The sea is a rich source of cosmetic ingredients. But there are not just algae, sand, sludge, salt, or water in the marine world! Invertebrates, a family of species which gathers most animal organisms living in this environment, might represent a new solution for cosmetic applications, especially in the perfume, sun care, or anti-aging sectors. Let’s immerse ourselves into a bone-free, but not futureless world!
Annelida, bryozoa, echinoderms, hemichordata, porifera, and other molluscs… With almost two million species already listed, marine invertebrates are said to constitute the largest part of the terrestrial biodiversity. And if many of these tiny animals are still little-known, they present such a potential that they are currently under study and have gained the interest of most distinguished researchers.
To Jean-Michel Kornprobst, a Professor emeritus at Université de Nantes, France, the cosmetic applications of marine invertebrates, which are an abundant, accessible, and rather cheap resource, are worth being explored. As an expert in the study of marine natural substances, he presented the main avenues to explore on the day of conferences held in Guingamp, last March 12, 2015, as part of the 6 th edition of U’Cosmetics. And they concern three particular fields: perfumes, UV-filters, and anti-aging.
Perfumes, Calone, and benzodioxepinone
Benzodioxepinone is an artificial aromatic molecule created and patented by Pfizer in 1966 under the designation, Calone 1951®, and later modified by Givaudan and Firmenich.
To Jean-Michel Kornprobst, it is the ‘ standard of marine fragrance’ , as it is present in great juices still on the market, like Escape for Her (Calvin Klein), L’Eau d’Issey pour Homme (Issey Miyake), L’Eau d’Eden (Cacharel), Polo Sport for Women (Ralph Lauren), Aquawoman (Rochas)…
No benzodioxepinone has been isolated from a marine invertebrate yet, but a few related molecules have from porifera devoid of mineral spikes, such as Dioxepine bastadin, in particular in the Ianthellidae family (Verongida order).
Its commercial exploitation remains hypothetical for now, the researcher added, but it is worth being included in the avenues to be pursued.
UV-filters, Zoanthoxanthins, and MAAs
Just like coral in coral reef, invertebrates live in the shallow areas of tropical marine waters and are naturally protected by substances which absorb UV rays.
These natural, anti-UV substances are particularly present in hexacorallia (cnidaria), echinoderms, molluscs, and ascidians.
MAAs or Mycosporine-like amino acids
They are derivatives of cyclohexenone and cycloheximine.
The former are bonded to an amino acid, while the latter bear an amino acid, and usually also a carboxylate group and/or a sulphur residue.
These small molecules (M ≤ 400 Da) absorb UVs in the range 310-340 nm (UVAs and UVBs) and do not present any toxicity hazard (Study by La Barre, Roullié & Boustié, Mycosporine-like Amino Acids (MAAs) in Biological Photosystems, in Outstanding Marine Molecules , La Barre & Kornprobst, Eds., Wiley-Blackwell, 2014, 333-359).
MAAs have already been isolated from hexacorallia corals:
• Mycosporine-glycine from Palythoa tuberculosa
• Mycosporine-taurine from Anthopleura elegantissima
• Palythine-threonine from Pocillopora capitata…
Other invertebrates also made it possible to isolate MAAs:
• Aplysiapalythine C from Aplysia californica (a mollusc)
• Asterina-330 from Asterina pectinifera (an echinoderm)
• Z -Palythenic acid from Halocynthia roretzi (an ascidian)…
Zoanthoxanthins are a family of nitrogenous pigments specific to hexacorallia coral of the Zoantharia order ( Epizoanthus, Palythoa, Parazoanthus, Zoanthus ). All these nitrogenous pigments are composed of two imidazoles joined with a cycloheptatriene (most frequently) or cycloheptadiene unit.
Several have already been isolated from invertebrates:
• Zoanthoxanthin from Parazoanthus axinellae
• Pseudozoanthoxanthin from Epizoanthus arenaceus
• Epizoanthoxanthin B from Epizoanthus arenaceus
• Zoamide D from Parazoanthus sp.
