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Polyhydroxybutyrates (PHB) are granular polyesters synthesized by many bacteria as a carbon and energy source in environments where substances such as nitrogen, oxygen, carbon, and phosphorus are limited. Polyhydroxybutyrates is biodegradable, consisting of hydrophobic long chains, and is non-toxic. It is classified as one of the basic polymers of polyhydroxyalkanoates. In this study, the Polyhydroxybutyrates production of Bacillus cereus (ATCC 10876) and Cupriavidus necator (formerly Ralstonia eutropha ATCC17699) in the presence of different minimal carbon sources was investigated under static and shaking (150 rpm) states. According to the results of the research, the highest PHB production was observed in Bacillus cereus PBS + 1% xylose medium (7.395 µg/ml) in static conditions; Cupriavidus necator exhibited the highest production of polyhydroxybutyrates under shaking conditions in PBS + 1% fructose medium (9.626 µg/ml). The lowest polyhydroxybutyrates production was observed in Cupriavidus necator in PBS + 1% maltose medium (0.027 µg/ml) under static conditions; however, under shaking conditions, it was carried out in PBS + 1% dextrose medium (0.122 µg/ml). Considering these results, it is evident that there is an increase in the production of polyhydroxybutyrates by microorganisms as the shaking speed. [ABSTRACT FROM AUTHOR]

Purpose: Chronic suppurative otitis media (CSOM) is a prominent contributor to preventable hearing loss globally. Probiotic therapy has attracted research interest in human infectious and inflammatory disease. As the most prevalent probiotic, the role of Lactobacillus in CSOM remains poorly defined. This study aimed to investigate the antipathogenic effects and underlying mechanism of Lactobacillus on CSOM. Methods: RNA sequencing of granulation of middle ear cavity from CSOM patients and lavage fluid of middle ear from normal volunteer was conducted. Human middle ear epithelial cells (HMEEC) and rats infected with Bacillus cereus (B. cereus) and Staphylococcus aureus (S. aureus) were used for CSOM constructing. Western blot, qPCR and Vybrant™ Alexa Fluor™ 488 lipid raft labeling were performed to explore the possible molecular mechanism by which lipid raft linker (RFTN1) regulates lipid raft/toll-like receptor 4 (TLR4). ELISA and HE staining was utilized to evaluate the effect of Lactobacillus on the progression of CSOM in vivo. Results: Based on RNA Sequence analysis, a total of 3646 differentially expressed genes (1620 up-regulated and 2026 down-regulated) were identified in CSOM. RFTN1 was highly expressed in CSOM. Inhibition of RFTN1 not only reduced the inflammatory response of CSOM but also suppressed the formation of lipid rafts. Further investigation revealed that RFTN1 inhibition could reduce the expression of TLR4, which also localizes to the lipid rafts. TLR4 responds to RFTN1-mediated inflammatory responses in CSOM. We treated the CSOM model with Lactobacillus, which has great potential for alleviating the inflammatory response, and found that Lactobacillus attenuated the development of CSOM by reducing RFTN1 and TLR4 expression. Conclusion: In conclusion, these findings suggest a crucial role for Lactobacillus in alleviating CSOM progression and uncovered the molecular mechanism involving Lactobacillus-regulated inhibition of the RFTN1-lipid raft-TLR4 signaling pathway under CSOM conditions. [ABSTRACT FROM AUTHOR]

Abstract Background and aim Pathogenic Escherichia coli is a known harmful microorganism that takes advantage of favorable conditions to cause various infections in healthcare settings, such as bloodstream infections related to catheters, as well as infections in the urinary and respiratory tracts. E. coli utilizes biofilm development as a means to enhance its virulence and pathogenicity. This work aims to investigate the antibiofilm activity of α-amylase enzyme against uropathogenic E. coli (UPEC) and its effect on biofilm-regulatory genes. Methodology In this study, we evaluated the antibiofilm activity of α-amylase enzyme by spectrophotometric microtiter plate analysis and confocal laser scanning microscopy. Also, the antibacterial activity of the test enzyme was evaluated by measuring the MIC and MBC levels against UPEC. The quorum-quenching activity of α-amylase enzyme was assessed using a qRT-PCR to evaluate the impact on biofilm-regulatory genes. Results Based on our results, purified α-amylase showed MIC and MBC levels ranged between 128 and 512 µg /ml against UPEC isolates using broth microdilution assay. Crystal violet assay revealed MBIC of 128 µg/ml and MBEC of 256 µg/ml for the purified α-amylase. When the biofilm was analyzed by confocal laser scanning microscope, our results showed inhibition of biofilm thickness (56%) and live/dead cell percentages (43/55%). Furthermore, analysis of the effect on the expression of biofilm-encoding genes showed downregulation of both fimH and papC genes by 57 and 25%, respectively, upon treatment of UPEC with ½ of the MIC (64 µg/ml). Conclusions The results demonstrate that our purified α-amylase from B. cereus exhibits promising antibiofilm activities against UPEC at both phenotypic as well as genotypic levels. These findings suggest that this enzyme may serve as a natural effective tool for removing bacterial biofilms, potentially offering new therapeutic avenues for treating infections caused by UPEC.

This study aimed to examine the impact of olive leaf extract (OL-E) and olive leaf extract coating chitosan (OLCh) on Bacillus cereus and its toxin genes, as well as, the sensory qualities of refrigerated beef burgers. The primary phenolic components of olive leaf extract were oleeuropein and protocatechuic acid, identified by HPLC-DAD analysis. The concentrations of OL-E and OL-Ch that were in vitro effective against B. cereus were 62.5 mg/mL and 125 mg/mL, respectively. In burgers treated with OL-E and OL-Ch, viable B. cereus dramatically decreased (p < 0.05) over time during cold storage. The count decreased to 2 log CFU/g in the OL-E group and 1.3 log CFU/g in the OL-Ch group after thirteen days of preservation. The entFM gene expression levels on day thirteen were 0.09 in the OL-Ch group and 0.2 in the OL-E group. Conversely, the cytK gene expression levels in the OL-E and OL-Ch groups were 0.09 and 0.15, respectively. Both supplements could control physicochemical characteristics (pH, volatile basic nitrogen (TVBN), and thiobarbituric acid (TBA)) to be 6.12±1.55, 16.1±2.98, and 0.869±0.28, respectively, in the OL-E group during a storage period. Moreover, they were 5.79, 14.3±2.79, and 0.816±0.31 in the OL-Ch group. They also did not appear to affect the average sensory score of burgers. Thus OL-E and OL-Ch could be used as natural food additives to prevent B. cereus contamination in the meat industry. [ABSTRACT FROM AUTHOR]

