Seasonal Variability of Juniperus communis L. Berry Ethanol Extracts: 2. In Vitro Ferric Reducing Ability of Plasma (FRAP) Assay.

In the present study, the seasonal variability of the in vitro ferric reducing ability of plasma (FRAP), total phenols, and terpene hydrocarbon content in 70% ethanol extracts were evaluated. The samples of crushed (CBs) and non-crushed ripe juniper berries (NCBs) collected at five localities in North-East Slovakia during the years 2012-2014 were compared. The method of preparation of the extract influenced the amount of dry matter (DM) in the extracts. In the CB extracts were statistically higher contents of DM (from 13.91 ± 0.11 g·L-1 to 23.84 ± 0.14 g·L-1) compared to NCB extracts (from 1.39 ± 0.01 g·L-1 to 16.55 ± 0.09 g·L-1). The differences in antioxidant activity between the investigated localities were statistically significant for both types of extract. For example, in 2013 in the locality of Zbojné, the FRAP in NCBs was 76.62 µmol·L-1·g-1 DM and in CBs was 138.27 µmol·L-1·g-1 DM, while in the Milpos locality, in NCBs there was 232.66 µmol·L-1·g-1 DM and in CBs there was 1178.98 µmol·L-1·g-1 DM. The differences in the antioxidant activity between the studied years in the case of NCB extracts were not statistically significant. In the case of CB extracts, significant differences between the evaluated years were found. Statistics by ANOVA confirmed that CB extracts prepared from berries in the year 2013 showed significantly higher activity compared to CB extracts from berries from the years 2012 and 2014. Based on the Pearson we found a negative correlation coefficient between the FRAP assay and the content of total polyphenols in NCB extracts (-0.531 in 2012; -0.349 in 2013; and -0.224 in 2014). In contrast, CB extracts showed a positive correlation coefficient (0.843 in 2012; 0.742 in 2013; 0.617 in 2014).

Seasonal Variability of Juniperus communis L. Berry Ethanol Extracts: 1. In Vitro Hydroxyl Radical Scavenging Activity.

In the present study, in vitro hydroxyl radical scavenging activities, total phenols and terpene contents in 70% ethanol extracts were evaluated. Samples of crushed (CB) and non-crushed ripe juniper berries (NCB) collected at five localities in North-East Slovakia during the years 2012-2014 were compared. Standard or modified methods for determining phytochemical and antioxidant activity were used together with a novel method for the evaluation of the results after the correction of the measured values per gram of dry matter (DM). Statistically significantly higher DM contents (average values for three years) were found in the CB extracts (ranging from 18.86 to 21.91 mg/mL) in comparison to those for NCB (ranging from 2.59 to 9.90 mg/mL). Depending on the localities and years, the hydroxyl radical scavenging activity ranged from 15.52 to 32.85% for NCB and from 65.59 to 88.12% for CB, respectively. The contents of total phenols ranged from 43.75 to 246.75 mg gallic acid equivalents (GAE)/L (NCB) and from 151.84 to 278.19 mg GAE/L (CB), respectively. However, the higher content of total phenols per gram of DM was found in the NCB extracts (8.49-42.23 mg GAE/g DM) and then in CB (6.87-18.77 GAE/g DM). The results obtained in this study showed a higher efficiency for extraction from juniper berries in 70% ethanol if the pericarp was disrupted in comparison to that achieved with the maceration of intact berries.

Does the Invasive Heracleum mantegazzianum Influence Other Species by Allelopathy?

Heracleum mantegazzianum is an invasive species in middle Europe. The mode of action of its invasiveness is still not known. Our study focuses on observation of potential allelopathic influence by the production and release of phytochemicals into its environment. Plant material was collected four times within one season (April, May, June, July 2019) at locality Lekárovce (eastern Slovakia) for comparison of differences in composition and potential allelopathy. Water extracts from collected samples were used for different biological assays. The total phenols and flavonoids were determined spectrophotometrically. The profile and content of phenolic components, including coumarins, were determined by two techniques of liquid chromatography along with in vitro evaluation of the free radical scavenging activity of extracts (DPPH, Hydroxyl, Superoxide, and FRAP). The changes in composition in extracts in different seasonal periods were evident as well as potential phytotoxic activity in some concentrations on specific model plants. The slight antioxidant activity was noted. The invasiveness of the current species could be supported by the excretion of its phytochemicals into its surroundings and by different modes of action influencing living organisms in its environment.

