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Abstract Biofilm formation by Bacillus cereus strains is now recognized as a systematic contaminaron mechanism in foods; the aim of this study was to evaluate the production of submerged and interface biofilms in strains of B. cereus group in different materials, the effect of dex-trose, motility, the presence of genes related to biofilms and the enterotoxigenic profile of the strains. We determine biofilm production by safranin assay, motility on semi-solid medium, toxin gene profiling and genes related to biofilm production by PCR in B. cereus group iso-lated from food. In this study, we observe strains used a higher production of biofilms in PVC; in the BHI broth, no submerged biofilms were found compared to phenol red broth and phenol red broth supplemented with dextrose; no strains with the ces gene were found, the enterotoxin profile was the most common the profile that includes genes for the three enterotoxins. We observed a different distribution of tasA and sipW with the origin of isolation of the strain, being more frequent in the strains isolated from eggshell. The production and type of biofilms are differential according to the type of material and culture medium used.
Resumen La formación de biopelículas por cepas de Bacillus cereus es reconocida como un mecanismo de contaminación sistemática en alimentos; el objetivo del estudio fue evaluar la producción de biopelículas sumergidas y de superficie en cepas del grupo de Bacillus cereus en diferentes materiales, el efecto de la dextrosa, la motilidad, la presencia de genes relacionados a biopelículas y el perfil enterotoxigénico de las cepas. Determinamos la producción de biopelículas por el ensayo de safranina, motilidad en medio sólido, perfil enterotoxigénico y genes relacionados a producción de biopelículas por PCR en aislados del grupo de Bacillus cereus de alimentos. En este estudio, observamos en las cepas utilizadas una alta producción de biopelículas en PVC; en caldo BHI, no se encontraron biopelículas sumergidas en comparación con el caldo rojo de fenol y caldo rojo de fenol suplementando con dextrosa; no se encontraron cepas con el gen ces, el perfil de enterotoxinas más común fue el perfil que incluía los genes de las tres enterotoxinas, también observamos una distribución diferente de tasA y sipW con relación al origen de la cepa, siendo más frecuente estos genes en las cepas aisladas de huevos. La producción y el tipo de biopelículas es diferente de acuerdo con el tipo de material y el medio de cultivo utilizado.
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Introduction: Infective endocarditis (IE) is an infectious process of the cardiac endothelium, often related to the use of pacemakers and valve prostheses, which may facilitate microorganism" proliferation. Case Report: In this article, we describe the case of an 81-year-old man with infective endocarditis due to Bacillus Cereus related to the use of a pacemaker and perform a brief literature review. Discussion: Bacillus Cereus is a Gram-positive, aerobic, spore-forming, large, and generally motile bacterium that constitutes a rare cause of endocarditis, but few cases like this are described in the literature. Conclusion: Determining the etiology of IE through culture-guided methods plays a pivotal role in selecting appropriate antibiotic treatment. Maintain a high clinical suspicion for IE is paramount, especially when fever arises in patients with cardiac devices after surgical or dental procedures.
Introdução: A endocardite infecciosa é um processo infeccioso do endotélio cardíaco, muitas vezes relacionado ao uso de marca-passos e próteses valvares, que pode facilitar a proliferação de microrganismos. Relato de Caso: Neste artigo descrevemos o caso de um homem de 81 anos com endocardite infecciosa por Bacillus Cereus relacionada ao uso de marca-passo e realizamos uma breve revisão da literatura. Discussão: Bacillus Cereus é uma bactéria Gram-positiva, aeróbia, formadora de esporos, grande e geralmente móvel, que constitui uma causa rara de endocardite, com poucos casos descritos na literatura. Conclusão: A determinação da etiologia da EI através de métodos guiados por cultura desempenha um papel fundamental na seleção do tratamento antibiótico apropriado. Manter alta suspeita clínica de EI é fundamental, principalmente quando surge febre em pacientes portadores de dispositivos cardíacos após procedimentos cirúrgicos ou odontológicos.
