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The beneficial effects of walnuts and walnut products on human health, due primarily to their rich polyphenolic content, have been appreciated as an empirical fact for centuries. The purpose of this study is to determine the polyphenolic contents of liqueurs made from the walnut selections ‘Rasna’ and ‘Sava’ and the walnut cultivar ‘Šampion’ (all harvested at three different times), as well as the polyphenolic contents of their green husks. The walnut liqueurs were prepared according to two traditional recipes using young walnut fruits. The highest antioxidant capacity was recorded in the liqueur made from the ‘Rasna’ walnut selection (89.94%), whereas the highest contents of phenols (83.28 mg GAE/g FW), flavonoids (0.83 mg QE/g FW) and proanthocyanidins were found in the liqueur made from the ‘Šampion’ cultivar (14.75 mg CE/g FW). The youngest ‘Rasna’ walnuts, harvested at the first experimental time point, exhibited the highest phenolic and tannin contents, whereas the highest flavonoid content was observed in the ‘Šampion’ cultivar. The biochemical results obtained indicate a decrease in the polyphenolic content of walnut fruits with their growth and development. Moreover, the polyphenolic profiles of the walnut liqueurs considered were found to be greatly affected by the method of preparation and the cultivar/selection of walnuts.

Flame-weeding is a very useful method for weed control, especially in organic production where the use of herbicides is prohibited. With this method heat sup­presses weeds in row within a second. Apart from this, heat also affects growing crop plants and surrounding soil. The aim of this paper was to determine the effect of different propane doses, on photosynthetic and polyphenolic (total flavonoids and anthocyаnins) pigments in soybean leaves, as well as the number of microorganisms in the soil. Soybean plants exposed to flame showed a different reaction to high temperature stress, which was reflected in differ­ent content of analyzed biochemical parameters, but the most responsive were anthocyanins. Actinomycetes turned out to be the most sensitive group of soil microorganisms affected by weed flaming, while fungi were the most tolerant.

Sweet cherries (Prunus avium L.) contain various phenolic compounds which contribute to total antioxidant activity. The present study was conducted to assess the antioxidant activity of 15 sweet cherry cultivars from Vojvodina province (north Serbia). The free radical scavenging properties of fruits were evaluated employing two different methodologies, including DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay and ferric reducing antioxidant power (FRAP) assay. Strong correlations were found between total phenolics, tannins, flavonoids and anthocyanins and DPPH and FRAP assays. In particular, cultivar Peter showed the highest antioxidant capacity and possesses the highest amount of measured phenolic compounds. This investigation shows large variability among sweet cherry cultivars in measured chemical attributes.

The purpose of this study was to analyze antioxidant systems among three invasive ragweed species, Ambrosia artemisiifolia L., A. trifida L. and Iva xanthifolia Nutt. Antioxidant capacity could be a possible marker of adaptation to variable environmen­tal conditions, since change in amount of antioxidants represents one of the first responses to various environmental stimuli. Among investigated ragweeds, I. xanthifolia leaves had more pronounced guaiacol peroxidase activity (87.5 and 62.5%) and reduced glutathione content (2.3 and 28.8%) than A. artemisiifolia and A. trifida, respectively. However, super­oxide dismutase activity was invariable in all investigated plants (234.1-247.5 U g-1 fresh weight). The highest content of total phenolics, tannins, flavonoids and proanthocyanidins were detected in A. trifida leaves (up to 3.7 - fold the amount of the others). According to antioxidant activity tests, investigated ragweed species could be presented in a scale: A. trifida > I. xanthifolia > A. artemisiifolia. Accumulation of non-enzymatic antioxidants and lower content of reduced glutathione point to different oxidative stress avoidance strategies of A. trifida when compared to A. artemisiifolia and I. xanthifolia within the same environ­mental conditions.

