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Pharmaceuticals are often found in the water environment and are not completely degraded by conventional treatment processes. There are some techniques, such as advanced oxidative processes (AOPs), which can promote, in addition to the total removal of contaminants, their mineralization, transforming them into CO2 and water. Thus, the objective of this work was to evaluate the mineralization capacity of the emerging pollutants caffeine and ampicillin, present in a real aqueous matrix, through ozonation. Factorial planning was carried out by Central Composite Design (CCD) under the Response Surface Methodology (RSM). Water samples were collected from Arroio Dilúvio, a river that cuts through the city of Porto Alegre (RS -- Brazil), which receives domestic, hospital, and industrial effluents in nature. The experiments were conducted from the analysis of the influence of pH, time, and ozone flow rate variables. The ozonation system consisted of an oxygen concentrator, an ozone generator, and a gas washer bottle. With removals of caffeine and ampicillin around 100 and 99.7%, respectively, a mineralization of 30.8% was also obtained under conditions of pH 8, with an applied ozone dosage of 830 mg.L-1. In this process, the gas phase concentration was at 16.7 mg.L-1 when applied to 200 mL sample for 10 minutes and ozone flow rate of 1 L.min-1. A linear relationship was observed between the real and predicted values, and it has been shown that the relationship of the residual plot confirmed a sufficient approximation of the method for the optimization process. Finally, the desirability function showed adequate operating conditions for the mineralization of compounds by ozonation. Therefore, it is considered that this technique is effective for the mineralization of the pharmaceuticals studied, and can be applied as a way of treating a contaminated real matrix. [ABSTRACT FROM AUTHOR]

Different bioproducts can be obtained by changing operative condition of biotechnological process, and this bioprocess aspect is a significant approach to be adopted on industrial scale leading to the creation of new natural aroma. Thus, this study aimed to investigate the culture conditions and optimization of the biotransformation of limonene into limonene-1,2-diol using Pestalotiopsis mangiferae LaBMicrA-505 obtained from the Brazilian Amazon. The study started with the investigation of the establishment of culture, followed by optimization of the conditions for biotransformation of R-(+)-limonene to limonene-1,2-diol, using shake flasks. The fresh biomass of P. mangiferae LaBMicrA-505 obtained in liquid media supplemented with yeast-malt extract under with 72 h (stationary phase) performed better diol productivity when compared to other biomasses. Finally, in the modeling of contour plots and surface responses of a central composite design, the use of 4 g l - 1 biomass, 2% of the substrate at 24 °C, 120 rpm, and pH of 6.0 could maximize the production of limonene-1,2-diol, accumulated up to 98.34 ± 1.53% after 96 h of reaction. This study contributed to identified operational condition for the R-(+)-limonene bioconversion scale-up. The endophytic fungus P. mangiferae LaBMicrA-505 proved to be a potent biocatalyst to biotechnologically produce limonene-1,2-diol, an aroma compounds with interesting bioactive features that up to now has been manufactured by extraction from plants with long and not environmentally friendly procedures., (© 2024. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

This study proposes a simple and effective method for determination of Al, Cd, Cu, Ni, and Zn in soil samples, associating ultrasound-assisted extraction and flame atomic absorption spectrometry (FAAS). Ultrasound-assisted extraction conditions were optimized using a central composite design. This method required small volumes of HCl, HNO 3 , and HF as an extraction solvent blend to ensure effective analyte extraction. Limits of detection and quantification were determined to assess the minimum accurate concentration of the studied elements that can be detected and quantified in a soil sample. Therefore, the ultrasound-assisted extraction was concluded as a simple and straightforward pretreatment technique to determine Al, Cd, Cu, Ni, and Zn concentrations in soil samples. Eight sites of agricultural and native forest areas of the city of Ponta Grossa and Guarapuava, State of Paraná, Brazil, were evaluated for metals, and compared with the reference values for trace elements provided by the Brazilian National Environment Council. Environmental assessment of soils from those eight sites was accomplished through I geo , EF, CF, and PLI parameters, which aimed at the evaluation of agricultural sites in comparison with adjacent natural forest sites with no history of anthropogenic mobilization to determine the degree of the contribution of anthropogenic sources to metal concentrations. According to the I geo , EF, and CF parameters, all sites were classified as unpolluted to moderately polluted and none or minor enrichment due to anthropogenic activities were noticed. PLI parameter evaluated the concentration of all studied metals in soils to stipulate an order of contamination, which was concluded as site 8