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The purpose of this research was to investigate how university students' nutrition beliefs influence their health behavioral intention. This study used an online survey engine (Qulatrics.com) to collect data from college students. Out of 253 questionnaires collected, 251 questionnaires (99.2%) were used for the statistical analysis. Confirmatory Factor Analysis (CFA) revealed that six dimensions, "Nutrition Confidence," "Susceptibility," "Severity," "Barrier," "Benefit," "Behavioral Intention to Eat Healthy Food," and "Behavioral Intention to do Physical Activity," had construct validity; Cronbach's alpha coefficient and composite reliabilities were tested for item reliability. The results validate that objective nutrition knowledge was a good predictor of college students' nutrition confidence. The results also clearly showed that two direct measures were significant predictors of behavioral intentions as hypothesized. Perceived benefit of eating healthy food and perceived barrier for eat healthy food to had significant effects on Behavioral Intentions and was a valid measurement to use to determine Behavioral Intentions. These findings can enhance the extant literature on the universal applicability of the model and serve as useful references for further investigations of the validity of the model within other health care or foodservice settings and for other health behavioral categories.

Peroxynitrite is a cytotoxic intermediate produced by the reaction between a superoxide anion radical and nitric oxide. The scavenging activities of flavonoids on peroxynitrite were investigated to illustrate the structure-activity relationship. Peroxynitrite was scavenged by the presence of various flavonoids, whose structures seem to be closely related to the degree of scavenging. Of 31 compounds tested, the most active was quercetin, with an IC50 value of 0.93 microM. Others had IC50 values ranging from 0.96 to more than 10 microM. The scavenging activity was postulated to be governed by the position of the hydroxyl group. Ortho-hydroxyl structures increased the scavenging activity on peroxynitrite.

Tyrosinase (monophenol, dihydroxy-L-phenylalanin: oxygen oxidoreductase, EC 1.14.18.1) is a copper-dependent protein widely distributed in nature.2) The enzyme catalyzes two different reactions: the hydroxylation of monophenols to o-diphenols (monophenolase activity) and the oxidation of odiphenols to o-quinones (diphenolase activity), both utilizing molecular oxygen.3)The enzymatic browning of fruits and vegetables is mostly related to the oxidation of endogenous phenolic containing compounds catalyzed by polyphenol oxidase. 4) Tyrosinase also is responsible for melanization in animals, and is the key enzyme for the regulation of melanogenesis in mammals. 5)Melanin is synthesized in epidermal melanocytes, and then is transferred into epidermal keratinocytes via the melanocytes' dendrites. 6) Melanogenesis is the process by which melanin is produced (and subsequently distributed) by melanocytes within the skin and hair follicles.7) This process results in the synthesis of melanin pigments, which plays a protective role against skin photocarsinogenesis.8) The main physiological stimulus of melanogenesis is the ultraviolet radiation of solar light, which can act directly on melanocytes or indirectly through the release of keratinocyte-derived factors such as MSH (a-melanocyte stimulating hormone). 9)One of the biggest causative agents of hyperpigmentaion is probably UV light. 10) However, skin darkening can be suppressed, at least partially, by deactivating of tyrosinase. 11)Therefore, tyrosinase inhibitors have become increasingly important in the cosmetic and medicinal products used in the prevention of hyperpigmentaion.12) Many compounds, such as hydroquinone, 13) kojic acid, 14) and benzaldehyde-O-alkyloximes 15) have been reported as tyrosinase inhibitors. The established murine B16F10 melanoma cell (B16 cells) line offers a model system with readily quantifiable markers that are characteristic of differentiating, including melanogenesis. 16) In B16 cells, a-tocopheryl ferulate was shown to have depigmenting effect. 17) Although 4,4Ј-dihydroxybiphenyl (44Ј-BP), a bisphenol derivative was known as a radical scavenger for methacrylate polymerization, 18) but its efficacy on tyrosinase inhibition and melanin biosynthesis has not been reported.The aim of this study was to characterize inhibition mode of 44Ј-BP on mushroom tyrosinase. We also examined the inhibitory effect of 44Ј-BP on melanin biosynthesis, and cell viability in B16 cells as a biomarker for the potential cytotoxicity. Cell Culture B16 cells (from Korean Cell Line Bank) were cultured in DMEM with 10% fetal bovine serum (FBS; Gibco) and penicillin/streptomycin (100 IU/50 mg/ml) in a humidified atmosphere containing 5% CO 2 in air at 37°C. B16 cells were cultured in 24-well plates for the melanin quantification and enzyme activity assays. MATERIALS AND METHODS MaterialsDetermination of 44-BP for Cell Viability The cell proliferation assay was carried out by the method of Tada et al. using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (...

Peroxynitrite formed from superoxide and nitric oxide acts as a strong reactive oxidant. However, among green tea components, catechins with a galloyl group inhibited peroxynitrite formation by 3-morpholinosydnonimine and scavenged peroxynitrite itself. Especially when compared with penicillamine as a positive control, the green tea components (−)-epigallocatechin 3-O-gallate and (−)-gallocatechin 3-O-gallate, which have two galloyl groups, showed the most potent peroxynitrite-scavenging activity, indicating that the galloyl group may contribute to this activity. A structure of flavan-3-ol linked to gallic acid may be essential for the peroxynitrite-scavenging activity. Keywords: (−)-Epigallocatechin 3-O-gallate; (−)-gallocatechin 3-O-gallate; green tea; peroxynitrite

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