Search Results (430)

Plants belonging to the genus Maytenus are members of the Celastraceae family. They have been widely used by different peoples as treatment for curing many diseases. The aim of this study was to explore the anti-inflammatory and antioxidant properties of Maytenus elaeodendroides stem bark extracts, an endemic Cuban plant. The antioxidant activity of four extracts (EtOH, EtOAc, n-BuOH, and diethyl ether/petroleum ether 1:1) was determined using DPPH and FRAP methods. Meanwhile, anti-inflammatory effects by the edema method were induced by croton oil in the mouse ear. The investigated extracts showed radical reduction capacity and prevented ear inflammation at doses of 4 mg/ear. In addition, FIA/ESI/IT/MSⁿ was used to determine the qualitative chemical composition of the EtOAc extract and allowed the identification of five flavan-3-ol monomers, four dimers, and other proanthocyanidin oligomers. From this extract three flavan-3-ol compounds (elaeocyanidin and 4′-O-methylgallocatechin), one of them new (2′-hydroxy-4′-methoxy-epigallocatechin), and a proanthocyanidin dimer (afzelechin-($4\mathsf{\beta }\text{→}8$)-4′-O-methylepigallocatechin) were isolated and identified by the chromatographic method and spectroscopic techniques, mainly ESI-MS and NMR spectroscopic methods. Full article

This is the first study to report on high performance thin layer chromatography (HPTLC) generated spectrophotometric data to systematically capture flavonoid compounds using optimized derivatization with either AlCl₃ or NaNO₂-AlCl₃-NaOH as visualisation reagents. While the traditional AlCl₃ colorimetric method using UV–Vis analysis provides valuable insights into the presence of flavonoids and allows derivation of the total flavonoid content (TFC) of a sample, HPTLC fingerprints obtained after spraying with AlCl₃ or NaNO₂-AlCl₃-NaOH enable the visualization of the various flavonoids present in a sample based on their respective absorption shifts, thus complementing the traditional TFC assay. In this study, 40 different flavonoids representing different classes (flavonols, flavanolols, flavan-3-ol, flavones, flavanones, and isoflavonoids) were analysed. Upon derivatization with AlCl₃ most of the investigated flavonoids recorded bathochromic shifts, yielding characteristic λ_max values between 370 and 420 nm, while spraying with NaNO₂-AlCl₃-NaOH triggered hyperchromic shifts, and thus an increase in absorbance intensity in flavonoids with particular substitution patterns. A few non-flavonoid components with structural similarities to flavonoids (e.g., rosmarinic acid, gallic acid, aspirin, salicylic acid) served as the negative control in this study to determine whether the derivatization reagents allowed exclusive detection of flavonoids. The method was then applied to the analysis of flavonoid containing supplements as well as red clover honey to demonstrate the method’s application in the analysis of natural products. Full article

Wine phenolic compounds, often known as polyphenols, are a diverse group of secondary bioactive compounds derived from grapes. They play a crucial role in defining the sensory characteristics, functionality, and health benefits of wine. This review explores the complex chemistry of these compounds, focusing on key classes such as flavonoids, which include flavanones, flavonols, anthocyanins, and flavan-3-ols, and non-flavonoids, such as hydroxycinnamic acids, hydroxybenzoic acids, and stilbenes. The health benefits of wine phenolics, particularly their antioxidant and anti-inflammatory properties, are also discussed in relation to preventing and reducing the risk of non-communicable diseases (NCDs) such as cardiovascular diseases, cancers, and neurodegenerative conditions. Furthermore, this review summarized the most current data from human population-based research that investigated the bioactivity of these red wine phytochemicals with relevant health benefits for NCDs. Finally, this review proposes some perspectives for future research to better understand the bioavailability, metabolism, and long-term health effects of these compounds. Full article