Milk rice pudding (MRP) is a commercial and popular dairy dessert, but owing to its characteristics and valuable ingredients, it may be contaminated by many pathogenic and spoilage microorganisms. So, this study aimed to improve the quality and safety of MRP by using cinnamon and clove essential oils. Concerning the evaluation of the minimum inhibitory concentration (MIC) for both oils with 0.2, 0.5, and 1% concentrations, B. cereus and B. subtilis were sensitive (+) to cinnamon and clove 0.5%, with inhibition zones of 13.3 and 14 mm for cinnamon and 11.3 and 12 mm for clove EO, respectively. While both bacteria were very sensitive (++) to cinnamon 1% (18.8 and 19.5 mm) and clove 1% (17.3 and 18.7 mm), respectively. Therefore, MRP was prepared by adding cinnamon and clove EOs at 0.6%. Treatments containing EOs showed a significant reduction of tested microorganisms compared to controls. B. cereus wasn’t detected in clove and cinnamon EO treatments at day 21 of the storage period, while B. subtilis vanished on day 14 for the cinnamon treatment and on day 21 for clove MRP. Moreover, the results revealed the enhancement of sensory characteristics of MRP supplemented with EOs without any significant alteration in their pH values. This study recommends the addition of cinnamon and clove EOs (0.6%) to MRP, as it isn’t only an excellent substitution of chemical preservatives with powerful antibacterial efficiency but also improves the overall acceptance of the product.

This study investigated the effects of low-pressure cold plasma on the inactivation of Bacillus cereus vegetative cells and spores in an inert matrix (borosilicate glass slide) and in rice grains, using oxygen as ionization gas. Greater reductions in B. cereus counts were observed in vegetative cells rather than spores. The experimental data obtained show that both the power of the plasma treatment and the matrix proved to be determining factors in the inactivation of both the spores and vegetative cells of B. cereus. To characterize the inactivation of B. cereus, experimental data were accurately fitted to the Weibull model. A significant decrease in parameter "a", representing resistance to treatment, was confirmed with treatment intensification. Furthermore, significant differences in the "a" value were observed between spores in inert and food matrices, suggesting the additional protective role of the food matrix for B. cereus spores. These results demonstrate the importance of considering matrix effects in plasma treatment to ensure the effective inactivation of pathogenic microorganisms, particularly in foods with low water activity, such as rice. This approach contributes to mitigating the impact of foodborne illnesses caused by pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

Milk rice pudding (MRP) is a commercial and popular dairy dessert, but owing to its characteristics and valuable ingredients, it may be contaminated by many pathogenic and spoilage microorganisms. So, this study aimed to improve the quality and safety of MRP by using cinnamon and clove essential oils. Concerning the evaluation of the minimum inhibitory concentration (MIC) for both oils with 0.2, 0.5, and 1% concentrations, B. cereus and B. subtilis were sensitive (+) to cinnamon and clove 0.5%, with inhibition zones of 13.3 and 14 mm for cinnamon and 11.3 and 12 mm for clove EO, respectively. While both bacteria were very sensitive (++) to cinnamon 1% (18.8 and 19.5 mm) and clove 1% (17.3 and 18.7 mm), respectively. Therefore, MRP was prepared by adding cinnamon and clove EOs at 0.6%. Treatments containing EOs showed a significant reduction of tested microorganisms compared to controls. B. cereus wasn't detected in clove and cinnamon EO treatments at day 21 of the storage period, while B. subtilis vanished on day 14 for the cinnamon treatment and on day 21 for clove MRP. Moreover, the results revealed the enhancement of sensory characteristics of MRP supplemented with EOs without any significant alteration in their pH values. This study recommends the addition of cinnamon and clove EOs (0.6%) to MRP, as it isn't only an excellent substitution of chemical preservatives with powerful antibacterial efficiency but also improves the overall acceptance of the product. [ABSTRACT FROM AUTHOR]

Hydrocarbon constituents of petroleum are persistent, bioaccumulated, and bio-magnified in living tissues, transported to longer distances, and exert hazardous effects on human health and the ecosystem. Bioaugmentation with microorganisms like bacteria is an emerging approach that can mitigate the toxins from environmental sources. The present study was initiated to target the petroleum-contaminated soil of gasoline stations situated in Lahore. Petroleum degrading bacteria were isolated by serial dilution method followed by growth analysis, biochemical and molecular characterization, removal efficiency estimation, metabolites extraction, and GC-MS of the metabolites. Molecular analysis identified the bacterium as Bacillus cereus, which exhibited maximum growth at 72 hours and removed 75% petroleum. Biochemical characterization via the Remel RapID™ ONE panel system showed positive results for arginine dehydrolase (ADH), ornithine decarboxylase (ODC), lysine decarboxylase (LDC), o-nitrophenyl-β-D-galactosidase (ONPG), p-nitrophenyl-β-D-glucosidase (βGLU), p-nitrophenyl-N-acetyl-β-D-glucosaminidase (NAG), malonate (MAL), adonitol fermentation (ADON), and tryptophane utilization (IND). GC-MS-based metabolic profiling identified alcohols (methyl alcohol, o-, p- and m-cresols, catechol, and 3-methyl catechol), aldehydes (methanone, acetaldehyde, and m-tolualdehyde), carboxylic acid (methanoic acid, cis,cis-muconic acid, cyclohexane carboxylic acid and benzoic acid), conjugate bases of carboxylic acids (benzoate, cis,cis-muconate, 4-hydroxybenzoate, and pyruvate) and cycloalkane (cyclohexene). It suggested the presence of methane, methylcyclohexane, toluene, xylene, and benzene degradation pathways in B. cereus.

Background: Bacillus cereus (B. cereus) biofilm is grown not only on medical devices but also on different substrata and is considered a potential hazard in the food industry. Quorum sensing (QS) plays a serious role in the synthesis of biofilm with its surrounding extracellular matrix enabling irreversible connection of the bacteria. Aim: The present study directed to determine the prevalence, antimicrobial resistance patterns, and biofilm formation ability of B. cereus in meat and meat products in Egypt. Methods: A total of one hundred and fifty meat and meat product samples were included in this study. The samples were transferred to the Bacteriology Laboratory for further bacteriological examination. Thereafter, the antimicrobial, antiquorum sensing and antibiofilm potential of apple cider vinegar (ACV) on B. cereus were evaluated. Results: Thirty four samples out of 150 samples (22.67%) were positive for B. cereus. Antimicrobial susceptibility testing revealed that all B. cereus isolates were resistant to ampicillin and colistin however none of them were resistant to ciprofloxacin and imipenem. All multidrug resistant (MDR) B. cereus isolates (n = 12) could produce biofilms with varying degrees; among them, 6 (50%), 3 (25%) and 3 (25%) isolates were weak, moderate and strong biofilm producers, respectively. Interestingly, the ACV exhibited marked inhibitory activities against B. cereus isolates with minimum inhibitory concentrations (MIC) ranging from 2 to 8 μg/mL. Moreover, it showed a good antibiofilm activity (> 50% reduction of biofilm formation) after exposure of biofilm producing B. cereus isolates to the minimum biofilm inhibitory concentrations 50 (MBIC50) of 4 μg/mL. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) revealed down-regulation of biofilm genes (tasA and sipW) and their regulator (plcR) in strong biofilm producers in comparison to those of the control. Conclusion: Our study is the first report, which spotlight on the ACV activity against B. cereus biofilm and its consequence as a strong antibacterial and antibiofilm agent in food industry and human health risk. [Open Vet J 2024; 14(1.000): 186-199]

