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1.
Carbohydr Polym ; 320: 121176, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659785

RESUMO

A co-metabolization of xylose and glucose by Schizophyllum commune 227E.32 wild mushroom for exopolysaccharide (EPS) production is presented. Cultivations performed with S. commune 227E.32 at different xylose concentrations demonstrated that the concentration of 50 g·L-1 of xylose achieved the highest EPS production, around 4.46 g·L-1. Scale-up in a stirred tank reactor (STR) was performed. 10 % inoculum showed the highest cost/benefit ratio regarding sugar conversion and EPS production (Y P/S = 0.90 g·g-1), achieving 1.82 g·L-1 of EPS. Isolation, purification, and characterization were conducted with EPS produced in flasks and STR. GC-MS analysis showed glucose as main monosaccharide constituents for both isolates. 13C NMR and HSQC-edited showed that both EPS isolated consisted of a ß-D-Glcp (1 â†’ 3) main chain, partially substituted at O-6 with nonreducing ß-D-Glcp ends on every third residue, similar to ß-D-glucan isolated from S. commune basidiomes known as schizophyllan (SPG). The Mw was determined by GPC to 1.5 × 106 Da (flasks) and 1.1 × 106 Da (STR). AFM topographs revealed a semi-flexible appearance of the ß-D-glucan, consistent with the triple helical structures adopted by SPG and overall contour length consistent with a high molar mass.


Assuntos
Glucose , Schizophyllum , Xilose , Glucanos , Monossacarídeos
2.
Nat Prod Res ; 37(10): 1735-1741, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35945808

RESUMO

Intestinal glucose absorption plays a central role in the regulation of glucose plasmatic; however, current clinical management does not target the gut for treating diabetes. This study evaluated the effects of peel and pulp aqueous extract from Hylocereus lemairei on human enterocytes under high glucose concentration. Anti-hyperglycemic and antiobesity activities in vitro were also evaluated. Extracts did not cause cytotoxicity at 1 to 500 µg/mL. Moreover, they were effective in attenuating oxidative stress (DCFH-DA assay) and inflammation (•ON production) caused by high glucose. Intestinal enzymes (α- glucosidase and pancreatic lipase) were inhibited by pulp and peel extracts (>60% and >95%, respectively). Extracts exhibited a redox capacity superior to ascorbic and chlorogenic acids, presenting high phenolic content, mainly anthocyanins. The main compounds for both extracts were chlorogenic acid and naringin, and peel stood both qualitatively and quantitatively. Data suggest red Pitaya has potential as a new medicine for diabetes.


Assuntos
Antocianinas , Diabetes Mellitus , Humanos , Extratos Vegetais/farmacologia , Antioxidantes/farmacologia , alfa-Glucosidases , Glucose , Hipoglicemiantes/farmacologia
3.
J Environ Manage ; 319: 115677, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35816960

RESUMO

Metals are considered one of the biggest environmental problems, due to their toxicity and the complexity of removal. This study evaluated the bioaccumulation capacity of water contaminating metals by fungal isolates of Lentinus and Panus species, to elucidate the bioremediation processes of metal contaminated effluents. Initially, tests were performed with fungal isolates using a mixture of metals, aluminum, iron, copper, lead, chromium, nickel and zinc. Lentinus crinitus 154L.21 was the most promising fungus for the removal of metals in the mixture. Based on these data, the potential application of this fungus for the treatment of galvanic and tannery effluents was evaluated. For galvanic effluent, no detectable copper, chromium, and nickel was removed; however, for tannery effluents, reductions in aluminum concentrations from 204.1 to 3.7 mg L-1 (≅98% removal), chromium from 1199.6 to 20.4 mg L-1 (≅98% removal) and iron from 22.6 mg L-1 (100% removal) to an amount lower than the detection limit were observed. These data indicated that L. crinitus 154L.21 removes metals from industrial effluents, being an important route for bioremediation processes.


