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Rice panicle blight (RPB) caused by various Fusarium spp. is an emerging disease in the major rice-growing regions of China. Epidemics of this disease cause significant yield loss and reduce grain quality by contaminating panicles with different Fusarium toxins. However, there is currently no registered fungicide for the control of RPB in China. The 14α-demethylation inhibitor (DMI) fungicide metconazole has been shown to be effective against several Fusarium spp. that cause wheat head blight, wheat crown rot and maize ear rot. In this study, we investigated the specific activity of metconazole against six Fusarium spp. that cause RPB. Metconazole significantly inhibited mycelial growth, conidium formation, germination, germ tube elongation and major toxin production in Fusarium strains collected from major rice-growing regions in China, as well as disrupting cell membrane function by inhibiting ergosterol biosynthesis. Greenhouse experiments indicated a significant reduction in blight occurrence and toxin accumulation in rice panicles treated with metconazole. Overall, our study demonstrated the potential of metconazole for managing RPB and toxin contamination, as well as providing insight into its bioactivities and modes of action of metconazole against distinct Fusarium spp.

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OBJECTIVES: From September 2022 an increase in Corynebacterium diphtheriae (C. diphtheriae) infections was reported in Europe. Our study focuses on 31 adolescent and young adult refugees with cutaneous C. diphtheriae infections detected in Germany. We examined treatment regimens and outcomes to provide targeted insights into the management of this infection. METHODS: We distributed a standardized survey, focused on children and adolescents presenting to paediatric clinics through the German Paediatric Infectious Diseases Society (DGPI) and additional professional contacts in Germany. Data were extracted from routine medical documentation and reported anonymously. RESULTS: A total of 31 individuals with cutaneous C. diphtheriae infection were reported by 9 centres. Two of these showed diphtheria toxin (DT) related systemic symptoms and four exhibited systemic inflammation requiring complex management. The remaining 25 cases, with exclusively cutaneous manifestations, were afebrile. Treatment with topical antiseptics and systemic antibiotics, mainly aminopenicillin/beta-lactamase inhibitors (BLI) (35%) or clindamycin (25%), achieved eradication in all but two cases treated with aminopenicillin/BLI. Treatment duration varied between 5 and 17 days. CONCLUSIONS: In refugees presenting with chronic skin wounds, C. diphtheriae should be included into the differential diagnosis. Fever seems to be a valuable marker to differentiate severe cases with potentially DT-mediated sequelae from exclusively cutaneous diphtheria (CD). For afebrile CD, topical antiseptics and oral antibiotic therapy with clindamycin for 7 days, followed by clinical surveillance appears to be a safe treatment regimen. Patients with CD who present with fever or pharyngitis should be thoroughly investigated including blood and pharyngeal swab cultures.

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Fungi are rich sources of secondary metabolites of agrochemical, pharmaceutical, and food importance, such as mycotoxins, antibiotics, and antitumor agents. Secondary metabolites play vital roles in fungal pathogenesis, growth and development, oxidative status modulation, and adaptation/resistance to various environmental stresses. LaeA contains an S-adenosylmethionine binding site and displays methyltransferase activity. The members of velvet proteins include VeA, VelB, VelC, VelD and VosA for each member with a velvet domain. LaeA and velvet proteins can form multimeric complexes such as VosA-VelB and VelB-VeA-LaeA. They belong to global regulators and are mainly impacted by light. One of their most important functions is to regulate gene expressions that are responsible for secondary metabolite biosynthesis. The aim of this mini-review is to represent the newest cognition of the biosynthetic regulation of mycotoxins and other fungal secondary metabolites by LaeA and velvet proteins. In most cases, LaeA and velvet proteins positively regulate production of fungal secondary metabolites. The regulated fungal species mainly belong to the toxigenic fungi from the genera of Alternaria, Aspergillus, Botrytis, Fusarium, Magnaporthe, Monascus, and Penicillium for the production of mycotoxins. We can control secondary metabolite production to inhibit the production of harmful mycotoxins while promoting the production of useful metabolites by global regulation of LaeA and velvet proteins in fungi. Furthermore, the regulation by LaeA and velvet proteins should be a practical strategy in activating silent biosynthetic gene clusters (BGCs) in fungi to obtain previously undiscovered metabolites.

