Optimized Extraction of Passiflora ligularis Pectins: Characterization and Application in Moisturizing Cosmetic Products

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Detailed Comments for Authors

The following comments are provided to help enhance the quality of the manuscript. Please check one by one:

Page 1

• Line 26-27: Change the sentence "In vitro assays confirmed significant moisturizing activity" to in vitroassays were performed moisture retention in test.
• Line 30-31: keywords: rewrite based on the mesh.
• Line 42: Add reference.

Page 2

Line 47: Add a reference.

Line 54, 66, 69, 72: scientific names must be in italic style. check the whole document and correct it.

Line 76-77: Add the information of the domestic place.

• Line 79-80 (Plant material): specify the particle size range achieved after sieving.
• Line 86: brief this 18 trials.
• Line 88: add reference.
• Page 3
• Section 2.4: Define "meq A NaOH" and "meq B NaOH" in the text for clarity.
• Line 111-113: add references.
• Line 127: specify the centrifugation conditions (speed, time, temperature).

Page 4

• Table 1 and Table 2:These tables are currently very confusing. Table 2, in particular, is difficult to interpret. Replace Table 2 with a new table that lists all treatment names in the first column to clarify.
• Line 151: italic style
• Table 2: Check the F3 for TEA
• Section 2.7: The text describing the formulations is fragmented. After introducing the new, clear table2 for F1-F8, this section can be significantly rewrited to describe the data differences and referring readers to the table for specific discussion.

Page 5

• Section 2.8: the methodology is too subjective. How "homogeneity," "texture," and "phase separation" was scored? Do the viscosity measured with a viscometer? Please describe the evaluation criteria in more detail by the instruments informations.
• Page 6

Line 212-213: It is repeated of line 209-210. eliminate the final sentence.

Page 7

• Table 4: The footnote "* Pectin precipitation was not achieved" for experiments E9, E10, E12, E14 is crucial. Please add a sentence in the main text discussing the potential reasons for this and how it was handled in the yield calculation. Also, write in the footnote that what is the treatments E1-E16.
• Line 259: where is the interaction plots?
• Line 271-273: how many sample used for each analysis? do you have just one treatments as best one or combine the results of 16 treatments? it was better to bring all 16 treatments results separately.
• Line 278-279: add reference.

Page 8

• Line 279-281: expand this conclusion and discuss based on your results.
• Line 295: could you have a discuss on functional groups by FTIR results vision? it will be very helpfull.
• Line 305: have a discussion and go to the next sentence as conclusion.

Page 9

• Line 319-322: Check it again.
• Figures 2: Please ensure high-resolution images are submitted with clear labels for key peaks/signals.

Page 10

Tabe 6: you must change the heat and cold stability, Viscosity and sensory changes, and precipitation from qualtitative report to quantitative/semiquantitative report by statistical analysis. Also show the pH "fluctuation". it is very important for a high quality article.

Line 351-355: have additional discussion for suitable pH for skin care products and your results comparison.

Page 11

• Section 3.4: The text describes F8 as the best, but the data in Table 6 does not robustly support this over F7. More work to justify to be stronger and directly linked to quantifiable observations.
• The photostability results are described qualitatively. Please add any quantitative or semi-quantitative observations if possible.
• Page 12
• Conclusions: The conclusion that Formulation 8 was the best is not fully supported by the presented data (check the F7). Please ensure the results section provides the necessary evidence for this claim.
• Line 418: eliminate "please add"

Comments on the Quality of English Language

The manuscript requires language editing by a native English editor/editor service. Here are some, but not all, corrections need for enhancing English language:

• Page 6, Section 3.1, line 219: "yielded with more suitable physical characteristics" –must be rewrited as yielded pectins with more suitable physical characteristics.
• Page 7, Section 3.2, line 259-260: "the microwave–citric acid combination was the most effective condition" could be rewrited to the combination of microwave assistance and citric acid solvent was the most effective condition for better grammer.
• Page 11, line 368: "Olfactory analysis showed a generalized loss of aromatic intensity..." could be rewrited to "A general reduction in aromatic intensity was observed..." for more formal tone.
• Page 11, Line 382-385: "formulation is photosensitive, highlighting the need for opaque or UV-protective packaging, as well as storage instructions to avoid direct sunlight, in order to preserve integrity and efficacy during consumer use", This is a long sentence and could be break up to two different sentence.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Cosmetics-3925977

Optimized Extraction of Passiflora ligularis Pectins:

Characterization and Application in Moisturizing Cosmetic Products

1. Summary of the Manuscript

This manuscript reports on the optimization of pectin extraction from the peel and mesocarp of Passiflora ligularis (granadilla), a fruit abundant in Colombia, using various methods including hot-water reflux, acid extraction and microwave-assisted extraction. A factorial design was employed to evaluate factors such as solvent, method, temperature, and time, with yield as the response variable. The pectin was incorporated into eight gel-type cosmetic formulations, evaluated for preliminary 7-day stability and tested in vitro for moisturizing activity. The study positions P. ligularis pectins as sustainable natural polymers for cosmetic applications, leveraging agro-industrial by-products.

