Vibrio spp. from Macrobrachium amazonicum prawn farming are inhibited by Moringa oleifera extracts

Area of Science:

• Pharmacology
• Microbiology
• Natural Product Chemistry

Background:

• Aquaculture, particularly prawn farming, faces significant challenges from bacterial infections, especially Vibrio species.
• Vibrio species, including Vibrio cholerae, Vibrio vulnificus, and Vibrio mimicus, are known pathogens affecting aquatic organisms and human health.
• The increasing prevalence of antibiotic resistance necessitates the exploration of alternative antimicrobial agents, such as those derived from natural sources.

Purpose of the Study:

• To evaluate the in vitro antimicrobial activity of various Moringa oleifera (M. oleifera) plant part extracts against pathogenic Vibrio species.
• To determine the efficacy of M. oleifera extracts sourced from stem, leaves, flowers, pods, and seeds against Vibrio spp. isolated from hatchery water and the prawn Macrobrachium amazonicum.

Main Methods:

• Ethanol extracts of M. oleifera stem, leaves, pods, and seeds, along with a chloroform extract of flowers, were prepared.
• The antimicrobial activity was tested against Vibrio cholerae (non-O1/non-O139), Vibrio vulnificus, Vibrio mimicus, and Escherichia coli (quality control).
• Minimum Inhibitory Concentration (MIC) was determined using the broth microdilution method.

Main Results:

• The ethanol extract of M. oleifera pods demonstrated significant antimicrobial activity, inhibiting three Vibrio cholerae strains, Vibrio vulnificus, Vibrio mimicus, and E. coli (MIC range: 0.312–5.000 mg/mL).
• The chloroform extract of M. oleifera flowers was effective against all tested Vibrio cholerae strains and E. coli (MIC range: 0.625–1.250 mg/mL).
• Ethanol extracts from M. oleifera stem and seeds exhibited limited effectiveness in inhibiting bacterial growth.

Conclusions:

• Moringa oleifera extracts from pods, flowers, and leaves possess notable antimicrobial potential against harmful Vibrio species.
• These findings suggest that M. oleifera could serve as a source for natural antimicrobial agents in aquaculture.
• Further research is recommended to isolate and identify the specific bioactive compounds responsible for the observed antimicrobial effects.