Macroalgae Biorefinery for the Cosmetic Industry: Basic Concept, Green Technology, and Safety Guidelines
Round 1
Reviewer 1 Report
Dear Editor
I was very happy to read this script under the title (Macroalgae Biorefinery for cosmetic industry: basic concept, green technology, and safety guidelines). Really, I was enjoyed reading and review this valuable manuscript which contain huge information to those workers in this field. There are some sentences that need some modification, and I will attach them as a file for this arbitration.
Comments for author File: 
Comments.pdf
Author Response
Dear Reviewer,
Thank you for all your considerations and positive evaluation. All your relevant suggestions improved the quality of the manuscript.
Best Regards
Reviewer 2 Report
The manuscript entitled "Macroalgae Biorefinery for cosmetic industry: basic concept, green technology, and safety guidelines" addresses a topic that is relevant and suitable for this journal.
A profound correction in terms of the taxonomy of the mentioned algae has to be introduced, as indicated below.
Corrections needed:
line 60 - ments, i.e., fucoxanthin for brown (Phaeophyceae), phycobiliproteins for red (Rhodophyta),
line 103 - brown Fucus vesiculosus and green Ulva lactuca algae, and subjected them to liquid extrac-
line 145 - and Chow [44] on the Sargassum filipendula (Phaeophyceae) extract, subjected to radiation, which tends to
Table 2 - (Note: all species names cited in this table must be written in italics)
Is not Phaeophyta. The correct name is Phaeophyceae
Gymnogongrus durvillei (formerly Ahnfeltiopsis concinna)
Neopyropia yezoensis (formerly Porphyra yezoensis)
Gracilariopsis longissima (formerly Gracilaria verrucosa)
Porphyra umbilicalis
Codium tomentosum
Fucus vesiculosus
Caulerpa racemosa
Furcellaria lumbricalis
Ulva lactuca
Saccharina japonica
Cladosiphon okamuranus
Sargassum vulgare
----------------------------
Subtitle Phaeophycae (brown algae), Chlorophyta (green algae), Rhodophyta (red alga) (Note: not in italics)
line 270 - such as in Botryocladia occidentalis (Rhodophyta) ...
line 277 - erties, such as Gymnogongrus durvillei (formerly Ahnfeltiopsis concinna) extract and Chondrus crispus (Rhodophyta) extract. Regarding the
Table 3 - ... process for the preparation of agarose from Gracilaria and Gelidiella spp. (Rhodophyta), more
particularly Gracilaria dura and Gelidiella acerosa (Rhodophyta) from Indian waters, said
Carrageenan ...
line 367 - TC, FX, and phlorotannin (PT) from Saccharina japonica (Phaeophyceae). The results showed that 300 bar,
line 387 - yphenolic) fractions from Eisenia bicyclis (Phaeophyceae) extracted with solvents [87]. Indeed, phenolic
line 390 - macroalga Gracilaria gracilis [water, 120 oC, and 103 bar] [88]. However, other inexpen-
line 411 - biomass (a by-product from solvent extraction) of the brown algae Gongolaria barbata (formerly Cystoseira barbata) and
line 416 - for G. barbata and F. virsoides, respectively. ...
line 418 - of an upcycling approach by extracting agar from the red alga Gelidium corneum (formerly Gelidium sesquipedale) col-
line 434 - Pangestuti et al. [95] used this technique to hydrolyze Hypena musciformis (Rhodophyta) and obtain
line 438 - more, Caulerpa acemosa (sea grapes) and Ulva lactuca (sea lettuce) (Chlorophyta) were submitted to SCWE
Table 5 - Gongolaria barbata, brown
Gelidium corneum, red
Gongolaria barbata, brown
Ulva australis (formerly Ulva pertusa), green
line 641 - renewable raw materials, such as turmeric [84]. The macroalgae C. fragile, G. gracilis, L.
Author Response
Dear Reviewer,
Thank you for all your considerations and positive evaluation. All your relevant suggestions improved the quality of the manuscript.
Best Regards.
---
Q1: line 60 - ments, i.e., fucoxanthin for brown (Phaeophyceae), phycobiliproteins for red (Rhodophyta),
Answer: the sentence pointed out by the corrector has been corrected.
Q2: Line 103 - brown Fucus vesiculosus and green Ulva lactuca algae, and subjected them to liquid extrac-
Answer: the sentence pointed out by the corrector has been corrected.
Q3: line 145 - and Chow [44] on the Sargassum filipendula (Phaeophyceae) extract, subjected to radiation, which tends to
Answer: (Phaeophyceae) was added to sentence.
