Comprehensive Analysis of Highbush Blueberry Plants Propagated In Vitro and Conventionally

In vitro culture allows the production of numerous plants with both desirable and undesirable traits. To investigate the impact of the propagation method on highbush blueberry plants, an analysis was performed on four groups of differentially propagated plants: in vitro with axillary (TC-Ax) or adventitious shoots (TC-Ad), conventionally (SC) and using a mixed method (TC/SC). The analysis included plant features (shoot length and branching, chlorophyll and fluorescence and DNA methylation) and fruit properties (antioxidant compounds). The data obtained indicated significant differences between plants propagated conventionally and in vitro, as well as variations among plants derived from in vitro cultures with different types of explants. SC plants generally exhibited the lowest values of morphological and physiological parameters but produced fruits richest in antioxidant compounds. TC/SC plants were dominant in length, branching and fluorescence. Conversely, TC-Ax plants produced fruits with the lowest levels of antioxidant compounds. The methylation-sensitive amplified polymorphism (MSAP) technique was employed to detect molecular differences. TC-Ad plants showed the highest methylation level, whereas SC plants had the lowest. The overall methylation level varied among differentially propagated plants. It can be speculated that the differences among the analysed plants may be attributed to variations in DNA methylation.

In Vitro Analysis of Selected Antioxidant and Biological Properties of the Extract from Large-Fruited Cranberry Fruits

This study investigated the in vitro antioxidant and biological properties of ethanol extracts obtained from the fruits of the highbush cranberry. The produced extracts exhibited a high content of polyphenols (1041.9 mg 100 g d.m.-1) and a high antioxidant activity (2271.2 mg TE g 100 d.m.-1 using the DPPH method, 1781.5 mg TE g 100 d.m.-1 using the ABTS method), as well as a substantial amount of vitamin C (418.2 mg 100 g d.m.-1). These extracts also demonstrated significant in vitro biological activity. Studies conducted on the Saccharomyces cerevisiae cellular model revealed the strong antioxidant effects of the extract, attributed to a significant reduction in the levels of reactive oxygen species (ROS) within the cells, confirming the utility of the extracts in mitigating oxidative stress. Moreover, inhibitory properties were demonstrated against factors activating metabolic processes characteristic of inflammatory conditions. It was observed that the cranberry extract inhibits the activity of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) non-selectively. Additionally, the extract was found to be a highly active inhibitor of acetylcholinesterase (AChE), potentially suggesting the applicability of this extract in the prevention of neurodegenerative diseases, including Alzheimer's disease.

Dual mechanism of silver nanoparticle-mediated upregulation of adipogenesis in mouse fibroblasts (3T3-L1) in vitro

Silver nanoparticles (AgNPs) are widespread in the environment due to the increase in their application e.g. in medicine as part of hard-to-heal wound dressings. Many studies have revealed easy diffusion of AgNPs into deep skin layers through damaged epidermis and contact with e.g. fibroblasts. Therefore, the aim of this study was to evaluate the impact of small-size AgNPs (10 nm) in ppm concentrations on the adipogenesis process in mouse embryo fibroblasts (3T3-L1). The results showed a decrease in the metabolic activity, followed by an increase in the reactive oxygen species (ROS) level in a dose- and time-dependent manner (0-20 ppm). The increased caspase-3 activity was observed only at the highest concentration (20 ppm) of AgNPs. Further analysis showed the ability of the tested NPs to increase the lipid accumulation in adipocytes, similar to ROSI [peroxisome proliferator-activated receptor gamma (PPARγ) agonist], measured by Oil-Red-O staining. Moreover, the analyses evidenced the ability of AgNPs to increase the lipoxygenase activity and malondialdehyde levels, which is probably based on ROS-dependent enhancement of lipid hydroperoxidation. Lastly, a significant increase in the PPARγ, Adiponectin, Resistin, Vegf, and Serpine mRNA expression was shown 6 h after the induction of the differentiation process. Based on the obtained results, it can be concluded that small-size AgNPs increase adipogenesis via ROS- and PPARγ-based mechanisms with potential engagement of crosstalk with the aryl hydrocarbon receptor, which is important due to the widespread application of AgNPs in medicine. However, more studies are needed to elucidate the full mechanism of these NPs in the tested cell model in depth.

