Search Results (1,186)

In recent years, great attention has been paid to second-generation (from agricultural and industrial wastes) lactic acid (LA) production. In the present study, the possibility of two Lactiplantibacillus plantarum strains, namely 53 and 2HS, to produce LA from waste materials was investigated. Distiller’s dried grains with solubles (DDGS), spent coffee grounds (SCG), wood chips, and cheese whey were used as substrates after pretreatment, and the results were compared with those with lactose as a carbon source. Both strains were capable of assimilating sugars from all waste materials. Nearly 20 g/L LA from 23 g/L reducing sugars (RS) obtained from DDGS, 22 g/L LA from 21 g/L RS from SCG, and 22 g/L LA from 21 g/L whey lactose were produced compared to 22 g/L LA obtained from 22 g/L lactose monohydrate in the fermentation broth. The wood chip hydrolysate (WH) contains only 10 g/L RS, and its fermentation resulted in the production of 5 g/L LA. This amount is twice as low as that produced from 11 g/L lactose monohydrate. A mathematical model was constructed based on the Compertz and Luedeking–Piret equations. Full article

The transition to sustainable energy sources has intensified interest in lignocellulosic biomass (LCB) as a feedstock for second-generation biofuels. However, the inherent structural recalcitrance of LCB requires the utilization of an effective pretreatment to enhance enzymatic hydrolysis and subsequent fermentation yields. This manuscript presents a novel, single-step, and optimized nitrogen explosive decompression system (NED 3.0) designed to address the critical limitations of earlier NED versions by enabling the in situ removal of inhibitory compounds from biomass slurry and fermentation inefficiency at elevated temperatures, thereby reducing or eliminating the need for post-treatment detoxification. Aspen wood (Populus tremula) was pretreated by NED 3.0 at 200 °C, followed by enzymatic hydrolysis and fermentation. The analytical results confirmed substantial reductions in common fermentation inhibitors, such as acetic acid (up to 2.18 g/100 g dry biomass) and furfural (0.18 g/100 g dry biomass), during early filtrate recovery. Hydrolysate analysis revealed a glucose yield of 26.41 g/100 g dry biomass, corresponding to a hydrolysis efficiency of 41.3%. Fermentation yielded up to 8.05 g ethanol/100 g dry biomass and achieved a fermentation efficiency of 59.8%. Inhibitor concentrations in both hydrolysate and fermentation broth remained within tolerable limits, allowing for effective glucose release and sustained fermentation performance. Compared with earlier NED configurations, the optimized system improved sugar recovery and ethanol production. These findings confirm the operational advantages of NED 3.0, including reduced inhibitory stress, simplified process integration, and chemical-free operation, underscoring its potential for scalability in line with the EU Green Deal for bioethanol production from woody biomass. Full article

Electrohydrodynamic atomization (EHDA) has significant advantages for microencapsulating compounds in various structures using biopolymers, where more research using pure starch is required. Concerning this, jicama starch and its hydrolysates have not yet been tested, despite their unique characteristics, which come from an alternative low-value-added crop source. Rapid acid hydrolysis of jicama starch with H₂SO₄ resulted in dextrins with a degree of hydrolysis (DE) from 0.4 to 19% within 1–12 h, and syrup solids at 24 h (DE = 42%). This process modifies the water retention capacity of jicama starch, gel viscosity, surface tension, and electrical conductivity. Hydrolyzed starch particles obtained by electrospraying (10 kV, L = 10 cm, Q = 2 mL/h) showed Feret diameters and roundness significantly influenced (p ≤ 0.05) by the degree of hydrolysis rather than the concentration of solids. It was found that hydrolyzed jicama starch with a DE < 6.3% can be used as the sole wall material to form particles by electrospraying, as they facilitate the formation of stable and rounded like-microspheres particles; this was not feasible above this threshold. The results suggest that the jicama starch’s ability to be used as a wall material in the electrospray synthesis of particles or microspheres appears to be determined by the degree of hydrolysis. Full article

The escalating demand for sustainable and eco-friendly production processes has necessitated the exploration of renewable resources for the synthesis of valuable chemicals. This study investigated the fermentative synthesis of gluconic acid (GA) and xylonic acid (XA) from hydrolyzed palm fronds by using Gluconobacter oxydans. The key variables examined included agitation speed, inoculum ratio, and composition of fermentation media. In a synthetic medium, maximum GA concentration reached 52.82 ± 12.88 g/L at 65 h using 150 rpm agitation and 15% (v/v) inoculation, while maximum XA concentration achieved 2.31 ± 1.43 g/L at 96 h using 220 rpm agitation and 9% (v/v) inoculation. In the hydrolysate medium, the maximum GA concentration was 3.24 ± 0.66 g/L at fermentation onset using 220 rpm agitation and 15% (v/v) inoculation, while the maximum XA concentration reached 0.62 ± 0.04 g/L at 24 h using 190 rpm agitation and 5% (v/v) inoculation. These findings demonstrate the feasibility of utilizing palm fronds as a renewable feedstock for the sustainable synthesis of high-value biochemicals, promoting waste valorization, and contributing to the advancement of a circular bioeconomy. Full article

This article presents a review of several non-exclusive pathways for the sequestration of soil organic carbon, which can be classified into two large classical groups: the modification of plant and microbial macromolecules and the abiotic and microbial neoformation of humic substances. Classical studies have established a causal relationship between aromatic structures and the stability of soil humus (traditional hypotheses regarding lignin and aromatic microbial metabolites as primary precursors for soil organic matter). However, further evidence has emerged that underscores the significance of humification mechanisms based solely on aliphatics. The precursors may be carbohydrates, which may be transformed by the effects of fire or catalytic dehydration reactions in soil. Furthermore, humic-type structures may be formed through the condensation of unsaturated fatty acids or the alteration of aliphatic biomacromolecules, such as cutins, suberins, and non-hydrolysable plant polyesters. In addition to the intrinsic value of understanding the potential for carbon sequestration in diverse soil types, biogeochemical models of the carbon cycle necessitate the assessment of the total quantity, nature, provenance, and resilience of the sequestered organic matter. This emphasises the necessity of applying specific techniques to gain insights into their molecular structures. The application of appropriate analytical techniques to soil organic matter, including sequential chemolysis or thermal degradation combined with isotopic analysis and high-resolution mass spectrometry, derivative spectroscopy (visible and infrared), or ¹³C magnetic resonance after selective degradation, enables the simultaneous assessment of the concurrent biophysicochemical stabilisation mechanisms of C in soils. Full article

Various pretreatment methods for the valorization of sunflower husks (SHs) for H₂ gas generation through fermentation by Escherichia coli were investigated. We analyzed thermal treatment (TT), acid hydrolysis (AH), and alkaline hydrolysis (AlkH) at different substrate concentrations (50 g L⁻¹, 75 g L⁻¹, 100 g L⁻¹, and 150 g L⁻¹) and dilution levels (undiluted, 2× diluted, and 5× diluted). A concentration of 75 g L⁻¹ SH that was acid-hydrolyzed and dissolved twice in the medium yielded optimal microbial growth, reaching 0.3 ± 0.1 g cell dry weight (CDW) L⁻¹ biomass. The highest substrate level enabling effective fermentation was 100 g L⁻¹, producing 0.37 ± 0.13 (g CDW) × L⁻¹ biomass after complete fermentation, while 150 g L⁻¹ exhibited pronounced inhibitory effects. It is worth mentioning that the sole alkaline treatment was not optimal for growth and H₂ production. Co-fermentation with glycerol significantly enhanced both biomass formation (up to 0.42 ± 0.15 (g CDW) × L⁻¹)) and H₂ production. The highest H₂ yield was observed during batch growth at 50 g L⁻¹ SH hydrolysate with 5× dilution, reaching up to 5.7 mmol H₂ (g sugar)⁻¹ with glycerol supplementation. This study introduces a dual-waste valorization strategy that combines agricultural and biodiesel industry residues to enhance clean energy generation. The novelty lies in optimizing pretreatment and co-substrate fermentation conditions to maximize both biohydrogen yield and microbial biomass using E. coli, a widely studied and scalable host. Full article

