The mysterious chemical in Cowherb Seed which is responsible for skin whitening
Alina Ziqian Qiu
Magee Secondary
Floor Location : S 064 D

Cowherb seed is well known as an excellent Chinese herb to promote diuresis and milk secretion, activate blood circulation and relieve swelling. Inspired by an online post of a secret prescription about removing skin spot by using cowherb seed, I did researches on cowherb seed and designed an experiment to show whether cowherb seed truly can help to whiten skin since no published articles have ever revealed the whiten function of cowherb seed. The experiment results showed that both water extract and ethanol extract of cowherb seed have inhibitory effect on tyrosine-tyrosinase reaction which is involved in the synthesis of pigment melanin, and their inhibitory rates are very similar and have no significant difference.
Further chemical analysis experiments (HPLC, Infrared Spectrum, Hydrogen Emission Spectrum, C-13 NMR Spectrum, and Mass Spcetrum) revealed that vaccarin (C32H38O19) that exists in both water and ethanol extract of cowherb seed is most likely to have the main contribution to the inhibitory effect of cowherb seed on tyrosine-tyrosinase reaction. Four different concentrations of vaccarin (800uM, 400uM, 200uM, and 100uM) have been tested; however, the correlation between the concentration of vaccarin and the inhibitory rate has not been detected. All four concentrations of vaccarin showed 29% to 31% inhibitory percentage to tyrosine-tyrosinase reaction, and there is no significant difference among the inhibitory percentages associated with different concentration of vaccarin.
Therefore, vaccarin does have inhibitory effect on tyrosine-tyrosinase reaction, but the inhibitory effect may not depend on the concentration of vaccarin. In order for vaccarin to be used as an alternative treatment for hyperpigmentation, cell test needs to be performed to check if there is any toxic effect resulted from vaccarin to human cells.