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二氧化碳超临界萃取山苍子油及其抗氧化效能测定 被引量:7
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作者 李芳 吴健斌 徐会有 《徐州工程学院学报(自然科学版)》 CAS 2012年第2期16-20,共5页
应用二氧化碳超临界萃取法提取山苍子油,以正交设计法考察萃取温度、压力、流量、时间对提取效率的影响,与此同时,以DPPH法测定山苍子油的抗氧化活性,并首次研究了夹带剂使用与不同提取时段对山苍子油提取率及其抗氧化效能的影响.结果表... 应用二氧化碳超临界萃取法提取山苍子油,以正交设计法考察萃取温度、压力、流量、时间对提取效率的影响,与此同时,以DPPH法测定山苍子油的抗氧化活性,并首次研究了夹带剂使用与不同提取时段对山苍子油提取率及其抗氧化效能的影响.结果表明:在50℃、25MPa压力和40L/h流量时,油得率可高达36.7%;单位时间内山苍子油得率随着时间推延呈锐减趋势,第1时段(0~20min)占总出油量的80.86%~97.11%;但从抗氧化效能看,第2时段(20~40min)得到的山苍子油透明度高,抗氧化效果也明显优于前者;在超临界萃取过程中加入夹带剂可以显著提高山苍子油得率及山苍子油的抗氧化活性,以乙酸乙酯为夹带剂,萃取率最高可达45.88%;以甲醇为夹带剂时,山苍子油的抗氧化活性达到最佳值,DPPH法测得IC50仅为0.30g/L,而对照组IC50为7.63g/L. 展开更多
关键词 山苍子 CO2超临界萃取 氧化活性测定 夹带剂
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二次正交旋转超声制备黄芪多糖及其抗氧化性分析 被引量:3
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作者 宋照风 周子凡 +1 位作者 朱峰 赵海全 《植物学研究》 2020年第6期521-535,共15页
该文主要研究利用超声辅助来提取黄芪多糖。通过醇沉、旋转蒸发浓缩,获到提纯过后的黄芪多糖粉末。然后再通过苯酚–硫酸法来测定出多糖的含量。以单因素实验的实验结果为基础来设计二次正交旋转试验,从而得出黄芪多糖提取率的最佳工艺... 该文主要研究利用超声辅助来提取黄芪多糖。通过醇沉、旋转蒸发浓缩,获到提纯过后的黄芪多糖粉末。然后再通过苯酚–硫酸法来测定出多糖的含量。以单因素实验的实验结果为基础来设计二次正交旋转试验,从而得出黄芪多糖提取率的最佳工艺条件。即当液料比为1:7,超声时间为15 min,水浴时间为50 min,水浴温度为70℃时,提取率靠近最佳值为2.19%。并且通过对黄芪多糖进行红外光谱解析,可以证实实验制备所获得的样品是多糖。然后对该实验制备出来的黄芪多糖进行抗氧化性测定。通过羟基自由基清除作用来测定其抗氧化性的能力大小。运用了芬顿法和水杨酸法两种方法,测定出当黄芪多糖的浓度在1 mg∙mL−1时,自由基的清除率分别为15.58%和33.2%。从而证明了黄芪多糖具有良好的抗氧化能力。 展开更多
关键词 黄芪多糖 超声提取 二次正交旋转 抗氧化测定 羟基自由基的清除
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以细胞模型评价乳酸菌无细胞提取物的抗氧化活性 被引量:3
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作者 邢家溧 王刚 +3 位作者 印伯星 房东升 张灏 陈卫 《中国食品学报》 EI CAS CSCD 北大核心 2017年第7期208-213,共6页
目的:利用细胞内抗氧化活性测定方法(CAA)检测乳酸菌无细胞提取物的抗氧化能力及其对肝癌细胞的毒害作用,在细胞水平对乳酸菌无细胞提取物的功能进行评价分析。方法:利用Hep G2细胞构建测定乳酸菌无细胞提取物抗氧化能力的细胞模型,对来... 目的:利用细胞内抗氧化活性测定方法(CAA)检测乳酸菌无细胞提取物的抗氧化能力及其对肝癌细胞的毒害作用,在细胞水平对乳酸菌无细胞提取物的功能进行评价分析。方法:利用Hep G2细胞构建测定乳酸菌无细胞提取物抗氧化能力的细胞模型,对来自4个种的13株乳酸菌的无细胞提取物进行细胞内抗氧化活性以及细胞毒性测定。结果:乳酸菌无细胞提取物抗氧化活性显著高于MRS(P<0.05),其抗氧化活性存在显著的种间与种内差异(P<0.05),嗜酸乳杆菌CCFM8的细胞内抗氧化活性最强,显著高于阳性对照菌株鼠李糖乳杆菌(LGG,P<0.05)。在试验浓度范围,未检测到乳酸菌无细胞提取物对Hep G2细胞具有毒性。结论 :CAA方法能够反映抗氧化物在细胞水平的抗氧化活性,能够对乳酸菌无细胞提取物在细胞水平的抗氧化活性进行定量。该方法在测定乳酸菌相关抗氧化活性方面具有良好的应用前景。 展开更多
关键词 乳酸菌 无细胞提取物 氧化 细胞内氧化活性测定方法
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蓝莓花青素提取纯化、组成成分及其生物活性研究进展 被引量:12
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作者 冯贵涛 彭黔荣 +2 位作者 杨敏 马义虔 吴艾璟 《中国调味品》 CAS 北大核心 2016年第4期146-152,共7页
蓝莓花青素具有降血糖、抗炎、抗癌细胞增殖等多种生物活性。综述了近年来国内外蓝莓花青素提取纯化研究、蓝莓花青素组成成分及其生物活性研究进展,介绍了蓝莓果醋最新研究及抗氧化活性测定的新方法。
关键词 蓝莓花青素 果醋 氧化活性测定 生理活性 提取 纯化
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Determination of the Antioxidant Capacity of Different Types of Bread and Flour Using a Superoxide Dismutase Biosensor 被引量:1
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《Journal of Chemistry and Chemical Engineering》 2012年第3期199-208,共10页
The aim was to experimentally evaluate the antioxidant capacity of different types of bread and of the relative flour used for bread production utilizing a superoxide dismutase (SOD) biosensor recently developed by ... The aim was to experimentally evaluate the antioxidant capacity of different types of bread and of the relative flour used for bread production utilizing a superoxide dismutase (SOD) biosensor recently developed by the present authors. Measurements were carried out by comparing the biosensor response to the concentration of