Subject(s)
Humans , Male , Aged, 80 and over , Pacemaker, ArtificialABSTRACT
AIM: To analyze the clinical characteristics and antibiotic sensitivity of traumatic endophthalmitis caused by Bacillus cereus and discuss the early diagnosis and treatment measures.METHODS: The data of 15 patients(15 eyes)with Bacillus cereus endophthalmitis admitted to the Eye Trauma Center of Shaanxi Provincial Eye Hospital from January 2019 to December 2021 were collected. The injury time, injury condition, preoperative visual acuity, corrected visual acuity in the last follow-up, operation method, bacterial culture and drug sensitivity test results were recorded.RESULTS: Among the 15 patients(15 eyes), 5 eyes with simple corneal perforating wound were treated with wound debridement and suture combined with intraocular antibiotic injection. And another 10 eyes with penetrating injuries combined with traumatic cataract and intraocular foreign bodies were treated with debridement, cataract extraction, removal of intraocular foreign bodies, vitrectomy combined with silicone oil tamponade and intraocular antibiotic injection. Among the 15 patients, 11 patients(73%)were treated effectively and the eyeball was preserved, and 4 patients(27%)were treated ineffectively and ocular evisceration was performed. Among the 11 patients with eyeball retention, 1(9%)had decreased vision, 1(9%)had unchanged vision, 4(36%)had improved vision by 1 level, and 5(45%)had improved vision by 2 levels, and the postoperative visual acuity was significantly improved. Correlation analysis showed that the course of disease was negatively correlated with corrected visual acuity(rs=-0.762, P=0.001). The cultures of vitreous humor and aqueous humor samples of patients were all grown in Bacillus cereus, and susceptibility tests were sensitive to vancomycin.CONCLUSIONS: Vancomycin is an effective drug for the treatment of Bacillus cereus endophthalmitis. Vitrectomy combined with silicone oil tamponade and intravitreal injection of vancomycin are effective method for the treatment of Bacillus cereus endophthalmitis.
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Bacillus cereus is a common foodborne pathogen. Accidently eating food contaminated by B. cereus will cause vomiting or diarrhea, and even death in severe cases. In the present study, a B. cereus strain was isolated from spoiled rice by streak culture. The pathogenicity and drug resistance of the isolated strain were analyzed by drug sensitivity test and PCR amplification of virulence-associated gene respectively. Cultures of the purified strain were injected intraperitoneally into mice to examine their effects on intestinal immunity-associated factors and gut microbial communities, to provide references for the pathogenic mechanism and medication guidance of these spoilage microorganisms. The results showed that the isolated B. cereus strain was sensitive to norfloxacin, nitrofurantoin, tetracycline, minocycline, ciprofloxacin, spectinomycin, clindamycin, erythrocin, clarithromycin, chloramphenicol, levofloxacin, and vancomycin, but resistant to bactrim, oxacillin and penicillin G. The strain carries seven virulence-associated genes including hblA, hblC, hblD, nheA, nheB, nheC and entFM, which are involved in diarrhea-causing toxins production. After infecting mice, the isolated B. cereus strain was found to cause diarrhea in mice, and the expression levels of immunoglobulins and inflammatory factors in the intestinal mucosae of the challenged mice were significantly up-regulated. Gut microbiome analysis showed that the composition of gut microbial community in mice changed after infection with B. cereus. The abundance of the uncultured_bacterium_f_Muribaculaceae in Bacteroidetes, which is a marker of body health, was significantly decreased. On the other hand, the abundance of uncultured_bacterium_f_Enterobacteriaceae, which is an opportunistic pathogen in Proteobacteria and a marker of dysbacteriosis, was significantly increased and was significantly positively correlated with the concentrations of IgM and IgG. These results showed that the pathogenic B. cereus carrying diarrhea type virulence-associated gene can activate the immune system by altering the composition of gut microbiota upon infection.
Subject(s)
Animals , Mice , Bacillus cereus/metabolism , Food Microbiology , Immunity, Mucosal , Diarrhea , Microbiota , Enterotoxins/geneticsABSTRACT
@#Objective To isolate and identify the pathogenic bacteria in Tongliao area,Inner Mongolia Autonomous Region,China in 2019 and determine the virulence gene distribution and pathogenicity.Methods Three Gram positive isolates,FL1,FL2 and FL3,from the clinical specimens in Tongliao area were subjected to biochemical test,drug sensitivity test,16S rDNA sequencing,virulence gene test and pathogenicity test.Results Bio-chemical test proved the three isolates as Bacillus cereus. The strains FL1 and FL2 from bovine origin were resistant to penicillin and carbamazillin,while the strain FL3 from horse origin to Cefradine. Strains FL1 and FL2 showed the closest relationship to the isolate(KR063181. 1)from Hunan,China,while strain FL3 to the isolate(HM104658. 1)from Shandong,China. However,strain FL3 showed relatively far relationship to strains FL1 and FL2. All the distributions of eight virulence genes of B.cereus were observed in the three strains,while the distributions of four virulence genes of B.anthracoides were different. All the three isolates showed pathogenicity.Conclusion All the three isolates were pathogenic B.cereus,which showed a certain drug resistance. However,there were differences in virulence gene distri-bution between bovine and equine B.cereus.