Assuntos
Metais Pesados , Níquel , Alumínio , Biodegradação Ambiental , Cromo/análise , Cobre , Florestas , Ferro , Metais , Metais Pesados/análise
4.
Int J Med Mushrooms ; 24(4): 31-42, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35695594

RESUMO

The main objective of this work was to evaluate whether Pleurotus albidus extract exerts influences on aorta artery tone by its antioxidant properties. The hearts and aortic arteries of male Wistar rats were removed for use in biochemical analysis and vascular reactivity. Both tissues were exposed to P. albidus extract at different concentrations for 30 min and were then exposed to a free radical generation system for 30 min. The extract reduced lipid peroxidation levels and increased catalase and glutathione peroxidase activity in cardiac tissue. In the aorta, P. albidus extract demonstrated a direct vasodilatory effect, which was associated with a reduction in nicotinamide adenine dinucleotide phosphate oxidase (NOX) activity and an increase in sulfhydryl levels and nitric oxide synthase (NOS) activity. Our findings suggest that P. albidus extract has regulatory potential on aorta arteries, regulating the balance of NOX/NOS enzymes and then influencing vessel tone. Further studies are needed to determine the protective mechanisms of the extract.


Assuntos
Antioxidantes , Vasodilatação , Animais , Antioxidantes/farmacologia , Aorta , Masculino , NADP/farmacologia , Óxido Nítrico , Óxido Nítrico Sintase/metabolismo , Pleurotus , Ratos , Ratos Wistar
5.
Antonie Van Leeuwenhoek ; 115(8): 1009-1029, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35678932

RESUMO

The genomes of two Penicillium strains were sequenced and studied in this study: strain 2HH was isolated from the digestive tract of Anobium punctatum beetle larva in 1979 and the cellulase hypersecretory strain S1M29, derived from strain 2HH by a long-term mutagenesis process. With these data, the strains were reclassified and insight is obtained on molecular features related to cellulase hyperproduction and the albino phenotype of the mutant. Both strains were previously identified as Penicillium echinulatum and this investigation indicated that these should be reclassified. Phylogenetic and phenotype data showed that these strains represent a new Penicillium species in series Oxalica, for which the name Penicillium ucsense is proposed here. Six additional strains (SFC101850, SFCP10873, SFCP10886, SFCP10931, SFCP10932 and SFCP10933) collected from the marine environment in the Republic of Korea were also classified as this species, indicating a worldwide distribution of this new taxon. Compared to the closely related strain Penicillium oxalicum 114-2, the composition of cell wall-associated proteins of P. ucsense 2HH shows five fewer chitinases, considerable differences in the number of proteins related to ß-D-glucan metabolism. The genomic comparison of 2HH and S1M29 highlighted single amino-acid substitutions in two major proteins (BGL2 and FlbA) that can be associated with the hyperproduction of cellulases. The study of melanin pathways shows that the S1M29 albino phenotype resulted from a single amino-acid substitution in the enzyme ALB1, a precursor of the 1,8-dihydroxynaphthalene (DHN)-melanin biosynthesis. Our study provides important knowledge towards understanding species distribution, molecular mechanisms, melanin production and cell wall biosynthesis of this new Penicillium species.


Assuntos
Celulase , Penicillium , Celulase/genética , Genômica , Melaninas/metabolismo , Penicillium/genética , Filogenia
6.
Bioprocess Biosyst Eng ; 44(6): 1321-1332, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33646354

RESUMO

The antimicrobial activity of the metabolites produced by Fusarium oxysporum PR-33 in submerged culture was evaluated against Gram-positive and Gram-negative bacteria and yeasts. Metabolites were determined by HPLC-DAD-MS/MS. An extract was obtained following the removal of mycelium by centrifugation and lyophilisation of the supernatant. The compounds in this extract demonstrated broad-spectrum antimicrobial action, with rates of inhibition between 60 and 80%, depending on the species and extract tested. The major compounds of the extracts were identified as fusarinolic acid and its isomer [56.9% flask extract (FE)] and 59.2% bioreactor extract (BE), dehydrofusaric acid (35.7% FE and 31.6% BE), and fusaric acid (6.5% FE and 1.1% BE). Fusaric acid has been shown to be responsible for antimicrobial activity. The cytotoxicity of the extracts was evaluated in culture of HEK-293 and SH-SY5Y animal cells and toxicity of these extracts was verified even in the lowest tested concentrations. Therefore, our results indicate that the compounds identified exhibit potential as antimicrobial agents.


