Natural skin tanning occurs due to UV exposure. Ultraviolet rays increase melanin production in the skin, giving it color. Melanin is the skin's natural pigment and defense system. Either reducing skin's resistance to UV rays (which can be difficult) or increasing its potential to produce melanin can increase the degree of tanning.
Tyrosinase is the enzyme responsible for converting the amino acid tyrosine to Dopa and initiating melanin biosynthesis. When tyrosine is applied topically to the skin, an additional reserve is stored to help drive melanin synthesis in the epidermis, thereby increasing and prolonging the tanning process. Tyrosine must be applied in a bioavailable form in order for it to function as a tan activator. When applied to the skin, tyrosine is released from the Brookosome® TA into the epidermal layers, where it can augment the activity of tyrosine already present in the skin. The tyrosine derivative becomes active upon its oxidation by cutaneous enzymes, increasing melanin production and enhancing the tanning process.
The addition of a bioavailable form of zinc to Brookosome® TA enhances the tanning effects on the skin. Zinc is an important nutrient necessary for the healing and development of new cells. The ion is a key cofactor in many enzymes, such as DNA and RNA polymerases, and in other enzymes involved in protein synthesis, and in carbonic anhydrase during the conversion of carbonic acid to carbon dioxide and water. It is involved in the biochemical reactions of the extracellular matrix. For instance, zinc plays a key role in dermal turnover, including the healing process and NMF production. Deficiencies may result in prolonged wound healing, stretch marks, white spots on the nails, and susceptibility to infections. Zinc also plays a key structural role in Superoxide Dismutase, a cellular antioxidant that is part of the cell's natural defense system.
Feeding yeast cells nutrient media high in zinc levels allows manufacturers to take advantage of the yeast cells' natural metabolic processes. Zinc is bound to cellular glycoproteins within the yeast cell. The extract from these yeast cells provides the mineral in a "bioavailable" form, a state shown to enhance mineral delivery to the skin. The yeast-glycopeptide mineral complex represents an ideal way to incorporate important elements into formulations for topical applications.Brookosome® TA has been developed as a bioavailable source of zinc and tyrosine to enhance skin tanning. Natural pigmentation and healthy-looking skin can be optimized by the presence of these actives. The addition of these active components to a liposome or Brookosome® enhances their ability to penetrate the skin and protects the actives in a formulation.
