Drinks for Skin Whitening 美白好容「薏」 AbstractAbstract

Whitening creams and bleaching products are widely used as a popular beauty treatment in

many parts of the world. Some people think women with light skin are the most beautiful.

This beauty standard pushes many girls to de-pigment their skin. However, recent medical re-

search reveals that some skin-whitening products can cause long-term health problems. Skin

cancer is believed to be a side effect of the products, citing other health complications including

high blood pressure and diabetes. Therefore, our study would like to explore some natural

drinks, substituting the cosmetic products for skin whitening.

Methodology and ResultsMethodology and Results

Coix chinensis (small grain) Almond milk Soy milk Ascorbic Acid Coix chinensis (large grain)

A standard curve for the UV absorb-

ance of melanin

Melanin concentration was measured in terms of UV

absorbance in the following tests.

Squid ink was collected from

the ink sac of squid. Squid ink

is blackened by melanin, the

same chemical constituent as

human skin pigment. Therefore,

squid ink was used to simulate

pigmentation of human skin.

◆ The squid ink was diluted to different concentrations and the UV absorbance of each sample was examined under UV 360.

*** Melanin concentration = UV absorbance

4.7114

***

Test for the Bleaching effect

The bleaching effect of samples was tested to find

out if they could be applied directly on skin to remove

the black pigment.

◆ A block heater was used to keep a constant tempera-ture (left) and a student was using spectrophotometer to measure the UV absorbance of samples.

Squid ink: No Significant Change

Bacillus thuringuensis: Significant increment

Melanin could not be broke down by the tested sample,

i.e. no bleaching effect;

Any change in melanin concentration in the bacterial cul-

ture was due to the presence of Bacillus thuringuensis.

Test for inhibitory effect on melanin

synthesis

Bacillus thuringiensis was used as a living cell model

to simulate the human skin cell as it is able to produce

melanin during sporulation which was triggered under

adverse condition.

◆ Bt was incubated at 46°C with samples and the cell

mass was then removed by centrifugation at 6000 r.p.m. for 15 min. The concentration of the pigment was measured in a spectrophotometer at 360 nm

Melanin concentration

level below:

Inhibitory effect

◆ Bacillus thuringiensis

growing on Petri films.

◆ Pellet containing bacte-

rial cell mass were dif-ferent in sizes after centrifugation.

Deliverables and conclusive remarks Deliverables and conclusive remarks

◆ No samples demonstrated bleaching effect

◆ Skin whitening effect of Coix chinensis and ascorbic acid was preliminarily

proven in this study. They may probably contain antioxidant which intervene

melanin synthesis in cells.

◆ In-vivo test using human cell culture hence should be the future way of the in-

vestigation Skin Whitening Drink: Pearl Barley Lemon Water Home-made cost: HKD$5