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Aim: This study was carried out to investigate the antibacterial properties and efficacy of mango (Mangifera indica) leaf extracts on some clinical isolates as test rganisms. Study Design: The study employed statistical analysis of the data and interpretationPlace and Duration of Study: Young and mature mango leaves were collected from the Botanical Garden, Kenule Beeson Saro-Wiwa Polytechnic, Bori, Nigeria, and taken to the laboratory for analyses. Methodology: The samples were dried in an oven at 80oC for 3 days. Thereafter, 50 g of each ground mango leaf (young and mature leaves) were soaked separately in 500 ml of water, ethanol (95% v/v), and acetic acid (99.9% v/v) respectively for another 3 days. The soaked materials were filtered through Whatman No. 1 filter paper into sterile beakers and evaporated to dryness in a water bath at 80oC. The dried extracts obtained were reconstituted with water at concentrations of 100, 75, 50, and 25 mg/ml. Test organisms, Escherichia coli, Staphylococcus aureus, Salmonella typhi, Proteus mirabilis, Bacillus cereus, and Pseudomonas aeruginosa were obtained after proper laboratory screening of isolates from the diagnostic laboratory of the Rivers State University Teaching Hospital, Port Harcourt, Nigeria, for confirmation of identity and storage in universal bottles in a refrigerator. Sensitivity tests were carried out with the agar well diffusion method against the test organisms, using tetracycline as the standard control drug, with cultures incubated accordingly. The measured zones of inhibition were compared with the controls and interpreted as resistant, intermediate, or susceptible to mango extracts in accordance with the interpretive guidelines published by the National Committee for Clinical Laboratory Standards (NCCLS). Assay for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was also carried out. Results: Results obtained showed that acetic acid young leaf extract at 100mg/ml produced 50 % susceptibility and 50 % intermediate response of test bacterial species. Generally, at 100 mg/ml, acetic acid young leaf extracts yielded 50% susceptibility and 50% intermediate response among both Gram-positive and Gram-negative bacteria. Ethanolic extracts gave 100% intermediate sensitivity of Gram-negative species and 50% each of resistant and intermediate response in Gram-positive forms. Aqueous extracts also produced no susceptibility among the test organisms as there was 100% resistance. Extracts of mature mango leaves of all solvents and at all concentrations used yielded no susceptibility response among the test bacterial species on the NCCLS scale. Minimum inhibitory and bactericidal concentrations were found to range from 25 mg/ml to 50 mg/ml. Additionally, it was observed that the sensitivity of organisms to mango extracts increased with concentration.Conclusion: In conclusion, acetic acid has a better extracting potential than ethanol and water as a solvent for the extraction of mango parts. More so, young mango leaves extracted with acetic acid possess higher broad-spectrum antibacterial properties than the mature mango leaves extracted from the same plant. It is therefore recommended that young mango leaves, extracted with acetic acid, be used for the treatment of microbial infections at concentrations not below 50 mg/ml.
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Riboflavin is an essential, water-soluble vitamin (B2) and a component of basic cellular metabolism. The aim of the present study is to isolate and characterize riboflavin producing bacteria from different food sources. Ten different riboflavin enriched food sources were collected from Vellore district. Totally 72 bacterial strains were isolated and cultured on nutrient agar plates. Out of these, 43 strains were identified as riboflavin producers. Isolated bacterial strains HDS27, HDS07, HDS14, HDS18, HDS38 and HDS54 isolated from milk, mushroom, spinach, lamb kidney, beef liver and mackerel fish were found to be potent riboflavin producers. Based on morphological, biochemical and molecular characterization, the potent strains were identified as Lactobacillus plantarum (HDS27), Bacillus cereus (HDS07), Delftia tsuruhatensis (HDS14), Citrobacter freundii (HDS18), Enterobacter cloacae (HDS38) and Bacillus cereus (HDS54). The selected potent isolates HDS27 from milk and HDS07 from mushroom showed a maximum riboflavin production of 3.69 mg/L and 2.9mg/L respectively. The present study explores the riboflavin producing novel bacteria from different food sources. This is the first report that the Enterobacter cloacae isolated from beef liver, Delftia tsuruhatensis from spinach and Citrobacter freundii from lamb kidney has the ability to produce riboflavin. These potent strains could be a better starter for substituting the conventional bacteria for large scale production of riboflavin in industry.
