Bioethanol production from lignocellulosic materials is hindered by the high costs of pretreatment and the enzymes. The present study aimed to evaluate whether co-cultivation of four selected cellulolytic fungi yields higher cellulase and xylanase activities compared to the monocultures and to investigate whether the enzymes from the co-cultures yield higher saccharification on selected plant materials without thermo-chemical pretreatment. The fungal isolates, Trichoderma reesei F118, Penicillium javanicum FS7, Talaromyces sp. F113, and Talaromyces pinophilus FM9, were grown as monocultures and binary co-cultures under submerged conditions for 7 days. The cellulase and xylanase activities of the culture filtrates were measured, and the culture filtrates were employed for the saccharification of sugarcane leaves, Guinea grass leaves, and water hyacinth stems and leaves. Total reducing sugars and individual sugars released from each plant material were quantified. The co-culture of Talaromyces sp. F113 with Penicillium javanicum FS7 and of T. reesei F118 with T. pinophilus FM9 produced significantly higher cellulase activities compared to the corresponding monocultures whereas no effect was observed on xylanase activities. Overall, the highest amounts of total reducing sugars and individual sugars were obtained from Guinea grass leaves saccharified with the co-culture of T. reesei F118 with T. pinophilus FM9, yielding 63.5% saccharification. Guinea grass leaves were found to be the most susceptible to enzymatic saccharification without pre-treatment, while water hyacinth stems and leaves were the least. Accordingly, the study suggests that fungal co-cultivation could be a promising approach for the saccharification of lignocellulosic materials for bioethanol production.
- MeSH
- celulasa * metabolismus MeSH
- endo-1,4-beta-xylanasy metabolismus MeSH
- ethanol metabolismus MeSH
- Hypocreales enzymologie metabolismus růst a vývoj MeSH
- kokultivační techniky * MeSH
- lignin * metabolismus MeSH
- listy rostlin mikrobiologie MeSH
- Penicillium * enzymologie metabolismus růst a vývoj MeSH
- Saccharum * mikrobiologie metabolismus MeSH
- Talaromyces * enzymologie metabolismus růst a vývoj MeSH
- Publikační typ
- časopisecké články MeSH
The aim of this study was to determine the effects of xylanase and flaxseed the performance of chickens, digesta viscosity, nutrient retention, fatty acid profile in muscle, tibia strength and interrelations of these factors in broiler chickens fed a wheat-based diet. Seven hundred and twenty one-day-old Ross 308 cockerels were assigned to four treatments according to the contents of flaxseed (0 and 80 g/kg) and xylanase (0 and 0.1 g/kg) in the diet. Xylanase significantly decreased the intake of feed (p < 0.001), decreased feed conversion (p < 0.001), and reduced mortality (p = 0.050). In addition, xylanase significantly increased the retention of all nutrients (p = 0.010 -<0.001) except crude fibre, the fat content in breast meat (p = 0.029) and liver (p = 0.019) and the concentration of polyunsaturated fatty acids (PUFAs) in meat (p = 0.002). Flaxseed supplementation did not influence performance but decreased the retention of dry matter (p = 0.016), crude protein (p = 0.012), organic matter (p = 0.016) and nitrogen-free extract (p = 0.008). Xylanase in combination with flaxseed increased the content of n-3 fatty acids in the breast meat (p = 0.006). The lowest n-6/n-3 ratio (p = 0.001) was detected in the flaxseed and flaxseed combined with xylanase groups. Significant interaction effects of flaxseed and xylanase on tibia strength (p = 0.030) and tibia ash content (p = 0.009) were detected. The administration of xylanase or flaxseed alone increased tibia strength. Compared with the control diet, the addition of flaxseed to the diet increased the digesta viscosity (p = 0.043) in the ileum, whereas the addition of xylanase decreased the level of this indicator. It can be concluded that xylanase is an enzyme suitable for increasing nutrient availability, and in the case of its addition to a flaxseed diet, it can reduce the antinutritional effect of flaxseed by reducing the viscosity of the digesta and increasing the content of health-promoting n-3 PUFAs.
