作 者：
王彦兵;王晓媛;肖兵;尹红星;刘小琼;张洪波;戴余波;李锦红
关键词：
咖啡果皮;总黄酮;提取工艺;响应面;抗氧化活性
摘 要：
【目的】优化咖啡果皮总黄酮的超声波辅助提取工艺条件,并分析其体外抗氧化活性,为咖啡果皮的综合利用提供理论基础。【方法】以小粒咖啡果皮为原料、乙醇溶液为提取剂,在单因素试验的基础上,以乙醇体积分数、料液比、超声波时间和超声波温度4个因素为自变量,咖啡果皮总黄酮提取率为响应值,采用Box-Behnken试验设计方法,研究各自变量及其交互作用对咖啡果皮总黄酮提取率的影响,确定最佳提取工艺,并比较咖啡果皮总黄酮和L-抗坏血酸的抗氧化活性。【结果】4个因素对咖啡果皮总黄酮提取率的影响排序为超声波时间>料液比>乙醇体积分数>超声波温度,其中乙醇体积分数、料液比和超声波时间对总黄酮提取率有极显著影响(P<0.01),超声波时间与超声波温度的交互作用对总黄酮提取率有显著影响(P<0.05)。咖啡果皮总黄酮提取工艺条件经优化后为:乙醇体积分数41%、料液比1∶46(g/mL)、超声波时间44 min、超声波温度60℃,在此条件下,得到的实际提取率(6.99±0.02)%与预测值(7.02%)的相对误差小。咖啡果皮总黄酮对1,1-二苯基-2-三硝基苯肼(DPPH)自由基和羟自由基有一定的清除能力,其半清除浓度(IC50)分别为3.93和297.23μg/mL,清除能力分别是L-抗坏血酸的61%和17%。咖啡果皮总黄酮具有一定还原力,还原力随质量浓度增加而增强。【结论】响应面法优化超声波辅助提取咖啡果皮总黄酮工艺切实可行,建立的回归模型拟合度和重现性较好,提取的总黄酮具有一定抗氧化能力。咖啡果皮可作为一种天然抗氧化剂来源在食品、医药等方面进行开发利用。
译 名：
Optimization of extracting total flavonoids from Coffea arabica peel and its antioxidant activity in vitro
作 者：
WANG Yan-bing;WANG Xiao-yuan;XIAO Bing;YIN Hong-xing;LIU Xiao-qiong;ZHANG Hong-bo;DAI Yu-bo;LI Jin-hong;Dehong Tropical Agriculture Institute of Yunnan;
关键词：
coffee peel;;total flavonoids;;process optimization;;response surface analysis;;antioxidant activity
摘 要：
【Objective】The optimization of process parameters for ultrasonic-assisted extraction of total flavonoids from Coffea arabica(coffee)peel was investigated in this study. Meanwhile,the antioxidant activity in vitro was studied to provide a theoretical basis for the comprehensive utilization of coffee peel.【Method】Using coffee peel as raw material,ethanol solution as the extraction agent,coffee peel total flavonoids extraction yield as the response value,based on singlefactor tests,Box-Benhnken center composite experiment was carried out with four factors,including ethanol volume fraction,solid-liquid ratio,ultrasonic time and ultrasonic temperature. Studying the effects of each variable and its interaction on the extraction rate of total flavonoids from coffee peel,determining the optimum extraction technology and comparing the antioxidant activity of total flavonoids in coffee peel with that of L-ascorbic acid.【Result】The effects of four factors on the extraction rate of total flavonoids from coffee peel was as follows:ultrasonic time>solid-liquid ratio>ethanol volume fraction>ultrasonic temperature. Ethanol volume fraction,solid-liquid ratio and ultrasonic time had extremely significant influence on total flavonoids yield(P<0.01). The interaction between ultrasonic time and ultrasonic temperature had significant influence on total flavonoids yield(P<0.05). The optimum technology conditions of total flavonoids from coffee peel were obtained as follows:ethanol volume fraction 41%,solid-liquid ratio 1∶46 g/mL,ultrasonic time 44 min,ultrasonic temperature 60 ℃. Under the above optimum conditions,the total flavonoids content of coffee peel reached up to(6.99±0.02)%,which was close to the theoretical value(7.02%). Antioxidant evaluation showed that coffee peel flavonoids had certain scavenging abilities towards 1, 1-diphenyl-2-picrylhydrazyl(DPPH)and hydroxyl free radical,and the cleanrance abilities were 61% and 17% of L-ascorbic acid,with the half cleanrance concentration(IC50)values being of3.93 μg/mL and 297.23 μg/mL. The total flavones of coffee peel had certain reducibility,and the reducing power increased with the increase of mass concentration.【Conclusion】The response surface method can optimize the ultrasonic assisted extraction of total flavonoids from coffee peel,and the established regression model has good fitting degree and reproducibility. Extracted coffee peel total flavonoids has antioxidant capacity. Coffee peel can be developed as a natural source of antioxidants in food industry and pharmacy,etc.
