Effects of Probiotic Saccharomyces boulardii Supernatant on Viability, Nano-Mechanical Properties of Cytoplasmic Membrane and Pro-Inflammatory Gene Expression in Human Gastric Cancer AGS Cells.

BACKGROUND: Gastric cancer has been recognized as the second most probable cause of death in humans from cancer diseases around the world. Postbiotics, supernatant, and metabolites from probiotic microorganisms have recently been used widely to prevent and treat cancer diseases in humans, without any undesirable side effects. This study explores the antiproliferative and antitumor activities of the probiotic Saccharomyces cerevisiae var. boulardii supernatant (SBS) against AGS cancer cells, a human gastric adenocarcinoma cell line. METHODS: We evaluated cell growth inhibitory and mechanical properties of the cytoplasmic membrane and the downregulation of survivin and proinflammatory genes in AGS cells treated with SBS after 24 and 48 h. RESULTS: SBS significantly inhibits the AGS cell growth, and the concentrations with IC50 values after 24 and 48 h treatments are measured as 2266 and 1956 µg/mL, respectively. Regarding the AFM images and Young`s modulus analysis, SBS significantly induces morphological changes in the cytoplasmic membrane of the treated AGS cells. Expression of survivin, NFƙB, and IL-8 genes is significantly suppressed in AGS cells treated with SBS. CONCLUSIONS: Considering the antitumor activities of SBS on AGS cell line, it can be regarded as a prospective therapeutic and preventive strategy against human stomach cancer disease.

ACE2-Inhibitory Effects of Bromelain and Ficin in Colon Cancer Cells.

Background and Objectives: Bromelain and ficin are aqueous extracts from fruits of Ananas comosus and Ficus carcia plants, used widely for medical applications. Angiotensin-converting enzyme 2 (ACE2) is a homolog of ACE, degrading Ang II to angiotensin 1-7 and decreasing the cellular concentration of Ang II. Materials and Methods: In this study, we investigated the ACE2-inhibitory, antiproliferative, and apoptosis-inducing effects of ficin and bromelain on caco-2 cells. Results: We found that bromelain and ficin significantly reduced the viability of human colon cancer cells with IC50 value concentrations of 8.8 and 4.2 mg/mL for bromelain after 24 and 48 h treatments, and 8.8 and 4.2 mg/mL for ficin after 24 and 48 h treatments, respectively. The apoptosis of the caco-2 cell line treated with bromelain was 81.04% and 56.70%, observed after 24 and 48 h. Total apoptotic proportions in caco-2 cells treated with ficin after 24 and 48 h were 83.7% and 73.0%. An amount of 1.6 mg/mL of bromelain and ficin treatments on caco-2 cells after 24 h revealed a higher decrease than that of other concentrations in the expression of ACE2 protein. Conclusions: In conclusion, bromelain and ficin can dose-dependently decrease the expression of ACE2 protein in caco-2 cells.

A quantitative prevalence of Escherichia coliO157 in different food samples using real-time qPCR method.

Escherichia coli serogroup O157 is the main causative agent of several intestinal and extra-intestinal foodborne diseases in humans through consumption of low-dose contaminated foods such as milk, beef, and vegetables. To date, studies regarding the quantitative prevalence of E. coli O157 in foods are so limited. Therefore, this study aimed to evaluate the quantitative prevalence rate of E. coli serogroup O157 in raw milk (n = 144), vegetable salad (n = 174), and minced beef samples (n = 108) using the real-time qPCR SYBR green melting curve method targeting the rfbA gene. First, we evaluated the method and found a sensitive and specific qPCR assay with 1 log of CFU/ml detection limit to detect E. coli O157 (Tm = 80.3 ± 0.1°C). About 2.77%, 10.18%, and 9.19% of raw milk, minced beef, and vegetable salad samples, respectively, were contaminated with E. coli O157. Minced beef and vegetable salad samples were significantly more contaminated than raw milk samples. Population average of E. coli O157 in raw milk, minced beef, and vegetable salad samples were 2.22 ± 0.57, 3.30 ± 0.40, and 1.65 ± 0.44 log CFU/ml or gr, respectively. Significantly higher levels of population of E. coli O157 were observed in minced beef samples. Minced beef can be regarded as the main food in the transmission of this foodborne pathogen. Routine quantitative rapid monitoring is strongly suggested to be carried out to prevent foodborne diseases caused by E. coli O157.

