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1.
目的研究芙蓉菊多糖的体外抗氧化活性。方法采用1,1-二苯基苦基苯肼(DPPH)自由基、还原力、超氧阴离子、羟自由基4种体外抗氧化模型研究芙蓉菊多糖的抗氧化活性,用维生素C作对照。结果芙蓉菊粗多糖对DPPH自由基、还原力、超氧阴离子、羟自由基均有明显的清除能力,其中DPPH、超氧阴离子、羟自由基的EC50值分别为0.273、0.669、0.594mg/mL,对羟自由基清除能力强于维生素C。芙蓉菊多糖对自由基清除率与其质量浓度存在着明显的量效关系。结论芙蓉菊多糖具有良好的体外抗氧化活性,作为天然抗氧化剂和自由基清除剂有进一步研究的价值。  相似文献   

2.
目的:研究马齿苋全草提取物体外的抗氧化活性。方法:选取1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picryl-hydrazine,DPPH)自由基、羟基自由基、超氧阴离子自由基,以及还原能力体系对马齿苋提取物进行抗氧化活性测定。与阳性对照药没食子酸和维生素C作比较。结果:马齿苋提取物清除DPPH自由基、羟基自由基和超氧阴离子自由基的能力在低浓度时弱于阳性对照药没食子酸和维生素C,但随着浓度的增加,其清除活性均明显优于阳性对照药。在0~200μg/ml浓度范围内,马齿苋提取物的还原能力弱于2,6-二叔丁基对甲酚。结论:马齿苋提取物具有较好的清除自由基能力,但还原能力相对较弱。马齿苋可能是有效的外源性天然有机抗氧化剂。  相似文献   

3.
蔓荆子挥发油体外化学模拟抗氧化活性的研究   总被引:1,自引:0,他引:1  
目的:研究蔓荆子挥发油的体外抗氧化活性。方法:应用 Fenton 体系和邻苯三酚自氧化法评价蔓荆子挥发油的体外抗氧化能力,采用多元线性回归对挥发油浓度与抗氧化活性相关性作了分析。结果:蔓荆子挥发油对羟基自由基(—OH)和超氧自由基(O^2-)清除能力与浓度呈明显的量-效关系;挥发油浓度与对羟基自由基(—OH)和超氧自由基(O^2-)清除能力呈正相关。结论:蔓荆子挥发油具有较强的抗氧化能力,是1种天然有效的抗氧化剂。  相似文献   

4.
茶多酚的抗氧化作用及机制   总被引:27,自引:0,他引:27  
茶多酚是茶叶生物活性的主要有效成分,是一种天然抗氧化剂。本文从清除自由基、抑制酯质过氧化、螯合金属离子及增强其他抗氧化剂作用等方面对茶多酚的抗氧化作用研究作一综述。  相似文献   

5.
张培全  谭茵  张超 《中南药学》2012,10(3):171-174
目的 研究菟丝子提取物的体外抗氧化活性.方法 采用热水提取、酶-Sevage法除蛋白、不同比例乙醇分级沉淀等方法获得菟丝子多糖提取物;经95%乙醇回流提取,2乙酸乙酯、正丁醇萃取,得到乙酸乙酯和正丁醇提取物.利用1,1-二苯基-2-苦苯肼自由基(DPPH·)和超氧阴离子自由基(O2-·)分别测定了各组分的抗氧化活性.结果 菟丝子提取物均具有一定的抗氧化活性,且呈显著的量效关系.菟丝子乙酸乙酯、正丁醇提取物清除自由基的能力大于氧化型谷胱甘肽,小于还原型谷胱甘肽;菟丝子多糖清除自由基的能力均小于氧化型谷胱甘肽,其中90%醇沉多糖清除自由基的能力较强.结论 菟丝子乙酸乙酯、正丁醇提取物以及90%醇沉多糖是天然抗氧化剂的良好来源,可以进一步分离纯化.  相似文献   

6.
黄彬彬  马健雄 《中国药师》2013,16(7):952-954
目的:研究壮药红鱼眼黄酮类化合物的提取工艺及其抗氧化活性.方法:用乙醇回流提取法通过正交设计试验确定黄酮提取工艺的最佳条件,用氧化法测定其清除超氧自由基和DPPH·自由基的能力.结果:红鱼眼黄酮提取的最佳条件为:8倍量60%乙醇提取3次,每次1 h.所得黄酮在一定浓度范围内具有较强的清除自由基和抗氧化能力.结论:优选的提取工艺效率高,所制备的黄酮有较强的清除超氧自由基和DPPH·自由基活性,具有很好的抗自氧化效果,是一种较好的天然抗氧化剂.  相似文献   