The physiology (membrane integrity, intracellular esterase and redox activity) of individual pathogenic bacteria is various in different growing phase, which has a profound significance for food safety testing and control. In this work, the aptamers against B. cereus in different growing phase was firstly selected based on whole bacterium-SELEX screening approach. Out of 32 candidate aptamers screened, aptamer B15 and B16 showed relatively high binding affinity with an apparent dissociation constant (Kd value) of 16.13 ± 4.98 nM and 20.67 ± 5.23 nM, respectively. A label-free impedance based aptasensor was further fabricated based on the screened aptamer, immobilized onto the GCE/Au surface. With the addition of B. cereus, the electron transfer process was prevented and exhibited a significant decrease in the electron-transfer resistance. Under optimal conditions, the fabricated aptasensor can achieve high sensitive detection of B. cereus as low as 10 cfu/mL. A satisfactory recovery of 90.5%–105.3% was achieved for the B. cereus detection in spiked milk samples, exhibiting its prospect in the sensitive detection of B. cereus in daily life.

World health organization (WHO) recognizes antimicrobial resistance as a silent pandemic. It is estimated that 10 million deaths will occur annually due to antimicrobial resistant infections by 2050. Phytochemicals exhibit activity against drug resistant bacteria, offering potential for developing novel antibacterial agents. Garlic organosulphur compounds exhibit potent activity against a variety of drug-resistant bacteria. Identifying their mechanism of action is critical to assess their potential to be developed as novel antibacterial agents. Diallyl sulfide (DAS) is a component of garlic essential oil with antibacterial activity. In this study antibacterial activity of DAS was investigated against Bacillus cereus, a common foodborne pathogen. DAS exhibited activity against B. cereus with a minimum inhibitory concentration (MIC) of 54.75 mM. The presence of DAS significantly reduced the growth of B. cereus. The study also investigated the mechanism of antibacterial activity of DAS against B. cereus. Treating B. cereus with sub-MIC and MIC concentration of DAS resulted in a dose and time-dependent leakage of intracellular proteins. The protein leakage was enhanced at acidic pH. Scanning electron microscopy (SEM) of B. cereus treated with DAS showed deformation in the cell membrane. Thus, the data indicate that DAS exerts its antibacterial activity by compromising the membrane integrity of B. cereus. The study demonstrates DAS could be used to control B. cereus infections. The findings indicate that DAS has a membrane altering activity, suggesting that development of resistance to this mechanism is less likely and the compound could be novel antibacterial or a good adjuvant for antibiotics.

Background: Bacillus cereus (B. cereus) biofilm is grown not only on medical devices but also on different substrata and is considered a potential hazard in the food industry. Quorum sensing plays a serious role in the synthesis of biofilm with its surrounding extracellular matrix enabling irreversible connection of the bacteria. Aim: The goal of the current investigation was to ascertain the prevalence, patterns of antimicrobial resistance, and capacity for B. cereus biofilm formation in meat and meat products in Egypt. Methods: In all, 150 meat and meat product samples were used in this study. For additional bacteriological analysis, the samples were moved to the Bacteriology Laboratory. Thereafter, the antimicrobial, antiquorum sensing, and antibiofilm potential of apple cider vinegar (ACV) on B. cereus were evaluated. Results: Out of 150 samples, 34 (22.67%) tested positive for B. cereus. According to tests for antimicrobial susceptibility, every B. cereus isolates tested positive for colistin and ampicillin but negative for ciprofloxacin and imipenem. The ability to form biofilms was present in all 12 multidrug-resistant B. cereus isolates (n = 12); of these, 6 (50%), 3 (25%), and 3 (25%) isolates were weak, moderate, and strong biofilm producers, respectively. It is noteworthy that the ACV demonstrated significant inhibitory effects on B. cereus isolates, with minimum inhibitory concentrations varying between 2 and 8 μg/ml. Furthermore, after exposing biofilm-producing B. cereus isolates to the minimum biofilm inhibitory concentrations 50 of 4 μg/ml, it demonstrated good antibiofilm activity (>50% reduction of biofilm formation). Strong biofilm producers had down-regulated biofilm genes (tasA and sipW) and their regulator (plcR) compared to the control group, according to reverse transcriptase quantitative polymerase chain reaction analysis. Conclusion: Our study is the first report, that spotlights the ACV activity against B. cereus biofilm and its consequence as a strong antibacterial and antibiofilm agent in the food industry and human health risk. [ABSTRACT FROM AUTHOR]

In Ayurvedic and Unani medicine, Justicia adhatoda is a well-known medicinal herb. It is commonly known that higher plants contain antibacterial agents. The antimicrobial potential of Justicia adhatoda, alone makes a major contribution. An indicator of an antimicrobial agent's relative potential is the formation of a growth inhibition zone, which is a clear area surrounding the original agent and indicates the efficacy of the agent. The present study aimed to evaluate antimicrobial activity of at different concentrations (25, 50, 75 & 100 pg/ml) of methanol, pet ether and water extract of leaf, stem, root and flower part of J. adhatoda against Gram-negative (E. coli and P. syringe) and gram-positive (B. cereus and S. aureus) bacterial strains. Antibiotic was used as standard. Based on the data presented here in; for root, the largest zone of inhibition was found to be against B. cereus (13mm) in water extracts at 100 pg/ml concentration followed by against all other three bacteria with 12mm inhibition zone in methanol extract. For stem, the largest zone of inhibition was found to be against E. coli (17mm) in methanol extracts followed by against S. aureus with 16mm inhibition zone in methanol and water extracts (100 pg/ml concentration). In case of flower, the maximum inhibition Zone (IZ) was 17 mm against E. coli (in water extract) and S. aureus (in methanol extract) followed by P. syringe (methanol extract) with 15mm inhibition zone. For leaves, highest IZ was 17 mm against E. coli (in water extract) followed by S. aureus (in methanol and pet ether extract) with IZ of 15mm. So, this study provided referential information about the antimicrobial activity of different extracts of different parts of Justicia adhatoda L. It may be effective in identifying a new bioactive compound for the development of novel medications. [ABSTRACT FROM AUTHOR]

