Search Results (73)

Wild fruits are distributed worldwide, but are consumed mainly in developing countries, where they are an important part of the diet. Still, in many other countries, they are consumed only locally. Blackthorn (Prunus spinosa L.) is an underutilized species rich in fibres and phenolic compounds, making it suitable as a potential functional food for supporting human health. Cold (Cw) and hot (Hw) water-extracted (poly)phenolic polysaccharide–protein complexes, differing in carbohydrate, phenolic and protein contents, were isolated from blackthorn fruits and characterized. The complexes exhibited molecular weights of 235,200 g/mol (Cw) and 218,400 g/mol (Hw), and were rich in pectic polymers containing galacturonic acid, arabinose, galactose and rhamnose, indicating a dominance of homogalacturonan (HG) [→4)-α-D-GalA(1→4)-α-D-GalA(1→]n and a low content of RGI [→2)-α-L-Rha(1→4)-α-D-GalA(1→2)-α-L-Rha(1→]n sequences associated with arabinan or arabinogalactan. Minor content of glucan, probably starch-derived, was also solubilized. Pectic polysaccharides were highly esterified and partly acetylated. Pharmacological testing was performed in male Dunkin–Hartley guinea pigs, a model with human-like airway reflexes. Both complexes affected airway defense mechanisms. Particularly, Hw significantly suppressed citric acid-induced cough, similar to codeine, and reduced bronchoconstriction comparably to salbutamol in a dose-dependent manner. These findings support further exploration of Hw as a natural antitussive and bronchodilatory agent. Full article

It has been previously shown that a selenium (Se) nanocomposite (NC) based on the natural polysaccharide arabinogalactan (AG) produced from Siberian larch wood (Larix sibirica Ledeb.), containing 0.000625% of Se, has antibacterial properties against phytopathogens, such as Clavibacter sepedonicus, Pectobacterium carotovorum, and Phytophthora cactorum. The same concentration of Se/AG NC stimulated the growth and development of potato plants in vitro, as well as the formation of their roots, while Se did not accumulate in potato tissues after plant treatment. However, to realize the full potential of Se/AG NC in agriculture for fighting phytopathogens with the aim of developing commercial nanopreparations, additional toxicological studies are needed to fully address their effects. In this study, to assess the environmental risk of using Se/AG NCs, it was applied to a number of bacteria isolated from soil (Escherichia coli, Bacillus cereus, and B. megaterium), water (Micrococcus luteus, B. subtilis, and Sarcina flava), and activated sludge and wastewater of treatment facilities (Serratia marcescens, M. luteus, B. cereus, and Pseudomonas aeruginosa). When studying the antibacterial activity of Se/AG NC against 11 test cultures of bacteria using the agar diffusion method, it was shown that Se/AG NC had a toxic effect only at high concentrations in the range from 40 mg/mL Se/AG NC (1.68 mg/mL Se) to 0.625 mg/mL Se/AG NC (0.026 mg/mL Se) on two types of bacteria M. luteus isolated from the waters of Lake Baikal and B. cereus obtained from activated sludge of treatment facilities. The maximum diameter of the growth inhibition zone of the test cultures after exposure to different concentrations of Se/AG NC was noted for M. luteus (water) and E. coli (soil) at 40 mg/mL − 26.3 and 20.3 mm, respectively. Thus, the negative impact of Se/AG NC on bacteria from different ecological niches was registered only at high concentrations, similar to the predicted concentrations of Se/AG NC in wastewater, which demonstrates the environmental safety of Se/AG NC for use in agriculture. Full article

Bryophytes, or non-vascular plants, provide valuable models for studying plant adaptation to land, as their physiology differs significantly from that of vascular plants. This study examines the cell wall structure of bryophytes, focusing on the tissue-specific distribution of cell wall epitopes in Sphagnum compactum (a peat moss) and Marchantia polymorpha (the model liverwort) using specific stains and immunolabeling techniques. In S. compactum, chlorocysts and hyalocysts exhibit distinct polysaccharide compositions, with methylesterified and demethylesterified homogalacturonans, arabinans, and hemicelluloses contributing to water retention, structural integrity, and photosynthetic efficiency. In contrast, M. polymorpha demonstrates a simpler yet polarized distribution of homogalacturonans, arabinans, mannans, and xyloglucans, with arabinogalactan proteins uniquely localized in rhizoids, improving their flexibility and anchorage to the substrate. Cellulose was uniformly distributed throughout all tissues in both bryophytes, while crystalline cellulose was only faintly observed. These findings highlight how cell wall adaptations contribute to ecological specialization, providing insights into the evolutionary innovations that enable bryophytes to thrive in terrestrial environments. Full article

