Biofilm Production by Enterotoxigenic Strains of Bacillus cereus in Different Materials and under Different Environmental Conditions

Foodborne illnesses, such as infections or food poisoning, can be caused by bacterial biofilms present in food matrices or machinery. The production of biofilms by several strains of Bacillus cereus on different materials under different culture conditions was determined, as well as the relationship of biofilms with motility, in addition to the enterotoxigenic profile and candidate genes that participate in the production of biofilms. Biofilm production of B. cereus strains was determined on five materials: glass, polystyrene, polyethylene, polyvinylchloride (PVC), PVC/glass; in three culture media: Phenol red broth, tryptic soy broth, and brain heart infusion broth; in two different temperatures (37 °C and 25 °C), and in two different oxygen conditions (oxygen and CO2 tension). Furthermore, the strains were molecularly characterized by end-point polymerase chain reaction. Motility was determined on semi-solid agar. The B. cereus strains in this study were mainly characterized as enterotoxigenic strains; statistically significant differences were found in the PVC material and biofilm production. Motility was positively associated with the production of biofilm in glass/PVC. The sipW and tasA genes were found in two strains. The results of this study are important in the food industry because the strains carry at least one enterotoxin gene and produce biofilms on different materials

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Comparative Analysis of L-Carnitine Production by Y. Lipolytica in Different Conditions in Biofuel Waste and Fat-Acid Free Medium for Commercial Purposes

10.21203/rs.3.rs-423648/v1 ◽

2021 ◽

Author(s):

Monika Jach ◽

Konrad Kubiński ◽

Ewa Sajnaga ◽

Marek Juda ◽

Anna Malm

Keyword(s):

Yarrowia Lipolytica ◽

Culture Media ◽

Dry Weight ◽

Culture Conditions ◽

Industrial Wastes ◽

Yeast Biomass ◽

Wet Biomass ◽

Different Temperatures ◽

Carnitine Concentration ◽

Biofuel Waste

Abstract Background Yarrowia lipolytica is an oleaginous yeast with the ability to grow in a variety of hydrophilic and hydrophobic substrates, including industrial wastes, in which it produces and accumulates various nutrients. Methods The aim of the present study was to examine the presence of free L-carnitine in the biomasses of two Yarrowia lipolytica strains (ATCC 9793 and A-101) growing in YPD medium and biofuel waste. The cultivations of Y. lipolytica were performed in aerobic conditions at different temperatures (20–30°C) and pH values (4.0–7.0) of the media with and without the addition of precursors for L-carnitine production, such us iron, trimethyllysine, and L-ascorbic acid in a laboratory scale or chromium chloride (III) in a pilot plant scale. Results Both tested Y. lipolytica strains grown in fatty acid-poor YPD medium at 20°C and pH 6.0 contained endogenous free L-carnitine in their biomass with a maximum of 22.85 mg/100 g of wet biomass. The addition of L-carnitine precursors to the YPD medium exerted a significant effect on L-carnitine concentration in the yeast biomass, increasing it up to 250%. In turn, the biomass of both tested Y. lipolytica strains cultivated in the biofuel waste, irrespective of the culture conditions, contained below 1 mg of L-carnitine/100 g of wet biomass. However, the supplementation of the culture media with the L-carnitine precursors significantly increased the yield of the yeast biomass by 20–30% in the biofuel waste cultures. Moreover, the addition of chromium(III) chloride into the biofuel waste caused an increase in the free L-carnitine concentration in the yeast biomass up to 2.24 mg/100 g of dry weight. Conclusion Biomass of Y. lipolytica grown in the free fat medium contained free L-carnitine, in contrast to the biomass grown in the fat-rich biofuel waste. The very low amounts of L-carnitine in the biomass of Y. lipolytica grown in the crude biofuel waste suggest that the yeast is able to utilize almost the entire pool of free L-carnitine for growth and nutritional biomass production. However, the addition of chromium to the biofuel waste contributed to an increase in L-carnitine concentration in Y. lipolytica biomass.

