Search Results (84)

Blackcurrant is a notable superfruit in Europe, and its vitamin C content surpasses the well-known blueberry superfruit. However, due to its short shelf life during storage, consumption is mainly accounted by frozen berries, extracts, and concentrates. This study applied an intensity of 1.2 W/m² UVC with different durations, including control (non-treated), UVC irradiation for 0.5 h (0.5 h treatment), UVC irradiation for 1 h (1 h treatment), and UVC pretreatment for 2 h (2 h treatment) to blackcurrant berries before storage. Fundamental physical (firmness and weight loss) and physicochemical characteristics (SSC, pH, and acids), microbial population changes, total phenolic content, antioxidant capacity, and specific phenolic compound changes were evaluated every five days over a twenty-day storage period. The results indicated that the longer the UVC pretreatment, the lower the water weight losses during storage. Meanwhile, the UVC pretreatment significantly affected the blackcurrant soluble solid content, resulting in higher soluble solid contents detected in the blackcurrants with the higher doses of UVC. For the mold population control, UVC effects were highly correlated with the pretreatment duration. However, UVC did not have a significant influence on the berry pH and acid contents, but the storage length slightly increased the pH and decreased the acids. At the same time, UVC pretreatment did not affect the berry firmness, polyphenols, ascorbic acid content, or antioxidant capacities, which were primarily influenced by the storage duration. The monophenolic compounds detected before and after storage indicated that more than one hour of UVC radiation influenced most of the phenolic contents largely before storage. The UVC pretreatment has also influenced some phenolic compounds. After storage, half an hour of UVC pretreatment increased cyanidin levels, and two hours of UVC pretreatment increased catechin and epicatechin levels. However, most of the compounds remained at similar amounts during storage in each treatment. Further research is needed to improve the UVC radiation time length or intensity or explore other technology combinations to optimize UVC pretreatments for blackcurrant storage. Full article

The present study aimed to identify the active chemical compounds, mainly phenolic acids, of Champia parvula and Moringa oleifera, evaluate the pharmacokinetic properties of their primary compounds, and assess a novel method for the biocontrol of blue mold by evaluating the antifungal activity of both extracts. Gas chromatography (GC) and high-performance liquid chromatography (HPLC) were utilized to identify the active chemical compounds, mainly phenolic acids. GC illustrated the presence of long-chain aliphatic fatty acids like eicosanoic acid with the formation of oct-1-en-3-ol compounds attached. Catechin was the main bioactive component among the several bioactive compounds identified by HPLC analysis, exhibiting favorable pharmacokinetic behavior, including good absorption, distribution, and metabolic stability. According to the findings, both extracts had antifungal activity, but C. parvula extract (100 mg/mL) exhibited the strongest in vitro and in vivo antifungal activity, with the highest percentages of inhibition (disk diffusion method) against Penicillium expansum, Penicillium crustosum, and Talaromyces atroroseus, ranging between 62.67 and 100%. C. parvula extract (100 mg/mL) could fully inhibit the pathogenicity and aggressiveness of the five tested strains in apple fruits (in vivo). In conclusion, the extract from C. parvula and M. oleifera shows potential antifungal properties and a high phytochemical content. Full article

The apple tree (Malus domestica), a member of the Rosaceae family, holds significant economic value but faces postharvest challenges, like blue mold caused by Penicillium expansum and gray mold caused by Botrytis cinerea. While synthetic fungicides are widely used, their limitations highlight the need for sustainable alternatives. This study explores the antifungal properties of extracts from Celtis australis, Olea europea var. sylvestris, Chamaerops humilis, and Asparagus albus against these pathogens. In vitro tests assessed mycelial growth inhibition, whereas in vivo trials consisted of measurement of weight loss, firmness, total soluble solids, titratable acidity, and maturity index. Moreover, the phytochemical traits of the extracts were determined using the Folin–Ciocalteu method and HPLC. The results revealed notable antifungal activity, particularly for Celtis australis extract at a concentration of 300 g L⁻¹, which led to significant mycelial growth inhibition (61% for P. expansum and 41% for B. cinerea), a reduction in diseases’ severity (39% and 50%), and a notable decrease in diseases’ incidence (43% and 48%), respectively. Phytochemical analysis reflected the presence of phenols and flavonoids in the tested extracts. Importantly, the natural treatments helped preserve the apples’ quality during storage. Molecular docking studies further revealed that major compounds in Celtis australis extract inhibit the 14α-demethylase enzyme, a key target in fungal sterols biosynthesis. Full article

