Exploring the potential of melittin peptide: Expression, purification, anti-pathogenic properties, and promising applications as a bio-preservative for beef slices

Abstract

Melittin peptide is a short cationic linear peptide derived from honey bee venom with 26 amino acids, demonstrates potential in controlling and eliminating pathogens. In this study, the genetic sequence of melittin was inserted into the pcDNA3.1+ plasmid and expressed in HEK-293 cells with a His-tag. Purification was done through affinity chromatography and a nickel column. In this study, the antimicrobial effect of melittin in beef sirloin was first investigated, and the minimum inhibitory concentration (MIC) was determined. Then, the effect of combining it with nanochitosan (n-CH) coating, melittin (0.1% and 0.2%v/v), and nanochitosan alone on the physicochemical, microbiological, and sensory properties of beef was examined over a 9-day at 4 °C. At the end of the storage period, the coated samples effectively prevented an increase in pH (5.75 ± 0.06) and showed a significant decrease in the peroxide value (PV) (4.50 ± 0.07). The most favorable result was observed when using the n-CH+0.2%M, which led to malondialdehyde level of 0.44 ± 0.0.05 mg/kg in the amount of thiobarbituric acid reactant. Additionally, the total volatile base nitrogen content in the treatment involving 0.2%M and n-CH+0.2% and 0.1%M was deemed acceptable. Although the total viable count (TVC) of microorganisms in samples covered with melittin increased over time (7.88 ± 0.12 CFU/g), the microbial growth rate in these samples was lower than the control sample (12.10 ± 0.13 CFU/g). Therefore, the use of nanochitosan based edible coatings in combination with melittin in meat packaging reduces microbial population and increases its shelf life.