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.

The purpose of this study was to investigate the biological properties of an extract obtained from the waste of blueberry fruit. The study covered the optimization of extraction of antioxidants from blueberry pomace and the determination of antioxidant properties of the extract using HaCaT as the model organism. Research showed that the yield of antioxidants extraction from blueberry waste was dependent on the applied extraction conditions. Based on the mathematical models, the optimal conditions of extraction process in which the maximum quantity of antioxidant compounds is achieved from the waste mass unit, i.e., the relation of the waste mass to the volume of ethanol equal to 1:17.36, and process time equal to 1000 s. The obtained extract was characterized by high antioxidant activity, which was shaped by high content of polyphenols, mainly anthocyanins. Moreover, the extract showed a high ability to protect HaCaT cells from the occurrence of oxidative stress induced by H₂O₂. Cells treated with the extract and H₂O₂ generated a lower amount of ROS than cells treated with H₂O₂ only. The obtained results will be base of further studies on applying the extract in production of diet supplements and functional foods with increased antioxidant activity. Moreover, the main research material is blueberry pomace which is a troublesome waste material for juice producers. Consequently, according to a sustainable development idea, the study results will provide an opportunity to increase interest in the problem of rational use of the waste material to a certain extent.

The major aim of this study was to investigate the effect of ozonation process on the level of oxidative stress markers in blueberry fruit during cold storage (4 °C). Blueberry (Vaccinum corymbosum L.) fruit was ozonated with an ozone concentration of 15 ppm for 30 min, every 12 h for 28 days of storage at 4 °C. The results indicated that ozone treatment activated a defense mechanism against oxidative stress in blueberry fruit. Ozonated fruit was characterized by higher activity of antioxidant enzymes i.e. superoxide dismutase, glutathione peroxidase, and phenylalanine ammonia-lyase than non-ozonated fruit, over the first 21 days of storage. In turn, the level of superoxide anion radical and hydrogen peroxide in ozonated fruit was significantly lower compared with the untreated material. However, after 21 days of storage, ozone treatment contributed to the oxidative modification of protein which could be a reason of decreasing enzymes activity, involved in cell protection against oxidative stress.