Biochemistry test of bacteria-1 (urease test, carbohydrate fermentation, catalase test, oxidase test)

2022 ◽  
pp. 67-76
Author(s):  
Cangliang Shen ◽  
Yifan Zhang
2017 ◽  
Vol 11 (1) ◽  
pp. 126-131 ◽  
Author(s):  
Ali M. Bazzi ◽  
Jaffar A. Al-Tawfiq ◽  
Ali A. Rabaan

Introduction:Acinetobacter baumanniiandBrucellaspecies are Gram-negative organisms that are vulnerable to misinterpretation as Gram-positive or Gram-variable in blood cultures.Objective:We assess the random errors in gram stain interpretation to reduce the likelihood of such errors and therefore patient harm.Methodology:Aerobic and anaerobic blood cultures from two patients in an acute care facility in Saudi Arabia were subjected to preliminary Gram-staining. In case 1, VITEK-2 Anaerobe Identification, repeat Gram staining from a blood agar plate, Remel BactiDrop™ Oxidase test, Urea Agar urease test and real-time PCR were used to confirm presence ofBrucellaand absence ofCoryneformspecies. In case 2, repeat Gram- staining from the plate and the vials, VITEK-2 Gram-Negative Identification, real-time PCR and subculture on to Columbia agar, blood agar, and MacConkey agar were carried out to identifyA. baumannii.Results:In case 1, initially pleomorphic Gram-positive bacteria were identified.Coryneformspecies were suspected. Tiny growth was observed after 24 h on blood agar plates, and good growth by 48 h. Presence ofBrucellaspecies was ultimately confirmed. In case 2, preliminary Gram-stain results suggested giant Gram-positive oval cocci. Further testing over 18-24 h identifiedA. baumannii.Conclusions:Oxidase test from the plate and urease test from the culture vial is recommended after apparent identification of pleomorphic Gram-positive bacilli from blood culture, once tiny growth is observed, to distinguishBrucellafromCorynebacteriumspecies. If giant Gram-positive oval cocci are indicated by preliminary Gram-staining, it is recommended that the Gram stain be repeated from the plate after 4-6 h, or culture should be tested in Triple Sugar Iron (TSI) medium and the Gram stain repeated after 2-4 h incubation.


2021 ◽  
Vol 9 (1) ◽  
pp. 11-16
Author(s):  
Nor Azyan K.M. Khaidi ◽  
Siti M. Anua ◽  
Nurzafirah Mazlan ◽  
Safaa N. Saud

Aim: The aim of this study is to determine the presence of microbial air contaminants in the operating theatre at a teaching hospital. Objective: Airborne microbial level in operation theatre is one of the significant risks in hospital as it can increase the surgical site infection and nosocomial infections. Background: Duo SAS Super 360 Air Sampler was used to collect the airborne samples in triplicate each for nutrient and MacConkey agar at eight operation rooms and two corridors for morning and evening sessions. Sampling was conducted for three months and repeated every two months. Microbiological culture, gram staining and biochemical tests such as catalase test, oxidase test, coagulase test, Triple Sugar Iron Agar test, urease test, citrate test, Sulfide, Indole, Motility test, Methyl Red Voges-Proskauer test, disc diffusion test, and Albert’s stain were performed on the pure isolated culture. Methods: Sampling was conducted for three months and repeated every two months. Microbiological culture, gram staining and biochemical tests such as catalase test, oxidase test, coagulase test, Triple Sugar Iron Agar test, urease test, citrate test, Sulfide, Indole, Motility test, Methyl Red Voges- Proskauer test, disc diffusion test, and Albert’s stain were performed on the pure isolated culture. Bacteria that were present in the operation rooms were Bacillus spp., Micrococcus spp. and Staphylococcus spp. while Pseudomonas aeruginosa and Acinetobacter baumannii were absent. The bacteria identified in the operation theater may also cause surgical site infections and nosocomial infections to the patients, although the microbial contamination in the air of the operation theatre is low. Results: The bacteria identified in the operation theater may also cause surgical site infections and nosocomial infections to the patients, although the microbial contamination in the air of the operation theatre is low. Conclusion: Strengthening surveillance on the hygienic condition of the operation theatre and routine sampling is strongly recommended to control all possible sources and types of infection.


Author(s):  
Teresa D. Rebaza-Cardenas ◽  
Kenneth Silva-Cajaleón ◽  
Carlos Sabater ◽  
Susana Delgado ◽  
Nilda D. Montes-Villanueva ◽  
...  

