Search Results (192)

Bioprocessing grape pomace (GP) presents a sustainable solution aligned with circular economic principles and transforms it into valuable functional ingredients for baked products. This review (2020–2025) synthesizes enzymatic and microbial strategies that modify the fiber–phenolic matrix and improve dough performance. Enzyme-assisted extraction, alone or combined with ultrasound or pressurized liquids, increases extractable polyphenols and antioxidant capacity in GP fractions used as flour substitutions or pre-ferments. Fungal solid-state and lactic fermentations liberate bound phenolic compounds and generate acids and exopolysaccharides. Among these routes, enzyme-assisted extraction and lactic sourdough-type fermentations currently appear the most compatible with bakery-scale implementation, offering substantial phenolic enrichment while relying on relatively simple, food-grade equipment. In current bakery applications, GP is mainly used as crude grape pomace powder, which typically shows higher total phenolics and antioxidant capacity. Moreover, in several models it lowers starch hydrolysis and predicted glycemic index. The practical substitution rate is between 5 and 10% of flour, which balances nutritional gains with processing disadvantages. These can be mitigated by fractionation toward soluble dietary fiber or co-fortification with flours rich in protein and fiber. An additional benefit of these methods includes reduced mycotoxin bioaccessibility in vitro. A key evidence gap is the absence of standardized comparisons between raw and bioprocessed GP in identical formulations. Overall, GP emerges as a promising ingredient for bakery products, while the added technological and nutritional value of bioprocessing remains to be quantified. Full article

Leuconostoc mesenteroides is a key microorganism in food biotechnology, valued for its production of flavor-forming metabolites and exopolysaccharides, and its inclusion in starter cultures and biocatalytic systems. However, the application of advanced genetic tools to L. mesenteroides remains hindered by multiple barriers, including inefficient DNA transfer, elevated endogenous nuclease activity, and restriction–modification systems sensitive to plasmid methylation patterns. As a result, even widely accepted electroporation methodologies often yield inconsistent or irreproducible transformation results, limiting the strain’s amenability to metabolic engineering and synthetic biology applications. In this study, a reproducible electroporation protocol for the L. mesenteroides strain H32-02 Ksu is developed and experimentally validated. The protocol concept relies on the sequential optimization of key process steps: targeted weakening of the cell wall followed by osmotic protection, the development of a gentle electrical stimulus that ensures membrane permeability without critical damage, and the creation of recovery conditions that minimize loss of viability and degradation of incoming DNA. Matching plasmid methylation to the recipient’s restriction profile proved critical: choosing a source for plasmid DNA production with a compatible methylation pattern dramatically increased the likelihood of successful transformation. In our case, the selection of an E. coli strain with a more suitable methylation profile increased the yield of transformants by 3.5 times. It was also shown that reducing the pulse voltage increase transformant number by 3 times. The combined optimization resulted in an approximately 40-fold increase in transformation efficiency compared to the baseline level and, for the first time, provided consistently reproducible access to transformants of this strain. The highest transformation efficiency was achieved: 8 × 10² CFU µg⁻¹ DNA. The presented approach highlights the strain-specificity of barriers in Leuconostoc and forms a technological basis for constructing strains with desired properties, expressing heterologous enzymes, and subsequently scaling up bioprocesses in food and related industries. The methodological principles embodied in the protocol are potentially transferable to other lactic acid bacteria with similar limitations. Full article

Environmental and economic concerns due to the increasing use of fossil-based chemicals, especially fuel, may be alleviated by production of renewable fuels based on plant biomass, in particular, waste. Multistep cascades of enzymatic reactions are being increasingly sought to enhance the effectiveness of sustainable, environment-friendly processes. The biochemical transformation of lignocellulosic biomass and oils into fatty acid esters (“biodiesel”) involves biomass pretreatment, followed by polysaccharide hydrolysis and sugar fermentation to alcohol, either sequentially or simultaneously. Subsequent trans-esterification with waste or non-food-based oils is usually carried out in an organic solvent. Biocatalysis in aqueous emulsion offers significant advantages. This study presents a novel “one-pot” emulsion-based process for transforming unmodified cellulose and castor oil into biodiesel via hybridized yeasts with cellulose-coated micro-particles incorporating cellulolytic enzymes and lipases. The resultant consolidated bioprocess of saccharification, fermentation, and transesterification (cSFT) promotes effective substrate channeling and can potentially serve as a model for emulsion-based “one-pot” transformations of cellulose into valuable chemicals. Full article

