Potato common scab(CS)is a worldwide disease,caused by Streptomyces spp.,and its presence reduces the market value of potatoes.A nontoxic and potentially effective approach in many control strategies is the use of ant...Potato common scab(CS)is a worldwide disease,caused by Streptomyces spp.,and its presence reduces the market value of potatoes.A nontoxic and potentially effective approach in many control strategies is the use of antagonistic microbes as biocontrol agents.In this study,Bacillus atrophaeus DX-9 was isolated and assessed for its ability to protect against CS.Through integrated metagenomic and metabolomic analyses,changes in the soil microbial community structure and soil properties were analyzed to understand the effects of Bacillus atrophaeus DX-9 on CS.These studies revealed that DX-9 inoculation could significantly decrease CS disease rate,disease index,and the number of CS pathogens,along with an increase in soil N and P content.Our metagenomic assays identified 102 phyla and 1154 genera,and DX-9 inoculation increased the relative abundances of the phyla Pseudomonadota,Chloroflexota and Gemmatimonadota.Additionally,an increase in the relative abundance of genera,such as Bradyrhizobium,Agrobacterium,and Nitrobacter,were significantly and positively correlated with soil N and P.Metabolomic analysis revealed that DX-9 inoculation significantly increased the soil levels of phytolaccoside A,7,8-dihydropteroic acid,novobiocin,and azafrin.These compounds were enriched in microbe pathway metabolites,including xenobiotic biodegradation and metabolism,biosynthesis of other secondary metabolites,and metabolism of cofactors and vitamins.In summary,the use of Bacillus atrophaeus DX-9 against potato CS offers an alternative biocontrol method that can improve both soil microbial community and properties.This study provides insight into the potential mechanisms by which microbial inoculants can control CS disease.展开更多
Objectives： This pilot study of employing chlorine dioxide （CD） gas to disinfect gastrointestinal endoscopes was conducted to meet the expectations of many endoscopy units in China for a high-efficiency and low-cos...Objectives： This pilot study of employing chlorine dioxide （CD） gas to disinfect gastrointestinal endoscopes was conducted to meet the expectations of many endoscopy units in China for a high-efficiency and low-cost disin- fectant. Methods： An experimental prototype with an active circulation mode was designed to use CD gas to disinfect gastrointestinal endoscopes. One type of testing device composed of polytetrafluoroethylene （PTFE） tubes （2 m long, inner diameter 1 mm） and bacterial carrier containers was used to simulate the channel of the endoscope. PTFE bacterial carriers inoculated with Bacillus atrophaeus with or without organic burden were used to evaluate the spor- icidal activity of CD gas. Factors including exposure dosage, relative humidity （RH）, and flow rate （FR） influencing the disinfection effect of CD gas were investigated. Moreover, an autoptic disinfecting test on eight real gastrointestinal endoscopes after clinical use was performed using the experimental prototype. Results： IRH, exposure dosage, or- ganic burden, and the FIR through the channel significantly （P〈0.05） affected the disinfection efficacy of CD gas for a long and narrow lumen. The log reduction increased as FR decreased. Treatment with 4 mg/L CD gas for 30 min at 0.8 L/min FR and 75% IRH, resulted in complete inactivation of spores. Furthermore, all eight endoscopes with a maximum colony-forming unit of 915 were completely disinfected. The cost was only 3 CNY （0.46 USD） for each endoscope. Conclusions： The methods and results reported in this study could provide a basis for further studies on using CD gas for the disinfection of endoscopes.展开更多
Disinfection was investigated in high-density ozone produced by dielectric barrier discharge under atmospheric pressure. Disinfection was studied on three-dimensional carriers made of hydrophilic vinyl-polysiloxane im...Disinfection was investigated in high-density ozone produced by dielectric barrier discharge under atmospheric pressure. Disinfection was studied on three-dimensional carriers made of hydrophilic vinyl-polysiloxane impression material and granular acrylic resin used for oral surgery. Experimental results indicate disinfection of spore-forming bacteria: Geobacillus stearothermophilus and Bacillus atrophaeus, and selected species of opportunistic pathogens: Aspergillus niger, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, and Candida albicans.展开更多
基金supported by the Inner Mongolia Autonomous Region Key Technology Tackling Programmed(Grant number:2021GG0300)by Hebei Science and Technology Major Project(22287501Z)by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant number:XDA28030202-3,XDA24020104).