Arugula leaves (Diplotaxis tenuifolia L. and Eruca sativa L.) are a must-have ingredient in ready-to-eat salads, as they are prized for their appearance, taste, and flavor. The nutraceutical properties of this leafy vegetable are attributed to the presence of valuable secondary metabolites, such as phenolic acids and glucosinolates. Using UHPLC-Q-Orbitrap HRMS analysis and ion chromatography, we characterized the content of phenolic acids, glucosinolates, nitrates, and organic acids in organic arugula [Diplotaxis tenuifolia (L.) DC] and evaluated how the foliar application of three different non-microbial biostimulants (a seaweed extract, a vegetable protein hydrolysate, and a tropical plant extract) modulated the expression of these. Although the application of vegetable protein hydrolysate increased, compared to control plants, the nitrate content, the application of the same biostimulant increased the total content of glucosinolates and phenolic acid derivatives by 5.2 and 17.2%. Specifically, the foliar application of the plant-based biostimulant hydrolyzed protein significantly increased the content of glucoerucin (+22.9%), glucocheirolin (+76.8%), and ferulic acid (+94.1%). The highest values of flavonoid derivatives (173.03 μg g⁻¹ dw) were recorded from plants subjected to the exogenous application of seaweed extract. The results obtained underscore how biostimulants, depending on their origin and composition, can be exploited not only to improve agronomic performance but also to enhance the nutraceutical content of vegetables, guaranteeing end consumers a product with premium quality characteristics. Full article

Environmental challenges such as drought, high temperatures, and salinity compromise grapevine physiology, reduce productivity, and negatively affect grape and wine quality. In recent years, foliar applications of biostimulants, antitranspirants, and phytohormones have emerged as promising strategies to enhance stress tolerance in grapevines. This review focuses on the main effects of salinity, drought, and high temperatures and the combined impact of drought and high temperatures on grapevines and examines how foliar applications influence grapevine responses under these specific stress conditions. Synthesizing the recent findings from the last ten years (160 articles), it provides direct insights into the potential of these compounds to alleviate each type of stress, highlighting their effects on grapevine physiology, yield components, and secondary metabolites in berries. While their mechanism of action is not entirely clear and their efficacy can vary depending on the type of compound used and the grapevine variety, most studies report a beneficial effect or no effect on grapevines under abiotic stresses (either single or combined). Future research is necessary to optimize the concentrations of these compounds and determine the appropriate number and timing of applications, particularly under open-field experiments. Additionally, studies should assess the effect of foliar applications under multiple abiotic stress conditions. In conclusion, integrating foliar applications into vineyard management represents a sustainable technique to mitigate abiotic stresses associated with climate change, such as salinity, water deficit, and heat stress, while preserving or enhancing the quality of grapes and wines. Full article

Lactic acid bacteria (LAB) preserve many foods and play a vital role in fermented food products. This study designed a controlled biotechnological process of catfish (Clarias gariepinus) fermentation with a LAB starter culture isolated from corn hydrolysate. The BY (Barbu-Yelouassi) LAB strain was characterized regarding fermentative and antimicrobial potential, and its adaptability in the simulated gastrointestinal system (SGIS). After 10–12 h of cultivation on MRS broth (De Man Rogosa and Sharpe), the strain achieved the maximum exponential growth, produced maximum lactic acid (33.04%), and decreased the acidity up to pH 4. Also, the isolated strain showed increased tolerance to an acidic pH (3.5–2.0), high concentrations of salt (2–10%), and high concentrations of bile salts (≤2%). The behavior in SGIS demonstrated good viability after 2 h in artificial gastric juice (AGJ) (1 × 10⁷ CFU/mL) and up to 2 × 10³ CFU/mL after another 6 h in artificial intestinal juice (AIJ). The characterized BY strain was identified with the API 50CHL microtest (BioMerieux) as Lactiplantibacillus pentosus (Lbp. pentosus) (90.9% probability), taxon confirmed by genomic DNA sequencing. It was also demonstrated that Lbp. pentosus BY inhibited the growth of pathogenic bacteria, including Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and sporulated bacteria, such as Bacillus cereus. Additionally, it suppressed the sporulation of fungi like Aspergillus niger, Fusarium sp., and Penicillium sp. Furthermore, the Lbp. pentosus BY strain was used to ferment catfish, resulting in three variants of lanhouin (unsalted, with 10% salt, and with 15% salt), which exhibited good microbiological safety. Full article

