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1.
Talanta ; 190: 167-173, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30172494

RESUMEN

Although arsenic (As) toxicity in soil vary depending on its chemical forms and oxidation states, regulatory limits for this compartment rely on total As content. Conventional methods of total As determination are expensive and time-consuming. The development of predictive techniques might enable a speditive assessment of As contamination in those scenarios, such as thermal spring sites, where exposure to the metalloid poses a threat to human health. The objective of this study was to assess the suitability of Visible Near Infrared spectrophotometry for predicting the total As content in highly calcareous thermal spring soils and the same aim was pursued for those elements (i.e. Al, Fe and Mn) the chemistry of which is tightly connected with that of As. A Partial Least Square approach, including cross-validation and external independent test, was used to relate the concentrations of the target elements to spectral data. The most accurate prediction was found for As with Pearson's coefficient, RMSE, RPD and SEP being equal to 0.94, 69.65, 2.9 and 66.99, respectively. Less accurate predictions were found for Al (r = 0.88; RMSE = 11014; RPD = 1.96; SEP = 11014), Fe (r = 0.93; RMSE = 6921.1; RPD = 2.45; SEP = 6462.4), and Mn (r = 0.92; RMSE = 542.01; RPD = 2.43; SEP = 529.79).

2.
J Hazard Mater ; 283: 35-43, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25261758

RESUMEN

Bacterial and fungal biodiversity throughout different biostimulation and bioaugmentation treatments applied to an industrial creosote-polluted soil were analyzed by means of polyphasic approach in order to gain insight into the microbial community structure and dynamics. Pyrosequencing data obtained from initial creosote polluted soil (after a biopiling step) revealed that Alpha and Gammaproteobacteria were the most abundant bacterial groups, whereas Fusarium and Scedosporium were the main fungal genera in the contaminated soil. At the end of 60-days laboratory scale bioremediation assays, pyrosequencing and DGGE data showed that (i) major bacterial community shifts were caused by the type of mobilizing agent added to the soil and, to a lesser extent, by the addition of lignocellulosic substrate; and (ii) the presence of the non-ionic surfactant (Brij 30) hampered the proliferation of Actinobacteria (Mycobacteriaceae) and Bacteroidetes (Chitinophagaceae) and, in the absence of lignocellulosic substrate, also impeded polycyclic aromatic hydrocarbons (PAHs) degradation. The results show the importance of implementing bioremediation experiments combined with microbiome assessment to gain insight on the effect of crucial parameters (e.g. use of additives) over the potential functions of complex microbial communities harbored in polluted soils, essential for bioremediation success.


Asunto(s)
Creosota/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Microbiología del Suelo , Contaminantes del Suelo/análisis , Bacterias/clasificación , Biodegradación Ambiental , Biodiversidad , ADN Espaciador Ribosómico/genética , Electroforesis en Gel de Gradiente Desnaturalizante , Hongos/clasificación , Industrias , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Suelo/química , Tensoactivos/química
3.
J Hazard Mater ; 260: 975-83, 2013 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-23892164

RESUMEN

Aim of this work was to investigate the ability of Lentinus (Panus) tigrinus to degrade and detoxify a chlorobenzoate (CBA) mixture composed of mono-, di- and tri-chlorinated isomers. The degradation process was investigated as a function of both the growing medium (i.e. low N Kirk's and malt extract-glucose medium) and cultivation conditions (i.e. stationary and shaken cultures). The majority of CBAs were quantitatively degraded within the early 15 d from spiking with the notable exception of the double ortho-chlorinated compounds, 2,6-di-, 2,3,6-tri- and 2,4,6-tri-CBA. Analysis of the degradation intermediates indicated the occurrence of side chain reduction, hydroxylation and methylation reactions. Although CBAs stimulated laccase production, in vitro experiments with a purified L. tigrinus laccase isoenzyme demonstrated its inability to participate in the initial attack on CBAs even in the presence of redox mediators; similar results were found with a Mn-peroxidase isoenzyme. Conversely, prompt degradation was observed upon 1h incubation of CBAs with a purified microsomal fraction containing cytochrome P-450 monooxygenase. The nature of some reaction products (i.e. hydroxylated derivatives), the dependency of the reaction on NADPH and its susceptibility to either CO or piperonyl butoxide inhibition confirmed the involvement of L. tigrinus cytochrome P-450 in the early steps of CBA degradation.