Due to an increase in the number of herbicide-resistant weeds and environmental concerns about the use of synthetic herbicides, a great effort is being made in designing alternative weed management strategies. The present study was carried out in order to examine the impact of winter savory (Satureja montana) aqueous extract in natural weed management. We evaluated the effect of two concentrations (0.1 and 0.2%) of S. montana aqueous extract on the activity of antioxidant enzymes and the lipid peroxidation process in Jimson weed (Datura stramonium) seedlings. Our results showed that S. montana aqueous extract induced lipid peroxidation in roots of Jimson weed seedlings 72 hours after the treatment.

Losses of grain quality and quantity as a result of insect activity during storage impose the need for proper pest control. One of the major pests of stored wheat is the lesser grain borer (LGB), Rhyzopertha dominica. This pest is usually controlled with insecticides. However, there is recently a growing interest in the use of plant-based products in pest management. Plants are a rich source of active compounds and for centuries have been used for the control of harmful insects. This study was carried out in order to evaluate the effects of Satureja montana aqueous extract on LGB adults in contact and contact-digestive tests. The mortality of LGB adults during contact exposure to S. montana extract was low, regardless of the concentration (16.7–33.3% after 24 h and 30.0–33.3% after 48 h). After 24 h of contact-digestive exposure, the highest mortality was caused by 2% S. montana extract (23.3%), while after 48 h the level of mortality increased in all treatments with S. montana extract (0.5, 1, and 2%) and was 28.4, 28.4, and 41.7%, respectively. After 72 h of contact-digestive exposure, it ranged from 57.5 to 63.5%, while in the control it remained the same (2.7%). After 7 days of such exposure, it was 91.6–98.4%, depending on the concentration. Based on the obtained results, we conclude that S. montana aqueous extract caused mortality of LGB adults, the level of this mortality depending on concentration of the applied extract and duration of the experiment

Plants which belong to Lamiaceae family are good potential sources of natural antioxidants useful for preventing oxidative stress-related diseases. The food industry is becoming increasingly interested in aromatic herbs, including plants from Lamiaceae family, because of their anti-inflammatory properties and antioxidant activities, due to growing consumer demands for healthy foods of natural origin. In the present investigation, the comparative antioxidant potential of aqueous and acetone extracts of three Lamiaceae species are described: Clinopodium menthifolium (Host), Satureja montana L., and Salvia sclarea L., using three methods: 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) radical (ABTS) scavenging, 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH) scavenging, and ferric reducing antioxidant power (FRAP) assay and their correlations with total phenolic and flavonoid contents. Antioxidant capacity showed a positive relationship comparing three above mentioned tests. Antioxidant capacity detected by antioxidant ABTS, DPPH, and FRAP assays was positively correlated with total phenolics content. Aqueous extract of C. menthifolium showed greater antioxidant potential.

Monilinia laxa Aderh. and Ruhl. is the predominant causal agent of brown rot disease of stone fruit orchards, especially sweet cherries. The objective of this study was to identify reaction in response of nine genotypes cherry, with different pomological properties, against brown rot. These genotypes were harvested at commercial maturity from orchard in the Fruit Research Institute in Rimski Šančevi. The studied genotypes showed significant differences in terms of the occurrence of disease on fruits, both under artificial inoculation and infection in the field. Given the fact that sweet cherry fruits are prone to infection by a number of pathogens in the field, biochemical parameters were analysed on artificially inoculated fruits. Biochemical analysis of fruits determined significant differences in contents of total phenols, flavonoids and anthocyanins, as well as in antioxidant activity. It was genotype specificities and intensity of infection, as well as the interaction of the two that induced differences in the secondary biomolecules content and antioxidant activity. The majority of the genotypes examined showed high polyphenolics content, while under the infection, the content was significantly lower. Based on the results obtained, the secondary metabolites content can be used as one of the parameters for evaluating the resistance of sweet cherry genotypes to brown rot.

