Search Results (70)

Postbiotics are bioactive microbial metabolites recognized for their potential to support skin health and balance the microbiota. In this study, nonwoven fabrics and adult diaper prototypes, with and without postbiotic incorporation, were evaluated for their effects on skin microbiota, epidermal integrity, and cytotoxicity. In vitro assays using reconstructed human epidermis and keratinocyte cell lines demonstrated that postbiotic-containing samples maintained high tissue and cell viability. Microbiota diversity analyses confirmed that postbiotic formulations maintained a favorable ratio of Staphylococcus epidermidis to Staphylococcus aureus. Collectively, these findings indicate that ATA-coded postbiotic-embedded nonwoven and adult diaper prototypes are skin microbiota-friendly, safe for epidermal contact, and stable in their bioactive compound content. These results underscore the potential of postbiotics as functional agents in personal hygiene products to promote skin health. Full article

Natural Deep Eutectic Solvents (NADES) were synthesized from food-grade components and evaluated as green extractants for the simultaneous recovery and liquid chromatography coupled to quadrupole-Orbitrap mass spectrometry (LC–Q-Orbitrap-MS) analysis of biopesticide residues in a complex matrix like honey. Conventional solid–liquid extraction (SLE) was applied, initially using choline chloride-2,3-butanediol (1:4, molar ratio) as the NADES extractant solvent, before systematically evaluating other NADES formulations. Extraction parameters, such as time (10 min, 20 min, and 30 min), technique (rotary mixing vs. sonication), and NADES composition, namely lactic acid–glucose–water (LGH, 5:1:9, molar ratio), lactic acid–glycerol–water (LGLH, 1:1:3, molar ratio), urea–glycerol–water (UGLH, 1:1:2, molar ratio), and choline chloride–2,3-butanediol (ChClBt, 1:4, molar ratio), were systematically optimized. Rotating agitation for 10 min yielded the highest overall recoveries and was therefore selected as the optimal extraction time. Rotary shaking was chosen over sonication due to its superior performance across both simple and complex matrices. Among the NADES tested, UGLH proved to be the most effective composition for the honey matrix. The analytical method was validated for the honey matrix. Linearity showed excellent performance across the tested concentration range, with R² values above 0.95 for all analytes. Matrix effects were within ±20% for nearly half of the compounds, while a few exhibited moderate matrix enhancement. Recoveries ranged from 50.1% to 120.5% at 500 µg/kg and 1000 µg/kg, demonstrating acceptable extraction performance. Intra-day and inter-day precision showed relative standard deviations (RSDs) below 20% for most analytes. Limits of quantification (LOQs) were established at 500 µg/kg for eight compounds based on recovery and precision criteria. These results confirm the suitability of the proposed NADES-based method for sensitive and reliable analysis of biopesticide residues in honey. When compared to conventional extraction methods, the proposed NADES-based protocol proved to be a greener alternative, achieving the highest AGREEprep score due to its use of non-toxic solvents, lower waste generation, and overall sustainability. Full article

Exopolysaccharides (EPSs) produced by lactic acid bacteria (LAB) have received special attention as valuable products due to their potential applications as techno-functional and bioactive ingredients in foods. EPS production and consumption are an age-old practice in humans, as evidenced by fermented foods. Over the last two decades, extensive research has examined, analyzed, and reported a wide variety of EPSs from several LAB strains, as well as their techno-functional properties in foods. Also, research efforts focused on EPS characterization and yield production have been carried out. In food applications, EPS quantification and characterization in situ (direct fermentation) took place in various matrices (dairy, bread, plant-based fermented, and meat products). EPS direct application (ex situ) has been less investigated despite its better structural–functional control and use in non-fermented foods. Fewer EPS investigations have been conducted related to health benefits in humans and their mechanisms of action. The composition and functionality of EPSs vary depending on the LAB strain and food matrix used to produce them; thus, various challenges should be addressed before industrial applications are performed. This review aims to compile and summarize the recent findings on EPSs produced by LAB, highlighting their yield, culture production, techno-functional role in foods, food applications, and health benefits in clinical trials. It examines their dual applications, whether as purified functional ingredients (ex situ) or as fermentation products (in situ), and critically assesses both technological and bioactive implications. Also, it explores production challenges, regulatory considerations, and future perspectives for sustainable and tailored applications of EPSs in food innovation. Full article