Physiological and Morphological Implications of Using Composts with Different Compositions in the Production of Cucumber Seedlings

Compost has a broad application in terms of the improvement of the soil properties. This research work was conducted to present the molecular implications of using compost obtained from different substrates to improve soil parameters for cucumber seedlings cultivation. In the experiment, the following compost mixtures were used: sewage sludge (80%) + sawdust (20%); sewage sludge (40%) + sawdust (10%) + biodegradable garden and park waste (50%); biodegradable garden and park waste (90%) + sawdust (10%); sewage sludge (80%) + sawdust (20%) + Eisenia fetida; sewage sludge (40%) + sawdust (10%) + biodegradable garden and park waste (50%) + Eisenia fetida; biodegradable garden and park waste (90%) + sawdust (10%) + Eisenia fetida. The final substrate compositions consisted of compost mixtures and deacidified peat(O) (pH 6.97; Corg content-55%, N content-2.3%), serving as a structural additive, in different mass ratios (mass %). The produced plants underwent biometric and physiological measurements as well as enzymatic analyses of stress markers. Based on the conducted studies, it has been found that the substrate productivity depends not only on the content of nutrient components but also on their structure, which is moderated by the proportion of peat in the substrate. The most effective and promising substrate for cucumber seedling production was variant 2 (I), which consisted of 25% compost from sewage sludge (40%) + sawdust (10%) + biodegradable garden and park waste (50%) and 75% deacidified peat. Despite the richness of the other substrates, inferior parameters of the produced seedlings were observed. The analysis of the enzymatic activity of stress markers showed that these substrates caused stress in the plants produced. The study's results showed that this stress was caused by the presence of Eisenia fetida, which damaged the developing root system of plants in the limited volume of substrate (production containers). The adverse influence of Eisenia fetida on the plants produced could possibly be eliminated by thermal treatment of the compost, although this could lead to significant changes in composition.

Effect of postharvest nicotinamide treatment on NAD+ metabolism and redox status in strawberry fruit during storage

The increased activity of PARP enzymes is associated with a deficiency of NAD+, as well as with a loss of NADPH and ATP, and consequent deterioration of the redox state in fruits. In this study, we checked whether treatment with nicotinamide (NAM) would affect PARP-1 expression and NAD+ metabolism in strawberry fruit during storage. For this purpose, strawberry fruits were treated with 10 mM NAM and co-treated with NAM and UV-C, and then stored for 5 days at 4 °C. Research showed that nicotinamide contributes to reducing oxidative stress level by reducing PARP-1 mRNA gene expression and the protein level resulting in higher NAD+ availability, as well as improving energy metabolism and NADPH levels in fruits, regardless of whether they are exposed to UV-C. The above effects cause fruits treated with nicotinamide to be characterised by higher anti-radical activity, and a lower level of reactive oxygen species in the tissue.

Variability of Properties Modulating the Biosynthesis of Biologically Active Compounds in Young Barley Treated with Ozonated Water

This paper presents the effects of irrigating barley plants with different type of water solutions saturated with gaseous ozone generated from atmospheric air. The study investigated the effects of the applied types of water on the modulation of the biosynthesis of selected bioactive compounds (content of total polyphenols, small molecule antioxidants, vitamin C) in the produced plant material. A number of transformations of reactive oxygen species (ROS) and nitrogen compounds have also been postulated; these are observed during the saturation of water with gaseous O₃ and 30 min after the end of the process. It was shown that after the process of water saturation with gaseous O₃, the gas later is converted to compounds with high oxidative potential and good stability; these, in turn, lead to the oxidation of oxidates generated from atmospheric nitrogen into nitrates, which exhibit fertilising properties. Thirty minutes after the process of H₂O saturation with gaseous O₃ was completed, the tests showed the highest concentrations of nitrates and the relatively high oxidative potential of the solution originating from H₂O₂ with a low concentration of the dissolved O₃. This solution exhibited the highest activity modulating the biosynthesis of polyphenols, small molecule antioxidants and vitamin C in young barley plants. The resulting differences were significant, and they were reflected by 15% higher total polyphenol content, 35% higher antioxidative potential and 57% greater content of vitamin C compared to the control specimens (plants treated with fresh H₂O).

