INVESTIGATION OF THE PRESENCE OF BIOACTIVE PEPTIDES IN TARKHINEH AND THEIR ANTIBACTERIAL ACTIVITY AGAINST FOOD BORNE PATHOGENS

Background and Aim:Tarkhineh is a traditional Iranian fermented product produced from a mixture of doogh and wheat grout. The purposes of the present study were investigation of the presence of bioactive peptides in Tarkhineh and their antibacterial activity against Staphylococcus aureus and E. coli.Methods:Tarkhineh were made in laboratory scale and their aqueous extract were prepared by maceration in phosphate buffer. Protein content of these extracts measured by Bradford method and then these extracts were filtered through filters with nominal molecular weight exclusion lower than 5000 and 10000Da. These filtrates were used as source of bioactive peptides.Results:The protein content of extracts was 1.52 ± 6 mg/ml. The results of the antibacterial activity of fractions indicated that none of the extracts didn t have any antibacterial activity against E. coli (p > 0.05), but 5000 Da extract fraction could significantly (p < 0.05) inhibit the growth of Staphylococcus aureus in comparison with unfiltered extract and 10000Da fraction. In addition results showed higher antibacterial activity against Staphylococcus aureus for unfiltered extract than 10000Da fraction, also this different was not statistically significant (p > 0.05).Conclusion:According to these results it was concluded that Tarkhineh can have bioactive peptides with antibacterial activity against gram positive pathogenic bacteria.

Keywords:

bioactive peptides , Tarkhineh , antibacterial activity , food borne pathogens