[Objective] This study aims to screen for the high effective fungicides which could significantly decrease the disease incidence and disease index of rice false smut. [Method] The inhibitory activities of the fungicid...[Objective] This study aims to screen for the high effective fungicides which could significantly decrease the disease incidence and disease index of rice false smut. [Method] The inhibitory activities of the fungicide against mycelial growth of Ustilaginoidea virens were measured to in vitro evaluate the ECho values. And 17 fungicides were sprayed to evaluate the efficacy and effect of the fungicides tested in the field trials on the rice characters, [Result] The results showed that epoxicona- zole, difenoconazole, propiconazole and procloraz exhibited high inhibitory activity against mycelial growth of Ustilaginoidea virens with the ECso values 0.04, 0.07, 0.12 and 0.11 pg/ml, respectively. The results of field trials showed that the efficacy of Wen- quning, and fungicides such as difenoconazole, prochloraz, propiconazole, epoxi- conazole and their mixtures in controlling rice false smut were all 70% or more. [Conclusion] The 17 tested fungicides behaved efficacy in controlling rice false smut and did not cause drug injury on leaves and grains of rice plants, sprayed when flag leaves of rice fully expanded.展开更多
The gene encoding the 20S proteasome subunit（PR29） was cloned from cDNA library of Trichoderma harzianum and expressed in Escherichia coli BL21 （D3） using a pET-28a expression system. The molecular weight of the p...The gene encoding the 20S proteasome subunit（PR29） was cloned from cDNA library of Trichoderma harzianum and expressed in Escherichia coli BL21 （D3） using a pET-28a expression system. The molecular weight of the protein was found to be approximately 29 kDa, as estimated by SDS-PAGE on gels. The target protein was insoluble when induced at 22℃ with 0.4 mmol/L IPTG, while dissoluble if induced at 37℃ with 0.8mmoL/L IPTG. The expressed product was purified through Ni-magnetic beads His Bind. The purity of the fusion protein reached above 80%. The entire eDNA sequence consisted of 1094 bp with 173 and 135 bp in 5＇ and 3＇ untranslated regions respectively. The gene encoding 261 amino acids has no signal peptide sequence. These results could provide a basis for validating the func-tions of PR29. It also provided a preliminary indication for further study of the mechanism and function of proteasome, and more information of proteasome mechanism in T.harzianum could be obtained.展开更多
After deregulating the purine and riboflavin synthesis in the Gram-positive bacterium Bacillus subtilis,it is critical to amplify riboflavin operon with appropriate dosage in the host strain for remarkable increase of...After deregulating the purine and riboflavin synthesis in the Gram-positive bacterium Bacillus subtilis,it is critical to amplify riboflavin operon with appropriate dosage in the host strain for remarkable increase of riboflavin production.Bacillus subtilis RH13, a riboflavin-producing strain, was selected as host strain in the construction of engineering strains by protoplast fusion. The integrative plasmid pRB63 and autonomous plasmid pRB49, pRB62 containing riboflavin operon of B.subtilis 24 were constructed and transformed into the host strain respectively. Increasing one operon copy in B.subtilis RH13 results in about 0.4 g/L improvement in riboflavin yield and the appropriate number of operon copies was about 7—8. Amplifying more riboflavin operons is of no use for further improvement of yield of riboflavin. Furthermore, excessive operon dosage results in metabolic unbalance and is fatal to the host cells producing riboflavin.展开更多
