Bioflocculant Producing Bacillus megaterium from Poultry Slaughterhouse Wastewater: Elucidation of Flocculation Efficacy and Mechanism

Round 1

Reviewer 1 Report

The manuscript examines bioflocculants from microorganisms from poultry slaughterhouse wastewater. Flocculation is one of standard methods for water purification. So, instead of widely used flocculants, finding a new flocculant might be useful from the view of environmental issue. My comments are as follows.

Readers might be confused what D2 and RSW are. Abstract is handled independently. So, it is better to avoid using abbreviations without definition.

L and l are used for litter. I guess L is better.

Lines 23-27 should be written with shortened sentences.

What about the possibility of sweep flocculation performance of developed flocculant? Sweep aggregations of imogolite clay and poly-γ-glutamic acid support the effectiveness. This possibility should be discussed.

The authors should a space between number and unit.

Figure 2: dpi should be higher.

Line 332: mV should be added after the values of zeta potential.

What kind of equation was used to extract zeta potential from electrophoretic mobility measured by zeta sizer? Even for model hydrophobic polystyrene particles, hydrodynamic slip is concerned. Also, double layer relaxation works during electrophoresis. These points should be addressed.

Author Response

Dear Reviewer,

We want to express our heartfelt gratitude for your thorough review of our manuscript,  Your insightful feedback has significantly improved the quality of our research. Attached are the revised manuscript and our responses to your comments, which we believe have enhanced the clarity and robustness of our work. Your expertise and dedication to scholarly excellence are truly commendable, and we sincerely appreciate your valuable contributions to our manuscript. Please feel free to contact us if you have any further queries.

Warm regards,

Prof. Basitere

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript is well-structured and written. In the Introduction section please briefly report other studies where Bacillus species were identified as potential flocculants. Please use a separate paragraph for the aim of the study. Line 133 please check the size of the font. Authors state that “This process is affected by various factors, including nutrient availability and composition, physicochemical parameters, and culture conditions’’. Please provide information on the poultry slaughterhouse wastewater, regarding its physicochemical characteristics. Have the authors tested Bacillus megaterium under real conditions and not only in an isolated environment to assess the behavior of this particular bacillus?

Author Response

Dear Reviewer,

We want to express our heartfelt gratitude for your thorough review of our manuscript,  Your insightful feedback has significantly improved the quality of our research. Attached are the revised manuscript and our responses to your comments, which we believe have enhanced the clarity and robustness of our work. Your expertise and dedication to scholarly excellence are truly commendable, and we sincerely appreciate your valuable contributions to our manuscript. Please feel free to contact us if you have any further queries.

Warm regards,

Prof. Basitere

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

"The zeta potential values reported were obtained directly from the instrument measurement and were not calculated manually. A Zetasizer Nano ZS (Malvern Panalytical Ltd, Malvern, United Kingdom) was used." indicates that  the authors are unfamilar with the relationship between zeta potential and electrophoretic mobility. The authors should learn more about this reltionship and then properly answer my question.

Author Response

Dear reviewer

Thank you very much for taking the time to read and review our paper. Your feedback is greatly appreciated and will undoubtedly contribute to improving the quality of our research. We value your insights and look forward to addressing any comments or suggestions you may have provided.

Kind regards

A/Prof Moses Basitere

Author Response File: Author Response.pdf