Three-Dimensional Printing of Biomass–Fungi Biocomposite Materials: The Effects of Mixing and Printing Parameters on Fungal Growth

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The article "3D Printing of Biomass-Fungi Biocomposite Materials" examines the effects of various parameters on fungal growth in biomass-fungi biocomposite materials used for 3D printing. In particular, the authors analyze the effects of mixing parameters (mixing time and mixing mode) on fungal growth in the mixtures, as well as the effects of printing parameters (printing speed and extrusion pressure) on fungal growth in the printed samples.

The research provides important insights into the conditions under which the fungi can grow optimally in the biomass-fungi biocomposites and examines how the 3D printing process affects fungal growth.

The results of the study show that a longer mixing time leads to a significant increase in fungal growth, while the mixing mode has less effect on growth. In addition, the 3D printing process was found to reduce fungal growth in the printed samples, with high printing speeds and extrusion pressures leading to greater reductions.

The research provides valuable insights for the production of biomass-fungal biocomposite materials and their use in 3D printing. It shows how the process parameters can be optimized to achieve the desired properties of the printed products.

Overall, the article is well-structured and presents clear results. The authors have conducted the study diligently and have appropriately presented their findings. One noteworthy point to consider is whether the quantity evaluation of growth is the sole quality parameter or if there are other factors involved. I recommend adding a detailed supplementary note to the article to assist readers in comprehending and verifying your results more effectively.

Author Response

Howdy,

The authors have made appropriate changes according to the reviewer's comments.

Regards,

Al Mazedur Rahman

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

-3D printing is a general term. Please specify what type of additive manufacturing/3D printing process is used in the abstract and early in the Introduction section.

-Table 1 includes relevant literature. It would be more helpful to indicate what findings/conclusions are from these studies.

-L100, the objectives and the scientific question to be investigated could be better articulated.

-Increase the font size in Fig. 1. The resolution, as shown, is too low.

-Consider moving Fig. 1 to the method section and explain the process more thoroughly.

-Specify the form of the biomass material (e.g., average size, length, diameter, etc.)

-L115, Specify the temperature/pressure/duration of the autoclave procedure.

-L121, provide some measurements of “small pieces.” How did the authors ensure consistency?

-L138, it’s not very clear if the screw extruder spin or not? If so, specify the rotational speed. Provide the channel size/angle of the screw extruder.

-L151, how many images were counted for each sample? How uniform are the colonies spreading over the plate?

-L180, describe the geometry of the samples that were printed. A brief description of the slicing/infill pattern would be helpful, too.

-The authors need to have a better understanding of the statistical analysis. L200-L206 don’t tell much. Also, revisions are needed for how to report significance level later in the text.

-Sec. 3.1, suggest moving the reporting of the raw data up (Figs. 6-8) before reporting the summary table 5.

-L234, Is it still statistically significant? what is the significance level of 0.279?

-Fig. 8 & L347, is there an interaction effect or not? Or is the difference due to mixing time?

-Report the average temperature reading of all test conditions.

-L268, is there a significant difference? 0.414? Also in L279.

-Show some images of the printed product.

-Overall, the results are not sufficiently strong to support the conclusions, except for the mixing time.

Comments on the Quality of English Language

Some minor corrections are needed such as missing articles.

Author Response

Howdy,

The authors have made appropriate changes according to the reviewer's comments.

Regards,

Al Mazedur Rahman

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have presented an extension to their published work that is viewed through the lens of microbiology. The manuscript requires revisions to avoid duplicating previously published work, specifically about the images and techniques, and to focus more on microbiology aspects.

1. The literature in the current manuscript needs extensive revision rather than explaining the stages of 3D printing, as these have already been explained thoroughly in the authors' previously published work on the same topic. Instead, the manuscript focuses on fungal growth and the effects of printing. To better identify the research gap, it would be beneficial for the authors to briefly discuss the literature on Fletcher et al. (as mentioned in line 237) and the printing effects described in citations 37, 38, and 39.

2. It would be beneficial if the authors included 3D-printed models to illustrate fungal growth and highlight any differences.

3. In their study, the authors stressed the significance of printing parameters. However, the methodology lacks clarity regarding how the analysis of these parameters was conducted. The study does not specify whether the analysis was based on strand analysis, filament collapse, or printing accuracy. It is evident that modifications in printing speed and extrusion can lead to variations in printability. Hence, providing a more detailed analysis of printing accuracy or printability would be helpful. 

3. The authors mentioned the relevance of extrusion pressure and shear stress in line 272. It is requested to provide a rheological analysis of materials after different mixing time or mixing mode. 

4. Including more detailed fluorescence or SEM images would enhance the current studies. 

Please look at the PDF for other general comments. 

Comments for author File: Comments.pdf

Author Response

Howdy,

The authors have made appropriate changes according to the reviewer's comments.

Regards,

Al Mazedur Rahman

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have addressed most provided comments. However, revision is still needed regarding the results of statistical analysis. The authors should determine a significance level (usually p-value <0.05) in Sec. 2.6. This pre-determined significance level should be used for all results. It's not typical to vary the significance levels (0.414, 0.251. 0.203....) for different results. Their type-I error is too high.

In L213, Ref 31 might not be the best reference for the significance level. 

Comments on the Quality of English Language

Minor editing check. Some missing articles.

Author Response

The review has been submitted.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The amended draft is acceptable for publication

Author Response

Thank you for accepting the manuscript.

Author Response File: Author Response.docx

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

L263-L270, the two paragraphs seem a bit redundant. Otherwise, the paper has improved.

Author Response

Howdy,

The authors have reviewed the comments and updated the manuscript.

Author Response File: Author Response.docx