Effects of Combined Application of Rice Bran and Chemical Fertilizer on the Phytochemical Contents of Rice

The effect of rice bran (RB) applied alone or in combination with chemical fertilizer at different appli-cation rate on the phytochemical and antioxidant properties of rice was investigated. The treatments were 3 levels of RB namely: 200% RB (500 kg 10a-1), 100% RB (250 kg 10a-1), 50% RB (125 kg 10a-1), Recommended fertilizer dose (RF: N-P2O5-K2O, 11-5.5-4.8 kg 10a-1) combined with each RB, Half-recommended fertilizer dose (HRF: N-P2O5-K2O, 5.5-2.75-2.4 kg 10a-1) combined with each RB, RF and HRF applied at 1, 5, 10 days before rice transplanting (DBT). The parameters investigated were antioxidant, phytosterol and fatty acid contents. Results showed that the antioxidant pro-perty and phytosterol contents were high at 10 DBT HRF plus RB, 5 DBT RF plus RB, and 1 DBT 100 and 200% RB. However, total polyphenols increased from 10 to 1 DBT. In the case of fatty acids, no general trend was observed between treatments at different application times. Linoleic acid was high at 10 DBT HRF plus RB while linolenic acid was not affected at different application times. Palmitoeic and oleic acids were not also affected at 5 and 10 DBT. Saturated fatty acids were not also affected by any treat-ment at different application times except for palmitic acid. Most parameters obtained higher values at 100 and 200% RB treatments in 1 DBT.