AbstractIn this work, two Peruvian beverages “Masato de Yuca,” typical of the Amazonian communities made from cassava (Manihot esculenta), and “Chicha de Siete Semillas,” made from different cereal, pseudo-cereal, and legume flours, were explored for the isolation of lactic acid bacteria after obtaining the permission of local authorities following Nagoya protocol. From an initial number of 33 isolates, 16 strains with different RAPD- and REP-PCR genetic profiles were obtained. In Chicha, all strains were Lactiplantibacillus plantarum (formerly Lactobacillus plantarum), whereas in Masato, in addition to this species, Limosilactobacillus fermentum (formerly Lactobacillus fermentum), Pediococcus acidilactici, and Weissella confusa were also identified. Correlation analysis carried out with their carbohydrate fermentation patterns and enzymatic profiles allowed a clustering of the lactobacilli separated from the other genera. Finally, the 16 strains were submitted to a static in vitro digestion (INFOGEST model) that simulated the gastrointestinal transit. Besides, their ability to adhere to the human epithelial intestinal cell line HT29 was also determined. Following both procedures, the best probiotic candidate was Lac. plantarum Ch13, a robust strain able to better face the challenging conditions of the gastrointestinal tract and showing higher adhesion ability to the intestinal epithelium in comparison with the commercial probiotic strain 299v. In order to characterize its benefit for human health, this Ch13 strain will be deeply studied in further works.


Author(s):  
Marietta Zita Poles ◽  
László Juhász ◽  
Mihály Boros

AbstractMammalian methanogenesis is regarded as an indicator of carbohydrate fermentation by anaerobic gastrointestinal flora. Once generated by microbes or released by a non-bacterial process, methane is generally considered to be biologically inactive. However, recent studies have provided evidence for methane bioactivity in various in vivo settings. The administration of methane either in gas form or solutions has been shown to have anti-inflammatory and neuroprotective effects in an array of experimental conditions, such as ischemia/reperfusion, endotoxemia and sepsis. It has also been demonstrated that exogenous methane influences the key regulatory mechanisms and cellular signalling pathways involved in oxidative and nitrosative stress responses. This review offers an insight into the latest findings on the multi-faceted organ protective activity of exogenous methane treatments with special emphasis on its versatile effects demonstrated in sepsis models.


2010 ◽  
Vol 5 (3) ◽  
pp. 257-258 ◽  
Author(s):  
Angelo Zullo ◽  
Cesare Hassan ◽  
Silvia Trapani ◽  
Gianfranco Tammaro

Science ◽  
1945 ◽  
Vol 101 (2627) ◽  
pp. 470-470 ◽  
Author(s):  
T. G. ANDERSON
Keyword(s):  

2014 ◽  
Vol 51 (3) ◽  
pp. 180-185 ◽  
Author(s):  
Juliana Ghisleni de OLIVEIRA ◽  
Cristina Helena Targa FERREIRA ◽  
Anna Carolina Saraiva CAMERIN ◽  
Cláudia Augustin ROTA ◽  
Luíse MEURER ◽  
...  

Context Helicobacter pylori (H. pylori) has a worldwide distribution, but the prevalence of infection, virulence factors, and clinical presentation vary widely according to the studied population. In Brazil, a continental country composed of several ethnicities and cultural habits, the behavior of infection also appears to vary, as many other studies have shown. Objectives Describe the prevalence of infection with cagA-positive H. pylori strains in a group of children and adolescents who underwent esophagogastroduodenoscopy in Porto Alegre, Rio Grande do Sul. Methods Fifty-four gastric biopsy specimens of children and adolescents with H. pylori infection demonstrated by histology, urease test and molecular analysis were tested for the presence of cagA positive H. pylori strains by the polymerase chain reaction method. Results he prevalence of cagA-positive H. pylori was 29.6% (95% confidence interval, 18 to 43.6%). There were no statistically significant differences in clinical or demographic characteristics or in the endoscopic and histological features of patients infected with cagA-positive strains as compared with those infected by cagA-negative strains. Conclusions he study showed a low prevalence of infection with cagA-positive H. pylori strains among children and adolescents who underwent EGD in southern Brazil, in comparison to studies conducted with children from other regions of Brazil. There was no association between the presence of cagA-positive strains and more severe clinical presentations in the studied sample.


Sign in / Sign up

Export Citation Format

Share Document