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1.
Surg Endosc ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955837

RESUMO

AIMS: To evaluate the safety profile of robotic cholecystectomy performed within the United Kingdom (UK) Robotic Hepatopancreatobiliary (HPB) training programme. METHODS: A retrospective evaluation of prospectively collected data from eleven centres participating in the UK Robotic HPB training programme was conducted. All adult patients undergoing robotic cholecystectomy for symptomatic gallstone disease or gallbladder polyp were considered. Bile duct injury, conversion to open procedure, conversion to subtotal cholecystectomy, length of hospital stay, 30-day re-admission, and post-operative complications were the evaluated outcome parameters. RESULTS: A total of 600 patients were included. The median age was 53 (IQR 65-41) years and the majority (72.7%; 436/600) were female. The main indications for robotic cholecystectomy were biliary colic (55.5%, 333/600), cholecystitis (18.8%, 113/600), gallbladder polyps (7.7%, 46/600), and pancreatitis (6.2%, 37/600). The median length of stay was 0 (IQR 0-1) days. Of the included patients, 88.5% (531/600) were discharged on the day of procedure with 30-day re-admission rate of 5.5% (33/600). There were no bile duct injuries and the rate of conversion to open was 0.8% (5/600) with subtotal cholecystectomy rate of 0.8% (5/600). CONCLUSION: The current study confirms that robotic cholecystectomy can be safely implemented to routine practice with a low risk of bile duct injury, low bile leak rate, low conversion to open surgery, and low need for subtotal cholecystectomy.

2.
Pediatr Transplant ; 26(1): e14139, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34545678

RESUMO

BACKGROUND: Pediatric liver transplant (PLT) activity has flourished over time although with limited expansion in the graft pool. The study aims to identify pre-transplant factors that predict post-transplant patient and graft survival in the PLT population. METHODS: Retrospective review of PLTs at a single tertiary transplant unit from 2000 to 2019. Univariate and multivariate analyses of pre-transplant factors were performed to identify predictors of patient and graft survival. RESULTS: Two hundred and seventy-six patients received 320 PLTs. The most common cause of graft loss was hepatic artery thrombosis (n = 13, 29.6%). The most common cause of mortality was sepsis (n = 11, 29.7%). Univariate analysis showed that the following variables had a significant (p < .05) impact on patient survival: recipient age, weight, height, graft type (technical variant graft), transplant category (acute liver failure), the era of transplant, and invasive ventilation. The following variables had a significant (p < .05) impact on graft survival: recipient age, weight, height, transplant category (acute liver failure), and the era of transplant. Multivariate analysis precluded the era of transplant as the only significant factor for patient survival; patients transplanted after 2005 had significantly higher patient survival. No independent factor predicting graft survival was identified. For children transplanted after 2005, the only factor that predicted patient survival was pre-transplant invasive ventilation. CONCLUSIONS: Our study suggests that the learning curve and pre-transplant invasive ventilation in the recipient have a significant impact on patient survival. The traditional view of worse outcomes of smaller PLT candidates should be changed.


Assuntos
Doença Hepática Terminal/mortalidade , Doença Hepática Terminal/cirurgia , Sobrevivência de Enxerto , Transplante de Fígado/mortalidade , Complicações Pós-Operatórias/mortalidade , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Análise Multivariada , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento
3.
Nephrol Dial Transplant ; 34(10): 1788-1798, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29955846

RESUMO

BACKGROUND: This study compared long-term outcomes of renal transplantation from donors following donation after circulatory death (DCD) with those following donation after brain death (DBD) from one of the largest centres in the UK. METHOD: Recipients of renal transplants from deceased donors between 2002 and 2014 were identified from a prospectively maintained database. Outcomes were compared between DCD (468) and DBD (905) donors and between standard criteria donors (SCDs) and extended criteria donors (ECDs). RESULTS: Graft survival (GS) and patient survival (PS) from DCD and DBD donors were comparable up to 10 years (GS: 61 versus 55%, P = 0.780; PS: 78 versus 71%, P = 0.285, respectively). Graft function was comparable after 3 months. GS and function were worse in the ECD groups, with no difference between EC-DBD and EC-DCD. PS in the ECD groups was worse than the SCD groups and PS in the EC-DCD group was worse than in the EC-DBD group. DCD donors were an independent risk factor for delayed graft function. Post-operative complications and EC-DCD donation were independent risk factors for reduced GS and PS. CONCLUSION: This study supports the use of DCD renal grafts with comparable long-term survival and function to DBD grafts. The use of EC-DCD grafts is justified in selected recipients and provides acceptable function and survival advantages over dialysis.


