In yet another nod to the power of serendipity, Norwegian salmon hatchery workers noticed that their hands became soft and felt smooth after exposing them to cold hatching fluid from the salmon. Healthy hands are unusual, as swollen, red chapped skin is the normal status of hands after long exposure to cold water.

Scientists searched for the explanation for the smooth skin and eventually discovered an enzyme they called Zonase that helps the fish embryo get out of its eggshell. The eggshells consist of a tough, fibrous protein structure and the fish larva is not able to escape on mechanical power alone. This enzyme helps to digest the eggshell without harming the larva, thus allowing the fish to be born.

This enzyme extract has been commercially produced by a Norwegian company called ABT (Aqua Bio Technology Asa). The trade name is Aquabeautine XL (INCI: Hydrolyzed salmon egg shell extract). In the US, it is available from Strategro International, West Orange, NJ.

Although the material is animal derived, the larvae are not harmed—only the surrounding fluid is harvested. The concept is similar to lanolin harvesting, where the material is removed from sheared sheep wool.

The dead outer layer of human skin is shed before new skin can regenerate and emerge. Mechanical processes, such as brushing, or chemical means, such as acid exfoliates, which can damage the skin, have been used.

It is claimed that the Zonase digests only the links between the dead skin cells, leaving the living cells untouched which makes this treatment selective, gentle and efficient.

Aquabeautine XL contains the Zonase enzyme along with other proteins from the hatching fluid. The optimum use pH for it is 7.5, although it is still active at pH 5.0.In a basic emulsion formula, it has been stable in sealed containers at room temperature for three years. In vitro testing on reconstructed human epidermis showed that Aquabeautine XL was comparable to alpha and beta hydroxyl acids such as glycolic, lactic and salicylic acids within 24-48 hours of exposure. It does not have to be removed or inactivated like the acids.Other studies showed that it was non-allergenic, non-mutagenic,non-irritating and non-sensitizing on 100 subjects during six weeks.

Some summarized advantages of this product are:

• 100% natural and biodegradable derived from a sustainable source;

• Biospecific exfoliant gives comparable results to hydroxy acids without skin irritation;

• Moisturization, skin rejuvenation and soothing effect;

• Safe and non-toxic;

• Stable for years unlike other proteases;

• Colorless and odorless; and

• Suitable for wide range of cosmetics including sensitive skin products.

The following formula illustrates the use of Aquabeautine XL

After-Sun Cream Gel

Procedure:

Mix constantly. After acrylates/C10-30 alkyl acrylate crosspolymer is wet out and dispersed, add other phase A ingredients and heat to 60°C. In a separate container, heat phase B to 60-65°C and add to A. Cool to 35-40°C and add phase C. Adjust final pH to 6.5-7.0 with diluted sodium hydroxide. A preservative should also be added.•

Harvey Fishman has a consulting firm located at 34 Chicasaw Drive, Oakland, NJ 07436, [email protected], specializing in cosmetic formulations and new product ideas, offering tested finished products. He has more than 30 years of experience and has been director of research at Bonat, Nestlé LeMur and Turner Hall. He welcomes descriptive literature from suppliers and bench chemists and others in the field.