Assuntos
Anti-Infecciosos , Fusarium/química , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Leveduras/crescimento & desenvolvimento , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Fusarium/metabolismo , Células HEK293 , Humanos
7.
J Food Biochem ; 44(8): e13247, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32478428

RESUMO

The purpose of this study was to investigate the effect of diet supplementations on biochemical, hematological, and redox metabolism parameters in streptozotocin-induced diabetic rats. Healthy male Wistar rats and streptozotocin-induced diabetic rats were provided diets supplemented with 20% of Pinus sp. sawdust or Pycnoporus sanguineus mycelium for 4 weeks. Diabetic rats treated with both Pinus sp. sawdust- and P. sanguineus mycelium-supplemented diets presented a significant decrease in non-HDL cholesterol of 38.43% and 33.53% and triglycerides of 70.03% and 69.81%, respectively, compared to diabetic control. As far as we know, this is the first report of a significant decrease in serum lipids attributed to these supplementations. Even though with the alterations in hematological and redox metabolism parameters related to these diet treatments, our data suggest that Pinus sp. sawdust and Pycnoporus sanguineus mycelium could be a useful a diet supplement to control diabetic dyslipidemia in animals. PRACTICAL APPLICATIONS: Pinus sp. sawdust is a residue from the wood industry that can be reused as a substrate to cultivate Pycnoporus sanguineus mycelium. Both species have specific and rich natural compounds. The results of the present study surprisingly showed that diets supplemented with the isolated substrate (Pinus sp. sawdust) and Pycnoporus sanguineus mycelium significantly decrease non-HDL cholesterol and triglycerides in induced diabetic animal model. These new natural approaches can be interesting to develop a nutraceutical to treat dyslipidemia.


Assuntos
Diabetes Mellitus Experimental , Pinus , Pycnoporus , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Lipídeos , Masculino , Micélio , Polyporaceae , Ratos , Ratos Wistar , Estreptozocina , Madeira
8.
Food Chem ; 297: 124988, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253285

RESUMO

Agaricus blazei, Auricularia fuscosuccinea and Pleurotus albidus mycelia were obtained in solid-state cultivation (SSC), using grains (brown rice, canjica corn and wheat) as raw material. Colonized grain flours were analysed for their nutritional, physical and physico-chemical characteristics and biological activity in vitro. Wheat flour with P. albidus showed higher values for protein (18.34 g/100 g), ergosterol (0.60 mg/g), mycelial biomass (183 mg/g) and total amino acids (58.34 mg/g). Corn flour with A. fuscosuccinea showed the highest total phenolic content (2.38 mg GAE/g), antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) (8.90 µmol TEAC/g) and 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) (16.52 µmol TEAC/g) assay. Wheat flour with P. albidus were more effective at inhibiting of pancreatic lipase (74.5%) and of α-glucosidase (98.2%). In conclusion, grains colonized by macrofungi mycelia through SSC can enrich the nutritional value and the biological activity of the flours, which presents a potential for functional foods.


Assuntos
Agaricus/fisiologia , Farinha/análise , Valor Nutritivo , Pleurotus/fisiologia , Aminoácidos/química , Antioxidantes/química , Biomassa , Ergosterol/análise , Lipase/antagonistas & inibidores , Lipase/metabolismo , Oryza/metabolismo , Fenóis/análise , Triticum/metabolismo , Zea mays/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
9.
Bioresour Technol ; 285: 121346, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31004946

RESUMO

The combination of hydrothermal pretreatment followed by delignification with imidazole was evaluated for the first time as a potential selective two-stage fractionation for elephant grass, aiming at obtaining pure fractions susceptible to conversion to high value-added products. In addition, the recovery of cellulose and hemicelluloses and enzymatic hydrolysis yield of pretreated elephant grass were evaluated. Hydrothermal pretreatment at 180 °C under non-isothermal conditions allowed obtaining a liquor rich mainly in xylo- and glucooligosaccharides, as well as pentoses. Subsequent treatment of the recovered solid fraction with imidazole at 140 °C for 182.5 min resulted in 83.8 wt% delignification and cellulose enrichment of 97.7 wt%. The solids obtained from the two-stage pretreatment process also permitted high glucan to glucose conversion through enzymatic hydrolysis using Cellic CTec2 (99.0 mol%) or an enzymatic complex of Penicillium echinulatum (96.3 mol%).


