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Wastewater generated from agricultural activities and food production is a source of environmental pollution, and its treatment is a challenging technological issue. Ozone gas (O3), and the possibility of associating it with hydrogen peroxide (H2O2), has the potential to remove persistent organic compounds in effluents. In the present work, wastewater from industrial potato processing was characterized, and its treatment with ozone combined with hydrogen peroxide was assessed. The inlet ozone concentration and the flow rate were 84.5 mg L−1 and 62.5 mL min−1, respectively. The promising conditions of temperature, pH, and H2O2/O3 proportion were determined to reduce the chemical oxygen demand, turbidity, and color, according to a central composite rotatable design. The H2O2/O3 proportions were 0.1, 0.3, 0.5, and 0.6. Additionally, the response variables were evaluated as a function of the ozone and hydrogen peroxide treatment time for up to 24 h. The conditions obtained for treating wastewater from industrial potato processing were the following: temperature = 25°C; pH = 3.0, and H2O2/O3 proportion = 0.1. For the water quality parameters adopted, the combination of ozone and hydrogen peroxide was effective at removing color and turbidity. The chemical oxygen demand, color, and turbidity reduction stabilized after 1.16 h, with cumulative applied dosages of ozone and hydrogen peroxide equal to 380 mg L−1 and 35 mg L−1, respectively. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the effectiveness of ozone in the control of fungi and the degradation of fumonisins in maize and possible effects on the chemical composition of the product. Two cultivars of hybrid maize (30F53H and AS1581 PRO) were used. Initially, the saturation process of the porous medium with ozone was studied. The incidence of Fusarium verticillioides, Penicillium spp. and Aspergillus flavus; the suitability of ozone to detoxify grains contaminated by fumonisins and possible qualitative changes in the product were evaluated. Ozone was applied at an inlet ozone concentration of 13.5 mg L−1 and flow rate of 1.0 L min−1, in five exposure periods (0, 12, 24, 36, 48 and 60 h). The estimated daily intake of FB by horses from grains subjected to ozonation was obtained. For the hybrid AS1581PRO, the estimated saturation time and concentration were equivalent to 67.34 min and 5.91 mg L−1, respectively. With regard to the hybrid 30F53H, the saturation time and concentration were 41.74 min and 8.72 mg L−1, respectively. Ozone was an effective fungicidal agent. The use of a concentration of 13.5 mg L−1 over a 24 h-treatment led to a reduction of 81.2 and 86.2% in the concentrations of fumonisin B1 and fumonisin B2, respectively. The estimated daily intake of fumonisins was reduced to 17.21 µg kg−1BW per day, corresponding to half of the acceptable daily intake for equines. Ozone did not affect the chemical composition of the grain. Ozone is effective in controlling fungi and as a detoxifying agent in maize contaminated by fumonisins. [ABSTRACT FROM AUTHOR]

Abstract The dissipation of difenoconazole and linuron using an open-field experimental approach with carrots exposed to one-, two- and fivefold the recommended dose of the pesticides was evaluated to provide safe recommendation to ensure food safety of carrots. The pesticide residue analysis was performed with solid-liquid extraction with low temperature partitioning technique (SLE/LTP) followed by gas chromatography analysis. The recovery percentages of extracts obtained from samples of carrot passed through SLE/LTP extraction and fortified with difenoconazole and linuron pesticides varied from 93.4% to 106.3% and from 95.1% to 116.6%, respectively. The limit of detection for difenoconazole was 0.02 and 0.12 mg kg−1 for linuron. The limit of quantification for difenoconazole was 0.05 and 0.36 mg kg−1 for linuron. The degradation time for fifty percent of the applied pesticide at the different doses ranged from 2.4 to 3.6 days for difenoconazole and from 7.5 to 10.5 days for linuron. At the end of the pre-harvest interval, carrots treated with fivefold the recommended dose of both pesticides were considered unfit for consumption. Despite monitoring the degradation products of the applied pesticides by gas chromatography coupled to mass spectrometer, none degradation product was identified on the carrots. Graphical abstract fx1 Highlights • The SLE/LTP-GC/ECD method was validated of pesticide quantification in carrots. • Simultaneous quantification of difenoconazole and linuron was performed. • The degradation of the pesticides in carrot followed a pseudo first-order kinetics. • Using fivefold the recommended dose of pesticides exceeded Brazilian and UE MRLs. • No degradation products of applied pesticide were found in the carrots. [ABSTRACT FROM AUTHOR]