Asunto(s)
Clorobenzoatos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Lentinula/metabolismo , Purificación del Agua/métodos , Aliivibrio fischeri/metabolismo , Biodegradación Ambiental , Biomasa , Cloro/química , Clorobenzoatos/análisis , Medios de Cultivo/metabolismo , Lacasa/metabolismo , Luminiscencia , Microsomas/metabolismo , Oxígeno/química , Peroxidasas , Especificidad por Sustrato , Pruebas de Toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo
4.
J Appl Microbiol ; 114(6): 1750-62, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23414514

RESUMEN

AIMS: To investigate the effect of support and growth medium (GM) on Pleurotus ostreatus biofilm production, specific metabolic activity (SMA) and ultrastructure. METHODS AND RESULTS: Biofilms were developed on membranes covering a broad range of surface properties and, due to the applicative implications of mixed biofilms, on standard bacterial GM in stationary and shaken culture. Hydrophilic (glass fibre, Duran glass and hydroxyapatite) and mild hydrophobic (polyurethane, stainless steel, polycarbonate, nylon) supports were more adequate for biofilm attachment than the hydrophobic Teflon. Among the GM, sucrose-asparagine (SA) was more conducive to biofilm production than Luria-Bertani and M9. GM was more influential than support type on biofilm ultrastructure, and a high compactness was evident in biofilms developed on SA. Biofilms on Duran glass were more efficient than planktonic cultures in olive-mill wastewater treatment. CONCLUSIONS: The main effects of support and GM variables and their binary interactions on both biofilm production and SMA were all highly significant (P < 0·001): thus, the magnitude of the effect of each variable strongly depended on the level of the other one. SIGNIFICANCE AND IMPACT OF THE STUDY: There is a lack of basic information regarding physiology and ultrastructure of P. ostreatus biofilms. To our knowledge, this is the first attempt to fill this gap, thus representing a basis for future studies.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Pleurotus/fisiología , Medios de Cultivo , Vidrio , Interacciones Hidrofóbicas e Hidrofílicas , Plancton , Pleurotus/metabolismo , Pleurotus/ultraestructura , Acero Inoxidable , Propiedades de Superficie
5.
J Hazard Mater ; 248-249: 407-14, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23416485

RESUMEN

High recalcitrant characteristics and low bioavailability rates due to aging processes can hinder high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs) bioremediation in real industrial polluted soils. With the aim of reducing the residual fraction of total petroleum hydrocarbons (TPH) and (HMW-PAHs) in creosote-contaminated soil remaining after a 180-d treatment in a pilot-scale biopile, either biostimulation (BS) of indigenous microbial populations with a lignocellulosic substrate (LS) or fungal bioaugmentation with two strains of white-rot fungi (WRF) (i.e., Trametes versicolor and Lentinus tigrinus) were comparatively tested. The impact of bivalent manganese ions and two mobilizing agents (MAs) (i.e., Soybean Oil and Brij 30) on the degradation performances of biostimulated and bioaugmented microcosms was also compared. The results reveal soil colonization by both WRF strains was clearly hampered by an active native soil microbiota. In fact, a proper enhancement of native microbiota by means of LS amendment promoted the highest biodegradation of HMW-PAHs, even of those with five aromatic rings after 60 days of treatment, but HMW-PAH-degrading bacteria were specifically inhibited when non-ionic surfactant Brij 30 was amended. Effects of bioaugmentation and other additives such as non-ionic surfactants on the degrading capability of autochthonous soil microbiota should be evaluated in polluted soils before scaling up the remediation process at field scale.