文摘Potato common scab(CS)is a worldwide disease,caused by Streptomyces spp.,and its presence reduces the market value of potatoes.A nontoxic and potentially effective approach in many control strategies is the use of antagonistic microbes as biocontrol agents.In this study,Bacillus atrophaeus DX-9 was isolated and assessed for its ability to protect against CS.Through integrated metagenomic and metabolomic analyses,changes in the soil microbial community structure and soil properties were analyzed to understand the effects of Bacillus atrophaeus DX-9 on CS.These studies revealed that DX-9 inoculation could significantly decrease CS disease rate,disease index,and the number of CS pathogens,along with an increase in soil N and P content.Our metagenomic assays identified 102 phyla and 1154 genera,and DX-9 inoculation increased the relative abundances of the phyla Pseudomonadota,Chloroflexota and Gemmatimonadota.Additionally,an increase in the relative abundance of genera,such as Bradyrhizobium,Agrobacterium,and Nitrobacter,were significantly and positively correlated with soil N and P.Metabolomic analysis revealed that DX-9 inoculation significantly increased the soil levels of phytolaccoside A,7,8-dihydropteroic acid,novobiocin,and azafrin.These compounds were enriched in microbe pathway metabolites,including xenobiotic biodegradation and metabolism,biosynthesis of other secondary metabolites,and metabolism of cofactors and vitamins.In summary,the use of Bacillus atrophaeus DX-9 against potato CS offers an alternative biocontrol method that can improve both soil microbial community and properties.This study provides insight into the potential mechanisms by which microbial inoculants can control CS disease.
基金Project supported by the National High-Tech R&D Program(863)of China(No.2014AA021405)
文摘Objectives： This pilot study of employing chlorine dioxide （CD） gas to disinfect gastrointestinal endoscopes was conducted to meet the expectations of many endoscopy units in China for a high-efficiency and low-cost disin- fectant. Methods： An experimental prototype with an active circulation mode was designed to use CD gas to disinfect gastrointestinal endoscopes. One type of testing device composed of polytetrafluoroethylene （PTFE） tubes （2 m long, inner diameter 1 mm） and bacterial carrier containers was used to simulate the channel of the endoscope. PTFE bacterial carriers inoculated with Bacillus atrophaeus with or without organic burden were used to evaluate the spor- icidal activity of CD gas. Factors including exposure dosage, relative humidity （RH）, and flow rate （FR） influencing the disinfection effect of CD gas were investigated. Moreover, an autoptic disinfecting test on eight real gastrointestinal endoscopes after clinical use was performed using the experimental prototype. Results： IRH, exposure dosage, or- ganic burden, and the FIR through the channel significantly （P〈0.05） affected the disinfection efficacy of CD gas for a long and narrow lumen. The log reduction increased as FR decreased. Treatment with 4 mg/L CD gas for 30 min at 0.8 L/min FR and 75% IRH, resulted in complete inactivation of spores. Furthermore, all eight endoscopes with a maximum colony-forming unit of 915 were completely disinfected. The cost was only 3 CNY （0.46 USD） for each endoscope. Conclusions： The methods and results reported in this study could provide a basis for further studies on using CD gas for the disinfection of endoscopes.
文摘Disinfection was investigated in high-density ozone produced by dielectric barrier discharge under atmospheric pressure. Disinfection was studied on three-dimensional carriers made of hydrophilic vinyl-polysiloxane impression material and granular acrylic resin used for oral surgery. Experimental results indicate disinfection of spore-forming bacteria: Geobacillus stearothermophilus and Bacillus atrophaeus, and selected species of opportunistic pathogens: Aspergillus niger, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, and Candida albicans.
