Efficient Isolation and Identification of Bacillus cereus Group

2012 ◽  
Vol 95 (2) ◽  
pp. 446-451 ◽  
Author(s):  
Sandra M Tallent ◽  
Kristin M Kotewicz ◽  
Errol A Strain ◽  
Reginald W Bennett
Keyword(s):  
Bacillus Cereus ◽  
Dairy Products ◽  
Egg Yolk ◽  
Bromothymol Blue ◽  
Foodborne Illnesses ◽  
Isolation And Identification ◽  
Bacillus Cereus Group ◽  
Gram Positive ◽  
Contaminated Food ◽  
Chromogenic Agar

Abstract Bacillus cereus is a group of ubiquitous facultative anaerobic sporeforming Gram-positive rods commonly found in soil. The spores frequently contaminate a variety of foods, including produce, meat, eggs, and dairy products. Foodborne illnesses associated with toxins produced by B. cereus can result in self-limiting diarrhea or vomiting. Plate enumeration methods recommended by recognized food authorities to detect the presence of B. cereus in potentially contaminated food products do not inhibit other Gram-positive competitive bacteria. This study evaluated the use of Bacara, a new chromogenic agar, as an efficient method to identify and enumerate B. cereus group from food matrixes, even in the presence of background flora. Inclusivity and exclusivity testing was performed using four different selective and differential media for B. cereus, including Mannitol Egg Yolk Polymyxin (MYP), Polymyxin Pyruvate Egg-Yolk Mannitol Bromothymol Blue Agar, Bacillus Chromogenic Media, Brilliance, and Bacara. MYP and Bacara were also used in plate enumeration studies to isolate B. cereus from artificially contaminated foods.

Improvement of Polymyxin–Egg Yolk–Mannitol–Bromothymol Blue Agar for the Enumeration and Isolation of Bacillus cereus in Various Foods

2017 ◽  
Vol 80 (3) ◽  
pp. 502-505
Author(s):  
Il-Byeong Kang ◽  
Jung-Whan Chon ◽  
Dong-Hyeon Kim ◽  
Dana Jeong ◽  
Hong-Seok Kim ◽  
...  
Keyword(s):  
Synergistic Effect ◽  
Bacillus Cereus ◽  
Egg Yolk ◽  
Bromothymol Blue ◽  
Food Samples ◽  
Red Pepper ◽  
Soybean Paste ◽  
Contaminated Food ◽  
Pepper Powder ◽  
Red Pepper Powder

ABSTRACT A modified polymyxin–egg yolk–mannitol–bromothymol blue agar (mPEMBA) was developed by supplementing polymyxin–egg yolk–mannitol–bromothymol blue agar (PEMBA) with trimethoprim to improve the selectivity for and recoverability of Bacillus cereus from naturally and artificially contaminated food samples. The number of B. cereus in mPEMBA was significantly higher than in PEMBA, indicating better recoverability (P < 0.05) in red pepper powder (PEMBA 0.80 ± 0.22 log CFU/g versus mPEMBA 1.95 ± 0.17 log CFU/g) and soybean paste (PEMBA 2.19 ± 0.18 log CFU/g versus mPEMBA 3.09 ± 0.13 log CFU/g). In addition, mPEMBA provided better visual differentiation of B. cereus colonies than PEMBA, which is attributable to the reduced number of competing microflora. We conclude that the addition of trimethoprim to PEMBA could generate a synergistic effect to improve selectivity for B. cereus.

Comparison of Media for Isolation of Bacillus cereus from Foods

1985 ◽  
Vol 48 (11) ◽  
pp. 969-970 ◽  
Author(s):  
MATS PETERZ ◽  
CHRISTER WIBERG ◽  
PER NORBERG
Keyword(s):  
Bacillus Cereus ◽  
Egg Yolk ◽  
Food Products ◽  
Bromothymol Blue ◽  
Blood Agar ◽  
The Media ◽  
Dry Food ◽  
Better Than ◽  
Quantitative Recovery

Three media for isolation of Bacillus cereus from foods were compared: mannitol-egg yolk-polymyxin (MYP) agar, polymyxin pyruvate-egg yolk-mannitol-bromothymol blue agar (PEMBA) and non-selective blood agar. Twenty-six of 45 samples of different reconstituted and incubated dry food products and 18 of 29 samples of milk and cream (incubated overnight) contained B. cereus. None of the media performed significantly better than the others as regards quantitative recovery or selectivity.

