ABSTRACT
Rice bran (RB) is one of the nutrient-rich agricultural byproducts. It is a composite of carbohydrates, lipids, proteins, fibers, minerals, and trace elements such as phosphorus, potassium, magnesium, calcium and manganese. The extraction and purification process influences the quality and quantity of rice bran oil, which is rich in tocopherols, tocotrienols, γ-oryzanol, and unsaturated fatty acids. The bioactive components of RB have been reported for exhibiting antioxidant, anti-inflammatory, hypocholesterolemic, anti-cancer, anti-colitis, and antidiabetic properties. In vitro and in vivo studies, and clinical trials in human volunteers revealed the anti-hyperglycemic activity of RB derived compounds. An updated comprehensive review on the antidiabetic property of RB and its derivative is required to appraise the current knowledge in the particular field. Thus, the present paper covered the composition and bioactivities of RB, and influence of extraction methods on the biological property of rice bran oil and rice bran extract. And the current review also focused on the reported anti-hyperglycemia activity of rice bran derivatives, and its probable mechanism.
ABSTRACT
Rice bran (RB) is one of the nutrient-rich agricultural byproducts.It is a composite of carbohydrates,lipids,proteins,fibers,minerals,and trace elements such as phosphorus,potassium,magnesium,calcium and manganese.The extraction and purification process influences the quality and quantity of rice bran oil,which is rich in tocopherols,tocotrienols,γ-oryzanol,and unsaturated fatty acids.The bioactive components of RB have been reported for exhibiting antioxidant,anti-inflammatory,hypocholesterolemic,anti-cancer,anti-colitis,and antidiabetic properties.In vitro and in vivo studies,and clinical trials in human volunteers revealed the anti-hyperglycemic activity of RB derived compounds.An updated comprehensive review on the antidiabetic property of RB and its derivative is required to appraise the current knowledge in the particular field.Thus,the present paper covered the composition and bioactivities of RB,and influence of extraction methods on the biological property of rice bran oil and rice bran extract.And the current review also focused on the reported antihyperglycemia activity of rice bran derivatives,and its probable mechanism.
ABSTRACT
Drought-tolerant cultivars and their phytochemical composition, which has a role in providing drought tolerance are gaining importance. In this study, rice bran oil and semi-purified oryzanol (SPO) obtained from five rice (Oryza sativa L.) cultivars, namely P1401 and PB1 (drought-susceptible) and N22, PNR381 and APO (drought-tolerant) were analyzed for the γ-oryzanol content, an antioxidant present in considerable amount in the rice bran. The higher level of γ-oryzanol and its antioxidant activity was observed in drought-tolerant cultivars (N22, PNR381 and APO) as compared to drought-susceptible (PB1 and P1401), suggesting the role of γ-oryzanol in drought tolerance, as antioxidants are known to play an important role by scavenging free radicals. The total antioxidant activity of γ-oryzanol might be attributed to 24-methylene cycloartanyl ferulate, a major component of γ-oryzanol. By enhancing the level of active oryzanol components identified in this study by genetic and molecular means could impart increased drought tolerance.
Subject(s)
Antioxidants/metabolism , Droughts , Oryza/cytology , Oryza/metabolism , Oryza/physiology , Phenylpropionates/isolation & purification , Phenylpropionates/metabolism , Plant Oils/metabolismABSTRACT
<p><b>OBJECTIVE</b>To develop and validate an image analysis method for quantitative analysis of γ-oryzanol in cold pressed rice bran oil.</p><p><b>METHODS</b>TLC-densitometric and TLC-image analysis methods were developed, validated, and used for quantitative analysis of γ-oryzanol in cold pressed rice bran oil. The results obtained by these two different quantification methods were compared by paired t-test.</p><p><b>RESULTS</b>Both assays provided good linearity, accuracy, reproducibility and selectivity for determination of γ-oryzanol.</p><p><b>CONCLUSIONS</b>The TLC-densitometric and TLC-image analysis methods provided a similar reproducibility, accuracy and selectivity for the quantitative determination of γ-oryzanol in cold pressed rice bran oil. A statistical comparison of the quantitative determinations of γ-oryzanol in samples did not show any statistically significant difference between TLC-densitometric and TLC-image analysis methods. As both methods were found to be equal, they therefore can be used for the determination of γ-oryzanol in cold pressed rice bran oil.</p>
ABSTRACT
Objective: To develop and validate an image analysis method for quantitative analysis ofγ-oryzanol in cold pressed rice bran oil.Methods:TLC-densitometric and TLC-image analysis methods were developed, validated, and used for quantitative analysis of γ-oryzanol in cold pressed rice bran oil. The results obtained by these two different quantification methods were compared by paired t-test.Results:Both assays provided good linearity, accuracy, reproducibility and selectivity for determination of γ-oryzanol. Conclusions: The TLC-densitometric and TLC-image analysis methods provided a similar reproducibility, accuracy and selectivity for the quantitative determination of γ-oryzanol in cold pressed rice bran oil. A statistical comparison of the quantitative determinations of γ-oryzanol in samples did not show any statistically significant difference between TLC-densitometric and TLC-image analysis methods. As both methods were found to be equal, they therefore can be used for the determination of γ-oryzanol in cold pressed rice bran oil.