This study investigates hazardous emissions from foundry binder systems, comparing organic resins (phenolic urethane, furan, and alkaline-phenolic) and clay-bonded green sand with inorganic alternatives (sodium silicate and geopolymer). The research was conducted at the Fundaciόn Azterlan pilot plant (Spain), involving controlled chamber tests for the production of 60 kg iron alloy castings in 110 kg sand molds. The molds were evaluated under two configurations: homogeneous systems, where both mold and cores were manufactured using the same binder (five trials), and heterogeneous systems, where different binders were used for mold and cores (four trials). Each mold was placed in a metallic box fitted with a lid and an integrated gas extraction duct. The lid remained open during pouring and was closed immediately afterward to enable efficient evacuation of casting gases through the extraction system. Although the box was not completely airtight, it was designed to direct most exhaust gases through the duct. Along the extraction system line, different sampling instruments were strategically located for the precise measurement of contaminants: volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), phenol, multiple forms of particulate matter (including crystalline silica content), and gases produced during pyrolysis. Across the nine trials, inorganic binders demonstrated significant reductions in gas emissions and priority pollutants, achieving decreases of over 90% in BTEX compounds (benzene, toluene, ethylbenzene, and xylene) and over 94% in PAHs compared to organic systems. Gas emissions were also substantially reduced, with CO emissions lowered by over 30%, NO_x by more than 98%, and SO₂ by over 75%. Conducted under the Greencasting LIFE project (LIFE 21 ENV/FI/101074439), this work provides empirical evidence supporting sodium silicate and geopolymer binders as viable, sustainable solutions for minimizing occupational and ecological risks in metal casting processes. Full article

Microalgae are a sustainable source of bioactive compounds and nutrients that do not compete with crops for arable land. Lobosphaera sp. was used to produce biodegradable films. Bioactive compounds, polysaccharides, and proteins were extracted from this microalga. The total phenolic content (TPC) and antioxidant activity (ABTS, DPPH, and ORAC) of the bioactive-rich extract were determined, and its composition was analyzed for phenolics using LC-ESI-QqTOF-HRMS and for lipids using GC-FID. The cytotoxicity of this extract on Caco-2 cells was also assessed. Different types of films were produced based on alginate (2%) (film A) and alginate with polysaccharides-rich (PS-rich) extract (0.5%) (film B); PS-rich extract and bioactive-rich extract (0.25%) (film C); protein-rich (P-rich) extract (0.5%) (film D); and P-rich extract and bioactive-rich extract (film E). The antioxidant activity and physical parameters of the films, such as thickness, color, water vapor permeability, solubility, tensile strength (TS), and elongation at break (EAB), were determined. The TPC of the bioactive-rich extract was 1.07 ± 0.05 mg GAE/100 mg DW, and its antioxidant activity was 2.44 ± 0.27, 1.67 ± 0.15, and 11.90 ± 1.22 µmol TE/100 mg DW for ABTS, DPPH, and ORAC, respectively. The extract showed no cytotoxicity to gut cells at concentrations equal to or below 1.0 mg/mL. Film E obtained the best results for the antioxidant activity, 451.06 ± 14.68 and 212.81 ± 39.12 µM TE/mg film for ABTS and DPPH, respectively. In addition, the films enriched with the bioactive-rich extract (films C and E) presented antimicrobial activity against Listeria monocytogenes. These films controlled the mold and yeast growth in strawberries during a four-day storage at 25 °C. All films were completely soluble in water and hydroethanolic solutions but only partially solubilized in acetic acid (3%). TS and EAB were not significantly different among the films. It was possible to produce biodegradable films using microalga Lobosphaera sp. with good bioactivity and physical characteristics. Full article