- MeSH
- endo-1,4-beta-xylanasy * metabolismus MeSH
- fyziologie výživy zvířat MeSH
- kostní denzita účinky léků MeSH
- krmivo pro zvířata * analýza MeSH
- kur domácí * MeSH
- len * chemie MeSH
- polysacharidy * farmakologie MeSH
- potravní doplňky * analýza MeSH
- tibie účinky léků MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The use of microbial enzymes is highly encouraged in paper and pulp industries to reduce the excessive use of hazardous chemicals. During the study, xylanase of Bacillus stratosphericus EB-11 was characterized for pulp bleaching applications. The extracellular xylanase was produced under submerged fermentation using bamboo waste as a natural carbon source. There was fast cell division and enzyme production under optimized fermentation conditions in the bioreactor. The highest activity was 91,200U after 30 h of growth with Km and Vmax of 3.52 mg/mL and 391.5 μmol/min per mg respectively. The purified enzyme with molecular mass ~ 60 kDa had conferred positive activity on native PAGE. The strong inhibition by ethylenediaminetetraacetate and SDS showed the metallo-xylanase nature of the purified enzyme. The bacterial xylanase reduces the use of hydrogen peroxide by 0.4%. Similarly, biological oxygen demand and chemical oxygen demand were reduced by 42.6 and 35.2%. The xylanase-hydrogen peroxide combined treatment and conventional chlorine dioxide-alkaline (CDE1D1D2) bleaching showed almost similar improvement in physicochemical properties of bamboo pulp. Xylanase-peroxide bleaching reduces the lignin content to 4.95% from 13.32% unbleached pulp. This content after CDE1D1D2 treatment was 4.21%. The kappa number decreased from 15.2 to 9.46 with increasing the burst factor (15.51), crystallinity index (60.25%), viscosity (20.1 cp), and brightness (65.4%). The overall finding will encourage the development of new cleaner methods of bleaching in the paper and pulp industry.
- MeSH
- Bacillus * MeSH
- endo-1,4-beta-xylanasy MeSH
- lignin chemie MeSH
- peroxid vodíku MeSH
- sloni * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The influence of light regulation on the growth and enzyme production of three endolichenic fungal isolates, i.e. Pseudopestalotiopsis theae (EF13), Fusarium solani (EF5), and Xylaria venustula (PH22), was determined. The isolates were exposed to blue, red, green, yellow, white fluorescent light (12 h light-12 h dark photoperiod) (test), and 24 h dark (control) conditions. Results revealed that the alternating light-dark conditions resulted in the formation of dark rings in most fungal isolates but was absent in PH22. Red light induced sporulation while yellow light elicited higher biomass in all isolates (0.19 ± 0.01 g, 0.07 ± 0.00 g, and 0.11 ± 0.00 g, for EF13, PH22, and EF5, respectively) as compared to incubation in the dark. Results also showed that blue light induced higher amylase activity in PH22 (15.31 ± 0.45 U/mL) and L-asparaginase activity in all isolates (0.45 ± 0.01 U/mL, 0.55 ± 0.39 U/mL, and 0.38 ± 0.01 U/mL, for EF13, PH22, and EF5, respectively) compared to both control conditions. Green light enhanced the production of xylanase (6.57 ± 0.42 U/mL, 10.64 ± 0.12 U/mL, and 7.55 ± 0.56 U/mL for EF13, PH22, and EF5, respectively) and cellulase (6.49 ± 0.48 U/mL, 9.57 ± 0.25 U/mL, and 7.28 ± 0.63 U/mL, for EF13, PH22, and EF5, respectively). In contrast, red light was the least effective light treatment as production of enzymes was the least, with lower levels of amylase, cellulase, xylanase, and L-asparaginase detected. To conclude, all three endolichenic fungi are light-responsive, with fungal growth regulated with the use of red light and yellow light, and manipulation of enzyme production via blue and green light.
- MeSH
- amylasy MeSH
- asparaginasa * MeSH
- celulasy * MeSH
- endo-1,4-beta-xylanasy MeSH
- Publikační typ
- časopisecké články MeSH
To better understand the production of enzymes of industrial interest from microorganisms with biotechnological potential using lignocellulosic biomass, we evaluated the production of endoglucanase and xylanase from Aspergillus tamarii. CAZymes domains were evaluated in the genome, and a screening of the enzymatic potential of A. tamarii in various agricultural biomasses was done. The enzymatic profile could be associated with the biomass complexity, with increased biomass recalcitrance yielding higher activity. A time-course profile defined 48 h of cultivation as the best period for cultivating A. tamarii in sugarcane bagasse reached 12.05 IU/mg for endoglucanase and 74.86 IU/mg for xylanase. Using 0.1% (w/v) tryptone as the only nitrogen source and 12 μmol/L CuSO4 addition had an overall positive effect on the enzymatic activity and protein production. A 22 factorial central composite design was used then to investigate the simultaneous influence of tryptone and CuSO4 on enzyme activity. Tryptone strongly affected enzymatic activity, decreasing endoglucanase activity but increasing xylanase activity. CuSO4 supplementation was advantageous for endoglucanases, increasing their activity, and it had a negative effect on xylanases. But overall, the experimental design increased the enzymatic activity of all biomasses used. For the clean cotton residue, the experimental design was able to reach the highest enzyme activity for endoglucanase and xylanase, with 1.195 IU/mL and 6.353 IU/mL, respectively. More experimental studies are required to investigate how the biomass induction effect impacts enzyme production.