Subject(s)
Riboflavin , Bacillus cereus , Citrobacter freundii , Lactobacillus plantarumABSTRACT
Objective:To study the clinical features, diagnosis and treatment of Bacillus cereus sepsis in premature infants.Methods:From February 2011 to February 2021, 10 cases of Bacillus cereus sepsis in premature infants admitted to the Department of Neonatology of our hospital were retrospectively analyzed.Results:The 10 cases of premature infants with Bacillus cereus sepsis included 5 males and 5 females, with gestational age 27 +2~35 +2 weeks, birth weight 940~2 430 g and the age of onset 7~35 days. At the beginning, all the infants showed lethargy and recurrent apnea as the onset symptoms. 8 cases had gray color skin, 7 cases had fever, 7 cases experienced septic shock, 5 cases had neonatal seizures and 4 cases showed abdominal distension. 7 cases were complicated with purulent meningitis and 3 cases with necrotizing enterocolitis. 9 cases had significantly decreased white blood cells and platelets and significantly increased C-reactive protein and procalcitonin at the onset. Among the 7 cases of purulent meningitis, 5 cases had multiple encephalomalacia. During follow-up of all the infants, 4 cases died, 3 cases cured and 3 cases survived with severe neurological sequelae. Conclusions:Bacillus cereus sepsis is a serious infectious disease for premature infants with acute onset, rapid progress and high mortality. Complication of purulent meningitis and serious neurological sequelae are common.
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The effects of Calcium (Ca+²) on virulence and some parameters should be analyzed in this study. Pseudomonas aeruginosa Gram (-) and Bacillus cereus Gram (+) were used. Both bacteria are soil bacteria. In this study; the effect of Ca+² on protease, amylase, LasB elastolytic assay, H2O2, pyorubin and biofilm on metabolites of these bacteria were investigated during 24 hour time. In this study, the effect of Ca+² on the production of some secondary metabolites on P. aeruginosa and B. cereus was investigated and presented for the first time by us.
Os efeitos do cálcio (Ca+²) na virulência e alguns parâmetros devem ser analisados neste estudo. Pseudomonas aeruginosa Gram (-) e Bacillus cereus Gram (+) foram usados. Ambas as bactérias são bactérias do solo. Neste estudo, o efeito do Ca+² sobre a protease, amilase, ensaio elastolítico LasB, H2O2, piorubina e biofilme nos metabólitos dessas bactérias foram investigados durante 24 horas. Neste estudo, o efeito do Ca+² na produção de alguns metabólitos secundários em P. aeruginosa e B. cereus foi investigado e apresentado pela primeira vez por nós.
Subject(s)
Bacillus cereus/enzymology , Bacillus cereus/chemistry , Bacillus cereus/virology , Calcium/analysis , Pseudomonas aeruginosa/enzymology , Pseudomonas aeruginosa/chemistry , Pseudomonas aeruginosa/virologyABSTRACT
Abstract The effects of Calcium (Ca+2) on virulence and some parameters should be analyzed in this study. Pseudomonas aeruginosa Gram (-) and Bacillus cereus Gram (+) were used. Both bacteria are soil bacteria. In this study; the effect of Ca+2 on protease, amylase, LasB elastolytic assay, H2O2, pyorubin and biofilm on metabolites of these bacteria were investigated during 24 hour time. In this study, the effect of Ca+2 on the production of some secondary metabolites on P. aeruginosa and B. cereus was investigated and presented for the first time by us.