Asunto(s)
Lentinula/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Trametes/metabolismo , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Biodegradación Ambiental , Residuos Industriales , Lignina/farmacología , Manganeso/farmacología , Polidocanol , Polietilenglicoles/farmacología , ARN Bacteriano/genética , ARN de Hongos/genética , ARN Ribosómico 16S/genética , Aceite de Soja/farmacología , Tensoactivos/farmacología
6.
J Hazard Mater ; 186(2-3): 1263-70, 2011 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-21177025

RESUMEN

The ability of Lentinus tigrinus to grow and to degrade persistent aromatic hydrocarbons in aged contaminated soil was assessed in this study. L. tigrinus extensively colonized the soil; its degradation activity after 60 d incubation at 28°C, however, was mostly limited to dichloroaniline isomers, polychlorinated benzenes and diphenyl ether while the fungus was unable to deplete 9,10-anthracenedione and 7-H-benz[DE]anthracene-7-one which were the major soil contaminants. Although clean-up levels were limited, both density of cultivable heterotrophic bacteria and richness of the resident bacterial community in L. tigrinus microcosms (LtM) increased over time to a significantly larger extent than the respective amended incubation controls (1.9×10(9) CFU g(-1) vs. 1.0×10(9) CFU g(-1) and 37 vs. 16, respectively). Naphthalene- and catechol 2,3-dioxygenase gene copy numbers, however, decreased over time at a higher rate in LtM than in incubation controls likely due to a higher stimulation on heterotrophs than xenobiotics-degrading community members.


Asunto(s)
Biodegradación Ambiental , Lentinula/química , Microbiología del Suelo , Contaminantes del Suelo/análisis , Suelo/análisis , Catecol 2,3-Dioxigenasa/genética , Catecol 2,3-Dioxigenasa/metabolismo , ADN de Hongos/genética , ADN de Hongos/aislamiento & purificación , Descontaminación , Ácidos Grasos/análisis , Dosificación de Gen , Lentinula/genética , Lentinula/crecimiento & desarrollo , Metales Pesados/análisis , Micelio/crecimiento & desarrollo , Fosfolípidos/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
7.
Bioresour Technol ; 100(13): 3395-402, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19303284

RESUMEN

Olive-mill wastewater (OMW) was investigated for its suitability to serve as a medium for lipase production by Candida cylindracea NRRL Y-17506. The OMW that best supported enzyme production was characterized by low COD and low total sugars content. In shake flask batch cultures, OMW supplementation with 2.4 g l(-1) NH(4)Cl and 3 g l(-1) olive oil led to an enzyme activity of about 10 U ml(-1). The addition of glucose or malt extract and supplements containing organic N (e.g., peptone, yeast extract) either depressed or did not affect the enzyme production. Further experiments were then performed in a 3-l stirred tank reactor to assess the impact of medium pH and stirring speed on the yeast enzyme activity. The lipase activity was low (1.8 U ml(-1)) when the pH was held constant at 6.5, significantly increased (18.7 U ml(-1)) with uncontrolled pH and was maximum (20.4 U ml(-1)) when the pH was let free to vary below 6.5. A stirring regime, that varied depending on the dissolved oxygen concentration in the medium, both prevented the occurrence of anoxic conditions during the exponential growth phase and enabled good lipase production (i.e., 21.6 U ml(-1)) and mean volumetric productivity (i.e., 123.5 Ul(-1)h(-1)).


Asunto(s)
Reactores Biológicos , Candida/enzimología , Candida/metabolismo , Microbiología Industrial/métodos , Lipasa/metabolismo , Biomasa , Biotecnología/métodos , Medios de Cultivo , Industria de Alimentos , Glucosa/química , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Residuos Industriales , Aceite de Oliva , Oxígeno/metabolismo , Aceites de Plantas , Eliminación de Residuos Líquidos , Administración de Residuos
8.
Biotechnol Bioeng ; 101(2): 273-85, 2008 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-18727031

