Medicinal plant-product encapsulated with herb-hydrogel for ammonia removal and stress alleviation in semi-biofloc system containing aquaponics water cultured with Pangasianodon hypophthalmus

Abstract

The study investigates the use of microencapsulated product of Indian gooseberry (Phyllanthus emblica) developed using hydrogel derived from isabgol (Plantago ovata) for ammonia removal in aquaponics water and the growth performance of Pangasianodon hypophthalmus for a 45-day period. The study consists of a control (C) and two treatments: T1 (isabgol) and T2 (isabgol+Indian gooseberry). Ammonia was spiked weekly at varying concentrations. T2 showed significantly highest (p < 0.05) ammonia removal in all the different spiking dosages, followed by T1. Ammonia was eliminated more rapidly in the 4th week. T2 removed 83.24 ± 0.37 % of ammonia in 36 h and 95.27 ± 0.59 % in 48 h. The decline in pH levels brought on by the nitrification process is connected with less ammonia removal in the 5th week. The fish growth indices (final total biomass, net weight gain, specific growth rate) and feed conversion ratio were significantly (p < 0.05) improved in treatment groups, with T2 exhibiting superior performance. The hematological and serum biochemical analyses indicated reduced stress in treatment groups compared to the control. The characterization of isabgol and gooseberry also revealed their potential as bioactive carriers. LC-MS analysis confirmed the presence of oxy-chromen-4-one, 4-indolecarbaldehyde, kaempferol, and apigenin in isabgol. Phenolic acid, flavonoids, essential amino acids, and vitamins were found in Indian gooseberry. The study revealed that the developed product has the potential to decontaminate high ammonia levels, mitigate stress, and improve the growth performance of P hypophthalmus, which can be attributed to the controlled release and immunostimulating effect of microencapsulated Indian gooseberry product coupled with semi-biofloc formation facilitated by hydrogel derived from isabgol.