نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار ، بخش میکروبیولوژی، گروه زیست شناسی، دانشکده علوم، دانشگاه اصفهان

2 استاد، بخش میکروبیولوژی، گروه زیست شناسی، دانشکده علوم، دانشگاه اصفهان

چکیده

در تحقیق حاضر مخمر بومی مولد چربی به نام Rhodotorula mucilaginosa سویه UIMC35 جهت تولید روغن تک یاخته جداسازی و شناسایی گردید. تکنیک فلوسایتومتری جهت بررسی میزان شدت فلورسنت سلولی (در کانال FL2)، اندازه سلولی (با پارامتر FSC) و تراکم درون سلولی (با پارامتر SSC) به کار گرفته شد. رابطه بین شدت فلورسنت و محتوای لیپیدی، جهت محاسبه سریع و آسان میزان محتوای لیپیدی ارائه گردید. تغییرات فاکتورهای مختلف همچون میزان تولید لیپید و بیومس، محتوای لیپیدی، کارایی تولید لیپید و بیومس، میزان قند، میزان ازت، نسبت کربن به ازت و pH در مراحل مختلف رشد مخمر در کشت بسته مورد بررسی قرار گرفت. بیشترین میزان تولید لیپید، محتوای لیپیدی و کارایی تولید لیپید در مخمر مورد بررسی به ترتیب 57/6 گرم در لیتر، 04/67 درصد و 13/21 درصد بدست آمد. کاهش نسبت C/N در مراحل انتهایی کشت از عوامل تاثیر گذار در کاهش میزان تولید لیپید به شمار می رود.

کلیدواژه‌ها

عنوان مقاله [English]

Monitoring lipid production in growth phases of new isolated oleaginous yeast Rhodotorula mucilaginosa strain UIMC35 by flow cytometry

نویسندگان [English]

  • Hossein Ghanavati 1
  • Iraj Nahvi 2

چکیده [English]

In present study, oleaginous yeast Rhodotorula mucilaginosa strain UIMC35 was isolated and identified for SCO (single Cell Oil) production. Flow cytometric technique was employed for the monitoring of fluorescence intensity of the cells (channel FL2), cell size (by FSC parameter) and the cell granularity (by SSC parameter). The relationship between fluorescence intensity and lipid content in order to quick and easy calculation of the amount of lipid content was presented. Changes in various factors such as lipid and biomass production, lipid content, lipid and biomass production efficiency, the amount of sugar, the amount of nitrogen, C/N ratio and pH were investigated at different stages of yeast strain batch culture. The highest rates of lipid production, lipid content and lipid production efficiency by this yeast strain were achieved 6.57 g/l, 67.04 % and 21.13 %, respectively. Decreasing of C/N ratio in the later stages of yeast growth caused the reduction of the lipid production rate.

کلیدواژه‌ها [English]

  • Oleaginous yeast
  • Flow cytometry
  • Fluorescent intensity
  • Lipid content
  • Subpopulation
 
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