New Mutant Amaranth Varieties as a Potential Source of Biologically Active Substances.

Amaranth species represent a diverse group of plants. Many of them are a rich source of secondary metabolites with many positive biological effects. Total phenolic, total flavonoid and rutin content, antioxidant activity against superoxide and hydroxyl radicals, FRAP (Ferric-reducing ability of plasma) assay and DPPH (2,2-Diphenyl-1-picrylhydrazyl) radical scavenging assay were determined in ethanol extracts of dried leaves of the new Slovak amaranth varieties 'Pribina' and 'Zobor'. The amount of total phenolic substances ('Pribina' GAE 38.3 mg.g-1 DM and 'Zobor' GAE 26.1 mg.g-1 DM), content of total flavonoids ('Pribina' QE 26.5 mg.g-1 DM and 'Zobor' QE 20.3 mg.g-1 DM) and rutin ('Pribina' 50.8 mg.g-1 DM and 'Zobor' 15.2 mg.g-1 DM) were higher in the variety 'Pribina', compared to the variety 'Zobor'. A statistically higher antioxidant activity against superoxide radical (1.63%·mg-1g-1 DM), hydroxyl radical (3.20%.mg-1g-1 DM), FRAP assay (292.80 µmol.L-1·mg-1.g-1 DM) and DPPH (54.2 ± 1.78 µg.mL-1 DM) were detected in the 'Pribina' variety. Antiradical and antioxidant activities of both extracts showed high positive correlations in relation to the content of total phenolic substances, total flavonoids and rutin. Amaranth is an undemanding crop on specific environmental conditions and is resistant to abiotic and biotic stress.

First Report on Evaluation of Basic Nutritional and Antioxidant Properties of Moringa Oleifera Lam. from Caribbean Island of Saint Lucia.

Moringa oleifera Lam. has been considered as a multipurpose tree. The studies on it focus on its variable nutritional benefits. It is growing in many regions, but information about nutritional properties of those growing in the Caribbean is missing. The present study focused on biochemical analysis of main nutritional and antioxidant properties in plant material-dried leaves and seeds-of Moringa oleifera. The composition of lipids, proteins, and vitamin E was evaluated in powdered dried leaves and seeds. Fatty acids were evaluated in oil extracted from the moringa seeds. Potential antioxidant properties of the moringa were evaluated in extract from crushed and powdered leaves, as well as from the powdered seeds. The total amounts of lipids, proteins, and vitamin E were higher in powdered seeds (31.85%, 35.13%, and 220.61 mg/kg) than in powdered leaves (12.48%, 20.54%, and 178.10 mg/kg). The main compound of fatty acids presented oleic acid (76.78%) in seeds' oil and oleic (25.01%), palmitic (24.84%), and linolenic (24.71%) acids in leaves. Neohesperidin (126.8 mg/kg), followed by chlorogenic acid (99.96 mg/kg) and quercetin (43.44 and 21.44 mg/kg) were main phenolic compounds identified. Total phenols in powdered leaves' extract (635.6 mg GAE/L) was higher than in powdered seeds' extract (229.5 mg GAE/L). The activity against superoxide radical and hydroxyl radical was 92.4% and 73.1% by leaves' powder extract and 83.6% and 60.7% by crushed-leaf extract; seed-powder extract exhibited a pro-oxidation activity (-68.4%) against superoxide radical and the lowest antioxidant effect against the hydroxyl radical (55.0%).

Serotonin levels in the small bowel mucosa as a marker of ischemic injury during small bowel preservation.