A fluorescent sandwich assay was devised to quantify CK-MB. In a typical immunoassay, antibodies bind to the target, and the detected signal is quantified according to the target’s concentration. We innovated a unique fluorescence assay known as the “enzyme-linked aptamer assay” (ELAA) by substituting antibodies with a pair of high-affinity aptamers labelled with biotin, namely apt. A1 and apt. A2. Avidin-labelled ALP binds to biotin-labelled aptamers, hydrolyzing its substrate, 2-phosphoascorbic acid trisodium salt, resulting in the formation of ascorbic acid. The catalytic hydrolysate functions as a reducing agent, causing the deterioration of MoS₂ nanosheets. This results in the transformation of MoS₂ nanosheets into nanoribbons, leading to the release of quenched AGQDs. The reestablishment of fluorescence is triggered by Förster Resonance Energy Transfer (FRET) between the MoS₂ nanoribbons and AGQDs, enhancing the sensitivity of disease biomarker detection. The working range for detection falls between 2.5 nM and 160 nM, and the limit of detection (LOD) for CK-MB is verified at 0.20 nM. Full article

Muscle aging and atrophy in the elderly are closely associated with increased oxidative stress in muscle tissue. Bioactive peptides derived from protein hydrolysates have emerged as promising functional ingredients for alleviating sarcopenia due to their antioxidant properties and enrichment in essential amino acids. In a preliminary screening, mackerel protein hydrolysate (MPH) showed notable protective effects in a myotube atrophy model. This study evaluated the anti-atrophic potential of MPHs produced using different enzymes in H₂O₂-treated C2C12 myotubes. Among five hydrolysates, the alcalase-derived hydrolysate (MHA) demonstrated the most potent effects in maintaining myotube diameter, restoring myosin heavy chain (MYH) expression, and downregulating the atrophy-related genes MAFbx and MuRF1. Mechanistically, MHA activated the Akt/FoxO signaling pathway and inhibited NF-κB activation, thereby reducing muscle protein degradation. Additionally, MHA significantly lowered intracellular ROS levels and showed strong direct antioxidant activity. Amino acid and molecular weight profiling revealed high levels of essential amino acids and low-molecular-weight peptides, suggesting a synergistic contribution to its bioactivity. These findings suggest that MHA is a promising food-derived functional material with anti-atrophic and antioxidant properties and may be useful in preventing or managing age-related muscle loss such as sarcopenia, warranting further preclinical validation. Full article

Earthworms are valued as a dietary protein source in many regions. Earthworm protein can yield bioactive peptides, but enzymatic hydrolysis is inefficient by commercial proteases, and bioactivity development is still inadequate. This study developed a novel efficient method for degrading earthworm protein and investigated the lipid-lowering activity and mechanism of earthworm peptides. It was found that combining autolysis and alcalase exhibited a higher hydrolysis degree of earthworm protein of 43.64 ± 0.78% compared to using autolysis or alcalase only. The hydrolysate significantly reduced lipid accumulation in steatotic hepatocytes. LC-MS/MS results showed that the primary lipid-lowering peptides (EWPs) in the hydrolysate were small molecule peptides with molecular weights of 500–1000 Da and chain lengths of 4–7 amino acid residues. Western blot results demonstrated that EWP regulated the expression of lipid metabolism-related proteins, including APOC3, HMGCR, PCSK9, SREBP1, C/EBP-α, NPC1L1, PPAR-γ, and CYP7A1. Transcriptomic analysis and validation experiments indicated that the lipid-lowering activity of EWP was associated with its suppression of inflammatory factors, such as IL-6. This study presents an efficient enzymatic hydrolysis strategy for earthworm protein utilization, laying the foundation for its application in functional foods such as protein supplements, nutraceutical capsules, hypoallergenic infant formulas, and sports nutrition products. Full article