Background and Objectives: Feces-induced peritonitis (FIP), a clinically relevant model of polymicrobial sepsis, induces systemic inflammation and acute lung injury (ALI). Methylene blue (MB), a phenothiazine-based compound, exhibits vasoregulatory, antioxidant, and anti-inflammatory properties in the context of sepsis. This study aimed to evaluate the protective effects of MB on pulmonary injury in a rat model of FIP-induced sepsis. Materials and Methods: Forty male Wistar rats were randomly assigned to four groups: control, FIP, FIP + Saline, and FIP + MB. MB was administered intraperitoneally at a dose of 20 mg/kg, 1 h after FIP induction. At 24 h post-induction, plasma levels of inflammatory markers [interleukin-6 (IL-6), interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP)], oxidative stress marker [malondialdehyde (MDA)], metabolic indicator [lactic acid], and vascular signaling marker [cyclic guanosine monophosphate (cGMP)] were measured. Lung injury was evaluated through histopathological analysis and thoracic computed tomography (CT)-based Hounsfield unit (HU) quantification, while pulmonary function was assessed via arterial blood gas analysis, including arterial oxygen pressure (PaO₂) and carbon dioxide pressure (PaCO₂). Results: FIP induction led to significant increases in plasma levels of IL-6, IL-1β, TNF-α, CRP, MDA, cGMP, and lactic acid, accompanied by elevated CT attenuation (HU) values and a marked reduction in arterial PaO₂ and PaCO₂. MB treatment significantly decreased the levels of IL-6, IL-1β, TNF-α, CRP, MDA, lactic acid, and cGMP, improved PaO₂, and attenuated both histopathological lung injury and CT-assessed parenchymal density. No significant differences were observed in PaCO₂ among the groups. Conclusions: MB mitigates inflammation, oxidative damage, and pulmonary dysfunction in FIP-induced sepsis. Further studies are warranted to optimize dosing and timing and to evaluate long-term outcomes. Full article

Combining advanced extraction technologies with non-pollutant solvents represents a sustainable approach toward valorizing medicinal plants and aligns with the principles of green chemistry. This study aimed to evaluate the efficiency of microwave-assisted extraction (MAE) combined with natural deep eutectic solvents (NADES) to extract bioactive compounds from the underexplored leaves and bark of Salix amplexicaulis Bory & Chaub. Additionally, the potential of NADES as sustainable alternatives to conventional solvents was assessed through a comparative evaluation of MAE-NADES with MAE–water and traditional ethanol maceration. NADES based on lactic acid–glycerol, lactic acid–glucose, glycerol–glucose, and glycerol–urea were synthesized by heating and stirring. Willow extracts were characterized by HPLC-DAD, resulting in the identification and quantification of seven phenolic acids and four flavonoids. Lactic acid–glucose (5:1)-based NADES extracted the highest number of phenolics in the greatest amount from the bark and leaves of S. amplexicaulis. MAE-NADES offers a fast, cost-effective preparation, high extraction efficiency, and environmentally friendly properties, opening new perspectives on the valorization of S. amplexicaulis in the pharmaceutical field. Furthermore, NADES provide a promising alternative to water and toxic organic solvents for extracting bioactives. Full article

Drug delivery systems have revolutionized the clinical field by enabling the targeted, controlled, and sustained release of therapeutic agents, minimizing side effects and maximizing efficacy. Among the various drug delivery platforms, polymer-based systems have gained significant attention due to their versatility and biocompatibility. This study investigates the release of dexamethasone and clobetasol propionate from PLA (poly(lactic acid)) fibers in a cellular culture system. The release profiles were analyzed over 1, 6, and 24 h using high-performance liquid chromatography (HPLC), showing a gradual, continuous release, with clobetasol exhibiting slower release due to its poor water solubility. The presence of fibroblasts did not significantly affect the drug release, and the concentrations increased over time. An intracellular recovery test revealed that both drugs entered the cells, although their concentrations were below the limit of quantification (LOQ). Measurements of the remaining drug in the fibers confirmed a sustained release, with no significant difference between conditions with and without cells. These results highlight the potential of PLA fibrous membranes for controlled drug delivery, though further research is needed to optimize release and improve intracellular quantification for more effective therapeutic applications. Full article

