松茸多糖超声提取物抗氧化活性研究

利用超声波辅助水提及醇沉法从松茸中提取可溶性多糖,多糖提取率达到5.10％,提取物中多糖含量为54.32％.研究了松茸多糖提取物对Fenton反应产生羟基自由基、光照核黄素产生超氧阴离子自由基的清除作用及对羟基自由基诱发卵磷脂脂质过氧化损伤的抑制作用.结果表明,松茸多糖具有良好的抗氧化活性,与茶多酚相近.     

西藏松茸多糖的提取及其单糖组成研究

采用正交实验优化西藏松茸多糖提取工艺条件,并应用气相色谱法对松茸多糖的单糖组成进行分析.确定西藏松茸多糖最佳提取条件为:提取时间4 h、提取温度80℃、料水比1:10、醇析浓度85%,此条件下粗多糖得率为8.98%.色谱分析发现,该多糖是由7种单糖组成的杂多糖.     

薤白多糖的提取及体外抗氧化活性研究

用热水浸提法提取薤白中的生物多糖,采用响应面法对提取条件进行优化,并研究了薤白多糖的体外抗氧化活性。结果表明,最佳提取条件为:提取温度72℃,提取时间1.5 h,液料比20∶1 m L/g,薤白多糖提取率(5.26±0.014)%。薤白多糖具有一定的体外抗氧化能力,但活性低于同浓度的Vc,其中薤白多糖对羟基自由基的清除能力相对较强,IC50值为1 591.7μg/m L;对超氧阴离子自由基的清除能力及对Fe3+的还原能力较弱。     

石楠藤多糖的提取及其抗氧化活性研究

目的:通过正交试验优化石楠藤多糖提取工艺,考察石楠藤多糖清除DPPH自由基的能力.方法:考察提取温度、提取时间、料液比和醇沉体积分数对多糖提取率的影响,寻找最优提取方案;采用DPPH法研究石楠藤多糖的抗氧化能力.结果:石楠藤多糖最佳提取工艺为提取温度80℃、提取时间70 min、料液比1:50(g:mL)、醇沉体积分数...     

松茸多糖的提取精制工艺及其美白功效验证

以松茸为研究对象,通过正交试验法,探究洗脱剂浓度、上样量、径高比对松茸多糖精制工艺的影响,以优化松茸多糖的动态洗脱条件,并将得到的松茸粗提物A1及精制物A2～A4,进行小鼠黑色素瘤细胞（B16）存活率、黑色素合成抑制以及酪氨酸酶活性抑制试验,来验证松茸的美白功效。结果显示：松茸多糖最佳精制工艺为洗脱剂体积分数40%乙醇,上样量30 mg/g（多糖/树脂）,径高比1∶8,在此工艺下松茸多糖的含量最高可达33%(A3组分)。松茸多糖粗提物A1及精制物A2～A4的美白功效试验表明它们都有良好的美白作用,美白效果为A3≥A4> A1> A2。     

猪毛菜多糖的提取及抗氧化活性的研究

猪毛菜分布广泛,含有丰富的多糖成分。本实验采用微波辅助的方法从干燥的猪毛菜中提取猪毛菜多糖,利用单因素和正交试验的方法探究优化猪毛菜多糖的最佳提取工艺,并采用FRAP法研究猪毛菜的体外抗氧化能力。实验结果：最佳提取工艺条件为料液比1︰30(g︰m L^-1)、微波功率640 W、微波时间90 s、提取温度60℃,提取率为2.52%;研究结果表明猪毛菜多糖具有一定的抗氧化能力。     

杠板归多糖提取工艺优化及其体外抗氧化活性研究

采用超声法提取杠板归多糖,用苯酚-硫酸法在490 nm处测定多糖含量,通过正交试验对提取工艺进行优化。以维生素C作为对照组,考察杠板归多糖对DPPH和ABTS~+的清除作用。杠板归多糖的提取工艺条件:温度为100℃,时间为50 min,超声功率为70 W,料液比为1:15 g/mL,此条件下多糖含量为39.84 mg/g。杠板归多糖对DPPH和ABTS~+的清除能力较强,IC_(50)值分别为46.39、61.12μg/mL。超声法提取的最佳工艺科学稳定,杠板归多糖具有良好的抗氧化活性。     

黄秋葵多糖的超声法提取及体外抗氧化活性研究

采用超声提取黄秋葵多糖的最佳提取工艺为:液料比45∶1 mL/g,超声时间18 min,提取温度62℃,超声功率395 W.在此条件下,黄秋葵多糖的提取率(6.94±0.0624)％.黄秋葵多糖具有一定的体外抗氧化能力,清除超氧阴离子自由基的IC50值为2690.8 μg/mL,清除羟基自由基的IC50值为1999.8...     

黄秋葵多糖的超声法提取及体外抗氧化活性研究

采用超声提取黄秋葵多糖的最佳提取工艺为:液料比45∶1 mL/g,超声时间18 min,提取温度62℃,超声功率395 W。在此条件下,黄秋葵多糖的提取率(6.94±0.062 4)%。黄秋葵多糖具有一定的体外抗氧化能力,清除超氧阴离子自由基的IC_(50)值为2 690.8μg/mL,清除羟基自由基的IC_(50)值为1 999.8μg/mL,对Fe⁽³⁺⁾有较好的还原能力。     

干巴菌多糖提取工艺优化及抗氧化活性的研究

以产于云南曲靖的干巴菌为原料,以多糖提取率为评价指标,采用单因素实验及正交实验优化干巴菌多糖的提取工艺,通过测定干巴菌多糖对DPPH自由基及羟基自由基的清除率来评价其抗氧化活性。结果表明,干巴菌多糖的最佳提取工艺为:提取温度70℃、提取时间2.5 h、料液比1∶15(g∶mL),在此条件下,多糖提取率达到10.08%;当干巴菌多糖浓度为5 mg·mL~(-1)时,其对DPPH自由基的清除率为86.99%,对羟基自由基的清除率为87.46%,有较好的抗氧化作用。     

Comparison of Antioxidant Activity of Ethanolic Extracts of Propolis Obtained by Different Extraction Methods

The antioxidant activities of the ethanolic extracts of propolis obtained by different extraction methods (high hydrostatic pressure extraction, leaching at room temperature and heat reflux extraction) were investigated in relationship to their total polyphenol and flavonoid contents by two different assays, namely, the β‐carotene bleaching and 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) free radical scavenging assay systems. The results showed that the ethanolic extracts of propolis obtained by high hydrostatic pressure extraction and leaching at room temperature had relatively strong antioxidant activities, which may be correlated with the total polyphenol and flavonoid contents. Antioxidant activities of ethanolic extracts of propolis obtained by high hydrostatic pressure extraction were the same as those of ethanolic extracts of propolis obtained by leaching at room temperature. Leaching at room temperature usually needs a few days, and can take even more than 7 d, while high hydrostatic pressure extraction needs only 1 min. These findings further illustrate that the high hydrostatic pressure extraction has a bright prospect for extracting flavonoids from propolis.     

不同苦瓜多糖的体外抗氧化活性研究

从总还原能力、体外清除羟自由基能力、体外清除超氧阴离子自由基能力、体外清除1,1-二苯基-2-苦苯肼自由基(DPPH.)能力、对Fe2+诱发的脂质过氧化反应的抑制作用这五个方面对6种苦瓜多糖(即:苦瓜粗多糖、0.1mol/L NaC l溶液洗脱苦瓜多糖、0.3 mol/L NaC l溶液洗脱苦瓜多糖、硫酸化的苦瓜多糖)的体外抗氧化活性。结果表明,6种苦瓜多糖均有一定的抗氧化活性,并随着浓度的增加,抗氧化活性增强。其中苦瓜粗多糖MCP的总还原能力、对1,1-二苯基-2-苦苯肼自由基(DPPH.)的清除作用、Fe2+诱发的脂质过氧化反应的抑制作用强于其它五种苦瓜多糖。硫酸化后的苦瓜多糖对羟自由基、超氧阴离子自由基的清除作用较硫酸化前有所提高,并呈量效关系。试验结果表明,苦瓜粗多糖、经分离纯化得到的组分、硫酸化苦瓜多糖均有抗氧化活性。     

Polysaccharides of Salsola passerina: Extraction,Structural Characterization and Antioxidant Activity

The above-ground part of the Salsola passerine was found to contain ~13% (w/w) of polysaccharides extractable with water and aqueous solutions of ammonium oxalate and sodium carbonate. The fractions extracted with aqueous sodium carbonate solutions had the highest yield. The polysaccharides of majority fractions are characterized by similar monosaccharide composition; namely, galacturonic acid and arabinose residues are the principal components of their carbohydrate chains. The present study focused on the determination of antioxidant activity of the extracted polysaccharide fractions and elucidation of the structure of polysaccharides using nuclear magnetic resonance (NMR) spectroscopy. Homogalacturonan (HG), consisting of 1,4-linked residues of α-D-galactopyranosyluronic acid (GalpA), rhamnogalacturonan-I (RG-I), which contains a diglycosyl repeating unit with a strictly alternating sequence of 1,4-linked D-GalpA and 1,2-linked L-rhamnopyranose (Rhap) residues in the backbone, and arabinan, were identified as the structural units of the obtained polysaccharides. HMBC spectra showed that arabinan consisted of alternating regions formed by 3,5-substituted and 1,5-linked arabinofuranose residues, but there was no alternation of these residues in the arabinan structure. Polysaccharide fractions scavenged the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical at 0.2–1.8 mg/mL. The correlation analysis showed that the DPPH scavenging activity of polysaccharide fractions was associated with the content of phenolic compounds (PCs).     

