Autoallelopathic potential of aqueous extracts from Canadian goldenrod (Solidago canadensis L.) and giant goldenrod (S. gigantea Aiton)

Production of allelopathic substances is a factor determining the ecological success of invasive plants—Canadian goldenrod (S. canadensis L.) and giant goldenrod (S. gigantea Aiton). This research aimed at evaluating the autoallelopathic effect of aqueous extracts (AEs) prepared from various parts of Canadian goldenrod and giant goldenrod against vegetative growth, and biomass accumulation of both goldenrods. In the stage of 5–6 leaves, goldenrod plants, were foliar sprayed with AEs, at concentrations of 5 or 10%. The biochemical properties of AEs, i.e., total phenolic content, total antioxidant potential and selected plant hormones, were examined. Two and ten days after spraying (DAS), damages to aboveground parts of goldenrods (necrosis and wilting) were visually assessed. The fresh mass of above- and belowground parts of goldenrods were measured 21 DAS. AEs from various parts of Canadian goldenrod or giant goldenrod displayed autoallelopathic properties of inhibitory nature. The phytotoxic potential of AEs varied depending on their source. Canadian goldenrod was more susceptible to the AEs, manifested by more significant damages to aboveground parts and a greater decrease in above- and belowground biomass. The most effective against growth and development of Canadian goldenrod and giant goldenrod were AEs from rhizomes, which caused a reduction of fresh biomass of goldenrods up to 42%, compared to water-treated control.

Oxidative Stress and Alterations of Paraoxonases in Atopic Dermatitis

Background: previous studies reported the involvement of reactive oxygen species (ROS) and lipid peroxidation in the pathogenesis of inflammatory skin diseases. The aim of our study was to investigate the relationship between oxidative stress and inflammation in children affected by atopic dermatitis (AD), a chronic relapsing inflammatory skin disease. Methods: levels of lipid hydroperoxides, total antioxidant capacity, and activities of the enzymes myeloperoxidase (MPO), PON1, and PON2/3 were investigated in 56 atopic pediatric patients, and compared with 48 sex-/age-matched healthy controls. Results: significantly higher levels of lipid hydroperoxides and lower values of total antioxidant potential were observed in the serum of AD children compared to that of the controls. Significant lower PON1 activities, and a significant increase in levels of MPO were observed in serum of patients, with a higher serum MPO level/PON1 paraoxonase activity ratio in patients compared to that in the controls. Significantly lower lactonase activity of PON enzymes was observed in polymorphonuclear cells isolated from AD patients. Statistically negative correlation was established between the activity of intracellular PON2/3 activity and ROS levels. Conclusions: our data confirmed that AD is associated with higher oxidative damage and a decrease in antioxidant defense. Moreover, alterations of extracellular and intracellular PON activity can promote lipoprotein dysfunction in AD patients.

Antioxidation Defenses of Apis mellifera Queens and Workers Respond to Imidacloprid in Different Age-Dependent Ways: Old Queens Are Resistant, Foragers Are Not

We investigated how different antioxidant defenses (ADSs) were shaped by evolution in young/old Apis mellifera workers and queens to broaden the limited knowledge on whether ADSs are effective in contemporary pesticide environments and to complete bee oxidative-aging theory. We acquired 1-day-old, 20-day-old, and 2-year-old queens and 1-day-old and 20-day-old workers (foragers) fed 0, 5, or 200 ppb imidacloprid, a pesticide oxidative stressor. The activities of catalase, glutathione peroxidase, glutathione S-transferase, and superoxide dismutase and the level of total antioxidant potential were determined in hemolymph. The ADS was upregulated in workers with age but downregulated in queens. Imidacloprid suppressed the ADS in all workers, particularly in foragers with an upregulated ADS, but it did not affect the ADS in 1-day-old queens. In contrast to foragers, the downregulated ADS of 2-year-old queens was unexpectedly highly upregulated by imidacloprid, which has not been previously shown in such old queens. The principal component analysis confirmed that queen and worker ADSs responded to imidacloprid in opposite ways, and ADS of 2-year-queens was markedly different from those of others. Thus, evolutionary shaped ADSs of older queens and workers may be of the limited use for foragers dwelling in pesticide ecosystems, but not for old queens.

