Frontiers of Environmental Science & Engineering
·
2024
·Vol. 18
·期 11
·1-13
·
IF 6.1
Chen Yuchao,Dong Kun,Zhang Yiming,Zheng Junjian,Jiang Minmin,Wang Dunqiu,Zhang Xuehong,Huang Xiaowu,Zhou Lijie,Li Haixiang
The slow growth rate of autotrophic bacteria and regulation of biofilm thickness are critical factors that limit the development of a hydrogen-based membrane biofilm reactor (H 2 -MBfR). The acyl-homoserine lactone (AHL) mediated quorum sensing (QS) system is a crucial mechanism regulating biofilm behavior. However, the AHLs that promote biofilm formation in autotrophic denitrification systems and their underlying mechanisms, remain unclear. This study explored the impact of AHL-mediated QS signaling molecules on biofilm development in H 2 -MBfR. This study revealed that C 14 -HSL and C 4 -HSL are potential signaling molecules that enhanced biofilm formation in long-term stable operating H 2 -MBfR. Subsequent short-term experiments with C 14 -HSL and C 4 -HSL confirmed their ability to increase bacterial adhesion to carrier surfaces by promoting the production of extracellular polymeric substances (EPS). Functional gene annotation indicated that exogenous C 14 -HSL and C 4 -HSL increased the abundance of signal transduction (increased by 0.250%–0.375%), strengthening the inter bacterial QS response while enhancing cell motility (increased by 0.24% and 0.21%, respectively) and biological adhesion (increased by 0.044% and 0.020%, respectively), thereby accelerating the initial bacterial attachment to hollow fiber membranes and facilitating biofilm development. These findings contribute to the understanding of microbial community interactions in H 2 -MBfRs and provide novel approaches for biofilm management in wastewater treatment systems.
研究领域:
环境工程
·
微生物学
✓ 已验证
DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2023
·
IF 8.1
Danliangmin Song,Ai Jia,Xuehe Qi,Kai Dong,Shiyu Liu,Chaoxin Man,Xinyan Yang,Yujun Jiang
Bacterial biofilm is a protective matrix composed of metabolites secreted by bacteria that envelop bacteria. By forming a biofilm, bacteria can considerably improve their environmental tolerance. In food-related processing environment, different types of microorganisms are often present in biofilms. The main contaminating strain in the powdered infant formula (PIF) processing environment, Cronobacter sakazakii and Staphylococcus aureus continues to pollute the PIF processing environment after biofilm production. This study selected Cronobacter sakazakii with a weak biofilm-forming ability as one of the test organisms. The coexistence of Cronobacter sakazakii and Staphylococcus aureus on the surface of production equipment was simulated to analyze the interaction. Biofilm formation in the co-culture group was significantly higher than the others. In-depth study of the effect of Staphylococcus aureus on the biofilm formation genes of Cronobacter sakazakii . Results show two bacteria can coexist on the surface of a metal device, forming a more compact hybrid biofilm structure. Under co-culture conditions, S. aureus increased bcsA and fliD expression in Cronobacter sakazakii , whereas decreased bcsC expression. Signaling molecules produced by Staphylococcus aureus (Autoinducer 2) significantly promoted the biofilm formation of Cronobacter sakazakii at the concentration of 0–500 ng/mL (0.099–0.177) and up-regulated the expression of bcsA , filD and flhD genes.