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Microorganisms are integral components of ecosystems, exerting profound impacts on various facets of human life. The recent United Nations General Assembly (UNGA) Science Summit emphasized the critical importance of comprehending the microbial world to address global challenges, aligning with the United Nations Sustainable Development Goals (SDGs). In agriculture, microbes are pivotal contributors to food production, sustainable energy, and environmental bioremediation. However, decades of agricultural intensification have boosted crop yields at the expense of soil health and microbial diversity, jeopardizing global food security. To address this issue, a study in West Bengal, India, explored the potential of a novel multi-strain consortium of plant growth promoting (PGP) Bacillus spp. for soil bioaugmentation. These strains were sourced from the soil’s native microbial flora, offering a sustainable approach. In this work, a composite inoculum of Bacillus zhangzhouensis MMAM, Bacillus cereus MMAM3), and Bacillus subtilis MMAM2 were introduced into an over-exploited agricultural soil and implications on the improvement of vegetative growth and yield related traits of Gylcine max (L) Meril. plants were evaluated, growing them as model plant, in pot trial condition. The study’s findings demonstrated significant improvements in plant growth and soil microbial diversity when using the bacterial consortium in conjunction with vermicompost. Metagenomic analyses revealed increased abundance of many functional genera and metabolic pathways in consortium-inoculated soil, indicating enhanced soil biological health. This innovative bioaugmentation strategy to upgrade the over-used agricultural soil through introduction of residual PGP bacterial members as consortia, presents a promising path forward for sustainable agriculture. The rejuvenated patches of over-used land can be used by the small and marginal farmers for cultivation of resilient crops like soybean. Recognizing the significance of multi-strain PGP bacterial consortia as potential bioinoculants, such technology can bolster food security, enhance agricultural productivity, and mitigate the adverse effects of past agricultural activities. [ABSTRACT FROM AUTHOR]

The soil-dwelling delta-proteobacterium Myxococcus xanthus is a model organism to study predation and competition. M. xanthus preys on a broad range of bacteria mediated by lytic enzymes, exopolysaccharides, Type-IV pilus-based motility, and specialized metabolites. Competition between M. xanthus and prey bacterial strains with various specialized metabolite profiles indicates a range of fitness, suggesting that specialized metabolites contribute to prey survival. To expand our understanding of how specialized metabolites affect predator–prey dynamics, we assessed interspecies interactions between M. xanthus and two strains of Bacillus cereus. While strain ATCC 14579 resisted predation, strain T was found to be highly sensitive to M. xanthus predation. The interaction between B. cereus ATCC 14579 and M. xanthus appears to be competitive, resulting in population loss for both predator and prey. Genome analysis revealed that ATCC 14579 belongs to a clade that possesses the biosynthetic gene cluster for production of thiocillins, whereas B. cereus strain T lacks those genes. Further, purified thiocillin protects B. cereus strains unable to produce this specialized metabolite, strengthening the finding that thiocillin protects against predation and contributes to the ecological fitness of B. cereus ATCC 14579. Lastly, strains that produce thiocillin appear to confer some level of protection to their own antibiotic by encoding an additional copy of the L11 ribosomal protein, a known target for thiopeptides. This work highlights the importance of specialized metabolites affecting predator–prey dynamics in soil microenvironments. [ABSTRACT FROM AUTHOR]

This study investigated the effects of low-pressure cold plasma on the inactivation of Bacillus cereus vegetative cells and spores in an inert matrix (borosilicate glass slide) and in rice grains, using oxygen as ionization gas. Greater reductions in B. cereus counts were observed in vegetative cells rather than spores. The experimental data obtained show that both the power of the plasma treatment and the matrix proved to be determining factors in the inactivation of both the spores and vegetative cells of B. cereus. To characterize the inactivation of B. cereus, experimental data were accurately fitted to the Weibull model. A significant decrease in parameter “a”, representing resistance to treatment, was confirmed with treatment intensification. Furthermore, significant differences in the “a” value were observed between spores in inert and food matrices, suggesting the additional protective role of the food matrix for B. cereus spores. These results demonstrate the importance of considering matrix effects in plasma treatment to ensure the effective inactivation of pathogenic microorganisms, particularly in foods with low water activity, such as rice. This approach contributes to mitigating the impact of foodborne illnesses caused by pathogenic microorganisms.

Microorganisms are integral components of ecosystems, exerting profound impacts on various facets of human life. The recent United Nations General Assembly (UNGA) Science Summit emphasized the critical importance of comprehending the microbial world to address global challenges, aligning with the United Nations Sustainable Development Goals (SDGs). In agriculture, microbes are pivotal contributors to food production, sustainable energy, and environmental bioremediation. However, decades of agricultural intensification have boosted crop yields at the expense of soil health and microbial diversity, jeopardizing global food security. To address this issue, a study in West Bengal, India, explored the potential of a novel multi-strain consortium of plant growth promoting (PGP) Bacillus spp. for soil bioaugmentation. These strains were sourced from the soil’s native microbial flora, offering a sustainable approach. In this work, a composite inoculum of Bacillus zhangzhouensis MMAM, Bacillus cereus MMAM3), and Bacillus subtilis MMAM2 were introduced into an over-exploited agricultural soil and implications on the improvement of vegetative growth and yield related traits of Gylcine max (L) Meril. plants were evaluated, growing them as model plant, in pot trial condition. The study’s findings demonstrated significant improvements in plant growth and soil microbial diversity when using the bacterial consortium in conjunction with vermicompost. Metagenomic analyses revealed increased abundance of many functional genera and metabolic pathways in consortium-inoculated soil, indicating enhanced soil biological health. This innovative bioaugmentation strategy to upgrade the over-used agricultural soil through introduction of residual PGP bacterial members as consortia, presents a promising path forward for sustainable agriculture. The rejuvenated patches of over-used land can be used by the small and marginal farmers for cultivation of resilient crops like soybean. Recognizing the significance of multi-strain PGP bacterial consortia as potential bioinoculants, such technology can bolster food security, enhance agricultural productivity, and mitigate the adverse effects of past agricultural activities.

Bacillus cereus is a Gram positive, facultative anaerobic bacterium characterized by large rod- shaped cells and an ability to form heat-resistant endospores. Because this bacterium is so widely distributed throughout nature and is frequently found in soil, it is naturally present in a wide variety of food products of both animal and plant origin. The presence of B. cereus and its virulence factors in dairy products may result in food poisoning and other illnesses. B. cereus causes two types of intestinal illness: emetic (vomiting) and diarrheal. Furthermore, the bacterium causes a variety of systemic and local infections in both immunosuppressed and immunocompetent persons. Different toxins and pathogenic factors like nonhemolytic enterotoxin Nhe, hemolytic enterotoxin Hbl, enterotoxin FM and cytotoxin K are accountable for diarrheal syndrome, meanwhile the depsipeptide cereulide toxin causes emetic syndrome. Because of its genetic similarity to Bacillus anthracis and Bacillus thuringiensis, the ability to detect this pathogen in food is frequently difficult. We reviewed characters, virulent attributes, toxins profiles of this bacterium. Current control methods are limited so future control strategies must be developed. [ABSTRACT FROM AUTHOR]

Bacillus cereus is a foodborne pathogen that has a widespread presence in the environment and frequently found in foods especially in dairy products. Raw milk contaminated with B. cereus could be the cause of its widespreadness in the environment. In this study, it was aimed to determine the genotypes, biofilm formation, antimicrobial susceptibilities, and antibiotypes of B. cereus isolates from raw milk. For this aim, B. cereus isolated and identified from 10 of 250 raw milk samples were investigated. Biofilm forming abilities were determined in vitro by Congo Red Agar Method. Kirby Bauer Disc Diffusion Method was used for determining the antibiotic susceptibilities of the isolates. According to the antibiotic susceptibility results, quantitative antibiotyping was implemented. Genotyping of the isolates were performed by RAPD-PCR. Biofilm formation was determined in 40% of the isolates. The resistances against amoxicillin-clavulanic acid, gentamicin, erythromycin, vancomycin, chloramphenicol, tetracycline, trimethoprim-sulfamethoxazole were determined in 100%, 0%, 30%, 0%, 0%, 0%, and 50% of the isolates, respectively. In the quantitative antibiotyping, the isolates showed similarity between 0.75 to 1.00. The phylogenetic similarities were calculated between 29% to 82%. In conclusion, raw milks might threat the public health because of having potential of containing the antibiotic resistant B. cereus.