Anticancer Properties of Saccharomyces boulardii Metabolite Against Colon Cancer Cells.

Saccharomyces cerevisiae var. boulardii has been used as a probiotic yeast in the medical and food industries. Colon cancers have been known as the third most common cancer type worldwide. Nowadays, cell-free extract and metabolites of probiotics have been employed for the treatment or prevention of different cancer diseases. This study investigates the anticancer properties of S. boulardii metabolites against human colon carcinoma. We evaluated cytotoxicity, apoptosis induction, and suppression of survivin, IL-8, and NFƙB gene expression effects of SBM against caco-2 cells after 24 and 48 h. IC50 concentrations of SBM were measured at 815 and 1411 µg/mL for 24 and 48 h treatments, respectively. The total proportion of apoptotic caco-2 cells treated with SBM after 24 and 48 h were calculated at 62.23 and 88.7%, respectively. Also, relative expression of survivin, IL-8, and NFƙB genes were significantly suppressed in caco-2 cells treated with SBM after 24 and 48 h. In conclusion, we found that SBM induced apoptosis, inhibited the growth rate, and suppressed the expression of the survivin, IL-8, and NFƙB genes in human colorectal cancer cells and it can be considered as a perspective supplement or drug for the treatment or prevention of colon cancer in humans.

Prevalence of foodborne and zoonotic viral pathogens in raw cow milk samples.

Foodborne and zoonotic viral pathogens are responsible for substantial morbidity and mortality worldwide. These viruses can be transmitted through foods such as dairy products to humans and cause several acute and chronic diseases. This study aimed to investigate the prevalence and profile of different foodborne and zoonotic viruses in raw cow milk samples. We collected 492 raw cow milk samples from local dairy markets in Qazvin, Iran. Then we evaluated the presence of hepatitis A virus, noroviruses, rotavirus, astrovirus, bovine leukaemia virus (BLV) and tick-borne encephalitis virus (TBEV) in samples using conventional and nested reverse transcription-polymerase chain reaction methods. We found that 34.95, 7.72, 25.81, 14.63, 66.86, 12.80 and 21.34% of raw milk samples were contaminated with norovirus GI, norovirus GII, hepatitis A virus, rotavirus, astrovirus, BLV and TBEV viruses, respectively. Interestingly, the samples collected from the city's south area revealed a higher prevalence of foodborne and zoonotic viruses. Astrovirus and its combination with norovirus GI were the most prevalent virus profiles. Also, the highest correlations were observed among the presence of rotavirus and hepatitis A viruses (0.36) and TBEV and norovirus GII (0.31). Considering the prevalence rate and virus profiles of different foodborne and zoonotic viruses in raw milk samples, hygiene practices and the pasteurization process are strongly suggested to be conducted throughout the cow milk production chain and in dairy industries to prevent infections with these pathogens.

Antibiotic Resistance and Molecular Characterization of Cronobacter sakazakii Strains Isolated from Powdered Infant Formula Milk.