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LIGHT SCATTERING SENSOR FOR RAPID DETECTION OF BACILLUS CEREUS IN CHICKEN MEATS

Mansoura Veterinary Medical Journal ◽

10.35943//mvmj.2018.19.1212 ◽

2018 ◽

pp. 57-68

Author(s):

Maha Abdalhaseib ◽

Arun Bhunia

Keyword(s):

Light Scattering ◽

Bacillus Cereus ◽

Rapid Detection ◽

Agar Plate ◽

Food Poisoning ◽

Opportunistic Pathogen ◽

Phenol Red ◽

High Throughput Analysis ◽

Software Analysis ◽

Detection And Identification

Bacillus cereus is an opportunistic pathogen causing food poisoning, manifested by diarrhea or emetic illnesses. BARDOT (BActerial Rapid Detection using Optical scattering Technology) directly capturing phenotypic CHARacteristics of colonies following standard agar plating, providing non-destructive, high-throughput analysis and real-time detection of colonies on agar plate without any labeling reagents or probes. This study implement light scattering sensor in detection and identification of B. cereus on genus level in mixed cultures and in artificially inoculated chicken samples using PRM (phenol red mannitol) agar. Software analysis and PCR confirmation showed that BARDOT successfully detect 100% of B. cereus in mixed culture and >90% of artificially inoculated chicken samples. This results demonstrates that BARDOT could be used as a screening tool to identify Bacillus cereus from other pathogens and background flora on PRM agar

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Evaluation of growth and cereulide production by Bacillus cereus isolated from cooked rice

International Journal of Food Studies ◽

10.7455/9.1.2020.a1 ◽

2020 ◽

Vol 9 (1) ◽

Author(s):

Damilola O. Seyi-Amole ◽

Abiodun A. Onilude ◽

Dasari S. Rani ◽

Prakash M. Halami

Keyword(s):

Bacillus Cereus ◽

Incubation Period ◽

Food Poisoning ◽

Optimum Growth ◽

Ph Values ◽

Cooked Rice ◽

Incubation Periods ◽

Different Temperatures ◽

Static Conditions ◽

Incubation Temperatures

Conditions influencing Bacillus cereus growth and cereulide production, such as temperature and pH, were evaluated at varying incubation periods. The growth and cereulide production at different temperatures and pH values ranging from 10 to 40 ºC and 5.0 to 8.5, respectively showed that the temperature from 20 to 30 ºC and at pH from 6.0 to 7.0 gave the optimum growth and cereulide production by B. cereus SA105. pH below 6.0 resulted in reduced growth and cereulide production. Cereulide production increased along with the incubation period, and maximum cereulide titre (ng/mL) of 1219.1±8.90 was obtained after 6 days of incubation at 30 ºC and pH 6.5 under static conditions. There was no quantifiable toxin at incubation temperatures of 10 and 40 ºC by B. cereus SA105. This work further reveals that B. cereus growth and cereulide production was significantly affected by temperature and pH in relation to the incubation period. Furthermore, the findings of this study will serve as a means for reducing the diversity of emetic toxin-producing B. cereus population in food and food products, thus preventing food poisoning.

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Production of Diarrheal Enterotoxins and Other Potential Virulence Factors by Veterinary Isolates of Bacillus Species Associated with Nongastrointestinal Infections

Applied and Environmental Microbiology ◽

10.1128/aem.69.4.2372-2376.2003 ◽

2003 ◽

Vol 69 (4) ◽

pp. 2372-2376 ◽

Cited By ~ 57

Author(s):

Neil J. Rowan ◽

George Caldow ◽

Curtis G. Gemmell ◽

Iain S. Hunter

Keyword(s):