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Ochratoxin A (OTA) is a mycotoxin mainly produced by Aspergillus section Circumdati and section Nigri across the coffee chain. OTA is nephrotoxic and is a threat to human health. This review summarizes current knowledge on how to reduce OTA concentration in coffee from farm to cup. After a brief introduction to the OTA occurrence in coffee, current good management practices are introduced. The core of this review focuses on biocontrol and microbial decontamination by lactic acid bacteria, yeasts and fungi, and their associated enzymes currently reported in the literature. Special attention is given to publications closest to in vivo applications of biocontrol agents and microbial OTA adsorption or degradation agents. Finally, this review provides an opinion on which future techniques to promote within the coffee supply chain.

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Although diphtheria is a vaccine-preventable disease, numerous cases are still reported around the world, as well as outbreaks in countries, including European ones. Species of the Corynebacterium diphtheriae complex are potentially toxigenic and, therefore, must be considered given the possible consequences, such as the circulation of clones and transmission of antimicrobial resistance and virulence genes. Recently, Corynebacterium rouxii was characterized and included among the valid species of the complex. Therefore, two cases of C. rouxii infection arising from infections in domestic animals are presented here. We provide molecular characterization, phylogenetic analyses, genome sequencing, and CRISPR-Cas analyses to contribute to a better understanding of the molecular bases, pathogenesis, and epidemiological monitoring of this species, which is still little studied. We confirmed its taxonomic position with genome sequencing and in silico analysis and identified the ST-918 for both strains. The clinical isolates were sensitive resistance to benzylpenicillin and rifampin. Antimicrobial resistance genes, including tetB, rpoB2, and rbpA genes, were predicted. The bla and ampC genes were not found. Several virulence factors were also detected, including adhesion, iron uptake systems, gene regulation (dtxR), and post-translational modification (MdbA). Finally, one prophage and the Type I-E CRISPR-Cas system were identified.

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Degnala is one of the primary mycotoxicoses affecting buffaloes, with Fusarium spp. as the main causative agent. This disease is strongly associated with the feeding of rice straw to buffaloes and is considered endemic to regions where rice is cultivated. Cases are concentrated in winter when conditions favor fungal growth in inadequately stored straw. Degnala is characterized by necrosis and gangrene of the extremities, including the tail, lower limbs, ears, tongue, muzzle, and teats. The pelvic limbs are more affected than the thoracic limbs. A tortuous appearance of the tail is very common, and cracks or corneal loss of the hooves may occur, exposing the blades and even the bones. There is no diagnostic method for identifying the disease in animals other than clinical and epidemiological criteria, combined with fungal culture samples. There is no treatment that neutralizes the effects of the toxins; the current treatment is palliative and supportive, consisting of pentasulfate solution, anti-Degnala liquid, 2% nitroglycerin ointment, and broad-spectrum antibiotics for secondary infections. Additionally, the management of drying and proper storage of straw is essential for controlling this disease.