RESUMEN

The impact of several mobilizing agents (MAs) (i.e., soybean oil, Tween-20, Tween-80, olive-oil mill wastewaters, and randomly methylated beta-cyclodextrins) on the degradation performances of the white-rot fungi Irpex lacteus and Pleurotus ostreatus was comparatively assessed in a soil spiked with a mixture of seven polycyclic aromatic hydrocarbons (PAHs). Among the different MAs, soybean oil best supported the growth of both fungi that was twice that observed in soil in the absence of MAs. In addition, soybean oil positively affected PAH degradation by both fungi. In this case, the total weight of organic contaminants (TWOC) was lower than that in the absence of MAs (57.7 vs. 201.3 and 26.3 vs. 160.4 mg kg(-1) with I. lacteus and P. ostreatus, respectively). On the other hand, the number of cultivable heterotrophic bacteria was significantly lower in the soil with soybean oil augmented with either one of the two fungi (5.21 vs. 8.71 and 0.22 vs. 0.51 x 10(7) CFU g(-1) soil with I. lacteus and P. ostreatus, respectively). The effect of soybean oil was confirmed by denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA genes that showed a general decrease in biodiversity. The impact of the other MAs on bacterial diversity was either slightly negative or positive in incubation controls. Both richness and Shannon-Weaver index decreased upon treatment with P. ostreatus. Moreover, with this fungus the composition of the indigenous bacteria was not significantly affected by the type of MA used. By contrast, both indices increased in soil with I. lacteus in the presence of randomly methylated beta-cyclodextrins (39 vs. 33 and 1.43 vs. 1.26, respectively) and soybean oil (19 vs. 5 and 1.01 vs. 0.65, respectively).


Asunto(s)
Bacterias/crecimiento & desarrollo , Pleurotus/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Aceite de Soja/química , Análisis de Varianza , Bacterias/genética , Biodegradación Ambiental , Biodiversidad , ADN Bacteriano/genética , Electroforesis en Gel de Campo Pulsado , Peroxidasas/metabolismo , Pleurotus/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa , Polisorbatos/química
10.
Tech Coloproctol ; 10(4): 303-7, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17115319

RESUMEN

BACKGROUND: The use of laparoscopy for colorectal cancer resection is still controversial. METHODS: We prospectively analyzed the outcome of minimally invasive resection for colorectal cancer, performed at our institution from 1998, when laparoscopic surgery became the treatment of choice for colorectal cancer, until 2004. All patients undergoing elective resection were assessed in terms of perioperative results (duration of surgery, number of lymph nodes removed, length of specimen, rate of conversion, complications) and survival. Patients were assessed yearly with follow-up visits and telephone interviews. RESULTS: In the study period, 302 patients (mean age 66.1 years; range, 32-93 years) underwent 114 left hemicolectomies, 108 low anterior resections, 61 right hemicolectomies, 12 Miles procedures, 4 subtotal colectomies, and 3 transverse colon resections. Surgery took an average of 226 minutes (SD=71 min). The number of lymph nodes removed was 14+/-8. The conversion rate was 10%; most of the conversions were due to locally advanced cancer (15 cases) and bowel distension (7 cases). Fifteen anastomotic leaks were observed (5%). Twenty patients needed reoperation and two died: one of septic shock due to an anastomotic leak; the other of electrolyte imbalance and dehydration after peritonitis due to a bowel loop injury. Follow-up was available for 91% of patients. Cancer-related survival curves showed a 90% survival for stage II, 85% for stage III, and 10% for stage IV disease, 30 months after surgery. CONCLUSIONS: Minimally invasive laparoscopic resection for colorectal cancer enables an oncologically adequate resection with complication and survival rates that are no worse than are to be expected after traditional open surgery. Locally advanced tumor and bowel distension are the most frequent reasons for conversion to open surgery.


