In Vintro Atioxidant Activity of Stabilized Rice Bran and Its Fraction

Abstract

Some researches indicated that oryzanol had anboxldant actlvity, however, the information about the oryzanol role ln prevention of low dens~ty Iipoprote~n (LDL) and human lymphocyte from ox~dahon under oxidative stress was still I~mited The objecbve of this study was to invesl~gate the antiox~dant actlvlty of oryzanol at concentratlons based on rice bran beverage model ln preventing LDL and lymphocyte from oxidation Human plasma were supplemented wlth the samples of nce bran 011 [RBO), unsaponifiable matter and oryzanol IR-64, oryzanol IR-64 3x and oryzanol standard at the concentratlons of 308 3, 22 2, 5 2, 10 4 and 10 4 pglml, respectively Afterward, the human LDL were collected by ultracentnfuge and d~lutedu nbl a concentrat~ono f 200 pg prote~n/mlw as reached Human LDL lsolates were then oxidlzed with CuS04 5 /iM for measuring antloxldant activlty of the samples The length of incubation, H202 concentration, penod of sample supplemented Into human lymphocyte culture were determined before the antiox~dant actlvity of RBO and its fractlon in lymphocyte was measured The samples used in the lymphocyte were RBO IR-64, unsapon~f~abmlea tter 1/3-64, and oryzanol standard at the concentratlons of 133 2 - 2,132 0 ~rglml,9 6 - 153 6 lig/ml, and 2 4 - 37 7,ug/rnl, consecut~vely The result showed that malonaldehyde concentration m human LDL decreased significantly (~s= 0 05), 15 - 41°0 and 39 - 56 % compared to the control The absorbance of 11v1ngly mphocyte cell ln culture was not influenced by the type and concentrat~ono f RE0 and its fracbon The addltlon of hydrogen peroxlde (Hz04 3 mM into culture s~gnlf~cantlloyw ered the absorbance as compared to culture w~thoutH 202