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Insect pests may make food products and by-products unfit for human consumption. This study reports the occurrence of Lasioderma serricorne (Coleoptera: Anobiidae) in packaged seeds of black Sesamum indicum. An intact plastic pot of S. indicum seeds was purchased by a consumer in a supermarket in Divinópolis, Minas Gerais state, Brazil, in April 2014 and was kept at his home for 3 months. Two hundred adults of this insect (196 dead and 4 alive) were counted in the pot with the seeds, besides three live larvae. This insect fed on S. indicum seeds, making them unfit for consumption. L. serricorne feed on and reproduce in S. indicum seeds stored in plastic packaging. [ABSTRACT FROM AUTHOR]

Bioinsecticides are regarded as important alternatives for controlling agricultural pests. However, few studies have determined the persistence of these compounds in stored grains. This study aimed at optimizing and validating a fast and effective method for extraction and quantification of residues of safrole (the main component of Piper hispidinervum essential oil) in cowpea beans. It also sought to assess the persistence of this substance in the grains treated by contact and fumigation. The proposed method used headspace solid-phase microextraction (HS-SPME) and gas chromatography with a flame ionization detector (GC/FID). Factors such as temperature, extraction time and type of fiber were assessed to maximize the performance of the extraction technique. The performance of the method was appraised via the parameters selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy. The LOD and LOQ of safrole were 0.0057 and 0.019 μg kg−1, respectively and the determination coefficient (R2) was >0.99. The relative recovery ranged from 99.26 to 104.85, with a coefficient of variation <15%. The validated method was applied to assess the persistence of safrole residue in grains, where concentrations ranged from 1.095 to 0.052 µg kg−1 (contact) and from 2.16 to 0.12 µg kg −1 (fumigation). The levels measured up from the fifth day represented less than 1% of the initial concentration, proving that safrole have low persistence in cowpea beans, thus being safe for bioinsecticide use. Thus, this work is relevant not only for the extraction method developed, but also for the possible use of a natural insecticide in pest management in stored grains. [ABSTRACT FROM AUTHOR]

Essential oils (EOs) are widely recognized as efficient and safe alternatives for controlling pest insects in foods. However, there is a lack of studies evaluating the toxicological stability of botanical insecticides in stored grains in order to establish criteria of use and ensure your efficiency. The objective of this work was to evaluate the toxicological stability of basil essential oil (O. basilicum) and its linalool and estragole components for Sitophilus zeamais (Motschulsky) adults in corn grains by fumigation. The identification of the chemical compounds of the essential oil was performed with a gas chromatograph coupled to a mass selective detector. Mortality of insects was assessed after 24 h exposure. After storage for six (EO) and two months (linalool and estragole) under different conditions of temperature (5, 20, and 35 °C) and light (with and without exposure to light), its toxicological stability was evaluated. Studies revealed that the essential oil of O. basilicum and its main components exhibited insecticidal potential against adults of S. zeamais. For greater toxicological stability, suitable storage conditions for them include absence of light and temperatures equal to or less than 20 °C. [ABSTRACT FROM AUTHOR]

• Models were developed to estimate COD removal in anaerobic reactor treating BWW. • Models were calibrated and validated using rigorous statistical procedures. • The impeller used dispenses use of baffles and draft tubes in the reactor. • Even when operated at high loading rates, the reactor presented good performance. Biodiesel is an important source of renewable energy, whose production generates wastewater (BWW) comprised mainly of glycerol as the source of organic matter (COD). Anaerobic digestion of BWW is a promising technique for the remediation of this environmental hazard. Anaerobic biodegradation of glycerol present in BWW is influenced by parameters such as reaction time, amount of biomass inoculum and operating temperature. The objective of this work was the optimization and mathematical modeling of these parameters to maximize the performance of an anaerobic sequencing batch reactor (AnSBR) for treating BWW. The amount of biomass inoculum had the greatest influence on COD removal efficiency. Temperature and reaction time had greater influence on behavior of the parameters responsible for AnSBR buffering, including total volatile acids and total, partial, intermediate and bicarbonate alkalinities. Even when operated under loading rates above the values reported in the literature, the AnSBR presented satisfactory performance. The mathematical model generated in this work can be used for forecasting, process control and reactor scaleup. [ABSTRACT FROM AUTHOR]

Ozone (O 3 ) is a powerful oxidant and is used in water treatment, pest disinfection and the removal of pesticides, mycotoxins and other contaminants from fruits and vegetables. However, the treatment conditions should be specifically determined for all types of products for the effective and safe use of ozone. The aim of this study was to evaluate the effect of ozone applied as gas (0–5 mg L −1 ) and dissolved in water (0–10 mg L −1 ) on the quality of carrots. The exposure of carrots to ozone as gas and dissolved in water did not alter the weight loss percentage, firmness and the color of the vegetable. The O 3 treatments as gas also did not affect the pH of the carrots. However, in treatments with O 3 dissolved in water, the ozone concentrations and its interaction with temperature temporarily affected the pH of carrots. Moreover, O 3 as gas prevented the sharp increase in soluble solids during storage for five days (18 ± 2 °C, 80 ± 5% RH), thereby increasing the shelf-life of carrots. [ABSTRACT FROM AUTHOR]