Asunto(s)
Adenocarcinoma/cirugía , Colectomía/métodos , Neoplasias del Colon/cirugía , Laparoscopía , Neoplasias del Recto/cirugía , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Tasa de Supervivencia , Resultado del Tratamiento
11.
Appl Environ Microbiol ; 72(1): 28-36, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16391021

RESUMEN

Nine fungal strains isolated from an aged and heavily contaminated soil were identified and screened to assess their degradative potential. Among them, Allescheriella sp. strain DABAC 1, Stachybotrys sp. strain DABAC 3, and Phlebia sp. strain DABAC 9 were selected for remediation trials on the basis of Poly R-478 decolorization associated with lignin-modifying enzyme (LME) production. These autochthonous fungi were tested for the abilities to grow under nonsterile conditions and to degrade various aromatic hydrocarbons in the same contaminated soil. After 30 days, fungal colonization was clearly visible and was confirmed by ergosterol determination. In spite of subalkaline pH conditions and the presence of heavy metals, the autochthonous fungi produced laccase and Mn and lignin peroxidases. No LME activities were detected in control microcosms. All of the isolates led to a marked removal of naphthalene, dichloroaniline isomers, o-hydroxybiphenyl, and 1,1'-binaphthalene. Stachybotrys sp. strain DABAC 3 was the most effective isolate due to its ability to partially deplete the predominant contaminants 9,10-anthracenedione and 7H-benz[DE]anthracen-7-one. A release of chloride ions was observed in soil treated with either Allescheriella sp. strain DABAC 1 or Stachybotrys sp. strain DABAC 3, suggesting the occurrence of oxidative dehalogenation. The autochthonous fungi led to a significant decrease in soil toxicity, as assessed by both the Lepidium sativum L. germination test and the Collembola mortality test.


Asunto(s)
Hongos/metabolismo , Hidrocarburos Aromáticos/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Antraquinonas/metabolismo , Biodegradación Ambiental , ADN de Hongos/análisis , ADN Espaciador Ribosómico/análisis , ADN Espaciador Ribosómico/genética , Hongos/clasificación , Hongos/crecimiento & desarrollo , Hongos/aislamiento & purificación , Lignina/metabolismo , Datos de Secuencia Molecular , Filogenia , Polímeros/metabolismo , ARN Ribosómico/genética , Análisis de Secuencia de ADN , Stachybotrys/metabolismo
12.
Chemosphere ; 60(10): 1393-400, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16054908

RESUMEN

The present study investigated the ability of the non-pathogenic fungus Fusarium lateritium to either degrade or modify aromatic substances in olive-mill dry residue (DOR) and to reduce its phytotoxicity. The 80% reduction of ethylacetate extractable phenols in DOR colonized by the fungus for 20 weeks appeared to be due to polymerization reactions of phenol molecules as suggested by mass-balance ultrafiltration and size-exclusion chromatography experiments. Several lignin-modifying oxidases, including laccase, Mn-peroxidase and Mn-inhibited peroxidase were detected in F. lateritium solid-state cultures. Tests performed with tomato seedlings in soils containing 6% (w/w) sterilized non-inoculated DOR showed that the waste was highly phytotoxic. By contract, F. lateritium growth on DOR for 20 weeks led to a complete removal of the waste toxicity and to a higher shoot dry weight of tomato plants than that obtained in the absence of DOR.


Asunto(s)
Fusarium/metabolismo , Olea , Solanum lycopersicum/crecimiento & desarrollo , Agricultura , Biodegradación Ambiental , Industria de Alimentos , Fusarium/enzimología , Fusarium/crecimiento & desarrollo , Residuos Industriales , Fenoles/análisis , Fenoles/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Brotes de la Planta/crecimiento & desarrollo , Ultrafiltración
13.
Chemosphere ; 54(7): 887-94, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14637346

RESUMEN

Olive-mill wastewater (OMW) exhibits highly phytotoxic properties, mainly due to phenols. A valuable option for OMW disposal is its agricultural use provided that phytotoxic effects are removed. The present investigation was aimed at evaluating the efficacy of the lignin-degrading fungus Lentinula edodes in achieving OMW detoxification. Germinability experiments on durum wheat showed that OMW phytotoxicity was significantly reduced by L. edodes cultures. Germinability on undiluted and twofold diluted OMW from fungal cultures was 34+/-5% and 57+/-6%, respectively, while on related incubation controls it was almost completely suppressed. These results suggest that fungal cultures of L. edodes would decrease the phytotoxicity of this waste.


