Identification of low molecular weight antimicrobial peptides from Iraqi camel milk fermented with Lactobacillus plantarum

Fermented camel milk plays a significant role as a natural source of proteins in desert and semi-desert regions. In this study, fermented camel milk was investigated for antibacterial activity. The milk was pasteurized at 90 °C for 30 a minute period, cooled down to 42 °C and inculcated with Lactobacillus plantarum, and incubated at 42 °C for 24 h. The fermented milk was fractionated by RP-HPLC in order to determine the antibacterial activity, and also to identify the peptides by LC–MS/MS. The antimicrobial activity of the fractionated peptides was tested against Staphylococcus faecalis, Shigella dysenteriae, Staphylococcus aureus and E. coli. Fraction 14 demonstrated the highest antimicrobial activity, and contained 32 peptides belonging to various milk proteins. The fermented camel milk is a rich source of low molecular peptides, and is recommended to improve the overall health of consumers. The Lactobacillus plantarum selected for this study is a suitable starter culture to be used for camel milk fermentation.