Microbial flocculants have become a hot spot in recent years. A bacterial strain with high flocculating activity was isolated from seawater samples. The strain was defined as Bacillus licheniformis dhs-40 by 16S rDNA ...Microbial flocculants have become a hot spot in recent years. A bacterial strain with high flocculating activity was isolated from seawater samples. The strain was defined as Bacillus licheniformis dhs-40 by 16S rDNA identification and Biolog test. Ultrasonication test confirmed the flocculating activity of the strain was both in fermentation supernatant and cell. According to flocculating activity curve, the ideal fermentation time for collecting flocculating active substances was two days. The flocculating activity of the strain was sensitive to pH. The strain could only preserve flocculating activity while pH varied from 7 to 11. However, it could preserve flocculating activity while temperature varied from -20℃to 100 ℃ Saccharide, protein, lipid, nucleic acids qualitative test and RNase, Proteinase K treatment confirmed the flocculating active substances were proteins. Their flocculating activities were insensitive to Proteinase K.展开更多
The Brazilian＇s interest in the nuclear utilization of thorium has started in the 1950s as a consequence of the abundant occurrence ofmonazite sands. Since the 1960s, IPEN-CNEN/SP （lnstituto de Pesquisas Energ6ticas...The Brazilian＇s interest in the nuclear utilization of thorium has started in the 1950s as a consequence of the abundant occurrence ofmonazite sands. Since the 1960s, IPEN-CNEN/SP （lnstituto de Pesquisas Energ6ticas e Nucleares） has performed some developments related to the thorium fuel cycle. The production and purification of thorium compounds was carried out at IPEN for about 18 years and the main product was the thorium nitrate with high purity, having been produced over 170 metric tons of this material in the period, obtained through solvent extraction. The thorium nitrate was supplied to the domestic industry and used for gas portable lamps （Welsbach mantle）. Although the thorium compounds produced have not been employed in the nuclear area, several studies were conducted. Therefore, those activities and the accumulated experience are of strategic importance, on one hand, due to huge Brazilian thorium reserves, on the other hand, by the resurgence of the interest of thorium for the Generation IV advanced reactors. This paper presents a review of the Brazilian research and development activities related to thorium technology.展开更多
The discovery of the novel reactivity of conjugated enynes,mediated by readily available halogenation reagents,opens a broad range of mechanistically unique pathways for the synthesis of highly functionalized chiral a...The discovery of the novel reactivity of conjugated enynes,mediated by readily available halogenation reagents,opens a broad range of mechanistically unique pathways for the synthesis of highly functionalized chiral allene derivatives.Bromoallenyl pyrrolidines can be synthesized via 1,4-addition of sulfonamide nitrogen nucleophiles and halogens to conjugated enynes.This process can lead to simultaneous formation of a highly functionalized axially chiral allene and a stereogenic center under economical and environmentally friendly reaction conditions.展开更多
基金Supported by Agricultural S&T Innovation:Genetic Structure Analysis and Parasitism Fitness of U.virens in Anhui Province(14B1148)Special Fund for Talent Development:Pesticide Innovation and High-efficient Application Technology(13C1109)~~
文摘[Objective] This study aims to screen for the high effective fungicides which could significantly decrease the disease incidence and disease index of rice false smut. [Method] The inhibitory activities of the fungicide against mycelial growth of Ustilaginoidea virens were measured to in vitro evaluate the ECho values. And 17 fungicides were sprayed to evaluate the efficacy and effect of the fungicides tested in the field trials on the rice characters, [Result] The results showed that epoxicona- zole, difenoconazole, propiconazole and procloraz exhibited high inhibitory activity against mycelial growth of Ustilaginoidea virens with the ECso values 0.04, 0.07, 0.12 and 0.11 pg/ml, respectively. The results of field trials showed that the efficacy of Wen- quning, and fungicides such as difenoconazole, prochloraz, propiconazole, epoxi- conazole and their mixtures in controlling rice false smut were all 70% or more. [Conclusion] The 17 tested fungicides behaved efficacy in controlling rice false smut and did not cause drug injury on leaves and grains of rice plants, sprayed when flag leaves of rice fully expanded.