BACKGROUND: Cronobacter sakazakii is a new emerging foodborne bacterial pathogen associated with severe lethal diseases such as meningitis, necrotizing enterocolitis, and septicemia in infants and neonates. Powdered infant formula milk (PIFM) has been recognized as one of the main transmission vehicles and contaminated sources of this pathogen. This study aimed to investigate the prevalence rate, genotypic and phenotypic antibiotic resistance profile, and clonal relatedness of C. sakazakii strains isolated from 364 PIFM samples collected from Tehran city, Iran. METHODS: Culture-based methods, Kirby-Bauer disk diffusion antibiotic resistance testing, conventional Polymerase Chain Reaction (PCR), and Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR) assays were used in this study to detect and characterize the C. sakazakii isolates. RESULTS: We isolated 25 C. sakazakii strains from PIFM samples (6.86%). The isolates were highly resistant to amoxicillin-clavulanic acid, amoxicillin, ampicillin, cefoxitin, cefepime, erythromycin, ceftriaxone, ciprofloxacin, and chloramphenicol and susceptible to gentamicin, tetracycline, norfloxacin, and azithromycin antibiotics. The blaCTX-M-1 gene was detected in 96% of the isolates. The isolates were categorized into eight distinct clonal types using the ERIC-PCR method, showing a high genetic diversity among the isolates. However, there was a significant correlation between the genotypic and phenotypic antibiotic resistance properties of the isolates. CONCLUSIONS: Novel microbial surveillance systems for detecting multi-drug-resistant C. sakazakii are required to control the contamination of this foodborne pathogen in infant foods.

Anticancer Properties of Probiotic Saccharomyces boulardii Supernatant on Human Breast Cancer Cells.

Saccharomyces boulardii, a variety of S. cerevisiae, is used as a probiotic yeast in food and drug industries. However, S. boulardii is an opportunistic pathogen, and the supernatant of this organism has recently been recommended for its health-promoting benefits. Breast cancer is the most frequent cancer disease in women worldwide. The objective of this study was to investigate the effects of S. boulardii supernatant (SBS) on cell viability, inducing apoptosis and suppression of survivin gene expression in MCF-7 and MCF-7/MX as human non-drug-resistant and multidrug-resistant breast cancer cells respectively. The IC50 value of SBS against MCF-7 was calculated 1037, 542, and 543 µg/mL for 24, 48, and 72 h treatments, respectively. Also, this value against MCF-7/MX cells were measured 1242, 616, and 444 µg/mL after 24, 48, and 72 h respectively. We found that suppression of survivin gene expression should be one of the main molecular antitumor mechanisms which is contributed to apoptosis in breast cancer cells. However, anticancer activity of SBS was observed more efficient against MCF-7 than that against MCF-7/MX cells. SBS is suggested to be considered as one of the prospective anticancer drugs to treat human breast carcinoma. More investigations especially in vivo studies are strongly recommended to be implemented to characterize other antitumor mechanisms of SBS against breast carcinoma.

Prevalence, Phylogroups and Antimicrobial Susceptibility of Escherichia coli Isolates from Food Products.

The emergence of multi-drug resistant E. coli is an important matter of increasing considerable concern to global public health. The aim of this study was to investigate the incidence, antibiotic resistance pattern and phylogroups of E. coli isolates obtained from raw milk, vegetable salad and ground meat samples collected from Qazvin Province (Iran). Culture-based techniques, Kirby-Bauer disk diffusion susceptibility testing and PCR assays were used to determine the incidence rate, antimicrobial resistance pattern and phylogenetic groups of the E. coli isolates. The E. coli isolates were highly resistant to amoxicillin (79.1%), trimethoprim-sulfamethoxazole (70.8%), amoxicillin-clavulanic acid (62.5%), tetracycline (54.1%), chloramphenicol (54.1%), nitrofurantoin (54.1%), ampicillin (45.8%), streptomycin (45.8%), and kanamycin (33.3%); and completely susceptible to norfloxacin and azithromycin and 70.8% of the isolates were multi-drug resistant. Most E. coli isolates (46%) belonged to phylogroup A. Novel, practical, efficient food safety control and surveillance systems of multi-drug resistant foodborne pathogens are required to control the foodborne pathogen contamination.

Genetic diversity and antibiotic resistance of Shigella spp. isolates from food products.