Q4: Table 2 - (Note: all species names cited in this table must be written in italics)
Answer: the entire table corrected regarding species names, italics inserted and formal names added
Q5: line 270 - such as in Botryocladia occidentalis (Rhodophyta) ...
Answer: (Rhodophyta) was added to sentence.
Q6: line 277 - erties, such as Gymnogongrus durvillei (formerly Ahnfeltiopsis concinna) extract and Chondrus crispus (Rhodophyta) extract. Regarding the
Answer: all taxonomic considerations have been added to the indicated sentence
Q7: Table 3 - ... process for the preparation of agarose from Gracilaria and Gelidiella spp. (Rhodophyta), more
particularly Gracilaria dura and Gelidiella acerosa (Rhodophyta) from Indian waters, said
Carrageenan ...
Answer: indicated corrections have been made and species classes added.
Q8: line 367 - TC, FX, and phlorotannin (PT) from Saccharina japonica (Phaeophyceae). The results showed that 300 bar,
Answer: (Phaeophyceae) was added to sentence.
Q9: line 387 - yphenolic) fractions from Eisenia bicyclis (Phaeophyceae) extracted with solvents [87]. Indeed, phenolic
Answer: (Phaeophyceae) was added to sentence.
Q10: line 390 - macroalga Gracilaria gracilis [water, 120 oC, and 103 bar] [88]. However, other inexpen-
Answer: species name italics added
Q11: line 411 - biomass (a by-product from solvent extraction) of the brown algae Gongolaria barbata (formerly Cystoseira barbata) and
Answer: the formal name of the species, as indicated, has been added
Q12: line 416 - for G. barbata and F. virsoides, respectively. ...
Answer: species name italics added
Q13:line 418 - of an upcycling approach by extracting agar from the red alga Gelidium corneum (formerly Gelidium sesquipedale) col-
Answer: the formal name of the species, as indicated, has been added
Q14:line 434 - Pangestuti et al. [95] used this technique to hydrolyze Hypena musciformis (Rhodophyta) and obtain
Answer: (Rhodophyta) was added to sentence.
Q15: line 438 - more, Caulerpa acemosa (sea grapes) and Ulva lactuca (sea lettuce) (Chlorophyta) were submitted to SCWE
Answer: (Chlorophyta) was added to sentence.
Q16: Table 5 - Gongolaria barbata, brown
Gelidium corneum, red
Gongolaria barbata, brown
Ulva australis (formerly Ulva pertusa), green
Answer: alterations were made to the species name for italics, as well as the addition of the formal names.
Q17: line 641 - renewable raw materials, such as turmeric [84]. The macroalgae C. fragile, G. gracilis, L.
Answer: the correct grammar has been inserted.
Reviewer 3 Report
This review paper provides an overview of the uses, and potential uses, of macroalgal biorefineries for producing ingredients or product components for the cosmetics industry. There is also an overview of green approaches to processing the macroalgae for extraction and purification of the various components, and also an overview of the regulatory environment for these products.
Overall, I thought that the manuscript was thorough and provided a nice overview. Perhaps some of the details that described the results of individual papers, especially in the sections devoted to extraction procedures, were perhaps excessive. Some of the descriptions of individual papers are very detailed, and I think that if a reader is interested in that level of detail, the reader would likely be happy to simply read the original paper.
I have a number of comments about specific parts of the manuscript. Some of the comments are minor, but some reflect places where the meaning of a sentence or section is not completely clear:
46 - What are “rushing paintings”?
48 – “Civilization Indumer” probably refers to the Indus Valley civilization?
78 – “Table 1. Putative efficacy of some chemical classes from macroalgae (2012 to 2022).”
The table heading indicate that the numbers in square brackets refer to literature references.
82 – “The main macroalgae polysaccharides are sulfated and include, alginates (1), fucoidan (2), and laminarin (3) in brown, agar (4) and carrageenan (5) in red, and ulvan (6) in green macroalgae.”
Agar and laminarin are not sulfated.
88 – “One of the most important functional requirements of polysaccharides is 88 that they must be stable during industrial process conditions such as high temperature, various pH, and ionic strengths”
Is this because the extraction of the polysaccharides occurs under those extreme conditions? This should be clarified.
92 – “2.2 Polyunsatureted Fatty Acids (PUFA)”
Polyunsaturated.
93 – “The physical and biochemical characteristics of PUFAs play an essential role in the survival and growth of microorganisms and aquatic animals in some hostile environments.”
Vague. Why are PUFAs important to the organisms that produce them?
104 – “Besides the application as nutraceutical, the authors found relevant antioxidant and antimicrobial activities.”
