Diatom Culture and Analysis of Antioxidant Activity

• Main Authors: TIAN, YI-CIAN, 田怡茜
• Other Authors: LAI, SU-YUAN
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/54899085254780357093

碩士 === 中臺科技大學 === 食品科技系 === 105 === Diatoms are the most abundant species among the unicellular algae. Researches had shown that polysaccharides from diatoms have the effects of anti-oxidation and anti-cancer. TPC14 (Odontella sinensis) , diatoms collected from port of Taichung, was cultured using f/2 medium in the condition of 25 ℃, light/dark cycle 14/10 hours to establish its growth curve. They were also grown at various culture medium f、3/2f、2f、5f and L1 to find out the optimal culture condition and estimate its total carbohydrate contents by a phenol-sulfuric acid method. The methods of DPPH and ABTS for free radical scavenging effect were used to test the antioxidant activity of the carbohydrates. Our results showed that the highest cell numbers were reached 8.1 × 106 ± 1.5 cells/L at day 14 in medium f. The amount of extracellular soluble polysaccharides and extracellular adhesive polysaccharides obtained from diatom TPC14 were about 8.43 ± 1.54 mg/g biomass and 0.23 ± 0.01 mg/g biomass respectively. The amount of intracellular carbohydrates and the residual carbohydrates were 0.21 ± 0.04 mg/g biomass and 14.10 ± 0.25 mg/g biomass, respectively. Our results further demonstrated that the residual carbohydrates of diatom TPC14 had strong scavenging activities on DPPH radical (EC50= 89 ppm) and on ABTS radical (EC50= 140 ppm) in vitro.