The activity of lignin peroxidase (LiP) in reversed micelles of polyoxyethylene lauryl ether (Brij30) changed with the molar ratio of water to the surfactant and the denaturant concentration of guanidinium chloride. A...The activity of lignin peroxidase (LiP) in reversed micelles of polyoxyethylene lauryl ether (Brij30) changed with the molar ratio of water to the surfactant and the denaturant concentration of guanidinium chloride. At low water contents the activity of LiP could be enhanced by the denaturant at moderate concentration. This phenomenon, together with the spectral characteristics of the intrinsic fluorescence of LiP, suggested that the conformation of the active center of LiP was flexible.展开更多
The inhibition of ligninase by hydrogen peroxide in the presence of cationic surfactant CTAB was studied by kinetic spectrophotometric technique. Results showed that addition of CTAB enhanced the inhibition by H2O2, b...The inhibition of ligninase by hydrogen peroxide in the presence of cationic surfactant CTAB was studied by kinetic spectrophotometric technique. Results showed that addition of CTAB enhanced the inhibition by H2O2, but it did not alter the inhibition pattern and the inhibition constant changed little with the concentration of CTAB. Modification of the enzymic protein by the surfactant monomer may be responsible for the above mentioned results.展开更多
Epoxide hydrolase-catalyzed resolution of ethyl 3-phenylglydidate was investigated using resting cells of Pseudomonas sp. BZS21. Under the present conditions 26.2 % of (2R, 3S)- ethyl 3-phenylglycidate with ee value o...Epoxide hydrolase-catalyzed resolution of ethyl 3-phenylglydidate was investigated using resting cells of Pseudomonas sp. BZS21. Under the present conditions 26.2 % of (2R, 3S)- ethyl 3-phenylglycidate with ee value of 94.6 % was obtained from the racemic mixture.展开更多
Wheat straw was cut into a certain size range and treated with a strain of the white rot fungus Phanerochatete Chrysosporium for 5 days before subjected to a chemi-mechanical treatment. Chemical analyses revealed the ...Wheat straw was cut into a certain size range and treated with a strain of the white rot fungus Phanerochatete Chrysosporium for 5 days before subjected to a chemi-mechanical treatment. Chemical analyses revealed the effects of the white rot fungus on the wheat straw components. SEM was applied to observe the changes in fiber micromorphological structures. CODcr of the effluent from the sulfonation treatment of wheat straw was also discussed. Handsheets made from the treated and untreated wheat straw exhibited different optical and physical properties after chemi-mechanical pulping.展开更多
Wheat straw chemi-mechanical pulp was pretreated with a crude xylanase which was secreted by white rot fungus Phanerochaete Chrysosporium prior to hydrogen peroxide bleaching. The process of xylanase pretreatment and ...Wheat straw chemi-mechanical pulp was pretreated with a crude xylanase which was secreted by white rot fungus Phanerochaete Chrysosporium prior to hydrogen peroxide bleaching. The process of xylanase pretreatment and hydrogen peroxide bleaching was optimized. The xylanase treated pulp achieved a brightness gain of 5.8% ISO over the untreated pulp. The xylanase treatment was found to liberate reducing sugars and facilitating lignin removal. Fiber morphology of pulp treated with xylanase was also studied by SEM.展开更多
基金support from the National Natural Science Foundation of China(No.30470048)the Interdisciplinary Foundation of Shandong University
文摘The activity of lignin peroxidase (LiP) in reversed micelles of polyoxyethylene lauryl ether (Brij30) changed with the molar ratio of water to the surfactant and the denaturant concentration of guanidinium chloride. At low water contents the activity of LiP could be enhanced by the denaturant at moderate concentration. This phenomenon, together with the spectral characteristics of the intrinsic fluorescence of LiP, suggested that the conformation of the active center of LiP was flexible.
基金The authors gratefully acknowledge the financial support from the Natural Science Foundation of Shandong(Y2000D11)the National Natural Science Foundation of China(29906005).
文摘The inhibition of ligninase by hydrogen peroxide in the presence of cationic surfactant CTAB was studied by kinetic spectrophotometric technique. Results showed that addition of CTAB enhanced the inhibition by H2O2, but it did not alter the inhibition pattern and the inhibition constant changed little with the concentration of CTAB. Modification of the enzymic protein by the surfactant monomer may be responsible for the above mentioned results.
基金supported by the Natural Science Foundation of Shandong Province(No.Y2000C21)the National Natural Science Foundation of China(No.30270047).
文摘Epoxide hydrolase-catalyzed resolution of ethyl 3-phenylglydidate was investigated using resting cells of Pseudomonas sp. BZS21. Under the present conditions 26.2 % of (2R, 3S)- ethyl 3-phenylglycidate with ee value of 94.6 % was obtained from the racemic mixture.
文摘Wheat straw was cut into a certain size range and treated with a strain of the white rot fungus Phanerochatete Chrysosporium for 5 days before subjected to a chemi-mechanical treatment. Chemical analyses revealed the effects of the white rot fungus on the wheat straw components. SEM was applied to observe the changes in fiber micromorphological structures. CODcr of the effluent from the sulfonation treatment of wheat straw was also discussed. Handsheets made from the treated and untreated wheat straw exhibited different optical and physical properties after chemi-mechanical pulping.
文摘Wheat straw chemi-mechanical pulp was pretreated with a crude xylanase which was secreted by white rot fungus Phanerochaete Chrysosporium prior to hydrogen peroxide bleaching. The process of xylanase pretreatment and hydrogen peroxide bleaching was optimized. The xylanase treated pulp achieved a brightness gain of 5.8% ISO over the untreated pulp. The xylanase treatment was found to liberate reducing sugars and facilitating lignin removal. Fiber morphology of pulp treated with xylanase was also studied by SEM.