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Cases of diphtheria, even in immunized individuals, are still reported in several parts of the world, including in Brazil. New outbreaks occur in Europe and other continents. In this context, studies on Corynebacterium diphtheriae infections are highly relevant, both for a better understanding of the pathogenesis of the disease and for controlling the circulation of clones and antimicrobial resistance genes. Here we present a case of cutaneous infection by multidrug-resistant Corynebacterium diphtheriae and provide its whole-genome sequencing. Genomic analysis revealed resistance genes, including tet(W), sul1, cmx, rpoB2, rbpA and mutation in rpoB. We performed phylogenetic analyzes and used the BRIG to compare the predicted resistance genes with those found in genomes from other significant isolates, including those associated with some outbreaks. Virulence factors such as spaD, srtBC, spaH, srtDE, surface-anchored pilus proteins (sapD), nonfimbrial adhesins (DIP0733, DIP1281, and DIP1621), embC and mptC (putatively involved in CdiLAM), sigA, dtxR and MdbA (putatively involved) in post-translational modification, were detected. We identified the CRISPR-Cas system in our isolate, which was classified as Type II-U based on the database and contains 15 spacers. This system functions as an adaptive immune mechanism. The strain was attributed to a new sequence type ST-928, and phylogenetic analysis confirmed that it was related to ST-634 of C. diphtheriae strains isolated in French Guiana and Brazil. In addition, since infections are not always reported, studies with the sequence data might be a way to complement and inform C. diphtheriae surveillance.

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Bacillus cereus is rarely implicated when diarrheal cases in children are diagnosed in developing countries due to the lack of molecular methods to identify its enterotoxigenic genes. We report that out of 62 enterobacteria isolated from 70 stool samples collected from children hospitalized at the Mile 4 Hospital, Ebonyi State, Nigeria, 24 isolates were identified as B. cereus based on 16SrRNA gene sequence. The enterotoxins genes nheA and cytK2 were detected in 23 out of the 24 isolates, while hblC was detected in 19 isolates. B. cereus may be responsible for greater number of yearly incidences of acute childhood gastroenteritis in Nigeria.

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E. coli is considered one of the most important zoonotic pathogens worldwide. Highly virulent and antimicrobial-resistant strains of E. coli have been reported in recent years, making it essential to understand their ecological origins. In this study, we analyzed the characteristics of E. coli strains present in the natural population of American bison (Bison bison) in Mexico. We sampled 123 individuals and determined the presence of E. coli using standard bacteriological methods. The isolated strains were characterized using molecular techniques based on PCR. To evaluate the diversity of E. coli strains in this population, we analyzed 108 suggestive colonies from each fecal sample. From a total of 13,284 suggestive colonies, we isolated 33 E. coli strains that contained at least one virulence gene. The virotypes of these strains were highly varied, including strains with atypical patterns or combinations compared to classical pathotypes, such as the presence of escV, eae, bfpB, and ial genes in E. coli strain LMA-26-6-6, or stx2, eae, and ial genes in E. coli strain LMA-16-1-32. Genotype analysis of these strains revealed a previously undescribed phylogenetic group. Serotyping of all strains showed that serogroups O26 and O22 were the most abundant. Interestingly, strains belonging to these groups exhibited different patterns of virulence genes. Finally, the isolated E. coli strains demonstrated broad resistance to antimicrobials, including various beta-lactam antibiotics.

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Maize grain samples collected from 129 small-scale farmers' stores in southern and southwestern Ethiopia were analysed by LC-MS/MS for a total of 218 mycotoxins and other fungal metabolites of which 15% were regulated mycotoxins. Mycotoxins produced by Penicillium, Aspergillus, and Fusarium accounted for 31%, 17%, and 12% of the metabolites, respectively. Most of the current samples were contaminated by masked and/or emerging mycotoxins with moniliformin being the most prevalent one, contaminating 93% of the samples. Each sample was co-contaminated by 3 to 114 mycotoxins/fungal metabolites. Zearalenone, fumonisin B1, and deoxynivalenol were the dominant mycotoxins, occurring in 78%, 61%, and 55% of the samples with mean concentrations of 243, 429, and 530 µg/kg, respectively. The widespread co-occurrence of several mycotoxins in the samples may pose serious health risks due to synergistic/additional effects.

