Search Results (80)

Objective: This study systematically evaluated the nutritional compositions and bioactive compounds of six unconventional feed resources (Pepper residue (PR), Grape marc (MC), Pepper straw (PS), Lycium barbarum branches and leaves (LBBL), Licorice straw (LS), and Cyperus esculentus leaves (CES)). It also assessed the rumen degradability and rumen fermentation characteristics at different substitution levels through in vitro and in situ methods, to explore their potential application in sheep diets. Methods: Samples were analyzed considering nutrient composition, amino acids, polyunsaturated fatty acids (PUFAs), and bioactive compounds. In situ degradation was measured using rumen-fistulated sheep, and in vitro batch fermentation culture was conducted at varying substitution levels (0–100%) to measure gas production, pH, VFAs, NH₃-N, and microbial crude protein (MCP). Results: The six unconventional feed resources showed significant differences in nutrient composition, bioactive compounds, and fermentation performance. Crude protein (CP) ranged from 4.45% to 15.76%, with LS highest in total amino acids. LBBL contained 4.24 g/kg Lycium barbarum polysaccharides, LS had 9.24 g/kg liquiritin, GM was richest in proanthocyanidins, and PS had more capsaicin than PR. PR exhibited the highest DM degradation (74.77%, p < 0.001), followed by LS; CEL was lowest. PR and LS also had the highest CP degradation. In vitro fermentation revealed significant differences in fermentation characteristics among the six feeds. At 100% replacement, PR and LS exhibited high cumulative gas production, elevated MCP concentrations, and total VFAs of 54.41 and 64.02 mmol/L (p < 0.001), respectively. At 25% replacement, GM and CEL achieved high concentrations of VFAs and maintained MCP levels of 27.84 and 31.57 mg/dL (p < 0.001). PS reached its maximum total VFAs and MCP at 50% replacement, while LBBL reached 64.90 mmol/L total VFAs and 32.63 mg/dL MCP at 75% replacement. Conclusions: Nutrient composition and degradation kinetics varied significantly among substrates. PR had the highest DM degradability, while CEL had the lowest. PR and LS maintained stable fermentation at 100% substitution. GM and CEL were most effective at 25%; PS at 50%; and LBBL at 75% substitution levels. Full article

Microbial enzymes, due to their efficiency, specificity, and sustainability, are central to innovative biotechnological strategies aimed at optimizing industrial processes such as winemaking. In this study, the potential of Aureobasidium pullulans m11-2, a native dimorphic fungus from the wine ecosystem, was evaluated as a source of hydrolytic enzymes capable of degrading grape cell wall polysaccharides. The strain was identified at the molecular level and characterised in terms of its morphology. To maximise enzyme production, various culture media were tested. Among the concentrations tested, the optimal levels of glucose and pectin were 1 g L⁻¹ and 10 g L⁻¹, respectively. The partially constitutive and inducible nature of the various polysaccharidase activities (pectinases, cellulases, and xylanases) was confirmed. The effect of grape skins (a winemaking by-product) on microbial growth and enzyme synthesis was evaluated, achieving a pectinase activity of 0.622 U mL⁻¹ when combined with 1 g L⁻¹ of glucose. Maximum enzyme yields were detected during the exponential growth phase in both citrus pectin and grape skin media, suggesting favorable conditions for continuous bioprocessing. These results confirm that A. pullulans m11-2 is an interesting microbial option for producing polysaccharidases that can be adapted to sustainable production systems. Full article

Grapes are commonly processed into shelf-stable products such as raisins, wine, juice, and syrup-canned syrup goods. During processing, byproducts like skins and seeds are generated, which contain bioactive compounds including polysaccharides and polyphenols that exhibit diverse biological activities. The objective of this work was to thoroughly evaluate the impact of ultrasound technology on both the extraction efficiency and in vitro hypoglycemic activity of the polysaccharides derived from grape skin. The isolation and purification of the polysaccharides were carried out using chromatographic column techniques, and the monosaccharide components were determined through HPLC. The hypoglycemic activity of the polysaccharides from grape skin in vitro was analyzed in vitro considering their inhibitory effects on α-amylase and α-glucosidase. The polysaccharides from grape skins were extracted via an ultrasound-assisted methodology (under the following conditions: 50 °C, 50 min, 20 mL/g ratio, and 210 W), resulting in an 11.82% extraction yield of GSPs. Monosaccharide constituent analysis revealed that GSP-1-1 consisted of galacturonic acid, arabinose, rhamnose, galactose, glucose, glucuronic acid, mannose, and xylose in a molar ratio of 40.26:26.99:13.58:12.2:2.24:1.97:1.63:1.42. In vitro evaluations indicated that both GSP and GSP-1-1 exhibited notable suppression of α-amylase and α-glucosidase activities, two key enzymes in carbohydrate digestion. This dual inhibitory action positions these compounds as potential therapeutic agents for blood glucose management strategies. This work provides a new direction for addressing the byproducts of the grape canning industry and also offers a theoretical basis for the development of functional grape products. Full article

(1) Grape stalks and aquafaba (Aq) from chickpeas are promising agricultural byproducts with potential applications in the development of sustainable biocomposite materials due to their ligno-cellulose and protein content. (2) This study aimed to evaluate the incorporation of Aq and cinnamon essential oil (CEO) into grape stalk-based materials to enhance mechanical properties and prevent microbial contamination. Four formulations were prepared, and their mechanical, physicochemical, and antifungal properties were assessed. (3) The incorporation of CEO significantly reduced water absorption, while formulations containing Aq exhibited the highest mechanical resistance, likely due to synergistic interactions between proteins and polysaccharides that modified the microstructure of cellulose fibers. Scanning electron microscopy (SEM) images supported these findings. Additionally, CEO-treated samples showed resistance to fungal contamination by Botrytis cinerea, unlike untreated samples, which were colonized by the fungus. Biodegradability tests indicated slower degradation for CEO-treated samples (10 weeks) compared to those without CEO (5–7 weeks). (4) The results suggest that the combination of Aq and CEO creates a promising material for use in food packaging, though further research is needed to fully understand the reinforcement mechanisms. Full article

In this study, a new edible gel of Perilla essential oil (PE)/grape seed extract (GSE)–chitosan/gelatin was prepared, and it was applied to the preservation of silver carp. By establishing a fuzzy mathematical model, using a single-factor experiment and Box–Behnken response surface optimization combined with matlab analysis, the optimum preparation conditions of composite gel films were determined: the addition of PE (p < 0.01) was 6.91 μL/mL, the addition of GSE (p < 0.05) was 0.45 mg/mL, and the addition of gelatin (p > 0.05) was 1.63%. Under these conditions, the composite gel films exhibited an excellent water vapor barrier and mechanical properties. Using Fourier-transform infrared spectroscopy (FTIR) analysis, it was found that the addition of PE enhanced or weakened the absorption peaks, indicating the molecular interaction between PE and the substrate. Scanning electron microscopy (SEM) observed that the surfaces of the composite gel films with added PE were smooth, but there were a few pores in the cross-section. X-ray diffraction (XRD) analysis showed that PE had good compatibility with other components. The fresh-keeping experiment showed that the composite gel films could significantly prolong the fresh-keeping period of grass carp. After 10 days of storage at 4 °C, compared with the blank group (without plastic wrap) and the control group (with composite gel film, no PE added), the experimental group (with composite gel films, PE added) showed better fresh-keeping effect in terms of sensory score, moisture content, pH value, TBARS value, and TVB-N value (p < 0.05). Correlation analysis further confirmed the positive effects of composite gel films on water content, pH value, TVB-N, and other quality indexes of silver carp, indicating that the composite gel films will have broad application prospects in the food preservation field. This study provides an innovative basis and theoretical basis for the development and application of natural polysaccharide/protein composite edible film, which is helpful to promote the development of green food-packaging materials. Full article

After the winemaking process, the residues formed are called wine lees, which represent a mixture of autolyzed yeasts deposited at the bottom of wine-storage tanks. Approximately 2.96 million tons of yeast result from the vinification of 49.4 million tons of grapes. The increased costs of removing these by-products from the wine industry, which is no longer required in the production process, offer us the opportunity to capitalize on various bioactive compounds through the circular economy concept and circular process. Wine lees resulting from the large-scale production of wine represent a raw material for the valorization of phenolic compounds, proteins, and polysaccharides, as well as pigments or organic compounds. The substantial nutrient resources available from wine lees are described extensively in this manuscript and range from vitamins, amino acids, and fatty acids to food supplements, edible packaging, or food products such as bakery products. This review article explores the emerging horizons of winery waste utilization, unveiling the abundance of bioactive compounds and their manifold applications across the industrial realm. Full article

Extracting high-quality RNA from grape (Vitis Vinifera) berry skins is challenging due to their high levels of polysaccharides, phenolic compounds, sugars, and organic acids, which can negatively impact RNA purity and yield. Indeed, polyphenols can bind to RNA, polysaccharides may co-precipitate, and sugars and organic acids can interfere with the pH and ionic properties of the extraction buffer. Commercial kits offer a quick extraction method but are often ineffective for grape berry skins. Similarly, protocols that work well for other vegetal tissues are also inefficient and time-consuming for this tissue. To overcome these limitations, we optimized the RNA isolation by adding a sorbitol pre-wash step to both a non-commercial protocol and a commercial kit. Our results show that it significantly improves the RNA yield and quality from grape berry skins, increasing the RNA purity and integrity, as evidenced by higher RIN (RNA Integrity Number) values and better Qubit and Nanodrop measurements. The strategy’s efficacy was further validated through RNA sequencing, yielding high-quality reads with low error rates, suitable for gene expression studies. Thus, incorporating a sorbitol pre-wash step improves the RNA yield and quality from grape berry skins making it suitable for high-throughput sequencing, and provides a reliable tool for advancing grapevine research. Full article

The genera Komagataeibacter and Novacetimonas comprise industrially important species that produce various foods, nanocellulose, acetan-like polysaccharides, enantioselective sugars, and other valuable products. Here, we describe two novel strains, Hr1 and Jurk4, isolated from pear and apple-grape organic vinegars that showed very high (≥99.39%) 16S rRNA gene sequence identities to species of the Komagataeibacter and Novacetimonas genera, respectively. However, analysis of the 16S-23S rRNA gene internal transcribed spacer (ITS) sequences revealed only 92.6% sequence identity between the Hr1 strain and its closest relative, Komagataeibacter sucrofermentans LMG 18788^T, and 93.8% sequence identity between the Jurk4 strain and its closest relative, Novacetimonas cocois JCM 31140^T. Further whole-genome analysis showed for both strains an average nucleotide identity (ANI) below 94% and an in silico DNA–DNA hybridization (dDDH) value of less than 70% to their closest species, supporting their distinction as novel species. The strain Hr1 can be phenotypically differentiated from its closest Komagataeibacter species based on its ability to utilize (NH₄)₂SO₄ as the sole nitrogen source in Asai medium with D-glucose and its inability to grow with 1-propanol as a sole carbon source. The strain Jurk4 can be differentiated from other Novacetimonas type strains based on its ability to produce 5-keto-D-gluconic acid, its growth in a medium with glycerol as the sole carbon source, and its inability to grow in an Asai medium with D-glucose. Both strains produce cellulose and possess clusters for acetane-like polysaccharide production, although of different types, which makes them industrially relevant. Based on these findings, we propose Komagataeibacter piraceti sp. nov. Hr1^T (=ZIM B1167^T = LMG 33628^T) and Novacetimonas labruscae sp. nov. Jurk4^T (=ZIM B1166^T = LMG 33630^T) as two novel members of the acetic acid bacteria group. Full article

The recovery of polysaccharides (PS) from red grape marc and white grape pomace by enzymatic degradation of their cell walls is an interesting green extraction technique that preserves the structure and bioactivity of PS. The type and dose of enzyme, and the liquid/solid (L/S) ratio in PS extraction were studied using four commercial enzymes. Four different doses per enzyme were used, with tartaric acid as solvent and L/S ratios of 1.3/1 and 4/1 for 24 h at 20 °C, compared with a control. The highest dose of enzyme E1, polygalacturonase + pectin lyase + pectin-methyl-esterase (with the highest activity) was the most effective in the degradation of high and medium molecular weight PS. At the lower L/S ratio, the fact that the highest dose of E1 degraded a higher percentage of high and medium molecular weight PS in the marc was explained by the difference in cell wall deconstruction between pomace and marc. The highest total PS purity was achieved in pomace with E1 at the maximum dose in both ratios, and in marc at the 1.3/1 ratio. The extraction efficiency of total PS was low for all enzymes. In the future, extraction with E1 combined with other green extraction techniques will be studied. Full article

Wine lees, the second most significant by-product of winemaking after grape pomace, have received relatively little attention regarding their potential for valorization. Despite their rich content in bioactive components such as β-glucans, industrial utilization faces challenges, particularly due to variability in their composition. This inconsistency impacts the reliability and standardization of final products, limiting broader adoption in industrial applications. β-Glucans are dietary fibers or polysaccharides renowned for their diverse bioactive properties, including immunomodulatory, antioxidant, anti-inflammatory, antitumor, and cholesterol- and glucose-lowering effects. They modulate the immune system by activating Dectin-1 and TLR receptors on immune cells, enhancing phagocytosis, cytokine production, and adaptive immune responses. Their antioxidant activity arises from neutralizing free radicals and reducing oxidative stress, thereby protecting cells and tissues. β-Glucans also exhibit antitumor effects by inhibiting cancer cell growth, inducing apoptosis, and preventing angiogenesis, the formation of new blood vessels essential for tumor development. Additionally, they lower cholesterol and glucose levels by forming a viscous gel in the intestine, which reduces lipid and carbohydrate absorption, improving metabolic health. The biological activity of β-glucans varies with their molecular weight and source, further highlighting their versatility and functional potential. This study investigates how grape variety, vinification technology and extraction methods affect the yield and properties of β-glucans extracted from wine lees. The physico-chemical and mineral composition of different wine lees were analyzed, and two extraction methods of β-glucans from wine lees were tested: acid-base extraction and autolysis. These two methods were also tested under ultrasound-assisted conditions at different frequencies, as well as without the use of ultrasound. The β-glucan yield and properties were evaluated under different conditions. FTIR spectroscopy was used to assess the functional groups and structural characteristics of the β-glucans extracted from the wine lees, helping to confirm their composition and quality. Rheological behavior of the extracted β-glucans was also assessed to understand the impact of extraction method and raw material origin. The findings highlight that vinification technology significantly affects the composition of wine lees, while both the extraction method and yeast origin influence the yield and type of β-glucans obtained. The autolysis method provided higher β-glucan yields (18.95 ± 0.49% to 39.36 ± 0.19%) compared to the acid–base method (3.47 ± 0.66% to 19.76 ± 0.58%). FTIR spectroscopy revealed that the β-glucan extracts contain a variety of glucan and polysaccharide types, with distinct β-glucans (β-1,4, β-1,3, and β-1,6) identified through specific absorption peaks. The rheological behavior of suspensions exhibited pseudoplastic or shear-thinning behavior, where viscosity decreased significantly as shear rate increased. This behavior, observed across all β-glucan extracts, is typical of polymer-containing suspensions. These insights are critical for optimizing β-glucan extraction processes, supporting sustainability efforts and waste valorization in the wine industry. Efficient extraction of β-glucans from natural sources like wine lees offers a promising path toward their industrial application as valuable functional compounds. Full article

Biodegradable films derived from polysaccharides are increasingly considered eco-friendly alternatives to synthetic packaging in the food industry. The study’s purpose was to improve the antimicrobial properties of biopolymer-based films made from starch, chitosan, alginate, and their blends (starch/chitosan and starch/alginate) and to evaluate the effects of modifiers, i.e., plant extracts, plasticizers, cross-linking agents, and nanofillers. Films were prepared via the Solution Casting Method and modified with various plasticizers, calcium chloride, oxidized sucrose, and nanofiber cellulose (NC). Chestnut, nettle, grape, and graviola extracts were tested for antimicrobial activity against Staphylococcus epidermidis, Escherichia coli, and Candida albicans. The film’s mechanical and hydrophilic properties were studied as well. The chestnut extract showed the strongest antimicrobial properties, leading to its incorporation in all the films. The chitosan films displayed better antibacterial activity against Gram-positive than Gram-negative bacteria but were ineffective against C. albicans. NC significantly improved the mechanical and antimicrobial properties of the chitosan films. The alginate films, modified with various plasticizers cross-linked with calcium chloride, demonstrated the highest antimicrobial efficacy against E. coli. The starch films, cross-linked with oxidized sucrose, exhibited slightly lower antimicrobial resistance due to a more compact structure. Films such as ALG6 and ALG5, including plasticizers EPGOS and PGOS, respectively, indicated optimal hydrophilicity and mechanical properties and achieved the best antimicrobial performance against all the investigated microorganisms. All these findings highlight the potential of these biodegradable films for food packaging, offering enhanced antimicrobial activity that prolongs shelf life and reduces spoilage, making them promising candidates for sustainable food preservation. Full article

Grapes, recognized as a nutritionally rich fruit, have been found through extensive research to contain various bioactive components. However, the roles of polysaccharides and their bioactive properties remain unclear. Based on this, in our research, four different grape polysaccharides were obtained using an enzymatic-assisted extraction method. We investigated and compared their physicochemical properties, antioxidant activities, and protective effects on gastric mucosa in mice. The results indicated that the monosaccharide compositions of these specific grape polysaccharides were similar; however, their molar ratios, molecular weights, and morphological characteristics varied. The results of radical scavenging tests revealed that red-fleshed grape polysaccharide (RFP) exhibited superior antioxidant properties. In vivo assessments demonstrated that RFP protects against gastric mucosal injury in mice by inhibiting inflammation and radical generation. Therefore, the polysaccharide from red-fleshed grape holds potential application value in the pharmaceutical and food industries. Full article

In this study, novel functional ZEO-complex gels were prepared using sodium alginate, inulin, grape seed extract (GSE), and Zanthoxylum bungeanum essential oil (ZEO) as the primary raw materials. The effect of the addition of inulin, GSE, and ZEO on water vapor permeability (WVP), tensile strength (TS), and elongation at break (EAB) of ZEO-complex polysaccharide gels was investigated. A comprehensive score (Y) for evaluating the characteristics of ZEO-complex polysaccharide gels was established by principal component analysis. MATLAB analysis and box-Behnken design describe each factor’s four-dimensional and three-dimensional interactions. It was found that Y could reach the maximum value when the ZEO addition was at a moderate level (C = 2%). The optimum preparation process of ZEO-complex polysaccharide gels was as follows: the addition of inulin was at 0.84%, the addition of GSE was at 0.04%, and the addition of ZEO was at 2.0785%; in this way, the Y of ZEO-complex polysaccharide gels reached the maximum (0.82276). Optical scanning and X-ray diffraction tests confirmed that the prepared ZEO-complex gels have a smooth and continuous microstructure, good water insulation, and mechanical properties. The storage test results show that ZEO-complex polysaccharide gels could play a significant role in the storage and fresh-keeping of grass carp, and the physicochemical properties of complex polysaccharide gels were improved by adding ZEO. In addition, according to the correlation of fish index changes during storage, adding ZEO in complex polysaccharide gels was closely correlated with the changes in fish TBARS and TVB-N oxidation decay indices. In conclusion, the ZEO-complex polysaccharide gels prepared in this study had excellent water insulation, mechanical properties, and outstanding fresh-keeping effects on grass carp. Full article

Daily, a lot of food is wasted, and vegetables, fruit, and cereals as well as marine products represent the major sources of unwanted by-products. The sustainability, waste recovery, and revalorization of food by-products have been proposed as the main goals of the so-called circular economy. In fact, food wastes are enriched in by-products endowed with beneficial effects on human health. Grape, olives, vegetables, and rice contain different compounds, such as polyphenols, dietary fibers, polysaccharides, vitamins, and proteins, which exert antioxidant and anti-inflammatory activities, inhibiting pro-oxidant genes and the Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-kβ) pathway, as demonstrated by in vitro and in vivo experiments. Dietary fibers act upon the gut microbiota, expanding beneficial bacteria, which contribute to healthy outcomes. Furthermore, marine foods, even including microalgae, arthropods, and wastes of fish, are rich in carotenoids, polyphenols, polyunsaturated fatty acids, proteins, and chitooligosaccharides, which afford antioxidant and anti-inflammatory protection. The present review will cover the major by-products derived from food wastes, describing the mechanisms of action involved in the antioxidant and anti-inflammatory activities, as well as the modulation of the gut microbiota. The effects of some by-products have also been explored in clinical trials, while others, such as marine by-products, need more investigation for their full exploitation as bioactive compounds in humans. Full article

Cushuro (Nostoc sphaericum) polysaccharide was used to co-microencapsulate sacha inchi oil, natural antioxidant extracts from the oleoresin of charapita chili peppers (Capsicum frutescens L.) and grape orujo (Vitis vinifera L.). Encapsulation efficiency, moisture, particle size, morphology, oxidative stability, shelf-life, solubility, essential fatty acid profile, sterol content and antioxidant capacity were evaluated. The formulations with grape orujo extract showed higher oxidative stability (4908 ± 184 h), antioxidant capacity (4835.33 ± 40.02 µg Trolox/g ms), higher phenolic contents (960.11 ± 53.59 µg AGE/g ms) and a smaller particle size (7.55 µm) than the other formulations, as well as good solubility and a low moisture content. Therefore, grape orujo extracts can be used as natural antioxidants. The fatty acid composition (ω-3) remained quite stable in all the formulations carried out, which also occurred for sterols and tocopherols. In combination with gum arabic, grape orujo extract offered oxidative protection to sacha inchi oil during the first week of storage. Full article