Phenolic Compound Profile and Antioxidant Capacity of Flax (Linum usitatissimum L.) Harvested at Different Growth Stages.

The profile of phenolic compounds changes during the growth of a plant and this change affects its antioxidant potential. The aim of this research has been to find the growth stage of flax with the highest antioxidant capacity, and to determine the phenolic compounds responsible for such a capacity. Flax was harvested in six growth stages: from stem extension to mature seeds. The phenolic compounds were identified using LC-TOF-MS and quantified in an extract and in the fresh matter (FM) of each growth stage. The radical scavenging activity against ABTS•+ and DPPH•, the ferric-reducing antioxidant power (FRAP), and the antioxidant activity in the ß-carotene-linoleic acid emulsion system were determined. Mono- and di-C-glycosyl flavones were found to be the most abundant phenolics of the aerial parts of flax, which also showed the highest content of isoorientin (210-538 µg/g FM). Coniferin, its derivative, and hydroxycinnamic acid derivatives were also detected. The plant was richer in flavone C-glycosides from stem extension to seed ripening (1105-1413 µg/g FM) than at the mature seed stage (557 µg/g FM). Most of the individual flavone C-glycoside contents in the extracts decreased when increasingly older plants were considered; however, the isoorientin content did not change significantly from the steam extension to the seed ripening stages. The antiradical activity against ABTS•+ and FRAP was higher for the aerial parts of the flax harvested at the flowering, brown capsule, and seed ripening stages, mainly due to the presence of flavone C-glycosides. The oxidation of ß-carotene-linoleic acid emulsion was instead inhibited more effectively by the extracts from plants at the brown capsule and mature seed stages. Coniferin and its derivative were significantly involved in this activity. The extracts from the aerial parts of the flax harvested from flowering to seed ripening could be a valuable source of flavone C-glycosides for use as nutraceuticals and components of functional foods.

Micronized Powder of Raspberry Pomace as a Source of Bioactive Compounds.

Red raspberries, which contain a variety of nutrients and phytochemicals that are beneficial for human health, can be utilized as a raw material in the creation of several supplements. This research suggests micronized powder of raspberry pomace production. The molecular characteristics (FTIR), sugar, and biological potential (phenolic compounds and antioxidant activity) of micronized raspberry powders were investigated. FTIR spectroscopy results revealed spectral changes in the ranges with maxima at ~1720, 1635, and 1326, as well as intensity changes in practically the entire spectral range analyzed. The discrepancies clearly indicate that the micronization of the raspberry byproduct samples cleaved the intramolecular hydrogen bonds in the polysaccharides present in the samples, thus increasing the respective content of simple saccharides. In comparison to the control powders, more glucose and fructose were recovered from the micronized samples of the raspberry powders. The study's micronized powders were found to contain nine different types of phenolic compounds, including rutin, elagic acid derivatives, cyanidin-3-sophoroside, cyanidin-3-(2-glucosylrutinoside), cyanidin-3-rutinoside, pelargonidin-3-rutinoside, and elagic acid derivatives. Significantly higher concentrations of ellagic acid and ellagic acid derivatives and rutin were found in the micronized samples than in the control sample. The antioxidant potential assessed by ABTS and FRAP significantly increased following the micronization procedure.

Effect of Fertilization on Phenolics of Rapeseeds and Their Antioxidant Potential.

Three varieties of rapeseed (Castilla, California, and Nelson F1) were cultivated using medium-intensive (control), intensive, and economical (spare) technologies with different nitrogen and sulfur fertilization techniques. The antioxidant potential of rapeseeds was investigated using ABTS, FRAP, and DPPH assays. The content of total phenolic compounds was determined using the Folin-Ciocalteu phenol reagent. The profile of phenolic compounds was determined using high-performance liquid chromatography (HPLC). Diversifying fertilization in various ways influenced the content of phenolic compounds in extracts of rapeseed. In extracts from the Nelson F1 rapeseeds, intensive cultivation resulted in a lower content of phenolic compounds compared to the control group. Economic fertilization reduced the content of phenolic compounds in seeds from the California variety. HPLC chromatograms of the extracts were characterized by the presence of five (California and Castilla) and six (Nelson F1) main phenolic compounds. Two compounds were identified as sinapine and sinapic acid; others were classified as derivatives of sinapic acid. The effect of fertilization on the antioxidant activity of the seeds and their extracts varied depending on the plant variety and antioxidant assay. For the Castilla and California varieties, no differences were found in the results of the ABTS assay. The antiradical activity against ABTS•+ of extracts from the Nelson F1 intensive and spare cultivated seeds was higher than that of extracts from control seeds. The FRAP values of extracts/seeds from the Castilla variety cultivated using different methods did not differ significantly. The results of the DPPH assay were not affected by fertilization in the case of extracts from the California and Castilla varieties. However, the extracts from spare cultivated seeds of Nelson F1 exhibited stronger antiradical activity against DPPH•. These findings highlight the complex relationship between fertilization practices, phenolic compound accumulation, and antioxidant activity in rapeseed. Integrating varietal traits and cultivation practices is crucial for optimizing the nutritional benefits of rapeseed.