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Fusarium verticillioides causes significant decrease in corn yield and quality, and produces fumonisins, which represent a serious risk to human and animal health. Bacillus species can be an effective and environmentally friendly alternative for F. verticillioides biological control. In this study, some properties of cell-free supernatants (CFSs) of two Bacillus spp. identified as Bacillus subtilis (NT1, NT2) as well as the antifungal effect against F. verticillioides 97L were evaluated. B. subtilis NT1 and NT2 were isolated from commercially available fermented whole soybeans (Natto). Antifungal activity was observed in both CFSs of B. subtilis isolates (50-59 mm) obtained by co-culture suggesting that antifungal compound production depends on interaction between bacteria and fungi. Cell-free supernatants from the two B. subtilis isolates inhibited mycelial growth (77%-94%) and conidial germination (22%-74%) of F. verticillioides 97L. In addition, CFSs caused significant morphological changes such as distorted and collapsed hyphae with wrinkled surfaces and the presence of a large amount of extracellular material compared to the control without CFSs. Both B. subtilis isolates (NT1 and NT2) produced extracellular proteases, biosurfactants and polar low molecular weight compounds that probably act synergistically and may contribute to the antifungal activity. Antifungal compounds showed heat and pH stability and resistance to proteolytic enzymes. Furthermore, antifungal compounds showed high polarity, high affinity to water and a molecular weight less than 10 kDa. These results indicated that the two B. subtilis (NT1 and NT2) have potential as biocontrol agents for F. verticillioides.

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This study compared the performance of two commercial molecular assays, the STANDARD M10 Clostridioides difficile assay (M10) and the Xpert C. difficile assay (Xpert), for detecting toxigenic C. difficile in stool specimens. A total of 487 consecutive stool specimens submitted for routine C. difficile testing between June and November 2023 were included. Following routine testing using C. DIFF QUIK CHEK COMPLETE (QCC), M10 and Xpert were tested in parallel, alongside toxigenic culture (reference standard). Additionally, two-step algorithms, using QCC on the first step and either M10 or Xpert on the second step, were assessed. Both M10 and Xpert demonstrated a sensitivity and negative predictive value (NPV) of 100%. M10 exhibited significantly higher specificity and positive predictive value (PPV; 91.9% and 64.2%, respectively) than Xpert (90.3% and 59.8%, respectively). Both two-step algorithms showed a sensitivity and NPV of 98.4% and 99.8%, respectively. The specificity and PPV of the two-step algorithm using M10 (95.2% and 75.0%, respectively) were slightly higher than those of the one using Xpert (94.8% and 73.2%, respectively), without statistical significance. Receiver operating characteristic curve analysis, assessing the predictive ability of cycle threshold (Ct) values for the detection of free toxin, exhibited an area under the curve of 0.825 for M10 and 0.843 for Xpert. This indicates the utility of Ct values as predictors for the detection of free toxin in both assays. In conclusion, M10 proves to be an effective diagnostic tool with performance comparable to Xpert, whether utilized independently or as part of a two-step algorithm.

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Sweating is one of the most important processing methods of Chinese medicinal herbs. However, the high temperature and humidity environment required for sweating Chinese medicinal herbs makes it very easy for fungi to breed, especially toxigenic fungi. The mycotoxins produced by these fungi will then contaminate the Chinese medicinal herbs. In this study, we explored the changes in mycobiota, toxigenic fungi, and mycotoxins with and without sweating in Radix Dipsaci (RD), a typical representative of traditional Chinese medicine that requires processing through sweating. We also isolated and identified the toxigenic fungi from RD, whether they were subjected to sweating treatment or not, and examined their toxigenic genes and ability. The results showed that the detection rate of mycotoxins (aflatoxins, ochratoxins, zearalenone, and T-2 toxin) in RD with sweating was 36%, which was 2.25-fold higher than that in RD without sweating. We also detected T-2 toxin in the RD with sweating, whereas it was not found in the RD without sweating. The sweating process altered the fungal composition and increased the abundance of Fusarium and Aspergillus in RD. Aspergillus and Fusarium were the most frequently contaminating fungi in the RD. Morphological and molecular identification confirmed the presence of key toxigenic fungal strains in RD samples, including A. flavus, A. westerdijkiae, F. oxysporum and F. graminearum. These four fungi, respectively, carried AflR, PKS, Tri7, and PKS14, which were key genes for the biosynthesis of aflatoxins, ochratoxins, zearalenone, and T-2 toxin. The toxigenic ability of these four fungal strains was verified in different matrices. We also found that A. flavus, A. westerdijkiae, and F. oxysporum were isolated in RD both with sweating and without sweating, but their isolation frequency was significantly higher in the RD with sweating than in the RD without sweating. F. graminearum was not isolated from RD without sweating, but it was isolated from RD with sweating. These findings suggest that the sweating process promotes the expansion of toxigenic fungi and increases the risk of combined mycotoxin contamination in RD.

