نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه میکروبیولوژی ، علوم پزشکی تهران،دانشگاه آزاد اسلامی، تهران،ایران

2 هیات علمی/ پژوهشکده مواد و سوخت هسته‌ای، پژوهشگاه علوم و فنون هسته‌ای، تهران، ایران

3 دانشکده زیست شناسی، پردیس علوم، دانشگاه تهران، تهران، ایران

چکیده

معدنی‌‌سازی زیستی سلنیم توسط باکتری‌ها نه ‌تنها پتانسیل لازم برای زدودن اکسی آنیون‌های سمی سلنیم را از محیط دارا می باشد، بلکه می‌تواند سلنیم عنصری را در مقیاس نانو تولید نماید. در این پژوهش از روش رویه پاسخ با طراحی باکس- بنکن برای ارزیابی و بهینه سازی تأثیر پارامترهای عملیاتی مختلف بر فرآیند احیای زیستی سلنات مورد استفاده گردید. مدل درجه دوم پیشنهادی با ضریب همبستگی 96/0R2= ضمن پیش‌بینی مناسب رفتار فرآیند، مقدار 25/41درصد احیای سلنات توسط باکتری Bacillus sp. Strain TR-6 را در شرایط 24/5 درصد تلقیح اولیه باکتری، مدت زمان 24 ساعت و مقدار mM 8/3 نمک سلنات سدیم به عنوان نقطه بهینه تعیین نمود. مطالعات میکروسکوپ الکترونی نگاره مجهز به سیستم طیف سنجی پراش انرژی پرتو ایکس توانایی تولید نانوسفرهای سلنیم توسط باکتری منتخب را تاٴیید کرد. نهایتاً باکتری مذکور به عنوان یک باکتری منتخب باارزشی در فناوری های نانو و معدنی‌‌سازی زیستی سلنیم معرفی می گردد.

کلیدواژه‌ها

عنوان مقاله [English]

Application of Response Surface Methodology in optimization of Selenate bioreduction to selenium nanoparticles by Bacillus sp. Strain TR-6

نویسندگان [English]

  • Atieh Sadat Razavi 1
  • Parisa Tajer Mohammad Ghazvini 2
  • javad hamedi 3

1 Department of Microbiology,Tehran Medical Sciences,Islamic Azad University,Tehran,Iran

2 Materials and Nuclear Fuel Research School, Nuclear Science and Technology Research Institute, Tehran, Iran

3 Department of Biology, Faculty of Science, University of Tehran, Tehran, Iran

چکیده [English]

Biomineralization of selenium by bacteria not only has the potential to remove toxic selenium oxyanions from the environment, but can also produce nano- scale elemental selenium. In this work, the response surface method (RSM) based on the Box- Behnken design was used for evaluation and optimization of the different process parameters effect on the bioreduction process of selenate. The proposed second order model with a correlation coefficient R2 = 0.96 appropriately predicted the process behavior and determined the 41.25 percent reduction of selenate by Bacillus sp. Strain TR-6 at 5.24 percent initial bacterial inoculation, process time of 24 h and 3.8 mM concentration of sodium selenate as the optimum condition. Scanning electron microscope (SEM) with the Energy Dispersive X-ray spectroscopy (EDX) confirmed the ability of the selected bacteria to produce selenium nanospheres. Finally, Bacillus sp. Strain TR-6 is determined as a valuable candidate for nano- technologies and selenium biomineralization processes.

کلیدواژه‌ها [English]

