Basil oil nanoemulsion formulation and its antimicrobial activity against fish pathogen and enhance disease resistance against Aeromonas hydrophila in cultured Nile tilapia

Abstract

Pure basil oil which has antimicrobial and immunostimulant effect in the cultured fish was formulated into nanoemulsion using homogenizer. Basil oil nanoemulsion characters, its effect as antimicrobial in vitro and its resistant against Aeromonas hydrophila were studied. The results revealed that the droplet size distribution of the basil oil nanoemulsion measured 6.419 nm in diameter with poly dispersity index (PDI) value 0.753, Zeta potential-1.01mV, pH value 5.55, the conductivity 203.5 µS/m and the viscosity 0.887 mpascal/sec. Basil oil nanoemulsion had antibacterial effect at 6µl concentration against Aeromonas hydrophila, Aeromonas veronii, Pseudomonas fluorescens and Streptococcus agalactiae while, at 3µl concentration had antifungal effect against Saprolegnia parasitica. Minimum inhibitory concentration (MIC) of this formulation of basil oil differ among the examined bacterial isolated from 3-9 µl. Basil oil nanoemulsion save for Oreochromis niloticus at 8.5% of fish body weight for 14 days and increased fish resistance. Moreover, basil oil nanoemulsion showed different effects against A. hydrophila by using ultrastructure electron microscope which were discussed in this study.

Antiparasitic and Antibacterial Functionality of Essential Oils: An Alternative Approach for Sustainable Aquaculture

“…Gulec, et al [101] [119]. It was determined that S. agalactiae had high susceptibility towards the O. Basilicum [105], M. piperita [45], C. Nardus [102], and S. Aromaticum [103] with MIC value of 9 µL/mL, 0.125 mg/mL, 0.244 µg/mL, and 0.015 µg/mL, respectively.…”

“…A strong inhibitory effect of Ocimum basilicum EO with 3 μL/mL and 9 μL/mL MIC values was reported on A. hydrophila and A. veronii , respectively [ 105 ]. Among nine different herb EOs, Conobea scoparioides and Lippia origanoides EOs had remarkable activity against A. hydrophila with the low respective MIC and MBC values of 200 μg/mL [ 106 ].…”

“…Pseudomonas fluorescens is a harmful pathogen in a variety of farmed fish. It was reported that Ocimum basilicum EO exhibited a potent inhibitory with 9 μL/mL MIC value on P. fluorescens [ 105 ]. C. Nardus [ 102 ] and S. aromaticum [ 103 ] EOs showed marked activity on Pseudomonas spp.…”

“…Among L. alba , L. sidoides , M. piperita , O. gratissimum , and Z. officinale EOs, strong inhibitory effects of L. sidoides EO was reported on Streptococcus agalactiae with 312.5 μg/mL MIC and 416.7 μg/mL MBC values [ 119 ]. It was determined that S. agalactiae had high susceptibility towards the O. Basilicum [ 105 ], M. piperita [ 45 ], C. Nardus [ 102 ], and S. Aromaticum [ 103 ] with MIC value of 9 μL/mL, 0.125 mg/mL, 0.244 μg/mL, and 0.015 μg/mL, respectively.…”

Modulation of Antioxidant Defense in Farmed Rainbow Trout (Oncorhynchus mykiss) Fed with a Diet Supplemented by the Waste Derived from the Supercritical Fluid Extraction of Basil (Ocimum basilicum)

“…Previous studies showed beneficial effects of these bioactive compounds on growth, immunity, antibacterial and antiparasitic activities in fish crops [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ]. In particular, Ocimum basilicum was effective against Streptococcus agalactiae and Pseudomonas fluorescens , pathogens of particular concern for farmed fish [ 19 ].…”