superoxide radical produced in solution using a xanthine/xanthine oxidase system in the presence and in the absence of the antioxidant sample considered, respectively. Precision of antioxidant capacity measures for crust and crumb of the different breads was found to be good (RS D% ≤ 8%) and acceptable for the watery suspension and filtrate of the different flours studied (RSD% ≤ 12%). The obtained results indicated that general flours show higher antioxidant capacity values than the corresponding breads and that crusts show always an antioxidant capacity definitely larger than the crumb. Lastly, the antioxidant capacity values were compared with those of almond, red pepper and strawberry, three foods containing powerful natural antioxidants. 展开更多
关键词 BREAD FLOUR antioxidant capacity superoxide dismutase biosensor.
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Determination of the Antioxidant, Phytochemical and Antibacterial Profiles of Flowers from Selected Ornamental Plants in Nueva Vizcaya, Philippines
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作者 Melfei Estrada Bungihan Claribel Asuncion Matias 《Journal of Agricultural Science and Technology(B)》 2013年第12期833-841,共9页
With the increasing interest on natural products discovery, utilization of plant parts which are commonly disregarded is another breakthrough. This study sought to determine the secondary metabolites present, phenolic... With the increasing interest on natural products discovery, utilization of plant parts which are commonly disregarded is another breakthrough. This study sought to determine the secondary metabolites present, phenolic contents, radical scavenging activities and antibacterial properties of 10 selected ornamental flowers which were Adenium obesum, Allamanda cathartica, Bougainvillea glabra, Catharanthus roseus, Caesalpinia pulcherrima, Heliconia subulata, Ixora coccinea, Mussaenda philippica, Tecoma stans and Torenia fournieri, from Nueva Vizcaya, Philippines. The ethanolic crude extracts were subjected to thin layer chromatography (TLC) phytochemical screening. Total phenolics expressed as mg AAE/g sample were determined through Folin-Ciocalteu method. Radical scavenging activities were measured using DPPH assay. Antibacterial activities were assessed through TLC bioautography. To quantify bacterial susceptibility of C. pulcherrima, MIC and MBC were employed in the ethyl acetate sub-fraction. TLC showed different types of phenolics, alkaloids, essential oils and terpenes. T. fournieri showed the highest total phenolics with 155 mg AAE/g while H. subulatahad showed the lowest with 3.50 mg AAE/g. Measurement of IC59 showed that H. subulata had the highest antioxidant activity followed by T. fournieri with 303 ppm and 320 ppm, respectively. H. subulata having the least amount of total phenolics had greatest radical scavenging activity. This indicates that other than phenolics, other metabolites can pose great antioxidant activities. The antibacterial testing showed that M. philippica, 1. coccinea, 1-1. subulata, C. pulcherrima and A. cathartica were bioactive against Staphylococcus aureus and Escherichia coll. MIC and MBC of C. pulcherrima ethyl acetate sub-fraction is within the range of 2.5-10 mg/mL. 展开更多
关键词 PHYTOCHEMICAL phenolics ANTIOXIDANTS ANTIBACTERIAL ornamental flowers.