文摘The gene encoding the 20S proteasome subunit（PR29） was cloned from cDNA library of Trichoderma harzianum and expressed in Escherichia coli BL21 （D3） using a pET-28a expression system. The molecular weight of the protein was found to be approximately 29 kDa, as estimated by SDS-PAGE on gels. The target protein was insoluble when induced at 22℃ with 0.4 mmol/L IPTG, while dissoluble if induced at 37℃ with 0.8mmoL/L IPTG. The expressed product was purified through Ni-magnetic beads His Bind. The purity of the fusion protein reached above 80%. The entire eDNA sequence consisted of 1094 bp with 173 and 135 bp in 5＇ and 3＇ untranslated regions respectively. The gene encoding 261 amino acids has no signal peptide sequence. These results could provide a basis for validating the func-tions of PR29. It also provided a preliminary indication for further study of the mechanism and function of proteasome, and more information of proteasome mechanism in T.harzianum could be obtained.
文摘After deregulating the purine and riboflavin synthesis in the Gram-positive bacterium Bacillus subtilis,it is critical to amplify riboflavin operon with appropriate dosage in the host strain for remarkable increase of riboflavin production.Bacillus subtilis RH13, a riboflavin-producing strain, was selected as host strain in the construction of engineering strains by protoplast fusion. The integrative plasmid pRB63 and autonomous plasmid pRB49, pRB62 containing riboflavin operon of B.subtilis 24 were constructed and transformed into the host strain respectively. Increasing one operon copy in B.subtilis RH13 results in about 0.4 g/L improvement in riboflavin yield and the appropriate number of operon copies was about 7—8. Amplifying more riboflavin operons is of no use for further improvement of yield of riboflavin. Furthermore, excessive operon dosage results in metabolic unbalance and is fatal to the host cells producing riboflavin.
文摘Microbial flocculants have become a hot spot in recent years. A bacterial strain with high flocculating activity was isolated from seawater samples. The strain was defined as Bacillus licheniformis dhs-40 by 16S rDNA identification and Biolog test. Ultrasonication test confirmed the flocculating activity of the strain was both in fermentation supernatant and cell. According to flocculating activity curve, the ideal fermentation time for collecting flocculating active substances was two days. The flocculating activity of the strain was sensitive to pH. The strain could only preserve flocculating activity while pH varied from 7 to 11. However, it could preserve flocculating activity while temperature varied from -20℃to 100 ℃ Saccharide, protein, lipid, nucleic acids qualitative test and RNase, Proteinase K treatment confirmed the flocculating active substances were proteins. Their flocculating activities were insensitive to Proteinase K.
文摘The Brazilian＇s interest in the nuclear utilization of thorium has started in the 1950s as a consequence of the abundant occurrence ofmonazite sands. Since the 1960s, IPEN-CNEN/SP （lnstituto de Pesquisas Energ6ticas e Nucleares） has performed some developments related to the thorium fuel cycle. The production and purification of thorium compounds was carried out at IPEN for about 18 years and the main product was the thorium nitrate with high purity, having been produced over 170 metric tons of this material in the period, obtained through solvent extraction. The thorium nitrate was supplied to the domestic industry and used for gas portable lamps （Welsbach mantle）. Although the thorium compounds produced have not been employed in the nuclear area, several studies were conducted. Therefore, those activities and the accumulated experience are of strategic importance, on one hand, due to huge Brazilian thorium reserves, on the other hand, by the resurgence of the interest of thorium for the Generation IV advanced reactors. This paper presents a review of the Brazilian research and development activities related to thorium technology.
基金the University of Wisconsin-Madison and the American Chemical Society Petroleum Research Fund (48092-G) for funding
文摘The discovery of the novel reactivity of conjugated enynes,mediated by readily available halogenation reagents,opens a broad range of mechanistically unique pathways for the synthesis of highly functionalized chiral allene derivatives.Bromoallenyl pyrrolidines can be synthesized via 1,4-addition of sulfonamide nitrogen nucleophiles and halogens to conjugated enynes.This process can lead to simultaneous formation of a highly functionalized axially chiral allene and a stereogenic center under economical and environmentally friendly reaction conditions.