Edible coating enriched with cinnamon oil reduces the oxidative stress and improves the quality of strawberry fruit stored at room temperature

BACKGROUND

The present study aimed to assess the impact of a starch/gelatine coating containing cinnamon oil on selected quality attributes and redox status in strawberry fruit stored at room temperature (72 h).

RESULTS

Research showed that the application of cinnamon oil to an edible coating allows an improvement of the quality of strawberry fruit stored at room temperature. The cinnamon oil coating inhibits the development of yeast and mould, and reduces loss of soluble solids and ascorbic acid during 72 h storage at room temperature. Moreover, the coating with cinnamon oil clearly reduced the level of oxidative stress, which was manifested by a lower level of reactive oxygen species, as well as a lower activity of antioxidant enzymes. The elimination of oxidative stress in the cinnamon oil-coated fruit also contributed to lower PARP1 mRNA expression, inhibiting the metabolism of NAD⁺ and reducing ATP losses.

CONCLUSION

The coating of strawberry fruit with a starch/gelatine biofilm containing cinnamon oil is an effective method for delaying postharvest senescence of fruit and the storage degradation of tissue. © 2023 Society of Chemical Industry.

The Modification of Substrate in the Soilless Cultivation of Raspberries (Rubus Idaeus L.) as a Factor Stimulating the Biosynthesis of Selected Bioactive Compounds in Fruits

Raspberry fruits are a valuable source of bioactive compounds. The study used the modification of the substrate (coconut fibre), consisting of the use of various organic and mineral additives, in the soilless cultivation of raspberries. The additives influenced the biosynthesis of bioactive compounds in the raspberry fruits by modifying the sorption properties and the abundance of the substrate. The influence of the additives on the content of polyphenols was determined as well as their profile (UPLC-MS), antioxidant potential (ABTS), vitamin C content, and the activity of selected enzymes that are markers of stress and resistance to abiotic factors. In the study, a significant effect of these additives was observed on the biosynthesis of polyphenols in raspberry fruit. The highest increase in the content of these compounds in relation to the control sample (substrate-100% coconut fibre), namely 37.7%, was recorded in the case of fruit produced on coconut substrate enriched with sheep wool. These fruits were also characterised by a significantly different profile of these compounds. These changes were caused by readily available ammonium nitrogen and free amino acids in the decomposition of proteins contained in the sheep wool. This was confirmed by the recorded content of chlorophyll SPAD in the plant leaves and the activity of selected enzymes, which proves a low level of stress and good condition of the plants.

One-time ozone treatment improves the postharvest quality and antioxidant activity of Actinidia arguta fruit

The major aim of this study was to check the effect of one-time ozonation on selected quality parameters and antioxidant status of Actinidia arguta fruit. For this purpose, A. arguta fruit was ozonated with gas at a concentration of 10 and 100 ppm, which was carried out successively for 5, 15 and 30 min. Next, the selected quality attributes, antioxidants level as well as NADPH and mitochondrial energy metabolism in mini-kiwi fruit after ozonation were analysed. Our research has shown that ozonation reduced the level of yeast and mould without affecting the content of soluble solids or acidity. In turn, ozonation clearly influenced the antioxidant activity and the redox status of the fruit. The ozonated fruit was characterised by a lower level of ROS due to the higher level of low molecular weight antioxidants, as well as the higher activity of superoxide dismutase and catalase. In addition, improved quality and antioxidant activity of the fruit were indirectly due to improved energy metabolism and NADPH level. The ozonated fruit showed a higher level of ATP, due to both higher activity of succinate dehydrogenase and higher availability of NADH. Moreover, the increased level of NAD⁺ and the activity of NAD⁺ kinase and glucose-6-phosphate dehydrogenase contributed to higher levels of NADPH in the fruit.

