BIOCHEMICAL PROPERTIES OF MAIZE BRAN WITH SPECIAL REFERENCE TO DIFFERENT PHENOLIC ACIDS

Maize bran is a milling by-product having many nutritional and functional properties. Functional properties are attributed to the presence of some bioactive compounds. Among those, ferulic acid is a natural phenolic compound and abundantly present in maize bran. It has numerous advantages and generally has nutraceutical properties in many food products. In the current research, the nutritional & bioactive profiles of two different maize brans (PEARL-11and FSH-810) were explored with special reference to different phenolic acids. Moreover, the alkaline-hydrolysis method was used to extract ferulic acid from maize brans using NaOH and then extracted by precipitating with ethanol. The extraction method was optimized using two different concentrations (0.5 M NaOH and 1 M NaOH) at 40 degrees C & 60 degrees C, respectively, and was analyzed to evaluate the optimization effects on extraction yield. Furthermore, obtained extracts were analyzed by High-Performance Liquid Chromatography (HPLC). Results showed that maize bran (PEARL-11) contains higher dietary fiber, total phenolic and flavonoid contents as compared to FSH-810. Moreover, DPPH and FRAP contents ranged from 78 to 86% and 26.8 to 22.6 mg TE/100 g in FSH-810 and PEARL-11, respectively. HPLC results showed maximum amount of ferulic acid (3.89 +/- 0.07 mg/g) in maize bran (PEARL-11) at these conditions (0.5 M NaOH concentration; 60 degrees C hydrolysis temperature) whilst other phenolic acids such as diferulic and p-coumaric acid were 0.79 +/- 0.012 and 0.42 +/- 0.003 mg/g at 0.5 M NaOH concentration and 60 degrees C hydrolysis temperature, respectively. Furthermore, the extraction yield of ferulic acid from maize bran (PEARL-11) of NaOH concentration (0.5) with hydrolysis temperature (60 degrees C) was increased. Conclusively, it is observed that maize bran is the cheapest and naturally rich source of different phenolic acids (especially ferulic acid) among other cereal bran.