Maclura tinctoria Extracts: In Vitro Antibacterial Activity against Aeromonas hydrophila and Sedative Effect in Rhamdia quelen
, Luisa Barichello Barbosa 2, Bibiana Petri da Silveira 3, Guerino Bandeira Junior 1, Lenise de Lima Silva 1, Amanda Gindri 4, Rodrigo Coldebella 5, Cristiane Pedrazzi 5, Agueda Palmira Castagna de Vargas 3, Bernardo Baldisserotto 1 and Berta Maria Heinzmann 1,2,*
Round 1
Reviewer 1 Report
The manuscript entitled “Maclura tinctoria Extracts: in vitro Antibacterial Activity against Aeromonas hydrophila and Sedative Effect in Rhamdia quelen" (ID: fishes-1276368) submitted by Luana da Costa Pires et al. The manuscript was well planed, executed and organized with covered a lot of informative data towards the antimicrobial activity against Aeromonas hydrophila. I appreciate the author team, because they chose the valuable research in the field of herbals. Herbals are a nutraceuticals, nowadays they are highly influence in aquaculture industry. Herbal products have been reported to promote various activities like antistress, growth promotion, appetite stimulation, tonic and immunostimulation, and to have aphrodisiac and antimicrobial properties in finfish and shrimp culture due to the active principles such as alkaloids, flavanoids, pigments, phenolics, terpenoids, steroids and essential oils. The MS is well planned, executed and covered a valuable analysis. I recommend this manuscript for publication after few technical errors.
Specific comments
Antimicrobial may change to Antibacterial activity in materials and methods section
Scientific names must presented in italic styles
Author Response
Dear reviewer,
The manuscript has been altered according to your suggestions. The authors would like to thank the reviewers for the time spent in evaluating the study and are open to further comments and suggestions.
Best wishes,
The authors.
- First comment:
"Antimicrobial may change to Antibacterial activity in materials and methods section"
Your request has been accepted. See revised version of the manuscript.
- Second comment:
"Scientific names must presented in italic styles"
Your request was granted. We have carefully revised the text and the revised version has all scientific names in italics.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The paper presents a work on the antibacterial activity as well as the sedative effects of the extracts of a tree (Maclura tinctoria), basically due to phenolic compounds, a fact that already is well know.
The work presents interesting results but a number of questions should be solved before to be accepted.
- The main question is about the concentration of extracts: are not too high to be of practical use? Even the MIC of 400 ug/ml would be possible to attain in a treatment on the fish? Some comments are necessary.
- Also, some paragraphs about the antibacterial activity concentration and the interaction with the sedative activity and the possible combined effects should be included.
Abstract
- LIne 22- the sentence indicates "fish pathogens" but only three strains of Aeromonas hydrophila and one of A. veronii were tested. Maybe should be better to state against Aeromonas strains.
- Line 23.- The writting needs some Improvement (“central depressant effect “?)
- Line 27.- Polyphenolic compounds with antimicrobial activity and central depressant effects … may be… “and sedative effects”
Results
- Heading 2.2: Explain what means strains 13 (A. hydrophila),…Strains 18 and 169/07 not appear in the text.
- Line 97.- Should say intermediate not intermediary.
Fig 1: Explanation text: Recovery time (in seconds?). All the figure needs a better text within the explanation.
Materials and Methods.
- In the section 4.7.2, there are a confusing score for sedation stages: In table 6, Stage S2 light sedation and S5 death, but in the text, lines 353-365, the lower score, the deeper stages of sedation !!!!
Author Response
Second reviewer:
The paper presents a work on the antibacterial activity as well as the sedative effects of the extracts of a tree (Maclura tinctoria), basically due to phenolic compounds, a fact that already is well know.
The work presents interesting results but a number of questions should be solved before to be accepted.
- The main question is about the concentration of extracts: are not too high to be of practical use? Even the MIC of 400 ug/ml would be possible to attain in a treatment on the fish? Some comments are necessary.
This question was complemented in the discussion of the revised version of the manuscript. See p. 7 of the new version of the manuscript.
- Also, some paragraphs about the antibacterial activity concentration and the interaction with the sedative activity and the possible combined effects should be included.
This question was also adressed in the discussion of the second version of the manuscript. See p. 7 and 8 of the revised manuscript.
Abstract
- LIne 22- the sentence indicates "fish pathogens" but only three strains of Aeromonas hydrophila and one of A. veronii were tested. Maybe should be better to state against Aeromonas strains.
As requested, the we replaced “fish patogens” by “Aeromonas strains” in the abstract.
- Line 23.- The writting needs some Improvement (“central depressant effect “?)
The abstract was altered as requested, and “central depressant effect “was replaced by “sedative effect”
- Line 27.- Polyphenolic compounds with antimicrobial activity and central depressant effects … may be… “and sedative effects”
OK, the suggestion was accepted.
- Heading 2.2: Explain what means strains 13 ( hydrophila),…Strains 18 and 169/07 not appear in the text.
Bacterial strains were isolated and identified in a previous work from our research group. Detailed information has been added in the experimental section. See p. 9 of the revised manuscript.
- Line 97.- Should say intermediate not intermediary.
The suggestion was accepted.
Fig 1: Explanation text: Recovery time (in seconds?). All the figure needs a better text within the explanation.
As requested, the title of figures 1 and 2 has been improved. See revised manuscript, at p. 5 and 6.
Materials and Methods.
- In the section 4.7.2, there are a confusing score for sedation stages: In table 6, Stage S2 light sedation and S5 death, but in the text, lines 353-365, the lower score, the deeper stages of sedation !!!!
Table 6 presents fish sedation and anesthesia stages, considered for evaluation of central nervous system depressant activity evaluation (see section 4.7.1). However, section 4.7.2 describes the behaviour scores of prolonged exposure experiments. These tests were performed to analyze the possible side effects of the extracts for 24 hours. Additionally, we only used the sedative concentrations selected after the first experiment in the long exposure test.
For better understanding, two sentences were added in section 4.7.1 to explain the experiments aim: “The long exposure and survival tests were performed to analyze the extracts possible side effects for 24 h. For this test, the best sedative concentrations were selected after the first experiment (section 4.7.1).”
See new version of the manuscript.