Induction of Biosynthesis Antioxidant Molecules in Young Barley Plants by Trioxygen

Young barley plants are a good source of bioactive compounds. This paper presents the effects of gaseous O3 (trioxygen or ozone) on the biosynthesis of compounds, determining the antioxidant potential of young barley plants. The total content of polyphenols was determined along with their profile, as well as total antioxidant potential and vitamin C content. The highest contents of these compounds were identified in young barley plants exposed to gaseous O3. The main bioactive compound, representing polyphenols, determined in the examined raw materials was saponarin (isovitexin 7-O-glucoside). The induction of increased biosynthesis of these molecules was directly linked to the modification of the activity of selected enzymes. The increased polyphenol content resulted from the modified activities of polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL). On the other hand, the oxidative effect of ozone on barley plants was reduced, owing to the modified activities of catalases (CAT), glutathione peroxidases (SOD) and guaiacol peroxidase (GPOX). Analysis of the results showed that by applying gaseous O3 at a dose of 50 ppm for 10 min, the contents of bioactive compounds can be maximised in a residue-free way by activating oxidative stress defence mechanisms.

Ozonation process causes changes in PARP-1 expression and the metabolism of NADPH in strawberry fruit during storage

In this study, the effect of ozonation process on the poly(ADP-ribose) polymerase 1 gene expression (PARP-1) and related the NADPH metabolism in strawberry fruit during storage was determined. Our results showed that ozonation with gas at both 10 and 100 ppm concentrations increased the expression of PARP-1 in the fruit during storage. Furthermore, the ozonation process initially increased the level of NAD⁺ and NADH in the fruit, which corresponds to a higher ATP level. The storage of the fruit in an ozone atmosphere also contributed to increased activity of the NAD⁺ kinase, leading to increased levels of NADP⁺ . In turn, the higher activity of glucose-6-phosphate dehydrogenase caused the ozonated fruit to show a higher level of NADPH. However, as the storage period extended and thus with increasing expression of PARP-1 in the ozonated fruit, the level of NAD⁺ decreased. In general, the ozonated fruit, which had a higher level of NADPH, showed a higher content of reduced glutathione, which in turn contributed to an increase in the antioxidant activity of the fruit and, ultimately, to a lower accumulation of reactive oxygen species.

Triclosan (TCS) affects the level of DNA methylation in the human oral squamous cell carcinoma (SCC-15) cell line in a nontoxic concentration

The oral cancer is presumably caused by genetic factors and exposure to substances derived from cosmetics and disinfectants. Triclosan (TCS) is widely spread in many consumer products and oral care products. Since TCS can affect DNA methylation, which is one of the key mechanisms of gene expression that may lead to cancerogenesis, it is necessary to study this mechanism in oral cell carcinoma. The aim of the present study was to evaluate the impact of TCS on metabolic parameters, oxidative stress, gene expression, and DNA methylation and hydroxymethylation in the SCC-15 cell line. The experiments have shown TCS toxicity to SCC-15 cells only in the highest concentrations of 50 and 100 µM. TCS in a wide range of concentrations increases ROS production and caspase-3 activity. Our experiments have shown that TCS in the nontoxic concentrations of 10 µM exerts an impact on SOD2 mRNA expression and SOD activity in the SCC-15 cell line. Finally, our experiments have demonstrated that 6-h treatment with TCS decreases the mRNA expression of DNMT3A and DNMT3B. After 72-h exposure to TCS, an increased level of 5-methylcytosine and 5-hydroxymethylcytosine was observed in the SCC-15 cell line, but it was abolished by the NAC treatment. However, it is very likely that these results can be an effect of TET enzyme activity, especially in the case of the decrease in 5mC and the increase in 5hmC after the 48-h exposure to TCS, which was accompanied with a decrease in the mRNA expression of DNMT3A and DNMT3B.

Assessment of the Impact of the Application of a Quercetin-Copper Complex on the Course of Physiological and Biochemical Processes in Wheat Plants (Triticum aestivum L.) Growing under Saline Conditions

