56 resultados para Vitaceae


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Analisou-se os grãos de pólen de 31 espécies brasileiras de Cissus L. (Vitaceae Juss.). Este é o maior gênero da família, com cerca de 350 táxons. Na região neotropical foram localizadas 75 espécies, tendo sua maior representatividade na América do Sul com 48 representantes endêmicos. No Brasil apenas o gênero Cissus ocorre naturalmente em todos os estados e é representado por 48 espécies, podendo ser encontrado em áreas de mata, campos, restingas e cerrados. Neste estudo foram analisados 14 grupos taxonômicos informais com a finalidade de descrever a morfologia polínica e estabelecer se os atributos polínicos seriam úteis à taxonomia do grupo. O material botânico utilizado foi obtido através de exsicatas depositadas nos herbários brasileiros. Os grãos de pólen foram tratados pelo método de acetólise láctica, sendo posteriormente mensurados, descritos, fotomicrografados em microscopia de luz; realizou-se tratamento estatístico (expressos em tabelas). Para análise em microscópio eletrônico de varredura (MEV), as anteras foram rompidas e os grãos de pólen, não acetolisados, espalhados sobre uma fita de carbono. Foram caracterizados quanto à forma, ao tamanho, ao tipo de abertura, à polaridade e a ornamentação da sexina. Os grãos de pólen foram descritos como: médios a grandes, isopolares ou heteropolares, oblato-esferoidais a prolatos, 3-colporados, colpos muito longos ou longos, com margem ornamentada ou não, membrana granulada, presença ou não de opérculo; endoabertura geralmente lalongada, algumas vezes apresentando costa e/ou fastígio; a sexina variou de microrreticulada, perfurada a reticulada; a sexina é geralmente mais espessa que a nexina. Com os resultados construiu-se uma chave polínica na qual foi possível reunir espécies com caracteres semelhantes subordinadas a mais de um Grupo. Com esta pesquisa concluiu-se que os atributos polínicos permitiram a distinção da maior parte dos táxons, exceto quatro, confirmando a heterogeneidade polínica do gênero. Espera-se que este estudo contribua para o melhor conhecimento da taxonomia do gênero e forneça dados para uma filogenia futura.

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Aim of the study: Cissus sicyoides L. is a medicinal plant popularly known in Brazil against various diseases and the research interest in this plant is justifiable because of its potential medicinal value in stomachache and gastric ulcer.Materials and methods: The methanolic extract obtained from the leaves of Cissus sicyoides (Cc) was evaluated for the ability to protect the gastric mucosa against injuries caused by necrotizing agents (0.3 M HCl/60% EtOH, absolute ethanol, piroxicam and pylorus ligature) in rodents. We also evaluated microcirculation, antioxidant action and participation of NO (nitric oxide) and sulfhydryls (SH) groups in the Cc gastroprotective action.Results: Administration of Cc significantly reduced gastric lesions induced by different ulcerogenic agents in rodents. This extract administered by oral route significantly increased gastric volume without exerting antisecretory effect. The Cc effect involved an increase of the defense mechanism of the gastrointestinal mucosa such as NO and SH groups that prevent and attenuate the ulcer process. The Cc also has antioxidant property against oxidative stress but does not modify microcirculation response in gastric mucosa.Conclusions: These results confirmed the traditional use of Cissus sicyoides for the treatment of gastric ulcer. (C) 2008 Elsevier B.V. All rights reserved.

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In South America, the family Vitaceae is represented by 65 species divided into 2 genera: Cissus contains 64 species, whereas Vitis consists of only I species. Recent studies on the Neotropical Cissus reveal that with regard to species delimitation, trichome types and the morphology of fruits and seeds are more important than the traditionally used trichome density and leaf shape. Fifteen provisional species groups are recognized for South America, excluding one species whose grouping is uncertain. Future research in this area should incorporate other data (e.g., anatomical, histological, and molecular) to identify a subgeneric division in Cissus.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Three new species, Cissus nicaraguensis, C. patellicalyx, and Ampelocissus mesoamericana, are described from Nicaragua, Costa Rica, and El Salvador, respectively. Cissus nicaraguensis can be distinguished from all other Neotropical species by the combination of urceolate calyx and simple leaves. Cissus patellicalyx is recognized by its subspherical floral buds, immature fruits minutely tuberculate when dried, and the distinctly raised nerves of the abaxial leaf surface. Ampelocissus mesoamericana is characterized by lenticels, indument, and the obpyriform flower buds.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Background: Mango fruits contain a broad spectrum of phenolic compounds which impart potential health benefits; their biosynthesis is catalysed by enzymes in the phenylpropanoid-flavonoid (PF) pathway. The aim of this study was to reveal the variability in genes involved in the PF pathway in three different mango varieties Mangifera indica L., a member of the family Anacardiaceae: Kensington Pride (KP), Irwin (IW) and Nam Doc Mai (NDM) and to determine associations with gene expression and mango flavonoid profiles. Results: A close evolutionary relationship between mango genes and those from the woody species poplar of the Salicaceae family (Populus trichocarpa) and grape of the Vitaceae family (Vitis vinifera), was revealed through phylogenetic analysis of PF pathway genes. We discovered 145 SNPs in total within coding sequences with an average frequency of one SNP every 316bp. Variety IW had the highest SNP frequency (one SNP every 258bp) while KP and NDM had similar frequencies (one SNP every 369bp and 360bp, respectively). The position in the PF pathway appeared to influence the extent of genetic diversity of the encoded enzymes. The entry point enzymes phenylalanine lyase (PAL), cinnamate 4-mono-oxygenase (C4H) and chalcone synthase (CHS) had low levels of SNP diversity in their coding sequences, whereas anthocyanidin reductase (ANR) showed the highest SNP frequency followed by flavonoid 3'-hydroxylase (F3'H). Quantitative PCR revealed characteristic patterns of gene expression that differed between mango peel and flesh, and between varieties. Conclusions: The combination of mango expressed sequence tags and availability of well-established reference PF biosynthetic genes from other plant species allowed the identification of coding sequences of genes that may lead to the formation of important flavonoid compounds in mango fruits and facilitated characterisation of single nucleotide polymorphisms between varieties. We discovered an association between the extent of sequence variation and position in the pathway for up-stream genes. The high expression of PAL, C4H and CHS genes in mango peel compared to flesh is associated with high amounts of total phenolic contents in peels, which suggest that these genes have an influence on total flavonoid levels in mango fruit peel and flesh. In addition, the particularly high expression levels of ANR in KP and NDM peels compared to IW peel and the significant accumulation of its product epicatechin gallate (ECG) in those extracts reflects the rate-limiting role of ANR on ECG biosynthesis in mango. © 2015 Hoang et al.

