Departamento de Agroindústria, Alimentos e Nutrição, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Av. Pádua Dias 11, Piracicaba, São Paulo, Brazil.
Plant Foods Hum Nutr. 2012 Sep;67(3):262-70. doi: 10.1007/s11130-012-0298-9.
Intervention strategies regarding the biofortification of orange-fleshed sweet potato, which is a rich source of carotenoids for combating vitamin A deficiency, are being developed in Brazil. This study was conducted to evaluate the concentrations of individual carotenoids, total phenolic compounds and antioxidant capacity in the roots of four biofortified sweet potato cultivars that were raw or processed by four common heat treatments. HPLC, Folin-Ciocalteu, DPPH and ABTS assays were used. All cultivars showed high levels of carotenoids in raw roots, predominantly all-trans-β-carotene (79.1-128.5 mg.100 g(-1) DW), suggesting a high estimated vitamin A activity. The CNPH 1194 cultivar reported carotenoids values highest than those of other cultivars (p < 0.05). The total phenolic compounds varied among cultivars and heat treatments (0.96-2.05 mg.g(-1) DW). In most cases, the heat treatments resulted in a significant decrease in the carotenoids and phenolic compounds contents as well as antioxidant capacity. Processing of flour presented the greatest losses of major carotenoids and phenolics. The phenolic compounds showed more stability than carotenoids after processing. There were significant correlations between the carotenoids and phenolic compounds and the antioxidant capacity.
巴西正在制定针对富含类胡萝卜素的橙色甘薯（可有效防治维生素 A 缺乏症）的生物强化策略。本研究旨在评估四种生物强化甘薯品种的根部分离物的类胡萝卜素、总酚化合物和抗氧化能力的浓度，这些品种经过四种常见热处理方法的加工。采用高效液相色谱法（HPLC）、福林-酚试剂比色法、DPPH 和 ABTS 法进行分析。所有品种的生薯根中均含有高水平的类胡萝卜素，主要为全反式-β-胡萝卜素（79.1-128.5mg.100g(-1) DW），表明其具有较高的维生素 A 活性。CNPH 1194 品种的类胡萝卜素含量高于其他品种（p < 0.05）。总酚化合物在品种和热处理之间存在差异（0.96-2.05mg.g(-1) DW）。在大多数情况下，热处理会导致类胡萝卜素、酚类化合物含量以及抗氧化能力显著下降。加工成面粉会导致主要类胡萝卜素和酚类化合物的大量损失。加工后，酚类化合物比类胡萝卜素更稳定。类胡萝卜素和酚类化合物与抗氧化能力之间存在显著相关性。