Bacillus Cereus ◽

Virulence Factors ◽

Dna Sequences ◽

Food Poisoning ◽

Brain Heart Infusion ◽

Bacillus Species ◽

Genes Encoding ◽

Test Cell Line ◽

Etiological Agents ◽

Hemolysin Bl

ABSTRACT With the exceptions of Bacillus cereus and Bacillus anthracis, Bacillus species are generally perceived to be inconsequential. However, the relevance of other Bacillus species as food poisoning organisms and etiological agents in nongastrointestinal infections is being increasingly recognized. Eleven Bacillus species isolated from veterinary samples associated with severe nongastrointestinal infections were assessed for the presence and expression of diarrheagenic enterotoxins and other potential virulence factors. PCR studies revealed the presence of DNA sequences encoding hemolysin BL (HBL) enterotoxin complex and B. cereus enterotoxin T (BceT) in five B. cereus strains and in Bacillus coagulans NB11. Enterotoxin HBL was also harbored by Bacillus polymyxa NB6. After 18 h of growth in brain heart infusion broth, all seven Bacillus isolates carrying genes encoding enterotoxin HBL produced this toxin. Cell-free supernatant fluids from all 11 Bacillus isolates demonstrated cytotoxicity toward human HEp-2 cells; only one Bacillus licheniformis strain adhered to this test cell line, and none of the Bacillus isolates were invasive. This study constitutes the first demonstration that Bacillus spp. associated with serious nongastrointestinal infections in animals may harbor and express diarrheagenic enterotoxins traditionally linked to toxigenic B. cereus.

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Thermal Injury and Recovery of Bacillus cereus

Journal of Food Protection ◽

10.4315/0362-028x-41.7.533 ◽

1978 ◽

Vol 41 (7) ◽

pp. 533-537 ◽

Cited By ~ 6

Author(s):

HARRIET RAPPAPORT ◽

J. M. GOEPFERT

Keyword(s):

Bacillus Cereus ◽

Phosphate Buffer ◽

Thermal Injury ◽

Potassium Phosphate ◽

Brain Heart Infusion ◽

Plate Count ◽

Protein Synthesis Inhibitor ◽

Phenol Red ◽

Potassium Phosphate Buffer ◽

Synthesis Inhibitor

A system to measure thermal injury to vegetative cells of Bacillus cereus B4ac was developed. After heating in 0.1 M potassium phosphate buffer, pH 6.0 for 5 min at 47 C, cells became both pH-and NaCl-sensitive. The cell population showed decreased viability at pH values less than 6.3 or greater than 7.3, and at concentrations of 2% NaCl or greater in plating media. Cells did not become sensitive to polymyxin B sulfate and/or phenol red at concentrations in which these substances are present in media routinely used to enumerate B. cereus in foods. Injury was normally detected as differential plating ability on Plate Count Agar (PCA) vs. PCA plus 2.5% NaCl. Injured cells could partially recover in 0.1% peptone, Brain Heart Infusion broth (pH 7.3), a mixture of 20 amino acids (10 or 50 μg/ml each), 1% glucose, and 0.1% peptone plus a protein synthesis inhibitor (chloramphenicol, 2.5 μg/ml) or 0.1% peptone plus a DNA replication inhibitor (nalidixic acid, 5 μg/ml). Cells recovered equally well at 20, 32 and 37 C. Recovery did not occur in 0.1% peptone plus an RNA synthesis inhibitor (rifampicin, 7.5 ng/ml) or in 0.1 M potassium phosphate buffer, pH 6.0 or 7.0.

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Comparative Analysis of L-Carnitine Production by Y. Lipolytica in Different Culture Conditions in Biofuel Waste and Fatty-Poor Medium for Commercial Purposes

10.21203/rs.3.rs-684424/v1 ◽

2021 ◽

Author(s):

Monika Elżbieta Jach ◽

Konrad Kubiński ◽

Marek Juda ◽

Ewa Sajnaga ◽

Tomasz Baj ◽

...