Outcomes of Transcatheter Aortic Valve Implantation Comparing Medtronic's Evolut PRO and Evolut R: A Systematic Review and Meta-Analysis of Observational Studies.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has become a broadly acceptable alternative to AV surgery in patients with aortic stenosis (AS). New valve designs are becoming available to address the shortcomings of their predecessors and improve clinical outcomes. METHODS: A systematic review and meta-analysis was carried out to compare Medtronic's Evolut PRO, a new valve, with the previous Evolut R design. Procedural, functional and clinical endpoints according to the VARC-2 criteria were assessed. RESULTS: Eleven observational studies involving N = 12,363 patients were included. Evolut PRO patients differed regarding age (p < 0.001), sex (p < 0.001) and STS-PROM estimated risk. There was no difference between the two devices in terms of TAVI-related early complications and clinical endpoints. A 35% reduction of the risk of moderate-to-severe paravalvular leak (PVL) favoring the Evolut PRO was observed (RR 0.66, 95%CI, [0.52, 0.86] p = 0.002; I2 = 0%). Similarly, Evolut PRO-treated patients demonstrated a reduction of over 35% in the risk of serious bleeding as compared with the Evolut R (RR 0.63, 95%CI, [0.41, 0.96]; p = 0.03; I2 = 39%), without differences in major vascular complications. CONCLUSIONS: The evidence shows good short-term outcomes of both the Evolut PRO and Evolut R prostheses, with no differences in clinical and procedural endpoints. The Evolut PRO was associated with a lower rate of moderate-to-severe PVL and major bleeding.

The impact of Morus alba L. leaf extract on intestinal ion transport. An in vitro study.

Morus alba L. (White mulberry), is an important and popular herbal plant of the Moraceae family. It has been widely used due to its therapeutic properties, which include antidiabetic, antibacterial, anti-inflammatory, cardiovascular, and hypolpidemic activity. The present study evaluates the effects of aqueous white mulberry leaf extract on the transepithelial ion pathway in the rabbit colon epithelium (n = 48), using electrophysiological methods. In addition, the antioxidant potential and the chemical composition of the extract were determined. A mechanical-chemical stimulation with white mulberry in RH fluid (MB-RH) caused a statistically significant (p < 0.001) increase in the transepithelial electrical potential difference, from - 0.130 to - 0.685 mV. Gentle washing of the intestine with white mulberry in bumetanide, used as inhibitor of transepithelial chloride pathways, resulted in 14.8% shorter reaction than during MB-RH stimulation. There were no statistically significant differences between the electric potential values measured during stimulation with amiloride solution, used as inhibitor of transepithelial sodium pathways, and white mulberry in amilorid solution (p = 0.485). A short-term application of extract to the colon epithelium is responsible for local and reversible inhibition of chloride ion channels. The extract enhances sodium ion absorption and consequently changes the electrical potential. The effect of white mulberry extract on sodium ion transport may be related to the mechanism of hypoglycaemic activity of mulberry leaves.

Synergistic, additive, and antagonistic antioxidant effects in the mixtures of curcumin with (-)-epicatechin and with a green tea fraction containing (-)-epicatechin.

