Chemical Composition, Structural Properties, and Bioactivity of Carrageenan from Field-Cultivated Betaphycus gelatinus

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The article titled "Chemical Composition, Structural Properties, and Bioactivity of Carrageenan from Field Cultivated of Betaphycus gelatinus" written by Tran van Huynh et al. describe thoroughly  the process of analyzing the structure and bioactive properties of carrageenan in combination with identification of optimal harvest period for polysaccharide with best properties and bioactivity .

This study provides a comprehensive analysis of the seasonal biomass dynamics, chemical composition, structural properties of carrageenan obtained from field-cultivated B. gelatinus in Ninh Thuan, Vietnam.

The biomass formation protocol is thoroughly described as well as sample preparation for each analytical method. The results of experiments performed with those methods are consistent and based on previous cited findings. I only do not understand why e.g. FTIR and NMR spectroscopy data are not presented as a function of time/ season of a harvest period? The intensity of peaks in the IR spectrum may very upon various proportions of kappa to beta carrageenan content. Maybe this could be an idea for further research?

All in all, the article is very interesting, written with good composition and english. The results show that open-sea cultivation achieves carrageenan quality comparable to wild/ natural samples and retains a stable structural profile, essential for its bioactive properties.

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

While this study provides a comprehensive overview of B. gelatinus cultivation and highlights its potential applications, it has a few limitations.

The research is geographically confined to the central coast of Vietnam, potentially limiting the generalizability of its findings to other regions with varying environmental conditions. This narrow focus may restrict the applicability of seasonal harvesting schedules in regions where temperature and light exposure differ significantly.

While the bioactivity of pyruvylated carrageenan is noted, more detailed investigations into the specific mechanisms driving its antibacterial and antioxidant properties are needed. This would provide a stronger foundation for industrial applications, especially if the carrageenan's efficacy varies across different bacterial strains or in diverse food preservation scenarios.

 

Author Response

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Reviewer 3 Report

Comments and Suggestions for Authors

Journal: Processes

Manuscript ID: processes-3326909

Manuscript Type: Article

Title: Chemical Composition, Structural Properties, and Bioactivity of Carrageenan from Field Cultivated of Betaphycus gelatinus

In this interesting research, the authors investigated seasonal biomass variations in a red alga Betaphycus gelatinus, performed a comprehensive analysis of its chemical composition and structural properties, and assessed the bioactivity of its carrageenan. The manuscript is well-written and correctly conceptualized. In addition, the conducted research has scientific merit, regarding carrageenan derived from B. gelatinus and its promising applications as a preservative and antioxidant agent in health and food industries. 

However, some minor issues should be addressed:

1          1)  Page 3, Lines 128 and 129: This sentence is confusing. Please rephrase it.

2          2) Page 4, Lines 159: Why do not use the unit μL instead of mm³?

3)   Page 4, Lines 166: Replace (²H₂O) with D₂O.

4)    Within Figure 1, replace commas with periods in decimal numbers.

5)  Why the bacterium L. monocytogenes was chosen for determining antibacterial activity? If possible, consider the testing of antibacterial activity on some Gram-negative bacteria, which is also important in food preservation and safety. Additionally, it would be beneficial to consider testing the antibacterial activity on some standard antibiotics to compare the effect.

6) Within the Discussion section, discuss the results of antibacterial activity in light of the results of similar studies to get a clearer picture of the results' significance.

7) Within the Discussion section, discuss the results of antioxidant capacity in light of the results of similar studies.

Comments for author File: Comments.pdf

Author Response

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