This study examines the impact of added elderberry (EDB) extract on the physico-chemical, microbiological, and sensory properties of yogurt over a 21-day storage period. Two separate experiments were conducted: the first focused on testing concentrations of 0.05%, 0.1%, 0.2%, and 0.5% (w/w) EDB extract for impoving antioxidant properties and replacing potassium sorbate, a chemical preservative commonly used in dairy products, while the second aimed to enhance the bioactive compounds’ concentration by adding 0.5% EDB extract, and to assess the effect of a sweetener (agave syrup) on the sensory profile. Both experimental approaches demonstrated a significant increase (p < 0.01) in total phenolic content. In the first experiment, there was approximately 2.6 times more total phenolic content compared to the control (with a maximum of 11.71 mg GAE/100 g for the sample with 0.2% EDB extract), and about 6 times more with the addition of 0.5% EDB extract and agave syrup (with a maximum of 25.29 mg GAE/100 g). Additionally, the IC₅₀ value decreased for all samples with EDB extract, suggesting enhanced antioxidant activity. Specifically, the antioxidant activity was approximately 3.3 times higher for the control for samples obtained from homemade yogurt with EDB extract, and about 8 times higher for samples obtained by adding EDB extract to commercial yogurt, compared to their respective controls. The high stability of bioactive compounds during the storage period highlights the potential of EDB extract as a functional antioxidant ingredient. Microbiological analysis confirmed the safety of the yogurt, with lactic acid and mesophilic bacteria showing stable counts and minimal declines over time. In the first experiment, a reduction of about 2.3 CFU/g was observed from day 0 to day 21 in samples with 0.1% and 0.2% EDB extract, while the control sample showed a reduction of 1.84 CFU/g. However, the control sample recorded the growth of psychrophilic bacteria, yeasts, and molds. In the second experiment, the samples with 0.5% EDB extract showed an average reduction of approximately 0.35 CFU/g, while the control showed a reduction of 0.51 CFU/g, maintaining stable counts and no detectable growth of psychrophilic bacteria, yeasts, molds, or coliforms. Additionally, the inclusion of different concentrations of EDB extract, along with the combination of a higher concentration of EDB extract and agave syrup, improved the yogurt’s sensory attributes, thereby enhancing consumer acceptance. For the first experiment, 68% of the panelists expressed their preference for the samples with EDB extract, and 10% preferred the control sample. In the second experiment, 49% preferred the sample with 0.5% EDB extract and agave syrup, while 23% preferred the control sample. These findings support the integration of EDB extract into yogurt formulations to boost antioxidant properties while preserving microbiological stability. Future research should explore the potential health benefits and long-term effects of these functional dairy products. Full article

Tomato by-products are widely generated during processing, which deserve revalorization due to being rich in bioactive compounds that can be incorporated into novel formulas. This study explores the use of tomato by-products as a source of pigments and antioxidant compounds to develop a seasoned cucumber beverage enriched with encapsulated carotenoids. Extracts from industrial tomato pomace were obtained using ultrasound-assisted extraction (USAE) and accelerated solvent extraction (ASE), and then encapsulated by spray-drying with inulin (I), maltodextrin (M), or a maltodextrin–inulin blend (MI). The powders were added to a cucumber beverage treated with high hydrostatic pressure (HHP) and stored for 28 days at 4 °C. Physicochemical properties, microbial load, carotenoid content (U-HPLC), free phenolic content (FPC), and total antioxidant capacity (TAC) were monitored. Beverage samples with maltodextrin (ASE-M, USAE-M) and the maltodextrin–inulin blend (ASE-MI, USAE-MI) showed superior color stability and pH maintenance. USAE-MI achieved the highest TAC at the end of storage and ensured microbial safety by reducing mesophilic bacteria, molds, and yeast. During storage, FPC declined (to ~3.5–5 mg 100 mL⁻¹), TAC increased (to ~16–20 mg 100 mL⁻¹), and carotenoid was kept stable (~9–13 mg L⁻¹). These results highlight the potential of combining HHP with tomato by-product encapsulates to improve the shelf life, quality, pigment stability, and antioxidant properties of vegetable-based beverages. Full article