Resumo Os efeitos do cálcio (Ca+2) na virulência e alguns parâmetros devem ser analisados neste estudo. Pseudomonas aeruginosa Gram (-) e Bacillus cereus Gram (+) foram usados. Ambas as bactérias são bactérias do solo. Neste estudo, o efeito do Ca+2 sobre a protease, amilase, ensaio elastolítico LasB, H2O2, piorubina e biofilme nos metabólitos dessas bactérias foram investigados durante 24 horas. Neste estudo, o efeito do Ca+2 na produção de alguns metabólitos secundários em P. aeruginosa e B. cereus foi investigado e apresentado pela primeira vez por nós.
ABSTRACT
The effects of Calcium (Ca+2) on virulence and some parameters should be analyzed in this study. Pseudomonas aeruginosa Gram (-) and Bacillus cereus Gram (+) were used. Both bacteria are soil bacteria. In this study; the effect of Ca+2 on protease, amylase, LasB elastolytic assay, H2O2, pyorubin and biofilm on metabolites of these bacteria were investigated during 24 hour time. In this study, the effect of Ca+2 on the production of some secondary metabolites on P. aeruginosa and B. cereus was investigated and presented for the first time by us.
Os efeitos do cálcio (Ca+2) na virulência e alguns parâmetros devem ser analisados neste estudo. Pseudomonas aeruginosa Gram (-) e Bacillus cereus Gram (+) foram usados. Ambas as bactérias são bactérias do solo. Neste estudo, o efeito do Ca+2 sobre a protease, amilase, ensaio elastolítico LasB, H2O2, piorubina e biofilme nos metabólitos dessas bactérias foram investigados durante 24 horas. Neste estudo, o efeito do Ca+2 na produção de alguns metabólitos secundários em P. aeruginosa e B. cereus foi investigado e apresentado pela primeira vez por nós.
Subject(s)
Pseudomonas , Bacillus cereus , Pseudomonas aeruginosa , Calcium , Hydrogen PeroxideABSTRACT
ABSTRACT In this study, B. cereus was detected in dialysis fluids within international parameters (ultrapure - maximum limit of 0.1 CFU/mL for heterotrophic bacteria count) by analyzing the pellet obtained through the centrifugation method. We also investigated the ability of the B. cereus isolate to form a biofilm at different temperatures, the production of virulence factors, and the susceptibility to commercial antimicrobial agents. This study demonstrated a high ability of B. cereus to persist in the hemodialysis system, which can be explained by its broad ability to produce a biofilm at 25 °C, its relevant production of virulence factors, such as β-hemolysin, lecithinase and cereulide, and its important resistance pattern to antimicrobial drugs. In conclusion, these new findings expand the understanding that this microorganism should not be neglected and new methods for tracking it should be considered.
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Continuous occurrence of heavy metals is a major cause of environmental pollution due to its toxic effects. At minimum concentrations, these metals are highly reactive and can gather in the food chains and food web, causing major dangers to public health concerns. Soil samples were collected from Paharang drain, Faisalabad. Cadmium tolerant bacteria were isolated and evaluated for their MIC against Cd. The isolated bacterial strain GCFSD01 showed MIC value upto 30 mM/L. The bacterial strain with the highest resistance against Cd was selected for further study. Molecular characterization of bacterial isolate GCFSD01 was performed by 16S rRNA which confirmed it as Bacillus cereus. Optimum growth conditions of bacterial strain were also evaluated. Strain GCFSD01 showed optimum growth at pH 7 and 37 °C temperature. Our result revealed that B. cereus strain GCFSD01 reduced 61.3% Cd after 48 hrs. Multiple metal tolerance and Cd reduction by B. cereus indicate its potential for further use for decontamination of polluted soil.
A ocorrência contínua de metais pesados é uma das principais causas de poluição ambiental devido aos seus efeitos tóxicos. A contaminação por metais pesados representa um grande risco para todas as formas de vida encontradas no meio ambiente. Em concentrações mínimas, esses metais são altamente reativos e podem se acumular nas cadeias alimentares e na cadeia alimentar, causando grandes perigos às preocupações com a saúde pública. Amostras de solo foram coletadas no esgoto de Paharang, Faisalabad. Bactérias tolerantes ao cádmio foram isoladas da amostra coletada pelo método da placa de ágar. As colônias separadas individuais selecionadas foram avaliadas quanto às suas concentrações inibitórias mínimas contra Cd. A cepa bacteriana isolada GCFSD01 apresentou valores de CIM de 30 mM/L. A colônia bacteriana que apresentou maior resistência contra o Cd foi selecionada para identificação. Após seleção da maior colônia bacteriana resistente ao Cd, coloração de Gram e diferentes testes bioquímicos foram realizados para a caracterização da bactéria isolada. A caracterização molecular do isolado bacteriano GCFSD01 foi realizada por PCR 16S rRNA confirmando a presença de Bacillus cereus. Após a identificação molecular, as condições ótimas de crescimento da cepa bacteriana também foram verificadas. A cepa GCFSD01 apresentou crescimento ótimo em pH 7 e temperatura de 37 °C. Nosso resultado revelou que a cepa de B. cereus GCFSD01 reduziu 61,3% de Cd após 48 horas. A tolerância a múltiplos metais e a redução de Cd por B. cereus indicam seu potencial para uso posterior na descontaminação do solo poluído.