Endo-glucanase (cellulase) and xylanase have high industrial demand due to their vast application in industrial processes. This study reports statistical based experimental optimization for co-production of endo-glucanase and xylanase from Bacillus sonorensis BD92. Response surface methodology (RSM) involving central composite design (CCD) with full factorial experiments (23) was applied to elucidate the components that significantly affect co-production of endo-glucanase and xylanase. The optimum co-production conditions for endo-glucanase and xylanase were as follows: carboxymethyl cellulose (CMC) 20 g/L, yeast extract 15 g/L, and time 72 h. The maximum endo-glucanase and xylanase production obtained was 1.46 and 5.69 U/mL, respectively, while the minimum endo-glucanase and xylanase production obtained was 0.66 and 0.25 U/mL, respectively. This statistical model was efficient because only 20 experimental runs were necessary to assess the highest production conditions, and the model accuracy was very satisfactory as coefficient of determination (R2) was 0.95 and 0.89 for endo-glucanase and xylanase, respectively. Further, potential application of these enzymes for saccharification of lignocellulosic biomass (wheat bran, wheat straw, rice straw, and cotton stalk) was also investigated. The results revealed that the biomass was susceptible to enzymatic saccharification and the amount of reducing sugars (glucose and xylose) increased with increase in incubation time. In conclusion, Bacillus sonorensis BD92 reveals a promise as a source of potential endo-glucanase and xylanase producer that could be useful for degrading plant biomass into value-added products of economic importance using precise statistically optimized conditions.
- MeSH
- Bacillus růst a vývoj metabolismus MeSH
- biomasa * MeSH
- celulasa biosyntéza MeSH
- endo-1,4-beta-xylanasy biosyntéza MeSH
- fermentace MeSH
- hydrolýza MeSH
- průmyslová mikrobiologie metody MeSH
- rýže (rod) metabolismus MeSH
- sodná sůl karboxymethylcelulosy MeSH
- statistické modely MeSH
- Publikační typ
- časopisecké články MeSH
Genes encoding glycosyl hydrolase family 11 (GH11) xylanases and xylanases have been identified from Pseudobutyrivibrio xylanivorans. In contrast, little is known about the diversity and distribution of the GH10 xylanase in strains of P. xylanivorans. Xylanase and associated activities of P. xylanivorans have been characterized in detail in the type strain, Mz5. The aim of the present study was to identify GH10 xylanase genes in strains 2 and Mz5 of P. xylanivorans. In addition, we evaluated degradation and utilization of xylan by P. xylanivorans 2 isolated from rumen of Creole goats. After a 12-h culture, P. xylanivorans 2 was able to utilize up to 53% of the total pentose content present in birchwood xylan (BWX) and to utilize up to 62% of a ethanol-acetic acid-soluble fraction prepared from BWX. This is the first report describing the presence of GH10 xylanase-encoding genes in P. xylanivorans. Strain 2 and Mz5 contained xylanases which were related to GH10 xylanase of Butyrivibrio sp. Identifying xylanase-encoding genes and activity of these enzymes are a step toward understanding possible functional role of P. xylanivorans in the rumen ecosystem and contribute to providing an improved choice of enzymes for improving fiber digestion in ruminant animals, agricultural biomass utilization for biofuel production, and other industries.
