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149 result(s) for "Cellobiose - biosynthesis"
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Cellobiose lipids: applications, production, and downstream processing
Cellobiose lipids (CBLs) are glycolipid biosurfactants that are widely applicable across diverse industries.CBLs have remarkable gelling, surface-active, and antifungal properties, making them ideal compounds for developing novel biotechnologies (e.g., biomaterials, detergents, and emulsifiers) with commercial potential.Various production methodologies have been developed via an interplay between producing organisms, media, and production approaches, each with its unique advantages and limitations toward scalability.Significant exploration is still required regarding downstream processing of CBLs because an optimised and scalable downstream technique is needed to complete the biotechnological cycle of CBL production.Finally, the industrialisation of CBL production requires the implementation of techno-economic and life-cycle assessments, which are currently understudied. Cellobiose lipids (CBLs) are glycolipid biosurfactants that have garnered attention due to their potential applications in diverse industries. Here, we review the current state of CBL research, from production and purification, to the potential applications of CBLs. We elucidate CBL functionality and consider some commercial applications, as well as how operating conditions (e.g., media and organism, or production approaches) impact productivity. Methodologies based on enzymatic synthesis or postproduction chemical modification of CBL variants are also presented. Given the importance of purity in current CBL applications, we discuss CBL separation and purification techniques. Finally, we highlight the importance of techno-economic and life-cycle assessments for the industrialisation of CBLs, while suggesting potential future routes for investigation. Cellobiose lipids (CBLs) are glycolipid biosurfactants that have garnered attention due to their potential applications in diverse industries. Here, we review the current state of CBL research, from production and purification, to the potential applications of CBLs. We elucidate CBL functionality and consider some commercial applications, as well as how operating conditions (e.g., media and organism, or production approaches) impact productivity. Methodologies based on enzymatic synthesis or postproduction chemical modification of CBL variants are also presented. Given the importance of purity in current CBL applications, we discuss CBL separation and purification techniques. Finally, we highlight the importance of techno-economic and life-cycle assessments for the industrialisation of CBLs, while suggesting potential future routes for investigation.
Bioprocess development for microbial production and purification of cellobiose lipids by the smut fungus Ustilago maydis DSM 4500
Cellobiose lipids (CBLs) are a class of glycolipid biosurfactants produced by various fungal strains. These compounds have gained significant interest due to their surface-active and antifungal properties, which are comparable to traditional synthetic surfactants and antimicrobials. Despite their potential applicability in various cosmetic, pharmaceutical, and agricultural formulations, significantly less research has been focused on their production and purification in comparison to other glycolipid biosurfactants, such as mannosylerythritol lipids (MELs) and sophorolipids. Hence, this work proposes the development of a bioprocess that involves the microbial production and high-level chromatographic purification of CBLs from a submerged culture of Ustilago maydis DSM 4500. After a highly purified CBL product was obtained, the factors affecting the production of this glycolipid were investigated. It was demonstrated that U. maydis DSM 4500 produces a specific structural variant of CBLs at a concentration of 1.36 g/L on an optimized the growth medium. Also, it was established that when the C/N ratio was decreased, the CBL titer increased by 2.3-fold. Furthermore, supplementing the culture with ZnSO 4 at a concentration of 0.04 mg/L further increased CBL concentration to 4.95 g/L, representing the highest CBL titer achieved in a single-stage bioprocess to date. This study developed a methodology for utilizing U. maydis as a high-level CBL producer, which could challenge other familiar CBL producers, such as Sporisorium scitamineum and Cryptococcus humicola .
Expression and characterization of a glucose-tolerant β-1,4-glucosidase with wide substrate specificity from Cytophaga hutchinsonii
Cytophaga hutchinsonii is a gram-negative bacterium that can efficiently degrade crystalline cellulose by a novel strategy without cell-free cellulases or cellulosomes. Genomic analysis implied that C. hutchinsonii had endoglucanases and β-glucosidases but no exoglucanases which could processively digest cellulose and produce cellobiose. In this study, BglA was functionally expressed in Escherichia coli and found to be a β-glucosidase with wide substrate specificity. It can hydrolyze p NPG, p NPC, cellobiose, and cellodextrins. Moreover, unlike most β-glucosidases whose activity greatly decreases with increasing length of the substrate chains, BglA has similar activity on cellobiose and larger cellodextrins. The K m values of BglA on cellobiose, cellotriose, and cellotetraose were calculated to be 4.8 × 10 −2 , 5.6 × 10 −2 , and 5.3 × 10 −2  mol/l, respectively. These properties give BglA a great advantage to cooperate with endoglucanases in C. hutchinsonii in cellulose degradation. We proposed that C. hutchinsonii could utilize a simple cellulase system which consists of endoglucanases and β-glucosidases to completely digest amorphous cellulose into glucose. Moreover, BglA was also found to be highly tolerant to glucose as it retained 40 % activity when the concentration of glucose was 100 times higher than that of the substrate, showing potential application in the bioenergy industry.