Drying is one of the most commonly used methods for food preservation, and in spice processing, it has a significant impact on quality. In this paper, the influences of drying at room temperature, 60 °C, and 90 °C and freeze-drying on celery and parsley roots and turmeric rhizomes were examined. The highest content of total phenolics was found in celery dried at 60 °C (C60), parsley at room temperature (PRT), and freeze-dried turmeric (TFD) (1.44, 1.58, and 44.92 mg GAE/g_dm, respectively). Celery dried at room temperature (CRT), PRT, and TFD showed the highest antioxidant activity regarding the DPPH and ABTS radicals and FRAP. The analysis of color parameters revealed that celery dried at 90 °C (C90); PFD and TFD showed the most similar values to control samples. The drying process was optimized using a combination of standard score (SS) and artificial neural network (ANN) methods. The ANN model effectively evaluated the significance of drying parameters, demonstrating high predictive accuracy for total phenolics, total flavonoids, total flavonols, total flavan-3-ols, IC₅₀^ABTS, and FRAP. TFD showed the strongest α-glucosidase inhibitory potential. Also, TFD extract showed good antibacterial activity against Staphylococcus aureus but not against Escherichia coli. C90 and PFD extracts did not show antibacterial activity against the tested microorganisms. Full article

Few investigations have been conducted to evaluate pressurized liquid extraction (PLE) technology as a sustainable method for the recovery of phenolic compounds of grape seed by-products. In this study, PLE combined with an experimental design was evaluated for optimizing the sustainable extraction of phenolic compounds from grape seed by-products. The solvent ethanol content (X1, 0–100%), temperature (X2, 20–100 °C) and time (X3, 1–11 min) were studied as independent experimental factors. Yield, TPC, antioxidant activity and phenolic composition were analyzed as optimized dependent variables. Two optimal extraction conditions at different temperatures (20 °C and 100 °C) were found, but thermal degradations at 100 °C allowed for selecting the optimal condition as 75% ethanol, 11 min and 20 °C. The optimal extracts showed high phenolic content (TPC = 350.80 ± 3.97 mg GAE/g extract) and antioxidant activity (ABTS, 9.31 ± 0.33 mmol Trolox/g extract), mainly composed of polymeric and mono-oligomeric flavan-3-ols. The digestion process reduced the TPC and antioxidant activity due to the low bioaccessibility of the flavan-3-ols, mainly as catechin, epicatechin and polymeric proanthocyanidin losses during the digestion process. However, increases in the antioxidant activity of the basolateral side (DDPH, 0.061 ± 0.000 mmol Trolox/g extract) were determined after in vitro transepithelial transport, which is a consequence of bioavailable catechin and epicatechin and reduced amounts of dimer B₂, dimer B₁, epicatechin gallate and gallic acid. Consequently, PLE combined with hydroalcoholic solvents at a low temperature resulted in a valuable methodology to obtain sustainable extracts from grape seed by-products (contributing to the circular economy), containing bioavailable phenolic compounds, which are able to increase the antioxidant status. Full article

The primary aim of this research was to identify the structural characteristics of three newly derived procyanidins from cold plasma-treated (–)-epicatechin, known for their anti-inflammatory properties. The newly generated compounds were isolated through column chromatography, and their chemical structures were elucidated through spectroscopic data analyses, including both one-dimensional and two-dimensional nuclear magnetic resonance (NMR) and mass spectrometry (MS) techniques. Furthermore, their absolute configurations were determined via circular dichroism (CD) spectroscopy. The inhibitory activity of the isolated compounds on nitric oxide (NO) production and expression levels of inducible NO synthase (iNOS) in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages was evaluated. Three new procyanidins—methylenetrisepicatechin (2), isomethylenetrisepicatechin (3), and methylenebisepicatechin (4)—along with two reported dimeric flavan-3-ols (5 and 6), were identified from plasma-treated (–)-epicatechin (1). The unique oligomerized products 2 and 3 linked by methylene bridges significantly suppressed both NO production and iNOS expression, demonstrating higher anti-inflammatory activities in LPS-stimulated RAW 264.7 cells compared with the parent compound. The newly oligomerized procyanidins have potential applications in the treatment of inflammatory diseases owing to their significant anti-inflammatory properties. Full article