- MeSH
- bachor mikrobiologie MeSH
- Bacteria klasifikace enzymologie genetika izolace a purifikace MeSH
- bakteriální proteiny chemie genetika metabolismus MeSH
- endo-1,4-beta-xylanasy chemie genetika metabolismus MeSH
- fylogeneze MeSH
- kinetika MeSH
- kozy MeSH
- xylany metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
A glycosyl hydrolase family 10 endoxylanase from Bacillus sp. HJ14 was grouped in a separated cluster with another six Bacillus endoxylanases which have not been characterized. These Bacillus endoxylanases showed less than 52% amino acid sequence identity with other endoxylanases and far distance with endoxylanases from most microorganisms. Signal peptide was not detected in the endoxylanase. The endoxylanase was expressed in Escherichia coli BL21 (DE3), and the purified recombinant enzyme (rXynAHJ14) was characterized. rXynAHJ14 was apparent optimal at 62.5 °C and pH 6.5 and retained more than 55% of the maximum activity when assayed at 40-75 °C, 23% at 20 °C, 16% at 85 °C, and even 8% at 0 °C. Half-lives of the enzyme were more than 60 min, approximately 25 and 4 min at 70, 75, and 80 °C, respectively. The enzyme exhibited more than 62% xylanase activity and stability at the concentration of 3-30% (w/v) NaCl. No xylanase activity was lost after incubation of the purified rXynAHJ14 with trypsin and proteinase K at 37 °C for 60 min. Different components of oligosaccharides were detected in the time-course hydrolysis of beechwood xylan by the enzyme. During the simulated intestinal digestion phase in vitro, 11.5-19.0, 15.3-19.0, 21.9-27.7, and 28.2-31.2 μmol/mL reducing sugar were released by the purified rXynAHJ14 from soybean meal, wheat bran, beechwood xylan, and rapeseed meal, respectively. The endoxylanase might be an alternative for potential applications in the processing of sea food and saline food and in aquaculture as agastric fish feed additive.
- MeSH
- Bacillus enzymologie genetika MeSH
- chlorid sodný metabolismus MeSH
- endo-1,4-beta-xylanasy chemie genetika izolace a purifikace metabolismus MeSH
- endopeptidasa K metabolismus MeSH
- Escherichia coli genetika MeSH
- exprese genu MeSH
- klonování DNA MeSH
- koncentrace vodíkových iontů MeSH
- molekulární sekvence - údaje MeSH
- proteolýza MeSH
- rekombinantní proteiny chemie genetika izolace a purifikace metabolismus MeSH
- sekvenční analýza DNA MeSH
- sekvenční homologie aminokyselin MeSH
- stabilita enzymů MeSH
- teplota MeSH
- trypsin metabolismus MeSH
- xylany metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Xylanase III (Xyn III), a specific endoxylanase that belongs to family 10 of the glycoside hydrolases, was overexpressed in Trichoderma reesei QM9414 using a constitutive strong promoter of the gene encoding pyruvate decarboxylase (pdc). The maximum recombinant xylanase activity achieved was 817.2 ± 65.2 U/mL in the transformant fermentation liquid. The productivities of Xyn III accounted for approximately 53% of the total protein secreted by the recombinant. The enzyme was optimally active at 60 °C and pH 6. The recombinant Xyn III was stable at pH 5-8. This is the first report on the homologous expression of xyn3 in T. reesei QM9414. The properties of Xyn III make it promising in a variety of industrial use.
Enzymes from cold-adapted species are significantly more active at low temperatures, even those close to zero Celsius, but the rationale of this adaptation is complex and relatively poorly understood. It is commonly stated that there is a relationship between the flexibility of an enzyme and its catalytic activity at low temperature. This paper gives the results of a study using molecular dynamics simulations performed for five pairs of enzymes, each pair comprising a cold-active enzyme plus its mesophilic or thermophilic counterpart. The enzyme pairs included alpha-amylase, citrate synthase, malate dehydrogenase, alkaline protease and xylanase. Numerous sites with elevated flexibility were observed in all enzymes; however, differences in flexibilities were not striking. Nevertheless, amino acid residues common in both enzymes of a pair (not present in insertions of a structure alignment) are generally more flexible in the cold-active enzymes. The further application of principle component analysis to the protein dynamics revealed that there are differences in the rate and/or extent of opening and closing of the active sites. The results indicate that protein dynamics play an important role in catalytic processes where structural rearrangements, such as those required for active site access by substrate, are involved. They also support the notion that cold adaptation may have evolved by selective changes in regions of enzyme structure rather than in global change to the whole protein.
- MeSH
- amylasy chemie MeSH
- bakteriální proteiny chemie MeSH
- citrátsynthasa chemie MeSH
- endo-1,4-beta-xylanasy chemie MeSH
- endopeptidasy chemie MeSH
- enzymy chemie metabolismus MeSH
- financování organizované MeSH
- malátdehydrogenasa chemie MeSH
- molekulární modely MeSH
- nízká teplota MeSH
- počítačová simulace MeSH
- sekundární struktura proteinů MeSH
- Publikační typ
- srovnávací studie MeSH