7.
海洋生物抗活性氧资源的研究与开发前景   总被引:2,自引:0,他引:2  
<正> 活性氧自由基对机体产生的危害可以借清除剂进行清除,以缓解乃至制止这种危害。由于机体自身就存在平衡自由基在细胞内水平的天然抗氧化剂,包括大分子的抗氧化酶和小分子的抗氧化剂,故可从动植物、微生物中提取分离。最近的工作报道,已有从天然食物的营养素及中草药有效成份中分离到抗活性氧自由基的物质,如SOD皂甙、黄酮等。现结合海洋生物的抗活性氧资源开发前景作扼要介绍。(一)大分子的自由基清除剂。  相似文献   

8.
目的测定黑果小檗各部位中总黄酮含量并评价其体外抗氧化活性,为有效利用黑果小檗资源提供参考。方法采用紫外分光光度法测定黑果小檗中总黄酮的含量,并通过DPPH、羟自由基和氧自由基清除法评价黑果小檗提取物的抗氧化活性。结果黑果小檗果实中总黄酮含量较高;其次为茎皮及根皮;果实提取液的抗氧化活性较强,茎皮次之。结论黑果小檗提取物具有一定的抗氧化能力,本研究可为天然抗氧化剂的开发提供依据。  相似文献   

9.
天然药物中抗氧化剂的研究进展   总被引:4,自引:0,他引:4  
目的:探讨氧化损伤在癌变中的作用及抗氧化剂清除体内过多的活性氧的作用机制。方法:在介绍抗氧化剂清除体内过多的活性氧的作用机制的基础上,寻找天然药物中可能存在的抗氧化剂,按单体成分分类,进行文献的分类整理。结果:黄酮类、苯酚类、萜类、多糖类及维生素和微量元素硒等都具有较强的抗氧化活性。结论:许多天然来源的抗氧化物质都具有较强的抗癌活性。  相似文献   

10.
目的:从清除1,1-二苯基-2-苦苯肼自由基(DPPH?)、羟自由基(? OH)、超氧阴离子自由基(O2?-)3个方面,研究茉莉花挥发油清除自由基活性。方法采用水蒸气蒸馏法提取茉莉花挥发油,从其清除DPPH?、? OH和O2?-能力3个方面进行考察,并以常用抗氧化剂L-抗坏血酸为对照作比较,通过计算半数抑制浓度( IC50)评价茉莉花挥发油清除,在供试质量浓度范围内,呈一定量效关系,其 IC50分别为153.548μg?mL -1、56.481μg? mL -1和133.586μg? mL -1。结论茉莉花挥发油具有良好的清除自由基活性,是一种新型天然抗氧化物质来源。  相似文献   

11.
生物碱是一类重要的天然物质,多具有结构新颖、活性显著等特点,一直是新药研发的热点。本文针对2015-2020年期间新发现的来源于海洋天然产物的生物碱进行了综述,主要从抑菌、抗癌、抗氧化、抗炎、抗病毒等药理活性方面进行阐述,以期为开发新的海洋生物碱药物提供理论依据。  相似文献   

12.
植物雌激素是指具有类似动物雌激素结构或活性的植物成分,其对健康的重要作用受到广泛关注,中药含有多种成分具有植物雌激素作用.皂苷是一类重要的天然产物,具有抗肿瘤、抗氧化、抗炎和免疫调节、抗骨质疏松、抗病毒、心血管保护、神经保护、延缓衰老、调节糖脂代谢等作用,临床上对于子宫内膜异位症、乳腺癌、前列腺癌、骨质疏松、心血管疾病...  相似文献   

13.
The chemical diversity of plant-derived natural products allows them to function in a multitude of ways including flavor enhancers, agricultural chemicals, and importantly, human medicinals. Supply of pharmaceutically active natural products is often a challenge due to the slow growing nature of some species, low yields found in nature, and unpredictable variability in accumulation. Several production options are available including natural harvestation, total chemical synthesis, semisynthesis from isolated precursors, and expression of plant pathways in microbial systems. However, for some medicinal natural products, such as the anticancer agent paclitaxel, where low yields in nature, chemical complexity and lack of knowledge of the complete biosynthetic pathway, preclude many of these options, plant cell culture technology is an attractive alternative for supply. Plant cell suspension cultures are amenable to scale-up, environmental optimization, and metabolic engineering. This review focuses on some of the key challenges in utilizing and commercializing plant cell culture suspension technology, with a focus on pharmaceutically active natural products. Recent research has been directed toward application of traditional strategies such as reactor design, cell immobilization, and enzyme elicitation as well as emerging strategies such as characterizing cellular heterogeneity and variability through flow cytometric techniques, metabolic engineering, and system-wide analysis.  相似文献   