A Selective Chromogenic Agar That Distinguishes Bacillus anthracis from Bacillus cereus and Bacillus thuringiensis

2006 ◽  
Vol 69 (8) ◽  
pp. 2002-2006 ◽  
Author(s):  
MARGARET A. JUERGENSMEYER ◽  
BRUCE A. GINGRAS ◽  
LAWRENCE RESTAINO ◽  
ELON W. FRAMPTON
Keyword(s):  
Bacillus Thuringiensis ◽  
Bacillus Cereus ◽  
Bacillus Anthracis ◽  
Bacillus Species ◽  
Differential Rate ◽  
Chromogenic Substrate ◽  
Bacillus Cereus Group ◽  
Chromogenic Agar ◽  
Choline Phosphate ◽  
Group B

A selective and differential plating medium, R & F anthracis chromogenic agar (ACA), has been developed for isolating and identifying presumptive colonies of Bacillus anthracis. ACA contains the chromogenic substrate 5-bromo-4-chloro-3-indoxyl-choline phosphate that upon hydrolysis yields teal (blue green) colonies indicating the presence of phosphatidylcholinespecific phospholipase C (PC-PLC) activity. Among seven Bacillus species tested on ACA, only members of the Bacillus cereus group (B. anthracis, B. cereus, and B. thuringiensis) produced teal colonies (PC-PLC positive) having cream rings. Examination of colony morphology in 18 pure culture strains of B. anthracis (15 ATCC strains plus AMES-1-RIID, ANR-1, and AMED-RIID), with one exception, required 48 h at 35 to 37°C for significant color production, whereas only 24 h was required for B. cereus and B. thuringiensis. This differential rate of PC-PLC synthesis in B. anthracis (due to the truncated plcR gene and PlcR regulator in B. anthracis) allowed for the rapid differentiation on ACA of presumptive colonies of B. anthracis from B. cereus and B. thuringiensis in both pure and mixed cultures. Effective recovery of B. anthracis from a variety of matrices having both high (soil and sewage) and low microbial backgrounds (cloth, paper, and blood) spiked with B. anthracis ANR-1 spores suggests the probable utility of ACA plating for B. anthracis recovery in a diversity of applications.

scholarly journals Multi-locus sequence typing and virulence profile in Bacillus cereus sensu lato strains isolated from dairy products

2021 ◽  
Vol 9 (4) ◽  
Author(s):  
Angelica Bianco ◽  
Loredana Capozzi ◽  
Angela Miccolupo ◽  
Simona Iannetti ◽  
Maria Luisa Danzetta ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Bacillus Cereus ◽  
Dairy Products ◽  
Virulence Genes ◽  
Food Poisoning ◽  
Important Food ◽  
Food Contaminants ◽  
Bacillus Cereus Group ◽  
Mlst Analysis ◽  
Sequence Types

Members of Bacillus cereus group are important food contaminants and they are of relevant interest in food safety and public heath due to their ability to cause two distinct forms of food poisoning, emetic and diarrhoeal syndrome. In the present study, 90 strains of B. cereus isolated from dairy products, have been typed using Multilocus Sequence Typing (MLST) analysis and investigated for the occurrence of 10 enterotoxigenic genes (hblA, hblC, hblD, nheA, nheB, nheC, cytK, entFM, entS and bceT) and one emetogenic gene (ces), to determine their genetic diversity. A total of 58 sequence types were identified and among these 17 were signalled as new profiles. Among the virulence genes, the majority of our strains carried the entS (92%), entFM (86%), nhe (82%) and cytK (72%) genes. All remaining genes were identified in at least one strain with different prevalence, stressing the genetic diversity, how even the different grade of pathogenicity of B. cereus isolated from dairy products.

scholarly journals Bacteria from the Bacillus cereus group as contaminants in requeijão curd cheeses and especialidade láctea tipo requeijão

2018 ◽  
Vol 85 (0) ◽  
Author(s):  
Jamile de Oliveira Hachiya ◽  
Gabriel Augusto Marques Rossi ◽  
Higor Oliveira Silva ◽  
Rafael Akira Sato ◽  
Ana Maria Centola Vidal ◽  
...  
Keyword(s):  
Bacillus Cereus ◽  
Shelf Life ◽  
Dairy Products ◽  
Bacterial Group ◽  
Bacillus Cereus Group ◽  
Significant Difference ◽  
The Impact