Assuntos
Função Retardada do Enxerto/mortalidade , Sobrevivência de Enxerto , Transplante de Rim/mortalidade , Complicações Pós-Operatórias , Doadores de Tecidos/provisão & distribuição , Coleta de Tecidos e Órgãos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Morte , Função Retardada do Enxerto/etiologia , Circulação Extracorpórea , Feminino , Humanos , Lactente , Recém-Nascido , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
4.
J Environ Manage ; 245: 358-366, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31158688

RESUMO

Contamination of agricultural land(s) is a major problem worldwide which is associated with activities of petroleum industry. Due to these exploration activities remedial techniques for clean-up of contaminated agricultural soil(s) has become an alarming research topic. Hydrocarbon utilizing bacterial consortium (HUBC), isolated from petroleum crude (petroleum industry waste water and soil) contaminated sites, India has been used for soil microcosm study. The aim of present study was to compare potency of five different techniques to remediate petroleum hydrocarbons contaminated agricultural soil by employing soil microcosm study. To the best of our knowledge this is the first report for comparison of five different techniques (abiotic control, natural attenuation, biostimulation, bioaugmentation and simultaneous bioaugmentation & biostimulation) for bioremediation of agricultural soil using consortium of hydrocarbon utilizers by employing soil microcosms. Concurrent application of bioaugmentation (with HUBC) and biostimulation (with nutrient amendments) in the soil microcosm resulted in 93.67 ±â€¯1.80% hydrocarbons degradation in 45 days of experiment and hydrocarbon utilizing bacterial count was recorded 4.11 ±â€¯0.11 × 108 CFU/g. In the bioaugmented and biostimulated soil microcosm organic carbon was reduced from 3.49 ±â€¯0.08% to 0.62 ±â€¯0.11% with simultaneous decrease of other nutrients. The consortium could survive in artificially crude oil contaminated and nutrients amended agricultural soil microcosm and could degrade petroleum hydrocarbons effectively in soil microcosm conditions. This suggests its application as a potential bioremediation agent for farmland restoration i.e. management of soil environment.


Assuntos
Petróleo , Poluentes do Solo , Biodegradação Ambiental , Suplementos Nutricionais , Hidrocarbonetos , Índia , Nutrientes , Solo , Microbiologia do Solo
5.
Indian J Microbiol ; 59(3): 356-364, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31388214

RESUMO

The aim of work was to check and make comparison of efficacy for five approaches for petroleum crude contaminated agricultural soil remediation by making use of soil microcosms. Concerning the published literature in our information, this is the first report comparing five approaches i.e. abiotic losses, native microbial flora, nutrient amendments and pre-adapted native microbial culture and concurrent amendments of nutrients + pre-adapted native microbial culture for agricultural soil bioremediation using Pseudomonas aeruginosa NCIM 5514 by performing soil microcosm experiments. 96.00 ± 0.18% degradation of petroleum hydrocarbon fractions in 60 days of the experiment was observed when nutrients and P. aeruginosa NCIM 5514 were applied concomitantly. In nutrients- and P. aeruginosa NCIM 5514-added microcosm reduction in nitrogen, organic carbon, and phosphorus was noted. P. aeruginosa NCIM 5514, can be applied as a prospective bioremediation agent to remediate petroleum crude contaminated soil.

6.
World J Transplant ; 13(3): 96-106, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36968135

RESUMO

BACKGROUND: Children with acute liver failure (ALF) who meet the criteria are eligible for super-urgent transplantation, whereas children with end-stage chronic liver disease (ESCLD) are usually transplanted electively. Pediatric liver trans plantation (PLT) in ALF and ESCLD settings has been well described in the literature, but there are no studies comparing the outcomes in these two groups. AIM: To determine if there is a difference in post-operative complications and survival outcomes between ALF and ESCLD in PLT. METHODS: This was a retrospective observational study of all primary PLTs performed at a single center between 2000 and 2019. ALF and ESCLD groups were compared for pretransplant recipient, donor and operative parameters, and post-operative outcomes including graft and patient survival. RESULTS: Over a 20-year study period, 232 primary PLTs were performed at our center; 195 were transplanted for ESCLD and 37 were transplanted for ALF. The ALF recipients were significantly older (median 8 years vs 5.4 years; P = 0.031) and heavier (31 kg vs 21 kg; P = 0.011). Living donor grafts were used more in the ESCLD group (34 vs 0; P = 0.006). There was no difference between the two groups concerning vascular complications and rejection, but there were more bile leaks in the ESCLD group. Post-transplant patient survival was significantly higher in the ESCLD group: 1-, 5-, and 10-year survival rates were 97.9%, 93.9%, and 89.4%, respectively, compared to 78.3%, 78.3%, and 78.3% in the ALF group (P = 0.007). However, there was no difference in 1-, 5-, and 10-year graft survival between the ESCLD and ALF groups (90.7%, 82.9%, 77.3% vs 75.6%, 72.4%, and 66.9%; P = 0.119). CONCLUSION: Patient survival is inferior in ALF compared to ESCLD recipients; the main reason is death in the 1st year post-PLT in ALF group. Once the ALF children overcome the 1st year after transplant, their survival stabilizes, and they have good long-term outcomes.

