تجزيه زيستي نفت خام توسط سيانوباكتري هاي فيشرلا (sp.ISC67 Fischerella) و نوستوك (Nostocsp sp. ISC101)

The crude oil biodegradation by Fisherella (Fischerella sp. ISC67 ) and Nostoc (Nostoc sp. ISC101) Cyanobacteria

ﻫﺪف از اﯾﻦ ﭘﮋوﻫﺶ، ﺗﻌﯿﯿﻦ رﺷﺪ و اﻣﮑﺎن ﺗﺠﺰﯾﻪ زﯾﺴﺘﯽ ﻧﻔﺖ ﺧﺎم ﺗﻮﺳﻂ ﺳﻮﯾﻪﻫﺎي ﺳﯿﺎﻧﻮﺑﺎﮐﺘﺮﯾﺎﯾﯽ ﻓﯿﺸﺮﻻ و ﻧﻮﺳﺘﻮك ﺑﻮد. در اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﺗﺠﺮﺑﯽ- آزﻣﺎﯾﺸﮕﺎﻫﯽ )ﺳﺎل 1393( ﻣﯿﺰان رﺷﺪ ﺳﻮﯾﻪﻫﺎي ﺳﯿﺎﻧﻮﺑﺎﮐﺘﺮﯾﺎﯾﯽ ﻓﯿﺸﺮﻻ )ISC107( و ﻧﻮﺳﺘﻮك )ISC101( ﺗﺤﺖ ﺗﯿﻤﺎرﻫﺎي ﻣﺨﺘﻠﻒ ﻧﻔﺖ ﺧﺎم )ﺷﺎﻫﺪ، 0/8 ،0/4 ،0/2 ،0/1 و 1/6 درﺻﺪ( ﺑﺎ اﻧﺪازهﮔﯿﺮي ﻣﺤﺘﻮاي ﮐﻠﺮوﻓﯿﻞ a در ﻃﻮلﻣﻮج 663 ﻧﺎﻧﻮﻣﺘﺮ ﺑﺮرﺳﯽ ﺷﺪ. ﻣﯿﺰان ﻏﻠﻈﺖ ﻧﻔﺖ ﺧﺎم ﭘﺲ از 21 روز ﺑﻪ روش ﮐﺮوﻣﺎﺗﻮﮔﺮاﻓﯽ ﮔﺎزي )GC-FID( ﺗﻌﯿﯿﻦ و ﻣﯿﺰان ﺗﺠﺰﯾﻪ زﯾﺴﺘﯽ ﻣﺤﺎﺳﺒﻪ ﮔﺮدﯾﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﺑﺎ اﻓﺰاﯾﺶ ﻏﻠﻈﺖ ﻧﻔﺖ ﺧﺎم ﻣﯿﺰان ﮐﻠﺮوﻓﯿﻞ a ﺑﻪﻃﻮر ﻣﻌﻨﯽداري ﮐﺎﻫﺶ ﯾﺎﻓﺖ و ﻧﺮخ رﺷﺪ اﯾﻦ ﺳﯿﺎﻧﻮﺑﺎﮐﺘﺮيﻫﺎ ﺑﺮ اﺳﺎس ﮐﻠﺮوﻓﯿﻞ a در ﺣﻀﻮر ﻧﻔﺖ ﺧﺎم ﺗﻘﺮﯾﺒﺎً ﺑﺮاﺑﺮ ﯾﺎ ﮐﻤﺘﺮ از ﻧﻤﻮﻧﻪ ﺷﺎﻫﺪ ﺑﻮد. ﺑﯿﺸﺘﺮﯾﻦ و ﮐﻤﺘﺮﯾﻦ ﻣﯿﺰان ﺗﺠﺰﯾﻪ ﻧﻔﺖ ﺧﺎم ﭘﺲ از 21 روز ﺑﻪ ﺗﺮﺗﯿﺐ در ﺗﯿﻤﺎرﻫﺎي 0/1 و 1/6 درﺻﺪ ﻧﻔﺖ ﺧﺎم ) ﻓﯿﺸﺮﻻ: 88/27 و 44/72 درﺻﺪ و ﻧﻮﺳﺘﻮك: 91 و 47/46 درﺻﺪ( ﻣﺸﺎﻫﺪه ﺷﺪ. ﺑﯿﻦ ﻣﻘﺎدﯾﺮ ﺗﺠﺰﯾﻪ در ﺗﻤﺎﻣﯽ ﺗﯿﻤﺎرﻫﺎي ﻣﻮردﺑﺮرﺳﯽ ازﻧﻈﺮ آﻣﺎري اﺧﺘﻼف آﻣﺎري ﻣﻌﻨﯽداري وﺟﻮد داﺷﺘﻪ و ﺗﻤﺎﻣﯽ ﺗﯿﻤﺎرﻫﺎ ﻧﺴﺒﺖ ﺑﻪ ﺷﺎﻫﺪ اﻓﺰاﯾﺶ ﻣﻌﻨﯽداري )0/05

The purpose of this study was to investigate the growth and potential of crude oil biodegradation by Fischerella and Nostoc. In this study (2015), the growth rate of cyanobacterial species such as Fischerella sp. ISC107 and Nostoc sp. ISC101 were determined using chlorophyll-a content measurement at 663nm under different treatments of crude oil (control, 0.1, 0.2, 0.4, 0.8 and 1.6%). The crude oil concentration was analyzed by gas chromatography (GC-FID) after 21 days, and also the biodegradation rate was determined. Results showed that by increasing the concentration of crude oil, the amount of chlorophyll-a was significantly decreased. So, the growth rate (based on chlorophyll-a) of these cyanobacteria were almost nearly equal or lower than the control sample in the presence of crude oil. The maximum and minimum percentages of crude oil biodegradation, in the treatments of 0.1 and 1.6% were 88.27% and 44.72% (Fischerella) and 91% and 47.46% (Nostoc), respectively after 21 days. The rate of biodegradation in all treatments was significantly (P<0.05) higher than control. According to results of this study, Fischerella ISC107 and Nostoc ISC 101 were shown great potential for crude oil biodegradation and can be used as valuable strains for biodegrading, elimination or the reduction of oil pollution in contaminated areas.