This study investigated the anti-obesogenic effects of 3D-printed snacks—developed from indigenous composite inks of cowpea, sorghum, and orange-fleshed sweet potato—in male and female Wistar rats fed a high-fat diet (HFD). Four experimental diets (TD1–TD4) were formulated from snacks using two blend ratios (33.33%:33.33%:33.33%) and 50%:10%:40%) and two processing states (raw and bioprocessed). Following a five-week HFD-induction period, the rats were supplemented for an additional five weeks with diets containing 20% of these snacks, Orlistat, or HFD alone. Physiological assessments included body weight, fasting glucose, insulin, homeostatic model assessment for insulin resistance (HOMA-IR), serum lipids, sex hormones, angiotensin-converting enzyme (ACE) activity, and histological evaluation of cardiac tissue. HFD feeding induced hyperglycemia, dyslipidemia, and insulin resistance. Supplementation with the 3D-printed snacks improved glycemic control, with the TD4 (bioprocessed blend; 50:10:40%) restoring glucose levels close to baseline. TD1 and TD2 (raw blends) improved lipid and hormonal profiles in females, whereas TD3 (bioprocessed blend; 33.33%:33.33%:33.33%) significantly reduced triglycerides and elevated HDL in males. Importantly, only TD1 (raw blend; 33.33%:33.33%:33.33%) significantly reduced ACE activity in males, providing a unique cardioprotective mechanism not observed with other snack formulations. Histological analyses revealed inflammatory infiltration and fibroplasia in HFD and Orlistat groups, whereas all 3D-printed snacks preserved normal myocardial architecture without necrosis or fibrosis. Collectively, these findings demonstrate that 3D-printed snacks derived from indigenous composite inks improved metabolic dysfunctions associated with diet-induced obesity. The optimal formulation appears application-specific: TD4 for glycemic control, TD3 for lipid management in males, and TD1/TD2 for metabolic improvements in females. Full article

In this study, silver-decorated magnetite nanoparticles (Ag@Fe₃O₄) were synthesized via a green method using Brachychiton populneus leaf extract and employed as an efficient support matrix for immobilization of horseradish peroxidase (HRP). The biosynthesized nanocomposite exhibited magnetic properties that facilitated easy separation and reuse, while the silver loading imparted enhanced stability and potential antimicrobial activity. Comprehensive physicochemical characterizations, including XRD, FTIR, FESEM, EDX, BET, and VSM, confirmed the successful formation of Ag@Fe₃O₄ and effective enzyme loading. The immobilization yield of HRP on Ag@Fe₃O₄ reached 93%, and the immobilized enzyme showed improved tolerance toward temperature and pH variations, with an optimal pH of 7.5 and optimal temperature of 60 °C, compared to 7.0 and 50 °C for the free enzyme. Kinetic studies revealed a moderate increase in Km but maintained or slightly increased Vmax, indicating preserved catalytic efficiency. The immobilized enzyme demonstrated excellent reusability over 15 cycles (66% residual activity) and long-term storage stability (81% activity after 60 days at 4 °C). These enhancements are attributed to the protective microenvironment provided by the Ag@Fe₃O₄ matrix, which mitigates denaturation and leaching. This work highlights the potential of Ag@Fe₃O₄ as a sustainable and reusable platform for enzyme immobilization in biocatalytic applications, particularly in environmental remediation and industrial bioprocessing. Full article