7.
Bioresour Technol ; 319: 124240, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33254463

RESUMO

This study was aimed at remediation ofoily waste contaminated area by utilizing a newly obtained bacterium. For experimental setup three different approachessuch as bioaugmentation, natural attenuation and abiotic factors were employed. In bioaugmented experimental set up (treatment withP. aeruginosaNCIM 5514),76.14 ± 0.85% loss in oily waste with notable hydrocarbon utilizers was noted in 56 days. From the results, it was concluded that bioaugmentation with novel P. aeruginosasp. (oily waste degrader) could remediate oily waste pollution effectively. Results of this study demonstrate applicability of P. aeruginosa NCIM 5514 for environmental sustainability.


Assuntos
Petróleo , Poluentes do Solo , Biodegradação Ambiental , Poluição Ambiental , Hidrocarbonetos , Pseudomonas aeruginosa , Microbiologia do Solo
8.
Sci Total Environ ; 763: 142934, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33268247

RESUMO

Petroleum sludge has been reported as noteworthy hazardous solid waste generated from industrial activities of petroleum sector. Environment friendly and economically sound treatment of petroleum sludge has attracted global attention worldwide and has become a thrust area of research. Petroleum sludge bioremediation is gaining interest of researchers globally to clean pollutants from soil ecosystems. To date of submission of the work there is no literature available reporting comparing five approaches for remediation of agricultural soil polluted with petroleum sludge employing hydrocarbon utilizing bacterial consortium (HUBC). Further studies on toxicity were performed through pot experiments using Vigna radiata. The aim of this research work was to compare capability of five approaches for remediating petroleum sludge polluted agricultural soil by employing soil microcosms. Best results were obtained when simultaneous application of HUBC and nutrients was performed in microcosm. Highest decrease (93.14 ± 1.75%) of petroleum sludge with sufficient count of hydrocarbon utilizers and decreased nutrients in 42 days was reported. Quality improvement of petroleum sludge contaminated agricultural soil after its bioremediation was performed by pot experiments by checking germination of V. radiata seeds. 85.71% germination of seeds in 5 days was noted for treated soil. Thus, HUBC can be applied as a bioremediating consortium to reclaim petroleum sludge polluted soil.


Assuntos
Petróleo , Poluentes do Solo , Biodegradação Ambiental , Ecossistema , Hidrocarbonetos , Nutrientes , Esgotos , Solo , Microbiologia do Solo , Poluentes do Solo/análise
9.
Sci Total Environ ; 745: 141043, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32717605

RESUMO

Oily sludge is a hazardous waste generated through petroleum producing and processing industrial units. Due to its harmful environmental impacts, it needs to be treated in sustainable manner. The present study aimed to evaluate influence of bioaugmentation on oily sludge biodegradation efficiency of a novel hydrocarbon utilizing bacterial consortium (HUBC) using microcosms. Three approaches (bioaugmentation, natural attenuation and abiotic factors) were used for microcosm studies. Bioaugmentation treatment showed best results for oily sludge degradation than natural attenuation and abiotic factors, resulting 82.13 ± 1.21% oily sludge degradation in 56 days. In bioaugmented microcosm on 56th day 0.30 ± 0.07 × 108 CFU/g hydrocarbon utilizing bacteria were noted. Results showed that HUBC could be used to remediate soil polluted with oily sludge. This study imparts a notable approach for farming application(s).