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Fifty-four maize grain samples freshly harvested from subsistence farmers' fields in southwestern Ethiopia were analyzed for multiple mycotoxins using liquid chromatography-tandem mass spectrometric (LC-MS/MS) method following extraction by acetonitrile/water/acetic acid on a rotary shaker. The grain samples were contaminated with a total of 164 metabolites, of which Fusarium and Penicillium metabolites were the most prevalent accounting for 27 and 30%, respectively. All the major mycotoxins and derivatives except one (citrinin) were of Fusarium origin. Zearalenone was the most frequent major mycotoxin occurring in 74% of the samples at concentrations of 0.32-1310 µg/kg. It was followed by nivalenol (63%), zearalenone-sulfate (44%), and fumonisin B1 (41%). Nivalenol, nivalenol glucoside, and fusarenon-X were detected at unusually high levels of 8-1700 µg/kg, 21-184 µg/kg, and 33-149 µg/kg, respectively. Deoxynivalenol and DON-3 glucoside contaminated 32% of the samples, each at levels of 15.9-5140 µg/kg and 10-583 µg/kg, respectively. Moniliformin and W493B occurred in 96 and 22% samples at levels of 3.27-4410 µg/kg and 3-652 µg/kg, respectively. Fumonisins were also detected in the samples at levels of 9-6770 µg/kg (B1), 16-1830 µg/kg (B2), 9.5-808 µg/kg (B3), and 1.3-128 µg/kg (A1). This study confirmed the presence of an array of mycotoxins contaminating maize grains right from the field. The effect of the co-occurring mycotoxins on consumers' health should be investigated along with that of the newly emerging ones. Results of the current study call for application of pre-harvest mycotoxin mitigation strategies to safeguard maize-based food and feed.

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This study aimed to evaluate the antifungal effect of SC319 sorghum phenolic extract (SPE) on the Aspergillus, Fusarium, Penicillium, Stenocarpella, Colletotrichum, and Macrophomina genera. SPE was extracted by 20% ethanol and used in four assays: (1) against Fusarium verticillioides in solid (PDA) and liquid (PD) potato dextrose media; (2) Minimum Inhibitory Concentration (MIC) assay with 16 fungi isolates; (3) Conidial Germination Rate (CGR) with 14 fungi isolates and (4) Growth Curve (GC) with 11 fungi isolates. There was no reduction in the mycelial growth (colony diameter and dry weight) and in the number of Fusarium verticillioides spores in assay 1 (PDA and PD). The colony's dry weight was almost six times higher in the presence than in the absence of SPE. All SPE samples presented MIC (assay 1) above the maximum concentration tested (5000 µg.mL-1) for the 16 isolates. Also, there was no inhibitory effect of SPE on conidia germination rate (CGR). Oppositely, in GC assay, the control had a higher CFU count than the samples with SPE in 24 h. This result suggests that SPE can delay the fungal growth in the first hours of incubation, which is an important finding that may help reduce the severity of fungal diseases in plants. However, further studies are needed to confirm these results, including sorghum genotypes with different profiles of phenolic compounds. Although the SC319 SPE was not effective as an antifungal agent, it may have potential as a growth promoter of beneficial fungi in the food and pharmaceutical industries.

