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Infecting to Melissococcus plutonius, the primary cause of the European foulbrood (EFB) disease, can be followed by infecting to the secondary bacteria, such as Enterococcusfaecalis and Brevibacillus laterosporus. The aim of this research was to diagnose EFB disease by tracking the causes of the disease in apiaries all over Iran. From 260 apiaries, honey bee samples were randomly collected. After samples preparation, the genomic DNA was extracted and specific primers were selected for interested bacteria. Using the conventional polymerase chain reaction (PCR) method for E. faecalis and B. laterosporus and nested-PCR method for M. plutonius, the target fragments were amplified. Desired standard bacteria and distilled water were used as positive and negative controls, respectively. Results showed that out of 260 samples from apiaries, 74 and three samples were positive for E. faecalis and B. laterosporus bacteria, respectively. Also, the results of nested-PCR showed that 58 samples were positive, of which only 12 samples were positive in the evaluation of E. faecalis. Results demonstrated that the highest and the least levels of the infection for M. plutonius and E. faecalis were in the south and east of the country, respectively. Results indicated that sometimes due to the excessive growth of secondary bacteria, the main bacteria can be removed from the environment. Also, findings proposed that those provinces with higher number of populations, followed by higher amount of air pollution, had more infected samples than others. [ABSTRACT FROM AUTHOR]

ABSTRACT Pro‐biogenic is a recent terminology widely used for products that combine biogenic materials and probiotics which has made progressive improvement in a new era of research on functional foods. This study aimed to develop functional ice cream with Bacillus coagulans and propolis extract (PE) as a biogenic part to develop ice cream's physiochemical and antioxidant characteristics. Five probiotic ice cream samples were prepared using different levels of PE powder (0%, 0.2%, 0.4%, 0.6%, and 0.8% w/w), and the physicochemical, total phenol content (TPC), antioxidant and sensory properties, and probiotic survival of the samples were examined. The study found that PE levels did not significantly impact fat, protein, carbohydrate, and ash content, overrun, melting rate, and adhesiveness of probiotic ice cream, but increased dry matter, apparent viscosity, and hardness. Adding PE to freeze‐storage samples significantly (p < 0.05) reduced pH and improved TPC and antioxidant activity. The prepared ice cream containing probiotic bacteria and PE extracts, despite their darker and yellower color, were acceptable based on sensory evaluation. Furthermore, the survival of probiotic bacteria in the ice cream, with different levels of PE appeared to be in acceptable limits (107 CFU/g). The findings of the research indicated that the pro‐biogenic ice cream has good functionality and incorporating a PE aside probiotic could improve physiochemical and antioxidant characteristics which can be used as a value‐added ingredient in the formulation of functional pro‐biogenic ice creams. [ABSTRACT FROM AUTHOR]

Abstract This study highlights the cytotoxic effect of three L. casei strains on colorectal cell lines in invitro conditions. Different concentrations of live, heat killed (HK) and cell free supernatant (CFS) of three L.casei strains were subjected to CaCo2 and MRC5 cell lines. The viability of the treated and untreated cells was determined after 72 hrs by MTT assay, and IC50 estimated. Apoptosis was evaluated by Annexin V-propidium iodide method using flow cytometry. The live, HK and CFS of the L. casei strains showed cytotoxic effects on colorectal cell lines with significant differences. The cytotoxicity effects of live cells on CaCo2 cells were significantly higher (p˂0.01) than the HK cells. A dose dependent response was observed, as higher concentrations resulted in enhanced cytotoxicity effects. Live L.casei 1296-2cells inhibited 91% of CaCo2 cell growth, with IC50 of less than 108 cfu/ml. MRS medium and concentrations of CFS at above 20% v/v, were cytotoxic to the normal cell lines. Flow cytometry analyses of L. casei 1296-2 indicated that cytotoxicity effects on CaCo2 cells is related to apoptotic induction. Invitro studies indicate that Live and CFS of L. casei 1296-2 might be promising candidate for the control of colorectal cancers.

The pathogenesis of Mycobacterium tuberculosis (Mtb) is related to its low molecular weight proteins mainly ESAT6 and CFP10 that are highly specific and potentially useful for the diagnosis of tuberculosis. This research focused on isolation, purification, and characterization of low molecular weight proteins from Mtb. Cultures of Mtb were inactivated by heating at 68 °C for 90 min and 100 °C for 3 hrs, respectively. Inactivated cultures were filtered and the proteins in the supernatant fluid precipitated with two rounds of ammonium sulfate, at 4 °C. The collected precipitates were dialyzed and subjected to gel chromatography (G-50) and the obtained fractions were analyzed for protein concentrations and molecular weight. ESAT6 and CFP10 protein complex in the purified fraction was confirmed by Western blotting. Guinea pig sensitization assay was used for estimating the potency of the purified fraction compared to the standard PPD. The maximum amount of low molecular weight proteins were precipitated by 20% ammonium sulfate. SDS-PAGE analysis revealed protein bands of approximately 10-15 kDa. The purity of the proteins was ≥95%, as confirmed by SDS-PAGE. The presence of the ESAT-6/CFP10 complex was confirmed by Western blot analysis. The purified fractions showed no cross-reaction with BCG or M. avium strain. ESAT-6/CFP-10 purified by the ammonium sulfate method appeared to be suitable for the development of a diagnostic kit for the detection of Mtb. [ABSTRACT FROM AUTHOR]