Assuntos
Petróleo , Poluentes do Solo/análise , Bactérias , Biodegradação Ambiental , Hidrocarbonetos , Campos de Petróleo e Gás , Microbiologia do Solo
10.
Sci Total Environ ; 737: 139766, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32526573

RESUMO

Agricultural land pollution is key a problem globally, which is linked with growth of industries. Petroleum industrial sector is one of the major industrial sectors and the activities of petroleum industry lead to the agricultural land pollution. Oily sludge is a type of solid and hazardous waste generated from petroleum industrial activities. Hence, there is an urgent need to find remediation methods of the oily sludge contaminated agricultural land. Thus, the aim of this work was to study bioremediation of oily sludge polluted soil employing a novel strain of Pseudomonas aeruginosa and evaluation of phytotoxicity on germination of Vigna radiata seed in pots. Five different approaches were adopted for the bioremediation studies, which included Bioaugmentation + Biostimulation, bioaugmentation, biostimulation, natural attenuation and abiotic factors. Simultaneous application of P. aeruginosa NCIM 5514 and nutrients in microcosm showed 92.97 ± 0.92% decrease in oily sludge with good hydrocarbon utilizing bacterial count and decreased nutrient level in 56 days. Pot experiments on seed germination of mung beans (Vigna radiata) seeds was performed by pot experiments. 80.95% germination in five days in treated soil. From the results it was concluded that simultaneous use of oily sludge degraders and nutrient supplement could revive seed germination ability of oily sludge polluted soil effectively. This is first report of comparing five techniques to bioremediate oily sludge polluted soil using Pseudomonas aeruginosa, followed by pot study using V. radiata seeds, showing that P. aeruginosa can be an efficient bioremediation agent and can be effectively used for remediation of oily sludge contaminated soil.


Assuntos
Petróleo/análise , Poluentes do Solo/análise , Biodegradação Ambiental , Germinação , Hidrocarbonetos , Pseudomonas aeruginosa , Sementes/química , Esgotos , Solo , Microbiologia do Solo
11.
Bioresour Technol ; 288: 121577, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31174086

RESUMO

This work was aimed to evaluate six qualitative and quantitative methods (hemolytic activity, cetyltrimethylammonium bromide agar plate method, oil spread method, drop collapse method, surface tension measurement and emulsification index) to study biosurfactant production by sixty-nine bacterial isolates which were obtained from petroleum crude contaminated soil and water samples. Among all isolates, Pseudomonas aeruginosa NCIM 5514 was evaluated as the most potent isolate producing rhamnolipid. Effectiveness of growth medium pH, inoculum size and concentration of NaCl on surface active properties and biomass & rhamnolipid production in fermentation medium were studied. Highest surface activity was obtained at 1% (v/v) inoculum at initial pH of the medium 7.2, which resulted 4.389 ±â€¯0.019 and 3.146 ±â€¯0.087 g/l biomass and rhamnolipid, respectively. Notable surface activity of rhamnolipid produced by P. aeruginosa NCIM 5514 makes it feasible to be used for industrial application.


Assuntos
Pseudomonas aeruginosa , Tensoativos , Glicolipídeos , Tensão Superficial
12.
Transplantation ; 103(4): e79-e88, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30418426

RESUMO

BACKGROUND: No data exist to evaluate how hepatectomy time (HT), in the context of donation after cardiac death (DCD) procurement, impacts short- and long-term outcomes after liver transplantation (LT). In this study, we analyze the impact of the time from aortic perfusion to end of hepatectomy on outcomes after DCD LT in the United Kingdom. METHODS: An analysis of 1112 DCD donor LT across all UK transplant centers between 2001 and 2015 was performed, using data from the UK Transplant Registry. Donors were all Maastricht Category III. Graft survival after transplantation was estimated using Kaplan-Meier method and logistic regression to identify risk factors for primary nonfunction (PNF) and short- and long-term graft survivals after LT. RESULTS: Incidence of PNF was 4% (40) and in multivariate analysis only cold ischemia time (CIT) longer than 8 hours (hazard ratio [HR], 2.186; 95% confidence interval [CI], 1.113-4.294; P = 0.023) and HT > 60 minutes (HR, 3.669; 95% CI, 1.363-9.873; P = 0.01) were correlated with PNF. Overall 90-day, 1-, 3-, and 5-year graft survivals in DCD LT were 91.2%, 86.5%, 80.9%, and 77.7% (compared with a donation after brain death cohort in the same period [n = 7221] 94%, 91%, 86.6%, and 82.6%, respectively [P < 0.001]). In multivariate analysis, the factors associated with graft survival were HT longer than 60 minutes, donor older than 45 years, CIT longer than 8 hours, and recipient previous abdominal surgery. CONCLUSIONS: There is a negative impact of prolonged HT on outcomes on DCD LT and although HT is 60 minutes or longer is not a contraindication for utilization, it should be part of a multifactorial assessment with established prognostic donor factors, such as age (>45 y) and CIT (>8 h) for an appropriately selected recipient.