Subject(s)
Soil Pollutants/toxicity , Bacillus cereus/genetics , Cadmium/toxicity , Industrial Effluents/adverse effects , Metals, Heavy/analysis , Soil , Soil Microbiology , Biodegradation, Environmental , RNA, Ribosomal, 16S/geneticsABSTRACT
Objective:To investigate the causes of strong pathogenicity of Bacillus cereus ( B. cereus) in a mouse model of B. cereus endophthalmitis and the factors that might be related to the prognosis of the disease. Methods:C57BL/6J mice aged 6-8 weeks were injected with 1 μl PBS solution containing 100 CFU B. cereus into the vitreous cavity to construct traumatic endophthalmitis model, and a control group was set up by injecting the contralateral eyeball with 1 μl sterile PBS. A mouse model of Staphylococcus epidermidis ( S. epidermidis) endophthalmitis was constructed in the same way as disease control group. Real-time fluorescent quantitative polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) were used to detect the levels of inflammatory cytokines at different time points. Histology, electroretinogram and transmission electron microscopy were used to detect the progression of endophthalmitis and retinal function at different time points. Results:B. cereus grew significantly faster than S. epidermidis in the eyes of C57BL/6 mice and gradually moved to the cornea 12 h after infection. The results of transmission electron microscopy showed that many more B. cereus were found in the iris with sparse pigment particles, while S. epidermidis could not be detected in the anterior segment after infection. The electroretinogram results showed that the amplitude of A wave and B wave of mice with B. cereus endophthalmitis decreased significantly 6 h after infection, and the B wave could not be detected 12 h after infection. Moreover, the amplitude reduction at different time points was significantly larger than that in the S. epidermidis endophthalmitis group. Histological examination found that compared with the S. epidermidis endophthalmitis group, the mice with B. cereus endophthalmitis had significantly increased inflammatory cells in the anterior chamber and vitreous cavity with a higher degree of infiltration, which was more destructive to the tissue structure. ELISA results showed that the activity of myeloperoxidase (MPO) was significantly stronger in the B. cereus endophthalmitis group than in the S. epidermidis endophthalmitis group, suggesting that a much more severe inflammation was induced. The expression of IL-6, TNF-α and IL-1β at the transcription and protein levels in the mouse model of B. cereus endophthalmitis were significantly higher than those in the mice with S. epidermidis endophthalmitis. Conclusions:B. cereus could induce severe endophthalmitis and tissue destruction in the eye due to its rapid growth and migration ability, which was an important factor leading to vision loss.
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RESUMEN La planta Lippia origanoides ha sido ampliamente estudiada debido al efecto antimicrobiano y antifúngico que poseen sus extractos y aceites esenciales, los cuales han sido probados contra un gran número de microorganismos patógenos. Sin embargo, es escasa la literatura que registra la diversidad de bacterias endófitas asociadas a esta especie de plantas. El objetivo del trabajo fue evaluar in vitro la capacidad de promoción de crecimiento vegetal de bacterias endófitas de Lippia origanoides en el municipio de Sincelejo -Sucre, Colombia. En este estudio se aislaron bacterias endófitas en medio de cultivo agar R2A a partir de diferentes tejidos, se evaluó la densidad poblacional (UFC/g de tejido) por conteo en superficie y la promoción de crecimiento vegetal de forma cualitativa en medios selectivos específicos. Se observaron diferencias significativas para la densidad poblacional de bacterias endófitas respecto al tipo de tejido, con mayores valores en la raíz (2,0 x 1010/g raíz), seguido del tallo (1,3 x 1010/g tallo) y hojas (9,2 x 109/g hoja). Se obtuvieron un total de 20 bacterias endófitas, los cuales dos mostraron capacidad solubilizadora de fosfato, fijación biológica de nitrógeno, producción de sideróforos y ACC desaminasa. Los morfotipos TLO5 y RLO4 fueron identificados molecularmente como Bacillus cereus, mostrando buenos resultados de promoción de crecimiento vegetal.