Salt stress is one of the main stressors limiting plant growth and yield. As a result of salt stress, unfavorable changes in the photosynthesis process take place, leading to a decrease in plant productivity. Therefore, it is necessary to use biologically active substances that reduce the effects of this stress. An example of such a substance is quercetin, classified as a flavonoid, which plays an important role in alleviating the effects of salt stress, mainly by the inactivation of reactive oxygen species (ROS) and by improvement of the photosynthesis process. A study was made of the effect of the quercetin–copper complex (Q-Cu (II)), which has a stronger antioxidant effect than pure quercetin. By means of a pot experiment, the influence of solutions of the Q-Cu (II) complex (100 mg∙L⁻¹ [Q1], 500 mg∙L⁻¹ [Q2] and 1000 mg∙L⁻¹ [Q3]) on the physiological and biochemical processes occurring in wheat plants subjected to salt stress was investigated. The plants were given two sprays of Q-Cu (II) solution, and their physiological parameters were examined both 1 and 7 days after each application of this solution. The level of ROS and the activity of antioxidant enzymes (catalase [CAT], superoxide dismutase [SOD] and guaiacol peroxidase [GPOX]) were also determined. It has been shown that spraying with Q2 and Q3 solutions improves the chlorophyll content, the values of chlorophyll fluorescence parameters (the photochemical efficiency of PS II [F_v/F_m], the maximum quantum yield of primary photochemistry [F_v/F₀], and the performance index of PS II [PI]), and gas exchange (net photosynthetic rate [P_n], stomatal conductance [g_s], transpiration rate [E] and intercellular CO₂ concentration [C_i]). As a result of the application of Q2 and Q3 solutions, the level of ROS and the activity of the antioxidant enzymes tested decreased, which means that these concentrations are most effective in counteracting the effects of salt stress.

Changes in the activity of flavanone 3β-hydroxylase in blueberry fruit during storage in ozone-enriched atmosphere

BACKGROUND

The present study aimed to determine whether the ozonation process affects the flavonoid biosynthesis in highbush blueberry (Vaccinum corymbosum L.) fruit. Flavanone 3β-hydroxylase (F3H) was used as a marker of the flavonoid biosynthesis pathway. The activity of F3H, the expression of gene encoding F3H and the antioxidant status in blueberries treated with ozone at a concentration of 15 ppm for 30 min, every 12 h of storage, and maintained at 4 °C for 4 weeks were investigated.

RESULTS

The results showed that ozonation process increases the expression of the F3H gene after 1 week of storage, which translates into a higher catalytic capacity of protein, as well as a higher content of flavonoids and total antioxidant potential of ozonated blueberries compared to non-ozonated fruits.

CONCLUSION

The present study provides experimental evidence indicating that ozone treatment in proposed process conditions positively affects flavonoid metabolism in highbush blueberry fruit leading to the maintainance of the high quality of the fruit during storage. © 2021 Society of Chemical Industry.

Characterisation of Some Phytochemicals Extracted from Black Elder (Sambucus nigra L.) Flowers Subjected to Ozone Treatment

Elderflowers are a well-known source of bioactive compounds. The amount of isolated bioactive compounds may be increased by applying various abiotic and biotic factors. Gaseous ozone (10 and 100 ppm) was used in the process of preparing flowers. Next, the flowers were treated with sugar syrup to extract bioactive compounds. It was shown that this treatment, including the influence of extraction temperature, significantly affects the contents of polyphenols (liquid chromatography-mass spectrometry (LC-MS) methods) and vitamin C, as well as the antioxidant potential (cupric reducing antioxidant capacity (CUPRAC method)), the profile of volatile substances (head space-solid-phase microextraction (HS-SPME methods)) and the colour of the syrup (Commission Internationale de l'Eclairage (CIE) L*a*b* methods). The findings show that an increased dose of ozone and higher extraction temperature applied in the process of syrup production resulted in higher contents and different compositions of bioactive compounds. The highest contents of bioactive compounds were identified in syrup obtained from raw material treated with ozone for 15 min (concentration = 10 ppm) and extraction with sugar syrup at a temperature of 60 °C.

The Role of Mitochondrial Energy Metabolism in Shaping the Quality of Highbush Blueberry Fruit During Storage in Ozone-Enriched Atmosphere

The aim of this study was to evaluate the effect of ozone treatment on the mitochondrial energy metabolism in blueberry fruit during storage as well as to determine the relationship between the activity of mitochondria and the antioxidative properties of ozonated fruit. Blueberry fruit was stored for 28 days at 4 °C and ozonated daily with gaseous ozone at the concentration of 15 mg L−1 for 30 min, every 12 h of storage. Research showed that ozonated fruit was characterized by higher activity of enzymes involved in oxidative phosphorylation (by 58.7% for SDH, 118.2% for CCO, and 78.16% for H+-ATPase after 7 days, respectively) than non-ozonated sample, which contributed to reduction of the loss of energy charge and ATP in the fruit during storage. Moreover, the increased activity of mitochondria led to the growth of mitochondrial ROS accumulation which, in turn, activated defense mechanisms against oxidative stress in the fruit. These metabolic responses might collectively contribute to increase the antioxidative properties of ozonated fruit and consequently to maintain a good quality of the fruit over a long period of storage.