ABSTRACT: This study aimed to evaluate the occurrence of Bacillus cereus group in requeijões and especialidades lácteas tipo requeijão (regular and light) and to verify if there is differences in relation to this occurrence among different categories of these products. A set of 14 (35%) lots was contaminated with this bacterial group from the 40 lots with low counts (maximum 3.1 × 10 CFU/g), and no significant difference regarding counts or presence/absence were observed among the categories of the products. It can be concluded that contamination by B. cereus group in these products is unable to consist in risk to consumers, regarding adequate refrigeration during selling. This study was the first one to report this bacteria group for these dairy products and highlights the needs of further investigations to evaluate the impact of its spoilage during shelf life.

scholarly journals Discrimination of Psychrotrophic and Mesophilic Strains of the Bacillus cereus Group by PCR Targeting of Major Cold Shock Protein Genes

1998 ◽  
Vol 64 (9) ◽  
pp. 3525-3529 ◽  
Author(s):  
Kevin P. Francis ◽  
Ralf Mayr ◽  
Felix von Stetten ◽  
Gordon S. A. B. Stewart ◽  
Siegfried Scherer
Keyword(s):  
Bacillus Cereus ◽  
Dairy Products ◽  
Cold Shock ◽  
Food Poisoning ◽  
Cold Shock Protein ◽  
Pcr Assay ◽  
Specific Primers ◽  
Bacillus Cereus Group ◽  
Cold Adapted ◽  
Pcr Targeting

ABSTRACT Detection of psychrotrophic strains (those able to grow at or below 7°C) of the Bacillus cereus group (Bacillus cereus, Bacillus thuringiensis, and Bacillus mycoides) in food products is at present extremely slow with conventional microbiology. This is due to an inability to discriminate these cold-adapted strains from their mesophilic counterparts (those able to grow only above 7°C) by means other than growth at low temperature, which takes 5 to 10 days for detection. Here we report the development of a single PCR assay that, using major cold shock protein-specific primers and appropriate annealing temperatures, is capable of both rapidly identifying bacteria of the B. cereus group and discriminating between psychrotrophic and mesophilic strains. It is intended that this development help to more accurately predict the shelf life of refrigerated pasteurized food and dairy products and to reduce the incidence of food poisoning by psychrotrophic strains of the B. cereus group.

Prevalence and Antimicrobial Resistance of Bacillus cereus in Milk and Dairy Products

2020 ◽  
Vol 21 (2) ◽  
pp. 11-18
Author(s):  
Rowayda Osama ◽  
Marwa Ahmed ◽  
Amir Abdulmawjood ◽  
Maha Al-Ashmawy
Keyword(s):  
High Temperature ◽  
Antimicrobial Resistance ◽  
Bacillus Cereus ◽  
Dairy Products ◽  
Milk Powder ◽  
Antibiotic Sensitivity ◽  
Isolation And Identification ◽  
Condensed Milk ◽  
Milk And Dairy Products ◽  
Ultra High Temperature

Objective: To investigate the prevalence of Bacillus cereus in milk and dairy products along with detection of its antibiotic sensitivity. Design: Descriptive study. Samples: One hundred and fifty samples of market milk, ultra high temperature milk packs (UHT), condensed milk, Milk powder, Damietta cheese, Kariesh cheese and Ras cheese. Procedures: Samples were examined for isolation and identification of Bacillus spp. via direct and indirect isolation, molecular examination and antimicrobial resistance. Further molecular examination was carried out in 46 isolates to detect hblA, hblC, hblD, nheA, nheB and nheC genes Results: The prevalence of B. cereus by direct isolation was 52%, 13.3 %, 10%, 8%,44%, 0 % and 16% in market milk, ultra high temperature milk packs (UHT) , condensed milk , Milk powder, Damietta cheese, Kariesh cheese and Ras cheese, respectively, whereas its prevalence by indirect isolation was 64%, 20%, 20%, 48%, 52%, 40% and 36% in market milk, ultra high temperature milk packs (UHT) , condensed milk , Milk powder, Damietta cheese, Kariesh cheese and Ras cheese, respectively. B. cereus isolates were 100% resistant to colistin (CT), ampicillin (AM) and amoxicillin (AML). However, 83.01% were resistant to ampicillin-sulbactum (SAM), 67.9% resistant to streptomycin (S), 45.2% resistant to spiramycin (SP), 35.8% resistant to lincomysin (MY), 22.6% resistant to tetracyclin (TE), and 5.6% resistant to erythromycin (E). A prevalence of 58.6% for hblA, hblC and hblD was recorded, while a prevalence of 86.9%, 93.4% and 89.1% for nheA, nheB and nheC was recorded. Conclusion and clinical relevance: This study provides data on prevalence, contamination level and antibiotic sensitivity of B. cereus in milk and its products, suggesting a potential risk to health and the dairy industry.