研究领域:
微生物学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Foods
·
2021
·Vol. 10
·期 11
·2614
·
IF 4.35
Qing-Hui Wen,Rui Wang,Si-Qi Zhao,Bo-Ru Chen,Xin-An Zeng
Taking into consideration the importance of biofilms in food deterioration and the potential risks of antiseptic compounds, antimicrobial agents that naturally occurring are a more acceptable choice for preventing biofilm formation and in attempts to improve antibacterial effects and efficacy. Citrus flavonoids possess a variety of biological activities, including antimicrobial properties. Therefore, the anti-biofilm formation properties of the citrus flavonoid naringenin on theStaphylococcus aureusATCC 6538 (S. aureus) were investigated using subminimum inhibitory concentrations (sub-MICs) of 5~60 mg/L. The results were confirmed using laser and scanning electron microscopy techniques, which revealed that the thick coating ofS. aureusbiofilms became thinner and finally separated into individual colonies when exposed to naringenin. The decreased biofilm formation ofS. aureuscells may be due to a decrease in cell surface hydrophobicity and exopolysaccharide production, which is involved in the adherence or maturation of biofilms. Moreover, transcriptional results show that there was a downregulation in the expression of biofilm-related genes and alternative sigma factorsigBinduced by naringenin. This work provides insight into the anti-biofilm mechanism of naringenin inS. aureusand suggests the possibility of naringenin being used in the industrial food industry for the prevention of biofilm formation.Keywords:naringenin;biofilm formation;cell surface hydrophobicity;confocal laser scanning microscopy;biofilm-related genes
研究领域:
食品科学
·
微生物学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CONTROL
·
2018
·
IF 3.667
Jin-Rong Bai,Kai Zhong,Yan-Ping Wu,Grosu Elena,Hong Gao
The aim of this study was to evaluate the inhibitory activity of shikimic acid (SA) against biofilm formation of Staphylococcus aureus and to explore its potential molecular mechanism. Crystal violet staining assay showed that SA clearly reduced the biomass of the biofilm at its sub-MICs. Light microscopic images and scanning electron microscope (SEM) observations suggested that SA inhibited the biofilm adhesion on glass slides and induced apparent collapse of biofilm architecture. In addition, XTT reduction assay and confocal laser scanning microscopic images illustrated that the metabolic activity and the viability of the SA-treated biofilm cells significantly decreased. Cell mobility of the SA-treated S. aureus was also inhibited. These observations suggested that SA inhibited the initial biofilm formation by interfering the metabolic activity, the cell viability, and the cell mobility of S. aureus . However, SA failed to disrupt the one-day-old mature biofilm of S. aureus even at the concentrations higher than MIC, suggesting that SA disturbed the early steps in the biofilm formation of S. aureus . qRT-PCR analyses showed that SA down-regulated the transcription of sarA , while up-regulated the transcription of agrA , which resulted in the prevention of biofilm formation. So, SA could be a potential antibiofilm agent to inhibit biofilm formation of S. aureus .
研究领域:
微生物学
·
药理学
·
分子生物学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jianguo Li,Wanli Yan,Shikan Zheng,Chengsong Ye,Yangying Zhao,Xin Yu
Membrane types are known to have a decisive effect on the operational efficiency of membrane-bound reactors. The gas-permeable membrane, serving as the biofilm growth and oxygen transfer medium, plays a vital role in the membrane-aerated biofilm reactor (MABR). However, few studies have thoroughly investigated how membrane types affect MABR performance. Four parallel MABRs were equipped with different membrane types: microporous PTFE (R1), dense silicone (R2), composite A (R3), and composite B (R4) membranes. Results showed that the R3 and R4 exhibited comparable and superior COD and nitrogen removal efficiency relative to R1, maintaining stable transmembrane pressure. XDLVO theory was used to assess the interfacial interaction energy between sludge flocs and membrane surfaces. Polar forces were crucial for sludge adhesion, affecting biofilm formation and growth. Composite B exhibited the lowest energy barrier (2529 KT), leading to the fastest biofilm formation and thicker biofilms, which enhance nitrogen removal. PTFE exhibited the highest energy barrier (9655 KT), resulting in the most extended biofilm cultivation period and the thinnest biofilm. Based on fluorescent in-situ hybridization (FISH), membrane types significantly affect the distribution of nitrogen-removing microbial communities. As the biofilm thickened, the stratification of the nitrifying bacterial population became increasingly pronounced, forming distinct layers within the biofilm. Nitrosomonas and Nitrobacter dominated the biofilm near the membrane, while Nitrospira was most abundant in the outer biofilm. The outermost biofilm layer was predominantly composed of heterotrophic denitrifying bacteria (HDB). The research has shown that different biofilm types exhibit heterogeneity stratification in nitrifying bacteria and HDB. 16S rRNA genes sequencing revealed that Nitrospira was the predominant nitrifying genus within the heterotrophic/autotrophic biofilm.
研究领域:
环境工程
·
微生物学
✓ 已验证
DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2024
·
IF 7
Luyao Fan,Hongchao Dai,Wenyuan Zhou,Lei Yuan,Jia Yang,Zhenquan Yang,Xin-an Jiao
Bacillus licheniformis , a quick and strong biofilm former, is served as a persistent microbial contamination in the dairy industry. Its biofilm formation process is usually regulated by environmental factors including the divalent cation Ca 2+ . This work aims to investigate how different concentrations of Ca 2+ change biofilm-related phenotypes (bacterial motility, biofilm-forming capacity, biofilm structures, and EPS production) of dairy B . licheniformis strains. The Ca 2+ ions dependent regulation mechanism for B . licheniformis biofilm formation was further investigated by RNA-sequencing analysis. Results revealed that supplementation of Ca 2+ increased B . licheniformis biofilm formation in a dose-dependent way, and enhanced average coverage and thickness of biofilms with complex structures were observed by confocal laser scanning microscopy. Bacterial mobility of B. licheniformis was increased by the supplementation of Ca 2+ except the swarming ability at 20 mM of Ca 2+ . The addition of Ca 2+ decreased the contents of polysaccharides but promoted proteins production in EPS, and the ratio of proteins/polysaccharides content was significantly enhanced with increasing Ca 2+ concentrations. RNA-sequencing results clearly indicated the variation in regulating biofilm formation under different Ca 2+ concentrations, as 939 (671 upregulated and 268 downregulated) and 951 genes (581 upregulated and 370 downregulated) in B. licheniformis BL2-11 were induced by 10 and 20 mM of Ca 2+ , respectively. Differential genes were annotated in various KEGG pathways, including flagellar assembly, two-component system, quorum sensing, ABC transporters, and related carbohydrate and amino acid metabolism pathways. Collectively, the results unravel the significance of Ca 2+ as a biofilm-promoting signal for B. licheniformis in the dairy industry.