A biosensor for the determination of glucose, lactate, ethanol and starch in beverages has been developed using enzymes immobilized by a redox-active gel on a screen-printed electrode. A significant improvement proposed for multichannel biosensors, overcoming stability and sensitivity issues by covalently binding phenazine mediators to a biocompatible protein hydrogel, enhancing the packaging of the enzyme. Glucose oxidase (GOx), alcohol oxidase (AOx) and lactate oxidase (LOx) were used as biological materials, as well as a mixture of GOx with γ-amylase (Am). Redox gels were synthesized from bovine serum albumin (BSA) and phenazine derivatives. It was shown that a neutral red-based redox gel combined with single-walled carbon nanotubes is more promising than other substrates for enzyme immobilization. The lower limit of quantification for glucose, ethanol, lactate and starch using these systems is 0.035 mM, 2.3 mM, 15 mM and 2 mg/L, respectively. Biosensors were used to analyze the content of these substances in alcoholic, kvass and fermentation mass. Statistical analysis of the results showed that the values of glucose, ethanol, lactic acid and starch determined using biosensors and obtained by reference methods differ insignificantly. A set of biosensors developed on the basis of specifically selected enzymes is effective for controlling biotechnological processes and can be used as an alternative to classical analytical methods. Full article

The spoilage of wine caused by Brettanomyces bruxellensis and Hanseniaspora uvarum poses a significant challenge for winemakers, necessitating the development of effective and reliable strategies to control the growth of these yeasts, such as grape must bioprotection. Despite evidence that certain microorganisms can inhibit the growth of Brettanomyces bruxellensis and Hanseniaspora uvarum, the specific mechanisms driving this inhibition remain unclear. The primary objective of this study is to elucidate the underlying mechanisms responsible for this inhibitory effect. We analyzed one Metschnikowia pulcherrima (Mp2) and two Lachancea thermotolerans (Lt29 and Lt45) strains, all of which demonstrated significant killing and inhibitory effects on Brettanomyces bruxellensis (B1 and B250) and Hanseniaspora uvarum (Hu3137) in synthetic must at pH 3.5 and 22 °C. The effectiveness of these two strains exhibited varying inhibition kinetics. The strains were monitored for growth and metabolite production (L-lactic acid, ethanol, and acetic acid) in both single and co-cultures. The low levels of these metabolites did not account for the observed bioprotective effect, indicating a different mechanism at play, especially given the different growth profiles observed with added L-lactic acid and ethanol compared to direct bioprotectant addition. Following the production, purification, and quantification of killer toxins, different concentrations of toxins were tested, showing that the semi-purified Mp2Kt, Lt29Kt, and Lt45Kt toxins controlled the growth of both spoilage yeasts in a dose-dependent manner. These bioprotectant strains also showed compatibility with Saccharomyces cerevisiae in co-cultures, suggesting their potential use alongside commercial starter cultures. Full article

The increasing pollution and wastage of food and byproducts from agro-industrial production is an increasingly worrying issue. Grape is one of the most diffused fruit crops cultivated, and grape pomace is the main solid byproduct obtained in the winemaking process; interestingly, it is rich in health-beneficial bioactive molecules. In order to recover these molecules, in this work, a green method has been developed, considering two grape pomaces from different cultivars, namely, Petit Verdot and Cabernet Sauvignon. The extraction procedure, as the first step of this process, was carried out with seven selected deep eutectic solvents (DESs). Then, analysis using HPLC-DAD allowed the detection and quantification of eight out of fifteen different phenolic compounds under examination in the extracts produced, including three quercetin glucosides. The evaluation of antioxidant activity, through the DPPH photometric assay, led to the selection of choline chloride/urea 1:2 + 40% water DES extracts as the extracts with the most promising results. Moreover, significant antibacterial activity was also achieved, in particular, for the betaine/lactic acid 1:4 + 40% water DES extract. Further studies will employ this method for numerous cultivars of grape pomaces with the ambitious aim of the production of polyphenol-enriched food and feed supplements. Full article

