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1.
Braz J Microbiol ; 55(2): 1151-1166, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38472698

ABSTRACT

Developing efficient microbiological methods to convert polysaccharide-rich materials into fermentable sugars, particularly monosaccharides, is vital for advancing the bioeconomy and producing renewable chemicals and energy sources. This study focused on optimizing the production conditions of an enzyme cocktail from Aspergillus niger ATCC 9642 using solid-state fermentation (SSF) and assessing its effectiveness in saccharifying mango peels through a simple, rapid, and efficient one-step process. A rotatable central composite design was employed to determine optimal conditions of moisture, time, and pH for enzyme production in SSF medium. The optimized enzyme cocktail exhibited cellulase activity (CMCase) at 6.28 U/g, filter paper activity (FPase) at 3.29 U/g, and pectinase activity at 117.02 U/g. These optimal activities were achieved with an SSF duration of 81 h, pH of 4.66, and a moisture content of 59%. The optimized enzyme cocktail effectively saccharified the mango peels without the need for chemical agents. The maximum saccharification yield reached approximately 81%, indicating efficient conversion of mango peels into sugars. The enzyme cocktail displayed consistent thermal stability within the tested temperature range of 30-60°C. Notably, the highest sugar release occurred within 36 h, with glucose, arabinose, galactose, and xylose being the primary monosaccharides released during saccharification. This study highlights the potential application of Aspergillus niger ATCC 9642 and SSF for enzymatic production, offering a simple and high-performance process for monosaccharide production. The optimized enzyme cocktail obtained through solid-state fermentation demonstrated efficient saccharification of mango peels, suggesting its suitability for industrial-scale applications.


Subject(s)
Aspergillus niger , Fermentation , Mangifera , Aspergillus niger/enzymology , Aspergillus niger/metabolism , Mangifera/microbiology , Mangifera/chemistry , Hydrogen-Ion Concentration , Cellulase/metabolism , Cellulase/chemistry , Temperature , Polygalacturonase/metabolism , Enzyme Stability , Hydrolysis , Fungal Proteins/metabolism
2.
Bioresour Technol ; 364: 128019, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36162784

ABSTRACT

Despite decades of research and industrial applications of Trichoderma reesei, the development of industrially relevant strains for enzyme production including a low-cost and scalable bioprocess remains elusive. Herein, bioprocess optimization, pilot plant scale-up, techno-economic analysis and life-cycle assessment for enzyme production by an engineered T. reesei strain are reported. The developed bioprocess increased in âˆ¼ 2-fold protein productivity (0.39 g.L-1.h-1) and 1.6-fold FPase activity (196 FPU.L-1.h-1), reducing the fermentation in 4 days. Cultivation in a 65-L pilot plant bioreactor resulted in 54 g.L-1 protein in 7 days, highlighting the robustness and scalability of this bioprocess. Techno-economic analysis indicates an enzyme cost of âˆ¼ 3.2 USD.kg-1, which is below to the target proposed (4.24 USD.kg-1) in the NREL/TP-5100-47764 report, while life-cycle assessment shows a carbon footprint reduction of approximately 50% compared to a typical commercial enzyme. This study provides the fundamental knowledge for the design of economically competitive Trichoderma technologies for industrial use.


Subject(s)
Cellulase , Trichoderma , Animals , Trichoderma/metabolism , Cellulase/metabolism , Bioreactors , Fermentation , Life Cycle Stages
3.
Appl Biochem Biotechnol ; 194(2): 848-861, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34553326

ABSTRACT

Pectinases are widely used in a variety of industrial processes. However, their application is limited by low catalytic processivity, reduced stability, high cost, and poor re-use compatibility. These drawbacks may be overcome by enzyme immobilization with ferromagnetic nanoparticles, which are easily recovered by a magnetic field. In this work, an endopolygalacturonase from Chondrostereum purpureum (EndoPGCp) expressed in Pichia pastoris was immobilized on glutaraldehyde-activated chitosan ferromagnetic nanoparticles (EndoPGCp-MNP) and used to supplement a commercial enzyme cocktail. No significant differences in biochemical and kinetic properties were observed between EndoPGCp-MNP and EndoPGCp, although the EndoPGCp-MNP showed slightly increased thermostability. Cocktail supplementation with EndoPGCp-MNP increased reducing sugar release from orange wastes by 1.8-fold and showed a synergistic effect as compared to the free enzyme. Furthermore, EndoPGCp-MNP retained 65% of the initial activity after 7 cycles of re-use. These properties suggest that EndoPGCp-MNP may find applications in the processing of pectin-rich agroindustrial residues.


