Antimicrobial and Herbicidal Secondary Metabolites from Insect-Associated Fungus Leptosphaeria sp. FZN28 in Mecopoda elongata

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This is a very interesting paper and work that should be published. Biocontrols are becoming very popular and having various options are great. While the research is good, the framing of the project needs to be addressed. It reads like a plant pathology paper, but is more of an IPM paper. I think reframing the introduction to be more IPM focused will help the studies with weeds seem less random in the manuscript. The other question I had from the results section is that compound 6 is mentioned but nowhere in the materials and methods. This should be addressed. Overall, good study just needs some editorial changes.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript entitled “Antimicrobial and herbicidal secondary metabolites from en-2 dophyte Leptosphaeria sp. FZN28 in Mecopoda elongate” describes fungicide and herbicidal activities of secondary metabolites isolated from the endophytic fungus Leptosphaeria sp. FZN28. The work included structural characterization by spectroscopic analyses, in vitro and ex vivo antimicrobial assays, observations by electronic microscopy and in vivo herbicidal studies with two weeds.  Authors concluded that compounds 1 and 2 could have potential as biopesticides. In my opinion, more details of experimental procedures are necessary to consider the publication of the manuscript.

1) Line 36. The concept of endophytes should be revised, as it refers to microorganisms that reside in vegetable tissues (endo-phyto) rather than insects and microbes, perhaps “endosymbiont” would be more appropriate.

2) Line 40. Indicate that Leptosphaeria species are fungi.

3) Line 52-55. “Chemical control has been widely 52 adopted for crop production to manage plant diseases and weeds and the growing de-53 mand for sustainable agrochemicals with eco-friendly profiles has led to increased interest 54 in secondary metabolites from microbes”. Include references that supports author`s statement.

4) Line 71. “Fungal” strains.

5) Line 81. In plant material include information concerning to cole leaves.

6) Line 84. “Fermentation, extraction and characterization” of secondary metabolites.

 7) Line 90. Detail how much volume of ethyl acetate was used to obtain the crude extract, and how the solvent was evaporated.

8) Line 92. MeOH: Does it correspond to methanol? Name it correctly.

9) Line 105. Include a title more suitable to the described experimental procedure, such as “Antifungal activity in vitro”.

10) Line 118. Detail how much volume of compounds 1 and 2 was used in sprays, as well as the size of agar pieces of S. sclerotiorum. Deatil volume and concentration of Tebocunazole and how it was applied in cole leaves.

11) Line 122. More details about greenhouse assays should be included, such as genera and species of plants, quantity, age/state of development, pot volume, substrate, etc.

12) Line 246-247. “… zoospore germination was significantly delayed by the two compounds”. There were not statistical analyses that support significant effects on zoospore germination.  

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript “Antimicrobial and herbicidal secondary metabolites from endophyte Leptosphaeria sp. FZN28 in Mecopoda elongata” describes the isolation and identification of seven known secondary metabolites from the endophytic fungus Leptosphaeria sp.. The manuscript also describes the evaluation of antimicrobial and herbicidal activities. This research is important for the development of a sustainable agriculture, which is global challenge.

The topic is relevant to different areas, such as, biotechnology, natural products, and biological control, as it addresses the search for natural compounds that can replace synthetic and toxic pesticides, which are harmful to the environment and to life.

The article offers new experimental data on the isolation and biological activity of the compounds described in the manuscript.

The conclusions are consistent with experimental observations. However, further studies are needed before the isolated and evaluated substances can be used in agriculture. I understood that the manuscript suggests a possible application of these substances in agriculture. The authors wrote in conclusion: " these findings enrich a potent source for the production of agrochemicals to ensure food security and highlight their potential as leading compounds for the development of new biopesticides." 

The references are appropriate.

 

Comments:

• In the discussions, the authors repeated the results (presented in 3 out of 4 paragraphs). A critical discussion of the results regarding the current realities and the challenges faced in agriculture against pests and diseases should have been included. Authors should revise the discussion for emphasizing agrochemical applications and limitations
• the methodology used is adequate. Perhaps the authors could have presented a better explanation/description about MEV and MET.
• Some minor comments have been added to the attached file.

In my opion, the manuscript should be accepted after minor revision. The authors should improve the discussions and make some corrections pointed out in the text (attached file).

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf