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目的 评价鼠尾藻和海黍子两种褐藻中高相对分子质量褐藻多酚的抗氧化活性。方法 分别利用 3种体系 ,通过对羟自由基 (· OH)、超氧阴离子 ( O÷2 )和 1,1-二苯基 - 2 -苦味肼基自由基 ( DPPH· )清除效率来评价其抗氧化活性。结果 两种褐藻中高相对分子质量褐藻多酚对· OH、O÷2 和 DPPH·均有很高的清除效率 ,且效果相近。结论 鼠尾藻和海黍子两种褐藻中高相对分子质量褐藻多酚具有较强的抗氧化活性 ,是一类潜在的海洋生物天然抗氧化剂。 相似文献
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鼠尾藻多酚的抗凝血活性研究 总被引:7,自引:0,他引:7
目的探讨鼠尾藻多酚STP-1和STP-2的抗凝血活性。方法体内实验分别以毛细管法、剪尾法测定鼠尾藻多酚对小鼠凝血时间、出血时间的影响;体外实验分别测定鼠尾藻多酚对新西兰兔血浆活化部分凝血活酶时间、血浆凝血酶原时间、血浆凝血酶时间的影响。结果鼠尾藻多酚STP-1在体内、体外均有显著的抗凝血作用,而且中剂量组(1.0mg/mL)抗凝血活性最佳。结论鼠尾藻多酚STP-1在体内、外均有抗凝血活性。 相似文献
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广藿香与土藿香的DNA序列分析及其分子鉴别 总被引:7,自引:0,他引:7
目前市场上藿香类商品药材有两种 ,一种为唇形科刺蕊草属 (Pogostemon)植物广藿香Pogostemoncablin (Blanco)Benth.的干燥地上部分 ,主产广东、海南 ,习称“广藿香”,均为栽培品 ,有芳香化浊、开胃止呕、发表解暑的功效 ,是中成药“藿香正气水”的主要原料。据我们分析广州市郊黄村产“石牌广藿香”药材茎枝挥发油成分 ,其中 71 %为广藿香酮(pogostone) [1 ] ;另一种来源于同科另一属 ,即藿香属(Agastache)植物藿香Agastacherugosa (Fisch.etMey.)O .K… 相似文献
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目的建立同时测定繁枝补血草中槲皮苷和槲皮素含量的HPLC法。方法采用Agilent C18色谱柱(250mm×4.6mm,5.0μm);流动相为甲醇-4mL·L-1磷酸水溶液(50∶50);流速为1.0mL·min-1;检测波长为360nm;柱温为25℃;进样量为10μL。用外标法计算其含量。结果槲皮苷质量浓度在4.912~98.24μg·mL-1范围内与峰面积有良好的线性关系,回归方程y=30.434x-11.864(r=0.999 6);槲皮素质量浓度在12.833~102.667μg·mL-1范围内与峰面积有良好的线性关系,回归方程y=43.358x-45.586(r=0.999 7)。槲皮苷的平均回收率为100.73%,RSD值为1.82%(n=6);槲皮素的平均回收率为100.47%,RSD值为1.35%(n=6)。结论该方法操作简便、快速、准确、误差小、重复性好,可作为繁枝补血草中槲皮苷和槲皮素的定量分析方法。 相似文献
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Shih-Chieh Lee Chia-Hsiang Wang Cheng-En Yen Chieh Chang 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2017,25(2):260
The major aim of made tea identification is to identify the variety and provenance of the tea plant. The present experiment used 113 tea plants [Camellia sinensis (L.) O. Kuntze] housed at the Tea Research and Extension Substation, from which 113 internal transcribed spacer 2 (ITS2) fragments, 104 trnL intron, and 98 trnL-trnF intergenic sequence region DNA sequences were successfully sequenced. The similarity of the ITS2 nucleotide sequences between tea plants housed at the Tea Research and Extension Substation was 0.379–0.994. In this polymerase chain reaction-amplified noncoding region, no varieties possessed identical sequences. Compared with the trnL intron and trnL-trnF intergenic sequence fragments of chloroplast cpDNA, the proportion of ITS2 nucleotide sequence variation was large and is more suitable for establishing a DNA barcode database to identify tea plant varieties. After establishing the database, 30 imported teas and 35 domestic made teas were used in this model system to explore the feasibility of using ITS2 sequences to identify the varieties and provenances of made teas. A phylogenetic tree was constructed using ITS2 sequences with the unweighted pair group method with arithmetic mean, which indicated that the same variety of tea plant is likely to be successfully categorized into one cluster, but contamination from other tea plants was also detected. This result provides molecular evidence that the similarity between important tea varieties in Taiwan remains high. We suggest a direct, wide collection of made tea and original samples of tea plants to establish an ITS2 sequence molecular barcode identification database to identify the varieties and provenances of tea plants. The DNA barcode comparison method can satisfy the need for a rapid, low-cost, frontline differentiation of the large amount of made teas from Taiwan and abroad, and can provide molecular evidence of their varieties and provenances. 相似文献