Background: Inflammatory bowel diseases, such as ulcerative colitis and Crohn’s disease, affect the gastrointestinal tract. Treatment aims to induce remission and relieve symptoms but may fail or cause side effects. Recent studies suggest that natural polysaccharides can reduce inflammation and promote healing. The polysaccharides of the pulp of tamarillo (Solanum betaceum cav.) have shown beneficial effects, but their potential in colitis is still unexplored. Objective: To investigate the effect of polysaccharides from tamarillo pulp in an animal model of ulcerative colitis. Methods: Polysaccharides from tamarillo pulp (STWA) were extracted and tested in female mice (BALB/c) to investigate their effect on dextran sodium sulfate (DSS)-induced ulcerative colitis. Different doses of the polysaccharides were tested (10 mg/kg, 30 mg/kg, and 100 mg/kg). The course of the disease and the weight of the animals were monitored daily. At the end of the experimental protocol, the large intestine was removed and measured. Markers of oxidative stress and inflammation were then analyzed. Histological analysis was performed to assess microscopic changes. Results: Treatment with STWA (100 mg/kg) prevented weight loss in mice with DSS-induced colitis and reduced the disease activity index. The colon length was preserved, and occult blood in the feces was reduced. Treatment with STWA controlled oxidative stress. Glutathione S-transferase (GST) levels increased, while lipid peroxidation decreased. The inflammatory process was reduced, as indicated by the decrease in myeloperoxidase (MPO), N-acetylglucosamine (NAG), and tumor necrosis factor alpha (TNF-α) levels and the increase in interleukin 10 (IL-10) levels. STWA also improved the colon histology, while preserving the colonic epithelium. Conclusions: The results suggest that STWA has protective potential and reduces inflammation in an experimental model of ulcerative colitis in mice. Full article

Arabinoxylan, a key non-starch polysaccharide in wheat bran, significantly influences the quality and health benefits of wheat beer. This study aimed to investigate how wheat bran addition (0–20%) affects water-extracted arabinoxylan (WEAX) content and beer quality in 100% wheat malt beer. The study integrated physicochemical analyses (polysaccharide composition, WEAX molecular weight), process parameters (wort filtration time, foam stability), and sensory evaluation to establish structure–function relationships. Results showed that the WEAX content in beer increased from 1.36 mg/mL in pure malt beer (0% bran) to 2.25 mg/mL with 20% bran addition. Bran addition shortened wort filtration time by 20–45%. The molecular weight of WEAX was mainly 2936–7062 Da, enhancing foam expansion (36.18%) and stability (15.54%) due to elevated polymerization and arabinose-to-xylose (A/X) ratios. WEAX fractions (7062–10,134 Da and 859–2936 Da) correlated positively with beer turbidity and viscosity. Sensory analysis identified 15% bran as optimal for balanced quality. These findings demonstrate that bran addition enhances WEAX content, polymerization, and A/X ratios, improving foam performance, reducing filtration time, and optimizing beer quality without altering arabinogalactan, glucan, or mannose polymer content. Full article

Coffee is one of the most marketable products worldwide but throughout the production chain, many by-products and waste are generated, e.g., spent coffee grounds (SCG). SCG are considered a promising source of polysaccharides. In the present study, the polysaccharides from SCG were recovered through microwave-assisted extraction. Detailed structural analysis showed that SCG were mainly composed of low-branched galactomannan, followed by various lengths and branches of galactan or arabinogalactan chains whose side chains are randomly ended by glucuronic acid. These findings indicate that glucuronic acid remains attached to the arabinogalactan chain even after coffee roasting and brewing. The investigation confirmed that microwave-assisted extraction, as a green extraction technique, is a promising method for preparing polysaccharides with lower molecular weight. This extraction method ensures the recovery of SCG polysaccharides with potential biological activity without destroying the glucuronic acid at the arabinogalactan chains. Full article

