教師著作

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    Protective effect of spices against peroxynitrite.
    (2006-10-28) Po-Jung Tsai, Wan-Ju Lu, Hua-Wen Liang, and Su-Chen Ho
    Peroxynitrite, a potent cytotoxic agent, can damage a variety of biomolecules such as proteins, lipids, and DNA, is considered as the major pathological factor in several disease states. Due to the cells lack a specific enzyme to decompose peroxynitrite, the burden of defense against peroxynitrite relies solely on nonezymatic antioxidants. Therefore, it would appear likely that interception of peroxynitrite by certain food items would serve as a promising indicator for the beneficial "health effects" of such food. Spices, rich in phenolics, are speculated conceivably to act as potential peroxynitrite scavengers. The protective effects of methanol extracts derived from eight culinary spices against peroxynitrite mediated damages on proteins, lipids and DNA were determined. All of the tested spices exerted protective effect against peroxynitrite mediated tyrosine nitration, lipid peroxidation and DNA strand breakage. Cloves displayed the most excellent protection. Moreover, phenolics content of spice was highly correlated with their protective effect against peroxynitrite mediated tyrosine nitration and lipid peroxidation. These results indicated that the protective effects of spices against peroxynitrite mediated bimolecule damages were attributed to the phenolics.
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    Physiochemical, antioxidant and whitening properties of extract from root cortices of mulberry as affected by membrane
    (Elsevier, 2007-06-01) Yu, Z.-R., Hung, C.-C., Weng, Y.-M., Su, C.-L., and Wang, B.-J.,
    Extract from root cortices of mulberry (Morus alba, L.) was separated into permeate and retentate fractions using a membrane system equipped with either a microfiltration membrane or one of four molecular weight cut-off ultrafiltration membranes. The effects of membrane process at volume concentration ratio (VCR)=4 on the physiochemical characteristics, the contents of active compounds, antioxidant ability, and whitening capability (tyrosinase inhibitory activity) in permeate and retentate were evaluated. The clarification degree, antioxidant effects, and whitening capability of the permeates increased as compared to those of feed. In addition, permeate treated with a 0.45 μm microfiltration membrane exhibited less fouling layer and specific resistance (αpCB=622.8 m−2×10−6) and thus had a higher permeate flux than treated with other ultrafiltration membranes (αpCB=786.1–1025.3 m−2×10−6). A higher content of active compounds, such as chlorogenoic acid and p-hydroxybenzoic acid may explain higher antioxidant and whitening capabilities in permeate of extracts from root cortices of mulberry.