The combinations of curcumin with green tea flavan-3-ols produce various synergistic biological effects. This study aimed to verify the antioxidant effects in mixtures of curcumin with (-)-epicatechin (EC) or with EC fraction from green tea in a non-polar lipid system (triacylglycerol autoxidation) and in a polar conditions (ABTS assay). Curcumin was 2.5-2.6 and 2.9-3.6 times weaker antioxidant than EC and EC fraction, respectively. The synergism was found in mixtures using the isobologram analysis of ABTS•+ scavenging activity results. The strongest effect with a combination index of 0.751 was in the equimolar mixture of pure compounds. In the lipid system, antagonism occurred for curcumin and EC fraction combination. However, an additive effect was found between curcumin and EC. In conclusion, the antioxidant effects in the curcumin and EC mixtures depended on the polarity of the assay media, the ratio of antioxidants, and presence other phenolics in the system.

Sunflower (Helianthus annuus L.) Plants at Various Growth Stages Subjected to Extraction-Comparison of the Antioxidant Activity and Phenolic Profile.

The aim of this study was to evaluate the differences in the antioxidant activity and phenolic profile of sunflower (Helianthus annuus L.) extracts obtained from the aerial parts of plants harvested at five growth stages. In vitro assays were used to determine the antioxidant activity, i.e., ABTS•+ and DPPH• scavenging activity, the ferric-reducing antioxidant power (FRAP) and the ability to inhibit ß-carotene-linoleic acid emulsion oxidation. Phenolic compounds, such as mono- and dicaffeoylquinic acid isomers and caffeic acid hexose, were identified using the LC-TOF-MS/MS technique. The predominant compound during the growth cycle of the plant was 3,5-di-O-caffeoylquinic acid, whose content was the highest at the mid-flowering stage. The total phenolic content was also the highest in sunflowers at the mid-flowering stage. The main phenolic compound contents were closely correlated with ABTS•+ and DPPH• scavenging activity and FRAP. No significant correlation was found between the total phenolic content and the antioxidant activity in the emulsion system. The highest antiradical activity and FRAP were generally determined in older plants (mid-flowering and late flowering stages). In conclusion, the aerial parts of sunflowers, in particular those harvested at the mid-flowering stage, are a good plant material from which to obtain phenolic compound extracts, albeit mainly of one class (esters of caffeic acid and quinic acid), with high antioxidant activity.

Antioxidant Activity and Phenolic Composition of Amaranth (Amaranthus caudatus) during Plant Growth.

The antioxidant activity and phenolic composition of the aerial part of Amaranthus caudatus at seven stages of development were investigated. Total phenolic content, ABTS•+, DPPH•, and O2•- scavenging activity, ferric-reducing antioxidant power (FRAP), and Fe2+ chelating ability were evaluated. The phenolic profile was characterized by 17 compounds. Rutin was predominant in all growth stages, although its content, similar to the quantity of other phenolics, changed during the growth cycle. Flavonols were most abundant in the plants of early flowering and grain fill stages. In contrast, the highest content of hydroxycinnamic acid derivatives was found in the early vegetative stage. The results of antioxidant assays also showed significant differences among plant stages. Generally, the lowest antioxidant activity was found in the shooting and budding stages. Significantly higher activity was observed in amaranths in earlier (vegetative) and later (early flowering and grain fill) stages, suggesting that plants in these stages are valuable sources of antioxidants.

Protein precipitating capacity and antioxidant activity of Turkish Tombul hazelnut phenolic extract and its fractions.

Natural (raw) hazelnut was extracted with 80% (v/v) acetone to obtain crude phenolic extract that was then fractionated for elution of low-molecular weight (LMW) and high-molecular weight (HMW) fractions. LMW fraction was further purified (LWM-FP) to remove sugars and organic acids. The crude extract and its fractions were determined by measuring their protein precipitating capacity (PPC) using two different proteins [bovine serum albumin (BSA) and gelatin], molecular weights, total phenolics, condensed tannins, and various antioxidant activities. Significant differences (p<0.05) existed in the contents of total phenolics, condensed tannins, antioxidant activities, and PPC among the crude extract and fractions, albeit to different extends. BSA and gelatin was effectively precipitated by HMW fraction. HMW fraction had the highest total phenolics, condensed tannins, and antioxidant activities, followed by crude extract, LWM-FP, and LMW, respectively. The present study suggests that HMW fraction could be utilised as a source of polyphenols for the food industry.

Effects of Gamma-Irradiation on the Antioxidant Potential of Traditional Bulgarian Teas.

