Medicinal and aromatic plants assisted bioremediation of ammonical and bacterial contaminants in aquaponics water

An experiment was conducted under laboratory conditions to examine the effect of sixteen medicinal and aromatic plants (MAPs), namely Aloe barbadensis, Cymbopogen citratus, Bacopa monnieri, Senna sigueana, Plantado ovata, Asparagus racemosses, Phylanthus emblica, Vitex negundo, Cammiphora wightii, Cymbopogon martini, Andrographis paniculate, Ocimum tenuiflorum, Gymnema sylvestre, Centella asiatica, Adhatoda vasica, and Cyamopsis tetragonoloba in the removal of total ammonia-N (TAN) from aquaponics water. The different dried and grounded MAPs were added @ 100 mgl^-1 into individual conical flasks containing 100 ml aquaponics water (spiked with 5 mgl^-1 ammonia) and placed in a shaker. The effectiveness of different MAPs in removing TAN was evaluated at 24 hrs intervals until one of the MAPs achieved a removal rate of over 80%. The study also investigated their potential activity against fish bacterial pathogens viz. Edwardsiella tarda, Escherichia coli, Vibrio parahaemolyticus, Aeromonas hydrophila, and Staphylococcus aureus using the agar well diffusion method. The study indicates a negligible removal of TAN in the first twelve hours for all the MAPs. TAN concentration significantly reduced from 24 hrs for amla-treated water followed by satavari-treated water. Within 96 hrs., amla, satavari, and jalbrahmi removed 88.13 ± 0.81%, 79.52 ± 2.27%, and 77.22 ± 0.70 of TAN respectively. Other MAPs showed little effectiveness in removing ammonia, while cluster beans and ardushi increased the ammonia level in the water. Additionally, the methanol extract of amla exhibited strong antibacterial activities against all tested pathogens especially, against E. tarda. This study suggests the potential application of a MAP-based One-Health approach for mitigating abiotic and biotic stresses in aquaculture. PRACTITIONER POINTS: Evaluated 16 different medicinal and aromatic plants (MAPs) for their ammonia removal activity from aquaponics water. Amla treated water showed the highest ammonia removal followed by Satavaari and Jalbrahmi. Cluster beans and Ardushi treated water resulted in increasing ammonia levels due to their high nitrogen contents. Methanolic extract of amla showed bactericidal activity against fish pathogens Edwardsiella tarda, E. coli, Vibrio parahaemolyticus, A. hydrophila, and S. aureus. Potential applications in developing aquaponics production system of fish with medicinal plants through nutrient cycling and water recycling.