Red grapes often suffer from postharvest diseases like blue mold and black mold caused by Penicillium expansum and Aspergillus niger. Biological control using beneficial yeasts and bacteria is an effective method to manage these diseases. Rhodotorula sp. and Bacillus sp. are effective microorganisms for the control of postharvest diseases of red grapes. This study combined two yeast strains (Rhodotorula graminis and Rhodotorula babjevae) and two bacterial strains (Bacillus licheniformis and Bacillus velezensis) to investigate their biological control effects on major postharvest diseases of red grapes and explore the underlying physiological mechanisms. Research showed that compound microorganism W3 outperformed the others; it reduced spore germination and germ tube growth of P. expansum and A. niger, while its volatiles further inhibited pathogen growth. Additionally, the treatment enhanced the antioxidant capacity of grapes and increased resistance to pathogens by boosting peroxidase activities, superoxide dismutase, catalase and ascorbate peroxidase, phenylalanine ammonolyase, and polyphenol oxidase. Furthermore, the combined treatment increased the activity and accumulation of antifungal compounds such as total phenols and flavonoids, thereby improving disease resistance and reducing decay. Therefore, composite microorganisms combining various antagonistic strains may offer a viable substitute for tackling postharvest diseases in red grapes. Full article

Bioactive compounds and organic acids are applied to a wide range of foods against different types of foodborne pathogens. In the present study, carvacrol and thymol (1000 mg/L) were applied in wine-based marinades, alone or in combination with them and in combination with tartaric acid, malic acid, ascorbic acid, citric acid, and acetic acid (in concentration 0.1% w/v), in chicken and beef fillets and their antimicrobial activity, antioxidant capacity, and pH were estimated during refrigerated storage. Likewise, their antimicrobial activity was recorded against Enterobacteriaceae, total mesophilic bacteria, yeasts/molds, and lactic acid bacteria. The outcome demonstrated that both meats kept under similar storage conditions (4 °C/9 days) exhibited lower microbial growth, particularly with Enterobacteriaceae, when treated with wine-based carvacrol—thymol marinades and may extend their shelf-life. This antimicrobial action was more pronounced in the beef samples. The total phenolic content (TPC) and the antioxidant activity of the applied marinades were determined using the Folin−Ciocalteau method and ABTS and DPPH radical scavenging activity methods, respectively. The results revealed that marinades with thymol and/or carvacrol in combination with acetic or ascorbic acid had greater TPC and antioxidant activity. The pH values of the respective marinades applied to both chicken and beef fillets exhibited an upturn during storage. Consequently, these marinades, even at low concentrations, could be used as natural preservatives in meat products. Full article

Prickly pear consumption is increasing across the world due to its rich variety of nutrients and bioactive compounds. Yet, it is a seasonal and highly perishable fruit, and the application of edible coatings emerges as an alternative to extend its shelf life. In this work, the effects of alginate, starch, chitosan, and pectin as coatings on the physicochemical, bioactive, microbiological, and textural properties of two prickly pear varieties (orange and red), kept under refrigeration (5 ± 2 °C) were evaluated for 6 weeks. Coatings proved to be helpful in the maintenance of the fruits’ color and textural properties, especially when pectin was applied. Overall, starch and chitosan can be considered the most effective coatings in preserving the quality of prickly pears among the options studied. A lower weight loss (8–10%) in fruits was achieved when starch and chitosan were applied, while in control fruits (without coating), the loss was 18–23%. Starch and chitosan also contributed to preserving the bioactivity of red fruits and showed good results in the preservation of total phenolic content in the orange fruits. In addition, starch and chitosan coatings also presented the best performance for the reduction of microbial contamination (both yeasts and molds and total mesophilic aerobic microorganisms). These findings highlight the role of edible coatings in preserving prickly pears, for a longer period, meeting consumers’ demand for fresh fruit. Full article