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Maize is an important crop for the Republic of Moldova and one of the crops most contaminated with mycotoxins. Maize grain obtained from plants cultivated on Moldavian cornfields in 2021 and 2022 were tested for mycotoxigenic risk using qPCR with primers to several fungal genome sequences engaged in mycotoxin synthesis and ELISA test to screen total aflatoxins, fumonisin B1, zearalenone, deoxynivalenol and T-2 toxin. Except for T-2 toxin, the mycotoxin concentrations were under the limits of detection and did not exceed maximum admissible levels for unprocessed grain. Concentrations of T-2 toxin in grain samples did not correlate significantly with the quantity of toxigenic F. sporotrichioides. All of the analysed grain samples were contaminated with at least one toxigenic fungus, and 20% of the samples were infected with seven different species of toxigenic fungi. Accumulation of fungi in maize kernels was affected significantly by the season, and generally a decrease was observed in fungal frequency and quantity under drought conditions. However, several toxigenic Aspergillus and Fusarium fungi that are able to produce aflatoxins and fumonisins under improper storage conditions were found in the kernels during the whole period of monitoring.

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Sichuan bacon represents the most prevalent dry-cured meat product across Southwest China, but it is vulnerable to fungal spoilage. In the present study, a total of 47 Sichuan bacons were obtained from different regions of the Sichuan Province and analyzed for the presence of ochratoxin A (OTA), yielding a positive rate of 23.4 % (11/47). All the observed OTA concentrations exceeded the maximum admissible dose in meat products (1 µg/kg) established by some EU countries, with the highest OTA concentration being 250.75 µg/kg, which raises a food safety concern and reveals the need for a standardized scientific processing protocol. Then, an OTA-producing fungus named 21G2-1A was isolated from positive samples and found to be Aspergillus westerdijkiae. Further characterization suggested a positive correlation between fungal growth and OTA production. The optimal temperature for the former was 25 °C, while it was 20 °C for the latter. Although the A. westerdijkiae strain 21G2-1A demonstrated greater mycelium growth in the presence of NaCl, OTA production was significantly dismissed when the salinity was greater than 5 %. Four lactic acid bacteria (LAB) were screened out as antagonists against the ochratoxigenic fungus. In vitro evaluation of the antagonists revealed that live cells inhibited fungal growth, and adsorption also contributed to OTA removal at different levels. This study sheds some light on OTA control in Sichuan bacon through a biological approach.

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Background: Classical toxin-mediated respiratory diphtheria has become less common because of widespread effective vaccination globally but invasive disease as a result of non-toxigenic strains of Corynebacterium diphtheriae is not prevented by vaccination and may result in severe disease, including infective endocarditis (IE). Objectives: To describe the outbreak and subsequent investigation of a cluster of five cases of non-toxigenic C. diphtheriae endocarditis. Method: A retrospective observational case series of five cases of non-toxigenic C. diphtheriae endocarditis identified in the rural West Coast district of the Western Cape province of South Africa between May 2021 and June 2021. Results: Non-toxigenic C. diphtheriae IE had an aggressive clinical course with high mortality in this cohort. Only one of five patients survived to hospital discharge. The surviving patient received a prompt diagnosis with early surgical intervention but still had a complicated clinical course. Notably, only one case had a pre-existing risk factor for IE, namely a prosthetic valve. Whole genome sequencing of clinical isolates confirmed that all isolates were of the same novel sequence type of non-toxigenic C. diphtheriae but despite a thorough investigation no epidemiological link was ever found between the cases. Conclusion: Non-toxigenic strains of C. diphtheriae are less well known but may be highly virulent and cause severe invasive disease. Contribution: This is the largest cluster of non-toxigenic C. diphtheriae IE ever described in South Africa and expands the body of literature on this unusual but possibly emerging infection.

