Search Results (349)

Residual microalgal biomass generated during wastewater phytoremediation represents an underexploited resource for developing sustainable bioprocesses. This study investigated the biotechnological valorization of phytoremediation-derived Chlorella biomass through an integrated process combining α-amylase-assisted saccharification and fermentation with the non-conventional yeast Wickerhamomyces sp. UFFS-CE-3.1.2 in a stirred-tank bioreactor. Following physical pretreatment to enhance intracellular compound accessibility, fermentation was conducted for 72 h under anaerobic conditions, and temporal changes in enzymatic activities and fermentation-associated compounds were monitored by spectrophotometric assays and high-performance liquid chromatography (HPLC), respectively. The integrated process exhibited distinct temporal profiles of hydrolytic and antioxidant enzyme activities, with maximum activities of 1275.23 U/mL for catalase, 1014.59 U/mL for ascorbate peroxidase, 1291.67 U/mL for protease, and 228.75 U/mL for lipase. Amylase activity remained detectable throughout the 72 h process. Total sugars decreased from 8.88 g/L at 0 h to 0.03 g/L at 72 h. In comparison, glycerol peaked at 5.62 g/L at 18 h, and ethanol remained at approximately 1.0 g/L between 18 and 48 h. Because several enzymatic activities were already detected before yeast inoculation, the observed profiles cannot be attributed exclusively to Wickerhamomyces sp. and should instead be interpreted as characteristics of the integrated bioprocess. Overall, the results demonstrate that residual Chlorella biomass generated during wastewater phytoremediation can serve as a renewable feedstock for further biotechnological processing, supporting an extended valorization pathway within a circular bioprocessing framework. Full article

Food waste (FW) valorization through resource recovery is central to circular economy strategies that reduce environmental burden while generating sustainable, bio-based chemicals. This work investigated the effect of anaerobic sludge inoculum and the process control parameters of temperature (35 °C and 55 °C), pH value (4–10), and total solids content (2.5%, 5%, 7.5% and 10%) on the recovery of volatile fatty acids (VFAs)—chemicals used in bioplastics and bioenergy production—during acidogenic fermentation of food waste in batch reactors. While FW is well studied for biogas production, its potential for VFA recovery, a strategy that adds economic value to waste streams and supports the circular bioeconomy, remains comparatively underexplored. Mesophilic conditions favored fermentation over thermophilic conditions, and pH was the most influential factor affecting VFA accumulation, although temperature, inoculum presence, and total solids content also had statistically significant, large effects. Basic pH values provided maximum VFA yields from 2% to 25%, roughly double the acidic pH yields, while the highest solids content (10%) minimized VFA production at both temperatures. The highest yield (25%) occurred at T = 35 °C, pH 9, and TS = 5%, without sludge, while the highest yield under thermophilic conditions (T = 55 °C) reached 22.4% at TS = 2.5% and pH 9. By systematically evaluating these parameters together, this study offers a more comprehensive understanding of FW acidogenic fermentation than prior single-parameter works, guiding bioprocess design for sustainable waste management and resource efficiency. Full article

2,3-Butanediol (2,3-BD) is a versatile bulk chemical, serving as a high-boiling green solvent, a key monomer for polyesters and polyurethanes, and a crucial intermediate in the production of fine chemicals and cosmetics. Additionally, it is a key intermediate for pharmaceuticals and agrochemicals, supporting green chemistry. Microbial production of 2,3-BD offers a sustainable bioprocess but faces the challenge of high-concentration product inhibition. In an effort to improve 2,3-BD tolerance and production in Corynebacterium glutamicum, the engineered strain CGK4 was subjected to atmospheric and room temperature plasma (ARTP) mutagenesis, from which three superior mutant strains were isolated. Genomic and reverse engineering analyses revealed two mutations beneficial for tolerance and seven mutations beneficial for production. Among these, mutations atpG^L250P, cobT^V192V, and ctaE^L79P increased 2,3-BD titer by 18.0%, 14.5%, and 15.0%, respectively. Furthermore, we found that while certain mutations markedly enhanced stress tolerance, the highest-producing strains achieved a balanced metabolic state rather than maximal tolerance, indicating a non-linear relationship between the two traits. Finally, through mutation combination optimization, the optimal strain K4-cobT-ctaE was constructed. In shake-flask fed-batch fermentation, this strain produced 84.35 ± 3.04 g/L (2R,3R)-2,3-BD, which was 38.3% higher than that of the parental strain. Our findings provide a promising approach to addressing 2,3-BD tolerance challenges and promote the development of microbial production platforms for industrial application. Full article

