School of Biotechnology, International University, Vietnam National University, Quarter 6, Linh Trung Ward, Thu Duc District, HoChiMinh City, Vietnam; Wheat Enzymes and Asian End Product, Grain Research Laboratory, Canadian Grain Commission, 1404-303 Main Street, Winnipeg, MB, Canada R3C 3G8.
Wheat Enzymes and Asian End Product, Grain Research Laboratory, Canadian Grain Commission, 1404-303 Main Street, Winnipeg, MB, Canada R3C 3G8.
Food Chem. 2011 Jun 15;126(4):1896-901. doi: 10.1016/j.foodchem.2010.12.015. Epub 2010 Dec 10.
The phenolic acid profiles of flours from two Canadian wheat classes, Canadian Western Red Spring (CWRS) and Canadian Western Amber Durum (CWAD), were investigated using two different extraction mediums and analysed on an ultra-performance liquid chromatography (UPLC) system at different degrees of sprout damage. A sound (non-sprouted) control sample as well as two different sprouted sub-samples, derived from different germination protocols of the control, were prepared for both the CWAD and CWRS. Free phenolic acids were extracted from the ground whole wheat meal using three repetitive 80% ethanol extractions. Bound phenolic compounds were subsequently released from the residue by alkaline hydrolysis followed by triplicate extraction with diethyl ether:ethyl acetate (1:1, v/v). Twelve phenolic acid standards were clearly resolved and quantified using a short 5min elution gradient. Seven phenolic acids (4-hydroxybenzoic, vanillic, caffeic, syringic, p-coumaric, ferulic and sinapic) were detected in the CWRS and CWAD alcoholic and alkaline extracts. Syringic acid was the main compound in the free phenolic alcoholic extracts of the wheat meal representing 77.0% and 75.3% of the total amount of detected free phenolic compounds for CWRS and CWAD, respectively. However, the major released phenolic compound detected in the alkaline hydrolysed extracts was ferulic acid accounting for 72.3% and 71.0% for CWRS and CWAD respectively total bound phenolics. During germination, syringic acid levels rose as the length of germination time increased, resulting in the increase in total phenolic compound and antioxidant activity of the sprouted wheat flours. There was an increase in total phenolic compounds and the antioxidant activity of the alcoholic extracts from the CWRS and CWAD wheat flours as the germination time was extended. As a result, the sprouted wheats exhibits better nutritional properties than un-germinated wheat and could be used to improve the nutrition value in food products.
研究了两种加拿大小麦品种（加拿大西部红春小麦（CWRS）和加拿大西部琥珀硬质春小麦（CWAD））的面粉中的酚酸谱，使用了两种不同的提取介质，并在不同发芽损伤程度下在超高效液相色谱（UPLC）系统上进行了分析。为 CWAD 和 CWRS 制备了一个健全（未发芽）对照样品以及两个不同发芽亚样品，这两个亚样品来自对照的不同发芽方案。将整粒小麦粉用三种重复的 80%乙醇提取法从地面提取游离酚酸。然后，通过碱性水解将结合酚类化合物从残渣中释放出来，然后用二乙醚：乙酸乙酯（1：1，v/v）重复提取三遍。使用短的 5min 洗脱梯度可清晰分辨和定量 12 种酚酸标准品。在 CWRS 和 CWAD 醇提和碱提物中检测到 7 种酚酸（4-羟基苯甲酸、香草酸、咖啡酸、丁香酸、对香豆酸、阿魏酸和芥子酸）。丁香酸是小麦粉游离酚醇提取物中的主要化合物，分别占 CWRS 和 CWAD 游离总酚类化合物的 77.0%和 75.3%。然而，在碱性水解提取物中检测到的主要释放酚酸是阿魏酸，占 CWRS 和 CWAD 总结合酚的 72.3%和 71.0%。在发芽过程中，随着发芽时间的延长，丁香酸水平升高，导致发芽小麦粉中总酚类化合物和抗氧化活性增加。随着发芽时间的延长，CWRS 和 CWAD 小麦粉的醇提物中的总酚类化合物和抗氧化活性增加。因此，发芽小麦比未发芽小麦具有更好的营养特性，可以用于提高食品中的营养价值。