Of the serotonin occurring in the small bowel mucosa, 95% is present in enterochromaffine cells. The cold ischemia during small bowel transplantation results in mucosal injury and releasing of serotonin into the lumen. Because of it, the mucosal concentration of serotonin is decreasing. The aim of our study was to establish the correlation between changes in serotonin levels in small bowel mucosa during grafts preservation and cold ischemic time. Wistar rats (n= 35) weighing 322+/-18g, divided into five main groups (n= 7/group) according to the time of small bowel grafts preservation (0, 1, 6, 9, and 12 hours), were used as experimental animals. The grafts were preserved in 4 degrees C histidine-tryptophane-ketoglutarate (HTK) solution. Tissue samples for mucosal serotonin concentration measurement and for light microscopic evaluation were taken after predefined cold ischemic times. Quantitative histological assessment was made using the Park's small bowel wall injury grading scheme. The t-test for dependent samples was used for statistical analysis. The mean serotonin mucosal concentrations after 0, 1, 6, 9, and 12 hours of cold ischemic injury were 433.09+/-160.33, 402.6+/-120.53, 412.5+/-47.57 ng/mL, 190.8+/-45.88 and 145.2+/-16.78 ng/mL Statistically significant differences (p<0.05) were between 6, 9, and 12 hours of cold ischemia. Morphological changes of small bowel mucosa graded by Park's scheme after the same ischemic intervals were 0, 0.5+/-0.47, 0.97+/-0.41, 1.74+/-0.69, and 1.84+/-0.64. Statistically significant differences (p<0.05) were demonstrated between all preservation times except between 9 and 12 hours of cold ischemia. Morphological changes in small bowel mucosa correlated with cold ischemic time, as well as with serotonin mucosal concentration. These data indicate the possibility of use a serotonin concentration in small bowel mucosa as a parameter of small bowel grafts ischemic injury.

Effect of selected dimethylaminochalcones on some mitochondrial activities.

Chalcones and their synthetic cyclic analogues have been shown to possess a full scale of biological activities in a variety of experimental systems. They were assessed to be mostly effective in defense against free radicals in the organism, but several compounds exhibited cytotoxic pro-oxidant activities. The respiratory response and antioxidant status in mitochondria were investigated upon addition of 4'-dimethylaminochalcone (1a) and its cyclic analogues, (E)-2-(4'-((CH3)2 N)-benzylidene)-1-indanone (1b), -1-tetralone (1c), and -1-benzosuberone (1d). Selected structures were able to change the respiratory response of mitochondria and showed an ability to modify mitochondrial metabolic and redox efficiency, though they did not indicate redox reactivity towards glutathione in adduct-free incubations. The results of the study indicate that -chalcone and -tetralone derivatives cause suppression of reactive oxygen species affecting mitochondrial respiration by mild uncoupling. In addition, (E)-2-(4'-((CH3)2 N)-indanone (1b), and to a greater extent, -benzosuberone (1d), showed pro-oxidant effects, which partially explain their cytotoxicity.

Effects of humic acids in vitro.

Humic acids are known for their overall positive health and productivity effects in animal feeding trials and, controversially, as an aetiological factor of cancer. We tried to assess the in vitro effect of humic acids from a selected source in Slovakia when used at recommended prophylactic dosage. We investigated antioxidant properties, enzymatic and non-enzymatic antioxidant defence system in liver mitochondria and cultured cancer cell lines in vitro. We observed a significant decrease in superoxide dismutase activity after humic acids treatment irrespective of dissolving in dimethyl sulphoxide or direct addition to mitochondria suspension in a respiration medium. Activities of other antioxidant enzymes measured, such as glutathione peroxidase and glutathione reductase, showed no significant differences from the control as well as the reduced glutathione content. Percentage of inhibition by humic acids of superoxide radical indicated lower efficacy compared with that of hydroxyl radical. Survival of six different cancer cells lines indicated that only the acute T lymphoblastic leukaemia cell line was sensitive to the tested humic acids. Despite relatively low solubility in aqueous solutions, humic acids from the selected source participated in redox regulation. By recapturing the radicals, humic acids reloaded the antioxidant defensive mechanism. Results from in vitro study conducted with humic acids from the natural source showed potential of these substances as promising immunity enhancing agents.