Antibacterial activity of constituents from Mangosteen (Garcinia mangostana) fruit pericarp against several channel catfish pathogens

Authors: Meepagala, Kumudini; Schrader, Kevin

Submitted to: Journal of Aquatic Animal Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/21/2018
Publication Date: 9/21/2018
Publication URL: https://handle.nal.usda.gov/10113/6473324
Citation: Meepagala, K.M., Schrader, K.K. Antibacterial activity of constituents from Mangosteen Garcinia mangostana fruit pericarp against several channel catfish pathogens. Journal of Aquatic Animal Health. 2018;30:179-184. https://doi.org/10.1002/aah.10021.
DOI: https://doi.org/10.1002/aah.10021

Interpretive Summary: Catfish production is impaired by diseases caused by bacteria and as a result the farmers lose profits. Catfish farmers typically depend on commercial antibiotics and other chemicals to prevent the economic damage from these diseases. Environmentally friendly, cost effective and safe antibiotics will tremendously help the catfish aquaculture industry. As part of our ongoing efforts in search of such compounds, we have isolated and identified compounds from mangosteen fruit peel that are effective against a bacteria that causes one type of these diseases.

Technical Abstract: Bacterial diseases cause major economic losses to the producers of channel catfish (Ictalurus punctatus) in the southeastern US. Enteric septicemia in catfish (ESC), caused by the gram negative bacterium Edwardsiella ictaluri, and columnaris disease, caused by the gram-negative rod-shaped bacterium Flavobacterium columnare, are the two most common diseases which occur in pond-raised channel catfish. Streptococcosis is another less common bacterial disease in catfish and is caused by the gram-positive coccus Streptococcus iniae. Catfish farmers typically rely on commercial antibiotics and other chemicals to prevent the economic damage from these diseases. Environmentally benign and efficacious alternatives to the currently used antibiotics and chemicals will tremendously help the catfish aquaculture industry. As part of our ongoing efforts in search of such novel compounds, we investigated ethyl acetate and methanol extracts of mangosteen (Garcinia mangostana) fruit pericarp via bioassay-guided fractionation. y-Mangostin was isolated and identified as the most promising active metabolite against the bacterium Flavobacterium columnare. The major xanthone a-mangostin in the fruit pericarp of G. mangostana was found to be 10-fold less active than y-mangostin when MIC (minimum inhibitory concentration) values were compared.