Were the anti-oxidant properties associated with the PUFAs, or with other components that were extracted?
133 – “and chelated metal ions [42]”
Phenolics can capture chelated metal ions? This requires clarification or explanation.
138 – “sargassaceae” should be Sargassaceae.
178 – “oxygenated photosynthesis”
Perhaps use “oxygen-evolving photosynthesis”?
183 – “skin barrier”
A skin barrier to what?
210 – “a consumer market increasingly adept of the campaigns of the so-called “green consumption”
I cannot understand the use of the word “adept” in this context.
218 – “As the market moves toward minimalist beauty, today’s consumer demands brands with cleaning up their products, while rising to meet their expectations”
What is meant by cleaning up their products?
221 – To what does “intelligence” refer?
225 – “that are in their surroundings”
Are the authors suggesting that the algal metabolic products are released to the aquatic environment by the macroalgae? This is not clear, but does seem to be what the authors are suggesting. However, “biogenic” compounds are compounds produced by organisms, and not necessarily compounds released by organisms.
INCI is not defined in the table heading for Table 2, but is only defined afterwards. INCI should be defined in Table 2.
253 = “the ponds”
What ponds are being described?
259 – “and then holding it there are hydrophilic substances.”
Does not make sense.
297 – “validating the safety 297 of the final product with equal accuracy.”
Does not make sense.
299 – “Nevertheless, the extraction process must be selected so that these compounds are 299 not wasted during the process of obtaining but rather used. Herewith, green processing emerges, which is the ideal choice to obtain improvements in the algae extraction process, as well as in aspects related to the economy in various directions of production, one of them being the reduction of energy consumption, and the transformation of waste into 303 by-products.”
I do not think that there is any evidence that green processing is more effective at extracting metabolites than conventional processing (which is implied in the above). Green processing is simply an alternative system that uses more environmentally friendly approaches.
338 – “brown algae” should be “brown alga” (there is only one species being addressed).
385 – “The extract recovered from PLE inhibited 100% 385 hyaluronidase activity”.
Not clear if that is desirable or not? Needs some explanation.
391 – Define “GRAS” when first motioned. Do not force the reader to do a web search.
432 – “It reveals that the practice of this technique may vary according to the structural characteristics of the raw material and solubility of the target compound.”
This is vague.
538 – “Furthermore, there is also the presence of Material Safety Data Sheets (MSDS)”
I suspect that MSDS has been mostly replaced by SDS.
604 – “in the biomass increase of macroalga (up to one week)”
I do not understand the suggestion of a one-week biomass increase. Time is not a measure of biomass.
612 – “Seghetta et al. [116] evidenced that 100% of macroalga biomass converted into a protein-rich fish feed, a liquid fertilizer, and ethanol reduces atmospheric CO2.”
Do the authors mean that less CO2 is emitted to the environment compared to non-integrated systems, or are the authors stating that this type of integrated system actually removes CO2 from the atmosphere? This is not clear, and if the suggestion is that there is net atmospheric CO2 removal, then the mechanism should be briefly explained.
625 – “As a first step, CO2-SFE substitutes a petrochemical solvent (e.g., hexane) to recover non-polar ingredients.”
The way that this sentence is written, it is implied that hexane replaces a different solvent. This is not what the authors are trying to state.
Author Response
Dear Reviewer,
Thank you for all your considerations . All your relevant suggestions improved the quality of the manuscript.
The writing of the text has been revised, and the Reviewer's questions were answered in the manuscript.
Best Regards
---
Q1: 46 - What are “rushing paintings”?
Answer: the correct term was rock paintings. It was substitute in the text.
Q2: 48 – “Civilization Indumer” probably refers to the Indus Valley civilization?
Answer: the correct was Civilization Indo-Sumerian. It was substitute in the text.
Q3: 78 – “Table 1. Putative efficacy of some chemical classes from macroalgae (2012 to 2022).”
The table heading indicate that the numbers in square brackets refer to literature references.
Answer: in order not to leave dubious ideas of interpretation, the interval of years was removed from the text.
Q4: 82 – “The main macroalgae polysaccharides are sulfated and include, alginates (1), fucoidan (2), and laminarin (3) in brown, agar (4) and carrageenan (5) in red, and ulvan (6) in green macroalgae.”
Agar and laminarin are not sulfated.
Answer: the new sentence presented in the text was: "The main macroalgae polysaccharides are sulfated, but in addition to these, the group includes and include, alginates (1)", thus replacing the misconception.
Q5: 88 – “One of the most important functional requirements of polysaccharides is 88 that they must be stable during industrial process conditions such as high temperature, various pH, and ionic strengths”
Is this because the extraction of the polysaccharides occurs under those extreme conditions? This should be clarified.
