All whitening products have one purpose, to make the skin look whiter. A good whitening product has at least one or N whitening ingredients at work, each working in its own way, in order to reduce skin melanin and successfully achieve the first stage of the [white and rich] goal.
|Extracellular signals such as UV light, acidic and alkaline stimuli, and inflammatory signals send help signals to the melanocytes to activate them
|Melanocytes are the equivalent of melanin synthesizing factories, with a rigorous internal production line to continuously synthesize melanin.
|Melanin is synthesized and transported to the epidermal cells through specialized tubes
|Inhibits melanocyte activator transport
|Melanin is synthesized and transported to the epidermal cells through specialized tubes.
|Inhibit melanocyte activity
|Inhibits melanin transport
|Accelerates melanin metabolism
However, a variety of whitening ingredients work principle, effect is not the same.
(1) arbutin body hidden whitening energy huge [hydroquinone] nucleus, but the set of glycosidic bond, like wearing a “tight band” of the Monkey King, obedient, focused on the role of tyrosinase activity center, inhibit the activity of melanocytes, the production line of the most important machine – – “tyrosinase”, the most important machine – – “tyrosinase”, the most important machine – – “tyrosinase”. -Tyrosinase”, the most important machine in the production line, to reduce the synthesis of melanin. But the “spell” is not foolproof, arbutin may be subjected to high temperature, pH, light and other factors, hydroquinone hydrolysis, arbutin high additive amount of cytotoxicity.”
(2) Vitamin C, like a versatile multi-talented, many skills, but not a few is the top, however, “their own temperament is also quite a lot of”, it is easy to inactivate denaturation. Vitamin C for skin whitening, in fact, contributes a lot of skills, VC itself acidic can promote the exfoliation of the stratum corneum, VC powerful antioxidant can be [part of] slowing down the oxidation reaction of melanin synthesis, but it is a pity that the prototype of the VC is too difficult to HOLD, so that people love and hate.
(3) in these three whitening ingredients, may be the most concerned about the most want to understand the whitening ingredients is niacinamide. Niacinamide, a hot ingredient in the last 5-10 years, has made a name for itself in the world of whitening ingredients with the unique skill of “inhibiting melanin transit”. About niacinamide in fact, there are a lot of anecdotes, we know one and do not know the other, here would like to start talking about.
From the principle of whitening (see Figure 1), niacinamide’s target is the melanin transport stage, like a halfway kill out of the “Cheng Bite Jin”, guarding the main road of melanin transportation, to prevent the transfer of melanin, a man who is the gateway to a million can not be opened, simply can not be too good. However, organisms are subtle and precise, let me share with you the first set of data, the transfer inhibition of melanosomes: in the co-culture experiment of melanocytes and keratinized cells, after 3 days of nicotinamide-treated samples, nicotinamide inhibited the amount of melanin transferred from melanocytes to keratinized cells by 14%. In other words, the industry rumor that “niacinamide inhibits melanin transfer” is true, but the efficiency is not high, only 14%.
Next is the second set of data, human clinical trials: 2% and 5% niacinamide were applied in human clinical trials, after 4 and 8 weeks, 2% niacinamide did not have a significant effect on facial hyperpigmentation (Figure C below), while the 5% niacinamide group showed a more significant reduction in the effect of hyperpigmentation (Figure D below).
In other words, low concentrations of niacinamide actually have a minimal effect on melanin transfer, so 5% is not bad if you want to whiten your face with niacinamide. However, the high concentration of niacinamide also brings the problem of “tolerance”, which is not friendly to many skin types. Niacinamide in the production process is prone to residual niacin, niacin will lead to skin capillary dilation, the skin is prone to redness, itchy and tingling conditions, sensitive skin need to be careful to choose.
The third group of data, the withdrawal of niacinamide, skin color began to enter the “recovery period” (Figure ef), niacinamide inhibit melanin transport efficiency in the maintenance of a period of time began to appear a significant decline, until “back to its original form.
