Nutraceuticals Obtained by SFE-CO₂ from Cladodes of Two Opuntia ficus-indica (L.) Mill Wild in Calabria

Round 1

Reviewer 1 Report

Reviewers' comments:

Manuscript number: applsci-1051736

Title: Nutraceuticals obtained by SFE-CO2 from cladodes of two Opuntia ficus-indica (L.) Mill., wild in Calabria.

 

Comments: 

The manuscript reported on Nutraceuticals obtained by SFE-CO2 from cladodes of two Opuntia ficus-indica (L.) Mill., wild in Calabria. The manuscript needs a detailed editing. It cannot be recommended for publication in the present form. I hope the following points would be helpful for the authors.

 

- In the Abstract: the authors need to improve with more specific short results and conclusions, i.e. academic novelty or technical advantages.

- The introduction section should be improved; more related papers must be discussed and superiority, novelty, critical improvement in this study must be clarified.

- Check line number - 58.

- Check line number - 86.

- Please provides the references for all equations and formula.

- Figure 4, 5 and 6, not clear make clear.

- Figure 7. Chromatogram resulting from the analysis of the extract by SFE-CO2 of OFI s.l. dried to 30 % and added 20 % of Diatomee Sand. – Not clear make clear.

- Line number – 318, SFE-CO2 to SFE-CO₂

- Several faults: are added or missing spaces between words: see manuscript file.

- Conclusion should be concise.

- References: there are recent references in 2019 and 2020 treating the same subject, you can use and make all references in same format for volume number, page numbers and journal name, because it is difficult to searching and reading.

 

So that I recommended this manuscript to major revision and for future process.

 

Author Response

Reviewer 1 suggestions and answers

 

- In the Abstract: the authors need to improve with more specific short results and conclusions, i.e. academic novelty or technical advantages.

We want to thank the reviewer, thanks to his suggestion we tried to improve the abstract

- The introduction section should be improved; more related papers must be discussed and superiority, novelty, critical improvement in this study must be clarified.

According to the reviewer, we improved the introduction

- Check line number - 58.

According to the reviewer, line 58 was checked

- Check line number - 86.

Line 86 was checked

- Please provides the references for all equations and formula.

We say thanks to the reviewer and according to him, we adjusted the equations.

- Figure 4, 5 and 6, not clear make clear.

We tried to make clearer the figures by colouring the histograms.

- Figure 7. Chromatogram resulting from the analysis of the extract by SFE-CO2 of OFI s.l. dried to 30 % and added 20 % of Diatomee Sand. – Not clear make clear.

Thanks for the suggestion, we agree with the reviewer and we have improved the chromatogram.

- Line number – 318, SFE-CO2 to SFE-CO₂

Line 318 was adjusted.

- Several faults: are added or missing spaces between words: see manuscript file.

We say thanks to the reviewer and we checked the manuscript.

- Conclusion should be concise.

Conclusions have been shortened following suggestions

- References: there are recent references in 2019 and 2020 treating the same subject, you can use and make all references in the same format for volume number, page numbers and journal name, because it is difficult to searching and reading.

Thanks to the reviewer recent references were added and the bibliography was adjusted.

 

 

Reviewer 2 Report

In the present study authors compared an innovative and green method to a conventional one in the final aim of maximizing yields and selectivity of polyphenolics compounds from fresh cactus pear cladodes, a highly complex matrix, which present a high health benefit potential.

It contributes to reflect on the selection of the extraction method which highly impact extract yield, composition and activity and show that green technologies (Ultrasound, Microwave, Enzyme assisted one) can be highly useful to avoid the use of organic solvent, which is currently at the heart of the concern in an environmentally point of view.

The manuscript is moderately well written, results are appropriately presented but need to be more discussed and supporting data are well presented.

This is a highly interesting and original work which is, currently, not sufficiently clear and some points need to be clarified before publication.

 

General remarks – Strength and weakness

This research article is really highly interesting and well pointed out the current reflection on environmentally friendly techniques to avoid the use of organic solvents while reducing extraction time and temperature.

Abstract, Introduction and Conclusion are clear and well written.

Working on a fresh product, is really interesting in an environmental point of view as drying is highly energetic consuming step.

 

However, to be more impacting, authors need to check spelling and punctation and some sentences need to be clarified and write in a “well English”.

Moreover, there is some lack of information in the material and methods part and concerning the results and discussion section, the authors are invited to discuss a little bit more some results (as explain in specific comments) and compare or support their explanation by literature.

 

Specific comments

• Introduction

L58 and 60 – there is “)” in excess

L63 - there is “(” in excess

L101 – I’ll propose “conventionally used techniques to obtain…”

 

• Materials and methods

L169 – These analyses were made only one time? Or in triplicate?

