Third Generation Lactic Acid Production by Lactobacillus pentosus from the Macroalgae Kappaphycus alvarezii Hydrolysates

Round 1

Reviewer 1 Report

I have reviewed the paper "3G-Lactic Acid Production by Lactobacillus pentosus from the 2 Macroalgae Kappaphycus alvarezii Hydrolysates". The study is interesting and fits with journal scope. However, the following specific points should be addressed before acceptance. 

Abstract

Mention the fermentation conditions followed in the bioreactor? 

Keywords: Avoid the words used in the title

Introduction

What is the cost economics of K. alvarezii ? Is it cost effective as compared to other agri-biomass? 

Write/Explain a basis of selection of suitable culture

Write the results of similar studies?

Explain the novelty of this study?

Materials and methods

Use the standard reference for the methods followed?

Use the reference style/format according to the journal style?

vacuum filtering? Mention the pressure level/vacuum level  

Mention the size of paper filter?

What is the statistical method followed for ANOVA?

Results and discussion

What is the criteria followed for the selection of Ratio of algal mass/acid solution?

Figure 2. Add the Standard error or standard deviation/error bar value 

Table 2 :  Add the Standard error or standard deviation/error bar value. The same should be followed for all the figures and tables.

The effect of fermentation conditions on the rate of fermentation should be explained. 

References: Format according to journal style

Update the old references. Replace with recent publications  

 

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

This manuscript described on lactic acid production by Lactobacillus pentosus from macroalgae hydrolysates.

 The mainstream of research on lactic acid production by lactic acid bacteria has been based on carbohydrates produced on land. Lactic acid production from carbohydrates from water environments is considered to be a very unique and valuable endeavor.

 Major points:

1.      Please describe impact of this study at the last paragraph of “Introduction”.

2.      Please discuss on the most important point of this study and evaluate the obtained result considering of the background studies at first paragraph of “Discussion”

3.      Please present the yield of the object material in each step for treatment for K. avarezii.

Please present data for understanding of carrageenan content in the algae and yield of galactose from carrageenan.

4.      Please describe procedure form measurement of HMF.

5.      Table 1: Normally, cellulose does not contain galactose.

6.      Table 2: Is it sure that K. avarezii hydrolysates contain lactic acid.

7.      Table 3: Normally, the growth of lactic acid bacteria is inhibited by the accumulation of lactic acid. Therefore, the acid should be neutralization is necessary for high production of lactic acid. This reviewer wanders that it is difficult to adjust pH in 100 ml serum flask. If the authors did not neutralize pH, please describe the final pH of each medium.

8.      Table 4: This results of “acclimated” exhibited lower lactic acid productivity than those in Table 3. Are there any reasons for the difference?

9.      Please present values presented in Table 3 for4 Figure 3 results.

10.  Table 6: Please explain “Yield”. Is it based on the dry biomass?

Minor points:

1.      Is lactic acid L-lactic acid?

2.      “3G” in the title and Abstract should not be abbreviated.

3.      L14: Please make clearer for “treated” and “untreated”. Is this mean detoxify or not?

4.      L340 & 344: Bacterial scientific name should be italics.

5.      L345: Algal scientific name should be italics.

6.      L352 & L353: “sp” should not be italics.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The manuscript described on lactic acid production by Lactobacillus pentosus from macroalgae hydrolysates has been revised.

 This reviewer found that the authors sincerely responded reviewer’s comments.

1)   RPM → rpm (throughout the manuscript)

2)   Please describe ingredients of MRS medium.

3)   Table 4 (formerly Table 3): It is difficult to understand the reason for the different galactose content between two detoxified 30% (w/v). Please make understandable in present of hydrolysate each batch.

4)   This reviewer　thought that the added last line (detoxified 30% [w/v]) in Table 4 batch used the 100% hydrolysate. However, the galactose content is different from the description in Table 3.

Author Response

Please see the attachment.

Author Response File: Author Response.docx