The manuscript addresses a timely topic in cosmetic science, focusing on sustainable, natural ingredients from underutilized agro-industrial waste. The use of P. ligularis pectins as moisturizing and gelling agents aligns with growing demand for green cosmetics. The experimental design is sound, and the characterization data support the claims of high water-retention potential.

However, the study has limitations in depth, such as limited stability testing (only 7 days), absence of advanced statistical analysis for the factorial design, and no comparative data with commercial pectins. There are also inconsistencies in reporting and minor language issues. The novelty is moderate, as pectin extraction from Passiflora species has been reported, but the application to moisturizing gels from this specific species adds value. With revisions, this could be a solid contribution to the journal.

1. The experimental design is appropriate, but results lack detailed statistical analysis.

The response surface or main effects are not visualized, making it hard to verify optimization claims. The optimal yield (45.23%) is high, but compare it quantitatively to literature values for other Passiflora or fruit pectins to highlight superiority.

2. While moisture, acidity, methoxyl, DE, swelling, and water retention are reported, interpretations of ATR-FTIR and NMR spectra are superficial. The DE (57.6%) classifies it as high-methoxyl pectin, but discuss implications for gelling
3. . No molecular weight, purity or rheological data are provided, which are crucial for cosmetic applications. In vitro moisturizing assays are mentioned but not detailed describe methods, controls, and quantitative results.
4. Eight formulations (F1-F8) incorporate 5% pectin with variations in rheology modifiers (carbomer, guar, TEA) and pH adjusters. However, stability is only preliminary (7 days at room temperature ?). Organoleptic and physicochemical evaluations (pH, viscosity, homogeneity) are vague provide specific metrics and criteria for "stable." No microbial challenge testing or skin irritation assays are included, despite claims of skin compatibility. Compare performance to a commercial pectin-based gel.
5. The abstract states "significant moisturizing activity" from in vitro assays, but details are absent. Without data, these claims are unsubstantiated. Link characterization directly to moisturizing via mechanisms. No in vivo or ex vivo tests are mentioned consider adding or noting as a limitation for future work.
6. While using Colombian agro-by-products is regionally relevant, similar extractions from Passiflora edulis or other fruits exist. Emphasize unique aspects (e.g., microwave optimization for energy efficiency) and quantify sustainability (e.g., waste valorization metrics, carbon footprint reduction). The introduction overstates skin aging links without tying back to pectins specifically.

We recommend Major Revision.

The manuscript has strong potential due to its practical focus on sustainable cosmetics, but requires enhanced data analysis, deeper characterization, expanded stability/moisturizing results, and clearer novelty claims.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The authors attempted to obtain pectin (P. ligularis) from agricultural and food industry by-products, proposing it as an alternative for cosmetics. The subject matter of this article is topical and important in terms of knowledge. The cosmetics market is constantly looking for new raw materials with skin moisturizing properties.

COMMENTS:

- Abstract, p. 27 - The authors did not measure moisturization in their research, so how did they confirm this effect?

- p. 43, p. 2 - please list which moisturizing substances are used in cosmetics

- p. 70, p. 2 - please clarify the sentence. Why is its use limited?

-l.70-l.73, p.2- the authors did not assess the degree of skin hydration. The purpose of the article was not to evaluate the moisturizing effect. This must be changed

- In Table 2, glycerin should be written with a capital letter.

- Information about cosmetic raw material companies and their concentrations is missing (were all raw materials 100%?).

- Point 2.8 - Was a point scale used for visual assessment? If so, which one?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

In this work, the authors have depicted an optimized extraction of pectin from the Passiflora ligularis residues. This biopolymer has shown significant promise in cosmetic applications including its gelling capacity, water retention, and consumer-acceptable sensory attributes.

The strengths of this manuscript are as follows.

• The research is novel. Pectin derived from the Passiflora ligularis residues has not been explored prior for its cosmetic/ moisturizing applications.
• The research is comprehensive and organized. The controls are chosen properly so that the logical comparisons can be made. All the claims are supported with experimental data.
• The citations are appropriate.

Suggestions for edits are as follows.

1. Page 9, Figure 1 and Figure 2. It will be easy to follow if the authors can elaborate the figure caption with slight details, i.e., what do the peaks or highlighted areas in the IR and NMR spectra suggest?
2. Page 11, Table 7. The columns need to be spaced out slightly so that the texts do not look congested.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I review the revised manuscript and your responses. It is good job. Now the quality of the manuscript is enhanced. Just it is better to write "In vitro" in italic style as a scientific rule.