در هنگام جستجو کلمه در قسمت عنوان میتوانید کلمات مورد جستجو را با کاراکتر (-) جدا کنید.
کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Taguchi,Plackett-Burman,Biodegradation Optimization,Marinobacter litoralis
- چکیده:
- چکیده انگلیسی: Background: Hydrocarbons degradation is principally achieved by microorganisms in natural environments. The extent of hydrocarbons biodegradation is mainly conditioned by environmental factors and its success depends on the optimal condition for the crude oil degrading isolates. Objectives: The aims of the current study was to isolate and identify crude oil degrading bacterium from surface sediments of Qeshm Island, Iran and to evaluate the efficiency of statistically-based experimental design for the optimization of crude oil degradation performed by the isolated strain. Materials and Methods: Crude oil degrading bacteria were isolated by serial dilutions of bacterial consortium. In order to optimize crude oil biodegradation by isolated strain, Plackett-Burman experimental design was used to evaluate nine factors affecting crude oil biodegradation in twelve experimental trials. To observe the best yield in crude oil biodegradation, factor which had higher effects were considered for the next stage in the biodegradation optimization process using the Taguchi experimental design. Results: A gram-negative bacterium strain signed as KK1- strain (with 98% homology with Marinobacter litoralis) was isolated from enrichment consortium. Among the various variables screened using Plackett-Burman experimental design, pH, temperature, salinity and NH4Cl were determined as the most significant factors and considered for the next stage in the biodegradation optimization process using the Taguchi experimental design. Theoretically, the optimum degradation conditions were determined as: pH = 8, temperature = 35˚C, salinity = 30 ppt and NH4Cl = 1 g.L-1. The validity of the predicted optimized condition was tested by conducting experiment considering the predicted criteria. Biodegradation efficiency of 58.32±5.57% was achieved under suggested condition which was significantly higher than the primary condition (35%). Conclusions: Indigenous bacteria from surface sediments of Qeshm Island were found to be able to degrade crude oil. Our results showed that a combination of the Plackett-Burman and the Taguchi experimental design may be successfully used to find the optimal amounts of those factors for crude oil biodegradation.
- انتشار مقاله: 20-07-1392
- نویسندگان: Mohsen Shahriari Moghadam,Gholamhossein Ebrahimipour,Behrooz Abtahi,Nafsa Khazaei,Negin Karbasi
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Environmental Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: optimization,Biodegradation,Malathion,Serratia marcescens,Pesticide
- چکیده:
- چکیده انگلیسی: The global use of pesticides has resulted in the contamination of various ecosystems worldwide. The impact of these pesticides can be reduced through bioremediation. The factors that influence the biodegradation rate include the isolation of efficient bacteria for use in remediation and the determination of optimal biodegradation conditions. In this study, malathion degrading bacteria were isolated from agricultural soil samples taken from the Arvandkenar region in Iran. To optimize the biodegradation of malathion by an isolated strain, the effect of four parameters (temperature, salinity, NH4Cl and K2HPO4) was evaluated while considering protein concentrations at different times. The malathion remaining in the media was measured using the gas chromatography method. A gram-negative bacterium strain BNA1 with malathion biodegrading ability was isolated from the soil sample which showed a 99% similarity to Serratia marcescens. The optimum biodegradation condition occurred at a temperature = 30 ˚C, salinity = 0 %, NH4Cl = 0.25 g/L and K2HPO4 = 0.25 g/L. A biodegradation efficiency of 65% was obtained under the above-mentioned condition. The results of this study revealed the significant capability of BNA1 in the biodegradation of malathion. Therefore, the use of an isolated strain may be considered as an important tool in the bioremediation of pesticide-contaminated soil.
- انتشار مقاله: 29-03-1395
- نویسندگان: Banafshe Nadalian,Mohsen Shahriari Moghadam,Gholamhossein Ebrahimipour
- مشاهده