Palythoa variabilis could also be a source of zoanthoxanthin. At least, Jean-Michel Kornprobst took some from tropical waters for L’Oréal for research purposes … but he specified he was not informed of the result of the experiments.
In the field of sun care, if algae can now provide documented UV-filters for which cosmetic applications have been found (see our article entitled Algae: a world (of actives) yet to be exploited (Part 2) – soon available online), invertebrates still have not actually been exploited… but it is a possibility that might soon become real.
Anti-aging, collagens, and enzyme inhibitors
Here is a short reminder.
Collagens are structural (fibrous) proteins present in abundance in the connective tissue (extracellular matrix) of the animal kingdom. They are inextensible and exhibit a high tensile strength. There are about thirty collagens, but type 1 is the most important for cosmetic applications. It can be found in particular in tendons and in the skin, where it ensures the dermis remains firm, but its renewal declines with age. Both vertebrates (like in the human body) and invertebrates have collagens.
Elastin is also a structural protein. It is extensible, elastic, and very abundant in soft tissue. Its synthesis declines with age and it is gradually replaced by inextensible collagen, hence its use in cosmetics. It can be found in vertebrates, but not in invertebrates. At least, as Jean-Michel Kornprobst explained, ‘it is considered absent until proven present’. Then he gave the example of octopuses: ‘their tentacles are so extensible and elastic… if this is not elastin, it must be close!’
There are numerous marine collagen-based specialties on the market, and they are all obtained by controlled hydrolysis of fish skin or cartilaginous fish cartilage (rays and sharks).
Most marine collagens are enriched in vitamin C, and some are also rich in heavy cations like zinc and manganese, which act as co-factors of the enzymes that produce them.
If the vast majority of the marine collagens available on the market come from fish, there are still other sources originating from invertebrates, mainly jellyfish.
Jellyfish collagen can be found on the Asian market. Europe seems more reluctant to capitalize on it for now, although to Pr Kornprobst, it is a very promising resource. As an example, Rhizostoma pulmo , a Mediterranean species, contains 2 to 10 mg of type 1 collagen per gram of dry tissue.
However, the researcher does admit the process of extracting jellyfish collagen is not very profitable: indeed, these animals can contain 95 to 98% of water (‘ more water than in seawater!’ , he underlines). Therefore a maximum of one kilogram of collagen only could be extracted from one ton of jellyfish.
Little by little, collagen and elastin are degraded by specific enzymes, collagenases and elastase, which belong to the broad family of MMPs (matrix metalloproteinases or matrixins). Any inhibitor of these enzymes will thus prove particularly useful in anti-aging preparations.
The study of structure-activity relationships showed an MMP inhibitor should meet three conditions:
• Have a functional group able to chelate the zinc of the active site (hydroxamate, carboxylate, thiolate, phosphinyl)
• Have at least one donor functional group with a hydrogen bond to interact with the enzyme
• Have one or several lateral chains to allow for an interaction with the active site of the enzyme by Van der Waals bonding.
MMP inhibitors are particularly sought for their medical applications, and there are many examples of synthetic ones. ‘Looking for an MMP inhibitor in invertebrates is like looking for a tiny needle in a haystack’, Pr Kornprobst explained, ‘it is easier to synthesize it!’
Nevertheless, there is a concrete example of an elastase inhibitor: a glycosylated Diterpene (saponin) was isolated from a Caribbean sea plume, Pseudopterogorgia elisabethae, and incorporated into Estée Lauder anti-wrinkle creams: Resilience™ and Resilience Lift Extreme™.
It is also known that terrestrial annelid extracts show anti-elastase, anti-tyrosinase, and anti-MMP-1 activities. It might therefore prove particularly interesting to study marine annelida to this aim.
In any case, exploiting marine invertebrates for cosmetics is full of promises.
So it is now up to marketing departments to make consumers want to use them on their skins and overlook both the rather strange names of these invertebrate extracts, and their equally odd appearance. There are exciting challenges ahead for the cosmetics industry!