Recent results on the oxidation of cysteine residues that bind zinc in transcription factors and their analogous peptides and in related proteins and model systems are reviewed. Two classes of oxidants, the transition metals and dioxygen, hydrogen peroxide, and related species, are considered, and the role of metal ions in suppressing or enhancing Cys oxidation is a major focus. Cysteines in the zinc-bound structures of transcription factors are less susceptible to oxidation than in the metal-free form, and this appears to correlate with reduced accessibility of the thiolates to oxidants. Substitution of other metal ions for Zn(II) increases the rate of Cys oxidation, apparently through increased oxidant accessibility. Reactions that result in reversible or irreversible oxidation of these zinc-binding cysteines under biological conditions are identified in the context of deleterious implications for gene expression.

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Removal of arsenic ion from fish condiment using lignin as adsorbent was investigated. The effects of pH of aquatic condiment solution, temperature, adsorption time, solid to liquid ratio, salt concentration and amino acid concentration on the removal ratio of arsenic ion from aquatic condiment were also studied. Removal ratio of arsenic ion reached 98.65% with pH 2, temperature 40 °C, adsorption time 25 min, solid to liquid ratio 1:70. It was confirmed that lignin can be used to remove arsenic ion from aquatic condiment.

Sulfhydryl lignin was prepared by immobilizing sulfhydryl onto wood lignin. The effect of pH, temperatμre, adsorption time, salinity of condiment and amino acid concentration of condiment on the adsorption behavior of sulfhydryl lignin was investigated, respectively. The adsorption kinetics and thermodynamics of Cu(Ⅱ) were also studied.

Using •OH scavenging test, an efficient method had been developed to acquire protein hydrolysate (MMH) from Mytilus coruscus by an orthogonal L9(34) test. The optimal enzymolysis parameters were enzymolysis time 3 h, temperature 60°C, solid-liquid ratio 1:2 and enzyme dose 3%. Enzymolysis temperature and solid-liquid ratio showed significant effects (ANOVA p<0.05) on the hydrolysate preparation. Based on the molecular weight (MW), MMH-I (10