Asyah Aghababaei - biology sciences, Alzahra University, Thehran, Iran
Parichehr Hanachi - Department of Biochemistry,Alzahra University, Thehran, Iran
Mostafa Noroozi - Department of Biotechnology ,Alzahra University, Thehran, Iran

Background and Aim:Monoraphidium it is a single-cellular algae, since microalgae is one of the major sources of new compounds with medicinal properties.The purpose of this study was to investigate the effects of three different temperatures (23, 28, 34˚c) on the growth, antioxidant property, total phenolic and flavonoid content at the end of the logarithmic stage monoraphidium, to increase the production of these valuable compounds was studied.Methods:For this purpose, samples were cultured in 2 L bottles containing 1.5 L of culture medium Bolds Basal Medium ; and under different temperatures treatment. Antioxidant assays were performed 16 days after the start of culture. After lyophilized, 10 mg of powder obtained, the cell mass was extracted by methanol solvent.Results:The results showed that the peak population density was obtained at 28 ˚c. The most antioxidant property in the frap method and the total phenol content at 28˚c were 127.65 µmol Fe2+ g-1± .036 antioxidant and8.06mgGAE g -1 ± .046 phenolic compounds, respectively. The maximum amount of flavonoids was reached at a temperature of 33 ˚c, at a rate of 54.37 mg quercetin g-1± .017. Although the temperature of 33 ˚c reduced the amount of biomass, but the percentage of flavonoids differs slightly from other temperatures.Conclusion:The findings of this study showed that increasing the temperature to 28˚c resulted in improved growth and increased antioxidant and total phenolic content. Based on the results of this research, temperature stress can be used to increase the production of antioxidants

Monoraphidium, Antioxidant property, Phenolic content, Flavonoid