研究领域:
微生物学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Dan Song,Lu Wang,Weikai Sun,Yingjie Zhang,Binghan Xie,Ying Zhao,Wei Wang,Peizhi Wang,Jun Ma,Wei Cheng
Ultralow pressure filtration system, which integrates the dual functionalities of biofilm degradation and membrane filtration, has gained significant attention in water treatment due to its superior contaminant removal efficiency. However, it is a challenge to mitigate membrane biofouling while maintaining the high activity of biofilm. This study presents a novel ceramic-based ultrafiltration membrane functionalized with tourmaline nanoparticles to address this challenge. The incorporation of tourmaline nanoparticles enables the release of nutrient elements and the generation of an electric field, which enhances the biofilm activity on the membrane surface and simultaneously alleviates intrapore biofouling. The tourmaline-modified ceramic membrane (TCM) demonstrated a significant antifouling effect, with a substantial increase in water flux by 60 %. Additionally, the TCM achieved high removal efficiencies for contaminants (48.78 % in TOC, 22.28 % in UV 254 , and 24.42 % in TN) after 30 days of continuous operation. The fouling resistance by various constituents in natural water was individually analyzed using model compounds. The TCM with improved electronegativity and hydrophilicity exhibited superior resistance to irreversible fouling through increased electrostatic repulsion and reduced adhesion to foulants. Comprehensive characterizations and analyses, including interfacial interaction energies, redox reaction processes, and biofilm evolutions, demonstrated that the TCM can release nutrient elements to facilitate the development of functional microbial community within the biofilm, and generate reactive oxygen species (ROS) on the membrane surface to the degrade contaminants and mitigate membrane biofouling. The electric field generated by tourmaline nanoparticles can promote electron transfer in the Fe(III)/Fe(II) cycle, ensuring a stable and sustainable generation of ROS and bactericidal negative ions. These synergistic functions enhance contaminant removal and reduce irreversible fouling of the TCM. This study provides fundamental insights into the role of tourmaline-modified surfaces in enhancing membrane filtration performance and fouling resistance, inspiring the development of high-performance, anti-fouling membranes.
研究领域:
环境科学
·
材料科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Haiwei Ji,Haolu Hu,Qu Tang,Xiaoxia Kang,Xiaodi Liu,Lingfeng Zhao,Rongrong Jing,Mingmin Wu,Guo Li,Xiaobo Zhou,Jinxia Liu,Qi Wang,Hui Cong,Li Wu,Yuling Qin
The biofilm resistance of microorganisms has severe economic and environmental implications, especially the contamination of facilities associated with human life, including medical implants, air-conditioning systems, water supply systems, and food-processing equipment, resulting in the prevalence of infectious diseases. Once bacteria form biofilms, their antibiotic resistance can increase by 10–1,000-fold, posing a great challenge to the treatment of related diseases. In order to overcome the contamination of bacterial biofilm, destroying the biofilm’s matrix so as to solve the penetration depth dilemma of antibacterial agents is the most effective way. Here, a magnetically controlled multifunctional micromotor was developed by using H 2 O 2 as the fuel and MnO 2 as the catalyst to treat bacterial biofilm infection. In the presence of H 2 O 2 , the as-prepared motors could be self-propelled by the generated oxygen microbubbles. Thereby, the remotely controlled motors could drill into the EPS of biofilm and disrupt them completely with the help of bubbles. Finally, the generated highly toxic •OH could efficiently kill the unprotected bacteria. This strategy combined the mechanical damage, highly toxic •OH, and precise magnetic guidance in one system, which could effectively eliminate biologically infectious fouling in microchannels within 10 min, possessing a wide range of practical application prospects especially in large scale and complex infection sites.