The soil-dwelling delta-proteobacterium Myxococcus xanthus is a model organism to study predation and competition. M. xanthus preys on a broad range of bacteria mediated by lytic enzymes, exopolysaccharides, Type-IV pilus-based motility, and specialized metabolites. Competition between M. xanthus and prey bacterial strains with various specialized metabolite profiles indicates a range of fitness, suggesting that specialized metabolites contribute to prey survival. To expand our understanding of how specialized metabolites affect predator–prey dynamics, we assessed interspecies interactions between M. xanthus and two strains of Bacillus cereus. While strain ATCC 14579 resisted predation, strain T was found to be highly sensitive to M. xanthus predation. The interaction between B. cereus ATCC 14579 and M. xanthus appears to be competitive, resulting in population loss for both predator and prey. Genome analysis revealed that ATCC 14579 belongs to a clade that possesses the biosynthetic gene cluster for production of thiocillins, whereas B. cereus strain T lacks those genes. Further, purified thiocillin protects B. cereus strains unable to produce this specialized metabolite, strengthening the finding that thiocillin protects against predation and contributes to the ecological fitness of B. cereus ATCC 14579. Lastly, strains that produce thiocillin appear to confer some level of protection to their own antibiotic by encoding an additional copy of the L11 ribosomal protein, a known target for thiopeptides. This work highlights the importance of specialized metabolites affecting predator–prey dynamics in soil microenvironments.

Introduction: Astragalus membranaceus Fisch. ex Bunge is a traditional botanical drug with antibacterial, antioxidant, antiviral, and other biological activities. In the process of industrialization of A. membranaceus, most of the aboveground stems and leaves are discarded without resource utilization except for a small amount of low-value applications such as composting. This study explored the antibacterial activity of A. membranaceus stem and leaf extracts to evaluate its potential as a feed antibiotic substitute. Materials and methods: The antibacterial activity of the flavonoid, saponin, and polysaccharide fractions in A. membranaceus stems and leaves was evaluated by the disk diffusion method. The inhibitory activity of the flavonoid fraction from A. membranaceus stems and leaves on B. cereus was explored from the aspects of the growth curve, cell wall, cell membrane, biofilm, bacterial protein, and virulence factors. On this basis, the flavonoid fraction in A. membranaceus stems and leaves were isolated and purified by column chromatography to determine the main antibacterial components. Results: The flavonoid fraction in A. membranaceus stems and leaves had significant inhibitory activity against B. cereus, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were 1.5625 and 6.25 mg/mL, respectively. A. membranaceus stem and leaf flavonoid fraction can induce death of B. cereus in many ways, such as inhibiting growth, destroying cell wall and cell membrane integrity, inhibiting biofilm formation, inhibiting bacterial protein synthesis, and downregulating virulence factor expression. In addition, it was clear that the main flavonoid with antibacterial activity in A. membranaceus stems and leaves was isoliquiritigenin. Molecular docking showed that isoliquiritigenin could form a hydrogen bonding force with FtsZ. Conclusion: A. membranaceus stem and leaf flavonoid fractions had significant inhibitory activity against B. cereus, and the main chemical composition was isoliquiritigenin. [ABSTRACT FROM AUTHOR]

Background and Aim: Bacillus cereus is accountable for several outbreaks of diseases spread by food. Therefore, the study aimed to use routine culture methods and direct PCR to detect the foodborne bacterial pathogen and its enterotoxins. Materials and Methods: In the present study, a total of 75 Kibda sandwiches, Sausage sandwiches, Chicken Luncheons, Beef Meat luncheons, and Chicken shawarma (Fifteen samples of each) were collected from different places in Kafr El-Sheikh governorate, Egypt, from July to September 2022. isolation, identification, and rapid analysis by PCR were done to find Foodborne bacterial pathogens in samples. Results: Bacterial isolation revealed 17 positive samples from different food types. From 17 infected samples, 40% were Kibda, 26.6% were Sausage, 20% were Chicken luncheon, and 13.3% were positive for Meat luncheon and Chicken shawarma sandwiches. Using PCR to identify B. cereus from positive isolates (group A), 8 isolates were detected having groEL, nhe & cytK genes amplified at 533, 766, and 421 bp, respectively. Also, the PCR, which was used to detection of Bacillus cereus directly in positive samples (group B) and revealed that 8 B. cereus in samples with its enterotoxins genes nhe & cytK, while group C which representssome random food samples of negative isolation resultsrevealed that 3 samples were infected by B. cereus. Conclusion: PCR assay was a sensitive & specific diagnostic tool in detecting Bacillus cereus with its enterotoxins genes directly from food samples, even in the presence of low numbers of B. cereus bacteria that traditional isolation and identification methods cannot detect. [ABSTRACT FROM AUTHOR]

The Present study was undertaken to assess the prevalence of B. cereus in milk and some milk Products and its survival in yoghurt and Damietta cheese. A total of 100 samples of raw milk, Pasteurized milk, Damietta cheese and yoghurt (25 for each) were collected from supermarkets in Assiut city and were examined for isolation of B. cereus. It was isolated from 24, 32, 68 and 20% of the tested samples, respectively. All the isolated strains were confirmed positive for B. cereus except one strain for each raw milk and Damietta cheese. 14.7%, 85.3, 50.0 and 76.5% of the confirmed strains were carried Ces, Nhe, Hbl and cytK genes. Concerning its survival in yoghurt, there was a significant difference between the effect of yoghurt and acidophilus yoghurt on B. cereus growth, where the organism remained viable to the 9th day in yoghurt and failed to be isolated at the 5th day in yoghurt with probiotics. In case of Damietta cheese, 2 and 5% salt were more favorable for the pathogen growth, while 10% salt was inconvenient for its growth. In addition, the inhibitory effect of thyme essential oil was more obvious than the effect of rosemary EO, where the bacterial population was decreased to a count of 2.04 and 2.46 log cfu/ g. at the 2nd week in case of addition of 1.65% thyme EO and could not be detected at the 4th week, whereas the organism could survive to the 6th week in case of rosemary. In conclusion, strict hygienic measures must be implemented during the manufacture of dairy products and addition of biopreservatives to control B. cereus growth is substantial. [ABSTRACT FROM AUTHOR]