The extensive use of antibiotics in animal husbandry leads to the release of unmetabolised residues and the dissemination of antimicrobial resistance genes (ARGs) in manure, posing environmental and public health challenges. Conventional treatment technologies, including hydrolysis, photodegradation, and phytoremediation, are often constrained by incomplete mineralisation, high cost, and environmental variability. Biocatalytic and microbially mediated processes are increasingly recognised as sustainable alternatives. Enzymes, which in clinical contexts confer resistance, can, in environmental matrices, catalyse the dismantling of antibiotic scaffolds, attenuating bioactivity and promoting detoxification. Catalytic classes such as hydrolases, transferases, and oxidoreductases mediate diverse transformations, including hydrolytic cleavage, functional group transfer, and oxidative modification. Microbial consortia and bioaugmentation further enhance biodegradation, while biochar and other amendments reduce ARG persistence. Advances in multi-omics, enzyme engineering, and immobilisation have expanded catalytic repertoires, improved stability, and enabled integration with composting, anaerobic digestion, and hybrid bioprocesses. Nonetheless, incomplete degradation, recalcitrant intermediates, and horizontal gene transfer remain challenges. Importantly, since degradation products may leach into soils and aquatic systems, optimising these processes is critical to prevent residues from entering the water cycle. This review synthesises advances in microbial and enzymatic degradation strategies, highlighting opportunities for sustainable manure management while mitigating water pollution risks. Full article

Phosphorus is a key macronutrient central to the processes of energy and information storage and exchange in the cell. Single-celled photosynthetic organisms, including microalgae, accumulate intracellular reserves of phosphorus (mostly in the form of polyphosphate) essential for the maintenance of cell homeostasis during fluctuations of external phosphorus availability. The polyphosphate reserves in microalgal cells are formed by polyphosphate polymerases—a ubiquitous enzyme family represented mainly by prokaryotic (PPK-type, typical of prokaryotes, e.g., cyanobacteria) and VTC-type polyphosphate polymerases harbored by eukaryotic microalgae, although certain species possess both PPK and VTC types of the enzyme. This enzyme is important for the environmental fitness of microalgae dwelling in diverse habitats, as well as for the efficiency of microalgae-based systems for the biocapture of phosphate from waste streams and for upcycling this valuable nutrient to agricultural ecosystems via biofertilizer from microalgal biomass. This review summarizes the recent progress in the field of structure, regulation, and functioning of VTC in microalgae. In conclusion, biotechnological implications and perspectives of VTC as a target of microalgal cell engineering and bioprocess design for improved phosphate bioremoval efficiency and culture robustness are considered. Full article

This study addressed the challenges posed by wet-grade maize distiller’s dried grains with solubles (DDGS), which are characterized by high moisture and complex fibers that limit their storage and utilization in poultry feed. Three experiments were conducted to enhance their nutritional value through enzymatic and solid-state fermentation treatments. In vitro pre-digestion using multiple enzymes significantly improved dry matter solubility (DMS) and reducing sugar yield for maize DDGS and the ingredient maize germ meal (MGM). Using optimized parameters, wet-based DDGS-MGM was subjected to solid-state fermentation with 500 mg/kg of cellulase and 200 mg/kg of the X1 enzyme (a laboratory-developed multi-enzyme complex), and this treatment enhanced both DMS and reducing sugar yield, and the resulting fermented product was subsequently applied in further experiments. In the broiler trial, forty 22-day-old Arbor Acres broilers with similar body weights were randomly assigned to five treatment groups, including the control group, (50% DDGS + 50% MGM) unfermented group, (62.5% DDGS + 37.5% MGM) unfermented group, (50% DDGS + 50% MGM) fermented group, and (62.5% DDGS + 37.5% MGM) fermented group, with eight replicates per treatment (one broiler per replicate). Replacement of 30% of the basal diet with fermented 50:50 DDGS-MGM material significantly increased apparent metabolizable energy (AME) and nitrogen-corrected AME by 2.74 MJ/kg and 2.73 MJ/kg, respectively, corresponding to improvements of 39.60% and 40.81% compared to the unfermented control (p < 0.05). Economic analysis indicated that using 5% fermented DDGS-MGM in feed reduced cost by 20.45 RMB per metric ton. These findings demonstrate that bioprocessing can improve the utilization and economic value of maize processing by-products, although further validation under practical conditions is needed. Full article