ABSTRACT The Lippia origanoides plant has been widely studied due to the antimicrobial and antifungal effect of its extracts and essential oils, which have been tested against a large number of pathogenic microorganisms. However, there is little literature that records the diversity of endophytic bacteria associated with this plant species. The objective of the work was to evaluate in vitro the plant growth promotion capacity of endophytic Lippia origanoides bacteria in the municipality of Sincelejo-Sucre, Colombia. In this study, endophytic bacteria were isolated in R2A agar culture medium from different tissues, population density (CFU / g of tissue) was evaluated by surface counting and the promotion of plant growth qualitatively in specific selective media. Significant differences were observed for the population density of endophytic bacteria regarding tissue type, with higher values in the root (2.0 x 1010 / g root), followed by the stem (1.3 x 1010 / g stem) and leaves (9.2 x 109 / g sheet). A total of 20 endophytic bacteria were obtained, which two showed phosphate solubilizing capacity, biological nitrogen fixation, production of siderophores and ACC deaminase. The TLO5 and RLO4 morphotypes were molecularly identified as Bacillus cereus, showing good results in promoting plant growth.
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Abstract Bacillus cereus is a gram positive microorganism commonly involved in gastrointestinal infection but capable of causing severe infections and bacteremia. We describe here a case of bacteremia caused by B. cereus in a previously healthy young woman admitted to the intensive care unit following emergency surgery due to a penetrating abdominal stab wound and subsequent hepatic lesion. She developed fever during admission and cultures were taken. B. cereus was isolated in blood and hepatic fluid collection cultures. Treatment was adjusted according to the isolate, with good clinical results. It is important to highlight the pathogenic potential of this microorganism and not underestimate it as a contaminant when it is isolated from blood samples.
Resumen Bacillus cereus es un microorganismo gram positivo comúnmente involucrado en infecciones gastrointestinales, pero capaz de causar infecciones graves y bacteriemia. Presentamos un caso de bacteriemia por B. cereus en una mujer joven previamente sana que ingresa en la unidad de cuidados intensivos luego de una cirugía de emergencia, debido a una herida abdominal por arma blanca con lesión hepática. La paciente desarrolla fiebre durante la internación, por lo que se toman cultivos. Se aísla B. cereus en hemocultivos y material de colección hepática. Se ajusta el tratamiento según los hallazgos, con buena evolución clínica. Esta comunicación ilustra una fuente poco común de bacteriemia por B. cereus. Asimismo, destaca el potencial patogénico de este microorganismo, cuyo hallazgo en muestras de sangre no siempre debe conducir a su rápida desjerarquización como contaminante.
Subject(s)
Adult , Female , Humans , Bacillus cereus/isolation & purification , Wounds, Stab/microbiology , Gram-Positive Bacterial Infections/microbiology , Bacteremia/microbiology , Abdominal Injuries/microbiology , Wounds, Stab/blood , Gram-Positive Bacterial Infections/blood , Bacteremia/blood , Abdominal Injuries/bloodABSTRACT
The degradation of textile dyes using microbes has been recently identified as most promising, cost effective,and eco-friendly technique than any physiochemical techniques. On this backdrop, a potential Reactive Black5 dye degrading bacterium was isolated from effluent sediment samples of a textile industry, Salem district,Tamil Nadu, India which was identified as a Bacillus cereus SKB12 based on morphological and biochemicalmethods. This bacterium exhibited promising dye degradation of Reactive Black 5 which was initiatedfrom first hours of lag phase and showed its maximum dye degradation of 88.7% at the end decline growthphase (144 hours). Furthermore, this strain revealed the synthesis of laccase, veratryl alcohol oxidase, ligninperoxidase, polyphenol oxidase, and azoreductase enzymes with the presence of Reactive Black 5 dye. Theseoverall observations proved that this strain, B. cereus SKB12 has the possibility to use as a potential textile dyeeffluent bioremediation agent
ABSTRACT
Bacillus cereus incorporates the most important group of endospore-forming micro organism and can cause emetic and diarrheal food poisoning. A total of 42 B. cereus strains isolated from marketed raw chicken meat and human subjects swab samples were assessed by a triplex and multiplex PCR for the presence of enterotoxin genes. The detection rate of nheB, hblA, hblD, cytK, nheA,CER, hblC and entFM enterotoxin genes among all B. cereus strains was 83.33%, 80.95%, 69.04%, 21.42%, 47.61%, 0%, 61.90%, and 92.85% respectively. Enterotoxigenic profiles were determined in enterotoxin-producing strains showed 19 different patterns. The results offer essential information on toxin genes prevalence and toxigenic profiles of B. cereus from sources of origin. The present study was taken into consideration about extreme fitness danger for public health and insuring extra ability in difficulty to food safety amongst all B. cereus group members. Also, there may be need for extensive and continuous tracking of food products embracing both emetic toxin and enterotoxin genes.
