平欧榛子活性成分含量及抗氧化性比较

榛子中含有多种生物活性成分,不同品种、不同利用部位榛子的活性成分含量存在差异。以8个抗寒优良品种平欧榛子为原料,分别测定其种壳、种皮和种仁中总多酚、总黄酮、单宁及原花青素含量并对种皮中总多酚的抗氧化性进行评价。活性成分含量比较结果表明:种皮中各活性成分含量均显著高于种壳和种仁(P0.05);其中7#品种种皮总多酚含量最高,为185.76 mg/g;6#品种种皮总黄酮、单宁含量均为最高,分别为29.961、3 9.1 0 mg/g;7#品种原花青素含量最高,为7 7.2 8 mg/g;并且种皮中总多酚含量远高于其他3种活性成分(P0.05)。8种平欧榛子种皮总多酚的抗氧化性研究表明:综合考虑了不同质量浓度的处理效果,发现7#平欧榛子种皮总多酚抗氧化性效果强于其他品种,对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除率可达87.70%,对铁离子还原力为0.450,对超氧阴离子自由基清除率可达53.1%,对脂质过氧化的抑制率达到82.0%。种皮超氧阴离子自由基清除能力、DPPH自由基清除力、抑制脂质过氧化能力、对铁离子的还原能力与总多酚含量之间呈正相关,相关系数分别为0.843、0.793、0.695、0.620。

Comparison of Active Component Contents and Antioxidant Properties among Different Parts and Varieties of Flat European Hazelnut

Hazelnuts contain a variety of bioactive components, but the contents of bioactive components in hazelnuts vary depending on the variety and part. In the present study, eight cold-resistant varieties of flat European hazelnut were tested for the contents of bioactive components such as total polyphenols, total flavonoids, tannins and proanthocyanidins in shell, skin and kernel. The antioxidant activities of total polyphenols from hazelnut skin were determined. The results indicated that contents of bioactive components in skin were significantly higher than in shell and kernel (P < 0.05). Among the 8 varieties, the seed coat of the variety 7# had the highest contents of total phenolics and proanthocyanidins (185.76 and 77.28 mg/g, respectively), while the highest contents of total flavonoids and tannins (29.96 and 39.10 mg/g, respectively) were found in the seed coat of the variety 6#. Moreover, total phenolics were significantly more abundant than three other bioactives in hazelnut skin (P < 0.05). The antioxidant activity of seed coat polyphenols from 7# was better than that of any other variety. The percentage of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of total phenols from the skin of 7# was 87.70%, the ferric reducing power was 0.450, the percentage of superoxide anion radical scavenging activity was 53.1%, and the percentage of lipid peroxidation inhibition was 82.0%. The scavenging capacity against superoxide anion and DPPH radicals, the lipid peroxidation inhibition capacity, and the ferric reducing power of total phenolics from hazelnut skin were all positively correlated with total phenolics content with correlation coefficients of 0.843, 0.793, 0.695 and 0.620, respectively.