The Differential Proteome of the Probiotic Lactobacillus acidophilus NCFM Grown on the Potential Prebiotic Cellobiose Shows Upregulation of Two β-Glycoside Hydrolases
Probiotics, prebiotics, and combinations thereof, that is, synbiotics, are known to exert beneficial health effects in humans; however interactions between pro- and prebiotics remain poorly understood at the molecular level. The present study describes changes in abundance of different proteins of the probiotic bacterium Lactobacillus acidophilus NCFM (NCFM) when grown on the potential prebiotic cellobiose as compared to glucose. Cytosolic cell extract proteomes after harvest at late exponential phase of NCFM grown on cellobiose or glucose were analyzed by two dimensional difference gel electrophoresis (2D-DIGE) in the acidic (pH 4–7) and the alkaline (pH 6–11) regions showing a total of 136 spots to change in abundance. Proteins were identified by MS or MS/MS from 81 of these spots representing 49 unique proteins and either increasing 1.5–13.9-fold or decreasing 1.5–7.8-fold in relative abundance. Many of these proteins were associated with energy metabolism, including the cellobiose related glycoside hydrolases phospho-β-glucosidase (LBA0881) and phospho-β-galactosidase II (LBA0726). The data provide insight into the utilization of the candidate prebiotic cellobiose by the probiotic bacterium NCFM. Several of the upregulated or downregulated identified proteins associated with utilization of cellobiose indicate the presence of carbon catabolite repression and regulation of enzymes involved in carbohydrate metabolism.
Nutritional regulation and kinetics of flocculosin synthesis by Pseudozyma flocculosa
This study sought to identify the factors and conditions that affected production of the antifungal glycolipid flocculosin by the biocontrol agent Pseudozyma flocculosa. For this purpose, different parameters known or reported to influence glycolipid release in fungi were tested. Concentration of the start-up inoculum was found to play an important role in flocculosin production, as the optimal level increased productivity by as much as tenfold. Carbon availability and nitrogen source (i.e., organic vs inorganic) both had a direct influence on the metabolism of P. flocculosa, leading to flocculosin synthesis. In general, if conditions were conducive for production of the glycolipid, carbon availability appeared to be the only limiting factor. On the other hand, if yeast extract was supplied as nitrogen source, fungal biomass was immediately stimulated to the detriment of flocculosin synthesis. Unlike other reports of glycolipid release by yeast-like fungi, inorganic nitrogen starvation did not trigger production of flocculosin. The relationship between the factors influencing flocculosin production in vitro and the conditions affecting the release of the molecule by P. flocculosa in its natural habitat appears to be linked to the availability of a suitable and plentiful food source for the biocontrol agent.
Multistage Process to Enhance Cellobiose Production from Cellulosic Materials
Cellobiose, a disaccharide, is a valuable product that can be obtained from cellulose hydrolysis. In this study, a simple methodology is presented to enhance the production and improve the selectivity of cellobiose during enzymatic hydrolysis of cellulose. The approach consisted of a multistage removal of filtrate via vacuum filtration and resuspension of the retentate. By this process, the remaining solid was further hydrolyzed without additional enzyme loading. Compared to the continuous hydrolysis process, the production of cellobiose increased by 45%. Increased selectivity of cellobiose is due to the loss of β-glucosidases in the filtrate, while enhanced productivity is likely due to mitigated product inhibition.
Use of Cellulase Inhibitors to Produce Cellobiose
The economics driving biorefinery development requires high value-added products such as cellobiose for financial feasibility. This research describes a simple technology for increasing cellobiose yields during lignocellulosic hydrolysis. The yield of cellobiose produced during cellulose hydrolysis was maximized by modification of reaction conditions. The addition of an inhibitor from the group that includes glucose oxidase, gluconolactone, and gluconic acid during cellulase hydrolysis of cellulose increased the amount of cellobiose produced. The optimal conditions for cellobiose production were determined for four factors; reaction time, cellulase concentration, cellulose concentration, and inhibitor concentration using a Box-Behnken experimental design. Gluconolactone in the cellulase system resulted in the greatest production of cellobiose (31.2%) from cellulose. The yield of cellobiose was 23.7% with glucose oxidase, similar to 21.9% with gluconic acid.