Answer: the new sentence presented in the text was: "One of the most important functional requirements of polysaccharides is that they must be stable during the industrial process when presented to the conventional method of alkaline extraction, where they are subjected to conditions such as high temperature, various Ph and ionic strengths. [33]". thus improving sentence clarity
Q6:92 – “2.2 Polyunsatureted Fatty Acids (PUFA)”
Polyunsaturated.
Answer: the correction was made in the text.
Q7: 93 – “The physical and biochemical characteristics of PUFAs play an essential role in the survival and growth of microorganisms and aquatic animals in some hostile environments.”
Vague. Why are PUFAs important to the organisms that produce them?
Answer: The sentence structure has been modified to: "The physical and biochemical characteristics of PUFAs play an essential role in the survival and growth of microorganisms and aquatic animals in some hostile environments. Because they are a primary source for its metabolism, participating as a structural component of cell membranes, and the concentrations of these PUFAs also vary according to temperature, environment, and season of the year, knowing that lower temperatures favor their production." Clarify what was asked.
Q8: 104 – “Besides the application as nutraceutical, the authors found relevant antioxidant and antimicrobial activities.”
Were the anti-oxidant properties associated with the PUFAs, or with other components that were extracted?
Answer: The sentence structure was modified to: "Besides the application as nutraceutical, the authors found relevant antioxidant and antimicrobial activities. Once the same study considers substances isolated from macroalgae with potent antimicrobial activity, belonging to polysaccharides, fatty acids, phlorotannins, pigments, lectins, alkaloids, terpenoids, and halogenated compounds, therefore, several compounds are involved in this activity, including these fatty acids."
Q9: 133 – “and chelated metal ions [42]”
Phenolics can capture chelated metal ions? This requires clarification or explanation.
Answer: The sentence structure has been modified to: "This formation of chelates is an antioxidant mechanism of flavonoids, where flavonoids containing carbonyl group in position four, and hydroxyl groups in position three or five, such as quercetin, rutin, kaempferol, myricetin, and morphine, form chelates with metal ions. This ability to sequester metal ions may contribute to its antiperoxidative properties by preventing the formation of free radicals" Giving clarity to what was asked.
Q10: 138 – “sargassaceae” should be Sargassaceae.
Answer: correction has been made to the text.
Q11: 178 – “oxygenated photosynthesis”
Perhaps use “oxygen-evolving photosynthesis”?
Answer: exactly, so the correction was made to the text.
Q12: 183 – “skin barrier”
A skin barrier to what?
Answer: and skin barrier against excess of solar radiations. This was add in text.
Q13: 210 – “a consumer market increasingly adept of the campaigns of the so-called “green consumption”
I cannot understand the use of the word “adept” in this context.
Answer: in this case, to add more meaning to the text in question, the word "adopt" was replaced by "engaged in" in the text.
Q14: 218 – “As the market moves toward minimalist beauty, today’s consumer demands brands with cleaning up their products, while rising to meet their expectations”
What is meant by cleaning up their products?
Answer: for better meaning, this sentence in the text was replaced by "As the market moves towards minimalist beauty, today's consumer even demands that brands clean their products of potentially harmful substances to the environment, meeting their expectations".
Q15: 221 – To what does “intelligence” refer?
Answer: to better understand the reason for using "intelligence" was added to the text "and intelligence, which is the presence of technologies capable of communicating the real conditions of a product or the environment in which it is found. "
Q16: 225 – “that are in their surroundings”
Are the authors suggesting that the algal metabolic products are released to the aquatic environment by the macroalgae? This is not clear, but does seem to be what the authors are suggesting. However, “biogenic” compounds are compounds produced by organisms, and not necessarily compounds released by organisms.
Answer: in this case, to add more meaning to the text in question, the paragraph was changed to "As aforementioned, macroalgae produce a wide variety of chemically active pri-mary and secondary metabolites, the secondary ones being known for their main purpose of protection against abiotic and biotic stresses. These active metabolites, such as halogenated com-pounds, alcohols, aldehydes, terpenoids are produced by several species of marine macroalgae, and have antibacterial, and antifungal properties, as in therapeutics [59]".
Q17: INCI is not defined in the table heading for Table 2, but is only defined afterwards. INCI should be defined in Table 2.
Answer: the INCI was defined in Table 2, as notified.
Q18: 253 = “the ponds”
What ponds are being described?
Answer: to better clarify, it was added to the text "Because of this, the sea, highlights in seaweeds, have become a great source of new materials for incorporation into cosmetic formulations ".