Water hyacinth is an invasive weed that can valorize through the production of hydrolytic enzymes via solid-state culture. This study explores the application of Trichoderma harzianum in producing xylanases and endoglucanases on water hyacinth beds. Laboratory-scale packed-bed column bioreactors (PBCBs) with a capacity of 8 grams of dry mass (g_dm) were used to evaluate the effects of temperature (28–36 °C) and initial moisture content (65–80%) on microbial growth and enzyme production. High yields of biomass and enzymes were produced at 30 °C. Moreover, xylanase activity was enhanced in cultures with a moisture content of 65% (~71.24 U/g_dm), and endoglucanase activity at 75–80% moisture (~20.13 U/g_dm). The operational conditions identified for xylanase production were applied to 6 L bench-scale cross-flow internally stirred bioreactors, packed to 40% capacity with 450 g_dm. Two stirring regimes were tested: intermittent and continuous. The results showed that continuous stirring promotes both microbial growth and xylanase activity. In fact, xylanase activity in continuous stirring conditions was comparable to that achieved in PBCBs. Consequently, continuous stirring enables a 56-fold increase in bioreactor capacity without compromising xylanase production. The approaches developed in this study can support the design of large-scale bioprocesses for the valorization of water hyacinth. Full article

The efficient degradation of lignin from agricultural by-products is a critical step in the development of sustainable bioprocessing technologies for waste valorisation. Enzymatic degradation of kraft lignin performed with lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (Lac) was investigated. A response surface methodology (RSM) based on a Box–Behnken Design (BBD) was employed in order to optimise key process parameters including enzyme concentration, lignin concentration, pH, incubation temperature, and activator concentration. The surface plots were used to determine the best conditions for each enzyme in order to better degrade kraft lignin. Therefore, LiP needed a stronger acidic environment and moderate temperature, MnP needed an almost neutral pH and moderate temperature, and Lac needed a neutral pH and higher temperature. This work contributes to the development of smart agricultural waste management practices by combining enzymatic treatments with statistical modelling for process optimisation. This study provides a framework for lignin degradation that can be used as a starting point for diverse lignocellulosic by-product fragmentation, thus supporting a circular bioeconomy initiative in accordance with today’s trends. The optimised enzymatic parameters could help enhance efficiency, enable process standardisation across feedstocks, and support economically and environmentally sustainable industrial-scale lignin valorisation in integrated biorefineries. Full article

Pectins are high-value plant cell-wall polysaccharides with extensive applications in the food, pharmaceutical, textile, paper, and environmental sectors. Traditional extraction and processing methodologies rely heavily on harsh acids, high temperatures, and non-renewable solvents, generating substantial environmental and economic costs. This review consolidates recent advances across the entire Bacillus–pectinase value chain, from green pectin extraction and upstream substrate characterization, through process and statistical optimization of enzyme production, to industrial biocatalysis applications. We propose a practical roadmap for developing high-efficiency, low-environmental-footprint enzyme systems that support circular bioeconomy objectives. Critical evaluation of optimization strategies, including submerged versus solid-state fermentation, response surface methodology, artificial neural networks, and design of experiments, is supported by comparative data on strain performance, fermentation parameters, and industrial titers. Sector-specific case studies demonstrate the efficacy of Bacillus pectinases in fruit-juice clarification, textile bio-scouring, paper bio-bleaching, bio-based detergents, coffee and tea processing, oil extraction, animal feed enhancement, wastewater treatment, and plant-virus purification. Remaining challenges, including enzyme stability in complex matrices, techno-economic scale-up, and structure-guided protein engineering, are identified. Future directions are charted toward CRISPR-driven enzyme design and fully integrated circular-economy bioprocessing platforms. Full article