Assuntos
Hepatectomia , Transplante de Fígado , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Adulto , Isquemia Fria , Feminino , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
13.
ANZ J Surg ; 88(5): 415-420, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29752783

RESUMO

BACKGROUND: This meta-analysis aimed to compare living donor liver transplantation (LDLT) grafts with a graft-to-recipient weight ratio (GRWR) of <0.8 to grafts with a GRWR ≥0.8 with regards to small-for-size syndrome (SFSS) and short and longer term outcomes. METHODS: An electronic search was performed of the MEDLINE, EMBASE and PubMed databases until December 2016 using both subject headings (MeSH) and free text. Pooled odds ratios and hazard ratios were calculated using fixed- and random-effects models for meta-analysis. RESULTS: Eight studies including 1833 patients met the inclusion criteria. The rate of SFSS was 10% in the <0.8 group and 5% in the ≥0.8 group (odds ratio: 1.69 (1.09, 2.61) (P = 0.020)). No significant difference was noted between the two groups with regards to graft survival up to 5 years (hazard ratio: 1.31 (0.88, 1.94) (P = 0.190)). Similarly, no significant difference was noted in overall complications (P = 0.06), biliary (P = 0.290) or vascular complications (P = 0.190), perioperative haemorrhage (P = 0.150), post-operative mortality (P = 0.810) and rejection (P = 0.160). CONCLUSION: The incidence of SFSS in grafts with a GRWR <0.8 is more than in GRWR ≥0.8; however, the low GRWR does not appear to impact perioperative outcomes or graft survival.


Assuntos
Transplante de Fígado/efeitos adversos , Doadores Vivos , Tamanho do Órgão , Complicações Pós-Operatórias/etiologia , Humanos , Síndrome
14.
Bioresour Technol ; 232: 389-397, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28238638

RESUMO

Surfactants are one of the most versatile group of chemicals used in various industrial processes. Their market is competitive, and manufacturers will have to expand surfactant production in ecofriendly and cost effective manner. Increasing interest in biosurfactants led to an intense research for environment friendly and cost-efficient production of biosurfactant. Structural diversity and functional properties of biosurfactants make them an attractive group of compounds for potential use in wide variety of industrial, environmental and biotechnological applications. Screening methods make task easier to obtain potential biosurfactant producing microorganisms. Variety of purification and analytical methods are available for biosurfactant structural characterization. This review aims to compile information on types and properties of biosurfactant, microbial screening methods as well as biosynthesis, extraction, purification and structural characterization of biosurfactant using rhamnolipid as a model biosurfactant. It also describes factors affecting rhamnolipid production. It gives an overview of oil recovery using biosurfactant from Pseudomonas aeruginosa.


Assuntos
Glicolipídeos/análise , Glicolipídeos/isolamento & purificação , Tensoativos/análise , Tensoativos/isolamento & purificação , Bactérias/metabolismo , Biotecnologia , Glicolipídeos/biossíntese , Óleos/isolamento & purificação
15.
J Gastrointest Surg ; 21(2): 266-274, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27770289

RESUMO

INTRODUCTION: This study analysed the effect of age on survival in patients undergoing major hepatectomy (MH) for colorectal liver metastases (CRLM). The effect of adjuvant chemotherapy (AC) with age was also assessed. METHOD: Patients undergoing MH for CRLM between 1996 and 2011 were reviewed. Patients aged <75 or ≥75 were compared for disease-free (DFS) and overall survival (OS) as well as impact of AC on survival. RESULTS: Seven hundred twenty-seven patients underwent MH of which 105 (14 %) were aged ≥75. Morbidity was greater in the ≥75 group (25 versus 34 %, p = 0.048). No difference was noted in mortality. There was no difference in DFS between the two groups at 5 years (16.8 vs 18.9 months (p = 0.570). OS was longer in the <75 group (38.6 vs 32.0 months (p = 0.001). DFS was better in groups receiving AC than those not (<75 24.2 vs 12.2 months (p = <0.001) and ≥75 24 vs 12.1 months (p = 0.007)). OS in the ≥75 group was improved in the group receiving AC compared to the ≥75 group not (41.1 vs 16.6 months, p = 0.005). Age ≥75 was not an independent risk factor for reduced DFS on multivariate analysis. CONCLUSION: Well-selected patients aged ≥75 should be considered for MH followed by adjuvant chemotherapy.


