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1.
Carbohydr Polym ; 261: 117883, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33766370

RESUMEN

A new biosorbent Ca-crosslinked pectin/lignocellulose nanofibers/chitin nanofibers (PLCN) was synthesized for cholesterol and bile salts adsorption from simulated intestinal fluid during gastric-intestinal passage. The physico-chemical properties of PLCN were studied using SEM, FTIR, XRD, DSC and BET. Before gastrointestinal passage, PLCN had an amorphous single-phase, compact structure formed via hydrogen and van der Waals bonds that revealed an irregular shape with the shriveled surface but watery condition and enzymatic digestion led to create a porous structure without destruction because of the water-insoluble nanofibers, therefore increasing the adsorption capacity. The maximum adsorption capacity reached 37.9 and 5578.4 mg/g for cholesterol and bile salts, respectively. Freundlich isotherm model indicated the reversible heterogeneous adsorption of both cholesterol and bile salts on PLCN. Further, their adsorption followed pseudo-second order kinetic model. These results suggest that PLCN has potential as a gastrointestinal-resistant biosorbent for cholesterol and bile salts adsorption applicable in medicine and food industry.


Asunto(s)
Ácidos y Sales Biliares/farmacocinética , Quitina/química , Colesterol/farmacocinética , Lignina/química , Nanofibras/química , Pectinas/química , Absorción Fisicoquímica/efectos de los fármacos , Adsorción/efectos de los fármacos , Quitina/farmacocinética , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/metabolismo , Humanos , Técnicas In Vitro , Cinética , Lignina/farmacocinética , Nanocompuestos/análisis , Nanocompuestos/química , Pectinas/farmacocinética
2.
J Pharm Pharmacol ; 72(12): 1879-1892, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32757489

RESUMEN

OBJECTIVES: This study was designed to profile the chemical information of Forsythiae Fructus (FF) and investigate the in-vivo FF-related xenobiotics, especially for lignans. METHODS: Rats were oral administrated of FF and pinoresinol-4-O-glucoside, respectively. Blood and urine samples were collected after ingestion, and xenobiotics was profiled by an UPLC/Qtof MS method. KEY FINDINGS: A total of 19 lignans were identified or tentatively characterized in FF, and 63 lignan-related xenobiotics were found in rat plasma and urine after ingestion of FF. It was found that lignans could be transformed into metabolites by furan ring opening, hydrogenation, demethylation, dehydration and phase II reactions (sulfation and glucuronidation). The whole metabolic behaviour of bisepoxylignan was revealed by evaluating the metabolism of pinoresinol-4-O-glucoside in vivo. It was found that the configuration of C-8/C-8' was retained after furan ring opening and metabolic reactions always occurred at position of C-3/C-4/C-5 or C-3'/C-4'/C-5'. Additionally, other types components in FF and in vivo were also characterized. CONCLUSIONS: This work revealed the in-vivo metabolism of FF, and reported the characteristic metabolic reactions of lignans for the first time. It was also provided the foundation for the further investigation on pharmacodynamic components of FF or TCMs containing FF.


Asunto(s)
Cromatografía Liquida , Forsythia , Lignina/farmacocinética , Extractos Vegetales/farmacocinética , Espectrometría de Masa por Ionización de Electrospray , Administración Oral , Animales , Biotransformación , Forsythia/química , Lignina/sangre , Lignina/aislamiento & purificación , Lignina/orina , Masculino , Extractos Vegetales/sangre , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/orina , Ratas Sprague-Dawley
3.
J Biomed Mater Res A ; 108(3): 770-783, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31794149

RESUMEN

Natural biopolymer nanoparticles (NPs), including nanocrystalline cellulose (CNC) and lignin, have shown potential as scaffolds for targeted drug delivery systems due to their wide availability, cost-efficient preparation, and anticipated biocompatibility. As both CNC and lignin can potentially cause complications in cell viability assays because of their ability to scatter the emitted light and absorb the assay reagents, we investigated the response of bioluminescent (CellTiter-Glo®), colorimetric (MTT® and AlamarBlue®), and fluorometric (LIVE/DEAD®) assays for the determination of the biocompatibility of the multimodal CNC and lignin constructs in murine RAW 264.7 macrophages and 4T1 breast adenocarcinoma cell lines. Here, we have developed multimodal CNC and lignin NPs harboring the radiometal chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid and the fluorescent dye cyanine 5 for the investigation of nanomaterial biodistribution in vivo with nuclear and optical imaging, which were then used as the model CNC and lignin nanosystems in the cell viability assay comparison. CellTiter-Glo® based on the detection of ATP-dependent luminescence in viable cells revealed to be the best assay for both nanoconstructs for its robust linear response to increasing NP concentration and lack of interference from either of the NP types. Both multimodal CNC and lignin NPs displayed low cytotoxicity and favorable interactions with the cell lines, suggesting that they are good candidates for nanosystem development for targeted drug delivery in breast cancer and for theranostic applications. Our results provide useful guidance for cell viability assay compatibility for CNC and lignin NPs and facilitate the future translation of the materials for in vivo applications.


Asunto(s)
Materiales Biocompatibles/metabolismo , Celulosa/metabolismo , Lignina/metabolismo , Nanopartículas/metabolismo , Animales , Materiales Biocompatibles/farmacocinética , Materiales Biocompatibles/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Celulosa/farmacocinética , Celulosa/toxicidad , Humanos , Lignina/farmacocinética , Lignina/toxicidad , Ratones , Nanopartículas/análisis , Nanopartículas/toxicidad , Células RAW 264.7 , Distribución Tisular
4.
Appl Environ Microbiol ; 84(18)2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-30030226

RESUMEN

Cell growth and polyhydroxyalkanoate (PHA) biosynthesis are two key traits in PHA production from lignin or its derivatives. However, the links between them remain poorly understood. Here, the transcription levels of key genes involved in PHA biosynthesis were tracked in Pseudomonas putida strain A514 grown on vanillic acid as the sole carbon source under different levels of nutrient availability. First, enoyl-coenzyme A (CoA) hydratase (encoded by phaJ4) is stress induced and likely to contribute to PHA synthesis under nitrogen starvation conditions. Second, much higher expression levels of 3-hydroxyacyl-acyl carrier protein (ACP) thioesterase (encoded by phaG) and long-chain fatty acid-CoA ligase (encoded by alkK) under both high and low nitrogen (N) led to the hypothesis that they likely not only have a role in PHA biosynthesis but are also essential to cell growth. Third, 40 mg/liter PHA was synthesized by strain AphaJ4C1 (overexpression of phaJ4 and phaC1 in strain A514) under low-N conditions, in contrast to 23 mg/liter PHA synthesized under high-N conditions. Under high-N conditions, strain AalkKphaGC1 (overexpression of phaG, alkK, and phaC1 in A514) produced 90 mg/liter PHA with a cell dry weight of 667 mg/liter, experimentally validating our hypothesis. Finally, further enhancement in cell growth (714 mg/liter) and PHA titer (246 mg/liter) was achieved in strain Axyl_alkKphaGC1 via transcription level optimization, which was regulated by an inducible strong promoter with its regulator, XylR-PxylA, from the xylose catabolic gene cluster of the A514 genome. This study reveals genetic features of genes involved in PHA synthesis from a lignin derivative and provides a novel strategy for rational engineering of these two traits, laying the foundation for lignin-consolidated bioprocessing.IMPORTANCE With the recent advances in processing carbohydrates in lignocellulosics for bioproducts, almost all biological conversion platforms result in the formation of a significant amount of lignin by-products, representing the second most abundant feedstock on earth. However, this resource is greatly underutilized due to its heterogeneity and recalcitrant chemical structure. Thus, exploiting lignin valorization routes would achieve the complete utilization of lignocellulosic biomass and improve cost-effectiveness. The culture conditions that encourage cell growth and polyhydroxyalkanoate (PHA) accumulation are different. Such an inconsistency represents a major hurdle in lignin-to-PHA bioconversion. In this study, we traced and compared transcription levels of key genes involved in PHA biosynthesis pathways in Pseudomonas putida A514 under different nitrogen concentrations to unveil the unusual features of PHA synthesis. Furthermore, an inducible strong promoter was identified. Thus, the molecular features and new genetic tools reveal a strategy to coenhance PHA production and cell growth from a lignin derivative.


Asunto(s)
Lignina/farmacocinética , Polihidroxialcanoatos/biosíntesis , Pseudomonas putida/crecimiento & desarrollo , Pseudomonas putida/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Vías Biosintéticas , Regulación Bacteriana de la Expresión Génica , Lignina/química , Regiones Promotoras Genéticas , Pseudomonas putida/enzimología , Pseudomonas putida/genética
5.
Appl Biochem Biotechnol ; 183(4): 1362-1374, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28528384

RESUMEN

This study aimed at developing low-cost, robust non-sterile fermentation processes for microbial lipid production from lignocellulose-derived sugars. Three representative oleaginous yeasts, Lipomyces tetrasporus (NRRL Y-11562), Rhodotorula toruloides (NRRL Y-1091), and Yarrowia lipolytica (NRRL YB-437), were tested for lipid production via non-sterile fermentation. Under optimal non-sterile conditions, all the tested strains had good performance on salt tolerance and lipid production. L. tetrasporus (NRRL Y-11562) gave the highest lipid titer of 12.79 g/L along with the depletion of both glucose and xylose, while Y. lipolytica (NRRL YB-437) showed the lowest lipid production and limited capability of xylose utilization. The key factors, including inoculation size, initial pH, and salt, all contributed to successful non-sterile fermentation. This study demonstrated that it is feasible to perform both sterile and non-sterile fermentation for lipid production using salt-containing lignocellulose-derived sugar streams.


Asunto(s)
Lignina , Lípidos/biosíntesis , Lipomyces/metabolismo , Sales (Química) , Yarrowia/metabolismo , Lignina/metabolismo , Lignina/farmacocinética , Sales (Química)/metabolismo , Sales (Química)/farmacocinética
6.
Artículo en Inglés | MEDLINE | ID: mdl-26680326

RESUMEN

3,4-Divanillyltetrahydrofuran is the main active ingredient of nettle root which can increase steroid hormones in the bloodstream for many of bodybuilders. To better understand its pharmacological activities, we need to determine its pharmacokinetic profiles. In this study, a rapid and sensitive ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method has been developed for the determination of 3,4-divanillyltetrahydrofuran in the plasma of rats. Chromatographic separation was performed on a C18 column at 40°C, with a gradient elution consisting of methanol and water containing 0.3% (v/v) formic acid at a flow rate of 0.8mL/min. The detection was performed using an electrospray triple-quadrupole MS/MS via positive ion multiple reaction monitoring mode. The lower limits-of-quantification determined were 0.5ng/mL. The intra- and inter-day precision (RSD%) was found to be within 15% and the accuracy (RE%) ranged from -4.0% to 7.0%. This simple yet sensitive method was fully validated and could be successfully applied to the study on pharmacokinetics of 3, 4-divanillyltetrahydrofuran.


Asunto(s)
Cromatografía Liquida/métodos , Furanos/farmacocinética , Lignina/farmacocinética , Espectrometría de Masas en Tándem/métodos , Animales , Área Bajo la Curva , Furanos/sangre , Semivida , Lignina/sangre , Masculino , Ratas , Estándares de Referencia , Reproducibilidad de los Resultados
7.
J Agric Food Chem ; 59(16): 8829-38, 2011 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-21732694

RESUMEN

The improvement of Zn fertilizers requires new techniques to evaluate their efficacy. In this paper, the (67)Zn stable isotope was used as tracer of several Zn-lignosulfonate complexes to study the foliar-applied Zn uptake and distribution behavior in the plant, compared with ZnEDTA. Navy bean plants ( Phaseolus vulgaris L.) were grown hydroponically in a Zn-free nutrient solution, and six modified lignosulfonates and EDTA complexed with (67)Zn were used in foliar application in the young leaves as Zn sources. Zinc isotopes in roots, stems, and sprayed and unsprayed leaves were determined by ICP-MS, and signal interferences caused by the compounds of the digested vegetal samples were corrected. The mathematical procedure of isotope pattern deconvolution allowed the minimization of the uncertainty in the measured molar fractions of Zn from fertilizer or from natural sources. Significant differences in Zn use and distribution were observed among the fertilizers when the calculated concentrations of Zn from the fertilizer were compared, whereas they were unnoticeable attending to the total Zn in plant tissues, usually determined at the conventional studies. By foliar spray, higher Zn uptake and mobilization to leaves and stems were achieved with (67)ZnEDTA than with (67)Zn-LS complexes. The ultrafiltered LS and phenolated LS showed slightly better ability to provide Zn to the bean plants than the other LS. The foliar-applied Zn use and distribution in the plant were related with the stability of the Zn-lignosulfonates complexes. Those presenting the lower stability versus pH, but the highest complexing capacity, were slightly more suitable to supply foliar-applied Zn to navy beans.


Asunto(s)
Lignina/análogos & derivados , Phaseolus/química , Semillas/química , Zinc/análisis , Fertilizantes , Lignina/administración & dosificación , Lignina/farmacocinética , Espectrometría de Masas , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Raíces de Plantas/química , Tallos de la Planta/química , Zinc/metabolismo , Zinc/farmacocinética , Isótopos de Zinc/administración & dosificación
8.
Bioresour Technol ; 98(7): 1494-500, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17161600

RESUMEN

Ammoxidation of kraft lignin was carried out in a Parr reactor using (15)NH(3) as the main nitrogen source. Reaction parameters were set up until a total nitrogen content of approximately 13 wt.% in lignin was achieved, in accordance with conditions of previous studies. Analytical tools such as FTIR, Py-GC/MS, and solid state NMR were used in this research. The nature of nitrogen bondings is discussed. The incorporation of the (15)N from ammoxidized lignin was followed in pumpkins (Zucchini cucurbita pepo L.) by means of (15)N emission spectroscopy.


Asunto(s)
Amoníaco/metabolismo , Cucurbita/metabolismo , Lignina/metabolismo , Lignina/farmacocinética , Isótopos de Nitrógeno/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Isótopos de Nitrógeno/farmacocinética , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier
9.
Crit Rev Biotechnol ; 24(2-3): 85-95, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15493527

RESUMEN

Bioremediation of wastewaters represents an important treatment methodology, especially when examined against the backdrop of ever-stricter legislation that is evolving in order to regulate effluent release into the environment. It has been reported that bioremediation specifically holds promise in solving environmental problems. Crucial questions surrounding the treatment of effluents include: efficiency of the process, economic feasibility, legal requirements, and the mechanisms involved in the remediation process. Of all these issues mentioned, the last requires special attention. This paper investigates these matters and focuses on techniques that are currently employed to determine the efficiency of bioremediation and mechanisms involved therein. The physiological significance of biosorption is also examined, as this subject has not been fully addressed in previous publications.


Asunto(s)
Basidiomycota/metabolismo , Reactores Biológicos/microbiología , Microbiología Industrial/métodos , Residuos Industriales/prevención & control , Papel , Contaminantes Químicos del Agua/farmacocinética , Purificación del Agua/métodos , Biodegradación Ambiental , Biotecnología/métodos , Biotecnología/tendencias , Microbiología Industrial/tendencias , Lignina/farmacocinética , Microbiología del Agua , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminación del Agua/prevención & control
10.
Appl Biochem Biotechnol ; 105 -108: 615-28, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12721440

RESUMEN

In addition to fermentable sugars, dilute-acid hydrolysates of lignocellulose contain compounds that inhibit fermenting microorganisms, such as Saccharomyces cerevisiae. Previous results show that phenolic compounds and furan aldehydes, and to some extent aliphatic acids, act as inhibitors during fermentation of dilute-acid hydrolysates of spruce. Treatment of lignocellulose hydrolysates with alkali, usually in the form of overliming to pH 10.0, has been frequently employed as a detoxification method to improve fermentability. A spruce dilute-acid hydrolysate was treated with NaOH in a factorial design experiment, in which the pH was varied between 9.0 and 12.0, the temperature between 5 and 80 degrees C, and the time between 1 and 7 h. Already at pH 9.0, >25% of the glucose was lost when the hydrolysate was treated at 80 degrees C for 1 h. Among the monosaccharides, xylose was degraded faster under alkaline conditions than the hexoses (glucose, mannose, and galactose), which, in turn, were degraded faster than arabinose. The results suggest that alkali treatment of hydrolysates can be performed at temperatures below 30 degrees C at any pH between 9.0 and 12.0 without problems with sugar degradation or formation of inhibiting aliphatic acids. Treatment with Ca(OH)2 instead of NaOH resulted in more substantial degradation of sugars. Under the harsher conditions of the factorial design experiment, the concentrations of furfural and 5-hydroxymethylfurfural decreased while the total phenolic content increased. The latter phenomenon was tentatively attributed to fragmentation of soluble aromatic oligomers in the hydrolysate. Separate phenolic compounds were affected in different ways by the alkaline conditions with some compounds showing an increase in concentration while others decreased. In conclusion, the conditions used for detoxification with alkali should be carefully controlled to optimize the positive effects and minimize the degradation of fermentable sugars.