The flavonoids play important roles in plant salt tolerance. Blueberries (Vaccinium spp.) are extremely sensitive to soil salt increases. Therefore, improving the salt resistance of blueberries by increasing the flavonoid content is crucial for the development of the blueberry industry. To explore the underlying molecular mechanism, we performed an integrated analysis of the metabolome and transcriptome of blueberry leaves under salt stress. We identified 525 differentially accumulated metabolites (DAMs) under salt stress vs. control treatment, primarily including members of the flavonoid class. We also identified 20,920 differentially expressed genes (DEGs) based on transcriptome data; of these, 568 differentially expressed transcription factors (TFs) were annotated, and bHLH123, OsHSP20, and HSP20 TFs might be responsible for blueberry leaf salt tolerance. DEGs involved in the flavonoid biosynthesis pathway were significantly enriched at almost all stages of salt stress. Salt treatment upregulated the expression of most flavonoid biosynthetic pathway genes and promoted the accumulation of flavonols, flavonol glycosides, flavans, proanthocyanidins, and anthocyanins. Correlation analysis suggested that 4-coumarate CoA ligases (4CL5 and 4CL1) play important roles in the accumulation of flavonols (quercetin and pinoquercetin) and flavan-3-ol (epicatechin and prodelphinidin C2) under salt stress, respectively. The flavonoid 3′5′-hydroxylases (F3′5′H) regulate anthocyanin (cyanidin 3-O-beta-D-sambubioside and delphinidin-3-O-glucoside chloride) biosynthesis, and leucoanthocyanidin reductases (LAR) are crucial for the biosynthesis of epicatechin and prodelphinidin C2 during salt stress. Taken together, it is one of the future breeding goals to cultivate salt-resistant blueberry varieties by increasing the expression of flavonoid biosynthetic genes, especially 4CL, F3′5′H, and LAR genes, to promote flavonoid content in blueberry leaves. Full article

Cotoneaster zabelii is a medicinal plant that is beneficial due to its polyphenol-rich leaves. In the course of optimizing the harvest time for C. zabelii cultivated in Poland, the leaf samples were collected monthly during the annual plant vegetation season, and the hydromethanolic leaf extracts were evaluated for their phenolic composition and model biological activities, including antioxidant, antihyperglycemic, and anti-inflammatory effects in vitro. The phenolic profiles were analyzed using UHPLC-PDA-ESI-MS³, HPLC-PDA, and spectrophotometric methods (total phenolic content, TPC) to understand their seasonal variability and its correlation with bioactive properties. The identified phenolic compounds included caffeic acid derivatives, flavan-3-ols (especially (−)-epicatechin and procyanidins B-type), and flavonoids like quercetin mono- and diglycosides. Leaves harvested in July and October contained the highest polyphenolic levels and demonstrated significant antioxidant activity in most tests. The leaves harvested in July, September, and October showed optimal anti-inflammatory effects, whereas the highest antihyperglycemic activity was observed in the leaves collected from June to July. Regarding polyphenolic levels and bioactivity, the summer and autumn months appear to be the most advantageous for harvesting leaf material of optimal quality for phytotherapy. Full article

The aim of this study was to investigate the qualitative and quantitative fruit profiles of ten cultivars (cvs.) of haskap berry (Lonicera caerulea var. kamtschatica Sevast.) to determine their antioxidant activity (ABTS test, CUPRAC test, ability to capture superoxide (O₂˙⁻) and hydroxyl radicals (OH˙)), cytotoxic activity (against cancer cell lines breast, MCF-7; colon, HT-29; and melanoma, SK-Mel-28) and physicochemical properties. Most of the selected cultivars had not previously been analyzed for these properties. A total of 19 polyphenolic compounds were identified in the fruits of the tested genotypes, with a quantitative range of 2166.3–3597.0 µg/g. The polyphenol profile was dominated by anthocyanins (90.0–92.4%), and the remaining classes occurred in the following order: phenolic acids > flavonols > flavan-3-ols. The highest concentrations of these polyphenol groups were found in the cultivars ‘Honeybee’, ‘Sinij Uties’ and ‘Usłada’. The fruits of these cultivars were also characterized by the highest antioxidant activity (546.6–683.5 µg/mL for O₂˙⁻ and 541.2–652.1 µg/mL for OH˙) and cytotoxic activity (103.6–649.2 µg/mL). The data obtained indicate that the fruits of the new haskap cultivars are a good source of bioactive compounds with possible health-promoting properties. Full article