An improved selective and diagnostic medium for the isolation and enumeration of Bacillus cereus in foods

1980 ◽  
Vol 26 (7) ◽  
pp. 753-759 ◽  
Author(s):  
R. Holbrook ◽  
Judith M. Anderson
Keyword(s):  
Bacillus Cereus ◽  
Egg Yolk ◽  
Bromothymol Blue ◽  
Food Samples ◽  
Selective Medium ◽  
Confirmatory Test ◽  
Staining Procedure ◽  
Complete Agreement ◽  
Phenol Red ◽  
Biochemical Tests

The use and performance of an improved diagnostic and selective medium, PEMBA (polymyxin pyruvate egg yolk mannitol bromothymol blue agar), for the detection of Bacillus cereus in foods is described. The distinct colonial appearance of B. cereus on PEMBA permitted the recognition of both strains: those that do precipitate egg yolk and those that do not react with egg yolk. A staining procedure, used to demonstrate microscopically both the presence of lipid globules in vegetative cells and spore morphology of isolates, proved a rapid and reliable confirmatory test which gave complete agreement with a battery of biochemical tests used for this purpose. The quantitative recovery of B. cereus on PEMBA from 143 food samples was not significantly different from counts on KG (Kim and Goepfert), MYP (mannitol egg yolk phenol red), and McClung's media, and the selectivity of PEMBA was generally superior.

scholarly journals Use of Chromogenic Agar Media for Identification of Uropathogen

1970 ◽  
Vol 4 (1) ◽  
pp. 18-23
Author(s):  
Sohely Sharmin ◽  
Farhana Alamgir ◽  
Fahmida Begum ◽  
Md Qamrul Hassan Jaigirdar
Keyword(s):  
Biochemical Characterization ◽  
Agar Plate ◽  
Urine Samples ◽  
Isolation And Identification ◽  
Gram Positive ◽  
Single Organism ◽  
Color Differences ◽  
Enterococcus Spp ◽  
Chromogenic Agar ◽  
Agar Media

Chromogenic agar media are increasingly being used as versatile tools in early differentiation and identification of Gram positive and Gram negative isolates from clinical specimens. We have evaluated the chromogenic medium as it’s use reduces the burden of biochemical characterization and reduces the workload for identification of bacteria. This study included 400 consecutively collected midstream and/or catheter-catch urine samples obtained from patients attending the hospital out patient department (OPD) and also from patients admitted in BSMMU hospital. They were inoculated on blood agar, MacConkey agar, cystine lactose, electrolyte deficient media and chromogenic agar plate for isolation of uropathogen. Out of 400 urine samples tested, 154 (38.5%) yielded significant growth of single organism and 16 (4%) yielded mixed growth. No growth was observed in 230 (57.5%) cases. The chromogenic agar media allowed the growth and primary identification in 171 (92.5%) strains out of 186 strains. The predominant uropathogens were Escherichia coli, Klebsiella spp. Enterococcus spp. and Eneterobacter spp. (KES group). The different coloured colonies produced by the breakdown of the chromogenic substrate by the specific enzymes of the bacteria were very useful in the presumptive identification of these organisms even from polymicrobial cultures by the color differences of the colonies. The medium also supported growth and differentiation of Gram positive organisms like Staphylococcus and Enterococci. Chromogenic agar media can be used as primary culture medium for isolation and identification of predominant uropathogens like E.coli, KES group and Enterococci. It is an easy to use primary screening medium that considerably reduces the daily workload and thus minimizes or limits the use of identification tests. Key words: Chromogenic agar medium, KES, CLED media, UTI DOI: http://dx.doi.org/10.3329/bjmm.v4i1.8464 BJMM 2011; 4(1): 18-23

Sign in / Sign up

Export Citation Format

Share Document