This study was conducted in order to assess the effect of inoculation of soybean (Glycine max L.) seeds with Trichoderma asperellum, followed by mites (Tetranychus urticae) exposure on lipid peroxidation (LP) process and the activity of antioxidant enzymes. T. urticae is an occasional pest of soybean that causes biotic stress. Biotic stress leads to overproduction of reactive oxygen species (ROS) which may cause damage to vital biomolecules. Enzymatic antioxidant defense systems protect plants against oxidative stress. T. asperellum is commonly used as biocontrol agent against plant pathogens. It has been suggested that previous inoculation of seeds with T. asperellum may cause induced resistance against biotic stress. The aim of this study was to determine LP intensity and antioxidant enzymes activity in inoculated and non-inoculated soybean seedlings with and without exposure to mites. Noticeably higher LP intensity was detected in non-inoculated group treated with mites compared to control group. Inoculated soybean seedlings treated with mites had lower LP intensity compared to noninoculated group. Also, it has been noticed that inoculation with Trichoderma asperellum itself, produced mild stress in plants. In addition, positive correlation between enzymes activity and LP was noticed. The level of oxidative stress in plants was followed by the change of LP intensity. According to results obtained, it was concluded that the greatest oxidative stress occurred in non-inoculated group treated with mites and that inoculation successfully reduced oxidative stress. The results indicate that inoculation of soybean seeds with T. asperellum improves resistance of soybean seedlings against mites attack. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR-31022]

Plants are a good source of natural antioxidants and could provide protection against harmful free radicals. Phenolic compounds were found to be an important part of human diet and are considered as active principles in many medicinal and agricultural plants. Detailed information about health-promoting components of different soybean cultivars could lead to a better understanding and an increased consumption of this crop, including its use in functional foods. The objective of this study was to determine total phenolics, total tannins, total flavonoids and antioxidant capacity with different assays of five Serbian soybean cultivars (Merkur, Sava, Valjevka, Venera and Victoria) extracted with three different solvents (70% acetone, 70% ethanol and 70% methanol). Total phenolics varied among cultivars and among applied solvents. Antioxidant properties highly depended on a solvent used for extraction. Such results highlight an existing variability in soybean seeds and emphasise the need to evaluate diversity and to support conventional breeding programs to improve soybean nutritional value.

Secondary plant biomolecules are the main agents in biochemical inter­actions between plants and the environment. It is possible to distinguish the role of secondary biomolecules in allelopathic (plant-plant) activity, plant-insect, plant-microbe, plant-herbivore and others. These interactions can significantly affect the productivity of agricultural crops. Application of allelochemicals into agricultural practice may reduce the use of herbicides. Effect of Salvia sclarea L. and Clinopodium menthifolium (Host) aqueous extracts on lipid peroxidation process, as well as the activity of antioxidant enzymes in leaves and roots of Jimson weed (Datura stramonium L.) and soybean (Glycine max L.) seedlings were examined 24 h, 72 h and 120 h after the treatment. The third aim was to evaluate effectiveness of aqueous extract as contact toxicant against Rhyzopertha dominica. Our results showed that S. sclarea aqueous extract induced lipid peroxidation in roots of Jimson weed seedlings 24 h after the treatment. Furthermore, both tested concentrations of C. menthifolium aqueous extract induced lipid peroxidation in Jimson weed roots 72 h and 120 h after the treatment. It was observed that S. sclarea aqueous extract showed toxic effect against R. dominica, with high mortality rate (above 95%).