The presence of various inhibitory compounds in lignocellulosic hydrolysates poses a significant challenge for bioethanol production, requiring yeasts with exceptional multistress tolerance. This study introduces the novel application and demonstrates the robust performance of the nonconventional yeast Saccharomycodes ludwigii APRE2 for efficient bioethanol production directly from undetoxified sugarcane bagasse hydrolysate (SBH) at 37 °C. This approach critically eliminates the need for the costly detoxification pretreatments often required in industrial processes. Initial experiments confirmed S. ludwigii APRE2’s capability to ferment undetoxified SBH. To optimize fermentation efficiency, a central composite design (CCD) approach was implemented. This statistical method identified the following precise optimal parameters: sugar concentration (143.95 g/L), diammonium phosphate (4.99 g/L), pH (4.98), yeast extract (8.94 g/L), and magnesium sulfate (2.22 g/L). Under these optimized conditions, impressive results were achieved: a maximum ethanol concentration of 38.11 g/L, productivity of 1.59 g/L·h, and yield of 0.45 g/g. Notably, the ethanol productivity and theoretical yield achieved by S. ludwigii APRE2 using this inhibitor-rich, undetoxified SBH (containing acetic acid, formic acid, furfural, and 5-(hydroxymethyl)furfural) were superior to those previously reported for other ethanologenic yeasts under similar challenging conditions. This research establishes S. ludwigii APRE2 as a highly promising and industrially viable candidate for sustainable bioethanol production from lignocellulosic biomass, with its key novelty being its superior performance on undetoxified feedstocks, potentially reducing overall production costs. Full article

The growing demand for nutraceuticals has driven interest in upcycling low-value proteins from processed animal by-products and insect larvae into functional protein hydrolysates. This study evaluated five such hydrolysates in comparison to a high-value commercial reference (CPSP90), assessing the proximate composition, amino acid profile, molecular weight distribution, antioxidant activity, and bacterial growth dynamics. Results revealed a wide variability in the composition and bioactivity, driven by the raw material and processing conditions. All hydrolysates displayed a medium to high crude protein content (55.1–89.5% DM), with SHARK being the most protein-rich. SHARK and SWINE hydrolysates were particularly rich in collagenic amino acids, while FISH and CPSP90 contained higher levels of essential amino acids. FISH and INSECT demonstrated the strongest antioxidant activity, with INSECT also showing the highest protein solubility. INSECT and SWINE further displayed mild, selective antibacterial effects, indicating a potential for disease mitigation. Conversely, SHARK and FISH supported opportunistic bacteria growth, suggesting a potential use as nitrogen sources in microbial media. These findings highlight the nutritional and functional versatility of animal-derived protein hydrolysates and support their integration into sustainable feed strategies within a circular bioeconomy. Full article

Lactic acid bacteria are well known for hydrolyzing milk proteins, but their application to plant proteins remains limited. This study evaluated the ability of the cell-wall-anchored PrtS protease from two Streptococcus thermophilus strains to hydrolyze rapeseed albumins (RAs), aiming to generate bioactive peptides with potential food functionality. The specific activity of PrtS was first determined using a chromogenic substrate. RAs were then hydrolyzed using 10X- and 100X-concentrated cell pellets of each strain to assess the hydrolysis kinetics and the enzymatic mechanism. The results showed concentration-dependent hydrolysis, with protein conversion and the degree of hydrolysis increasing threefold at 100X for both strains. Despite the increased hydrolysis, the peptides produced had similar average sizes, averaging at five amino acids, indicating a consistent “one-by-one” cleavage mechanism. The in vitro testing of the RA hydrolysates produced with 100X PrtS from S. thermophilus LMD-9 revealed dose-dependent antioxidant activity comparable to native RAs. Importantly, unlike native RAs, these hydrolysates did not induce increased secretion of the pro-inflammatory mediator IL-8 in inflamed HT-29 cells, suggesting a reduced pro-inflammatory potential. These findings demonstrate that PrtS protease from S. thermophilus can effectively hydrolyze rapeseed proteins to produce functional hydrolysates with improved bioactivity profiles. Such hydrolysates have promising applications as functional ingredients in plant-based food products, contributing both to health benefits and potential food preservation through antioxidant activity. Full article