ANTIOXIDANTS IN MUNG BEAN SPROUTS AND SAFETY FOR COSMETIC USE 209 extract will precipitate under acidic conditions (pH = 3.0–5.0), which cause a decrease in antioxidant activity. In neutral or acidic conditions, polyphenols has better activity and stability. Therefore, the suitable pH condition of mung bean sprouts extract is between 6 and 7, and our research is working on this condition. Results of 1,1-diphenyl-2-picrylhydrazyl radical scavenging. The antioxidizing capacities of mung bean sprout extracts (total soluble solid content: 200 mg/ml) are shown in Figure 3. Rates of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging of mung bean ex- tracts (200 mg/ml) between 0 and 8 days after germination were all greater than 85%, close to the activity of vitamin C. Compared with mung bean seeds, extracts of sprouts had higher DPPH radical scavenging capacity. An alysis of variance showed signifi cant differences in the antioxidant activity between seeds and sprouts, indicating that bud length did infl uence the antioxidant activity, possibly because the budding process Figure 2. Concentration (mg/ml) of proteins in mung bean sprouts germinated from 0 to 8 days (n = 3). Figure 3. DPPH radical scavenging rates (%) of extracts obtained from different germination times of mung bean sprouts (n = 3).

JOURNAL OF COSMETIC SCIENCE 210 increases the antioxidizing activity of certain smaller components. So, sprout extracts have good potential for use in food and cosmetic products as a new antioxidant, which is natural, pro-environment, and the production process relatively much simpler. Results of total antioxidant capacity. The experiment measuring the standard curve is y = 0.23x + 0.0101 (R2 = 0.9886, x: concentration of FeSO4 (mM) y:absorption value). The total antioxidant capacity of mung bean extracts (200 mg/ml) from 0 to 8 days after ger- mination was examined by the ferric reducing antioxidant power (FRAP) method. The total antioxidant capacity of mung bean extracts (200 mg/ml) from days 0 to 8 was examined by aFRAP test. As Figure 4 shows, the total antioxidant capacities of the ex- tracts from 2 and 6 days after germination are the highest, about 7.47 mmol/kg. The total antioxidant capacity of the samples from other days are lower than these two days, but compared with mung bean seed, mung bean sprouts have higher total antioxidant capacity. The FRAP assay showed that extracts from 2 and 6 days after germination had a high ferric reducing antioxidant capacity. We also observed a positive and signifi cant correla- tion between the concentrations of polyphenols in water extracts of mung bean sprouts and FRAP results (R2 = 0.989 and p = 0.020). As section on “Concentrations of Polyphe- nols and Proteins in Extracts” shows, the concentrations of polyphenols 2–3 days and 6–7 days after germination are higher than that on the other days. A correlation observed between FRAP and the concentrations of polyphenols in mung bean sprouts was also re- ported by Huang et al. (11), owing to the ability of polyphenols to act as hydrogen donors. Results of chelation abilities of ferrous ion. C helation abilities of ferrous ion of mung bean extracts (200 mg/ml) from 0 to 8 days after germination are shown in Figure 5. Antioxidants can quench reactive oxygen, accept free radicals, or chelate metal ions. Through these and other various ways of preventing free radical chain reactions, they can eliminate damage to the organism by the oxidation of the material, such as lipid peroxidation. Therefore, the chelating ability of Fe(II) is also commonly used to evaluate Figure 4. Total antioxidant capacity (mmol/kg) of extracts obtained from different germination times of mung bean sprouts (n = 3).