To determine the optimal conditions of pressurized liquid extraction (PLE) and microwave-assisted extraction (MAE) of polyphenols from black chokeberry leaves (BCL), temperature, time and sample-to-solvent ratio (SSR) were varied to obtain maximum polyphenols yield. The extracts were analyzed for total polyphenols (TP) as well as individual ones (UPLC ESI MS²) and antioxidant capacity (FRAP, DPPH and ORAC). Moreover, the biological activity of the selected extracts was additionally determined. The optimal PLE and MAE conditions were 150 °C, 5 min extraction time and SSR 1:30 g/mL (TP 80.0 mg GAE/g dm), and 70 °C, extraction time 5 min and SSR 1:30 g/mL (TP 36.4 mg GAE/g dm), respectively. Both methods yielded similar polyphenol profiles (43 compounds) but differed quantitatively. MAE extracts contained more flavonols and phenolic acids, while PLE extracts had higher procyanidins and flavan-3-ols. Furthermore, the PLE extract exhibited a superior antioxidant capacity. This BCL extract also showed that it can protect against oxidative and DNA damage and can induce free radical formation and DNA damage, albeit at different doses. Moreover, it had a moderate antimicrobial activity against S. aureus and B. subtilis, while no antimicrobial activity was observed against Gram-negative bacteria as well as yeasts, lactic acid bacteria and molds. Full article

Green mold caused by Penicillium digitatum is a major post-harvest disease in citrus fruits. Therefore, the search for sustainable and low-environmental-impact alternatives for the management of these fungi is of utmost importance. Physalis peruviana L. is a native fruit of the Peruvian Andes with rich bioactive components present throughout the plant. Its antifungal activity stands out, attributed to its high content of phenols, coupled with its antioxidant capacity and antimicrobial activity. Plants were cultivated aeroponically under a combination of red, mixed (50% red, 50% blue), and green LED lights. Additionally, in vitro-habituated roots free of plant growth regulators were also cultivated. An ethanol extraction assisted by ultrasound for 30 min followed by maceration for 72 h was performed, and the extract was filtrated and evaporated in an extraction hood. Antioxidant activity was assessed using the DPPH method, total polyphenols were measured using the Folin–Ciocâlteu method, and an antifungal test in vitro by the poisoned food method was conducted against P. digitatum. In vitro assays revealed that extracts from leaves, roots, and fruits exerted a significant inhibitory effect on the growth of P. digitatum, as evidenced by a reduction in colony radius when cultured employing the poisoned food method, with IC₅₀ values of 62.17, 53.15, and 286.34 µg·mL⁻¹, respectively, compared to 2297 µg·mL⁻¹ for the commercial fungicide Captan 50WP. Although leaves had higher total polyphenol content, no direct correlation with antifungal activity was found. Colored LEDs enhanced phenol accumulation, antioxidant capacity, and antifungal properties in plant parts compared to white LEDs and in vitro roots. These findings suggest P. peruviana as a new alternative biological production system to provide natural compounds for post-harvest disease management. Full article

Fruit mousses, as low-processed products, are highly susceptible to external conditions, and storage leads to the degradation of bioactive compounds, particularly phenolic compounds and vitamins, as well as promoting the growth of yeasts and molds. This study investigated the impact of storage conditions on the microbiological quality and degradation of selected bioactive compounds in fruit mousses from various producers (from apples, pears, and multi-components). Total phenolic (TPC) and total flavonoid (TFC) contents, vitamin C level, antioxidant capacity (AC, measured by the DPPH assay), and concentrations of macro- and microminerals were evaluated in fresh mousses and those stored for 48 h at 23 °C and 4 °C. Changes in total aerobic mesophilic bacteria (TAMB), yeast and mold counts, and selected microbial groups were also checked. It was found that the analyzed compounds varied depending on the components of the mousses. Multi-component mousses contained the highest levels of TPC, TFC, and vitamin C, and had 2–5 times higher AC values compared to apple and pear mousses. Storage at room temperature resulted in TFC lowering of up to 25% in apple mousses and vitamin C reductions of up to 22% in multi-component mousses. During refrigerated storage, the highest losses were observed in pear mousses, with TPC decreasing by up to 13% and vitamin C by up to 11%. Among the minerals, magnesium and zinc levels decreased most significantly in apple mousses stored at 23 °C (up to 33% and up to 29%, respectively). Microbiological analysis revealed variability in TAMB, yeast, and mold counts, with refrigeration (4 °C) generally limiting microbial growth compared to room temperature (23 °C). Notably, no pathogenic bacteria were detected under any storage conditions, and the mousses retained a high microbiological quality even after room-temperature storage. Full article