As dietary needs shift with the growing and aging population, there is a demand for food products that meet nutritional, safety, and tribological requirements while being cost-effective. Seniors must be given significant consideration in new product development. This study examines consumer preferences for arabinogalactan (AG) and beta-glucan (BG) hydrogels with vanilla and coffee-biscuit flavors, using consumer tests (N = 80) and an online survey (N = 852). It focuses on the gels’ physical properties, such as texture and viscosity, and their impact on sensory perception. The use of two different gel-forming polysaccharides, each with a unique sensory profile, was observed to affect the sensory properties of the resulting gels and subsequently influence product acceptance. This study analyzed preferences across three age groups: young (18–39 years), middle-aged (40–59 years), and older adults (60+ years). The results showed that seniors preferred AG-based gels. Significant attributes such as the intensity of flavor and bitter taste influenced the overall liking of the gels. Texture also notably impacted preferences. The survey findings revealed statistically significant (p < 0.05) differences in preferences between older adults and younger age groups. Tailoring product development and marketing strategies based on age and sensory preferences could enhance consumer acceptance of edible gels. Full article

Coffee brew is a widespread beverage in human diet with several recognized health benefits. However, the relationship between the chemical portfolio of molecules present in coffee and their bioactive functions are still overlooked. One of the compounds most prevalent in coffee brew are soluble fibers, composed by arabinogalactans and galactomannans polysaccharides and melanoidins, which may influence cholesterol metabolism. Arabinogalactans- and galactomannans polysaccharides- rich fractions as well as coffee extracts were shown to decrease cholesterol bioaccessibility due to their capacity to sequester bile salt. Furthermore, coffee extracts with distinct roasting degrees were shown to affect the bioavailability of cholesterol through Caco-2 cell line model, decreasing sterol permeability, which was attributed to an increased sterol precipitation and its deposition on the apical epithelial surface. Arabinogalactans- and melanoidins-rich fractions were also evaluated regarding the outcome of their fermentability. Both fractions decreased the acetate:propionate ratio, which is indicative of a potential HMG-CoA reductase inhibition. Melanoidin-rich fractions were also shown to decrease the conversion of primary to secondary bile salts, the latter of which are known to be more prone to emulsify cholesterol, impacting cholesterol bioaccessibility and bioavailability. This study demonstrates that coffee exhibits cardioprotective properties, suggesting potential for developing functional food ingredients from coffee extracts to combat cardiovascular diseases, which are among the leading causes of death globally. Full article

The widening of possible areas of practical uses for zero-valent tellurium nanoparticles (Te⁰NPs) from biomedicine to optoelectronic and thermoelectric applications determines the actuality of the development of simple and affordable methods for their preparation. Among the existing variety of approaches to the synthesis of Te⁰NPs, special attention should be paid to chemical methods, and especially to “green” approaches, which are based on the use of precursors of tellurium in their powder bulk form and natural galactose-containing polysaccharides—arabinogalactan (Ar-Gal), galactomannan—(GM-dP) and κ-carrageenan (κ-CG) acting as ligands stabilizing the surface of the Te⁰NPs. The use of basic-reduction system “N₂H₄ H₂O-NaOH” for preliminary activation of bulk-Te and Ar-Gal, GM-dP and κ-CG allowed us to obtain in aqueous medium a number of stable nanocomposites consisting of Te⁰NPs stabilized by the polysaccharides’ macromolecules. By varying the precursor ratio, different morphologies of nanoparticles were obtained, ranging from spheres at a polysaccharide/Te ratio of 100:1 to rice-like at a 10:1 ratio. The type (branched, combed, or linear sulfated) of polysaccharide and its molecular weight value determined the size of the nanoparticles. Thus, the galactose-containing polysaccharides that were selected for this study may be promising renewable materials for the production of water-soluble Te⁰NPs with different morphology on this basis. Full article

