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Production of Heterologous Protein from Pichia pasteris by Air Lift Bioreactor
Choi, Du Bok,Kim, Sun Il 한국공업화학회 2005 Journal of Industrial and Engineering Chemistry Vol.11 No.3
For high-level expression of heterologous protein using a methylotrophic yeast, P. pastoris, in an air lift bioreactor, the initial methanol concentration and inoculation time were investigated. When 30 g/L of methanol was used, α-amylase activity was highest (235 U/mL). When the inoculation was carried out at 18 hr of culture, the maximum α-amylase activity was obtained (270 U/mL) and the consumed methanol concentration was 24.S g/L. The α-amylase activity expressed in P. pastrris was stable up to 50℃ and showed 86.4% of residual activity at 60℃. However. in the case of S. cererisiae, it remained only 57.3% under the same conditions. Between pH 6 and 7, the mouse α-amylase activity expressed in P. pcesteris was stable. However, in the case of S. cerehiciae, it was stable between pH 7 and 8. Using the optimum culture conditions, the fed cultures were carried out for 4 days. The methanol consumption increased upon culture time up to 3 day s, but after 4 days it began to decrease. The cell concentration was similar to that of S. cerevisiae. The maximum α-amylase activity was 610 U/mL at 4 days of culture; this value was about 6.0-fold higher than that of S. cerevisiae. In the case of product yield from methanol, it was 15.2 U/mL/g the consumed carbon source, which was about 11.5-fold higher than that of S. cerevisiae using glucose.
Effects of Fomitopsis pinicola Extracts on Antioxidant and Antitumor activities
Choi, Du-Bok,Park, Sang-Shin,Ding, Ji-Lu,Cha, Wol-Suk Korean Society for Biotechnology and Bioengineerin 2007 Biotechnology and Bioprocess Engineering Vol.12 No.5
We investigated the effects of Fomitopsis pinicola extract on biological activity by examining the antioxidant and antitumor activity in vitro and in vivo. When the F. pinicola extract concentration was raised from 60 to $120{\mu}g/mL$, the DPPH scavenging rate increased from 50.3 to 88.2% and the superoxide anion radical scavenging rate increased from 45.2 to 85.3% when the F. pinicola extract concentration was raised from 500 to $700{\mu}g/mL$. After incubating F. pinicola extract for 12 h, the linoleic acid scavenging rate increased from 35.5 to 90.5%. A similar finding was observed for butylated hydroxytoluene. The total phenolic content of the F. pinicola extracts were approximately 10- to 16-fold higher than what was observed in the P. nebrodensis and A. camphorate extracts. The glutathione production, using decoctions prepared from F. pinicola, was $20.0{\mu}M/g$ of liver, which corresponded to approximately 4.0-fold higher than the control. The glutathione peroxidase activity was 8.3 U/mg of protein, which was approximately 2.8-fold higher than the activity level observed in the control rat livers. The cell viability rates of all the human cancer cells, when $100{\mu}g/mL$ of ethanol extract was used for the different types of cancer cells, decreased with increasing extract concentrations in comparison to the hot water extract. In particular, when HeLa and Hep3B cells were incubated with $1000{\mu}g/mL$ of methanol extract, the cell viability rates were 20 and 25%, respectively, which was approximately 3.0-fold higher than what was observed for the hot water extract.