Asunto(s)
Celulosa/farmacocinética , Combustibles Fósiles , Inactivación Metabólica , Lignina/farmacocinética , Hidróxido de Calcio , Celulosa/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Electrólitos/aislamiento & purificación , Fermentación , Concentración de Iones de Hidrógeno , Hidrólisis , Indicadores y Reactivos , Lignina/aislamiento & purificación , Picea/metabolismo , Saccharomyces cerevisiae/metabolismo , Hidróxido de Sodio , Termodinámica
11.
Appl Biochem Biotechnol ; 105 -108: 141-53, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12721481

RESUMEN

The filtrate from steam-pretreated poplar was analyzed to identify degradation compounds. The effect of selected compounds on growth and ethanolic fermentation of the thermotolerant yeast strain Kluyveromyces marxianus CECT 10875 was tested. Several fermentations on glucose medium, containing individual inhibitory compounds found in the hydrolysate, were carried out. The degree of inhibition on yeast strain growth and ethanolic fermentation was determined. At concentrations found in the prehy-drolysate, none of the individual compounds significantly affected the fermentation. For all tested compounds, growth was inhibited to a lesser extent than ethanol production. Lower concentrations of catechol (0.96 g/L) and 4-hydroxybenzaldehyde (1.02 g/L) were required to produce the 50% reduction in cell mass in comparison to other tested compounds.


Asunto(s)
Celulosa/farmacocinética , Etanol/metabolismo , Kluyveromyces/fisiología , Lignina/farmacocinética , Benzaldehídos/farmacocinética , Biodegradación Ambiental , Catecoles/farmacocinética , Medios de Cultivo , Fermentación , Glucosa/metabolismo , Calor , Cinética , Kluyveromyces/crecimiento & desarrollo , Termodinámica
12.
J Androl ; 23(6): 889-98, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12399536

RESUMEN

Lignin-derived macromolecules (LDMs) are biologically active compounds that affect a variety of cell-to-cell interactions including the inhibition of fertilization and embryo development in a number of nonmammalian species. The effect of ligno-sulfonic acid (LSA), a highly sulfonated LDM, on cynomolgus macaque sperm-oocyte interaction was evaluated with a zona pellucida binding assay and by in vitro fertilization (IVF). Sperm were treated with LSA (1.5 mg/mL) either before washing or after capacitation. Capacitation included centrifugation through 80% Percoll followed by 2 consecutive washes with medium, overnight incubation, and activation with dibutyryl cyclic adenosine monophosphate and caffeine. The zona binding assay was performed using immature oocytes that had adhered to the center of glass "binding chambers." The number of capacitated sperm that attached to the zona over a 3-minute period was recorded. Sperm attachment was significantly inhibited by LSA as compared to controls whether treatment occurred after capacitation (92.5%; P <.001) or before washing (82.5%; P <.001). When sperm were treated similarly with fucoidin, a sulfated polysaccharide known to inhibit sperm-oocyte interaction, sperm-zona binding was significantly inhibited by postcapacitation treatment but not by prewash treatment. Treatment of sperm with LSA consistently blocked fertilization over 4 IVF cycles both before washing and after capacitation. Fertilization rate for controls was 65% +/- 17%. No LSA-treated sperm were observed on the surface of lightly rinsed oocytes after 4 hours of coincubation. Localization of biotinylated LSA showed labeling over the entire sperm surface with the greatest intensity observed over the head and midpiece. LSA treatment had no effect on the percentage of motile sperm or quality of sperm motility. Due to the antifertility properties of this nontoxic molecule, LSA appears to have potential as a vaginal contraceptive.