Soluble free phenolics (SP), PVPP-bound tannins (PVPP-P), flavonoids (TF) and proanthocyanidins (PA) content, as well as the DPPH-radical scavenging capability of the whole grain of 17 different Triticum spp. accessions were analyzed. The content of SP ranged from 976 to 2927 μg CE/g, while PVPP-P ranged from 335 to 1412 μg CE/g and TF from 0.16 to 1.12 μg RE/g of dry whole grain. The presence of PA in the whole grains has not been established. The values for DPPH-radical scavenging activity were rather moderate, under 40 % of neutralized radicals. A positive correlation between DPPH-activity and analyzed phenolics was recorded in twelve of seventeen genotypes (r=0.73-0.99). Trans-cinnamic acid was the major compound among phenolic acids and quercetin among flavonoids found in wheat varieties. The data obtained should enable the selection of the accessions rich in biologically active compounds that could further be processed into functional food with possible health benefits associated with higher antioxidant properties. [Projekat Ministarstva nauke Republike Srbije, br. TR-31066]

Plant-growth promoting rhizobacteria (PGPR) elicit activation of phenylpropanoid pathway in plants which leads to phenolics production and enhanced antioxidant capacity. The purpose of this work was to assess the antioxidant activity of soybean plants, Glycine max L., inoculated with PGPR (isolates of Azotobacter chroococcum, Streptomyces sp. and mixture of these) during plant development, as well as yield of inoculated soybean plants. PGPR applied in the experiment stimulated flavonoids and isoflavone synthesis, which enhanced non-enzymatic antioxidant ability of soybean plants. Also, PGPRs stimulated accumulation of daidzein and genistin in soybean seedlings (5-fold and 2-fold compared to control values, respectively). The mixture of PGPRs showed positive impact on antioxidant activity (10-20% higher activity) and yield components of soybean which proposed this inoculum as possibly potent bio-fertilizer in soybean production. [Projekat Ministarstva nauke Republike Srbije, br. TR-31022]

The objective of this work was to study the effect of treatment of young soybean plants with cholic acid of different concentrations on their oxidative status. Young soybean plants, grown hydroponically for two weeks, were treated by adding cholic acid to the nutrient solution at the concentrations 20, 40, 60 and 80 mg/L, the control being without cholic acid. After one week, several parameters of the oxidative status were determined in the leaves and roots of the plants: contents of superoxide (-O•2 ), hydroxyl radicals (•OH) and glutathione (GSH), lipid peroxidation (LP), the superoxide dismutase (SOD) activity and the soluble protein accumulation, as well as the contents of chlorophylls and carotenoids. Treatments with cholic acid increased - O•2, LP, •OH and GSH in the leaves of the treated plants, while only the OH content increased in the roots at higher cholic acid concentrations. The obtained results support the idea that cholic acid, as an elicitor of defense responses in plants, might act through the generation of an oxidative burst.

Nitrate reductase and glutamine synthetase activity, as well as free proline and soluble protein content were measured in eight soybean parent genotypes and six F1 hybrids. The aim of this study was to determine variability and the mode of inheritance for these parameters, and point out the genotypes of interest for future breeding programs. Analysed genotypes and their F1 hybrids expressed significant differences in activities of nitrate reductase and glutamine synthetase enzymes, as well as in soluble proteins and free proline contents. Since mode of inheritance for all investigated traits was in most cases dominance or heterosis, it can be concluded that these parameters are under control of dominant genes. The obtained results suggest that genotypes with favorable traits, such as variety Linda, line 1511, and F1 hybrids (Linda x LN92-7369) and (Balkan x BL-8), could be of interest as a good starting material for further breeding programs.

Composition of mineral elements has been investigated in three Salvia species (Lumiaceae) growing wild in the Vojvodina Province (Serbia), as well as in a commercial phytopreparation (tea) of Salvia officinalis L. We determined concentrations of micro- and macroelements in dried plant material in order to evaluate their nutritive and medicinal value and to indicate an easily accessible natural source that could be used as a possible food supplement. The study showed that the plants were well supplied with essential elements. Concentrations of potentially harmful heavy metals (Pb, Cd, Ni, Cr) were below their respective toxic levels. From the nutritive and medicinal aspects, the investigated Salvia species may be considered as a natural source of essential microelements, especially Fe and Cu, with a low capacity for heavy metal accumulation.