Food irradiation technologies are used to reduce the risk of food bome diseases by eliminating pathogenic microorganisms, prolonging shelf life and reducing storage losses by delaying ripening, germination or sprouting. However, application of irradiation in food technology can negatively influence the biologically active compounds in foods. In this research, the effect of gamma-irradiation on the antioxidant activity of Bulgarian teas was investigated. The aim of the study was to evaluate the total phenolic and tannin content and antioxidant activity of ethanolic extracts of Bulgarian herbal teas before and after gamma-irradiation. Mursalski tea (Sideritis scardica), Mashterka tea (Thymus serpyllum), Good Night tea (tea mix), Staroplaninski tea (Balkan tea mix), Trakia tea (tea mix), and Mountain tea (Planinski tea mix) were selected for this study. Gamma-irradiation was applied at the absorbed dose of 5 kGy. Antioxidant activity of non- irradiated and irradiated teas was determined by measuring antiradical activity against DPPH' and ABTS and the ability to reduce ferrous ions. The highest total-phenolic content was found in Mursalski tea (268 mg/g), and the highest tannin content in Good Night tea (168 mg/g). FRAP, TEAC and DPPH assays revealed that the most active samples were Staroplaninski (2.78 mmol Fe (II)/g), Planinski (0.87 mmol Trolox/g) and Planinski (0.032 mg/mL), respectively. The radical scavenging activity of irradiated tea samples was maintained after gamma-irradiation. The most interesting extract from irradiated tea studied was Staroplaninski, which demonstrated a higher antioxidant potential in the irradiated sample compared with the non-irradiated sample.

Fine tuning of trehalose biosynthesis and hydrolysis as novel tools for the generation of abiotic stress tolerant plants.

The impact of abiotic stress on plant growth and development has been and still is a major research topic. An important pathway that has been linked to abiotic stress tolerance is the trehalose biosynthetic pathway. Recent findings showed that trehalose metabolism is also important for normal plant growth and development. The intermediate compound - trehalose-6-phosphate (T6P) - is now confirmed to act as a sensor for available sucrose, hereby directly influencing the type of response to the changing environmental conditions. This is possible because T6P and/or trehalose or their biosynthetic enzymes are part of complex interaction networks with other crucial hormone and sugar-induced signaling pathways, which may function at different developmental stages. Because of its effect on plant growth and development, modification of trehalose biosynthesis, either at the level of T6P synthesis, T6P hydrolysis, or trehalose hydrolysis, has been utilized to try to improve crop yield and biomass. It was shown that alteration of the amounts of either T6P and/or trehalose did result in increased stress tolerance, but also resulted in many unexpected phenotypic alterations. A main challenge is to characterize the part of the signaling pathway resulting in improved stress tolerance, without affecting the pathways resulting in the unwanted phenotypes. One such specific pathway where modification of trehalose metabolism improved stress tolerance, without any side effects, was recently obtained by overexpression of trehalase, which results in a more sensitive reaction of the stomatal guard cells and closing of the stomata under drought stress conditions. We have used the data that have been obtained from different studies to generate the optimal plant that can be constructed based on modifications of trehalose metabolism.

Protective effects of equimolar mixtures of monomer and dimer of dehydrozingerone with α-tocopherol and/or ascorbyl palmitate during bulk lipid autoxidation.

Protective effects of recently synthesised dehydrozingerone, M1OH (which is one half of the molecule of curcumin) and dimer of dehydrozingerone, D1(OH)2, as individual compounds (1 mM) and as equimolar binary (1:1) and ternary (1:1:1) mixtures with α-tocopherol (TOH) and/or ascorbyl palmitate (AscPH), were studied during bulk lipid autoxidation at 80 °C. The highest oxidation stability of lipid substrate, in the presence of individual compounds, was found for TOH, followed by D1(OH)2 and M1OH, determined from the main kinetic parameters (antioxidant efficiency, reactivity and capacity). AscPH did not show any protective effect. Synergism was obtained for the binary mixtures of (TOH+AscPH) [42.4%], (M1OH+TOH) [32.4%] and (M1OH+AscPH) [35.6%] and for the ternary mixture of (M1OH+TOH+AscPH) [28.7%]. Different protective effects observed were explained on the basis (of results) of TOH regeneration and its content determined by HPLC. These antioxidant binary and ternary mixtures can be used as functional components of foods with health-promoting effects.