Effect of Fertilisation on the Quality of Dried Coriander (Coriandrum sativum L.) and Lovage (Levisticum officinale)

The study presents the effects of fertilisation on selected quality parameters of the dried material obtained from plants of lovage and coriander. During the crop production process, the plants were treated with two fertilisers containing substances potentially acting as elicitors. The dried material was obtained in course of a drying process carried out in optimum conditions and based on the CD-VMFD method which combines convective pre-drying (CD) at a low temperature (40 °C) with vacuum-microwave finish drying with the use of 240 W microwaves (VMFD). The quality of the dried material was evaluated through measurement of the total contents of polyphenols, total antioxidant potential (ABTS and DPPH method), and the profile of volatile compounds (headspace-solid phase microextractio-HS-SPME) as well as assessment of the colour. It was found that by applying first fertilisation (with organic components) it is possible to significantly increase the contents of both bioactive compounds and volatile substances responsible for the aroma. It was determined that the higher content of bioactive compounds was related to the composition of the first fertiliser, presumably the extract from common nettle. The study showed that the application of the first fertiliser contributed to enhanced quality parameters of the raw material obtained.

Changes in the antioxidative properties of honeys during their fermentation

The aim of this preliminary study was to investigate whether the fermentation process affects the antioxidative properties of honeys. Therefore, the total antioxidant potential (TAP) of eleven meads was examined. TAPs were estimated using DPPH, hydroxyl radicals, and amperometric measurements in the flow-through HPLC system. The results were correlated with the total content of polyphenols and anthocyanins. Additionally, the concentrations of ethanol, sugars, and hydrogen peroxide were measured. The influence of side reactions and the presence of hydrogen peroxide, glucose, ethanol, and anthocyanins on the free radicals generation were also tested. The use of HPLC electrochemical detection for TAP measurements is particularly preferred. Depending on the potential used, different antioxidants can be measured. It turned out that fruit and species meads are characterized by much higher TAPs measured at high potential of the working electrode than at lower potential due to the high concentration of weak antioxidants which do not provide signals at low potentials. It was found that dark honeys (buckwheat, honeydew) are characterized by much higher TAP values than light ones (acacia, linden, multi-floral). The concentration of anthocyanins decreased during fermentation. They are removed together with the sediment.

Identification of Flavonoids by LC-MS/MS in Leaves Extract From Protium heptaphyllum (Aubl.) March and Antioxidant Activity in Mice

Background: Protium heptaphyllum (Aubl.) March resin is accepted as an analgesic, healing, expectorant, anti-inflammatory, antinociceptive and gastroprotective. However, there are no specific studies with leaves of this plant. Objective: This study identified the chemical composition and biological activity of crude ethanolic extract (EE) and ethyl acetate (EA) fraction from P. heptaphyllum. Methods: Mice were intoxicated with acetaminophen (PCM; 250 mg/kg), subsequently treated with EE and EA (100 mg/kg) for 7 days via gavage. Plasma analyzes and liver and kidney homogenates of the animals were performed. Results: The extract and fraction showed the presence of phenols and flavonoids. Three main flavonoids were identified by HPLC-UV, LC-MS/MS fractionation, quercetin-3-β-D-glycoside, myricetin and quercetin. For total antioxidant potential tests, EE presented EC50 of 75 μg/mL and 100 μg/mL for EA. ALT, AST and ALP enzymes activity increased in the PCM-exposed plasma, but EA decreased these activities at control levels for ALT and AST. Animal glycemic levels decreased with EE and EA, which may be due to a possible hypoglycemic effect of the plant. In liver tissue, SOD was unchanged, CAT, GSH and ASA decreased in the PCM group, but EA was able to reverse these effects. TBARS and PC were reduced by both treatments. In renal tissue, EA fraction recovered GST activity, GSH levels were restored by EE and EA and PC was reduced by treatments. Conclusion: This antioxidant effect may be due to the presence of the flavonoids identified which are already well known for their antioxidant properties.