Arabinogalactan (AG), extracted from larch wood, is a β-1,3-galactan backbone and β-1,6-galactan side chains with attached α-1-arabinofuranosyl and β-1-arabinopyranosyl residues. Although the structural characteristics of arabinogalactan II type have already been studied, its functionalization using 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) oxidation remains a promising avenue. In this study, the oxidation of AG, a neutral polysaccharide, was carried out using the TEMPO/NaBr/NaOCl system, resulting in polyuronides with improved functional properties. The oxidation of AG was controlled by analyzing portions of the reaction mixture using spectrophotometric and titration methods. To determine the effect of the TEMPO/NaBr/NaOCl system, air-dried samples of native and oxidized AG were studied by Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy, as well as by gel permeation chromatography. Compounds that model free (1,1-diphenyl-2-picrylhydrazyl (DPPH)) and hydroxyl radicals (iron(II) sulfate, hydrogen peroxide, and salicylic acid) were used to study the antioxidant properties. It was found that, in oxidized forms of AG, the content of carboxyl groups increases by 0.61 mmol compared to native AG. The transformation of oxidized AG into the H⁺ form using a strong acid cation exchanger leads to an increase in the number of active carboxyl groups to 0.76 mmol. Using FTIR spectroscopy, characteristic absorption bands (1742, 1639, and 1403 cm⁻¹) were established, indicating the occurrence of oxidative processes with a subsequent reduction in the carboxyl group. The functionality of AG was also confirmed by gel permeation chromatography (GPC), which is reflected in an increase in molecular weights (up to 15,700 g/mol). A study of the antioxidant properties of the oxidized and protonated forms of AG show that the obtained antioxidant activity (AOA) values are generally characteristic of polyuronic acids. Therefore, the TEMPO oxidation of AG and other neutral polysaccharides can be considered a promising approach for obtaining compounds with the necessary controlled characteristics. Full article

Carnivorous plants can survive in poor habitats because they have the ability to attract, capture, and digest prey and absorb animal nutrients using modified organs that are equipped with glands. These glands have terminal cells with permeable cuticles. Cuticular discontinuities allow both secretion and endocytosis. In Drosophyllum lusitanicum, these emergences have glandular cells with cuticular discontinuities in the form of cuticular gaps. In this study, we determined whether these specific cuticular discontinuities were permeable enough to antibodies to show the occurrence of the cell wall polymers in the glands. Scanning transmission electron microscopy was used to show the structure of the cuticle. Fluorescence microscopy revealed the localization of the carbohydrate epitopes that are associated with the major cell wall polysaccharides and glycoproteins. We showed that Drosophyllum leaf epidermal cells have a continuous and well-developed cuticle, which helps the plant inhibit water loss and live in a dry environment. The cuticular gaps only partially allow us to study the composition of cell walls in the glands of Drosophyllum. We recoded arabinogalactan proteins, some homogalacturonans, and hemicelluloses. However, antibody penetration was only limited to the cell wall surface. The localization of the wall components in the cell wall ingrowths was missing. The use of enzymatic digestion improves the labeling of hemicelluloses in Drosophyllum glands. Full article

Reared rainbow trout are vulnerable to environmental stressors, in particular seasonal water warming, which affects fish welfare and growth and induces a temperature response, which involves modifications in tissue lipid profiles. Dietary supplements of plant origin, including the studied mix of a flavonoid, dihydroquercetin and a polysaccharide, arabinogalactan (25 and 50 mg per 1 kg of feed, respectively), extracted from larch wood waste, were shown to facilitate stress tolerance in fish and also to be beneficial for the safety of natural ecosystems and the sustainability of aquaculture production. This four-month feeding trial aimed to determine the effects of the supplement on liver and muscle lipid accumulation and the composition in rainbow trout reared under environmental variables. During periods of environmental optimum for trout, a consistent increase in energy lipid stores, particularly triacylglycerols (2.18 vs. 1.49-fold over a growing season), and an overall increase in lipid saturation due to lower levels of PUFAs, such as eicosapentaenoic (20:5n-3), docosahexaenoic (22:6n-3) and arachidonic (20:4n-6) acids, were observed in both control and supplement-fed fish, respectively. However, in fish stressed by an increase in ambient temperature, dietary supplementation with dihydroquercetin and arabinogalactan reduced mortality (3.65 in control vs. 2.88% in supplement-fed fish, p < 0.05) and alleviated the high-temperature-induced inhibition of lipid accumulation. It also stabilised the membrane phospholipid ratio and moderated the fatty acid composition of fish muscle and liver, resulting in higher levels of n-3 PUFAs and their precursors. Thus, the natural compounds tested are beneficial in accelerating fish tolerance to environmental stressors, reducing mortality and thermal response, and moderately improving fillet quality attributes by increasing the protein/lipid ratio and the abundance of fatty acids essential for human nutrition. Full article