This study integrates microbial biotechnology, bioprocess optimization, and circular bioeconomy principles to valorize oilseed agro-industrial coproducts as low-cost inducing substrates for lipase production. Palm kernel cake (PKC), canola cake, andiroba cake, and brewer’s spent grain were evaluated as carbon sources for extracellular lipase production by the wild-type strain Trichoderma sp. LEPM-711 under submerged fermentation. Qualitative screening in olive oil/rhodamine B medium confirmed the strain’s lipolytic potential. Among the substrates tested, PKC showed the strongest induction, reaching 4.68 U mL⁻¹, and was therefore selected for nitrogen supplementation and statistical optimization. Peptone supplementation increased lipolytic activity to 8.41 U mL⁻¹ after 72 h. A Plackett–Burman design identified CaCl₂·2H₂O, CoCl₂·6H₂O, and peptone as significant medium components, while response surface methodology established the optimal operational conditions as pH 6.0, 10⁶ spores mL⁻¹, and 2% (w/v) PKC. Under these conditions, the crude enzymatic extract reached 18.31 U mL⁻¹ at pH 7.0 and 45 °C, corresponding to an approximately 3.9-fold increase over the initial PKC fermentation. These findings support the use of Trichoderma sp. LEPM-711 and oilseed coproducts as a sustainable platform for enzyme production and residue upgrading within applied natural sciences. Full article

Tomato (Solanum lycopersicum L.) exhibits extensive cultivar diversity in fruit morphology, color, and bioactive compounds. These are closely associated with genetic background, ripening stage, and carotenoid metabolic regulation. Carotenoids, especially lycopene and β-carotene, are major determinants of tomato coloration and are also nutritionally and industrially important high-value-added antioxidants. Carotenoid profiles are regulated by changes in related biosynthetic pathways, including precursor supply, desaturation, isomerization, and cyclization. Key genes such as PSY1, CRTISO, LCY-B and LCY-E play central roles in carotenoid synthesis and accumulation, thereby determining color phenotypes. Mutations and genome-editing (CRISPR/Cas9) approaches can modify carotenoid metabolic flux and develop cultivars with improved nutritional traits. Furthermore, advanced and sustainable recovery strategies for carotenoids (ultrasound-, microwave-, enzyme-, high-pressure-, deep eutectic solvent-, and supercritical fluid-assisted extraction methods) have been developed for efficient pigment extraction. In this review, we compare the physiological and molecular characteristics of diverse cultivars and traits of advanced bioprocesses in terms of carotenoid extraction efficiency and solvent safety. Finally, we discuss various encapsulation techniques that improve product stability and storage performance in industrial applications. Taken together, we review practical strategies combining cultivar-based carotenoid production, sustainable recovery, and product stabilization. Full article

Metal–organic frameworks (MOFs) have emerged as a versatile class of porous nanomaterials with exceptional surface area, tunable pore architectures, and customizable chemical functionalities, creating new opportunities for advanced food applications. Increasing demand for functional foods, precision fermentation, and sustainable bioprocessing has stimulated interest in MOFs as multifunctional platforms for microbial encapsulation, biocatalyst stabilization, and resource recovery. This review examines recent advances in the design and application of MOFs for probiotic delivery, precision fermentation, and circular food systems. The relationships between MOF structure, physicochemical properties, and functional performance are discussed in the context of probiotic encapsulation, protection against environmental and gastrointestinal stress, and controlled release within the intestinal tract. Emerging applications in precision fermentation are evaluated, including microbial immobilization, enzyme stabilization, metabolite separation, and bioprocess intensification. The potential of MOFs to enable circular food systems through the valorization of fermentation by-products, nutrient recovery, and waste-to-value strategies is also assessed. Despite significant progress, challenges related to biocompatibility, food-grade synthesis, scalability, regulatory approval, and long-term safety continue to limit industrial implementation. Future research directions include the development of sustainable and biodegradable MOFs, data-driven material design, and standardized evaluation frameworks to accelerate the translation of MOF-enabled technologies from laboratory research to commercial food applications. Full article