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The objective of this trial was to evaluate how broilers responded to Aspergillus flavus strains that are toxigenic and atoxigenic. The study included four treatments in a 2 × 2 factorial design, with six replicates of 10 birds each. As a result of this study measuring feed intake (FI), weight gain (WG), feed conversion ratio (FCR), crude protein, ether extract, and crude fibre, the interaction was insignificant between the toxigenic and atoxigenic diets (P > 0.05). Consumption of toxigenic aflatoxin B1-500 ppb diet decreased FI and WG but increased FCR, and cost to produce live broiler weight (P < 0.05) compared to the control diets. The addition of atoxigenic strains to contaminated diets significantly offset (P < 0.05) the effects. Diets with or without 500 ppb toxigenic and atoxigenic A. flavus did not affect the relative weight g/100gBW of pancreas, gizzard and bursa of Fabricius. Dietary inclusion of 500 ppb toxigenic Aspergillus spp. increased the relative weight (P < 0.05) of the kidney, liver, spleen and thymus while atoxigenic dietary addition reduced the relative weight of the same organs (P < 0.05). Dietary inclusion of toxigenic and atoxigenic Aspergillus spp. did not significantly affect the haematological parameters measured (P < 0.05). Dietary inclusion of 500 ppb toxigenic Aspergillus elevated the urea, creatine, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in the serum of the broilers (P < 0.05). A decrease was observed when atox igenic A. flavus was used in the intervention for urea, creatinine and AST (P < 0.05), whereas an insignificant reduction was observed for ALT and ALP (P ≤ 0.05). This study concluded that dietary atoxigenic strain improved broiler performance, digestibility, and blood parameters.

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BACKGROUND: Bacillus cereus is implicated in severe foodborne infection in humans. This study intended to assess the occurrence, groEL gene sequencing, biofilm production, and resistance profiles of emerged multidrug resistant (MDR) B. cereus in meat and meat product samples. Moreover, this work highlights the virulence and toxigenic genes (hblABCD complex, nheABC complex, cytK, ces, and pc-plc) and antimicrobial resistance genes (bla1, tetA, bla2, tetB, and ermA). METHODS: Consequently, 200 samples (sausage, minced meat, luncheon, beef meat, and liver; n = 40 for each) were indiscriminately collected from commercial supermarkets in Port Said Province, Egypt, from March to May 2021. Subsequently, food samples were bacteriologically examined. The obtained isolates were tested for groEL gene sequence analysis, antibiotic susceptibility, biofilm production, and PCR screening of toxigenic and resistance genes. RESULTS: The overall prevalence of B. cereus among the inspected food samples was 21%, where the highest predominance was detected in minced meat (42.5%), followed by beef meat (30%). The phylogenetic analysis of the groEL gene exposed that the examined B. cereus strain disclosed a notable genetic identity with other strains from the USA and China. Moreover, the obtained B. cereus strains revealed ß-hemolytic activity, and 88.1% of the recovered strains tested positive for biofilm production. PCR evidenced that the obtained B. cereus strains usually inherited the nhe complex genes (nheA and nheC: 100%, and nheB: 83.3%), followed by cytK (76.2%), hbl complex (hblC and hblD: 59.5%, hblB: 16.6%, and hblA: 11.9%), ces (54.7%), and pc-plc (30.9%) virulence genes. Likewise, 42.9% of the examined B. cereus strains were MDR to six antimicrobial classes and encoded bla1, bla2, ermA, and tetA genes. CONCLUSION: In summary, this study highlights the presence of MDR B. cereus in meat and meat products, posing a significant public health risk. The contamination by B. cereus is common in minced meat and beef meat. The molecular assay is a reliable fundamental tool for screening emerging MDR B. cereus strains in meat and meat products.

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