[Display omitted] • Successful use of extraction and chromatographic methods to quantify fungicides. • Ozone-bubbled water at 3 mg L-1 was the most efficient treatment to remove fungicide residues. • Ozone-bubble water at lower concentration (1 mg L-1) did not affect the quality of bell peppers. • Alkaline solutions and oxidizing were more efficient in removing fungicides in bell pepper. • The physicochemical changes of washed fruits were evaluated over 13 days of storage. Food safety problems caused by pesticide residues in vegetables have become a top issue to raise public concern. In this study, bell peppers were grown in an experimental field and sprayed with two systemic (azoxystrobin and difenoconazole) and one contact (chlorothalonil) fungicides. Ozone (ozonated water and water continuously bubble with ozone) or conventional domestic (washing with distilled water, detergent, acetic acid, sodium bicarbonate, and sodium hypochlorite solutions) procedures were investigated to identify the most effective way to remove fungicide residues in bell peppers. The residues in the fruits and the washing solutions were determined by solid–liquid extraction with a low-temperature partition (SLE/LTP) and liquid–liquid extraction with a low-temperature partition (LLE/LTP), respectively, and analyzed by gas chromatography. Water continuously bubbled with ozone a concentration of 3 mg L-1 was the most efficient treatment with removal of fungicides residues ranging from 67% to 87%. However, similar treatment at a lower concentration (1 mg L-1) did not only efficiently removed fungicide residues (between 53% and 75%) but also preserving the quality of the fruit along a storage time of 13 days. Among the conventional solutions, sodium bicarbonate at 5% showed good efficiency removing between 60% and 81% of the fungicide residues from bell peppers, affecting the color quality of the fruit. Overall, the most affected physicochemical parameters in bell peppers after the treatments were weight loss, color, and vitamin C content. [ABSTRACT FROM AUTHOR]

The efficiencies of two conventional domestic procedures (immersion in pure water and detergent solution at 0.25 and 1%) and two treatments using ozone (immersion in water with bubbling O 3 and immersion in ozonated water, both at 1 and 3 mg L−1) were evaluated for the removal of residues of the fungicides azoxystrobin, chlorothalonil and difenoconazole in tomatoes. The fungicides were sprayed on the fruits at the recommended concentration for the crop. The residues in the tomatoes and in the washing solutions were determined by extraction with low-temperature partition techniques and analysis by gas chromatography. More concentrated solutions were more effective in removing pesticide residues. The water bubbled with ozone at 3 mg L−1 was the most efficient treatment for the removal of fungicides, reaching a reduction of 70–90% of the residues. However, the treatments with the lowest concentration of ozone had lower loss of fruit mass during storage. Unlabelled Image • ESL/LTP and ELL/LTP successfully employed for pesticide quantification by GC/ECD. • Immersion in water and detergent solution removed a considerable part of the waste. • Treatments with ozone were more efficient in removing pesticide residues in tomatoes. • The use of ozone during processing and storage increases the shelf-life of the tomatoes. • In general the treatments did not change the quality of the fruits. [ABSTRACT FROM AUTHOR]

The essential oil of basil ( Ocimum basilicum ) has significant biological activity against insect pests and can be extracted through various techniques. This work aimed to optimize and validate the extraction process of the essential oil of O. basilicum submitted to different drying temperatures of the leaves and extracted by the combination of a Clevenger method and ultrasound. The biological activity of the extracted oil under different conditions was evaluated for potential control of Sitophilus zeamais . The extraction method was optimized according to the sonication time by ultrasound (0, 8, 19, 31 and 38 min) and hydrodistillation (20, 30, 45, 60 and 70 min) and drying temperature (20, 30, 45, 60 and 70 °C). The bioactivity of the essential oil was assessed against adults of S. zeamais and the effects of each variable and its interactions on the mortality of the insects were evaluated. The best yield of essential oil was obtained with the longest sonication and hydrodistillation times and the lowest drying temperature of leaves. Higher toxicity of the essential oil against S. zeamais was obtained by the use of ultrasound for its extraction. The identification and the relative percentage of the compounds of the essential oil were performed with a gas chromatograph coupled to a mass selective detector. The performance of the method was assessed by studying selectivity, linearity, limits of detection (LOD) and quantification (LOQ), precision and accuracy. The LOD and LOQ values for linalool were 2.19 and 6.62 µg mL -1 and for estragole 2.001 and 6.063 µg mL -1 , respectively. The coefficients of determination ( R 2 ) were >0.99. The average recoveries ranged between 71 and 106%, with coefficient of variation ≤6.4%.