Folate deficiency is a widespread nutritional issue, and biofortifying dairy products through lactic acid bacteria (LAB) is a promising strategy to enhance natural folate levels. This study aimed to develop a reliable method for selecting Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus strains with enhanced folate production for use as functional starter cultures. Initially, a traditional microbiological assay (MA) was used to measure folate production in 36 LAB strains isolated from fermented milks. Due to MA’s limitations, an untargeted and semi-quantitative method combining ultra-high-performance liquid chromatography (UHPLC) with high-resolution mass spectrometry (HRMS) was developed for a more comprehensive folate screening. The MA showed higher folate production in S. thermophilus strains (309–639 µg/L) compared to L. delbrueckii subsp. bulgaricus (up to 48 µg/L). Subsequently, nine selected LAB strains were further analyzed using the UHPLC-HRMS approach, which enabled the identification and semi-quantification of six folate metabolites, namely dihydrofolate, tetrahydrofolate (THF), 10-formyl-THF, 5,10-methenyl-THF, 5,10-methylene-THF, and 5-methyl-THF. Lab-scale yogurt production using the top-performing strains, as identified through the HRMS method, demonstrated an increase in folate content over a 14-day shelf life. These findings revealed the potential of UHPLC-HRMS as a high-throughput alternative method for folates detection, offering a promising tool for screening folate-enhanced LAB strains for biofortification. Full article

Gamma-aminobutyric acid (GABA) has been attributed to health-promoting properties and has received attention from the food industry as an attractive bioactive compound for the development of functional foods. Some lactic acid bacteria (LAB) produce GABA through a glutamate decarboxylase encoded by gadB and a glutamate/GABA antiporter encoded by gadC. In this study, we develop a molecular screening method based on a polymerase chain reaction able to detect those genes in different LAB species through the use of novel multispecies primers. PCR was performed in 92 LAB strains of six different species. The primer pair designed for gadB allowed its identification in Lactiplantibacillus plantarum, Lactococcus cremoris, Lactococcus lactis, Levilactobacillus brevis, Limosilactobacillus fermentum, and Limosilactobacillus reuteri strains. For gadC, two different primer pairs were designed for its detection in different species. Glutamate decarboxylase activity (GAD assay) and GABase enzymatic quantification were also assessed. Among those strains showing glutamate decarboxylase activity, 93.2% harbored the gadB gene, and those showing GABA production had the gadB gene and exhibited glutamate decarboxylase activity. PCR detection of gadB correlates strongly with GABA production and constitutes a good strategy for the selection of LAB with high yields (>18 mM) that could be used for the development of GABA-enriched functional foods. Full article

Theobroma cacao plantations are of significant economic importance worldwide, primarily for chocolate production. During the harvest and processing of cocoa beans, they are subjected to fermentation either by microorganisms present in the environment (spontaneous fermentation) or the addition of starter cultures, with different strains directly contributing distinct flavor and color characteristics to the beans. In addition to fungi and bacteria, viruses are ubiquitous and can affect the quality of the fermentation process by infecting fermenting organisms, destabilizing microbial diversity, and consequently affecting fermentation quality. Therefore, in this study, we explored publicly available metatranscriptomic libraries of cocoa bean fermentation in Limon Province, Costa Rica, looking for viruses associated with fermenting microorganisms. Libraries were derived from the same sample at different time points: 7, 20, and 68 h of fermentation, corresponding to yeast- and lactic acid bacteria-driven phases. Using a comprehensive pipeline, we identified 68 viral sequences that could be assigned to 62 new viral species and 6 known viruses distributed among at least nine families, with particular abundance of elements from the Lenarviricota phylum. Interestingly, 44 of these sequences were specifically associated with ssRNA phages (Fiersviridae) and mostly fungi-infecting viral families (Botourmiaviridae, Narnaviridae, and Mitoviridae). Of note, viruses from those families show a complex evolutionary relationship, transitioning from infecting bacteria to infecting fungi. We also identified 10 and 3 viruses classified within the Totiviridae and Nodaviridae families, respectively. The quantification of the virus-derived RNAs shows a general pattern of decline, similar to the dynamic profile of some microorganism genera during the fermentation process. Unexpectedly, we identified narnavirus-related elements that showed similarity to segmented viral species. By exploring the molecular characteristics of these viral sequences and applying Hidden Markov Models, we were capable of associating these additional segments with a specific taxon. In summary, our study elucidates the complex virome associated with the microbial consortia engaged in cocoa bean fermentation that could contribute to organism/strain selection, altering metabolite production and, consequently, affecting the sensory characteristics of cocoa beans. Full article

