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Welcome to my beauty blog, and you will find a lot of beauty sharings here. As a shopaholic and a skincare maniac, I always like to try new things in market. And the most important thing is I just share what I had tried for at least a month to get most trustworthy testimonial. Besides, as a cosmetic analyst, I'll share with you more interesting facts behind these bottles and jars. Feel free to drop by here and I am looking forward to approaching you soon.

Friday, September 3, 2010

Beauty info:Melanin Formation

Melanin determine our skin tone color. Typically, melanin exist in two types: eumelanin & pheomelanin. Eumelanin is dark brown, bigger spot and distribute evenly; Pheomelanin are yellowish red, smaller spot and centralized. Black men have more eumelanin while white men tend to have more pheomelanin, Asians are in between two of them. Gene will determine the amount and type of melanins, thus decide your skin tone whether look fair or dark.

The first step of the biosynthetic pathway for melanin is catalysed by tyrosinase:

Cu2+ → Tyrosinase → L-tyrosine → DOPA → dopaquinone → Melanin

Dopaquinone can combine with cysteine to pheomelanins. Alternatively, dopaquinone can be converted to leucodopachrome and follow two more pathways to the eumelanins.

Dopaquinone + cysteine → 5-S-cysteinyldopa → benzothiazine intermediate → pheomelanin

Dopaquinone → leucodopachrome → dopachrome → 5,6-dihydroxyindole → quinone → eumelanin

The degree of melanin formation is depends on
1) relative concentrations of copper and of the copper-containing enzyme tyrosinase
2) UV rays exposure
3) stress/pressure
4) hormone changes during pregnancy
5) lack of sleep


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