Isolation, purification and anti-oxidation of ribosome-inactivated proteins from seeds of Momordica charantia L.
FU Ming hui, TIAN Jie (Department of Biology,Shantou University,Shantou 515063,China)
PurposeTo improve the isolating technology of ribosome inactivating protein of Momordica charantia and to study their anti oxidatiion activity. MethodsThe seeds of Momordica charantia were smashed and isolated with 50 mmol/L acetic acid, precipitated with (NH 4) 2SO 4 and purified by CM32,Sephadex G 75 column chromatography. The physical and chemical characters of two ribosome inactivating proteins were identified.ResultsAfter purifying, one kind of protein whose molecular weight was 29.6 kD and other,below 10.0 kD were obtained. 29.6 kD protein had inhibitory action upon protein synthesis in reticulocyte lysate and its IC 50 was 4.3×10 -6 mol/L, and the small molecular weight protein was 1.4×10 -6 mol/L. The sugar content of 29.6 kD protein was 4.83% and the small protein was 1.82%. The semi SOD activity of 29.6 kD was 79.05 u/mg protein, and the semi SOD activity of the small protein was 17.25 u/mg protein. The positive contrast of the activity of pure SOD was 1 267 u/mg protein. ConclusionTwo kinds of proteins had different molecular weights were isdated and purified. These two kinds of protein were glycoprotein, and had some anti oxidation activity.