Native yeasts are a promising microbial resource for the development of sustainable biorefineries. In this study, we isolated 30 yeast strains from soil, decaying wood, and tree bark in a preserved Araucaria Forest in Southern Brazil and characterized them phenotypically and taxonomically. All strains were able to grow on glucose, xylose, and cellobiose, and 50% of them could metabolize arabinose. Several isolates showed high growth rates on xylose (up to 0.47 h⁻¹) and cellobiose (up to 0.45 h⁻¹). Notably, 19 strains (63% of the analyzed yeasts) exhibited xylanase activity at 50 °C (up to 156.84 U/mL), and four strains (13%) showed significant cellulase production. β-Glucosidase activities were particularly high in permeabilized cells of CHAP-258, CHAP-277, and CHAP-278 (up to 584.33 U/mg DCW), with kinetic parameters indicating high enzymatic performance. Twelve strains (40% of the total) were classified as oleaginous, and three (10%) displayed both lipogenic and esterase activity. Lipase activity against p-nitrophenyl palmitate (pNPP) reached 55.55 U/mL in CHAP-260. Taxonomic identification revealed representatives of seven genera, including Meyerozyma, Papiliotrema, Scheffersomyces, and Sugiyamaella, with potential for biotechnological use. Overall, the biochemical diversity observed highlights the value of native yeasts from Araucaria Forests as biocatalysts for lignocellulose-based bioprocesses, particularly due to their ability to grow on pentoses, secrete hydrolytic enzymes, and accumulate lipids. Full article

Chitosanases are glycoside hydrolases (GHs) that catalyze the endo- or exo-type cleavage of β-1,4-glycosidic linkages in chitosan, enabling the selective production of chitooligosaccharides (COSs) with well-defined structures and diverse bioactivities. Owing to their substrate specificity and environmentally friendly catalytic action, chitosanases have garnered increasing attention as sustainable biocatalysts for COS production, with broad application potential in agriculture, food, medicine, and cosmetics. This review provides a comprehensive overview of recent advances in chitosanase research, focusing on the catalytic mechanisms and structure–function relationships that govern substrate selectivity and functional divergence across different GH families. Microbial diversity and heterologous expression systems for chitosanase production are discussed in parallel with biochemical characterization to support the rational selection of enzymes for specific biotechnological applications. Advances in protein engineering and computational approaches are highlighted as strategies to improve catalytic efficiency, substrate range, and stability. In addition, bioprocess optimization is addressed, with emphasis on fermentation using low-cost substrates and the application of immobilized enzymes and nano-biocatalyst systems for green and efficient COS production. Summarizing and discussing previous findings are essential to support future research and facilitate the development of next-generation chitosanases for sustainable industrial use. 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

Bio-based surfactants have demonstrated significant potential as economically viable and environmentally sustainable alternatives to petroleum-derived surfactants, with the global biosurfactant market expanding from USD 4.41 billion in 2023 to a projected USD 6.71 billion by 2032, representing a compound annual growth rate of 5.4%. While conventional surfactants such as alkyl aryl sulfates and alkyl benzene sulfonates exhibit extremely high aquatic toxicity and impose substantial ecological costs, biosurfactants including lipopeptides (surfactin, iturin, fengycin, lichenysin) produced by Bacillus species and glycolipids (rhamnolipids, sophorolipids, trehalose lipids, mannosylerythritol lipids) from Pseudomonas demonstrate superior biodegradability. However, current biosurfactant production costs, ranging from 5 to20 USD/kg, cannot compete effectively with synthetic surfactants, averaging approximately 2 USD/kg, necessitating comprehensive process improvements to achieve commercial viability. The utilization of renewable agricultural feedstocks containing 65–70% carbohydrates, including corn stover, sugarcane bagasse, rice bran, and palm oil mill effluent, has achieved production costs as low as 3.8 USD/kg through advanced optimized pretreatment technologies, enzyme catalysis, simultaneous saccharification and fermentation (SSF), and downstream processes, resulting in cost reductions compared to conventional methods. The implementation of artificial intelligence and machine learning algorithms for bioprocess optimization enables simultaneous optimization of genetic engineering, metabolic pathways, and fermentation parameters, achieving yield improvements and cost reductions, with projections indicating production costs below 2.50 USD/kg being needed in the next decade to achieve cost parity with synthetic surfactants, maintaining economic viability. Full article