Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 5 1-2 2016 12 31 43 46 EN Reza Naghiha Department of Animal Sciences, Faculty of Agriculture, Yasouj University, Yasouj, Iran. Mokhtar Khajavi Department of Animal Sciences, Faculty of Agriculture, Yasouj University, Yasouj, Iran. Mohammad Reza Bahreini Department of Animal Sciences, Faculty of Agriculture, Yasouj University, Yasouj, Iran. Ali Naghi Keshtkaran Department of Animal Sciences, Faculty of Agriculture, Yasouj University, Yasouj, Iran. 2016 12 31 2016 12 31 Background:    Due to excessive consumption of synthetic drugs, drug resistance rate of pathogenic bacteria is increasing and there is an ever-increasing need to find new safe compounds to tackle this problem. This study was conducted to investigate the consequences of chavill extract on the growth and viability of gastrointestinal pathogenic bacterium and probiotics bacteria.  Methods:    The experiment contained three levels of the chavill extract concentrations (0, 1 and 3%) which were added to the milk free fat in accompany with three probiotic bacteria (Lactobacillus acidophilus, Lactobacillus casei and lactobacillus plantaram) and a pathogenic gastrointestinal bacterium (Salmonella typhimurium). Bacterial inoculums (1×107 CFU/ml) with different concentrations of chavill extract were added to skimmed milk medium and bacteria growth were enumerated.  Results:  The concentration of 1% chavill extract significantly increased the total count of probiotic bacteria compared to the control group, while the number of pathogenic bacteria was decreased. At 3% chavill extract the growth of Lactobacillus acidophilus and Lactobacillus plantaram were increased. On the other hand, it prevented the growth of Salmonella typhimurium  Conclusion:   Chavill extracts would play as an alternative to antibiotics in pharmacological studies to decreases harmful bacteria and increase probiotic bacteria. https://jmb.tums.ac.ir/index.php/jmb/article/view/230 https://jmb.tums.ac.ir/index.php/jmb/article/download/230/164