For the third group of data, I think there can be two interpretations, one is niacinamide inhibit melanin effect is reversible, the human body is safe, in turn, can also be understood as when you no longer use niacinamide, the skin is likely to appear “anti-black” situation. Usually a lot of small partners message about the use of whitening products after the emergence of anti-black, products are niacinamide?
(4) In addition to the whitening sector, the above three fresh meat, in fact, there is a king of ingredients – light glycyrrhizin, more worthy of expanding to share with you. Photoglycyrrhizin is an important component of licorice flavonoids, only exists in photoglycyrrhiza glabra, in the past has always had a “whitening gold” reputation, of course, also let a lot of formulation engineers to stay away from, it is really too expensive, 90% purity photoglycyrrhizin price of 210,000/kg or so, after more than 10 years of development of the industry, the price has been reduced, but its price is still too high, but the price is still too low. After more than 10 years of industry development, the price has decreased, but its price is still the whitening ingredients in the “ceiling”.
However, the price of glycyrrhizin in the field of whitening is a true reflection of the “expensive reason”. The biological activity of glycyrrhizin is related to its unique chemical structure. The entire structure can be divided into two major parts, the A ring for the isoflavone nucleus, the B ring for the resorcinol-like structure (like 377?).
The first major action of ①Light Licorice – Directly attacking the melanin (tyrosinase activity center). Our whitening action principle diagram shows 4 whitening steps, of which the core of whitening is the second step, inhibit the activity of melanocytes, find ways to stop the melanin factory – melanocytes “production” of melanin. This step is the most effective of the whitening pathways and is the angle that most whitening products on the market focus on. Inhibiting melanin cell ingredients, the most efficient than the resorcinol family of ingredients: phenylethylresorcinol (377), 4-butylresorcinol, hexylresorcinol; in fact, the light licorice, resveratrol, and these ingredients also have a high degree of similarity, also belongs to the resorcinol derivatives.
Light glycyrrhizin can be firmly stuck in the active center of tyrosinase, the synthesis of melanin is the most important machine stuck can not continue to run, less melanin, the skin will naturally white. At the same time, the structure of resorcinol also gives light glycyrrhizin powerful antioxidant ability, if VC is more outstanding ability is that it has the ability to restore melanin intermediates, then light glycyrrhizin is also not weak.
Let me show you another set of experiments with zebrafish:
Zebrafish is very suitable for whitening effect test, after hatching zebrafish close to transparent, melanin content is clearly visible, at the same time the development of small fish can also be a good reflection of whitening ingredients “toxicity”. The picture above is very clear, the development of each fish is very good, 4μM concentration of photoglycoside, the body is almost colorless, the effect of melanin inhibition is not a drop. In addition, compared with other resorcinol family components (such as 377), the cytotoxicity of glycyrrhizin can be said to be minimal.
② To be effective, but also to be safe; photoglycodine not only has strong performance, but also has low irritation to the skin. The structure of photoglycopyrrolidine can be distinguished into two parts: the flavonoid part and the resorcinol part; photoglycopyrrolidine has the structure of isoprenoid flavonoids, and its anti-inflammatory activity was confirmed as early as 1998, which significantly reduces the activity of peroxidase and the inflammatory mediators prostaglandin E2, NO, and pro-inflammatory cytokine production. At a concentration of 6.25 μg/mL, the activity of COX induced by the addition of arachidonic acid (AA) stimulation was inhibited by 31.9%.
The flavonoid portion of the structure of photoglycodine has anti-inflammatory and skin-conditioning properties; UVB-induced hyperpigmentation was induced by exposing guinea pigs to UV, and then applied with photoglycodine solution, which was found to reduce UVB-induced hyperpigmentation and erythema production.
Therefore, light glycyrrhizin can be said to be a set of super inhibition of tyrosinase activity (comparable to 377), strong antioxidant, low irritation in a whitening ingredient, high efficiency and gentle whitening, not easy to anti-black, more suitable for the skin quality of the Chinese people, the ingredients, if the price can be lowered, you can not love it?