Naturally fermented dairy products are an important component of the human diet. They are a valuable source of nutrients as well as vitamins and minerals. Their importance as a source of probiotic bacterial strains should not be overlooked. A number of studies highlight the positive effects of species of the probiotic lactic acid bacteria on the intestinal microbiome and the overall homeostasis of the body, as well as a complementary treatment for some diseases. However, data on the effects on the intestinal epithelial cells of postmetabolites released by probiotic bacteria are incomplete. This is likely due to the fact that these effects are species- and strain-specific. In the present study, we investigated the effects of postmetabolites produced by a pre-selected candidate probiotic strain Limosilactobacillus fermentum on HT-29 intestinal epithelial cells. Our data showed a pronounced proliferative effect, evaluated by flow cytometry, quantification of the cell population and determination of the mitotic index. This was accompanied by the stabilization of the cell monolayer, measured by an increase in TEER (transepithelial electric resistance) and the reorganization of actin filaments. The data obtained are a clear indication of the positive effects that the products secreted by L. fermentum strain 53 have on intestinal epithelial cells. Full article

The expanding global population has increased the demand for sustainable protein sources, and microbial protein (MP) has emerged as a promising alternative. However, conventional carbon (glucose) and nitrogen (ammonia, urea) sources needed for MP production pose environmental and economic issues. This study aims to produce protein using lignocellulosic biomass (LCB) as a carbon source and the nitrogen fixation ability of Klebsiella oxytoca M5A1 as a nitrogen source. The study investigates the pretreatment of LCB (switchgrass), enzymatic hydrolysis, protein quantification, nitrogen fixation, glucose utilization and organic acids production. K. oxytoca M5A1 harnessed free nitrogen from the atmosphere and used abundant, cheap glucose from LCB to produce MP and organic acids as by-products. Protein production occurred in two phases: first within the initial 8 h and secondly, within the last 16 h. The highest protein concentration was at 40 h, with approximately 683.46 µg/mL protein content. High-performance liquid chromatography system (HPLC) analysis revealed a dynamic profile of glucose utilization and organic acids (Lactic acid, Propionic acid, Acetic acid, and Succinic acid) production. K. oxytoca M5A1 exhibited an early high rate of glucose consumption, and conversion to organic acids, that were later used for second-phase protein production. The acids profile revealed intra-conversion from one acid to another via metabolic pathways (glycolysis and tricarboxylic acid cycle). Overall, leveraging LCB and the nitrogen-fixing ability of K. oxytoca M5A1 for MP production offers an eco-friendly and cost-effective alternative to traditional protein sources, contributing to a sustainable circular economy. Full article

The study examines the integration of postbiotics in food products through the use of attenuated probiotics, specifically lactic acid bacteria (LAB) in bread. Postbiotics, non-viable microorganisms or their metabolites, offer health benefits similar to probiotics without the risks associated with live bacteria. This research evaluates the regulatory aspects and safety of LAB in sourdough bread production, highlighting their historical and significant use in Europe before 1997. The study includes microbial quantification and Next-Generation Sequencing (NGS) to identify LAB in traditional sourdough, comparing them with historical and current EFSA Qualified Presumption of Safety (QPS) lists. Findings show that the LAB present in sourdough have been extensively and safely used in bread making, supporting their classification as non-novel foods under EU regulations. The stability and consistency of LAB metabolites in sourdough bread are also confirmed, ensuring quality and safety in each batch. The study concludes that LAB in sourdough, when inactivated through bread-making processes, are not considered novel foods, aligning with historical, scientific, and regulatory evidence. Full article