Effects of two probiotic spores of Bacillus species on hematological, biochemical, and inflammatory parameters in Salmonella Typhimurium infected rats.

Salmonella infections have become a major health concern in recent decades. This pathogen has evolved to become resistant to antibiotics, which has caused problems in its treatment. As such, finding a novel preventive method is important in the treatment and management of this infection. In recent years, uses of probiotics, especially spore-former genera such as Bacillus spp. has become increasingly popular. In this study spores of two probiotic bacteria, Bacillus subtilis and Bacillus coagulans were fed to rats for three weeks through their daily water intake after which Salmonella Typhimurium was gavaged to the rats. On days 1, 3, 5 and 7 after gavaging, the number of Salmonella was counted in liver, spleen, mesenteric lymph nodes, feces and content of ileum and cecum. Hematological and biochemical parameters, inflammatory mediators, total antioxidant capacity and malondialdehyde were also measured. The results showed that B. subtilis and B. coagulans caused delation in infiltration of Salmonella into the lymph nodes, spleen and liver, reduction of the inflammatory mediators, and decreases in oxidative stress, hematological and biochemical changes. The overall count of Salmonella in the above mentioned parameters has also decreased and a faster return to normal base were also witnessed. The results showed that the use of B. subtilis and B. coagulans can potentially help boost the body's immune system, to combat the effects of exposure to the Salmonella pathogen.

The effects of supplementation of Bacillus subtilis and Bacillus coagulans spores on the intestinal microflora and growth performance in rat.

BACKGROUND AND OBJECTIVES: The intestinal microflora has an important role in the health status. Since probiotics can balance the intestinal microflora, they have a lot of health beneficial effects. So the appropriate selection of probiotics can cause health-promoting effects. In this study, the combined effects of Bacillus subtilis and Bacillus coagulans on the intestinal microflora and growth performance in rats were investigated. MATERIALS AND METHODS: 80 male rats were divided into the treatment (receiving 5×107 spores/ml of B. subtilis and 5×107 spores/ml of B. coagulans for three weeks in daily water) and control (tap water without probiotics) groups. The total aerobic and anaerobic microorganisms, lactic acid bacteria (LAB), coliforms and spores were weekly counted in the fecal samples. Additionally, the water and feed consumption, the weight gain and Feed Conversion Ratio (FCR) were calculated for each week. RESULTS: The probiotics significantly increased the total aerobic, LAB and spore counts and caused significant reduction in the anaerobe and coliform counts. Following three weeks of probiotic administration, the number of anaerobic bacteria, and coliforms were reduced by up to 0.7 and 1.18 log and the number of aerobic bacteria, LAB and spores were increased by 1.29, 1.15 and 7.2 log respectively. Also, the results showed the feed consumption reduction, weight gain and FCR enhancement in the probiotic group (p < 0.05). CONCLUSION: Supplementation the spores of B. subtilis and B. coagulans improved the growth performance and was beneficial to the intestinal microbiota in rats.

Evidence of heat-resistant microorganisms with a special emphasis on filamentous Actinomycetes in hyper-arid soils of Gandom Beryan area, Lut Desert, Iran.

BACKGROUND AND OBJECTIVES: In the present study, the Lut Desert, Iran was chosen as one of the hottest places in the world (with the recorded temperature of 70.7°C during 2003-2009) to find out whether any heat-resistant microorganisms were present in the soil. MATERIALS AND METHODS: The samples were collected from surface and depth of three identified places of Gandom Beryan in the Lut Desert. Chemical analysis and enumeration of the total bacteria, yeasts and molds were performed. Four selective culture media were employed to isolate the filamentous actinomycetes. The suspected colonies were further confirmed using PCR assay. Then the culture cell-free-supernatants (CFS) of isolates were used to investigate their antimicrobial activity against Staphylococcus aureus, Bacillus cereus, Salmonella Typhimurium and Escherichia coli. RESULTS: Chemical analysis of the samples included moisture (0.2-0.9%), ash (85-91%), organic materials (8.3-14.4%), pH (7.59-9.40) and electrical conductivity (380-2000 µS/cm). The number of isolated bacteria and molds varied from 0-20 to 0-40 CFU/g, respectively. Number of Actinomycetes isolated from the soil samples were between 0-12.2 CFU/g. Nine isolated colonies were identified as filamentous Actinomycetes. To determine the possibility of antimicrobial peptides, the CFS (cell-free supernatant) was firstly neutralized by NaOH and catalase. The results showed that none of the CFS of the isolates was effective against E. coli, S. Typhimurium and S. aureus, while the maximum inhibitory effect was investigated on B. cereus, which was 33.1%±1.19% (mean ± SD). CONCLUSION: The results of the current study imply the presence of rare heat-resistant microorganisms in the soil of Gandom Beryan which may be further used to find out more about the function of natural bioactive compounds. Actinomycetes, as extremophile microorganisms, have shown the greatest genomic and metabolic diversity, as such the discovery of the novel Actinomycetes as a source of secondary metabolites is essential.