Background and Objectives: Bovine tuberculosis diagnosis is usually performed by various tests with specific limitations. Mycobacterium bovis culture filtrate contains antigenic proteins that could be used to improve the sensitivity of bovine tuberculosis diagnosis. The objective of this study was to identify and purify antigenic proteins from culture filtrates of M. bovis strain AN5 for use in immunological assays. Materials and Methods: Secreted proteins were purified from the heat-treated culture filtrate of M. bovis strain AN5. Proteins were precipitated with ammonium sulfate, fractionated by Sephadex G50 chromatography. The protein concentrations and the approximate molecular weight were determined by lowry method and 12% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Immunological methods, including dot-blotting and western blotting, assessed the quality of the isolated proteins. Results: The quantity of antigenic proteins in the culture medium was measured at far more than 15% of the amount of proteins secreted into medium. Three main chromatographic fractions obtained and showed concentrations of proteins ranging from 14 to 60 µg/µl with molecular weights in the 10 to 180 kDa range. The purified antigens showed positive reactions to the infected cattle serum throughout dot-blotting. Western blotting revealed a total of 15 to 70 kDa molecular weight proteins. Conclusion: Immunoblotting analysis made it possible to detect and recognize novel antigens that are useful for bovine tuberculosis diagnosis improvement. This is significant since non-specific reactions were not observed when we utilized serum of cattle experimentally infected with M. bovis as a polyclonal antibody. [ABSTRACT FROM AUTHOR]

The species of Lactic acid bacteria are known to confer beneficial effects on the host by inhabiting in their gastrointestinal tract (GIT). They succeed in surviving the harsh conditions of the GIT by exhibiting strong tolerance against gastric acids, digestive enzymes and bile simultaneously antagonizing the pathogens by production of antimicrobials. This study has been conducted to elaborate these probiotic characteristics in vivo for which mice were intragastrically given a probiotic approved dose of 1011cfu/ml for 4 days to assess the persistence of two probiotic candidates Lactobacillus plantarum Lp36 and Lactobacillus plantarum Lp86. The fecal count of the test probiotic candidates were seen to persist well in the GIT for 15 days with a count ranging between 104-108cfu/mg of feces (p>0.01). The safety assessment of L. plantarum Lp36 in healthy and S. typhi in infected mice showed an increase in cell count from (day zero of inoculation) 106cfu/100mg of feces to108cfu/100mg (p>0.01) which was maintained till day six, suggesting the persistence in the GIT. The sections of the mice intestinal lining under scanning electron microscope revealed the adherence of Lp36 and Lp86 to the intestinal epithelia. The mice did not show any adverse effect on its health. These findings make our strains promising probiotic candidates to be used to promote health benefits after further assessments. [ABSTRACT FROM AUTHOR]

Background and Objectives: Human milk is a continuous supply of Lactic Acid bacteria (LAB), including enterococci with probiotic potentials. The aim of this study was to analyze two Enterococcus species, isolated from human milk for their probiotic potential, bacteriocin producing ability and virulence traits. Materials and Methods: Enterococcus faecium TA0033 and E. faecalis TA102 were tested for acid and bile tolerance, survival in simulated gastric and intestinal conditions. The antibacterial spectrum of the isolates was tested by agar well diffusion assay. The antagonistic agent was characterized by physico-chemical methods. The enterocin structural genes, virulence determinants, vancomycin resistance and biogenic amine genes, such as hdc1, hdc2, tdc, ldc and odc were also determined. Results: The tested isolates survived acidic conditions, high bile salt (1%), simulated gastric and intestinal conditions. The culture supernatant fluids of the two isolates inhibited the growth of Escherichia coli, Listeria monocytogenes, Salmonella typhi, Staphylococcus aureus, Shigella dysenteriae and Streptococcus agalactiae. The antagonistic activity was lost in the presence of proteolytic enzymes but tolerated the action of catalase, lysozyme and lipase. In contrast to enterocin TA102, enterocin TA0033 possessed bactericidal mode of action. Bacteriocin structural genes, entA and entB were present in the genome of the two isolates, while E. faecalis TA102 additionally harboured entP and bac31 genes. The phenotypic and genotypic virulence assessment studies indicated hyaluronidase (hyl) production and vancomycin resistance in E. faecalis TA102 while, none of the isolates harboured the biogenic amine genes. Conclusion: The presence of virulence genes in E. faecalis TA102 calls for careful monitoring of Enterococcus isolates for their safety parameters. [ABSTRACT FROM AUTHOR]