丁香不同提取方法提取物的抗氧化活性

采用微波辅助提取、超声辅助提取和索氏提取3种方法对丁香非挥发性成分进行提取,通过对比单因素实验下不同提取方式得到的总黄酮、总酚含量和抗氧化能力,并结合扫描电镜下丁香粉末的微观结构,选择最佳提取方式;再通过响应面实验优化提取工艺。结果表明,微波辅助提取为最佳提取方式,最优提取工艺条件为微波功率248 W,提取温度52℃,乙醇体积分数72%,提取时间23.5 min,在该条件下总黄酮含量为30.96%±0.44%(309.62±4.41 mg/g),总酚含量70.13%±0.86%(701.34±8.64 mg/g),与预测值相符。DPPH自由基清除能力为99.67%±0.32%、ABTS自由基清除能力为99.81%±0.22%、铁离子还原能力为4.01±0.16 mmol/L、Fe~(2+)螯合能力为30.73%±0.92%、抗脂质过氧化能力为83.44%±1.27%,丁香非挥发性成分提取物具有较好的抗氧化能力。     

Effect of Different Drying Methods on the Microwave Extraction of Phenolic Components and Antioxidant Activity of Highbush Blueberry Leaves

In the last few decades, researchers have found blueberry leaves to be an interesting source of different phenolic compounds, and drying is an important part of their postharvest and sample preparation processes. In the current study, blueberry leaves were dried using microwave-assisted hot air drying or hot air drying alone at 45, 60, and 75°C to 10–15% wet basis. Corresponding drying characteristics were determined by fitting the moisture ratio obtained in each case with eight theoretical and semitheoretical models for hot air and microwave drying stages. It was observed that best fitting drying models for blueberry leaves depended not only on the nature of the biomaterial but also on the method of drying and the temperature of drying. Phenolic content, monomeric anthocyanin content, and the corresponding antioxidant activity in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition activity and ferric reducing ability of plasma (FRAP) activity were evaluated for the leaf extract obtained following microwave extraction of the dried samples obtained using the above-mentioned drying methods and were compared to the corresponding bioactive compositional characteristics of freeze-dried blueberry leaves. It was observed that the freeze-dried sample had the highest content of total phenolics and total monomeric anthocyanins along with high antioxidant activity. Furthermore, extracts obtained from the microwave-dried leaf samples obtained with a drying temperature of 60°C had highest total phenolic content and highest total monomeric anthocyanin content among all other drying methods and the extract had an antioxidant activity similar to the freeze-dried blueberry leaf samples, implying that microwave drying at 60°C is a potential alternative to freeze drying for preservation of the phenolic components and antioxidant activity of dried blueberry leaves.     

正交设计优化龙利叶多糖的超声波提取及体外抗氧化研究

优化超声法提取龙利叶多糖,研究龙利叶多糖的体外抗氧化活性。通过单因素实验和正交设计,研究料液比、超声功率、超声提取温度和超声作用时间对龙利叶多糖提取效果的影响。制备龙利叶多糖,通过对1,1-二苯基-2-三硝基苯肼自由基(DPPH·)、O_2~-的清除测定,评价其体外抗氧化活性。超声提取法的优化工艺条件为:龙利叶干粉1g,蒸馏水100mL,超声功率180W,提取温度60℃,作用时间80min。龙利叶多糖的得率为23.43%。抗氧化性试验数据显示龙利叶多糖对DPPH·和·O_2~-具有较强的清除能力。龙利叶多糖具有较强的抗氧化活性。     

管花肉苁蓉药渣中多糖提取工艺及体外抗氧化活性研究

在单因素实验的基础上,通过正交实验优化了管花肉苁蓉药渣中多糖的提取工艺,并对其体外抗氧化活性进行了初步研究。结果表明,最佳提取工艺条件为:提取温度90℃、料液比1∶50(g∶mL)、提取时间2.0 h,在此条件下,管花肉苁蓉多糖提取率为5.76%;管花肉苁蓉多糖具有较高的抗氧化活性,其对DPPH自由基、羟基自由基具有清除能力,对铜离子有较强的还原能力。该提取方法简便易行,节能环保,适用于管花肉苁蓉多糖的提取。