This study presents the metabolomic profiles of the four Ribes species (Ribes pauciflorum Turcz., Ribes triste Pall., Ribes dicuscha Fisch., and Ribes aureum Purch.). The plant material was collected during two expeditions in the Russian Far East. Tandem mass spectrometry was used to detect target analytes. A total of 205 bioactive compounds (155 compounds from polyphenol group and 50 compounds from other chemical groups) were tentatively identified from the berries and extracts of the four Ribes species. For the first time, 29 chemical constituents from the polyphenol group were tentatively identified in the genus Ribes. The newly identified polyphenols include flavones, flavonols, flavan-3-ols, lignans, coumarins, stilbenes, and others. The other newly detected compounds in Ribes species are the naphthoquinone group (1,8-dihydroxy-anthraquinone, 1,3,6,8-tetrahydroxy-9(10H)-anthracenone, 8,8′-dihydroxy-2,2′-binaphthalene-1,1′,4,4′-tetrone, etc.), polyhydroxycarboxylic acids, omega-3 fatty acids (stearidonic acid, linolenic acid), and others. Our results imply that Ribes species are rich in polyphenols, especially flavanols, anthocyanins, flavones, and flavan-3-ols. These results indicate the utility of Ribes species for the health and pharmaceutical industry. Full article

The goal of the research was to determine the impact of fortification with polyphenolic compounds on (i) sensory attractiveness (global satisfaction, appearance, colour, odour, flavour, sweetness, bitterness), (ii) content of polyphenols and colour (L*, a*, b*) after the baking process and (iii) their bioactive potential (antioxidants activity and inhibiting of α-amylase and α-glucosidase enzyme). Fortification was made with extracts of polyphenolic compounds of selected plant raw materials rich in polyphenols from quince (fruits), tilia (flowers), pomegranate (skin), passion fruit (endocarp), sour cherries (leaves), haskap and chokeberry (berries), silver skin (coffee beans), rosehip (seeds). Depending on the nature of the polyphenol extract, flavan-3-ols (monomeric and polymeric), phenolic acid, flavonols and anthocyanins were identified in the product in amounts ranging from 53.7 to 212.6 mg/100 g DM. Cookies’ colour (L*, a*, b*) depended on the type of polyphenol extract used for fortification. Cookies with haskap, chokeberry and sour cherry presented the highest antioxidant potential. Cookies with chokeberry, haskap and rosehip presented high activity in inhibiting α-amylase (65.5, 60.6 and 62.2% of inhibition, respectively), but cookies with haskap, silver skin and quince in inhibiting α-glucosidase activity (23.0, 20.4 and 21.4% of inhibition, respectively). In the sensory evaluation, the most attractive were cookies with rosehip and pomegranate (6.3 and 5.8 score, respectively), but the lowest ratings were given to cookies with passion fruit and silver skin but especially quince cookies, which obtained the lowest desirability (3.7 score). The acceptability of fortified cookies was determined to the least extent by monomeric flavan-3-ols and phenolic acids (in minus in odour/flavour, bitterness, sweetness and global satisfaction), but anthocyanins, polymeric procyanidins and flavonols had the most significant positive impact on consumer acceptance of the assessed features, i.e., global satisfaction, odour/flavour, sweetness and bitterness (positive consumer drivers). Full article

The aim of this study was to produce and to characterize craft beer fermented by immobilized yeast cells with the addition of Prokupac grape pomace seed powder (2.5% and 5%), to obtain a beer enriched with phenolic compounds and improved sensory characteristics. The immobilization of the yeast cells was performed by electrostatic extrusion, while the obtained calcium alginate beads were characterized by light and scanning electron microscopy. Phenolic and hop-derived bitter compounds in beer with or without grape pomace seed powder (GS) phenolics were identified using UHPLC Q-ToF MS. The results indicated that GS adjunct significantly shortened the fermentation process of wort and increased the content of phenolic compounds, especially ellagic acid, flavan-3-ols and pro(antho)cyanidins in the final products compared to the control beer. A total of twenty (iso)-α-acids and one prenylflavonoid were identified, although their levels were significantly lower in beers with GS phenolics compared to the control beer. Beers with GS phenolics showed good antioxidant properties as measured by the reduction of ferric ions (FRP) and the scavenging of ABTS^•+ and DPPH^• radicals. The concentration of immobilized viable yeast cells was higher than 1 × 10⁸ CFU/g wet mass after each fermentation without destroying the beads, indicating that they can be reused for the repeated fermentation of wort. Beers produced with 5% GS added to the wort exhibited the best sensory properties (acidity, astringency, bitterness intensity, mouthfeel, aftertaste and taste), and highest overall acceptability by the panelists. The results showed that grape pomace seed powder present a promising adjunct for the production of innovative craft beer with good sensory properties and improved functionality. Full article