Spent coffee grounds (SCGs) are waste products obtained after brewing roasted coffee beans. The detoxification-based process used in the preparation of defatted spent coffee grounds (SCGO) involves: (i) direct acid pretreatment followed by enzymatic-hydrolysis (AE), (ii) solvent extraction followed by acid pretreatment and enzyme-hydrolysis (SAE), and (iii) solvent extraction followed by acid pretreatment and enzymatic-hydrolysis coupled with activated carbon detoxification (SAEAc) for polyhydroxyalkanoates (PHA) production. SCGO was subjected to optimized acid pretreatment (100 °C, 2.0% H₂SO₄, 6 h), followed by enzyme saccharification (20 FPU/g of SCGO). The effect of detoxification on the obtained hydrolysates was comparatively evaluated based on their inhibitor concentrations and suitability as substrates for fermentation by Lysinibacillus sp. RG.S. and PHA biosynthesis. The maximum biomass productivity (5.6 ± 0.44 g/dm³), PHA accumulation (53.0 ± 1.22%), and PHA yield (2.97 ± 0.32 g/dm³) were produced by the hydrolysates that were generated by the SAEAc-detoxification process with 1% corn steep liquor (CSL) and 1% acetic acid. The physicochemical and thermo-stable properties of the produced PHA were found to be comparable to those of standard PHB, making it appealing for a variety of applications. Extracted bioactive compounds from SCGO were employed as reducing and stabilizing agents for the synthesis of silver nanoparticles (AgNPs). Analytical results suggest that the SCGO-AgNPs were well phyto-fabricated and evenly dispersed, with particle diameters of about 10–40 nm. Furthermore, SCGO-AgNPs demonstrated potential antioxidant and antidiabetic activities, indicating their prospective for biomedical and nutraceutical applications. The foregoing results illustrate that detoxification strategy enhances the fermentability of SCGO hydrolysate and extracted bioactive compounds are used for biofunctional synthesis of AgNPs. In summary, the integrated cascading biorefinery concept supports sustainable and economically viable valorization of SCGO. Full article

Agri-food byproducts are increasingly investigated as food-tech material resources, but compositional richness alone does not establish ingredient suitability. This critical narrative review evaluates plant-derived and processing residues across four representative material groups: fiber- and polysaccharide-rich powders and fractions, protein- and starch-rich materials, bioprocessed ingredients, and formulation-supporting composites. We examine how source identity, stabilization, drying, milling, fermentation, enzymatic modification, fractionation, and formulation influence hydration, interfacial behavior, gelation, rheology, texture, sensory compatibility, storage stability, and preservation-supporting performance. Evidence is interpreted across linked feedstock–processing–functionality–application–readiness gates, with separate consideration of safety, regulatory positioning, batch specifications, scale-up, techno-economic feasibility, life cycle assessment, and circularity boundaries. The practical output is a five-gate decision support and claim calibration framework that distinguishes four proposed evidence levels: Candidate, Functionality-supported, Formulation-validated, and Industry-ready potential. As a proposed non-numerical synthesis, the framework supports decision-making and claim calibration rather than ranking, certification, or regulatory approval; it identifies the evidence required before matrix-specific functional, safety, sustainability, or industry relevance claims are made. Full article

Poly[(R)-3-hydroxybutyrate] [P(3HB)] is a biological polyester synthesized by microorganisms and can be used as a biodegradable plastic. The higher the molecular weight of P(3HB), the stronger it can be processed into films and fibers. Therefore, high-molecular-weight P(3HB) can be used as high-performance plastics for engineering and specialty applications. The P(3HB) biosynthetic operon consists of three genes, canonically arranged as phaC-phaA-phaB (phaCAB). This study specifically rearranges the phaCAB operon to the phaBCA order to investigate P(3HB) production and its molecular weight from glucose and/or xylose, which can be derived from wood hydrolysates, using Escherichia coli XL1-Blue as a host. By rearranging the gene order to phaBCA, the expression balance of PHA synthase (PhaC, encoded by phaC) and 3HB monomer-supplying enzymes (PhaA and PhaB, encoded by phaA and phaB, respectively) changed, enabling the host to produce P(3HB) with a higher molecular weight than that with the canonical operon. This effect was significant when xylose was used as the carbon source or when a nutritionally rich medium was used. However, the amount of P(3HB) produced by the phaCAB-expressing strain was consistently better than that by the phaBCA-expressing strain. This study establishes that high-molecular-weight P(3HB) can be produced through an integrated approach of operon engineering and wood-derived sugar bioprocessing, offering a sustainable production route for high-performance biodegradable plastics from non-food biomass. Full article