Estimation of the total antioxidant potential in the meat samples using thin-layer chromatography

There is limited literature on the antioxidative properties of food of animal origin. Measurements of antioxidative properties are usually performed using the reaction of reduction of colored 2,2-diphenyl-1-picrylhydrazyl (DPPH) radials. Changes of the DPPH color are tracked photometrically. These measurements are interfered by both, the tested samples and reduced DPPH. This study aims to demonstrate the ability to separate different forms of DPPH (DPPH• and DPPH-H) by thin-layer chromatography (TLC). Further, it has been practically applied in the study of the determination of antioxidative properties of the meat samples. It was found that TLC can be used for the separation of different forms of DPPH as well as for measurement of TAP (total antioxidant potential) values related to the DPPH•. The strongest antioxidant properties were observed for pork neck extracted in buffer pH 2 and for smoked salmon fish extracted in acetone, the lowest for veal and turkey fillet extracted in methanol.

Salivary FRAP as A Marker of Chronic Kidney Disease Progression in Children

Chronic kidney disease (CKD) is one of the most common modern-age diseases in children. Kidney failure does not reveal any symptoms for a long time; therefore, new biomarkers are sought, preferably those reflecting an early stage of CKD. The aim of our study was to evaluate total antioxidant potential as a biomarker differentiating the degree of CKD advancement. The study included 30 children with CKD and a control group matched by age and gender. Non-stimulated saliva (NWS), stimulated saliva (SWS), plasma and urine were used as study material. Total antioxidant potential was determined spectrophotometrically using the FRAP method (ferric ion reducing antioxidant parameter) by measuring total FRAP and uric acid (UA)-independent FRAP (FRAP-UA). We demonstrated that total FRAP, FRAP-UA and UA were significantly higher in stimulated saliva, as well as urine of CKD patients compared to the controls. These biomarkers increase with the progression of chronic kidney disease and their concentration in SWS reflects their content in urine. Interestingly, salivary FRAP and uric acid clearly differentiate between various stages of CKD as well as between healthy and ill children. Special attention should be paid to total FRAP which—measured in SWS—distinguishes patients with mildly to moderately decreased kidney function from those with severe renal impairment (AUC = 1, sensitivity = 100%, specificity = 100%). Although salivary FRAP may be a potential CKD biomarker in children, further studies are needed in a larger group of patients.

Antioxidative Properties of Selected Polish Honeys

The antioxidative activities of honeys collected in Poland were screened. The total antioxidant potential (TAP) provides more information about the system than the determination of individual antioxidant. TAP is proportional to the sum of products of concentrations of all antioxidants in the sample and their antioxidant powers (rate constants). To measure, compare and correlate TAPs, we used techniques which we had recently elaborated (i) related to hydroxyl radicals, (ii) RP-HPLC measurements with amperometric detection and (iii) differential pulsed voltammetry (DPV). They were correlated with techniques already described in the literature (i) related to the DPPH radicals, (ii) the total content of phenolic compounds and (iii) color intensity. All assays revealed the following order of obtained TAP values: buckwheat > honeydew > linden > multi-flower> acacia honey. Correlations were found between results obtained using different techniques. There was also a significant correlation with the results obtained by authors using other measurement techniques. Differences in antioxidant properties among individual honeys are inversely proportional to the strength of the radicals in relation to which measurements were performed. This is due to the fact that strong radicals react not only with strong antioxidants but also with weak ones, which are much more common. The darker honeys were also observed to be characterized by higher TAP values.