Cocoa flavan-3-ols affect endothelium-dependent responses in resistance vessels and microcirculation has received little attention. We tested the effects of dark chocolate consumption (396 mg total flavanols/day for 3 days) in two Groups of 10 men (18–25 years; non-smokers) each comprising equal numbers of White European (WE) and South Asian (SA) ethnicity. In Group 1, dark chocolate did not affect reactive hyperaemia in forearm muscle, but augmented muscle dilatation evoked by acute mental stress, and reactive hyperaemia and acetylcholine (ACh)-evoked dilatation in cutaneous microcirculation. Conversely, in Group 2, chocolate did not affect cutaneous reactive hyperaemia or ACh-evoked dilatation, but these responses were blunted in Group 1 relative to Group 2. Further, when Groups 1 and 2 were combined, responses were blunted in SAs relative to WEs, augmented by chocolate in SAs only. In Group 2 individuals whose ACh-evoked dilatation was attenuated by nitric oxide synthase (NOS) inhibition, ACh-evoked dilatation was not altered after chocolate, but the attenuating effect of NOS inhibition was lost. Conversely, in Group 2 individuals whose ACh-evoked dilatation was enhanced by NOS inhibition, ACh-evoked dilatation was also augmented by chocolate. We propose that in resistance and microvessels of young men, cocoa flavan-3-ols preferentially augment endothelium-dependent dilator responses whose responses are depressed by familial and lifestyle factors more prevalent in SAs than Wes. Flavan-3-ols may facilitate the NOS pathway but also influence other endothelium-dependent dilators. Full article

Pomace is a by-product resulting from the pressing of fruits and vegetables into juices, and it is typically treated as waste. Interestingly, pomace contains minimal amounts of protein and fat but is characterized by its high polyphenol and dietary fiber contents, which may have health benefits for human physiology. Therefore, they are a potentially attractive raw material for the food industry, but to our knowledge, no smoothies with their addition have been prepared and described so far. Consequently, products derived from apple juice, incorporating different doses of fresh (6% and 12%) and dried (3% and 6%) black or red currant pomace, were formulated, and their physical properties, chemical composition, bioactive compound content, and health-promoting potential (in vitro antioxidant and antidiabetic activity) were evaluated. Additionally, the products underwent sensory assessment by consumers. The fortified beverages exhibited different physical characteristics and chemical compositions than apple juice. All smoothies were characterized by higher concentrations of anthocyanins, flavonols, and procyanidin polymers compared to the base product. Moreover, 75% of them exhibited a significantly elevated phenolic acid content as well as a higher concentration of flavan-3-ols. The majority of fresh smoothies exhibited significantly higher in vitro antioxidant capacities and increased in vitro α-amylase and α-glucosidase inhibitory effects compared to the base product. The highest ABTS activity was recorded in the variant with 6% dried black currant pomace. In turn, the smoothie with 3% dried red currant pomace had the most effective FRAP effect and, together with the product containing 12% fresh black currant pomace, ORAC antioxidant activity and α-glucosidase inhibition also. The introduction of 6% dried red currant pomace led to the creation of a beverage that most effectively inhibited α-glucosidase. The study showed that the application of various types of pomace, mainly that of black currant, into apple juice enables the development of new functional products with sensory attributes that are favorably evaluated by consumers. Full article

Asynchronous ripening is a significant challenge in winemaking. Green berries reduce alcohol and pH while increasing acidity. Green berries are rich in bitter and astringent compounds, with an unknown impact on wine quality. The aim of this study was to evaluate the impact of harvest date and vineyard location on the polyphenolic composition of Plavac Mali wines in Dalmatia, Croatia. Experiments were conducted in two locations, Split and Zadar, producing fifteen wines per location from four harvest dates (H1–H4), including green berry wines from H1. The first harvest date occurred 27 days after véraison (DAV) and the last at 69 DAV, corresponding to overripeness. Green berry wines of H1 had low alcohol content up to 4.4% (v/v) in Split. Epigallocatechin was the main flavonoid in those wines, followed by dimer B1 in Split and catechin in Zadar. Green wines from Split had a higher concentration of phenolic acids, flavan-3-ol monomers and dimers. Wines of H3 had the highest concentration of malvidin-3-O-glucoside. With a later harvest date, a dramatic decrease in catechin and dimers was observed in wines from Split, and a decrease in epicatechin, epigallocatechin and dimer B1 in those from Zadar. The final expression of the physiochemical and polyphenolic composition of Plavac Mali wine is determined by the dynamics of harvest date, location and their interactions. Full article