Asunto(s)
Olea/química , Fenoles/toxicidad , Hongos Shiitake/metabolismo , Triticum/efectos de los fármacos , Contaminación Química del Agua/análisis , Análisis de Varianza , Cromatografía , Germinación/efectos de los fármacos , Residuos Industriales , Lacasa , Hongos Shiitake/química , Espectrofotometría , Triticum/fisiología
14.
Tech Coloproctol ; 8 Suppl 2: s295-9, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15666110

RESUMEN

Endoscopic polypectomy is the gold standard for the treatment of colorectal polyps. In the case of non-palpable lesions or to complete polyp removal, the lesions are located intra-operatively. With the advent of laparoscopy, identifying their position is even more important because there is no opportunity for intestinal palpation. Several methods of preoperative endoscopic marking have been proposed using different types of tattooing and recently using clips followed by ultrasonography detection. Innovative methods are analysed; magnetic endoscopic imaging is a reliable and accurate method for determining the anatomical position of the tip of the endoscope during colonoscopy. Radioguided colonic lesion identification needs a gamma detection probe. Endoscopic removal can be converted to endo-laparoscopic rendezvous, failing which, laparoscopic resection is a reliable and safe choice, offering all the advantages of minimally invasive surgical techniques.


Asunto(s)
Pólipos del Colon/diagnóstico , Pólipos del Colon/cirugía , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/cirugía , Laparoscopía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carbono , Colorantes , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Radiofármacos , Albúmina Sérica Radioyodada
15.
Chemosphere ; 50(8): 959-66, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12531700

RESUMEN

Olive-mill wastewater (OMW), an effluent of olive oil extraction process, is annually produced in huge amounts in olive growing areas. An interesting option for its disposal is the spreading on agricultural land, provided that phytotoxic effects are neutralized. The objective of the present investigation was to evaluate the potential of an enzyme-based treatment in removing OMW phytotoxicity. To this aim, germinability experiments on durum wheat (Triticum durum Desf. cv. Duilio) were conducted in the presence of different dilutions of raw or enzyme-treated OMW. OMW treatment with laccase resulted in a 65% and 86% reduction in total phenols and ortho-diphenols respectively, due their polymerization as revealed by size-exclusion chromatography. Raw OMW exerted a significant concentration-dependent inhibition on the germinability of durum wheat seeds which was evident up to a dilution rate of 1:8. When the effluent was treated with a fungal laccase, germinability was increased by 57% at a 1:8 dilution and by 94% at a 1:2 dilution, as compared to the same dilutions using untreated OMW. The treatment with laccase also decreased the mean germination time by about 1 day as compared to untreated controls. These results show that germinability inhibition due to OMW can be reduced effectively using fungal laccase, suggesting that phenols are the main determinants of its phytotoxicity.


Asunto(s)
Conservación de los Recursos Naturales , Fenoles/efectos adversos , Fenoles/metabolismo , Aceites de Plantas , Triticum/crecimiento & desarrollo , Eliminación de Residuos Líquidos/métodos , Fertilizantes , Industria de Alimentos , Hongos/enzimología , Germinación , Lacasa , Aceite de Oliva , Oxidorreductasas/farmacología , Semillas/crecimiento & desarrollo
16.
Org Lett ; 2(3): 401-2, 2000 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-10814333

RESUMEN

[reaction: see text] The effect of chiral substituents on the enamide nitrogen atom upon the diastereoselection of the Mn(III)-mediated 4-exo-trig cyclization to beta-lactams was studied. A significant level of diastereoselectivity was achieved when an amino acid ester moiety was included into the enamidic skeleton. The structure of the major diastereoisomer was suggested by semiempirical calculations.

