The effects of aluminum on ATPase activity and lipid composition of the plasma membranes isolated from root tips of Al-tolerant (Altas 66) or Al-sensitive (Scout 66) cultivar of Triticum aestivum L. was assayed. The r...The effects of aluminum on ATPase activity and lipid composition of the plasma membranes isolated from root tips of Al-tolerant (Altas 66) or Al-sensitive (Scout 66) cultivar of Triticum aestivum L. was assayed. The results showed that both cultivars had similar changes in H+-ATPase and Ca2+-ATPase activities after aluminum treatment. Exposure of both cultivars to 20 and 100 (mol/L aluminum for 5 d significantly decreased the activities of Ca2 + -ATPase of plasma membranes. The activities of H+-ATPase in plasma membrane increased under 20 μmol/L aluminum and decreased at 100 u.mol/L aluminum. With aluminum treatment, the PL content of plasma membrane decreased, but GL content increased. The ratio of PL to GL decreased more distinctly in Scout 66 than that in Altas 66. Treated with 20 and 100 μmol/L aluminum, linolenic acid content and the index of unsaturated fatty acids decreaced greatly in Scout 66, but the index of unsaturated fatty acids in Altas 66 increased slightly.展开更多
The variations of muscle tissus, peroxidase and Ca2+-ATPase activities and Vp （pasteurization value） were investigated with the fresh samples of grass carp （Ctenopharyngodon idellus） heated at different temperatur...The variations of muscle tissus, peroxidase and Ca2+-ATPase activities and Vp （pasteurization value） were investigated with the fresh samples of grass carp （Ctenopharyngodon idellus） heated at different temperatures, thus revealing the mechanism of denaturation of muscle protein by heating. The experimental results showed the great difference in muscle tissue structure before and after the samples heated. In the initial stage of heating the water loss accounted for 50% of the total. When the samples were separately heated at 75, 85, and 95℃, fh values （dehydration curve slope） were 5, 4.1 and 1.7, respectively, while Vp reaching 40 minutes were 22, 8 and 5 min, respectively. As to the time for deactivation of peroxidase in the heated samples at the various temperatures, it varied from 38, 10 and to less than 6 min, respectively and the deactivation rates of Ca2+-ATPase in 1 min were 50%, 88% and 100%, respectively. Consequently, the higher temperature the sample was heated, the faster rate of thermocon ductivity, the lower rate of water loss, and the faster rate of peroxidase deactivation it was. Also, the Vp for the least requirement of pasteurization （Vp≥40min） was obtained.展开更多
基金supported by the National Natural Science Foundation of China(0070448).
文摘The effects of aluminum on ATPase activity and lipid composition of the plasma membranes isolated from root tips of Al-tolerant (Altas 66) or Al-sensitive (Scout 66) cultivar of Triticum aestivum L. was assayed. The results showed that both cultivars had similar changes in H+-ATPase and Ca2+-ATPase activities after aluminum treatment. Exposure of both cultivars to 20 and 100 (mol/L aluminum for 5 d significantly decreased the activities of Ca2 + -ATPase of plasma membranes. The activities of H+-ATPase in plasma membrane increased under 20 μmol/L aluminum and decreased at 100 u.mol/L aluminum. With aluminum treatment, the PL content of plasma membrane decreased, but GL content increased. The ratio of PL to GL decreased more distinctly in Scout 66 than that in Altas 66. Treated with 20 and 100 μmol/L aluminum, linolenic acid content and the index of unsaturated fatty acids decreaced greatly in Scout 66, but the index of unsaturated fatty acids in Altas 66 increased slightly.
文摘The variations of muscle tissus, peroxidase and Ca2+-ATPase activities and Vp （pasteurization value） were investigated with the fresh samples of grass carp （Ctenopharyngodon idellus） heated at different temperatures, thus revealing the mechanism of denaturation of muscle protein by heating. The experimental results showed the great difference in muscle tissue structure before and after the samples heated. In the initial stage of heating the water loss accounted for 50% of the total. When the samples were separately heated at 75, 85, and 95℃, fh values （dehydration curve slope） were 5, 4.1 and 1.7, respectively, while Vp reaching 40 minutes were 22, 8 and 5 min, respectively. As to the time for deactivation of peroxidase in the heated samples at the various temperatures, it varied from 38, 10 and to less than 6 min, respectively and the deactivation rates of Ca2+-ATPase in 1 min were 50%, 88% and 100%, respectively. Consequently, the higher temperature the sample was heated, the faster rate of thermocon ductivity, the lower rate of water loss, and the faster rate of peroxidase deactivation it was. Also, the Vp for the least requirement of pasteurization （Vp≥40min） was obtained.