研究领域:
生物医学工程
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
·
2024
·
IF 5
Xueying Song,Jiamu Kang,Xingyan Wei,Liu Liu,Yongfeng Liu,Feng Wang
Shigella flexneri has the ability to contaminate pork and cause foodborne diseases. This study aimed to examine the effectiveness of linalool (a natural preservative) against S. flexneri and explore its potential application in contaminated pork. The results showed that linalool was capable of damaging the cell membrane and binding to the DNA of S. flexneri , and inhibiting biofilm formation and disrupting mature biofilms. The antibacterial effectiveness of linalool on the surface of pork was further demonstrated by analyzing the physicochemical properties of the pork ( i.e. , weight loss rate, pH value, color index, and TVB-N value) and its protein profiles. Linalool did not completely kill S. flexneri in pork at minimum bactericidal concentration (MBC) concentration and its antibacterial effect of linalool was stronger during the initial stage of storage. During storage, linalool influenced the abundance of specific proteins in the pork, particularly those involved in pathways related to fat metabolism. These findings offer novel insights into the antibacterial efficacy of linalool and its underlying mechanism in pork.
研究领域:
食品科学
·
微生物学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Natural Product Communications
·
2021
·
IF 0.986
Zheng Liu,Lihua Zhang,Jincai Wang,Yanping Li,Yiqun Chang,Xiaoling Huang,Jun Duan,Yilong Ai,Xuxin Zeng,Jialiang Guo
Biofilm formation is considered as a crucial factor in various oral diseases, such as dental caries. The quorum sensing (QS) signaling system was proved to have a crucial role in the microbial dental plaque biofilm formation of Streptococcus mutans (S. mutans). LuxS was critical to regulating the QS system and survival of the bacterium, and, therefore, compounds which target LuxS may be a potential therapy for dental caries. The binding activities of 37,170 natural compounds to LuxS were virtually screened in this study. Baicalein and paeonol were chosen for further research of the binding mode and ΔG values with LuxS. Both baicalein and paeonol inhibited the biofilm formation without influence on the growth of S. mutans. Baicalein also distinctly reduced the production of both rhamnolipids and acids. The results provide us with a new approach to combat dental caries instead of the traditional use of antibacterial chemicals.
研究领域:
微生物学
·
药物化学
·
口腔医学
✓ 已验证
DOI
高影响因子
Biomaterials Science
·
2025
·
IF 5.7
Lihui Yuwen,Yuan Liu,Fengjiao Xu,Chi Zhang,Xiaolong Chen,Zhaowei Yin,Bin Liang,Lianhui Wang
Bacterial biofilms are difficult to treat with traditional antibiotics. Ultrasound (US)-responsive antibacterial agents have emerged as promising alternatives for the treatment of bacterial biofilm infections. However, they often suffer from antibiotic dependence, lack of targeting, and low antibacterial efficiency. Herein, we develop Fe3O4/MnCO3 microbubbles (FMMB) by self-assembly of Fe3O4 nanoparticles (Fe3O4 NPs) and MnCO3 nanoparticles (MnCO3 NPs). By the direction of magnetic field (MF), FMMB can be targeted to the Staphylococcus aureus (MRSA) biofilm. Under US irradiation, FMMB can destroy the structure of MRSA biofilms by cavitation-induced mechanical effects and kill bacteria by MnCO3 NPs generated reactive oxygen species (ROS) through the sonodynamic effect. In the mice model with catheter MRSA biofilm infection, FMMB removed 70.4% of the biofilm with MF and US, and the bacteria inactivation efficiency reached as high as 99.999% (4.9 Log). This work develops multifunctional microbubbles with both US-responsive mechanical and sonodynamic effects for biofilm destruction and MF-responsive properties for biofilm targeting, which provides a promising strategy for the design of antibiofilm agents to effectively treat bacterial biofilm infections.
研究领域:
医学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2018
·
IF 5.807
Longfei Wang,Yi Li,Li Wang,Mengjie Zhu,Xiaoxiao Zhu,Chen Qian,Wenwei Li
EPS can affect the migration of antibiotics in biofilm reactors, however the roles of biofilm EPS on the fate of antibiotics and the protective mechanisms to bacterial community remain unknown. We investigated the transport of three representative antibiotics in the biofilm suspension from a moving bed biofilm reactor. Spectral analysis suggested that proteins dominated the interactions between EPS and antibiotics. The adsorbed amounts of antibiotics onto EPS accounted for 14.5%, 88.2% and 13.1% of total concentration for sulfamethizole, tetracycline and norfloxacin, respectively at the biodegradation stage. The respiratory rates and representative enzymatic activities all experienced declines for biofilm without EPS in exposure to antibiotics. Gene sequencing results indicated that the bacterial community in biofilm without EPS was more vulnerable to antibiotics shocks. Our results demonstrated the protective roles of biofilm EPS in resisting antibiotics stresses, which provides important implications for understanding the bioremediation of antibiotics in biofilm systems.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）