17.
Bioorg Med Chem ; 8(2): 433-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10722166

RESUMEN

Three phenolic model compounds representing bonding patterns of residual kraft lignin were incubated with manganese peroxidase from Lentinula edodes. Extensive degradation of all the phenolic models, mainly occurring via side-chain benzylic oxidation, was observed. Among the tested model compounds the diphenylmethane alpha-5 phenolic model was found to be the most reactive, yielding several products showing oxidation and fragmentation at the bridging position. The non-phenolic 5-5' biphenyl and 5-5' diphenylmethane models were found unreactive.


Asunto(s)
Lentinula/enzimología , Lignina/química , Peroxidasas/química , Fenoles/química , Biodegradación Ambiental
18.
J Biotechnol ; 77(2-3): 265-73, 2000 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-10682285

RESUMEN

Immobilization of Lentinula edodes laccase on Eupergit C increased pH, thermal and proteolytic stability with slight modifications in laccase oxidation efficiency. Immobilized laccase proved to be efficiently stable in removing olive mill wastewater phenolics.


Asunto(s)
Enzimas Inmovilizadas , Óxido de Etileno , Residuos Industriales , Oxidorreductasas/metabolismo , Fenoles/aislamiento & purificación , Hongos Shiitake/enzimología , Agua/química , Estabilidad de Enzimas , Lacasa
19.
J Biotechnol ; 61(3): 209-18, 1998 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-9684339

RESUMEN

Biodegradation of olive-mill wastewater (OMW) was performed by the polyurethane-immobilized mycelium of Lentinula edodes. Throughout three consecutive treatment cycles of the effluent significant abatements of its polluting characteristics were observed. In fact, its contents in total organic carbon, total phenols, total ortho-diphenol were dramatically reduced. In addition, a significant effluent decolorization was evident.


Asunto(s)
Biodegradación Ambiental , Hongos/metabolismo , Contaminantes del Agua/metabolismo , Lacasa , Lignina/metabolismo , Región Mediterránea , Aceite de Oliva , Oxidorreductasas/metabolismo , Peróxidos/metabolismo , Fenoles/metabolismo , Aceites de Plantas , Administración de Residuos , Residuos
20.
Minerva Chir ; 52(3): 283-7, 1997 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-9148219

RESUMEN

Carcinoid tumors are among the most frequently neuroendocrine neoplasms of the gastrointestinal tract. They occur more commonly as benign diseases but malignant ones can also be found. The peak age incidence varies with the location of the tumor, with appendiceal tumors being diagnosed at an overage of 36 years, whereas non appendiceal tumors are found typically in the fifth sixth decades of life. There is no sex predilection of the tumors. Most carcinoid tumors are found within the appendix (40-50%) or small intestine (25%). Less common sites include the rectum (15%), main bronchus (10%), duodenum (3-8%) and stomach (2%). Most carcinoid tumors are found incidentally at operation and cause no symptoms. If symptoms do occur, they can be either non specific include intermittent crampy abdominal pain, vomiting and distension caused by intestinal obstruction. The prognosis depends on the site of the tumor and its size. Most carcinoid tumors (75%) are less than 1 cm in size and only 5% are greater than 2 cm. The incidence of metastatic disease is related directly to the size of the tumor at all locations. Carcinoid tumor with size less than 1 cm give linfonodal metastasis only in 3-5%; the other with size over 2 cm give metastasis in the 70-75% of the cases. The 5-years survival for all carcinoid tumors are approximately 85%. Five years rate is higher (> 80%) in carcinoid tumors of appendix and rectum than in gastroduodenal, ileal and colonic neoplasm (< 60%). In this paper the authors report a case of malignant carcinoid of the duodenum.


Asunto(s)
Tumor Carcinoide , Neoplasias Duodenales , Tumor Carcinoide/diagnóstico , Tumor Carcinoide/cirugía , Diagnóstico Diferencial , Neoplasias Duodenales/diagnóstico , Neoplasias Duodenales/cirugía , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad
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