14.
张爽  刘新泳 《药学进展》2012,36(6):241-251
查耳酮类化合物广泛存在于天然植物中,具有抗癌、抗炎、抗氧化等多种药理活性。近年来,通过对大量具有查耳酮骨架的新型化合物的合成,查耳酮衍生物的生物活性也得到了深入研究。综述查耳酮衍生物的生物活性、结构修饰及构效关系的最新研究进展。  相似文献   

15.
1. There has been increasing awareness and use of natural preparations for health purposes by consumers. 2. However, recent studies have repeatedly shown that many natural products marketed as nutraceuticals or health food do not deliver the health benefit as claimed and are inconsistent from batch to batch. 3. The present paper describes the scientific rationale of such inconsistency and uses an antihypertensive preparation as an example to demonstrate the significant value of natural products if developed scientifically and properly.  相似文献   

16.
Medicinal plants play an important role in providing affordable healthcare, making them valuable natural products. The growing demand for plant-derived bioactive compounds motivates researchers to seek the best approaches for molecule extraction in terms of quality, yield, processing cost, and environmental protection. Populus nigra L. (PN) is a Salicaceae-family poplar tree, with high therapeutic potential due to the anti-oxidant, anti-inflammatory, hepatoprotective, hypouricemic, anti-tumor, and anti-microbial properties of its various fractions. PN was traditionally used to treat arthritis, rheumatism, liver disorders, and fever. More than 100 molecules have been identified, including phenolic compounds, terpenoids, flavones, flavanones, caffeic/ferulic acids and their derivatives were found in various aerial parts of the plant, as well as nearly 50 phyto-compounds in its essential oil. Furthermore, the benefit of propolis biological activities has brought an increased interest in its chemical composition which was reported to contain different varieties of phenolic compounds with health benefits. This review intends to provide detailed profiling of major molecules identified from PN aerial parts, as well as a comprehensive look at various extraction and characterization methods applicable to PN natural products. Also, bring up to date the existing data on the biological activities and therapeutic uses of Populus nigra L. aerial parts from 1991 to 2021.  相似文献   

17.
近年来有研究显示,含有异戊烯基结构的天然咕吨酮类化合物对多种肿瘤具有显著抑制活性,故而从此类化合物中寻找具有开发价值的抗肿瘤先导化合物,已成为一个研究热点。按来源分别介绍异戊烯基咕吨酮类天然化合物及其抗肿瘤活性研究新进展,并对其中部分化合物的作用机制及构效关系进行了初步探讨。  相似文献   

18.
近年来,艾滋病感染人数急剧增加,已成为威胁人类健康的重大疾病。为了解抗人类免疫缺陷病毒(HIV)药物的研究现状和发展趋势,对Thomson Reuters Integrity数据库中收录的抗HIV药物信息进行统计,从药物发展阶段、药物类型、作用靶点和天然来源类型等方面进行分析。研究发现,抗HIV药物大多处于生物测定阶段,生物制品在药物类型中占绝对优势,作用靶点大多数是针对HIV复制周期中的关键酶,抗HIV药物的天然来源以植物为主,天然产物是未来重要的发展方向。  相似文献   

19.
肖成骞  胡立宏 《药学研究》2016,35(8):436-443
天然产物是现代药物开发中先导结构的重要来源,但是天然活性先导化合物在天然生命体中往往含量微少,这严重限制了其临床前及临床研究,难以满足其后续的市场需求.本文通过具体案例剖析,归纳总结了源于结构复杂的天然产物在药物开发中资源问题的几种有效解决方案:①寻找量丰的核心天然骨架,再经半合成制备;②寻找其量丰的生源合成前体经仿生合成制备;③由量丰天然类似物经化学转化制备;④简化先导结构再全合成制备.希望为解决复杂天然产物药物开发中的资源供应提供借鉴.  相似文献   

20.
Marine pharmacology, the pharmacology of marine natural products, has been for some time more associated with marine natural products chemistry rather than mainstay pharmacology. However, in recent years a renaissance has occurred in this area of research, and has seen the US Food & Drug Administration (FDA) approval in 2004 of Prialt® (ziconotide, ω-conotoxin MVIIA) the synthetic equivalent of a conopeptide found in marine snails, used for the management of severe chronic pain. Furthermore Yondelis® (trabectedin, ET-743) an antitumor agent discovered in a marine colonial tunicate, and now produced synthetically, receiving Orphan Drug designation from the European Commission (EC) and FDA for soft tissue sarcomas and ovarian cancer and its registration in 2007 in the EU for the treatment of soft tissue sarcoma. The approval/marketing of so few marine natural products has come after many years of research primarily by the academic community and the sporadic involvement of major pharmaceutical companies. This commentary, through the opinions provided by several leaders in the marine natural products field, will examine the potential reasons and perceptions from both the academic and pharmaceutical communities regarding the development of marine natural products as viable therapeutic entities.  相似文献   

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