Copyright of Kafkas Universitesi Veteriner Fakultesi Dergisi is the property of University of Kafkas, Faculty of Veterinary Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bacillus cereus (B. cereus) is a Gram-positive, spore-forming, and facultative anaerobic bacterium that is widely distributed in the environment. Commonly, B. cereus is a soil occupant and is generally isolated from food and food products. It is a human pathogen that causes two variant types of gastrointestinal diseases: diarrheal and emetic. Diseases caused by multidrug-resistant (MDR) bacteria are difficult to be treated. In addition, group of B. cereus has several virulence factors, which play their roles in pathogenesis, infectivity and its capability to form biofilms. B. cereus biofilm is grown on medical devices either abiotic or biotic surfaces. This biofilm avoids the bacteria from the effect of antibiotics and host immune system leading to chronic infections, persistence and mortalities. Thus, it is necessary to explore new antiquorum and antibiofilm agents better than the conventional therapy to eliminate the biofilm that reflect on controlling B. cereus infections. The present review will discuss B. cereus virulence attributes, antibiotic resistance profiles, and their ability to produce biofilm as well as its molecular regulation. The application of the antiquorum and antibiofilm approaches for infection control will be illustrated as well. Finally, we will spot the light on their consequence in food industry loses and human health risk. [ABSTRACT FROM AUTHOR]

The Bacillus cereus group includes species that act as food-borne pathogens causing diarrheal and emetic symptoms. They are widely distributed and can be found in various foods. In this study, out of 550 samples of milk and cheeses, 139 (25.3%) were found to be contaminated by B. cereus sensu lato (s.l.). One isolate per positive sample was characterized by Multilocus Sequence Typing (MLST) and for the presence of ten virulence genes. Based on MLST, all isolates were classified into 73 different sequence types (STs), of which 12 isolates were assigned to new STs. Virulence genes detection revealed that 90% and 61% of the isolates harboured the nheABC and the hblCDA gene cluster, respectively. Ninety-four percent of the isolates harboured the enterotoxin genes entS and entFM; 8% of the isolates possessed the ces gene. Thirty-eight different genetic profiles were identified, suggesting a high genetic diversity. Our study clearly shows the widespread diffusion of potentially toxigenic isolates of B. cereus s.l. in milk and cheeses in the Apulia region highlighting the need to adopt GMP and HACCP procedures along every step of the milk and cheese production chain in order to reduce the public health risk linked to the consumption of foods contaminated by B. cereus s.l. [ABSTRACT FROM AUTHOR]

Conventional methods for the detection and differentiation of Bacillus cereus group species have drawbacks mostly due to the complexity of genetic discrimination between the Bacillus cereus species. Here, we describe a simple and straightforward assay based on the detected unamplified bacterial 16S rRNA by DNA nanomachine (DNM). The assay uses a universal fluorescent reporter and four all-DNA binding fragments, three of which are responsible for "opening up" the folded rRNA while the fourth stand is responsible for detecting single nucleotide variation (SNV) with high selectivity. Binding of the DNM to 16S rRNA results in the formation of the 10–23 deoxyribozyme catalytic core that cleaves the fluorescent reporter and produces a signal, which is amplified over time due to catalytic turnover. This developed biplex assay enables the detection of B. thuringiensis 16S rRNA at fluorescein and B. mycoides at Cy5 channels with a limit of detection of 30 × 103 and 35 × 103 CFU/mL, respectively, after 1.5 h with a hands-on time of ~10 min. The new assay may simplify the analysis of biological RNA samples and might be useful for environmental monitoring as a simple and inexpensive alternative to amplification-based nucleic acid analysis. The DNM proposed here may become an advantageous tool for detecting SNV in clinically significant DNA or RNA samples and can easily differentiate SNV under broadly variable experimental conditions and without prior amplification. [ABSTRACT FROM AUTHOR]

Carvacrol has great antibacterial activity against Bacillus cereus , and its action mechanism was comprehensively studied in this work. It could not only control the growth of B. cereus by affecting the integrality of cellular structure and physiological metabolism, but also inhibit the swarming motility, biofilm formation, and toxins production. To increase the stability of carvacrol during the application, the sodium casein (SC)/hydroxypropyl- β -cyclodextrin (HPCD)/carvacrol nanoemulsion was fabricated. The mean particle size and polydispersity index of the nanoemulsions were 113.8 nm and 0.23, respectively, at SC and HPCD concentrations of 2% and 1%. FTIR analysis demonstrated that carvacrol was successfully encapsulated into the nanoemulsions. The MIC and MBC of nanoemulsions against B. cereus were 0.15 and 0.30 mg/mL, respectively, which were lower than those of free carvacrol (0.19 and 0.38 mg/mL). Carvacrol in nanoemulsions showed a slow and sustained release behavior. Furthermore, the nanoemulsions had good stability (particle size <200 nm) after storage at 4 °C and 25 °C for 15 days. Notably, the nanoemulsions were effective in controlling the growth of B. cereus in whole, low-fat, and skim milk and had better antimicrobial activity than free carvacrol. The results indicated that carvacrol nanoemulsions have potential in the antibacterial application of the food industry. [Display omitted] • Carvacrol inhibited swarming motility, biofilm, and toxin production in B. cereus. • Carvacrol was successfully encapsulated in SC/HPCD nanoemulsion. • Nanoemulsions increased carvacrol stability with sustained release. • Nanoemulsions showed better antibacterial activity in milk than free carvacrol. [ABSTRACT FROM AUTHOR]

In the study, a previously isolated plant beneficial endophytic B. cereus CaB1 was selected for the detailed analysis by whole-genome sequencing. The WGS has generated a total of 1.9 GB high-quality data which was assembled into a 5,257,162 bp genome with G + C content of 35.2%. Interestingly, CaB1 genome was identified to have 40 genes with plant beneficial functions by bioinformatic analysis. At the same time, it also showed the presence of various virulence factors except the diarrhoeal toxin, cereulide. Upon comparative analysis of CaB1 with other B. cereus strains, it was found to have random distributions of virulence and plant growth promoting traits. The core genome phylogenetic analysis of the Bacillus cereus strains further showed the close relation of plant associated strains with isolates from spoiled food products. The observed genome flexibility of B. cereus thus indicates its ability to make use of diverse hosts, which can result either in beneficial or harmful effects. [ABSTRACT FROM AUTHOR]

Date palm fruit is consumed as a highly nutritious food item particularly in the Middle East. This work was designed to investigate the occurrence of filamentous moulds, their toxins in date palm fruit samples, and explore the biocontrol potential of Bacillus cereus 342-2 against few date palms associated fungal species. In total, 36 date palm fruit samples from different sources and varieties were collected from the markets in Qatar. Aspergillus and Penicillium spp. were found to contaminate most of the samples, except Akhlas samples, which were free of any fungal contamination. In total, ochratoxin A (OTA) was found in 6 (16.67%) date samples, all within the permissible limit, except one (2.7%), where the level was above the maximum permissible concentrations of 2 µg/kg. The volatile organic compounds (VOCs) of B. cereus were very effective against the growth of A. niger and A. carbonarius with an inhibition rate of 100%. Whereas their effects against A. flavus was weak as mycelia grew; however, no sporulation occurred until day 7 of co-incubation. Gas chromatography mass spectrophotometry analysis of B. cereus volatiles showed aldehyde as a major component with a peak area of 10.6%, and Undecane with a peak area of 2.02%. The inhibitory effect of VOCs was either from aldehyde alone, or a synergetic effect of the two molecules. [ABSTRACT FROM AUTHOR]