Physiological Response of Maize Plants (Zea mays L.) to the Use of the Potassium Quercetin Derivative

Plant production technologies based solely on the improvement of plants themselves face obstacles resulting from the natural limitations of the biological potential of varieties. Therefore, new substances are sought that positively influence the growth and development of plants and increase resistance to various biotic and abiotic stresses, which also translates into an increase in obtained yields. The exogenous application of various phytoprotectants shows great promise in terms of cost effectiveness compared to traditional breeding methods or transgenic approaches in relation to increasing plant tolerance to abiotic stresses. Quercetin is a strong antioxidant among phenolic compounds, and it plays a physiological and biochemical role in plants. As such, the aim of this research was to assess the effect of an aqueous solution of a quercetin derivative with potassium, applied in various concentrations (0.5%, 1.0%, 3.0% and 5.0%), on the efficiency of the photosynthetic apparatus and biochemical properties of maize. Among the tested variants, compared to the control, the most stimulating effect on the course of physiological processes (PN, gs, ci, CCI, Fv/Fm, Fv/F0, PI) in maize leaves was found in 3.0 and 5.0% aqueous solutions of the quercetin derivative. The highest total antioxidant capacity and total content of polyphenolic compounds were found for plants sprayed with 5.0% quercetin derivative solution; therefore, in this study, the optimal concentration could not be clearly selected.

Effect of ozone treatment on glutathione (GSH) status in selected berry fruit

The major aim of this study was to investigate the effect of one-time ozone elicitation on glutathione metabolism in selected berry fruit. Raspberry, highbush blueberry, strawberry, blackberry and blackcurrant fruit was ozonated with an ozone concentration of 15 ppm for 30 min. Research showed that ozonation process causes clear and positive changes in the metabolism of glutathione in berries. After ozonation, the fruit was characterized by increased level of glutathione (GSH), which resulted from higher activity of glutathione synthetase. Moreover, ozonation improved the metabolism activity of mitochondria leading to an increase in biosynthesis of ATP, which is the source of energy necessary for the GSH production. The higher activity of the enzymes involved in glutathione metabolism i.e. glutathione peroxidase and glutathione reductase and increased level of glutathione contributed to the higher ability of the fruit to scavenging the hydrogen peroxide.

Entrapment of silver nanoparticles in L-α-phosphatidylcholine/cholesterol-based liposomes mitigates the oxidative stress in human keratinocyte (HaCaT) cells

Encapsulation procedures are used to decrease the contact of toxic nanoparticles with cells; however, this field is still not well explored. Therefore, the aim of this paper was to evaluate the effect of encapsulation of silver nanoparticles in L-α-phosphatidylcholine/cholesterol-based liposomes on a human keratinocyte cell line (HaCaT). The homogenous (PdI = 0.171) spherical (~161 nm diameter) complexes were prepared by thin film hydration with the extrusion method. The UV-Vis scan and Dynamic Light Scattering measurement did not show any "free" silver nanoparticles in solutions, which was confirmed by Transmission Electron Microscope analysis. Moreover, the liposomes were tested on HaCaT cells, showing that the encapsulation process reduced the toxicity by 30%-10% at the 100 nM and 1 pM concentrations, respectively, in comparison to "free" nanoparticles, measured by resazurin reduction and lactate dehydrogenase release assays. Moreover, the caspase-3 activity was lower after 48-h treatment with LipoAgNPs than with AgNPs. The level of reactive oxygen species (ROS) after 1, 6, 48, and 72 h of treatment of HaCaT cells was significantly lower in comparison to cells treated with "bare" silver nanoparticles analyzed with the H₂DCF-DA probe. The metabolic activity was strictly correlated with toxicity, indicating a lower negative impact of encapsulated nanoparticles than the "bare" ones.

Extraction of Antioxidant Compounds from Blueberry Fruit Waste and Evaluation of Their In Vitro Biological Activity in Human Keratinocytes (HaCaT)

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.