Q19: 259 – “and then holding it there are hydrophilic substances.”
Does not make sense.
Answer: to better clarify, it was replaced in the text "When it comes to skin smoothing, some ingredients are believed to be humectants that work by pulling water into the skin and retaining it, which are characteristics of ingredients based on hydrophilic substances. ".
Q20: 297 – “validating the safety 297 of the final product with equal accuracy.”
Does not make sense.
Answer: this sentence ended up being removed from the text, after this note.
Q21: 299 – “Nevertheless, the extraction process must be selected so that these compounds are 299 not wasted during the process of obtaining but rather used. Herewith, green processing emerges, which is the ideal choice to obtain improvements in the algae extraction process, as well as in aspects related to the economy in various directions of production, one of them being the reduction of energy consumption, and the transformation of waste into 303 by-products.”
I do not think that there is any evidence that green processing is more effective at extracting metabolites than conventional processing (which is implied in the above). Green processing is simply an alternative system that uses more environmentally friendly approaches.
Answer: for better content, it was changed in the text to "Nevertheless, the extraction process must be selected so that these compounds are not wasted while obtaining but rather used. Herewith, the combination of different green processing technologies emerges, which is the ideal choice to obtain improvements in the algae extraction process, as well as in aspects related to the economy in various directions of production, one of them being the reduction of energy consumption, and the transformation of waste into by-products. These green strategies, therefore, make the process an environmentally eco-friendly alternative, which is highly sought after soon."
Q22: 338 – “brown algae” should be “brown alga” (there is only one species being addressed).
Answer: the consideration has been noted and corrected in the text.
Q23: 385 – “The extract recovered from PLE inhibited 100% 385 hyaluronidase activity”.
Not clear if that is desirable or not? Needs some explanation.
Answer: to better clarify it was added to the text as follows: "The extract recovered from PLE inhibited 100% hyaluronidase activity (HAase, EC 3.2.1.35), ), there are desirable for the anti-aging activity, at concentrations similar to phlorotannin (polyphenolic ) fractions from Eisenia bicyclis extracted with solvents [87]".
Q24: 391 – Define “GRAS” when first motioned. Do not force the reader to do a web search.
Answer: Gras was defined and added to the text: "However, other inexpensive technologies with generally recognized as safe (GRAS) solvents may retrieve "
Q25: 432 – “It reveals that the practice of this technique may vary according to the structural characteristics of the raw material and solubility of the target compound.”
This is vague.
Answer: yes, it was vague, and methodology-specific information is already defined in the table, so that sentence has been removed.
Q26: 538 – “Furthermore, there is also the presence of Material Safety Data Sheets (MSDS)”
I suspect that MSDS has been mostly replaced by SDS.
Answer: yes, it was replaced because they are similar, in 2015, so the SDS was added to the text, and some additional information that differentiates it from the MSDS, such as: "safety precautions for handling, storing, and transporting the chemical. SDSs are required to be presented in a consistent user-friendly, 16-section format to help workers who handle hazardous chemicals to become familiar with the format and understand the contents of the datasheets. "
Q27: 604 – “in the biomass increase of macroalga (up to one week)”
I do not understand the suggestion of a one-week biomass increase. Time is not a measure of biomass
Answer: "up to one week of cultivation" was added to the text.
Q28: 612 – “Seghetta et al. [116] evidenced that 100% of macroalga biomass converted into a protein-rich fish feed, a liquid fertilizer, and ethanol reduces atmospheric CO2.”
Do the authors mean that less CO2 is emitted to the environment compared to non-integrated systems, or are the authors stating that this type of integrated system actually removes CO2 from the atmosphere? This is not clear, and if the suggestion is that there is net atmospheric CO2 removal, then the mechanism should be briefly explained.
Answer: for better understanding, this sentence was replaced in the text by:"Seghetta et al. [116] evidenced that 100% of macroalga biomass converted into a pro-tein-rich fish feed, a liquid fertilizer, and ethanol results in a net reduction of atmospheric CO2. In this simulation, macroalgae cultivation and soil's carbon retention were the key players in carbon footprint mitigation."
Q29: 625 – “As a first step, CO2-SFE substitutes a petrochemical solvent (e.g., hexane) to recover non-polar ingredients.”
Answer: the correct sentence was replaced in the text, and became: "As a first step, CO2-SFE is a substitute for a petrochemical solvent (e.g., hexane) to recover non-polar ingredients. "
Round 2
Reviewer 2 Report
The authors proceeded to introduce the corrections suggested by the reviewers, so that the manuscript can now be accepted for publication.