Pigmented rice grass juice (RGJ) is a good source of bioactive compounds, but fresh juice has a relatively short shelf life of only 7 days at 4 °C. The objectives of this study were to determine the optimal growth stage of pigmented rice grass, investigate the optimal condition of high-pressure processing (HPP) for bacterial inactivation in inoculated RGJ using response surface methodology (RSM), and evaluate quality changes in uninoculated HPP-treated juice during storage at 4 °C compared with heat-treated (85 °C/10 min) and untreated samples. Results revealed that the optimal growth stage of rice grass was 9 days with the highest total anthocyanin content of 158.92 mg/L. The optimal condition of HPP was determined to be 612 MPa, 11 min, and 36 °C, and inactivated Escherichia coli K12 and Listeria innocua with 6.43 and 5.02 log reductions, respectively, meeting FDA regulations. The lethality of bacteria after HPP treatment can be explained by damage to the cell membrane and the leakage of intracellular constituents such as protein and nucleic acid. During 12 weeks of storage at 4 °C, total plate counts and yeast and mold counts in uninoculated HPP-treated juice were not detected. Moreover, HPP did not significantly change phytochemical properties (p < 0.05), caused a minor impact on physicochemical properties of RGJ, and maintained the durability of juice samples during storage. Analysis of the phytochemical profile revealed that HPP treatment could preserve most of the phenolic compounds in RGJ and especially increase the contents of protocatechuic acid, 4-hydroxybenzoic acid, syringic acid, transcinnamic acid, isorhamnetin-3-o-glucoside, quercetin, and cyanidin-3-glucoside (p < 0.05). Overall, HPP is a potential pasteurization technique for microbial inactivation and nutritional preservation for rice grass juice. Full article

Grapes are susceptible to mold and decay during postharvest storage, and developing new technologies to extend their storage period has important application value. Photodynamic technology (PDT) in concurrence with carbon dots (CDs) proposes an innovative and eco-friendly preservation strategy. We examined the effects of carbon dots combined with photodynamic treatment on postharvest senescence and antioxidant system of table grape. The compounding of photodynamic technology with a 0.06 g L⁻¹ CDs solution could possibly extend the postharvest storage period of grape berries. Through this strategy, we achieved a decreased rate of fruit rotting and weight loss alongside the delayed deterioration of fruit firmness, soluble solids, and titratable acid. As paired with photodynamic technology, CDs considerably decreased the postharvest storage loss of phenols, flavonoids, and reducing sugars as compared to the control group. Concurrently, it remarkably postponed the build-up of hydrogen peroxide (H₂O₂), superoxide anion (O₂^∙−), and malondialdehyde (MDA); elevated the levels of reduced ascorbic acid (AsA) and reduced glutathione (GSH); lowered the levels of dehydroascorbic acid (DHA) and oxidized glutathione (GSSG); raised the ratios of AsA/DHA and GSSH/GSSG; encouraged the activities of superoxide dismutase (SOD) and phenylalanine ammonia-lyase (PAL); and inhibited the activities of polyphenol oxidase (PPO) and lipoxygenase (LOX). Furthermore, it enhanced the iron reduction antioxidant capacity (FRAP) and DPPH radical scavenging capacity of grape berries. CDs combined with photodynamic treatment could efficiently lessen postharvest senescence and decay of grape berry while extending the storage time. Full article