The influence of dietary Motore™ supplement on antioxidant status to Aeromonas hydrophila infection in Rhamdia quelen.

This study points to evaluate the effects of pre-treatment with standardized dry extract of Curcuma longa (Motore™) added to the diet (0; 250; 500; and 750 mg/kg) on oxidative stress parameters, longevity, and therapeutic success in Rhamdia quelen experimentally infected with Aeromonas hydrophila (MF 372510). After treatment, the liver and kidney were collected to determine non-enzymatic oxidative parameters such as the formation of thiobarbituric acid reactive substances (TBARS), non-protein thiols (NPSH), and quantification of reactive oxygen species (ROS) levels. Also, two enzymatic antioxidant parameters were evaluated: superoxide dismutase (SOD) and catalase (CAT) activities. The results showed an increase of ROS and TBARS levels, a depletion in NPSH, and a decrease of SOD and CAT activities in infected fish compared to control. The highest Motore™ dose minimized the deleterious effect of A. hydrophila infection improving longevity, oxidative status, and survival rate. The addition of 750 mg Motore™/kg feed is recommended for silver catfish in fish farming. Serious economic losses in Rhamdia quelen culture caused by Aeromonas hydrophila infections can be prevented by the addition of Motore™ to the diet.

Antimicrobial Activity and Modulatory Effect of Essential Oil from the Leaf of Rhaphiodon echinus (Nees & Mart) Schauer on Some Antimicrobial Drugs.

BACKGROUND: Rhaphiodon echinus is a weed plant used in the Brazilian folk medicinal for the treatment of infectious diseases. In this study, the essential oil of R. echinus leaf was investigated for its antimicrobial properties. METHODS: The chemical constituents of the essential oil were characterized by GC-MS. The antimicrobial properties were determined by studying by the microdilution method the effect of the oil alone, and in combination with antifungal or antibiotic drugs against the fungi Candida albicans, Candida krusei and Candida tropicalis and the microbes Escherichia coli, Staphylococcus aureus and Pseudomonas. In addition, the iron (II) chelation potential of the oil was determined. RESULTS: The results showed the presence of ß-caryophyllene and bicyclogermacrene in major compounds, and revealed a low antifungal and antibacterial activity of the essential oil, but a strong modulatory effect on antimicrobial drugs when associated with the oil. The essential oil showed iron (II) chelation activity. CONCLUSIONS: The GC-MS characterization revealed the presence of monoterpenes and sesquiterpenes in the essential oil and metal chelation potential, which may be responsible in part for the modulatory effect of the oil. These findings suggest that essential oil of R. echinus is a natural product capable of enhancing the antibacterial and antifungal activity of antimicrobial drugs.