Keyword(s):

Yarrowia Lipolytica ◽

Culture Media ◽

Culture Conditions ◽

Industrial Wastes ◽

Yeast Biomass ◽

Wet Biomass ◽

Other Substances ◽

Different Temperatures ◽

Carnitine Concentration ◽

Biofuel Waste

Abstract BackgroundYarrowia lipolytica is oleaginous yeast with the ability to grow in a variety of hydrophilic and hydrophobic substrates, including industrial wastes, in which it produces and accumulates various nutrients.MethodsThe aim of the present study was to examine the presence of free L-carnitine in the biomasses of two Yarrowia lipolytica strains (A-101 and ATCC 9793) growing in biofuel waste and YPD medium. The cultivations of Y. lipolytica were performed in aerobic conditions at different temperatures (20-30°C) and pH values (4.0-7.0) of the media with and without the addition of precursors for L-carnitine production (trimethyllysine, iron, and L-ascorbic acid) in a laboratory scale or other substances (chromium, selenite, or zinc) in a pilot plant scale.ResultsBoth tested Y. lipolytica strains grown in fatty acid-poor YPD medium at 20°C and pH 6.0 contained endogenous free L-carnitine in their biomass with a maximum of 22.85 mg/100 g of wet biomass. The addition of L-carnitine precursors to the YPD medium exerted a significant effect on L-carnitine concentration in the yeast biomass, increasing it up to 250%. In turn, the biomass of both tested Y. lipolytica strains cultivated in the biofuel waste, irrespective of the culture conditions, contained below 1 mg of L-carnitine/100 g of wet biomass. However, the supplementation of the culture media with the L-carnitine precursors significantly increased the yield of the yeast biomass by 20-30% in the non-fermentable biofuel waste cultures. Moreover, the addition of chromium (III) chloride into the biofuel waste caused an increase in the free L-carnitine concentration in the yeast biomass up to 2.24 mg/100 g of dry weight.ConclusionBiomass of Y. lipolytica grown in the fatty-poor medium contained free L-carnitine, in contrast to the biomass grown in the fat-rich biofuel waste. The very low amounts of L-carnitine in the biomass of Y. lipolytica grown in the crude biofuel waste suggest that the yeast is able to utilize almost the entire pool of free L-carnitine for growth and nutritional biomass production. However, the addition of chromium to the biofuel waste contributed to an increase in L-carnitine concentration in Y. lipolytica biomass.

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Evaluation of growth and cereulide production by Bacillus cereus isolated from cooked rice

International Journal of Food Studies ◽

10.7455/ijfs/9.1.2020.a1 ◽

2020 ◽

Vol 9 (1) ◽

Author(s):

Damilola O. Seyi-Amole ◽

Abiodun A. Onilude ◽

Dasari S. Rani ◽

Prakash M. Halami

Keyword(s):

Bacillus Cereus ◽

Incubation Period ◽

Food Poisoning ◽

Optimum Growth ◽

Ph Values ◽

Cooked Rice ◽

Incubation Periods ◽

Different Temperatures ◽

Static Conditions ◽

Incubation Temperatures

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Effect of Culture Conditions on Production of Cytotoxic Enterotoxin of Aeromonas sobria

Bangladesh Journal of Microbiology ◽

10.3329/bjm.v23i2.888 ◽

1970 ◽

Vol 23 (2) ◽

pp. 171-173 ◽

Cited By ~ 1

Author(s):

Zeaur Rahim ◽

Sirajul Islam Khan ◽

Qazi Shafi Ahmed ◽

Khan M Nasirul Islam

Keyword(s):

Sodium Chloride ◽

Vero Cell ◽

Yeast Extract ◽

Culture Media ◽

Brain Heart Infusion ◽

Culture Conditions ◽

Casamino Acid ◽

Aeromonas Sobria ◽

Vero Cell Line ◽

Positive Isolate

Cytotoxic enterotoxin (Act) production of a cytotoxic enterotoxin (act) gene-positive isolate of Aeromonas sobria was studied in different bacteriological culture media, such as brain heart infusion (BHIB), trypticase soy broth with yeast extract (TSB), casamino acid yeast extract and Richardson's medium. Cytotoxin production was evaluated in Vero cell-line. Of the various media tested, higher titre of Act was produced in BHIB. Production of Act was enhanced when calcium (1 mM), Mg (10 mM), iron (200 ìM) and sodium chloride (0.5%) was supplemented in BHIB. Keywords: Aeromonas sobria, cytotoxic enterotoxin (Act), Vero cell-assay DOI: http://dx.doi.org/10.3329/bjm.v23i2.888 Bangladesh J Microbiol, Volume 23, Number 2, December 2006, pp 171-173