Sweet cherries (Prunus avium L.) contain various phenolic compounds which contribute to total antioxidant activity. Besides fruits, petioles also contains siginificant amount of phytonutrients and could be used for health-promoting herbal teas or infusions. Many dietary phenolics are known to provide health-improving benefits due to their various biological activities. The possible health beneficial effects included antioxidant, antialergic, anticarcinogenic, antimicrobial, antimutagenic, and antiinflamatory properties. Content of total polyphenols, tannins, and flavonoids and antioxidant capacity in a dry petioles of a number of selected sweet cherry genotypes were investigated spectrophotometrically. The differences in total polyphenolic contents, total tannins, antioxidant activity, and total flavonoid in petioles among sweet cherry genotypes were statistically significant. Total polyphenols content ranged from 12.96 to 31.85 mg gallic acid equivantents/g dry petioles weight and total tannins content ranged from 6.31 to 9.77 mg gallic acid equivalent/g dry petioles weight. Flavonoids have been knows to reduce oxidative stress in biological systems due to their antioxidant capacities. Total flavonoids were within the range 0.44-1.94 mg of rutin equivalents/g dry petioles weight. Cherries from the cultivars that are abundant in total phenolic content contained also more flavonoids. Antioxidant activity of sweet cherry petioles is related with the total polyphenolics, and flavonoids but not with tannins content. The highest total polyphenol and flavonoid content and antioxidant activity was observed in the petioles of Hedelfinger sweet cherry cultivar while the lowest antioxidant activity and total polyphenol and flavonoid content was recorded in the petioles of Rita cultivar. Genotypes with highrt poliphenolic contents also showed the higher DPPH-radicals scavenging activities. Petioles of sweet cherry fruits are a significant source of different phenolic compounds, and could be considered a good source of natural antioxidants. The difference in the sweet cherry genotypes in terms of total polyphenolics is due to genetic variations, as all genotypes were the same age and grown under the same ecological conditions. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the impact of Satureja montana L. aqueous extract on soybean antioxidant properties so as to assess its possible side effects when applied as biohebicide in soybean organic production. The effects of two concentrations (0.1% and 0.2%) of S. montana aqueous extract on the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in leaves and roots of soybean (Glycine max L.) seedlings were examined 24, 72 and 120 h after the treatment. Our results showed that the significant increase in the catalase activity was recorded in roots of soybean treated with both concentrations of the extract used. On the other hand, both concentrations of S. montana aqueous extract stimulated the significant increase of the superoxide dismutase activity in leaves and roots of soybean. Higher activity of the antioxidant enzymes in the roots of soybean compared with activity of the antioxidant enzymes in leaves showed that roots were more affected than leaves

Oxidative stress in soybean plants infected with Diaporthe isolates was evaluated in order to select (1) the least aggressive inoculation method, (2) to determine the most aggressive Diaporthe isolate, and (3) to determine the most tolerant soybean cultivar to this isolate. Based on the present malondialdehyde (MDA) content, the main end product of the lipid peroxidation process, and the biomarker for oxidative stress, the mycelium contact method was chosen as the least aggressive inoculation method, compared to the toothpick method and plug method. The activity of the antioxidant enzymes (superoxide-dismutase (SOD), catalase (CAT), and peroxidase (PX)), the reduced glutathione (GSH) content, and the level of lipid peroxidation (LP) were measured in soybean cv. Sava infected by five different Diaporthe species (DPM1F- D. aspalathi , DPC/KR19- D. caulivora , DPC004NY15- D. eres , 18-DIA-SOY-14- D. gulyae , and PL157A- D. longicolla ). The most pathogenic Diaporthe species to cv. Sava was D. eres . The screening of the antioxidant enzymes activity in the leaves of 12 different soybean cultivars (Altona, Atlas, Capital, Chico, CX134, Favorit, Lakota, McCall, Morsoy, Strain, Rubin, and Victoria) infected with D. eres by the mycelium contact inoculation method showed that Capital, McCall, and Morsoy were the cultivars with the highest tolerance to D. eres , followed by Chico, Favorit, Lakota, and Rubin. The most sensitive cultivars were Atlas, CX134, Victoria, and Strain.

