Changes in Skin Elasticity and Firmness Caused by Cosmetic Formulas Elaborated with Essential Oils of Aristeguietia glutinosa (matico) and Ocotea quixos (ishpingo). A Statistical Analysis
Round 1
Reviewer 1 Report
The manuscript is well written and presents interesting findings into the use of essential oils for skin elasticity and firmness. Please see comments below for improvements required before publication:
Page 2, Tables 1 and 2: a clearer statement mentioning that these will be the formulations used in the study is needed. As it is now, it is a bit vague, and confusing.
Page 2, materials, and methods: A short statement on how the creams/lotions were characterized and deemed suitable for use by volunteers will be useful.
Page 3, Table 3: Please define age 2 and 3 groups in the main text of the introduction
Page 4, line 87: could the authors expand more on the standardized procedure?
Page 5, Figure 1: A representation of the error values (through error bars) for the adjusted means is needed on the figure itself rather than a general statement in the body of the text.
Page 6: The work needs some further explanation to why there is a difference in the performance of the creams between both age groups. Also, what is the possible effect of the differences observed in T2 and T3 on how the readers could view the data and in terms of the creams/lotion efficiency.
Author Response
Please see the attachment.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comments:
1. The Methods section recommends describing how ethical principles were ensured during the study. Indicate the ethical permission to obtain the study, if any.
- Describe the study sample size. It is appropriate to indicate the sample size in section 2.2.
- Describe the statistical tests applied to the analysis of the results.
- Adjust the numbering of methods (there are currently two sections 2.3)
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Reviewer 3 Report
The use and application of two oils extracted from native plants in skin care formulations is presented in this manuscript, being an interesting essay to study efficacy evaluation of cosmetics incorporating Aristeguietia glutinosa (matico) and Ocotea quixos (ishpingo). In the present form of the manuscript there can be found some technical weaknesses of approach, instrumentation, and/or interpretation. Also, poor quality of English language is used including grammatical mistakes, which also abounds in the manuscript.
I permit to give some suggestions, which could enhance the quality of your manuscript:
Introduction
Line 33: Please use scientific terms regarding “spots on the skin”- I suggest for e.g hyperpigmentation or solar lentigines
Authors should explain the reason of developing two formulations (cream and lotion), because the concentration of the oils is the same in both cosmetics. Also it should be considering that essential oils are mostly used as fragrance ingredients (also taking into consideration their irritant potential), while natural (or synthetic oils) are used in cosmetics as emollients.
Materials and Methods
Some details in this section need to be more detailed. All experiments should be written in detail in order or make clear for readers who are interesting to conduct a similar research.
The preparation method of the cream and lotion is not described, which I indicate to be mentioned for both formulations.
Line 63: please correct after “.”- “in this case…” (“In…”)
Authors should mention the physico-chemical properties of the obtained formulations, not just indicate a reference.
I would suggest that Table 1. and Table 2. should also include the function of the ingredients in the cosmetic formulations.
Please use correct denomination of INCI- International Nomenclature of Cosmetic Ingredients (Line 71 and 79).
Authors mentioned a O/W emulsion type for the developed cream, the emulsion type of the lotion should also be mentioned.
As inclusion criteria of subjects, authors mention “The benefits they receive from applying cosmetic formula are higher than the risks”, which personally I don’t considerate an inclusion criteria for subjects in clinical trials.
Also, I would recommend to use “subjects” instead of “volunteers”.
Line 81-82: Please use “Justify”.
It is indicated that cutometry was used for instrumental evaluation of elasticity using the Cutometer MPA 580®- I suggest to mention in (Courage + Khazaka Electronic GmbH, Köln, Germany). Also regarding efficacy evaluation there should be mentioned references regarding cutometry and subject selection according Glogau scale. For e.g:
- Monteiro Rodrigues, L., & Fluhr, J. W. (2019). EEMCO Guidance for the in vivo Assessment of Biomechanical Properties of the Human Skin and Its Annexes: Revisiting Instrumentation and Test Modes. Skin Pharmacology and Physiology, 1–16. doi:10.1159/000504063.
- Ohshima, H., Kinoshita, S., Oyobikawa, M., Futagawa, M., Takiwaki, H., Ishiko, A., & Kanto, H. (2012). Use of Cutometer area parameters in evaluating age-related changes in the skin elasticity of the cheek. Skin Research and Technology, 19(1), e238–e242. doi:10.1111/j.1600-0846.2012.00634.x.
