Abstract Olive (Olea europaea L.) leaves are rich in phenolic substances, which exert important
antioxidant and antibacterial effects. In this study, the effect of olive leaves extract (OLE) on the
microbial load of raw peeled undeveined (PUD) shrimp (Penaeus semisulcatus) was evaluated.
Alcoholic OLE extracts were prepared at 0.5%, 1% and 2% (w/v) concentrations. Raw PUD
shrimp samples were immersed in the treatment solutions for 3 h at 4 C and samples were taken
for determination of total viable count (TVC) and total coliforms count (TCC). OLE at concentration
of 1% (w/v) significantly (p< 0.01) reduced the count of the aerobic and coliforms bacteria at
least 1 log cycle CFU/g in reference to the non-treated control group. Such antimicrobial activity
was concentration dependent and usage of 2% OLE had the most beneficial effect in controlling
microbial load in PUD shrimp stored at 4 C. This study demonstrates the potential use of OLE
formulations to improve the microbial quality of PUD shrimp and OLE might be useful to the
seafood industry as a natural preservative.
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