The emergence of multidrug-resistant Shigella is a significant threat to global public health. Limited studies have investigated the incidence, antimicrobial susceptibility, and genetic diversity of Shigella isolated from food products. Conventional culture-based, serologic, molecular, disk diffusion, PCR, and RAPD-PCR methods were used to determine the prevalence rate, phenotypic and genotypic antibiotic resistance profile, and genetic diversity of the Shigella isolates from food samples including vegetable salad, ground meat, and raw cow's milk (405 samples). The prevalence rate of Shigella in food samples was 4.44%. The incidence of S. sonnei (3.7%) was higher than that of S. flexneri (0.74%). S. dysenteriae and S. boydii were not detected in food samples examined. Also, no Shigella were recovered from raw cow's milk. This study showed that the Shigella isolates were resistant to sulfamethoxazole/trimethoprim (83.3%), amoxicillin (66.6%), streptomycin (66.6%), tetracycline (61.1%), ampicillin (50%), amoxicillin-clavulanic acid (50%), azithromycin (50%), and chloramphenicol (50%) and completely sensitive to cefoxitin, cefepime, amikacin, and gentamicin. All Shigella isolates were multidrug-resistant. We detected bla SHV resistance gene in all isolates; however, no isolate harbored bla TEM gene. RAPD-PCR categorized the Shigella isolates into five main clusters. The highest antibiotic resistance was observed in the isolates of cluster R4. The finding of this study also indicated an association between antimicrobial resistance profiles and genotyping properties of the isolates. Novel food monitoring systems, including surveillance of multidrug-resistant foodborne pathogens, especially in developing countries, are required to control the foodborne diseases.

Probiotic Saccharomyces cerevisiae var. boulardii supernatant inhibits survivin gene expression and induces apoptosis in human gastric cancer cells.

Natural anticancer drug and compounds with other great benefits are of interest recently due to lower side effects than chemotherapy for cancer treatment and prevention. Different natural and synthetic drugs have been suggested to be used for treatment of gastric cancers, the second deadly cancer worldwide. The aim of this study was to investigate anticancer activity of SBS including inducing apoptosis and inhibition of survivin gene expression in gastric cancer cells. We evaluated cell viability, inducing apoptosis and change in survivin gene expression of EPG85-257P (EPG) and EPG85-257RDB (resistant to Daunorubicin, RDB) cell lines under exposure of SBS after 24, 48, and 72 hr. We found that SBS decreased cell viability, induced apoptosis, and reduced survivin gene expression in treated EPG and RDB cells (with the significant IC50 values of 387 and 575 µg/ml after 72 and 48 hr for EPG and RDB cells respectively). However, we observed SBS was more efficient to induce apoptosis in EPG than RDB cells. We strongly suggest SBS be considered as a prospective anticancer agent or in formulation of complementary medication to treat and prevent gastric cancers.

Genotypic and antimicrobial resistance characterizations of Cronobacter sakazakii isolated from powdered milk infant formula: A comparison between domestic and imported products.

Cronobacter sakazakii, an opportunistic foodborne pathogen and a main cause of meningitis in neonates, is usually isolated from powdered milk infant formula (PMIF). At the present study, C. sakazakii were isolated from imported and domestically produced PMIF samples and identified by detection of ompA gene using real-time PCR SYBR green melting curve following the evaluation of antimicrobial susceptibility and genotyping of the isolates employing BOX-PCR and RAPD methods. We detected totally 5% contamination rate and a significantly higher prevalence of C. sakazakii in bulky imported domestically packaged PMIF samples. Also, our isolates were recognized as multidrug-resistant pathogen completely resistant to ampicillin and amoxicillin; and intermediately resistant to ciprofloxacin and tetracycline antimicrobials. Genotype clustering patterns of bulky imported and imported product isolates were identical by both genotyping methods. Far genetic relatedness of domestic isolate to other isolates and the reference strain indicated higher genetic diversity of the domestic isolate genome. Multidrug resistance and diverse population genetic make complicated situation for determination of strategies for infectious disease prevention.