe Penium's taxonomic position in the basal Streptophya or Charophycean Green Algae. The authors should check out recent papers by J. de Vries.

3) Careful editing should be performed. For example, on page 2, line 92, should it be "immobilized algal cells"? On page 4 lines 155 and 161- it should be "cells".

4) On page 7, line 215, perhaps "cell wall layers" should be used instead of "cell surface lamella structure".

Finally, this study could be improved if there was a comparison of cultural conditions and lead uptake. That is, compare uptake at different pHs and do a comparative analysis with other heavy metals including adding mixed heavy metals to the algal assay. The EDS could then be used to provide semi-quantitative information about other heavy ions restricting lead absorption by the cells.

Author Response

Thank you very much for your valuable time in reviewing our manuscript.Our responses to your comments are as follows.

1) page 2, lines 48-50: what lower plants or charophytes do not have Golgi bodies? They all do and must in order to produce a cell wall.

The sentence has been corrected properly.

2) From a taxonomic standpoint I would describe Penium's taxonomic position in the basal Streptophya or Charophycean Green Algae. The authors should check out recent papers by J. de Vries.

“Charophyta” has been replaced with “Streptophyta” and the related reference has been added.

3) Careful editing should be performed. For example, on page 2, line 92, should it be "immobilized algal cells"? On page 4 lines 155 and 161- it should be "cells".

English of our manuscript has been carefully edited.

4) On page 7, line 215, perhaps "cell wall layers" should be used instead of "cell surface lamella structure".

"cell surface lamella structure" has been replaced with "cell wall layers".

> Finally, this study could be improved if there was a comparison of cultural conditions and lead uptake. That is, compare uptake at different pHs and do a comparative analysis with other heavy metals including adding mixed heavy metals to the algal assay. The EDS could then be used to provide semi-quantitative information about other heavy ions restricting lead absorption by the cells.

In the future research, we plan to perform an experiment related to selectivity among heavy metals. Thank you for your useful suggestions.

Round 2

Reviewer 1 Report

The authors revised the manuscript based on the remarks to improve the manuscript for the reader’s understanding. Accept.