Plainly treated foods are highly recommended in the recent world, so edible packaging using encapsulated essential oils in biopolymers have afforded a premium and nontoxic food preservation technique. In this work, chitosan-based emulsions made of liposomes loaded with thyme essential oil were explored to lengthen the shelf-life of white soft cheese. Chitosan-based emulsions with TEO/liposomes, prepared by 2% wt/v chitosan solutions (CL-TEO), are active for 60 days. Antimicrobial activities were assessed via determination of total viable counts of Bacillus cereus (B. cereus) and Enterococcus faecium (E. faecium) over 4 weeks at refrigerated storage at 5ºC. Cheese samples coated with CL-TEO 2% v/v and samples coated with CL-TEO 1% v/v plus nisin kept its satisfactory appearance, as well acceptable bacterial counts for 1 month at 5ºC. The results suggested that the formulated liposomal chitosan emulsions encapsulated TEO 2% v/v and liposomal chitosan emulsion encapsulated TEO 1% v/v plus nisin might be promising natural formulas to extend the shelf life in addition to preserving the flavour of white soft cheese. [ABSTRACT FROM AUTHOR]

Astronauts remote from Earth, not least those who will inhabit the Moon or Mars, are vulnerable to disease due to their reduced immunity, isolation from clinical support, and the disconnect from any buffering capacity provided by the Earth. Here, we explore potential risks for astronaut health, focusing on key aspects of the biology of Bacillus anthracis and other anthrax-like bacilli. We examine aspects of Bacillus cereus group genetics in relation to their evolutionary biology and pathogenicity; a new clade of the Bacillus cereus group, close related to B. anthracis, has colonized the International Space Station (ISS), is still present, and could in theory at least acquire pathogenic plasmids from the other B. cereus group strains. The main finding is that the genomic sequence alignments of the B. cereus group ISS strains revealed a high sequence identity, indicating they originated from the same strain and that a close look to the genetic variations among the strains suggesting they lived, or they are living, in a vegetative form in the ISS enough time to accumulate genetic variations unique for each single strains. [ABSTRACT FROM AUTHOR]

Engineered nanoparticles are precisely synthesized to exploit unique properties conferred by their small size and high surface area for environmental, biomedical, and agricultural applications. While these physical properties dictate functionality, they can also have various intended and unintended implications for biological systems. Both the particle size and shape influence cellular uptake. Because of zinc's antibacterial properties and role as a plant micronutrient, polyvinylpyrrolidone stabilized zinc nanoparticles (ZnNP) were selected for this study. Four synthesis methods were tested to produce distinct size populations of polymer-coated ZnNP, and all utilized water as the solvent to promote sustainable, green chemistry. The antibacterial activity of ZnNP was assessed in two agriculturally relevant bacteria strains: Escherichia coli and Bacillus cereus . To further examine the effects of ZnNP on bacterial cells, reactive oxygen species (ROS) generation was measured via hydrogen peroxide (H 2 O 2 ) production. The bacteria's incubation temperature was also altered to assess bacterial growth and susceptibility after exposure to ZnNP. The ZnNP from the smaller size population inhibited the most growth across bacterial strains, assays, and incubation temperatures. Increased antibacterial effects and ROS production were observed after incubation at a higher temperature. These results indicate that the deliberately designed nanoparticles are potentially valuable in microbial control and offer promising solutions for the future of healthy agricultural systems.

Purpose: Chronic suppurative otitis media (CSOM) is a prominent contributor to preventable hearing loss globally. Probiotic therapy has attracted research interest in human infectious and inflammatory disease. As the most prevalent probiotic, the role of Lactobacillus in CSOM remains poorly defined. This study aimed to investigate the antipathogenic effects and underlying mechanism of Lactobacillus on CSOM., Methods: RNA sequencing of granulation of middle ear cavity from CSOM patients and lavage fluid of middle ear from normal volunteer was conducted. Human middle ear epithelial cells (HMEEC) and rats infected with Bacillus cereus ( B. cereus ) and Staphylococcus aureus ( S. aureus ) were used for CSOM constructing. Western blot, qPCR and Vybrant™ Alexa Fluor™ 488 lipid raft labeling were performed to explore the possible molecular mechanism by which lipid raft linker (RFTN1) regulates lipid raft/toll-like receptor 4 (TLR4). ELISA and HE staining was utilized to evaluate the effect of Lactobacillus on the progression of CSOM in vivo ., Results: Based on RNA Sequence analysis, a total of 3646 differentially expressed genes (1620 up-regulated and 2026 down-regulated) were identified in CSOM. RFTN1 was highly expressed in CSOM. Inhibition of RFTN1 not only reduced the inflammatory response of CSOM but also suppressed the formation of lipid rafts. Further investigation revealed that RFTN1 inhibition could reduce the expression of TLR4, which also localizes to the lipid rafts. TLR4 responds to RFTN1-mediated inflammatory responses in CSOM. We treated the CSOM model with Lactobacillus , which has great potential for alleviating the inflammatory response, and found that Lactobacillus attenuated the development of CSOM by reducing RFTN1 and TLR4 expression., Conclusion: In conclusion, these findings suggest a crucial role for Lactobacillus in alleviating CSOM progression and uncovered the molecular mechanism involving Lactobacillus -regulated inhibition of the RFTN1-lipid raft-TLR4 signaling pathway under CSOM conditions., Competing Interests: The authors declare no competing interests., (© 2024 Liu et al.)

This study was conducted to evaluate the sufficiency of food safety practices in a catering company. The presence of some pathogenic and indicator bacteria was monitored in the samples collected from raw materials, food, food contact surfaces and workers' hands and various steps of the tas kebab (a Turkish meat stew) and salad processing lines. Bacillus cereus was found in ready-to-eat (RTE) tas kebab and RTE salad, while Listeria monocytogenes was isolated from RTE salad. Furthermore, it was observed that RTE salad contained coagulase-positive Staphylococcus aureus without staphylococcal enterotoxin production. The swab samples obtained from cutting board surfaces, knives and workers' hands contained high counts of total aerobic bacteria and some samples were contaminated with coliforms and coagulase-positive/negative staphylococci. The presence of B. cereus and L. monocytogenes in RTE foods is a serious threat to public health, especially in the catering business. Preventing the presence of toxin-producing bacteria in RTE food is a fundamental action. Also, the occurrence of L. monocytogenes in RTE salad and B. cereus in RTE tas kebab/salad samples showed insufficient cleaning/disinfection practices. As a result, hygiene practices and regular monitoring in the catering business are necessary for food safety.