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目的 比较氯硝柳胺(niclosamide)与杀虫丁[(dimethylamine)trithacyclohexane hydrochloride]、83051(N-pyrib-ine-3-N′-phenyl ureahydrochlorate)、茶树籽[Seed of Camellia sinensis(L)O.Kuntze]配伍的杀螺效果。方法 采用实验室浸杀方法观察氯硝柳胺三种配伍剂的杀螺效果。结果 氯硝柳胺0.2mg/L分别与杀虫丁0.1mg/L、83051 4mg/L和茶树籽10mg/L配伍,其浸杀钉螺LC90分别为0.198mg/L,0.175mg/L和0.151mg/L。结论 氯硝柳胺与杀虫丁配伍剂浸杀钉螺效果较好,氯硝柳胺与83051配伍剂适宜水产经济区使用,氯硝柳胺与茶树籽配伍剂能降低灭螺成本。 相似文献
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Estela I. Guerrero Juan A. Morán-Pinzón José L. López-Pérez Dionisio Olmedo Mahabir P. Gupta 《Journal of ethnopharmacology》2009
Ethnopharmacological relevance
Dimerocostus strobilaceus is used by the Kuna Indians of Panama for the treatment of hypertension and other cardiovascular diseases.Aim of the study
We investigated the vascular effects of acid and neutral fractions obtained from methanol and dichloromethane extracts of Dimerocostus strobilaceus.Materials and methods
The acid and neutral methanol fractions (A-MeOH and N-MeOH) or acid and neutral dichlorometanic fractions (A-DCM and N-DCM) were tested using isolated rat aortic rings with or without endothelium pre-contracted by phenylephrine. We examined the ability of these different fractions at different concentrations to modify vascular responses induced by angiotensin II using endothelium-denuded aortic rings from Spontaneously Hypertensive Rats (SHR).Results
In aortic rings with intact endothelium A-MeOH, N-MeOH and A-DCM fractions produced a concentration-dependent vasorelaxation (62.4 ± 5.2, 64.5 ± 5.0 and 63.7 ± 5.0%, respectively), whereas the N-DCM fraction did not produce any vasorelaxant effect. Maximal relaxation evocated by vasoactive fractions was substantially inhibited on aortic rings without endothelium.Our study demonstrates that A-MeOH, N-MeOH, A-DCM and N-DCM significantly reduce contractile responses induced by angiotensin-II on aortic rings.Conclusions
Our findings may contribute to a better understanding of the potential link between vascular properties observed with Dimerocostus strobilaceus and their ethnobotanical use. 相似文献9.
广防风中苯乙醇类化学成分研究 总被引:1,自引:1,他引:0
目的研究广防风Anisomeles indica全草的化学成分。方法采用硅胶、Sephadex LH-20和ODS柱色谱进行分离和纯化,通过理化性质和波谱数据确定化合物的结构。结果从广防风全草的乙醇提取物中提取分离得到10个化合物,其中7个为苯乙醇类化合物:广防风苷A(1)、圆齿列当苷(2)、毛蕊花糖苷(3)、肉苁蓉苷D(4)、3′-O-methyl isocrenatoside(5)、isocrenatoside(6)、山橘脂酸(7);3个为酚酸类化合物:香草酸(8)、咖啡酸(9)、阿魏酸(10)。结论化合物4~7为首次从广防风属植物中分离得到。 相似文献
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目的 优化珐菲亚组织培养快速繁殖技术。方法 分别以MS和1/2MS为基本培养基,采用正交设计研究植物生长调节剂多因素组合(6-BA、NAA、IBA和IAA)对珐菲亚继代增殖和诱导生根的影响。结果 MS+6-BA 1.5 mg/L+NAA 0.1 mg/L+IBA 0.2 mg/L利于丛生芽继代增殖,30 d繁殖系数6.0以上;1/2 MS+NAA 1.0 mg/L+IBA 0.2 mg/L适于诱导生根获得再生植株,生根率100%;生根苗移栽于排水良好的沙床上,成活率98%。结论 本实验为保护珐菲亚的野生资源,发展人工栽培和探讨育种新途径奠定基础。 相似文献