Asunto(s)
Fertilización In Vitro , Fertilización/efectos de los fármacos , Lignina/análogos & derivados , Lignina/administración & dosificación , Oocitos/fisiología , Capacitación Espermática , Espermatozoides/fisiología , Animales , Esquema de Medicación , Femenino , Lignina/farmacocinética , Macaca fascicularis , Masculino , Interacciones Espermatozoide-Óvulo , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo , Distribución Tisular , Zona Pelúcida/fisiología
13.
Appl Biochem Biotechnol ; 98-100: 563-75, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12018282

RESUMEN

Acid hydrolysis of lignocellulose to hydrolysates intended for production of fuel ethanol results in the formation of byproducts in addition to fermentable sugars. Some of the byproducts, such as phenolic compounds and furan aldehydes, are inhibitory to the fermenting microorganism. Detoxification of the hydrolysates may be necessary for production of ethanol at a satisfactory rate and yield. The lignin residue obtained after hydrolysis is a material with hydrophobic properties that is produced in large amounts as a byproduct within an ethanol production process based on lignocellulosic raw materials. We have explored the possibility of using this lignin residue for detoxification of spruce dilute-acid hydrolysates prior to fermentation with Saccharomyces cerevisiae. Three dilute-acid hydrolysates of spruce were treated with lignin residue, which in all cases resulted in improved fermentability in terms of productivity and yield of ethanol. The effect was improved by washing the lignin before treatment, by using larger amounts of lignin in the treatment, and by performing the treatment at low temperature. Treatment with the lignin residue removed up to 53% of the phenolic compounds and up to 68% of the furan aldehydes in a spruce dilute-acid hydrolysate. A larger fraction of furfural was removed compared to the less hydrophobic 5-hydroxymethylfurfural.


Asunto(s)
Celulosa/farmacocinética , Combustibles Fósiles , Lignina/farmacocinética , Biotecnología/métodos , Fermentación , Inactivación Metabólica , Saccharomyces cerevisiae/crecimiento & desarrollo , Saccharomyces cerevisiae/metabolismo
14.
Appl Biochem Biotechnol ; 98-100: 663-77, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12018291

RESUMEN

Four soil fungi able to grow under low oxygenation conditions were selected and used in studies to determine the production of enzymes that promote the degradation of lignocellulosic materials. The capacity of these fungi to ferment such materials was also investigated. The fungi were grown in sugarcane bagasse and sawdust at final concentrations of 4 and 10%, as the carbon sources. The strains were cultivated under microaerophilic and combined conditions of oxygenation (aerobic followed by microaerophilic conditions). The results obtained with the basidiomycete specie, Trichocladium canadense, Geotrichum sp., and Fusarium sp. suggest that they prefer lower oxygen concentration for growth and enzyme production. Lignocellulolytic activities were detected in all strains but varied with the carbon source used. The highest levels of these activities were produced by the Basidiomycete specie and Fusarium sp. Ethanol and other nongaseous fermentation products were detected following high-performance liquid chromatography analysis using a supelcogel C-610H column, demonstrating the fermentative capability of these strains. In view of their ability to produce enzymes necessary for the breakdown of lignocellulosic materials and to utilize most of the degradation products for growth, these strains have a great potential for biotechnological application.


Asunto(s)
Celulosa/farmacocinética , Hongos/crecimiento & desarrollo , Fusarium/crecimiento & desarrollo , Geotrichum/crecimiento & desarrollo , Glicósido Hidrolasas/metabolismo , Lignina/farmacocinética , Biomasa , Medios de Cultivo , Fermentación , Hongos/enzimología , Fusarium/enzimología , Geotrichum/enzimología , Cinética , Consumo de Oxígeno , Especificidad por Sustrato
15.
Ukr Biokhim Zh (1978) ; 70(1): 68-74, 1998.
Artículo en Ucraniano | MEDLINE | ID: mdl-9848143

