ABSTRACT

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°C & 60°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°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°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°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.

摘要

玉米麸是一种研磨副产品，具有许多营养和功能特性。功能特性归因于一些生物活性化合物的存在。其中，阿魏酸是一种天然酚类化合物，大量存在于玉米麸皮中。它具有许多优点，并且通常在许多食品中具有营养特性。在目前的研究中，特别参考了不同的酚酸，探索了两种不同的玉米麸皮（PEARL-11 和 FSH-810）的营养和生物活性特征。此外，采用碱水解法从玉米麸中用NaOH提取阿魏酸，然后用乙醇沉淀提取。分别在 40°C 和 60°C 下使用两种不同浓度（0.5 M NaOH 和 1 M NaOH）优化提取方法，并进行分析以评估优化对提取率的影响。此外，通过高效液相色谱法(HPLC)分析获得的提取物。结果表明，与 FSH-810 相比，玉米麸皮 (PEARL-11) 含有更高的膳食纤维、总酚和类黄酮含量。此外，FSH-810 和 PEARL-11 中的 DPPH 和 FRAP 含量分别为 78% 至 86% 和 26.8 至 22.6 mg TE/100 g。HPLC 结果显示，在这些条件下（0.5 M NaOH 浓度；60°C 水解温度），玉米麸 (PEARL-11) 中阿魏酸的含量最高 (3.89 ± 0.07 mg/g)，而其他酚酸如二阿魏酸和 与 FSH-810 相比，总酚类和类黄酮含量。此外，FSH-810 和 PEARL-11 中的 DPPH 和 FRAP 含量分别为 78% 至 86% 和 26.8 至 22.6 mg TE/100 g。HPLC 结果显示，在这些条件下（0.5 M NaOH 浓度；60°C 水解温度），玉米麸 (PEARL-11) 中阿魏酸的含量最高 (3.89 ± 0.07 mg/g)，而其他酚酸如二阿魏酸和 与 FSH-810 相比，总酚类和类黄酮含量。此外，FSH-810 和 PEARL-11 中的 DPPH 和 FRAP 含量分别为 78% 至 86% 和 26.8 至 22.6 mg TE/100 g。HPLC 结果显示，在这些条件下（0.5 M NaOH 浓度；60°C 水解温度），玉米麸 (PEARL-11) 中阿魏酸的含量最高 (3.89 ± 0.07 mg/g)，而其他酚酸如二阿魏酸和在 0.5 M NaOH 浓度和 60°C 水解温度下，对香豆酸分别为 0.79 ± 0.012 和 0.42 ± 0.003 mg/g。此外，当水解温度为 60°C 时，NaOH 浓度为 (0.5) 的玉米麸 (PEARL-11) 中阿魏酸的提取率增加。最后，据观察，在其他谷麸中，玉米麸是不同酚酸（尤其是阿魏酸）的最便宜且天然丰富的来源。