Objective: To investigate the isolation of enterobacteria associated with Macrobrachium amazonicum (M. amazonicum) farming and evaluate the in vitro antimicrobial susceptibility of Vibrio strains. Methods: Strains were isolated from female M. amazonicum prawns and environmental and hatchery water. Biochemical assays were used to identify bacterial genera and those belonging to the genus Vibrio were submitted to further analyses for species identification, through Vitek 2 automated system and serotyping. Susceptibility test was performed according to Clinical Laboratory Standards Institute. Results: The following genera of enterobacteria were recovered: Enterobacter (n = 11), Citrobacter (n = 10), Proteus (n = 2), Serratia (n = 2), Kluyvera (n = 2), Providencia (n = 2), Cedecea (n = 1), Escherichia (n = 1), Edwardsiella (n = 1) and Buttiauxella (n = 1). As for Vibrio, three species were identified: Vibrio cholerae non-O1/non-O139 (n = 4), Vibrio vulnificus (V. vulnificus) (n = 1) and Vibrio mimicus (n = 1). Vibrio spp. showed minimum inhibitory concentrations values within the susceptibility range established by Clinical Laboratory Standards Institute for almost all antibiotics, except for V. vulnificus, which presented intermediate profile to ampicillin. Conclusions: Enterobacteria do not seem to be the most important pathogens associated with M. amazonicum farming, whereas the recovery of Vibrio spp. from larviculture, with emphasis on Vibrio cholerae and V. vulnificus, deserves special attention due to their role as potentially zoonotic aquaculture-associated pathogens. Furthermore, the intermediate susceptibility of V. vulnificus to ampicillin reflects the importance of monitoring drug use in prawn farming.

Moringa oleifera Lam (Moringaceae) is a plant with high nutritional and medicinal value. Native to India, it is now widely distributed throughout tropical and subtropical regions of the world. Its different parts are sources of proteins, vitamins and minerals and present different pharmacological and biotechnological potential. Moreover, M. oleifera seeds are widely used in water and effluent treatment, for their coagulation, flocculation and sedimentation properties, their ability of improving water quality, by reducing organic matter and microbial load, with special applicability in intensive animal production systems, such as aquaculture. In addition, due to its high nutritional value and several medicinal properties, this tree may act as a nutritional and medical alternative for socially neglected populations. In this context, this review gathers information on M. oleifera, emphasizing its chemical constituents, nutritional, pharmacological and antimicrobial properties, applications in the treatment of water effluents, and ecological and social aspects.

Objective: To investigate the in vitro antimicrobial potential of extracts of stem, leaves, flowers, pods and seeds of Moringa oleifera (M. oleifera) against Vibrio spp. from hatchery water and the prawn Macrobrachium amazonicum. Methods: The ethanol extracts of stem, leaves, pods and seeds and chloroform extract of flowers of M. oleifera were tested against Vibrio cholerae (V. cholerae) serogroups non-O1/non-O139 (n = 4), Vibrio vulnificus (n = 1) and Vibrio mimicus (n = 1). Escherichia coli (E. coli) (ATCC® 25922) was used as quality control. Vibrio species were obtained from Macrobrachium amazonicum prawns and from hatchery water from prawn farming. The Minimum Inhibitory Concentration (MIC) was determined by broth microdilution method. Results: The best result was obtained with the ethanol extract of pods, which inhibited three strains of the V. cholerae, Vibrio vulnificus, Vibrio mimicus and E. coli (MIC range 0.312-5.000 mg/mL). The chloroform extract of flowers was effective against all V. cholerae strains and E. coli (MIC range 0.625-1.250 mg/mL). However, the ethanol extracts of stem and seeds showed low effectiveness in inhibiting the bacterial growth. Conclusions: The extracts of pods, flowers and leaves of M. oleifera have potential for the control of Vibrio spp. Further studies are necessary to isolate the bioactive compounds responsible for this antimicrobial activity.