Effect of Ozone Treatment on the Quality of Sea Buckthorn (Hippophae rhamnoides L.)

The aim of this research was to show the effect of the ozonation process on the quality of sea buckthorn (Hippophae rhamnoides L.). The quality of the ozonated berries of sea buckthorn was assessed. Prior to and after the ozone treatment, a number of parameters, including the mechanical properties, moisture content, microbial load, content of bioactive compounds, and composition of volatile compounds, were determined. The influence of the ozonation process on the composition of volatile compounds and mechanical properties was demonstrated. The ozonation had negligible impact on the weight and moisture of the samples immediately following the treatment. Significant differences in water content were recorded after 7 days of storage. It was shown that the highest dose of ozone (concentration and process time) amounting to 100 ppm for 30 min significantly reduced the water loss. The microbiological analyses showed the effect of ozone on the total count of aerobic bacteria, yeast, and mold. The applied process conditions resulted in the reduction of the number of aerobic bacteria colonies by 3 log cfu g-1 compared to the control (non-ozonated) sample, whereas the number of yeast and mold colonies decreased by 1 log cfu g-1 after the application of 100 ppm ozone gas for 30 min. As a consequence, ozone treatment enhanced the plant quality and extended plant's storage life.

Effects of Ozone Treatment on Microbial Status and the Contents of Selected Bioactive Compounds in Origanum majorana L. Plants

This study presents the effects of ozone treatment on microbial status and contents of selected bioactive compounds in marjoram plants. Origanum majorana L. is a widely used plant which in the course of production is affected by microbial infections. One of the ways to reduce microbial load involves application of a strong oxidant, such as ozone. In order to determine the effects of ozonation, a number of analyses were carried out including microbiological tests (aerobic colony count, yeast and mould count, and mesophilic lactic acid bacteria count) and chemical tests assessing total antioxidant potential, total polyphenols, and volatile fraction composition. Ultimately, the findings showed considerable (6-log) reduction in microbial load, with unchanged composition of headspace volatile compounds. Furthermore, the raw material obtained presented elevated the contents of the selected bioactive compounds. It was shown that the most beneficial effects are achieved when ozone treatment is applied at a rate of 1 ppm for a duration of 10 min.

Impact of ozonation process on the level of selected oxidative stress markers in raspberries stored at room temperature

The purpose of this study was to investigate the impact of ozonation process on the level of oxidative stress markers in raspberries stored at room temperature. Raspberry fruit was ozonated with an ozone concentration of 8-10 ppm for 30 min, every 12 h, for 72 h of storage at room temperature. Research showed that ozonated raspberries were characterized by higher activity of superoxide dismutase, ascorbate peroxidase and phenylalanine ammonia-lyase. In turn, the ability to generate superoxide anion radical and hydrogen peroxide by ozone-treated fruit was significantly lower than in the control sample due to higher activities of ROS detoxification systems.

Onion skin extract as a protective agent against oxidative stress in Saccharomyces cerevisiae induced by cadmium

Onion skin extract is a source of bioactive compounds demonstrating a high antioxidant activity. The purpose of this research was to investigate the effect of onion skin extract at the level of oxidative stress markers in Saccharomyces cerevisiae exposed to cadmium. The generation of reactive oxygen species (ROS), antioxidant enzymes activity, total content of glutathione, and the level of lipid peroxidation in yeast cells were determined. Research showed that onion skin extract protected the yeast cells from the occurrence of oxidative stress induced by cadmium. Cells treated with onion skin extract and cadmium were characterized by lower generation of ROS, antioxidant enzymes activity, lipid peroxidation, and higher level of glutathione content than cells treated with cadmium only. However, the protective effect was dependent on the onion skin extract concentration in yeast medium. PRACTICAL APPLICATIONS: The presented studies are of comprehensive character regarding antioxidant properties of the onion skin extract, using Saccharomyces cerevisiae as a model organism. The research results give the opportunity to conduct further research on the use of onion skin extract in functional food or dietary supplements production, as a cellular protector against negative consequence of oxidative stress. It should also be mentioned that the major research material was onion skin which is a troublesome waste material for onion producers. Consequently, the study result will, to a certain extent provide an opportunity to increase interest in the problem of rational use of the waste material, according to a sustainable development idea.