Subject(s)
Polygalacturonase
4.
World J Microbiol Biotechnol ; 35(8): 114, 2019 Jul 22.
Article in English | MEDLINE | ID: mdl-31332537

ABSTRACT

N-acetyl-D-glucosamine (GlcNAc) is an important amino-monosaccharide with great potential for biotechnological applications. It has traditionally been produced by the chemical hydrolysis of chitin, despite certain industrial and environmental drawbacks, including acidic wastes, low yields and high costs. Therefore, enzymatic production has gained attention as a promising environmentally-friendly alternative to the chemical processes. In this study we demonstrate the GlcNAc bioproduction from colloidal α-chitin using an enzyme cocktail containing endochitinases and exochitinases (chitobiosidases and N-acetyl-glucosaminidases). The enzyme cocktail was extracted after fermentation in a bioreactor by Aeromonas caviae CHZ306, a chitinolytic marine bacterium with great potential for chitinase production. Hydrolysis parameters were studied in terms of temperature, pH, enzyme and substrate concentration, and reaction time, achieving over 90% GlcNAc yield within 6 h. The use of colloidal α-chitin as substrate showed a substantial improvement of GlcNAc yields, when compared with ß-chitin and α-chitin polymorphs. Such result is directly related to a significant decrease in crystallinity and viscosity from natural α-chitin, providing the chitinase with greater accessibility to the depolymerized chains. This study provides valuable information on the GlcNAc bioproduction from chitin using an enzymatic approach, addressing the key points for its production, including the enzyme cocktail composition and the substrate structures.


Subject(s)
Acetylglucosamine/biosynthesis , Aeromonas caviae/enzymology , Chitin/metabolism , Chitinases/metabolism , Culture Media/chemistry , Hydrogen-Ion Concentration , Hydrolysis , Magnetic Resonance Spectroscopy , Molecular Weight , Temperature , Viscosity , X-Ray Diffraction
5.
Rev. colomb. biotecnol ; 14(1): 171-181, ene.-jun. 2012. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-656949

ABSTRACT

En esta investigación, se hidrolizó un sustrato deslignificado proveniente de residuos de la cosecha caña de azúcar (hojas y cogollos) usando un preparado enzimático con 27.53 unidades de papel filtro (FPU), obtenido a partir de enzimas comerciales. La hidrólisis se llevó a cabo a un pH de 4.2 y una temperatura de 50 oC. Fueron analizados modelos de inhibición por sustrato, glucosa e inhibición total por producto. Los resultados mostraron que los modelos que mejor se ajustan a los datos experimentales, son los modelos de inhibición competitiva por glucosa, con una constante de Michaelis (Km) de 20.37 g/L, velocidad máxima (Vmax) 39 g/L h y una constante de inhibición (ki) de 0.442. En el caso que las relaciones enzima – Sustrato (E/S) sean mayores de 0.5, se puede aplicar el modelo cinático de Michaelis-Menten.


In this research, a delignified substrate from crops residues sugar cane residues (leaves and top cane) was hydrolyzed using an enzyme preparation with 27.53 FPU. This enzyme was obtained from trade. Hydrolysis was carried out to pH of 4.2 and a temperature of 50 oC. Models of inhibition models substrate, glucose and total inhibition product was analyzed. The results showed that models that best fit the data experimental was the models competitive glucose inhibition (Km= 20.37, Vmax=39 and ki= 0.442). In the event that E/S is above 0.5, can applied kinetic models of Michaelis – Menten.


Subject(s)
Enzymes , Waste Products , Commercial Wastes , Crops, Agricultural , Models, Animal
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