Developing a nutraceutical from Egyptian stabilized rice bran: a pharmacological approach
Rice bran is known to contain bioactives which are potentially useful for human health. These include the tocotrienols, policosanol and gamma-oryzanol. Rice bran has been stabilized immediately after collection from the milling stations in order to preserve the integrity of its active constituents. An extract of the stabilized rice bran has been prepared and standardized to contain 2% g-oryzanol. The extract has been subjected to a battery of pharmacological testing to establish its potential therapeutic usefulness. When given orally in doses of 30 and 100mg/kg for 1 week to rats which had been rendered hypertensive by L-NAME, the extract was shown to protect against the rise in blood pressure without affecting the heart rate of animals. Equally, in the same oral doses, it was shown to be effective as an anti-inflammatory in models of acute (carrageenan paw edema) and chronic inflammation (adjuvant-induced arthritis) in rats. It also reduced the level of inflammatory mediators and cytokines in the blood. The extract also showed good anti-oxidant activity as measured in various in vitro as well as in vivo models and has a beneficial effect on insulin secretion in in vitro models and in preliminary animal experiments. Safety studies on the extract in rats showed its lack of toxic side effects over a prolonged period of time. The present results point to the potential usefulness of the extract as a nutraceutical to guard against inflammatory disorders, hypertension, and diabetes.
Keywords: rice bran, nutraceuticals, diabetes, hypertension, anti-inflammatory, herbal drugs