Assuntos
Neoplasias Colorretais/cirurgia , Hepatectomia/mortalidade , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/etiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Quimioterapia Adjuvante/efeitos adversos , Neoplasias Colorretais/patologia , Feminino , Hepatectomia/efeitos adversos , Humanos , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Análise de Sobrevida
16.
Bioresour Technol ; 221: 510-516, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27677153

RESUMO

The present research work was undertaken with a mandate to study carbon spectrum utilization and structural characterization of biosurfactant produced by indigenous Pseudomonas aeruginosa NCIM 5514, which showed unique properties to utilize a large number of carbon sources effectively for production of biosurfactant, although glucose was the best carbon substrate. In Bushnell-Hass medium supplemented with glucose (1%, w/v), 3.178±0.071g/l biosurfactant was produced by this isolate in 96h. The biosurfactant produced showed surface tension and emulsification activity values from 29.14±0.05 to 62.29±0.13mN/m and 88.50±1.96 to 15.40±0.91%, respectively. Toluene showed highest emulsification activity followed by kerosene. However, kerosene exhibited emulsion stability for 30days. Biosurfactant was characterized as a mixture of di-rhamnolipid (Rha-Rha-C10-C14:1) and mono-rhamnolipid (Rha-C8-C10) by FTIR, ESI-MS and LC-MS techniques. High biosurfactant yield opens up doors for the isolate to find utility in various industries.


Assuntos
Carbono/metabolismo , Pseudomonas aeruginosa/metabolismo , Tensoativos/química , Tensoativos/metabolismo , Proliferação de Células , Espectrometria de Massas , Estrutura Molecular , Relação Estrutura-Atividade , Tensão Superficial
17.
Bioresour Technol ; 222: 195-201, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27718402

RESUMO

The aim of this work was to study the potential of an indigenous strain of Pseudomonas aeruginosa NCIM 5514, isolated from petroleum-polluted soil, for the biodegradation of crude petroleum oil. The isolate completely decolorized 2,6-dichlorophenol indophenol in 120h when grown at (37±1°C), indicating its hydrocarbon utilizing nature. Ex situ biodegradation study was performed to find out quantitative utilization and biodegradation of paraffin(s) present in crude oil. When the culture was grown in Bushnell-Hass medium containing crude oil (3%,v/v) at 37°C, 180rpm for 60days, the viscosity of the oil was reduced from 1883cp to 1002cp. Gravimetric and gas chromatographic analysis showed 61.03% and 60.63% of biodegradation of C8-C36+ hydrocarbons, respectively. These results indicated that the isolate has potential to be used for ex-situ and in-situ bioremediation of hydrocarbon pollutants and could have promising applications in petrochemical industry.


Assuntos
Biodegradação Ambiental , Petróleo/microbiologia , Pseudomonas aeruginosa/metabolismo , Poluentes do Solo/metabolismo , Hidrocarbonetos/metabolismo , Petróleo/análise
18.
Bioresour Technol ; 220: 175-182, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27567478

RESUMO

The aim of this work was to study the Microbial Enhanced Oil Recovery (MEOR) employing core field model ex-situ bioaugmenting a thermo- and halo-tolerant rhamnolipid produced by Pseudomonas aeruginosa. Thin Layer Chromatography (TLC) revealed that the biosurfactant produced was rhamnolipid type. Nuclear Magnetic Resonance analysis showed that the purified rhamnolipids comprised two principal rhamnolipid homologues, i.e., Rha-Rha-C10-C14:1 and Rha-C8-C10. The rhamnolipid was stable under wide range of temperature (4°C, 30-100°C), pH (2.0-10.0) and NaCl concentration (0-18%, w/v). Core Flood model was designed for oil recovery operations using rhamnolipid. The oil recovery enhancement over Residual Oil Saturation was 8.82% through ex-situ bioaugmentation with rhamnolipid. The thermal stability of rhamnolipid shows promising scope for its application at conditions where high temperatures prevail in oil recovery processes, whereas its halo-tolerant nature increases its application in marine environment.


Assuntos
Glicolipídeos/biossíntese , Poluição por Petróleo , Pseudomonas aeruginosa , Cromatografia em Camada Fina , Glicolipídeos/síntese química
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