ABSTRACT
El helado es un vehículo para la transmisión de patógenos como Bacillus cereus. Por lo cual, se determinó la frecuencia de cepas del grupo Bacillus cereus en helados, perfil enterotoxigénico, psicrofilia y producción de biopelícula. Un total de 230 muestras de seis marcas de helado de producción y distribución nacional fueron colectadas en México. El análisis microbiológico incluyó aislamiento en agar manitol yema de huevo. Las cepas se identificaron molecularmente a partir de la amplificación del gen de la topoisomerasa (gyrB) y el perfil enterotoxigénico por la amplificación de regiones conservadas de los operones nheABC y hblABD y del gen cytK. Además, se determinó la producción de biopelícula en vidrio y policloruro de vinilo. La frecuencia de contaminación por cepas del grupo B. cereus fue de 3,6%, se encontró una cepa positiva para nheABC y cinco para cytK, el 87,5% de las cepas generó biopelícula en vidrio y todas en policloruro de vinilo, dos cepas fueron psicrofilicas. En conclusión, en el helado distribuido en México, se encontró una baja contaminación por cepas del grupo B. cereus con alta producción de biopelícula; sin embargo, no se debe subestimar el potencial enterotoxigénico de estas cepas
Ice cream is a medium for microbial growth due to its nutritional value and neutral pH. Therefore, the frequency of strains of the Bacillus cereus group in ice cream was determined, the enterotoxigenic profile, psychrophilic strains and biofilm production. A total of 230 samples of six brands of ice cream produced and distributed nationwide were collected in Mexico. The microbiological analysis was a cold pre-enrichment and isolation of the microorganism in egg yolk agar. The strains were identified molecularly from the amplification of the topoisomerase gene (gyrB) and the enterotoxigenic profile by the amplification of conserved regions of the nheABC and hblABD operons and of the cytK gene. In addition, the production of biofilm in glass and polyvinyl chloride and psychophilia was determined. The frequency of contamination by strains of the B. cereus group was 3.6%, a positive strain was found for nheABC and five for cytK, 87.5% of the strains generated biofilm in glass and all in polyvinyl chloride, two strains were psychrophilic. In the ice cream distributed in Mexico, a low contamination by strain of the B. cereus group was found, however, the enterotoxigenic potential of the strains should not be underestimated
ABSTRACT
O objetivo deste trabalho foi avaliar a presença de B. cereus e G. stearothermophilus em 100 amostras de leite UAT (integral e desnatado). O isolamento dos esporos e das células vegetativas seguiu metodologias oficiais, com pequenas modificações. B. cereus foi isolada de 7% amostras de leite UHT, de 6 diferentes marcas. As contagens máximas de células vegetativas e esporos de B. cer eus foram de 3,54 Log UFC/mL e 3,93 Log esporos/mL, respectivamente. A presença dos genes codificadores de enterotoxina não hemolítica (NHE) foi observada em 33% dos isolados e da hemolisina (HBL ) em 100% dos isolados. O gene hblA foi encontrado em 91,6 % dos isolados, porém nenhum isolado apresentou os 3 genes do complexo HBL. G. stearothermophilus foi identificada em 22,8% (34/149) dos isolados de esporo altamente resistente ao calor (HRRS), representando 18% das amostras de leite UAT e as contagens de esporos variaram de < 1Log a 3,40 Log esporos/mL.