Development of Candelilla Wax Oleogels as a Medium of Controlled Release of Phosphorus in an In Vitro Model

Round 1

Reviewer 1 Report

The work entitled: “Development of candelilla wax oleogels as a medium of controlled release of phosphorus in an in vitro digestion model” is interesting, however, the introduction requires significant improvement in terms of content. In my opinion there is a lack of the latest references in this field. Authors should increase introduction thematic scope. There is no detail information, about oleogels and gelator molecules, e.g.: doi:10.3390/agriculture10060211;  https://doi.org/10.1007/s13197-019-04193-8  Detailed comments:

There is a lack, of new literature on the studies of oleogels, in the introduction and in discussion of results.

Introduction should be based only, on the information, from the other scientific papers (works), but not on the authors' analysis. E.g. L.69:“For this reason, our hypothesis is that…”;L.71:To validate this, we proposed to engineer.

L-35-59: „In regions where…………. absorption of another [11].” The Substantiation is too long, it should be shortened.

L.66-67: “An oleogel is a material made by ….. organic solvents, such as vegetable oils [13,14]. and L.75 - :” Such molecular…properties [20–22]” Authors should provide newest  information from other scientific papers (works). Please introduce the newest references.

L.77-80: „that report a melting…materials commercially available).” – Please provide the reference.  

Materials

This paragraph does not describe what kind of samples were tested in the work, only the raw materials has been provided. Please add the table with the study sample’s names.

Please explain, why solutions at 10%, 15% or 20% was prepared?

Tab.1 –all abbreviations should be explained

Regarding Conclusion

The conclusion paragraph, should be made improve too. Summary, should include only conclusions resulting from this work results.

L433-437: „Little has been studied about….”.- Should be deleted.

Author Response

Thank you for your comments and observations. Please find enclosed the responses

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments on applsci-1177042

General comment

This work focuses on the design of bolus formulations based on a CW oleogel, and their evaluation as carriers to deliver phosphorus to ruminants digestive tract using an in vitro model. From my perspective, the main novelty of this research is related to the design of CW oleogels for targeted delivery. Please find my comments below.

Specific comments

Title: Please include the scientific name of candelilla here, in the abstract, and introduction.

Line 24: Two studied model systems?

Lines 42-43: When using ‘on the other hand’, authors should first use ‘on the one hand’ in a previous sentence.

Lines 42-44: Mineral supplements with low bioavailability are normally in a form that is poorly water-soluble or does not efficiently dissolve in the ruminal digestive fluid. Therefore, a good strategy would be to improve/focus on the design of supplements so they are completely absorbed. Another strategy is the one that authors have proposed in this research. Of course, the choice depends on the type of mineral and its toxicity. Please clarify these aspects in the introduction.

Lines 48-49: ‘For example, …’ This sentence is not complete, the verb is lacking.

Line 73: Is it only approved in Mexico? Or somewhere else? If only in Mexico, authors need to specify this.

Line 97: Oleogels were prepared? You cannot develop an oleogel.

Line 97-98: This sentence is not grammatically correct. How can a percentage be heated?

Lines 113: ‘Afterwards, the thermal set was as follows’. This sentence is not grammatically correct.

Method 2.4: A low relative humidity in the room could also contribute to water losses through evaporation. In 10 days of analysis, water evaporation can be significant. How accurate then is this technique to measure liquid release? Could authors prove evaporation losses are not significant?

Method 2.6: Was a mastication step considered in the in vitro digestion method? For solid-like foods, this is a critical step since the integrity of the oleogel will change. This, of course, will also impact the release of phosphorus from the matrix since a larger exposure area will be created.

Method 2.7: It will be quite confusing to the reader if authors use the term digestion for the procedure employed in this section. Please replace the term digestion when referring to this method in the whole manuscript.

Lines 396-408: The determination of phosphorus content in commercial supplements has no relation with the previous results. It would have been interesting that authors also in vitro digested these supplements to compare the release of phosphorus as reference samples. However, this was not done, and presenting phosphorus content of the commercial supplements has no sense at all. I suggest removing this part from the manuscript.

Table 3: I suggest authors present this table in the form of Figure as done in Figure 4. This would allow the comparison of results in both sections 3.3 and 3.4.

Lines 392-394: There are many in vitro digestion models proposed to evaluate the release of nutrients in ruminants. Therefore, this is not a novel aspect of this work. Examples are given below:

• Tamminga, S., & Williams, B. (1998). In vitro techniques as tools to predict nutrient supply in ruminants. BSAP Occasional Publication, 22, 1-11.
• Lopes et al. (2015). Validation of an in vitro model for predicting rumen and total-tract fiber digestibility in dairy cows fed corn silages with different in vitro neutral detergent fiber digestibilities at 2 levels of dry matter intake. Journal of Dairy Science, 98 (1), 2015, 574-585.
• Sergio Calsamiglia, Marshall D. Stern, A three-step in vitro procedure for estimating intestinal digestion of protein in ruminants (1995). Journal of Animal Science 73 (5), 1459–1465.

 

 

 

 

Author Response

Thank you for your comments and observations. Please find enclosed the responses

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The manuscript is carefully prepared and is suitable for publication in Applied Sciences in its current form.

Reviewer 2 Report

I thank authors for their effort in addressing my comments. Authors´ answers were satisfactory for me.