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Synthesis of the dl-ξ-Thiotocopherol: Newest Derivative of the dl-a-Tocopherol
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作者 Tuncer Mutlu Ibrahim Erol +1 位作者 Nevin Mutlu Levent Ozcan 《Journal of Chemistry and Chemical Engineering》 2012年第1期90-95,共6页
Tocopherol is the most active vitamin and natural antioxidant existing in the nature known as vitamin E. Lacking of this vitamin makes drastic exchanges on the health of the living organisms. Their active chemical for... Tocopherol is the most active vitamin and natural antioxidant existing in the nature known as vitamin E. Lacking of this vitamin makes drastic exchanges on the health of the living organisms. Their active chemical form is l-α-tocopherol substance. In this article, α-thiotocopherol a tocopherol derivative was synthesized via a precursor like dl-α-tocopherol, which has better antioxidant than natural α-tocopherol. And the last compound after separation and purification via TLC and PC procedures was analyzed by FTIR, GC-MS and elemental analysis, oxidative stability is tested with TGA method in air showing roughly antioxidant effect. Another approach is measurment of redox potential against a reference electrode under inert nitrogen atmosphere. 展开更多
关键词 TOCOPHEROL PHENOLS substitute phenols thiotocopherol redox potential thermal and oxidative stability.
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Research on Fuzi based on animal thermotropism behavior to discover if it has fewer "hot" characteristics without Ganjiang 被引量:4
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作者 孙志勇 赵艳玲 +6 位作者 王伽伯 张琳 魏思思 江凤娟 贾雷 程丹红 肖小河 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2012年第2期208-214,共7页
OBJECTIVE:To investigate whether Fuzi(Radix Aconiti Praeparata) has fewer "hot" characteristics when administered without Ganjiang(Rhizoma Zingiberis).METHODS:Differences in the thermotropism behaviors of mi... OBJECTIVE:To investigate whether Fuzi(Radix Aconiti Praeparata) has fewer "hot" characteristics when administered without Ganjiang(Rhizoma Zingiberis).METHODS:Differences in the thermotropism behaviors of mice treated either with Fuzi(Radix Aconiti Praeparata),Ganjiang(Rhizoma Zingiberis) or the combination of the two given intragastrically were investigated using the Animal Thermotropism Behavior Surveillance System.The water intake volume,oxygen consumption volume,adenosine triphosphatase(ATPase) activity,total antioxidant capacity(T-AOC) and total superoxide dismutase(T-SOD) activity were determined during the investigation.RESULTS:When Fuzi and Ganjiang were administered together,the rate at which mice remained on a warm plate("remaining rate") and the times and distances of their movement were all significantly reduced(P<0.05).Compared with the Normal group,the reduction was 55.1%,48.3% and 44.8%,while compared with the Fuzi group,the reduction was 57.6%,34.3% and 36.0%,indicating that "cold" tropism was significantly increased.Compared with the Normal and Fuzi groups,the ATPase activity and the respiratory oxygen consumption volume of the Fuzi + Ganjiang group were significantly increased(P<0.05),suggesting an improvement in energy metabolism and showing a "hot" characteristic when Fuzi and Ganjiang are present together.Additionally,the T-AOC and T-SOD activity were significantly enhanced(P<0.05).CONCLUSION:The behavior of mice tending toward "cold" tropism can be regarded as a quantitative reflection of Fuzi having fewer characteristics consistent w ith a "hot" nature when not used with Ganjiang,the functional mechanism of which may be a change in the ATPase activity in liver tissue. 展开更多
关键词 Animal thermotropic behavior Objectivity Cold/Hot tropism Fuzi(Radix Aconiti Praeparata) Ganjiang(Rhizoma Zingiberis)
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