梨中不同形态酚类化合物的抗氧化活性对比分析

Extraction and Antioxidant Activity of Polyphenols from Pear

本文采用溶剂提取法对梨皮和梨肉中的自由酚和结合酚进行提取,并采用DPPH法测量梨皮及梨肉的抗氧化活性。研究结果表明,梨皮中总酚含量为(201.26±6.90)×10-2mg/g鲜梨(以没食子酸计),其中自由酚为135.36±1.57 mg;结合酚为42.46±3.05 mg;梨肉中总酚含量为(23.73±2.28)×10-2mg/g鲜梨肉(以没食子酸计),其中自由多酚含量为12.54±0.98 mg,结合酚11.19±1.30 mg。黄酮含量与多酚含量呈良好正相关。通过比较梨皮梨肉中两种自由酚抗氧化活性,得出梨肉自由酚的抗氧化活性最高,DPPH清除率的EC50为248.59μg/mL,AE值为0.0040;梨肉结合酚的抗氧化活性较低低,DPPH清除率的EC50为1043.24μg/mL,AE值为0.0010。

This study was designed to investigate the extraction of free and bound phenol from the peels and the flesh of pear by solvent extraction method. The antioxidant activity of the peels and the flesh was also studied using the DPPH. assay. The results showed that the total phenol in peels was 201.264-6.90 mg gallic acid equivalents per 100 g fresh pear peels, including 135.36i-1.57 mg soluble free phenol and the 42.464-3.05 mg bound phenol. And the total phenol in the flesh was lower with the value of 23.734-2.28 mg gallic acid equivalents per 100 g fresh pear flesh, including 12.544-0.98 mg soluble free phenol and 11.194-1.30mg bound phenol. The content of the flavonoid had a positive correlation with the content of the total phenol. Comparing the antioxidant activities of the peels and fresh, the free phenol in pear flesh had the highest antioxidant activity, with the values of DPPH. scavenging rate ECs0 and AE being of 248.59 ixg/mL and 0.0040, respectively. The bound phenol in the pear fresh had the lowest antioxidant activity, with the values of DPPH. scavenging rate ECs0 and AE being of 1043.24 txg/mL and 0.0010, respectively.