Bioactive Substance Analysis Of Pomegranate Peel Extracts And Its Application In Storage Of Fresh Milk

Pomegranate is produced by Middle Eastern and Mediterranean region withabundant nutrients. It showed multiple bioactivities with enriched polyphenols,especially in the peel. Pomegranate peel extract (PPE)s produced from China,Yemen and Tunisia were used to determine the bioactive substances content andantimicrobial activity by agar disc diffusion method. Effect of PPE on retainingquality of fresh milk was also detected.PPEs from different regions showed difference bioactive substance contents.There were big amount of total phenols, flavonoids, polysaccharides and tanninsand little amount of protein and anthocyanin in PPEs in which China PPE showedhighest contents of total phenols, flavonoids, polysaccharide and anthocyanin withvalues of26.17GAE/100g dry base,5.24g/100g dry base and0.75g/100g dry baserespectively, Tunisa PPEs showed the highest contents of protein and tannins withvalues of0.59g/100g dry base and69.53g/100g dry base respectively.Listeria monocytogens, Staphylococcus aureus, Escherichia coli andsalmonella were selected as indicator bacteria to test antimicrobial activity of PPEs.China and Yemen PPEs were used for further research for their excellent activity.Yemen PPE showed best antimicrobial activity on Listeria monocytogens withinhibit zone of22.7mm, whereas China PPE showed best activity onStaphylococcus aureus, Escherichia coli and salmonella with inhibit zones of20.9mm,17.85mm and14.75mm respectively. China PPE could inhibit bacteriagrowth, keep initial acidity and avoid unpleasant odors during fresh milk storage.