نوع مقاله : پژوهشی- فارسی
نویسندگان
1 گروه بیوتکنولوژی، دانشکده علوم و فناوری های همگرا، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران
2 گروه زیست شناسی، دانشگاه آزاد اسلامی، واحد علوم و تحقیقات، تهران، ایران
3 گروه میکروبیولوژی، دانشکده علوم و فناوری های نوین، دانشگاه علوم پزشکی آزاد اسلامی، تهران، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Introduction: Production of exopolysaccharides (EPS) by cyanobacteria in response to heavy metal stress is one of the important features of these microorganisms in the biological treatment of polluted waters. In this research, the ability of two soil and freshwater cyanobacteria Nostoc punensis and Neowestiellopsis Persica A1387 to remove heavy metals chromium, nickel and copper has been investigated.
Materials and Methods: After the growth of cyanobacteria Nostoc punensis and Neowestiellopsis Persica A1387 in BG-110 culture medium in the growth chamber, inoculation of the medium containing heavy metals was performed. Then, the rate of removal of heavy metals in a 90-minute time efficiency along with the measurement of dry weight, carbohydrates, protein and exopolysaccharides evaluated. In addition, Raman and Fourier transform infrared spectrometry (FTIR) and gas chromatography-mass spectrometry (GC-MS) for the identification of effective functional groups and volatile compounds effective in removing heavy metals performed.
Discussion: The results of the one-way analysis of variance and Tukey's test showed that the highest amount of cell dry weight, exopolysaccharide, carbohydrate, and protein were found in the Neowestiellopsis Persica A1387 strain exposed to nickel and chromium metals. In addition, the results of atomic absorption of heavy metals showed that the Neowestiellopsis Persica A1387 strain showed the highest amount of nickel metal removal (350 mg. dry weight-1) in the first ten minutes. The results of FTIR showed that in the regions of 405 cm-1, 575 cm-1, and 813-920 cm-1 peaks were found in connection with C-N and carbonyl (C=O) bending groups, which observed only when exposed to heavy metals.
Conclusion: Aquatic cyanobacteria Neowestiellopsis sp. showed more resistance than soil cyanobacteria Nostoc sp. in metal treatments (copper, nickel and chrome).
کلیدواژهها [English]