Cocoa bean quality is strongly influenced by microbial fermentation, which drives flavour development through enzymatic activity. Despite its importance, the specific microorganisms, particularly those producing pectinase, remain poorly characterized. This study aimed to identify and evaluate pectinase-producing microbes from fermenting cocoa mass and assess their impact on fermentation performance. In the first experiment, 9 bacterial and 14 yeast strains were isolated and screened on pectinase screening agar. Three yeast strains (FF1D3, FF2D1, and NA) showed high pectinolytic activity. FF1D3 and FF2D1 were identified as Pichia kudriavzevii, whereas NA showed only a low-confidence closest BLAST match to Candida orthopsilosis and was therefore not advanced as a starter culture candidate. These strains had the highest polygalacturonase activity at 24–48 h and pectin lyase activity at 48–72 h. In the second experiment, inoculating cocoa beans with these strains significantly enhanced fermentation kinetics, with yeast populations reaching log10⁹, indicating enhanced fermentation via accelerated sugar utilization. Brix values (1.97–3.11) and pH reduction (p  <  0.01) confirmed active microbial metabolism and effective acidification. Phenolic content varied significantly (p  <  0.01), with FF2D1 and combined treatments showing elevated levels due to strain-dependent enzymatic hydrolysis. The combined starter culture showed potential to improve fermentation consistency and accelerate sugar utilization. These findings highlight the potential of targeted microbial inoculation to optimise cocoa fermentation and quality. Full article

This article presents the IST-Yeasts Culture Collection (IST-Yeasts CC), which is a newly established repository dedicated to non-conventional blue yeasts isolated from (micro)algae-associated environments in Portugal. This collection currently comprises 115 yeast strains, the majority of which belong to the phylum Basidiomycota (92%), the genus Rhodotorula (69%), including R. mucilaginosa, R. diobovata, R. sphaerocarpa, and R. taiwanensis species. Other Basidiomycota species in the collection are: Cystobasidium minutum, C. slooffiae, Vishniacozyma carnescens, Moesziomyces aphidis, Sporobolomyces roseus, S. salmonicolor, and Naganishia diffluens. The collection also includes species from the Ascomycota phylum, such as Meyerozyma guilliermondii, Yamadazyma atlantica, and Cyberlindnera vartiovaarae. An initial functional screening performed, with one representative isolate per species, revealed the ability of these strains to produce carotenoids, lipids, riboflavin, biosurfactants, bioemulsifiers and auxins, as well as their capacity to grow on a broad range of carbon sources. These traits underscore their biotechnological potential within the circular bioeconomy and sustainable bioprocesses, positioning them as promising sources of bioactive natural products. By providing access to a diverse panel of marine-associated yeasts, the IST-Yeasts CC supports the development of innovative solutions in marine biotechnology and marine drug discovery, including the design of more resilient and high-performance algal cultivation systems through targeted co-cultivation strategies. Further information on the collection can be found at IST-Yeasts CC website. Full article

The global transition toward plant-based diets has driven the inclusion and legumes as primary sources of proteins and micronutrients. However, the raw whole seed hosts complex matrices of antinutritional factors and crystalline starch arrangements that limit proteolytic digestibility, chelate essential minerals, and induce accelerated postprandial glycemic responses. Conventional culinary and thermal treatments applied in isolation are frequently insufficient to disrupt the physicochemical matrix of the seeds, leaving critical gaps regarding how to sustainably optimize mineral bioaccessibility and convert water-soluble starches into stable slowly digestible fractions. This scoping review synthesizes analytical evidence demonstrating that targeted fermentative bioprocessing acts as a microstructural modulator. However, these biochemical outcomes are not unidirectional; the expansion of nutritional value is strictly governed by a complex interplay of substrate properties, process moisture, pH adjustments, and thermal pretreatments in plant defense frameworks and spatially reorganizing starch polymers. Microbial organic acid production and the mechanical penetration of fungal hyphae promote a 90–100% degradation and elimination of phytates and condensed tannins, eliminating non-digestible galacto-oligosaccharides and inactivating trypsin inhibitors. These mechanisms optimize phytate-to-mineral molar ratios, doubling the bioaccessibility of iron, zinc, and calcium in the digestive aqueous phases, while microbial beta-glucosidase expression bioconverts conjugated glycosides into free aglycones with high antioxidant activity. Simultaneously, the induction of molecular retrogradation drives continuous increases in the resistant starch fraction, inducing significant reductions in the hydrolysis index and lowering the predictive glycemic index to low thresholds. These findings consolidate controlled fermentation as a viable biotechnological intervention, providing structural guidelines for the rational design of functional foods, biofortified baked goods, and vegan beverages with high digestive tolerance. Full article