Oxidative stress in soybean seedlings and the length of the soybean stem lesions infected with the fungus Macrophomina phaseolina (Tassi) Goid were evaluated to determine the most tolerant soybean cultivar to this pathogen. The level of superoxide anion radical (O 2 •- ) production, the activity of the antioxidant enzyme superoxide-dismutase (SOD), and the intensity of lipid peroxidation (LP) were measured in four soybean cultivars: Favorit, Atlas, Victoria, and Rubin. Results showed that O 2 •- radical production and SOD activity were the most elevated in the cv. Favorit inoculated with M. phaseolina , while the level of lipid peroxidation intensity was the lowest compared to the control. This indicates that the soybean cv. Favorit has managed to prevent infection with M. phaseolina . Furthermore, higher O 2 •- radical production and lower SOD enzyme activity were measured in cv. Victoria, with enhanced lipid peroxidation. This means that the cv. Victoria was infected with M. phaseolina , and was the most sensitive. None of the tested oxidative stress parameters showed a significant difference in the cvs. Atlas and Rubin compared to the control. Furthermore, the highest lesion length was measured in the cv. Victoria, followed by cv. Favorit, while the lowest lesion length was measured in the cv. Atlas followed by the cv. Rubin; and thus, the cv. Atlas followed by the cv. Rubin, were the most tolerant soybean cultivars to this pathogen.

Phytotoxic substances released by invasive plants have been reported to have anti-pathogen, anti-herbivore, and allelopathic activity. The aim of this study was to determine the allelopathic influence of the Ambrosia trifida L. on oxidative stress parameters (the lipid peroxidation process; reduced glutathione (GSH) content; and activity of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), and peroxidase (PX)) and phenolic compounds (total phenolic and tannin content) in maize ( Zea mays L.), soybean ( Glycine max L.), and sunflower ( Helianthus annuus L.) crops to explore the effect of released allelochemicals through A. trifida root on crops. An analysis by HPLC confirmed the presence of protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, and syringic acid as major components in the A. trifida . Based on the obtained results for oxidative stress parameters, it can be concluded that the sunflower was the most sensitive species to A. trifida allelochemicals among the tested crops. The other two crops tested showed a different sensitivity to A. trifida . The soybean did not show sensitivity, while the maize showed sensitivity only 10 days after the sowing.

Pinus nigra Arn. bark extracts from Mokra gora (MG) and Tara mountains were analyzed with regard to their polyphenolic profile and antioxidative and antiproliferative activity. The ethanol extract from MG showed the highest phenolic, flavonoid, tannin, and proanthocyanidin content when compared with the acetone and methanol extracts from both sites. The same extract exhibited the highest ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) and ferric reducing antioxidant power (FRAP) radical scavenging ability and total antioxidant activity (TAA). On the basis of high-performance liquid chromatography analysis, catechin, caffeic, syringic, p-coumaric, and ferulic acids were predominantly present in the MG extracts. The ethanol extract from MG was rich in syringic acid, epicatechin and its derivatives, and ferulic acid and its derivatives. The bark extracts also exerted a high cytotoxic bioactivity against all evaluated cell lines (HeLa, MCF7, HT-29, and MRC-5). The antiproliferative activity of P. nigra bark is probably related to the ferulic acid content and its synergistic activity to caffeic acid and taxifolin. The antioxidative role of the presented phenols was confirmed through the obtained significant linear correlation between the total phenolic content and DPPH (r = .934) as well as the FRAP% of the extracts (r = .948). Also, the TAA significantly depended on the proanthocyanidins (r = .902) and tannin contents (r = .914). The composition of the presented compounds could be related to promising antioxidant and antiproliferative efficacy of MG bark., (© 2021 Deutsche Pharmazeutische Gesellschaft.)