Assuntos
Lignina , Polissacarídeos , Hidrólise , Imidazóis
10.
J Biotechnol ; 295: 1-8, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30858107

RESUMO

Testing different pHs, dissolved oxygen concentrations and temperatures, plus the addition of inducers, to optimize ligninolytic enzyme activity, resulted in increased production of laccases, total peroxidases and manganese peroxidases on the order of 2.1-fold, 4.6-fold and 10-fold, respectively; laccases reached 6588 U/mL, total peroxidases reached 3533 U/mL and manganese peroxidase achieved 60 U/mL. Furthermore, an increase in laccase volumetric productivity and in its specific activity was verified. The addition of inducers, such as copper sulphate and manganese sulphate, improved enzymatic activity. In addition, a new previously unidentified laccase isoform was documented by zymography. The present work successfully increased the production of ligninolytic enzymes.


Assuntos
Reatores Biológicos , Proteínas Fúngicas , Lacase , Lignina/química , Marasmius/enzimologia , Peroxidases , Sulfato de Cobre/metabolismo , Estabilidade Enzimática , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Lacase/química , Lacase/metabolismo , Lignina/metabolismo , Sulfato de Magnésio/metabolismo , Peroxidases/química , Peroxidases/metabolismo
11.
Bioprocess Biosyst Eng ; 42(1): 83-92, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30264227

RESUMO

The present study evaluated 13 strains of yeast for ethanol and xylitol production from xylose. Among them, Spathaspora hagerdaliae UFMG-CM-Y303 produced ethanol yields (YP/S) of 0.25 g g- 1 and 0.39 g g- 1 under aerobic and microaerophilic conditions, respectively, from a mixture of glucose and xylose in flasks. A pH of 5.0 and an inoculum of 3.0 × 108 cells mL- 1r resulted in the highest ethanol yields. These conditions were tested in a bioreactor for fermenting a medium containing an enzymatic hydrolysate of sugarcane bagasse with 15.5 g L- 1 of glucose and 3 g L- 1 of xylose, and achieved a YP/S of 0.47 g g- 1, in relation to total available sugar. These results suggest that S. hagerdaliae UFMG-CM-Y303 has potential for use in second-generation ethanol studies.


Assuntos
Celulose/metabolismo , Etanol/química , Glucose/química , Saccharomycetales/metabolismo , Saccharum/metabolismo , Xilose/química , Bioengenharia/métodos , Biomassa , Reatores Biológicos , Meios de Cultura , Fermentação , Concentração de Íons de Hidrogênio , Cinética , Lignina/química , Saccharomyces cerevisiae/metabolismo , Xilitol/química
12.
Bioresour Technol ; 249: 1017-1024, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30045483

RESUMO

Elephant grass was subjected to steam explosion to enhance cellulose accessibility and convert it into ethanol. After catalyzed pretreatment at 190 °C for 5 min, enzymatic hydrolysis was carried out using high rate of solid loading combined with different enzyme dosages. Assays employing 20% (w/v) solids loading and an enzyme dosage of 20 FPU g-1 substrate led to a yield of 86.02 g glucose released per 100 g potential glucose in the water insoluble solids. This condition was selected to carry out the simultaneous saccharification and fermentation procedure through S. cerevisiae CAT-1, producing 42.25 g L-1 ethanol with a yield of 74.57% regard to the maximum theoretical. The liquor containing C5 and C6-sugars was successfully converted into lactic acid using L. buchneri NRRL B-30929, resulting in 13.35 g L-1 with a yield of 68.21% in relation to the maximum theoretical.


Assuntos
Etanol , Ácido Láctico , Saccharomyces cerevisiae , Fermentação , Hidrólise , Poaceae , Vapor
13.
Biomed Res Int ; 2018: 2859787, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30018977

RESUMO

Hyperglycaemia exacerbates the production of reactive oxygen species (ROS), contributing to the multiple complications associated with diabetes. Mitochondrial dysfunction is also known to be associated with diabetes. Therefore, the aim of this work was to study the effect of Pleurotus albidus extract on the mitochondrial dysfunction induced by hyperglycaemia in EA.hy926 endothelial cells. The results showed that P. albidus treatment prevented the increase in the activity of complex I of the electron transport chain and minimized the ROS production induced by hyperglycaemia. In addition, the extract minimized oxidative damage to lipids and proteins, caused an imbalance in the antioxidant enzyme activities of superoxide dismutase and catalase, and decreased the nitric oxide levels induced by hyperglycaemia. These data contribute to our understanding of the mitochondrial disorder induced by hyperglycaemia as well as establishing the conditions required to minimize these alterations.


