ANTIOXIDANTS IN MUNG BEAN SPROUTS AND SAFETY FOR COSMETIC USE 211 antioxidant oxidation resistance. Antioxidant capacity is proportional to chelating ability (12). The ability of mung bean sprout extracts (200 mg/ml) obtained 0–8 days after germina- tion to chelate ferrous ions was examined using ferrozine. Compared with mung bean seeds, mung bean fi rst-day sprouts have higher chelation capacity. The chelation abilities of the fi rst-day extract is the highest, which is nearly 80%, probably because antioxidants are activated in the initial germination process, which enhances the inducing activity of the related enzymes (13). However, the chelation abilities of mung bean extracts de- creased noticeably during the process of germination. A possible cause is that the activity of the antioxidant was suppressed in the later period of budding. SAFETY Results of red blood cell test. At different postgermination times, we did the red blood cell (RBC) test, the results of which are shown in Figure 6. The rates of hemolysis of mung bean sprout extract for 0–8 days after germination were all lower than 10%, less than the 20% excitant limit according to current regulations. Results showed that the extracts from mung bean sprouts without stimulation can be used as potential cosmetic additives. Results of the chorioallantoic membrane assay. The chorioallantoic membrane (CAM) assay results are shown in Figure 7, where the chick embryos of the positive control groups all died after 48 h while the embryos of the sample groups all survived. Morphological observation results show that in the sample groups, there were no hyper- emia or exudation in capillary ending, no visual change of capillary network, no change of vessel, and morphological structure was clear. Compared with the negative control group, mung bean sprout extracts were safe without irritation. Figure 5. Chelation abilities of ferrous ion rates (%) of extracts obtained from different germination times of mung bean sprouts (n = 3).

JOURNAL OF COSMETIC SCIENCE 212 Human skin patch test results. The results of the human skin patch test are shown in Table I. Results show that no change, even light erythema, was observed on the skin of those 32 subjects, indicating that mung bean sprout extracts from 0 to 8 days after germination are safe to human skin. In conclusion, all safety evaluation results mentioned above indicate that the mung bean sprout extracts are safe to use in products intended for application on human skin. EXPERIMENTAL REAGENTS AND MATERIALS Mung beans (V.radiatus L.) (Beijing, China) DPPH radical, Folin–Ciocalteu reagent, AR (Sigma-Aldrich Co., Ltd, St. Louis, MO) and Coomassie Brilliant Blue, AR (Biodee Figure 6. Hemolysis ratios during different periods of mung bean sprout. Figure 7. Photographs from CAM assay taken during vascular morphological observation of chick embryos: (A) negative control (0.9% normal saline), no hyperemia, no exudation, clear morphological structure and profi le (B) positive control (0.4% SDS), obvious hyperemia, obvious fading, hemoglobin degeneration (C) mung bean sprout extract (10 mg/ml), slight hyperemia, no exudation, clear morphological structure and profi le, no change.