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Background&Objective: Probiotics have been defined as live microorganisms that confer a health effect on the host when consumed in adequate amounts.Lactic bacteria play an important role in production and maintenance of the fermented and probiotic products.The aim of this study was to determine the efficacy of lactic bacteria, which isolated from yoghurt against Gastrointestinal pathogenic microorganisms in the Golestan province in North of Iran. Materials&Methods: In this descriptive study we used 96 strains which belong to 12 species of Lactobacillus and 5 species of Lactococcus ,that isolated from home made yoghurt, and their antimicrobial effect on 7 species of important intestinal pathogenic microorganisms were examined.After growing the Lactic bacteria in broth media centrifuged and filtred the suspension and used the supernatant for study.The effect of supernatant against intestinal pathogenic microorganisms were assessed by Disc diffusion and pour in well method and each test were repeated 3 times and mean inhibition zone were recorded. Results: Lactobacillus casei and Lactococcus lactis showed better effect than other strains.The maximum light zone diameter was 18 milimeter. Maximum and minimum inhibitiry effect has seen in Yersinia enterocolitica and Bacillus cereus. Conclusion: Both Lactobacillus and Lactococcus strains had a proper inhibitory effect on the intestinal pathogenic bacteria but Lactobacillus strains that present in yoghurt showed better effect. This inhibitory effect was more obvious on the Yersinia enterocolitica.

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Antibiotics usage in domestic animals, as antibiotic growth promoters (AGPs) was considered from middle of 1950 onwards. Antibiotic feed additives as growth promoters have long been supplemented to animal food in very low amounts (5 to 20 ppm) to stabilize the intestinal microbial flora, improve the general performances, and prevent some specific intestinal pathogens. The widespread use of antibiotics as AGPs is playing a significant role in the emergence of resistant bacteria. The resistant bacteria in animals due to antibiotic exposure can be transmitted to human through the consumption of their products, from close or direct contact with animals, or through the environment and consequently, the increased concern about the potential for antibiotic resistant bacteria was led the European ::::union:::: and the United States regulations banning the use of AGPs in animal food since 2006. Various studies always look for a suitable replacement antibiotics to substitute to preserve the valuable role of these compounds. Extensive efforts on these alternatives have been started in last decades and some of these alternatives such as probiotics, prebiotics, synbiotics, ionophores, acidifier, organic acids, medicinal herbs and phytogenic can be pointed out. Hence, the aim of this review is to evaluate the antibiotic replacement strategy particularly medicinal herbs and their mechanisms as new growth and health promoters.

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Background and Objective: Probiotics are beneficial organisms therapeutic within microbial flora. Shigella, Escherichia coli and Salmonella are the most common cause of intestinal infectious diseases that lead to morbidity and mortality in infant and children worldwide. The aim of this study was to evaluate anti-microbial activity of Lactobacillus acidophillus and Lactobacillus ruteri against entero-pathoges by in vitro and in vivo methods. Methods: In this experimental study, the therapeutic effect of the lactobacillus acidophilus ATCC 4356 and ruteri ATCC 23272 against Shigella sonnei ATCC 9290, Escherichia coli ATCC 25922 and Salmonella enterica BAA-708 were evaluated by in vitro (spot agar) and in vivo (BALB/c mice) methods. Weight improvment and survival rate in mice were recorded. Results: Lactobacillus acidophillus and ruteri had protective and therapeutic effect against diarrhea caused by pathogenic bacteria. Probiotics reduced the weight, colonization of pathogens and increased the survival rate of animals (P<0.05). Conclusion: Lactobacillus acidophillus and ruteri has anti-microbial activity and their consumption can be effective in the prevention and also the treatment of intestinal disease.

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Background and Objective: Probiotc bacteria have benefical effect on consumer health. This study was done to investigate the antimicrobial effect of several probiotic in combinations with different prebiotics against food patoghenic bacteria including Staphylococcus aureus and Listeria monocytogenes.

Methods: In this descriptive - analytical study, probiotics including Lactobacillus plantarum, L. acidophilus, L. fermntum, L. casei and L. rhamnosus with prebiotics (1%) including raffinose, lactulose, inulin and trehalose were cultured in MRS broth for 24 hours at 30ºC in anaerobic conditions. Antimicrobial property of them was determined with well diffusion plate's method.

Results: Probiotics in the presence of prebiotics indicated the higher antimicrobial effect compared to probiotics alone (P<0.05). The application of prebiotics such as L. casei with raffinose showed higher antimicrobial property against Listeria monocytogenes than the free prebiotics consumption. The diameter of inhibitory growth zone in the presence of raffinose as a prebiotics was 14.66 mm and its absence reduced to 11.75 mm.

Conclusion: Antimicrobial effect of probiotics in combination with prebiotics against Staphylococcus aureus and Listeria monocytogenes was higher than probiotics consumption alone.

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Background and Objective: Parkinson's disease is a neurological disorder caused by the loss of dopaminergic neurons in pars compacta of substantial nigra. The most important symptoms of this disease include slow motion, lack of movement, tremor and imbalance. This study was done to determine the effect of probiotic Lactobacillus paracasei on motor disorders caused by injection of 6-hydroxy dopamine in Parkinson's model in male rats.
Methods: In this experimental study, 48 male rats were randomly allocated into six groups. To create an animal model of Parkinson's disease, a black body component in male rats was injected 6-hydroxy dopamine (6-OHDA) (0.5 mg/kg) unilaterally by stereotaxic apparatus. After 3 weeks of recovery, to evaluation of degradation rate, animals were received apomorphine, intraperitoneally. In the first experiment, rats were randomly divided into Sham and Parkinson's (injured) groups, the Sham group were received only water and food, and the injured group received 6-hydroxy-dopamine. In the second experiment, male rats were divided into 4 groups of 8 rats, each of the 4 groups was injected 6-hydroxy-dopamine and 21 days later, they were tested for assay of apomorphine. The results were recorded, then for 28 days, the first group was taken as control. The second group of saline, the third group of milk, the fourth group of milk and probiotic were gavaged. At the end of day 28, once again, each group was subjected to rotation of apomorphine test and the rotations were recorded.
Results: The behavioral analysis of saline, milk, milk plus probiotics were indicated that the group receiving probiotic Lactobacillus paracasei plus milk was significantly less apomorphine rotation test than the saline group (P<0.05).
Conclusion: It seems that probiotic Lactobacillus paracasei can reduces Parkinson’s disease symptoms.