Assuntos
Células Endoteliais/metabolismo , Hiperglicemia , Pleurotus , Humanos , Mitocôndrias , Estresse Oxidativo , Espécies Reativas de Oxigênio , Superóxido Dismutase
14.
Appl Biochem Biotechnol ; 186(4): 960-971, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29797299

RESUMO

Pretreatment of lignocellulosic biomass with ionic liquids (ILs) has been extensively studied, being regarded as one of the most promising methods for obtaining fermentable sugars. In this research, it was investigated the production of ethanol from sugars released from sugarcane bagasse pretreated with the ionic liquids [C4mim][OAc] and [C2mim][OAc], hydrolysed with Penicillium echinulatum enzymes and using Saccharomyces cerevisiae and Schizosaccharomyces pombe. Yields of about 43 and 56% of ethanol were observed for S. cerevisiae and biomass pretreated with [C2mim][OAc] and [C4mim][OAc], respectively. S. pombe yielded 52 and 78% ethanol for [C2mim][OAc] and [C4mim][OAc], respectively. These results indicate that S. pombe showed best performance for alcoholic fermentation from sugars released from pretreated biomass by ILs.


Assuntos
Celulose/química , Etanol/metabolismo , Líquidos Iônicos/química , Penicillium/crescimento & desenvolvimento , Saccharum/química , Schizosaccharomyces/crescimento & desenvolvimento
15.
Bioprocess Biosyst Eng ; 41(7): 1017-1028, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29616333

RESUMO

The potential to produce ethanol and xylitol from xylose by the macro basidiomycete Trametes membranacea was evaluated. All strains studied showed ethanol and xylitol production. The highest ethanol production of xylose was obtained by T. membranacea strain TM158/10 with 5.65 ± 0.21 g/L at pH 4 and 28 °C with 288 h of fermentation and 5.59 ± 0.05 g/L ethanol concentration at pH 5 and 24 °C with 360 h of fermentation. When the conversion was carried out using sugars generated from enzymatic hydrolysis of sugarcane bagasse, there were higher yields from 74 to 15% for ethanol and xylitol, respectively. Although the ethanol and xylitol production need to be optimized, this study showed for the first time the possibility of using T. membranacea for the simultaneous xylitol and ethanol production from pentose sugars, allowing for the possibility of using all released sugars during the hydrolysis of lignocelluloses.


Assuntos
Celulose/química , Etanol/metabolismo , Saccharum/química , Trametes/crescimento & desenvolvimento , Xilitol/biossíntese
16.
Bioresour Technol ; 211: 280-90, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27023383

RESUMO

The enzymatic hydrolysis of Pennisetum purpureum (elephant grass) was evaluated at high total solid levels (from 4% to 20% (w/v)) in a concomitant ball milling treatment in a rotating hydrolysis reactor (RHR). The greatest glucose yield was 20.17% when 4% (w/v) untreated biomass was employed. When sugars obtained from enzymatic hydrolysis were submitted to fermentation with Saccharomyces cerevisiae, the greatest ethanol yield was 22.61% when 4% (w/v) untreated biomass was employed; however, the highest glucose concentration (12.47g/L) was obtaining using 20% (w/v) solids and highest ethanol concentration (6.1g/L) was obtained using 16% (w/v) solids. When elephant grass was hydrolyzed in the rotating hydrolysis reactor, ethanol production was about double that was produced when the biomass was hydrolyzed in a static reactor (SR). These data indicate that it is possible to produce ethanol from elephant grass when milling treatment and enzymatic hydrolysis are performed at the same time.


Assuntos
Biocombustíveis , Biomassa , Etanol , Pennisetum , Etanol/análise , Etanol/metabolismo , Fermentação , Hidrólise , Pennisetum/química , Pennisetum/metabolismo , Saccharomyces cerevisiae
17.
Bioresour Technol ; 207: 46-51, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26868155

RESUMO

The aim of this study was to investigate the production profile of Pleurotus albidus and Pycnoporus sanguineus on different waste substrates containing natural phenolics, and also to investigate whether phenolic-rich substrates can improve the phenolic content of these macrofungi. The medium formulated with Pinus sp. sawdust (PSW) made possible the highest yields (2.62±0.73%) of P. sanguineus. However, the supplementation of PSW with apple waste (AW) resulted in better P. albidus yields (23.94±2.92%). The results indicated that the substrate composition affected macrofungi production, also the chemical composition and the presence of phenolic compounds in the production media influence phenolic content and antioxidant activity in macrofungi.