Biovanillin production by a wild strain of Bacillus cereus NCIM-5727 is studied using eugenol as the precursor aiming to achieve maximum vanillin productivity. Based on shake flask optimization, molar yield and global volumetric productivity of vanillin reached up to 71.2% (6.6 gL−1) and 0.18 g(Lh)−1, respectively, at 36 h by resting cells of B. cereus NCIM-5727 at the optimum cell concentration of 3 gL−1 using eugenol concentration of 10 gL−1 at 37 ºC, buffer pH 7.0, buffer volume 10%, and shaking speed 180 rpm. Furthermore, small-scale optimization in a bioreactor at the controlled aeration rate of 0.5 Lmin−1, agitation rate of 210 rpm, and pH 7.0 enhanced the global volumetric productivity of vanillin up to 0.28 g(Lh)−1 at 25 h of bioconversion. The highest vanillin molar yield (75.2%) is reported using resting cells of B. cereus NCIM-5727 upon eugenol biotransformation and found stable for 10 h. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxygen and air plasma are useful for inactivating B. cereus in soy powder. • Oxygen plasma achieved greater efficacy in B. cereus inactivation. • Inactivation correlated with the formation of ionized radicals. • The Weibull model fitted the experimental data well. Cold plasma (CP) technology is a promising alternative to thermal treatments for the microbial decontamination of foods with low-water activity. The aim of this work is study the application of low-pressure CP (0.35 mbar) for the inactivation of Bacillus cereus in a soybean powder matrix using O₂ and synthetic air as ionizing gases. The parameters tested were an input power of 100, 200 and 300 W and an exposure time of 10 to 30 min. The excited reactive species formed were monitored by optical emission spectroscopy, and survival data were analyzed using the Weibull mathematical model. Treatments with both gases were effective in inactivating B. cereus. Air plasma resulted in a maximum 3.71-log reduction in bacterial counts at 300 W and 30 min, while O 2 plasma showed the strongest inactivation ability, achieving levels higher than 5 log cycles at 300 W and > 25 min. This is likely due to the strong antimicrobial activity of oxygen-derived radicals together with carbon monoxide as an oxidation by-product. In addition, the Weibull distribution function accurately modeled the inactivation of B. cereus. Cold plasma technology is a promising approach for the decontamination of bacteria in low-water activity foods. [ABSTRACT FROM AUTHOR]

This study was conducted in the greenhouse of Plant Protection Department at College of Agriculture, Kufa University to determine the effect of three types of bacteria including (B. firmus, B. cereus; B. simplex). Results were giving the highest average length of plant, which reached 16.66 cm, while the lowest length reached 10.66 cm in the treatment of M. incognita + Copra and there were no significant difference between most of the treatments to improve plant growth development with three different types of bacteria that treated with cucumber seeds without negative effect on plant growth, while the highest average weight of the root system was 8.46 grams in the treatments of B. simplex, B. cereus, B. firmus together+ Nigrosine. The lowest weight of roots system was 0.57 grams with control Copra treated and there was a clear significant difference between them at the level of the average wet weight of cucumber plants and root system of the two cucumber varieties, B. simplex, B. cereus, B. firmus + Nigrosin treatment was superior to the rest of the treatments in giving to improve cucumber plant growth development compared to abamectin treatment that used as standard to compared the results for three types of bacteria. Results showed that the M. incognita + B. simplex treatment was superior by reducing the number of eggs / cucumber plant and juveniles (by 500 cm3 of soil) compared to control treatment with root-knot nematode only for both number of eggs/cucumber plant and juveniles. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Biotecnología is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Surface‐enhanced Raman scattering (SERS) is a powerful tool for constructing biomolecular fingerprints, which play a vital role in differentiation of bacteria. Due to the rather subtle differences in the SERS spectra among different bacteria, artificial intelligence is usually adopted and enormous amounts of spectral data are required to improve the differentiation efficiency. However, in many cases, large volume data acquisition on bacteria is not only technical difficult but labour intensive. It is known that surface modification of SERS nanomaterials can bring additional dimensionality (difference) of the SERS fingerprints. Here in this work, we show that the concept could be used to improve the bacteria differentiation efficiency. Ag NPs were modified with 11‐mercaptoundecanoic acid, 11‐mercapto‐1‐undecanol, and 1‐dodecanethiol to provide additional dimensionality. The modified NPs then were mixed with cell lysate from different strains of Bacillus cereus (B. cereus). Even by applying a simple PCA process to the resulting SERS spectra data, all the three modified Ag NPs showed superior differentiation results compared with bare Ag NPs, which could only separate Staphylococcus aureus (S. aureus) and B. cereus. It is believed that the multidimensional SERS could find great potential in bacteria differentiation. [ABSTRACT FROM AUTHOR]

The pre-isolated B. cereus had shown better β-cypermethrin resistance at 100 mg L−1 dosage in the Mineral Salt Medium (MSM). Hence, it was applied for the biodegradation study on MSM. The GC-MS analysis revealed that the B. cereus had the potential to degrade β-cypermethrin and metabolize it into six predominant less or nontoxic components (benzene, 1-ethyl−3-methyl-, ethanethiol, 2-(dimethylamino)-, 1-(2-acetoxyethyl)-3,6-diazahomoadamantan-9-one, silane, 9-anthracenyltrimethyl-, 1-(3-hydroxy-3-methylbutyl)-3,6-,fumaric acid). Based on this biodegradation potential, four experimental groups, namely A, B, C, D and control, were framed and the biodegradation potential of B. cereus on β-cypermethrin and interaction with P. excavates were studied. Group C, which includes B. cereus and 10 P. excavates under β-cypermethrin stress excavates positive survival interaction. It was confirmed by the presence of metabolites such as benzene, 1-ethyl-3-methyl-, ethanethiol, 2-(dimethylamino)- and 1-(2-acetoxyethyl)-3,6-diazahomoadamantan-9-one, in P. excavates. Furthermore, these were similar to the metabolites of β-cypermethrin degraded by B. cereus. These results conclude that the biodegradation potential of B. cereus can protect the life of P. excavates from β-cypermethrin toxicity and thus, can support the balancing of soil fertility, structure and soil biotas such as flora and fauna. Abbreviations: MSM: mineral salt medium; g: gram; kg: kilogram; GC-MS: gas chromatography–mass spectrometry; mg L−1: milligram per litter; mL: milliliter; mg: milligram; min: minutes; MSTFA:N-methyl-N-(trimethylsilyl) trifluoroacetamide; EC: electric conductivity; N: nitrogen; P: phosphate; K: potassium; ECD: electron capture detector; OC: organic carbon; LB: Luria–Bertani; ºC: temperature in Celsius; pH: potential of hydrogen; R.T: retention time; NIST: National Institute of Standards and Technology; rpm: rotations per minute; TNAU: Tamil Nadu Agriculture University [ABSTRACT FROM AUTHOR]