摘 要:本论文用乙醇和水作为提取剂,用超声作为辅助提取方法对乙酸乙酯、丙酮提取向日葵后的残渣依次进行提取。采用高效液相色谱法和气相色谱-质谱法分析对提取液的化学成分进行检测,用紫外/可见分光光度计测定提取液中的黄酮和总酚含量,并对其用超氧负离子自由基、DPPH自由基和羟基自由基清除法进行抗氧化活性的试验。得到分析结果为:液相色谱测定得到乙醇提取液具有16个峰,在3.682min处有最大峰,其相对峰面积为31.8%;水提取液具有10个峰,在1.193min处有最大峰,其相对峰面积为32.3%;气质联用测定乙醇提取液主要成分有13种,是2,3-二氢-3,5-二羟基-6-甲基-4H-吡喃-4-酮和5-(羟甲基)-2-呋喃甲醛,水提取液主要成分有10种,是2,3-二氢-3,5-二羟基-6-甲基-4H-吡喃-4-酮和5-(羟甲基)-2-呋喃甲醛。以芦丁和没食子酸分别作为黄酮和总酚含量测定标准,两提取液的黄酮和总酚含量分别为乙醇提取液3.45±0.01mg/g(相当于1g原材料,下同)和0.512±0.003mg/g;水提取液2.93±0.05mg/g和0.293±0.003mg/g。乙醇提取液对O2-·,DPPH·, ·OH自由基清除率IC50值为82.0 mg/mL,3.93 mg/mL,1267.6mg/mL。水提取液对O2-·,DPPH·,·OH自由基清除率IC50值为145.6mg/mL,3.63 mg/mL,2262.2mg/mL。以上结果标明,向日葵盘中包含有抗氧化活性的物质,乙醇和水可以作为其提取剂,乙醇提取液抗氧化活性高于水提取物。60902
毕业论文关键词:向日葵,气质联用,紫外/可见分光光度法,黄酮,总酚,抗氧化活性
Abstract: In this paper, two extracts were extracted from the sunflower plate residue after using acetone extract by using the ultrasonic assisted ethanol and water extraction method sequentially. The components of two extracts, that are ethanol extract of sunflower plate(ES) and water extract of sunflower disc(WS), were analyzed by high performance liquid chromatography(HPLC) and gas chromatography-mass spectrometry(GC-MS).The contents of flavonoids and polyphenols of ES and WS were determined by UV/Visible spectrophotometer, and their antioxidant activity were valuated by the O2-·,1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and OH¬¬·test. Results showed, the 16 peaks were determinated in ES and 10 peaks in WS by HPLC. The retention and relative peak of maximum peak were 3.682min and 31.8 % in ES and were 1.193min and 32.3% in WS. The results of GC-MS analysis showed that there were 13 kinds of main chemical composition of ES, they were C6H8O4, C6H6O3,and there were 10 kinds of main chemical composition of WS, they were C6H6O3,C6H8O4. Using rutin and gallic acid as comparison samples, the content of flavonoids and total phenols of ES and WS were 3.45±0.014mg/g(equivalently 1 g of raw materials, the same below), 0.512±0.003 mg/g and 2.93±0.049mg/g,0.293±0.003mg/g, respectively. The contents of total phenols in ES and WS were, respectively. The IC50 value of ES were serially 82.0 mg/mL,3.93 mg/mL,1267.6mg/mL for O2-·,DPPH and OH¬¬-. The IC50 value of WS were serially 145.6 mg/mL,3.63 mg/mL,2262.2mg/mL. The above results showed that antioxidant properties of ES was better than WS, ethanol and water both can be used as extracting agent to extract the flavonoids and total phenols from sunflower plate, and ethanol has higher extraction efficiency.
Keywords: Sunflower, HPLC, GC-MS, Flavonoids, Total phenols, Antioxidant activity
1. 引言 4
2. 实验部分 5
2.1 材料、仪器与试剂 5
2.2 原料的提取 5
2.3 提取物成分分析方法 5