Mechanistic aspect of uptake, translocation and subcellular distribution of tetracycline in Pelargonium graveolens L.

In recent years, the presence of antibiotics in soil is major concern due to its hazardous effect on human health, soil microbiota, and food crops. The phytoremediation is considered an effective method for removing antibiotics from contaminated sites. However, the effectiveness and efficiency of many plants in the removal of antibiotics are still unknown. In this study, the potential of Pelargonium graveolens L. in the removal of tetracycline (TC) from soil was investigated at three different concentrations (100 mg kg−1, 200 mg kg−1 TC, and 400 mg kg−1). The mechanism of antibiotic sequestration in the plant was also examined in a hydroponic system at three different concentrations (5 mg L−1, 10 mg L−1, and 15 mg L−1). The results demonstrated that the concentrations of TC in leaves, stems, and roots ranged from 13.57 to 21.57 mg kg−1, 0.27–0.48 mg kg−1, and 5.19–7.09 mg kg−1 in different soil treatments. The TC treatments led to a significant reduction in biomass (23.3–54.8 %), root length (42.3–69.2 %), as well as chlorophyll a (24.48–52.18 %), chlorophyll b (16.35–31.70 %), and protein content (23–42.4 %) compared to the control. Moreover, there was a notable increase in proline and SOD activity (19.54–45.72 %) in plant leaves. Hydroponic study demonstrated that more uptake of TC by symplast (1.75–10.51 mg kg−1) than in the apoplast (0.09–9.63 mg kg−1). The Michaelis-Menten kinetic suggested that a higher upward translocation capacity and greater affinity of TC in the aboveground parts of P. graveolens. The higher sequestration of TC was observed in soluble fraction of all tissues. Tetracycline accumulation and distribution suggested that P. graveolens can withstand tetracycline stress and can be used for remediation purpose for antibiotic contaminated areas. [Display omitted] • P. graveolens demonstrated a good tolerance index for tetracycline. • The symplast was the dominant pathway for uptake. • Michaelis-Menten kinetic suggested favourable upward translocation in plant. • P. graveolens displayed good potential for remediation for tetracycline. [ABSTRACT FROM AUTHOR]