Utricularia (bladderworts) are carnivorous plants. They produce small hollow vesicles, which function as suction traps that work underwater and capture fine organisms. Inside the traps, there are numerous glandular trichomes (quadrifids), which take part in the secretion of digestive enzymes, the resorption of released nutrients, and likely the pumping out of water. Due to the extreme specialization of quadrifids, they are an interesting model for studying the cell walls. This aim of the study was to fill in the gap in the literature concerning the immunocytochemistry of quadrifids in the major cell wall polysaccharides and glycoproteins. To do this, the localization of the cell wall components in the quadrifids was performed using whole-mount immunolabeled Utricularia traps. It was observed that only parts (arms) of the terminal cells had enough discontinuous cuticle to be permeable to antibodies. There were different patterns of the cell wall components in the arms of the terminal cells of the quadrifids. The cell walls of the arms were especially rich in low-methyl-esterified homogalacturonan. Moreover, various arabinogalactan proteins also occurred. Cell walls in glandular cells of quadrifids were rich in low-methyl-esterified homogalacturonan; in contrast, in the aquatic carnivorous plant Aldrovanda vesiculosa, cell walls in the glandular cells of digestive glands were poor in low-methyl-esterified homogalacturonan. Arabinogalactan proteins were found in the cell walls of trap gland cells in all studied carnivorous plants: Utricularia, and members of Droseraceae and Drosophyllaceae. Full article

Carnivorous plants are mixotrophs that have developed the ability to lure, trap, and digest small organisms and utilize components of the digested bodies. Leaves of Drosophyllum lusitanicum have two kinds of glands (emergences): stalked mucilage glands and sessile digestive glands. The stalked mucilage glands perform the primary role in prey lure and trapping. Apart from their role in carnivory, they absorb water condensed from oceanic fog; thus, plants can survive in arid conditions. To better understand the function of carnivorous plant emergences, the molecular composition of their cell walls was investigated using immunocytochemical methods. In this research, Drosophyllum lusitanicum was used as a study system to determine whether cell wall immunocytochemistry differs between the mucilage and digestive glands of other carnivorous plant species. Light and electron microscopy were used to observe gland structure. Fluorescence microscopy revealed the localization of carbohydrate epitopes associated with the major cell wall polysaccharides and glycoproteins. The mucilage gland (emergence) consists of a glandular head, a connecting neck zone, and stalk. The gland head is formed by an outer and inner layer of glandular (secretory) cells and supported by a layer of endodermoid (barrier) cells. The endodermoid cells have contact with a core of spongy tracheids with spiral-shaped thickenings. Lateral tracheids are surrounded by epidermal and parenchymal neck cells. Different patterns of cell wall components were found in the various cell types of the glands. Cell walls of glandular cells generally are poor in both low and highly esterified homogalacturonans (HGs) but enriched with hemicelluloses. Cell walls of inner glandular cells are especially rich in arabinogalactan proteins (AGPs). The cell wall ingrowths in glandular cells are significantly enriched with hemicelluloses and AGPs. In the case of cell wall components, the glandular cells of Drosophyllum lusitanicum mucilage glands are similar to the glandular cells of the digestive glands of Aldrovanda vesiculosa and Dionaea muscipula. Full article

Most polymeric materials are synthetic and derived from petroleum, hence they accumulate in landfills or the ocean, and recent studies have focused on alternatives to replace them with biodegradable materials from renewable sources. Biodegradable wastes from food and agroindustry, such as spent coffee grounds (SCGs), are annually discarded on a large scale and are rich in organic compounds, such as polysaccharides, that could be used as precursors to produce films. Around 6.5 million tons of SCGs are discarded every year, generating an environmental problem around the world. Therefore, it was the aim of this work to develop films from the SCGs polysaccharide fraction, which is comprised of cellulose, galactomannans and arabinogalactans. Two types of crosslinking were performed: the first forming coordination bonds of calcium ions with polysaccharides; and the second through covalent bonds with 1,4-phenylenediboronic acid (PDBA). The films with Ca²⁺ ions exhibited a greater barrier to water vapor with a reduction of 44% of water permeability vapor and 26% greater tensile strength than the control film (without crosslinkers). Films crosslinked with PDBA presented 55–81% higher moisture contents, 85–125% greater permeability to water vapor and 67–150% larger elongations at break than the films with Ca²⁺ ions. Film biodegradability was demonstrated to be affected by the crosslinking density, with the higher the crosslinking density, the longer the time for the film to fully biodegrade. The results are promising and suggest that future research should focus on enhancing the properties of these films to expand the range of possible applications. Full article