L175 – filtered on which filter type (porosity, material)

L181 – On which samples, those presented on figure 3?, with the previous preparation indicating in table 1

L195-198 – the sentence is unclear, I’m not sure to well understood what you do and in which order. Please clarify it.

 

• Results and discussion

L216 – “from” instead of “by”

L220-221 – Have you an explanation to the saccharide difference? Some references which show the same trend?

L238 – higher than which samples? Please, be a little bit more precise.

You compared dried and fresh materials, have you considered water content to compare the value?

L251-257 – Sentences are unclear and need some more precision with value and comparison with literature if possible. For example, why narcissin is more present within cult.AF?

L264-266 – please review sentence, which can be simplify.

L273-275 – this sentence necessitates some explanation on potential hypothesis of why a lower yield has been obtained by SFE, with some references showing the same results or not.

 

• Conclusion

L317 – This can be also added in the results and discussion part with some literature references

L325 – “changing” instead of “chancing”

Comments for author File: Comments.pdf

Author Response

Reviewer 2 suggestions and answers

 

General remarks – Strength and weakness

This research article is really highly interesting and well pointed out the current reflection on environmentally friendly techniques to avoid the use of organic solvents while reducing extraction time and temperature.

Abstract, Introduction and Conclusion are clear and well written.

Working on a fresh product, is really interesting in an environmental point of view as drying is highly energetic consuming step.

 

However, to be more impacting, authors need to check spelling and punctation and some sentences need to be clarified and write in a “well English”.

Moreover, there is some lack of information in the material and methods part and concerning the results and discussion section, the authors are invited to discuss a little bit more some results (as explain in specific comments) and compare or support their explanation by literature.

 

Specific comments

• Introduction

L58 and 60 – there is “)” in excess

the parenthesis has been removed

L63 - there is “(” in excess

the parenthesis has been removed

L101 – I’ll propose “conventionally used techniques to obtain…”

We say thanks to the reviewer and according to him, we adjusted the phrase.

 

• Materials and methods

L169 – These analyses were made only one time? Or in triplicate?

The analyses were repeated in triplicate. A phrase has been added.

L175 – filtered on which filter type (porosity, material)

The mixture was filtered in synthetic cloth. The text was adjusted (line 177).

L181 – On which samples, those presented on figure 3?, with the previous preparation indicating in table 1

The samples reported in Figure 3 are freshly homogenized of OFI cult and s.l. and were used to measure pH, humidity and initial water activity. There is not correspondence with samples in table 1, which are used for extraction.

To be more clear we added “fresh samples of..” in the legend of Figure 3 and the text.

L195-198 – the sentence is unclear, I’m not sure to well understood what you do and in which order. Please clarify it.

Thanks to the reviewer, we have tried to write in a more clear way the sentence.

• Results and discussion

L216 – “from” instead of “by”

The L 216 was adjusted.

L220-221 – Have you an explanation to the saccharide difference? Some references which show the same trend?

Thanks for the question. The difference in composition and then in saccharide generally depends on some factors such as the variety and age of the plant, soil, and climate. We have added a phrase in the text to explain.

 

L238 – higher than which samples? Please, be a little bit more precise.

You compared dried and fresh materials, have you considered water content to compare the value?

The sentence was adjusted to be more precise. In the sentence we compared two samples fresh, the only difference is in the maturation period. We have specified in the sentence and now I hope is more clear.

L251-257 – Sentences are unclear and need some more precision with value and comparison with literature if possible. For example, why narcissin is more present within cult.AF?

We thank the reviewer and have tried to make the sentence clearer.

L264-266 – please review sentence, which can be simplify.

According to the reviewer, the sentence was modified.

L273-275 – this sentence necessitates some explanation on potential hypothesis of why a lower yield has been obtained by SFE, with some references showing the same results or not.

We say thank to the reviewer and on the light of the question, we tried to adjust and explain the L273-275.

• Conclusion

L317 – This can be also added in the results and discussion part with some literature references

The suggestion was followed.

L325 – “changing” instead of “chancing”

The word was changed.

 

 

Round 2

Reviewer 1 Report

Reviewers' comments:

The manuscript has been modified to my satisfaction. There are some minor errors but this can be corrected during proofreading.

- Line number 110: CO2 to CO₂

- Line number 313: SFE-CO2 to SFE-CO₂

- Line number 315 and 317: CO2 to CO₂ and SFE-CO2 to SFE-CO₂

 

So that I recommended this manuscript accept for publication in Applied Sciences.

Author Response

 -Line number 110: CO2 to CO₂

Line 110 was checked

- Line number 313: SFE-CO2 to SFE-CO₂

Line 313 was checked

Line number 315 and 317: CO2 to CO₂ and SFE-CO2 to SFE-CO₂

Lines 315 and 317 were checked