| Abstract | Five varieties of black glutinous rice and controlled white rice varieties were investigated the quantity analysis of neutraceutical antioxidants as ,B-carotene, y-oryzanol and a-tocopherol. Before analysis, two parts of paddy separated by milling and polishing process into mixed bran and inner seed were collected. In ,8-carotene determination, liquid chromatography technique was performed to examine the amount of ,8-carotene component in mixed bran and inner seed parts. Result showed that black glutinous rice varieties had much higher ,B-carotene content than controlled white rice varieties. As Khao Niaw Dam No.17 had the highest ,B-carotene amount of 21.67 µgig sample in mixed bran part, while Ang Kaew 1 had the highest value of 1.11 µ gig sample in inner seed part. Spectrophotometer technique also was performed to determine ,B-carotene component, but results indicate that there were some limitations by using this technique especially at low concentration. For the determination of y-oryzanol, crude oil was extracted from the mixed bran part of five black glutinous rice and one controlled white rice varieties. After determinations of optimum conditions, thin layer chromatography technique was applied to first check the amount of y-oryzanol component by using mobile phase of hexane/diethyl ether/acetic acid (60:40:1). After applying of high performance liquid chromatography technique, result indicated that Khao Niaw Dam No.18 contained the highest amount of y-oryzanol of 3,594 ppm and Niaw San Pah Thong (a white rice variety) contained 1,088.5 ppm when using hexane as crude oil extractant. Hence, the y-oryzanol content depends on the variety of rice and not on whether it is white or black rice varieties. Partial purification of y-oryzanol from commercial crude rice bran oil and crude oil from mixed bran of Khao Niaw Dam No.18 also was performed and result showed that the purified droplet presented y-oryzanol component of 33.4% and 29.1 % respectively. The determination of a-tocopherol content in crude oil was done at the same time with y-oryzanol determination. Result indicated that when using iso-propanol as crude oil extractant, CMU-98-1-1 contained the highest amount of a-tocopherol of 187.6 ppm and Niaw San Pah Thong (a white rice variety) had 59.6 ppm respectively. These results indicated that besides the consumable part of black glutinous rice, rice milling byproducts liked mixed bran and crude rice bran oil also had considerable amounts of valuable neutraceuticals liked ,B-carotene, y-oryzanol and a-tocopherol. |