Assuntos
Antioxidantes/metabolismo , Pleurotus/crescimento & desenvolvimento , Pleurotus/metabolismo , Pycnoporus/crescimento & desenvolvimento , Pycnoporus/metabolismo , Fenóis/metabolismo
18.
Bioresour Technol ; 192: 228-37, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26038327

RESUMO

In this work, steam explosion was used a pretreatment method to improve the conversion of elephant grass (Pennisetum purpureum) to cellulosic ethanol. This way, enzymatic hydrolysis of vaccum-drained and water-washed steam-treated substrates was carried out with Penicillium echinulatum enzymes while Saccharomyces cerevisiae CAT-1 was used for fermentation. After 48 h of hydrolysis, the highest yield of reducing sugars was obtained from vaccum-drained steam-treated substrates that were produced after 10 min at 200 °C (863.42 ± 62.52 mg/g). However, the highest glucose yield was derived from water-washed steam-treated substrates that were produced after 10 min at 190 °C (248.34 ± 6.27 mg/g) and 200 °C (246.00 ± 9.60 mg/g). Nevertheless, the highest ethanol production was obtained from water-washed steam-treated substrates that were produced after 6 min at 200 °C. These data revealed that water washing is a critical step for ethanol production from steam-treated elephant grass and that pretreatment generates a great deal of water soluble inhibitory compounds for hydrolysis and fermentation, which were partly characterized as part of this study.


Assuntos
Etanol/metabolismo , Fermentação/fisiologia , Lignina/metabolismo , Pennisetum/metabolismo , Carboidratos , Celulase/metabolismo , Explosões , Temperatura Alta , Hidrólise , Penicillium/metabolismo , Saccharomyces cerevisiae/metabolismo , Vapor , Água/química
19.
Bioresour Technol ; 148: 86-90, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24045195

RESUMO

The production of cellulases and xylanases by Penicillium echinulatum in an airlift bioreactor was evaluated. In batch production, we tested media with isolated or associated cellulose and sorbitol. In fed-batch production, we tested cellulose addition at two different times, 30 h and 48 h. Higher liquid circulation velocities in the downcomer were observed in sorbitol 10 g L(-1) medium. In batch production, higher FPA (filter paper activity) and endoglucanase activities were obtained with cellulose (7.5 g L(-1)) and sorbitol (2.5 g L(-1)), 1.0 U mL(-1) (120 h) and 6.4 U m L(-1) (100 h), respectively. For xylanases, the best production condition was cellulose 10 g L(-1), which achieved 5.5 U mL(-1) in 64 h. The fed-batch process was favorable for obtaining xylanases, but not for FPA and endoglucanases, suggesting that in the case of cellulases, the inducer must be added early in the process.


Assuntos
Reatores Biológicos , Celulases/biossíntese , Endo-1,4-beta-Xilanases/biossíntese , Penicillium/enzimologia , Sorbitol/farmacologia , Ar , Técnicas de Cultura Celular por Lotes , Celulose/farmacologia , Penicillium/efeitos dos fármacos , Penicillium/crescimento & desenvolvimento
20.
Bioresour Technol ; 146: 597-603, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23973981

RESUMO

The development of more productive strains of microorganisms and processes that increase enzyme levels can contribute to the economically efficient production of second generation ethanol. To this end, cellulases and xylanases were produced with the S1M29 mutant strain of Penicillium echinulatum, using different concentrations of cellulose (20, 40, and 60 g L(-1)) in batch and fed-batch processes. The highest activities of FPase (8.3 U mL(-1)), endoglucanases (37.3 U mL(-1)), and xylanases (177 U mL(-1)) were obtained in fed-batch cultivation with 40 g L(-1) of cellulose. The P. echinulatum enzymatic broth and the commercial enzyme Cellic CTec2 were tested for hydrolysis of pretreated sugar cane bagasse. Maximum concentrations of glucose and xylose were achieved after 72 h of hydrolysis. Glucose yields of 28.0% and 27.0% were obtained using the P. echinulatum enzymatic extract and Cellic CTec2, respectively.


Assuntos
Técnicas de Cultura Celular por Lotes , Reatores Biológicos , Celulase/biossíntese , Celulose/química , Endo-1,4-beta-Xilanases/biossíntese , Penicillium/metabolismo , Biodegradação Ambiental , Etanol/química , Fermentação , Glucose/química , Hidrólise , Oxigênio/química , Saccharum , Fatores de Tempo , Xilose/química
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