The essential oil (EO) composition of leaves of Campomanesia aurea was analyzed by GC-MS. The plant was collected in April (EOA) and October (EOO) in São Francisco de Assis/RS. The essential oils were obtained by hydrodistillation in a modified Clevenger apparatus. The yields were 4.44% in April, and 6.15%, in October. Thirty-one compounds were identified in EOA, accounting for 96.87% of the total, and twenty-eight compounds were identified in EOO, accounting for 99.46% of the total. For EOA, the major identified monoterpene was p-cymene (8.33%) and the major identified sesquiterpene was α-cadinol (10.72%), while regarding EOO the major identified monoterpene was repeatedly Terpinolene (3.43%), whereas the major identified sesquiterpene was α-cadinol (12.79%). The antibacterial activity of the essential oil was evaluated against the three Listeria monocytogenes from the American Type Culture Collection (strains ATCC 7644, 19114 and 13932). The essential oil showed a MIC of 10 mg/mL against the strains ATCC 7644 and 19114, with bacteriostatic effect of 20 mg/mL and a MIC of 20 mg/mL for ATCC 13932. Regarding the antibiofilm activity, o EOO showed the best results with an inhibition of 90% in the sessile growth with an applied concentration of 4.0 mg/mL.

The insertion of antibiotics in water resources results from anthropogenic sources; however, at residual concentrations, they characterize potential risks to the ecosystem, such as the emergence of multi-resistant bacteria. It is necessary to develop technologies to provide sustainable solutions for low- and middle-income countries. Thus, the present study aims to evaluate the ability to remove the antibiotic ciprofloxacin (CPX) with a biosorbent produced with pecan shells (PSB). The PSB structure was determined by scanning electron microscopy and spectroscopy in the infrared region by Fourier Transform. For adsorption assays, solutions of 10 mg L⁻¹ of CPX were used. The results show that the process reaches equilibrium at 240 min, and follows the pseudo-second order model kinetic and the Freundlich equilibrium model. The increase in temperature and the pH variation of the solution strongly influence the process. In general, the adsorption of CPX using PS is a potential method for treating water and contaminated effluents, as well as being a low-cost method; this is because it uses a byproduct from the agricultural industry that results in a reduction of approximately 60% of the antibiotic load contained in the liquid effluent.