The anti-biofilm effect of extracellular vesicles extracted from Holothuria Parva tissue on Staphylococcus aureus

BACKGROUND AND OBJECTIVESStaphylococcus aureus is a gram-positive bacterium that causes a wide range of clinical diseases. Infections caused by this pathogen are common in both community-acquired and hospital-acquired environments. Resistance to antibiotics has become very common in this bacterium, and in the past years, it has undergone significant . In general, biofilm formation has been challenging in the field of medicine because it interferes with ongoing medications and is associated with various diseases. Biofilms increase antibiotic resistance in the way that the dense extracellular matrix and the outer layer of the cell protect the entire biofilm community. Various anti-biofilm compounds have been used by researchers to inhibit and disturb the biofilm structure. The marine environment is an exceptional reservoir of natural products, many of which have structural properties not found in terrestrial natural products. The sea cucumber is a valuable aquatic organism that has many uses in the food, pharmaceutical and medical industries. It is well known that sea cucumbers have beneficial effects on human health and can be used for medicinal purposes. In this study, Holothuria Parva extracellular vesicles were used as one of the anti-biofilm substances.MATERIALS AND METHODSH. Parva sea cucumbers were collected from the Persian Gulf, coasts of Bushehr province. The extracellular vesicles were extracted from their tissue. Cultivation and recovery of Staphylococcus aureus ATCC ۶۵۳۸ was performed on BHI agar. Kirby-Bauer disk diffusion susceptibility test and broth microdilution assay (MIC) of sea cucumber extracellular vesicles was used for antibacterial activity. Also, the effect of sea cucumber extracellular vesicles on S. aureus ATCC ۶۵۳۸ biofilm with Minimum biofilm inhibitory concentration (MBIC) was investigated by crystal violet biofilm assay method. Different concentrations of extracellular vesicles (۰.۱۵, ۰.۳۱, ۰.۶۲, ۱.۲۵, ۲.۵, ۵ mg/ml) were tested on the bacterium.RESULTS AND DISCUSSIONThe results showed that H. Parva extracellular vesicles had no antibacterial effect on S. aureus ATCC ۶۵۳۸ and finally, anti-biofilm effect was not seen.CONCLUSIONIt is hoped that the anti-biofilm effect of extracellular vesicles will be investigated by a researcher on the other bacteria in future studies.