In this study the effect of the ozonation procedure on the microbiological and antioxidant status of raspberries stored at room temperature was investigated. During the study, it was found that ozonation with a dose of 8–10 ppm for 30 min, every 12 hours, for 3 days effectively reduced the growth of aerobic mesophilic bacteria and fungi. On the last day of storage, infestation with Botrytis cinerea for control fruit amounted 100%, while for ozonated fruits it was only 12%. In addition, the ozonation process has preserved the high antioxidant potential of the fruits and reduced the loss of polyphenol compounds, including anthocyanin. The applied procedure was proven to be effective, showing the potential of ozone as a factor extending the high commercial and consumer value of fruit stored at room temperature.

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The biocidal properties of hydrogen peroxide (H2O2) could be used in plant protection. However, the effects of H2O2 foliar spraying on the performance of the potato photosynthetic apparatus are still unclear. A pot experiment was conducted to investigate the effect of foliar spraying, which was done twice, with various H2O2 concentrations (1, 3, 6, 12, and 18%) on the potato photosynthetic apparatus efficiency and antioxidant capacity. The measurements were taken four times: on the first and seventh day after each application. Foliar spraying with 1% H2O2 concentration was the most stimulating for the course of physiological processes in leaves. Further increased doses of H2O2 enhanced stress in plants which is manifested by a decrease in pigment levels, photosynthetic attributes, antioxidant capacity in leaves, and fresh mass above-ground parts of potato plants. The intensive effect of spraying was particularly observed on the first day after application, while later, the activity of the photosynthetic apparatus and antioxidant capacity increased. The study provides information that foliar spraying with 1% H2O2 can be taken into account in further research on the development of a potato plant protection methods.

We investigated the changes in the physiological and biochemical properties of potato plants exposed to differing ozone (O3) concentrations (5 ppm, 10 ppm) and exposure times (2, 4, 8, 12, 16 min) to determine the safe dose that could be used in crop protection programs. We measured the gas exchange, relative chlorophyll content, chlorophyll fluorescence and total antioxidant capacity in potato leaves exposed to O3 fumigation. The fresh weight (FW) of the aboveground part of the plants and a visual assessment of plant condition were determined after the end of the experiment. The plants were given two O3 treatments and measurements were carried out four times: on the 1st and 7th day after treatment. We conclude that O3 exposure time had a greater impact on the reduction in the efficiency of the potato photosynthetic apparatus than O3 concentration. Research has showed that O3 in 5 ppm concentration for 2 and 4 min and 10 ppm for 2 min increased the efficiency of the photosynthesis and antioxidant activity in leaf processes, and these doses could be taken into account in further research on the potential for using O3 in potato protection.

Due to a variety of physicochemical properties of the sewage sludge the selection of proper methods for its stabilization is difficult. In this work, the effect of ozone treatment on physico-chemical and microbiological parameters of sludge was investigated. Ozonation was carried out using a counter-current bed reactor, which ensures optimal mass transfer and the contact time of ozone with excessive sediment. The ozonation process was carried out for 15, 30, 45 and 60 min at an ozone concentration of 90–110 ppm. As a result of the ozone treatment it was possible to reduce the number of colony forming units. Also the potential for dewatering of the sludge improved while the total solids of the sludge did not change. The values of COD and BOD5 increased with time of the process.