  • Bacterial Reduction
  • Selenium Oxyanions
  • Experimental Design
  • Nanobiotechnology
Butler, C.S., Debieux, C.M., Dridge, E.J., Splatt, P., Wright, M. 2012. Biomineralization of selenium by the selenate-respiring bacterium Thauera selenatis, Biochemical Society Transactions, 40(6), 1239-1243.
Dobias, J., Suvorova, E.I., Bernier-Latmani, R. 2011. Role of proteins in controlling selenium nanoparticle size. Nanotechnology, 22(19), 195605.
Eswayah, A.S., Smith, T.J., Gardiner, P.H. 2016. Microbial transformations of selenium species of relevance to bioremediation. Appl. Environ. Microbiol., 82(16), 4848-4859.
Nancharaiah, Y.V., Lens, P.N. 2015a. Selenium biomineralization for biotechnological applications. Trends in biotechnology, 33(6), 323-330.
Nancharaiah, Y.V., Lens, P.N.L. 2015b. Ecology and Biotechnology of Selenium-Respiring Bacteria. Microbiology and Molecular Biology Reviews, 79(1), 61-80.
Oremland, R.S., Herbel, M.J., Blum, J.S., Langley, S., Beveridge, T.J., Ajayan, P.M., Sutto, T., Ellis, A.V., Curran, S. 2004. Structural and spectral features of selenium nanospheres produced by Se-respiring bacteria. Applied and environmental microbiology, 70(1), 52-60.
Oremland, R.S., Hollibaugh, J.T., Maest, A.S., Presser, T.S., Miller, L.G., Culbertson, C.W. 1989. Selenate reduction to elemental selenium by anaerobic bacteria in sediments and culture: biogeochemical significance of a novel, sulfate-independent respiration. Appl. Environ. Microbiol., 55(9), 2333-2343.
Piroeva, I., Atanassova-Vladimirova, S., Dimowa, L., Sbirkova, H., Radoslavov, G., Hristov, P., Shivachev, B. 2013. A simple and rapid scanning electron microscope preparative technique for observation of biological samples: application on bacteria and DNA samples. Bulg. Chem. Commun, 45(4), 510-515.
Preetha, B., Viruthagiri, T. 2007. Application of response surface methodology for the biosorption of copper using Rhizopus arrhizus. Journal of hazardous materials, 143(1-2), 506-510.
Raevskaya, A.E., Stroyuk, A.L., Kuchmiy, S.Y., Dzhagan, V.M., Zahn, D.R., Schulze, S. 2008. Annealing-induced structural transformation of gelatin-capped Se nanoparticles. Solid State Communications, 145(5-6), 288-292.
Razavi, A.S. 2019. Study of Biomineralization of Selenium by the Seleno-oxyanions Reducing Microorganisms, Master of Science Thesis, Islamic Azad University, Tehran Medical Sciences Branch.
Santos, S., Ungureanu, G., Boaventura, R., Botelho, C. 2015. Selenium contaminated waters: an overview of analytical methods, treatment options and recent advances in sorption methods. Science of the Total Environment, 521, 246-260.
Singh, R., Chadetrik, R., Kumar, R., Bishnoi, K., Bhatia, D., Kumar, A., Bishnoi, N.R., Singh, N. 2010. Biosorption optimization of lead (II), cadmium (II) and copper (II) using response surface methodology and applicability in isotherms and thermodynamics modeling. Journal of hazardous materials, 174(1-3), 623-634.
Sohbatzadeh Lonbar, H. 2016. Experimental investigation of operational parameters involved in uranium biosorption in fixed-bed columns using composite biosorbent of Pseudomonas-chitosan, PhD thesis. Amirkabir University of Technology & Nuclear Science and Technology Research Institute, .
Soudi, M.R., Tajer MohammadGhazvini, P., Khajeh, K., Gharavi, S. 2009. Bioprocessing of seleno-oxyanions and tellurite in a novel Bacillus sp. strain STG-83: A solution to removal of toxic oxyanions in presence of nitrate. Journal of hazardous materials, 165(1-3), 71-77.
Stolz, J., Basu, P., Oremland, R. 2002. Microbial transformation of elements: the case of arsenic and selenium. International Microbiology, 5(4), 201-207.
Tajer- Mohammad-Ghazvini, P. 2007. Study of microbial reduction of oxyanions under the condition of selenooxyanions–tellurite dual pollution, Master of Science Thesis. Alzahra University, Tehran, Iran.
Wadhwani, S.A., Shedbalkar, U.U., Singh, R., Chopade, B.A. 2016. Biogenic selenium nanoparticles: current status and future prospects. Applied microbiology and biotechnology, 100(6), 2555-2566.
Witek-Krowiak, A., Chojnacka, K., Podstawczyk, D., Dawiec, A., Pokomeda, K. 2014. Application of response surface methodology and artificial neural network methods in modelling and optimization of biosorption process. Bioresource Technology, 160, 150-160.
Yuan, Y., Zhu, J., Liu, C., Yu, S., Lei, L. 2015. Biomineralization of Se nanoshpere by Bacillus licheniformis. Journal of Earth Science, 26(2), 246-250.