Compound isolation through bioassay-guided fractionation of Tectona grandis leaf extract against Vibrio pathogens in shrimp

• Published in: International microbiology Vol. 27; no. 4; pp. 1195 - 1204
• Main Authors: Ghosh, Alokesh Kumar, Panda, Sujogya Kumar, Hu, Haibo, Schoofs, Liliane, Luyten, Walter
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-08-2024
• Subjects: Applied Microbiology; Biomedical and Life Sciences; Eukaryotic Microbiology; Life Sciences; Medical Microbiology; Microbial Ecology; Microbiology; Bioassay-guided purification; Shrimp; Active compounds; Tectona grandis; Vibrio
• ISSN: 1618-1905; 1618-1905
• DOI: 10.1007/s10123-023-00468-5

Tectona grandis
Linn, commonly known as teak, is traditionally used to treat a range of diseases, including the common cold, headaches, bronchitis, scabies, diabetes, inflammation, and others. The present study was conducted with the purpose of isolating and identifying the active compounds in
T. grandis
leaf against a panel of
Vibrio
spp., which may induce vibriosis in shrimp, using bioassay-guided purification. The antimicrobial activity was assessed using the microdilution method, followed by the brine shrimp lethality assay to determine toxicity. Following an initial screening with a number of different solvents, it was established that the acetone extract was the most effective. The acetone extract was then exposed to silica gel chromatography followed by reversed-phase HPLC and further UHPLC-orbitrap-ion trap mass spectrometry to identify the active compounds. Three compounds called 1-hydroxy-2,6,8-trimethoxy-9,10-anthraquinone, deoxyanserinone B, and khatmiamycin were identified with substantial anti-microbial action against
V. parahaemolyticus
,
V. alginolyticus
,
V. harveyi
,
V. anguillarum
, and
V. vulnificus
. The IC
50
values of the three compounds viz. 1-hydroxy-2,6,8-trimethoxy-9,10-anthraquinone, deoxyanserinone B, and khatmiamycin varied between 2 and 28, 7 and 38, and 7 and 56 μg/mL, respectively, which are as good as the standard antibiotics such as amoxicillin and others. The in vivo toxicity test revealed that the compounds were non-toxic to shrimp. The results of the study suggest that
T. grandis
leaf can be used as a source of bioactive compounds to treat
Vibrio
species in shrimp farming.