The global proliferation of microplastics demands sustainable remediation alternatives to energy-intensive conventional disposal methods, shifting research focus toward polymer-degrading microbial communities within the “plastisphere.” The primary objectives of this study are twofold: first, to systematically decode the sequential biophysical mechanisms underlying microplastic colonization and enzymatic degradation; and second, to establish an empirically validated, scalable treatment framework that employs both a novel biological isolate and a hybrid engineering architecture. Experimentally, we investigate the multi-stage colonization process and demonstrate that “Phase Zero” conditioning films modulate the surface zeta potential (ζ) to anchor pioneer r-strategists. To evaluate degradative efficacy under accelerated conditions without abiotic pretreatment, the newly isolated carp gut strain Hafnia paralvei UUNT_MP29 was exposed to pristine low-density polyethylene (LDPE) and polystyrene (PS). Over a 16-day biotic incubation period, structural and chemical alterations were distinctly polymer-specific: bacterial action on the polyolefin LDPE yielded a Carbonyl Index of 0.4594 and a 10.95 °C reduction in thermal stability (T_max), whereas the aromatic PS matrix exhibited a Carbonyl Index of 0.3235 alongside a 10.80 °C decrease in T_max, with both substrates showing intense surface pitting. To standardize these complex tracking metrics across the field, a universal four-pillar Biodegradability Index (BI) was formulated. Based on these findings, we recommend an immediate transition from passive waste containment to a closed-loop engineering approach. Specifically, we propose integrating an artificial intelligence (AI)-managed hybrid bioprocess configuration that couples Advanced Oxidation Processes (AOPs) with Membrane Bioreactors (MBRs). This dual-stage configuration is recommended to overcome polyolefin crystallinity, accelerate stoichiometric mineralization, and actively mitigate additive-mediated toxicity at the industrial scale, providing a vital blueprint for the circular bio-economy. Full article

Multi-effect evaporators are widely used in biomanufacturing to create concentrates of fermentation-derived products prior to or during crystallization, where the discharge concentration directly governs crystal product quality. However, bioprocess feed streams are subject to large and irregular disturbances arising from batch-to-batch fermentation variability and cell separation operations, making stable concentration control essential. In this study, a dynamic differential-algebraic model of a three-effect evaporator was developed, in which product composition evolves according to mass balance ordinary differential equations, while vapor and concentrate flows are determined algebraically from energy balances. Using this model, the discharge concentration was controlled against a representative feed composition disturbance scenario by comparing proportional–integral–derivative (PID) control with model predictive control (MPC). The PID controller failed to suppress the disturbance and exhibited sustained oscillations due to the large structural time delay and composition-dependent nonlinearity of the cascaded process. In contrast, the terminal-cost MPC predicted future behavior from the process model and compensated for disturbances preemptively, maintaining the discharge concentration almost exactly at its set point. The integrated absolute error decreased from 0.3872 for PID to 0.00145 for MPC with a 99.6% improvement. These results demonstrate that MPC enables robust product quality control in disturbance-rich biomanufacturing processes. Full article

Developing advanced bioinspired photoprotective barrier from marine resources represents a critical frontier of bioprocessing. This study established a rational design and implementation of effective photoprotective surface-coating eumelanin from ink of an Indian squid (Uroteuthis duvaucelii). The Central Composite Design was developed to optimize extraction and functionalization parameters of eumelanin on quartz substrates, strategically developing the matrix for peak optical attenuation within the potential Far-UVC window (220 nm). Translational photoprotective efficacy of the surface, as well as finished eumelanin on quartz surface, was validated by subjecting them to a challenging macro-level biological assay using a hospital-grade 254 nm ultraviolet germicidal source (125 µWcm⁻²). Quantitative physical dosimetry established that the squid eumelanin coating (A254 = 1.00) reduced internal transmittance to approximately 10%, successfully dampening the incident fluence from 0.225 J cm⁻² down to a heavily attenuated 0.0225 J cm⁻² at the biological sample plane. While unshielded control indicator microbial strains suffered complete lethal inactivation, the eumelanin barrier maintained exceptional cell viability, yielding biological shielding efficiencies of 98% for Bacillus subtilis, 96% for Staphylococcus aureus, and 92% for Escherichia coli. Characteristic features from FE-SEM, FTIR, and XRD analysis established that this superior photoprotective property is governed by the extensively conjugated, π-π-stacked indolic architecture possessing a characteristic 3.4 Å interlayer d-spacing, which facilitates rapid, non-radiative energy dissipation. This work establishes an effective framework for translating squid biomass into high-value, transparent optical barriers, providing a potential sustainable alternative to synthetic ultraviolet absorbers. Full article