Elucidating carbohydrate preference and engineering glucose transport in Caldimonas thermodepolymerans for enhanced polyhydroxyalkanoate production
Caldimonas thermodepolymerans DSM 15344, a moderately thermophilic bacterium, has emerged as a promising candidate for next-generation industrial biotechnology (NGIB) due to its ability to utilize lignocellulose-derived sugars for polyhydroxyalkanoate (PHA) production. This study assesses its metabolic potential by evaluating the utilization of various plant-derived sugars and their mixtures, with a focus on xylose, glucose, and cellobiose. The results indicate that C. thermodepolymerans exhibits a strong preference for xylose (3.97 g/L PHB) over glucose (2.28 g/L PHB) but demonstrates even greater efficiency in metabolizing cellobiose (4.96 g/L PHB). However, extracellular hydrolysis of cellobiose leads to glucose accumulation, which constrains overall productivity. Our findings suggest that the primary limitation in glucose metabolism is inefficient glucose transport rather than intracellular catabolism. To address this bottleneck, the glf glucose facilitator gene from the mesophilic bacterium Zymomonas mobilis was introduced into C. thermodepolymerans , enhancing its glucose utilization capacity. The engineered strain (Cald_GLF3) exhibited significantly improved PHA productivity, particularly when cultivated on sugar mixtures containing cellobiose. Despite being grown at suboptimal temperatures due to the thermal instability of Glf from Z. mobilis , Cald_GLF3 outperformed the wild-type strain, achieving notably high PHA yields when cultivated with cellobiose as the sole carbon source (9.26 g/L PHB). These findings highlight the critical role of glucose transport in the metabolism of C. thermodepolymerans and suggest that targeted engineering can further enhance its biotechnological potential. This study establishes C. thermodepolymerans as a promising thermophilic chassis for PHA production from lignocellulosic sugars, contributing to sustainable biopolymer synthesis. Key points C. thermodepolymerans DSM 15344 produces PHA from lignocellulose-derived sugars Xylose and cellobiose are preferred substrates, while glucose is poorly utilized Deficient glucose transport in DSM 15344 restored by Zymomonas mobilis glf gene
The application of bacteria-derived dehydrogenases and oxidases in the synthesis of gold nanoparticles
In this work the green synthesis of gold nanoparticles (Au-NPs) using the oxidoreductive enzymes Myriococcum thermophilum cellobiose dehydrogenase ( Mt CDH), Glomerella cingulata glucose dehydrogenase ( Gc GDH), and Aspergillus niger glucose oxidase ( An GOX)) as bioreductants was investigated. The influence of reaction conditions on the synthesis of Au-NPs was examined and optimised. The reaction kinetics and the influence of Au ions on the reaction rate were determined. Based on the kinetic study, the mechanism of Au-NP synthesis was proposed. The Au-NPs were characterized by UV–Vis spectroscopy and transmission electron microscopy (TEM). The surface plasmon resonance (SPR) absorption peaks of the Au-NPs synthesised with Mt CDH and Gc GDH were observed at 535 nm, indicating an average size of around 50 nm. According to the image analysis performed on a TEM micrograph, the Au-NPs synthesized with Gc GDH have a spherical shape with an average size of 2.83 and 6.63 nm after 24 and 48 h of the reaction, respectively. Key points • The Au NPs were synthesised by the action of enzymes CDH and GDH. • The synthesis of Au-NPs by CDH is related to the oxidation of cellobiose. • The synthesis of Au-NPs by GDH was not driven by the reaction kinetic. Graphical Abstract
Overexpression and characterization of a glucose-tolerant β-glucosidase from T. aotearoense with high specific activity for cellobiose
Thermoanaerobacterium aotearoense P8G3#4 produced β-glucosidase (BGL) intracellularly when grown in liquid culture on cellobiose. The gene bgl, encoding β-glucosidase, was cloned and sequenced. Analysis revealed that the bgl contained an open reading frame of 1314 bp encoding a protein of 446 amino acid residues, and the product belonged to the glycoside hydrolase family 1 with the canonical glycoside hydrolase family 1 (GH1) (β/α)₈ TIM barrel fold. Expression of pET-bgl together with a chaperone gene cloned in vector pGro7 in Escherichia coli dramatically enhanced the crude enzyme activity to a specific activity of 256.3 U/mg wet cells, which resulted in a 9.2-fold increase of that obtained from the expression without any chaperones. The purified BGL exhibited relatively high thermostability and pH stability with its highest activity at 60 °C and pH 6.0. In addition, the activities of BGL were remarkably stimulated by the addition of 5 mM Na⁺ or K⁺. The enzyme showed strong ability to hydrolyze cellobiose with a K ₘ and V ₘₐₓ of 25.45 mM and 740.5 U/mg, respectively. The BGL was activated by glucose at concentration varying from 50 to 250 mM and tolerant to glucose inhibition with a K ᵢ of 800 mM glucose. The supplement of the purified BGL to the sugarcane bagasse hydrolysis mixture containing a commercial cellulase resulted in about 20 % enhancement of the released reducing sugars. These properties of the purified BGL should have important practical implication in its potential applications for better industrial production of glucose or bioethanol started from lignocellulosic biomass.