松针多酚提取工艺优化及其抗氧化、酶活性抑制特征

Optimization of extraction process of polyphenols from pine needles and its antioxidant and enzyme activity inhibitory characteristics

为优化松针多酚的提取工艺,并考察其体外抗氧化作用以及对α-葡萄糖苷酶、α-淀粉酶、酪氨酸酶活性的抑制作用,本研究利用超声辅助提取法,在提取温度、提取时间、乙醇体积分数、液料比等要素对松针多酚提取单因素试验的基础上,利用响应面法优化松针多酚提取工艺;并利用优化工艺条件,测定了6种松科植物松针的多酚提取量。进一步利用不同多酚含量的松针提取液,分析松针多酚对1,1-二苯基-2-苦基肼自由基(DPPH)、2,2′-联氮-双-3-乙基苯并噻唑啉-6-磺酸自由基(ABTS+)、羟基自由基(·OH)的清除能力及其对α-葡萄糖苷酶、α-淀粉酶、酪氨酸酶活性的抑制能力。结果表明,松针多酚的最佳提取工艺为提取温度60℃、提取时间28 min、乙醇体积分数60%、料液比1 g∶25 ml;在此条件下,6种松科植物松针多酚提取量为19.97~53.41 mg/g。6种松科植物松针多酚对DPPH自由基清除的IC_(50)值范围为22.76~159.90μg/ml,对ABTS+自由基清除的IC_(50)值范围为0.092~0.184 mg/ml,对·OH自由基清除的IC_(50)值范围为2.176~8.134 mg/ml,对α-葡萄糖苷酶活性的抑制IC_(50)值范围为6.421~18.120μg/ml,对α-淀粉酶活性的抑制IC_(50)值范围为0.399~10.570 mg/ml,对酪氨酸酶活性的抑制IC_(50)值范围为0.121~3.725 mg/ml。总之,松针具有较高的多酚含量,明显的抗氧化活性,对α-葡萄糖苷酶、α-淀粉酶、酪氨酸酶活性有较强的抑制作用,在天然抗氧化剂、降糖药的研发中有广泛的应用前景。

In order to optimize the extraction process of pine needle polyphenols,and to investigate its antioxidant effect in vitro and its inhibitory effect on the activities ofα-glucosidase,α-amylase and tyrosinase,based on the single factor test of extraction temperature,extraction time,ethanol volume fraction and liquid-to-material ratio on the content of polyphenols in pine needle extract,the extraction process of pine needle polyphenols based on ultrasonic-assisted extraction was optimized by response surface method.The extraction of polyphenols from pine needles of six pine plants was determined by using the optimized process conditions.The scavenging ability of pine needle polyphenols on 1,1-diphenyl-2-picrylhydrazyl radical(DPPH),2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical(ABTS+)and hydroxyl radical(·OH)and their inhibitory ability on the activities ofα-glucosidase,α-amylase and tyrosinase were further analyzed by using pine needle extracts with different polyphenol contents.The results showed that the optimum extraction conditions were as follows:extraction temperature 60℃,extraction time 28 min,ethanol volume fraction 60%,liquid-solid ratio 1∶25(g∶ml).Under these conditions,the extraction amount of polyphenols from pine needles of six pine plants ranged from 19.97 mg/g to 53.41 mg/g.The IC_(50) values of DPPH free radical,ABTS+free radical,·OH free radical were 22.76-159.90μg/ml,0.092-0.184 mg/ml,2.176-8.134 mg/ml,respectively,and the IC_(50) values ofα-glucosidase,α-amylase and tyrosinase were 6.421-18.120μg/ml,0.399-10.570 mg/ml and 0.121-3.725 mg/ml,respectively.In summary,pine needles have high polyphenol content,obvious antioxidant activity,strong inhibitory effects on the activities ofα-glucosidase,α-amylase and tyrosinase,and have broad application prospects in the development of natural antioxidants and hypoglycemic drugs.