- Krueger, N., Luebberding, S., Oltmer, M., Streker, M., & Kerscher, M. (2011). Age-related changes in skin mechanical properties: a quantitative evaluation of 120 female subjects. Skin Research and Technology, 17(2), 141–148. doi:10.1111/j.1600-0846.2010.00486.x.
- Kawałkiewicz, W., Matthews‐Kozanecka, M., Janus‐Kubiak, M., Kubisz, L., & Hojan‐Jezierska, D. (2020). Instrumental diagnosis of facial skin – a necessity or a pre‐treatment recommendation. Journal of Cosmetic Dermatology. doi:10.1111/jocd.13638.
- Katz, B.E., Lewis, J., McHugh, L., Pellegrino, A., Popescu, L. (2015). The Tolerability and Efficacy of a Three-product Anti-aging Treatment Regimen in Subjects with Moderate-to-severe Photodamage. J Clin Aesthet Dermatol. 8(10),21-26.
Authors mention about sensory performance, but no other details are described. Please specify in this section all methods for the sensory assessment, there is no description of the method, none details are given at least in the Results and Discussion section. Please mention details about the sensory analysis- panel assessors, followed attributes, sample evaluation method etc.
Results and Discussion
It would be very interesting if authors could provide a statistical analysis of the sensory properties mentioned in the Materials and Methods section, and their correlation (eventually another experimental design) with the developed formulations and also instrumental evaluation.
Figure 1 and Figure 2- please use English for Figure Titles/Descriptions (Line 126 and Line 157).
Line 174/176/178- I recommend at least to indicate in the text the name of the author(s) regarding a mentioned study, not a bibliographic reference.
Conclusions
Line 182- Personally, I don’t find proper the expression “without sandy textures”.
Line 183- I suggest “fragrance” instead of “aroma” regarding cosmetics characteristics/organoleptic properties.
Personally, I find unnecessary aspects expressed in Lines 189-196. The authors should focus on the subject from their studies.
Reference
Taking into consideration, that current literature offers a multitude of data regarding novel anti-ageing formulations and efficacy evaluation, authors should revise Refrence section according to Cosmetics Instructions for Authors.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The authors have addressed the comments, and in my opinion, the manuscript is ready for publication.
Author Response
Dear reviewer,
We appreciate your comments and suggestions made on the manuscript.
Best regards,
Authors
Reviewer 3 Report
Dear authors,
thank you for the opportunity to review the manuscript, now in its revised form.
Authors are congratulated for the substantial improvements they have made with regards to the comments provided.
My review of the revised submission will be additionally focused on some key points:
Line 75
- Table 1
"Glyceryl stereate"- please correct "Glyceryl stearate"- emollient/emulsifying as ingredient function according INCI Database
"Stearic acid"- emulsifying/emulsion stabilising
"Cetyl alcohol"- emollient/emulsifying
"Crodamol GTCC"- emollient/solvent
"Xiameter Silicone DC 245"- is the commercial denomination Dowsil TM 245 Fluid?
*International Nomenclature of Cosmetic Ingredients
Line 91
- Table 2
"DC RM 2051"-is the commercial denomination Aculyn TM RM 2051?
- thickening agent/emulsifier
"DC 556"- is the commercial denomination DOWSIL™ 556 Cosmetic Grade Fluid?
- emollient
"Xiameter silicone DC 245"- is the commercial denomination Dowsil TM 245 Fliud?
*International Nomenclature of Cosmetic Ingredients
Best regards,
the Reviewer.
Author Response
Dear reviewer,
We appreciate your comments and suggestions made on the manuscript.
We have made the following changes:
Line 75 Table 1
Correction of the term "Glyceryl stearate"
The functions according to the INCI Database were added to:
"Stearic acid"- emulsifying/emulsion stabilising
"Cetyl alcohol"- emollient/emulsifying
"Crodamol GTCC"- emollient/solvent
"Dowsil TM 245 Fluid"
The letter "s" was included at the end of the Internationa Nomenclature of Cosmetic Ingredients
Line 91 Table 2
The commercial names of the ingredients were changed to those suggested by the reviewer.
The letter "s" was included at the end of the Internationa Nomenclature of Cosmetic Ingredients
Best regards,
Authors
Author Response File: Author Response.docx