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KEJADIAN LUAR BIASA KERACUNAN “CUMI-CUMIAN” DI SEKOLAH DASAR NEGERI 1 TRASAN BANDONGAN KABUPATEN MAGELANG

Media Ilmu Kesehatan ◽

10.30989/mik.v7i2.280 ◽

2018 ◽

Vol 7 (2) ◽

pp. 131-136

Author(s):

Nasir Ahmad

Keyword(s):

Abdominal Pain ◽

Bacillus Cereus ◽

Rhodamine B ◽

Attack Rate ◽

Food Poisoning ◽

Health Department ◽

Analysis Data ◽

Food Samples ◽

Bivariate Analysis ◽

School Committee

Background: On May 4th, 2016, at 12:30 district surveillance officer of Magelang Health Department received reports from Public Health Center of Bandongan about 21 students of SDN 1 Trasan who suffered from the same food-poisoning symptoms. Objective: Investigation was carried out to identify the source, how it spread and how to control it. Methods: This study used descriptive analytic and mapping the cases distribution location. The case was people experiencing symptoms of dizziness or abdominal pain or nausea or vomiting. Data analysis was done by using bivariate analysis. Data collection were done through interviews, observations and laboratory tests on the food samples. Results: The case was 50 students (from 1-6 grade students). The perceived symptoms were dizziness (77%), nausea (42%), abdominal pain (40%) and vomiting (8%). Attack rate found ranged from 14.3% to 60% with the highest Attack rate found on class three (60%). The incubation period of 15-240 minutes (mean 72.3 minutes). Calamari like positive Bacillus cereus and Rhodamine-B 10 mg/kg. Conclusion: The outbreak of food poisoning because calamari like contaminated Bacillus cereus. We suggested the school committee to provide the socialization of harmful food for the students. The teachers should restrict the permission for the food vendor to sell at school. Keywords: Bacillus cereus, , Food Poisoning, Outbreak, Rhodamine B, School Food

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Effect of temperature, CO2 and O2 on motility and mobility of Anisakidae larvae

Scientific Reports ◽

10.1038/s41598-021-83505-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aiyan Guan ◽

Inge Van Damme ◽

Frank Devlieghere ◽

Sarah Gabriël

Keyword(s):

Enzymatic Digestion ◽

Infected Fish ◽

Effect Of Temperature ◽

Video Recordings ◽

Different Temperatures ◽

Semi Solid ◽

Zoonotic Parasites ◽

The Impact ◽

Phosphate Buffered Saline

AbstractAnisakidae, marine nematodes, are underrecognized fish-borne zoonotic parasites. Studies on factors that could trigger parasites to actively migrate out of the fish are very limited. The objective of this study was to assess the impact of different environmental conditions (temperature, CO2 and O2) on larval motility (in situ movement) and mobility (migration) in vitro. Larvae were collected by candling or enzymatic digestion from infected fish, identified morphologically and confirmed molecularly. Individual larvae were transferred to a semi-solid Phosphate Buffered Saline agar, and subjected to different temperatures (6 ℃, 12 ℃, 22 ℃, 37 ℃) at air conditions. Moreover, different combinations of CO2 and O2 with N2 as filler were tested, at both 6 °C and 12 °C. Video recordings of larvae were translated into scores for larval motility and mobility. Results showed that temperature had significant influence on larval movements, with the highest motility and mobility observed at 22 ℃ for Anisakis spp. larvae and 37 ℃ for Pseudoterranova spp. larvae. During the first 10 min, the median migration of Anisakis spp. larvae was 10 cm at 22 ℃, and the median migration of Pseudoterranova spp. larvae was 3 cm at 37 ℃. Larval mobility was not significantly different under the different CO2 or O2 conditions at 6 °C and 12 ℃. It was concluded that temperature significantly facilitated larval movement with the optimum temperature being different for Anisakis spp. and Pseudoterranova spp., while CO2 and O2 did not on the short term. This should be further validated in parasite-infected/spiked fish fillets.

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