RESUMEN

The peculiarities of lignocellulose biotransformation by white-rot fungi Pleurotus floridae and Phellinus igniarius during their solid-state fermentation of wastes of oil-bearing crops processing has been studied. The dynamics of oil-bearing crops processing wastes bioconversion has been studied. It has been marked that P. floridae utilized 20% cellulose and lignin during 9 weeks and 40% lignin and 30% cellulose during all period of fermentation (19 weeks). The fungus P. igniarius utilized mainly cellulose (40% cellulose and 24% lignin in 19 weeks). Lignin-degradative capacity of P. floridae (KL = 0.57) and P. igniarius (KL = 0.34) has been quantitatively estimated. The degradation of plant biopolimers corresponded to the production of ligninolytic (laccase, Mn(2+)-dependent peroxidase,) and cellulolytic (CMC-cellulase) enzymes. The component and isoenzyme content of ligninolytic enzyme complex of fungi Pleurotus floridae and Phellinus igniarius has been determined.


Asunto(s)
Basidiomycota/metabolismo , Celulosa/farmacocinética , Isoenzimas/metabolismo , Lignina/farmacocinética , Pleurotus/metabolismo , Biotransformación
17.
Planta Med ; 58(6): 520-3, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1336605

RESUMEN

Structural transformation of arctiin and tracheloside, major components of seeds of Arctium lappa and Carthamus tinctorius, were investigated using rat gastric juice (pH 1.2-1.5) and rat large intestinal flora in vitro. Quantitative analysis of lignans and their metabolites was carried out by high performance liquid chromatography. Both lignans were stable in rat gastric juice and arctiin was rapidly transformed to arctigenin in rat large intestinal flora, followed by conversion to the major metabolite, 2-(3",4"-dihydroxybenzyl)-3-(3',4'-dimethoxybenzyl)-butyrolactone. On the other hand, tracheloside also decreased dependently with time and was converted to trachelogenin and its major metabolite, 2-(3",4"-dihydroxybenzyl)-3-(3',4'-dimethoxybenzyl)-2-hydroxybutyrola ctone. These experiments suggest that in the course of metabolism of lignans, firstly a cleavage of the glycosidic bond occurred and then demethylation of the phenolic methoxy group in the alimentary tract followed.


Asunto(s)
4-Butirolactona/análogos & derivados , Furanos/farmacocinética , Glucósidos/farmacocinética , Lignina/farmacocinética , Plantas Medicinales , 4-Butirolactona/farmacocinética , Animales , Biotransformación , Furanos/aislamiento & purificación , Glucósidos/aislamiento & purificación , Lignanos , Lignina/aislamiento & purificación , Masculino , Plantas Medicinales/química , Ratas , Ratas Wistar
18.
Appl Environ Microbiol ; 58(10): 3225-32, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1444360

RESUMEN

White rot basidiomycetes were able to biodegrade styrene (1-phenylethene) graft copolymers of lignin containing different proportions of lignin and polystyrene [poly(1-phenylethylene)]. The biodegradation tests were run on lignin-styrene copolymerization products which contained 10.3, 32.2, and 50.4% (wt/wt) lignin. The polymer samples were incubated with the white rot fungi Pleurotus ostreatus, Phanerochaete chrysosporium, and Trametes versicolor and the brown rot fungus Gloeophyllum trabeum. White rot fungi degraded the plastic samples at a rate which increased with increasing lignin content in the copolymer sample. Both polystyrene and lignin components of the copolymer were readily degraded. Polystyrene pellets were not degradable in these tests. Degradation was verified for both incubated and control samples by weight loss, quantitative UV spectrophotometric analysis of both lignin and styrene residues, scanning electron microscopy of the plastic surface, and the presence of enzymes active in degradation during incubation. Brown rot fungus did not affect any of the plastics. White rot fungi produced and secreted oxidative enzymes associated with lignin degradation in liquid media during incubation with lignin-polystyrene copolymer.


Asunto(s)
Basidiomycota/metabolismo , Lignina/metabolismo , Poliestirenos/metabolismo , Basidiomycota/enzimología , Biodegradación Ambiental , Biotransformación , Lignina/farmacocinética , Microscopía Electrónica de Rastreo , Peroxidasas/metabolismo , Poliestirenos/farmacocinética
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