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葡萄属(Vitis.L.)植物隶属于葡萄科(Vitaceae),主要分布于北温带,最南可以分布到南美洲的委内瑞拉和亚洲的越南以及印度北部。本文通过对该属分类研究历史的回顾,认为该属存在的问题主要表现在如下几个方面: 1)葡萄属自1753 年由Carl Linne创立以来,虽经planchon于1887年做了修订,但属的范围仍需进一步界定;2)在Planchon之后的100多年中未见有一全面的分类学修订工作,出现在该属的800多个名称需要考证;3)对一些广布种的变异认识不足,导致了大量可疑种。针对这些问题本文进行了如下几个方面的工作: l、形态学:通过大量的野外工作和标本观察,对该属植物的主要性状做了分析,讨论了这些性状状态在葡萄属中的变异规律及演化趋势,将灌木状习性、退化的卷须以及不裂的叶片视为进化的性状。 2、细胞学:利用前人对葡萄属(Vitis.L.)染色体数目的统计及一些杂交实验分析的结果,结合形态学等方面的特征分析,认为在葡萄科,染色体基数X=10为原始的,而x=19则为衍生的。葡萄属的染色体基数xl9(2n=38),多倍体较少见;麝香葡萄属[Muscadinia (Planch.) Sma11]的染色体基数为x=10 (2n=20).与蛇葡萄属、酸蔹藤属和爬山虎属的一致。葡萄属和麝香葡萄属间的杂种是不育的。 3、孢粉学:对葡萄属32种5变种及麝香葡萄属[Muscadinia (Planch.) Sma11]1种的花粉外壁做扫描电镜观察,结果发现花粉外壁雕纹在这两属间和葡萄属内变异较小,对区分属以及属下种上类群意义不大,但对种的鉴别有重要的价值。 4、植物化学:前人对植物化学的工作表明,植物的一些次生代谢产物如类黄酮化合物在葡萄科各类群中的分布规律较好地反映了各类群间的关系。这些结果较好地支持了Planchon对葡萄属范围的界定。 5、山葡萄复合体(V.amurensis complex)包括山葡萄(V.amurensis Rupr.)、燕山葡萄(V.amuresis Rupr. var. dissecta Skvorts.=var.yanshanensisD.Z.Lu et H.P.Liang)、百花山葡萄(V.baihuashanensis M.S.Kang et D.Z.Lu)、复叶葡萄(V.piasezkii Maxim.)、少毛复叶葡萄[V. piasezkii Maxux1.var. pagnuccii (Planch.) Rehd.]共3个种和2个变种,广泛分布于中国北方,形态变异较大。本文对该复合体做了形态分析,并用RAPD (Random Amplified Polymorphic DNAs)分子标记方法分析了这几个类群的关系。综合这些结果,归并了燕山葡萄和百花山葡萄。 在上述工作的基础上,我们得出了如下的结论: l、葡萄属在葡萄科中是一个进化的类群。整理后的葡萄属包括8系62种、l亚种和15变种,其中有2个新系、1个新组合系、2个新变种、1个新组合种和l3个新异名。 2、本文赞同SmaU在1903年作出的分类学处理,把麝香葡萄作为一个独立的属,比葡萄属原始但与葡萄属有着最近的亲缘关系。 3、依据形态特征和APD分析结果把山葡萄复合体的3个种2变种归并为2种l变种,即山葡萄、复叶葡萄和少毛复叶葡萄,认为分子标记技术在分析属内近缘种闻关系上很有价值。 4、葡萄属具有东亚和北美2个现代分布中心,该属可能起源于北美的东部,在晚白垩纪经白令陆桥散布至欧亚大陆。

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地锦(Parthenocissus tricuspidata)为葡萄科(Vitaceae)地锦属(Parthenocissus)多年生大型落叶木质藤本植物,集绿化、环境保护、药用价值为一体,开发利用前景非常广阔。为了进一步有效地利用及增加它的适应性,本论文对地锦的遗传转化及其抑菌活性进行了初步研究。 利用根癌农杆菌(Agrobacterium tumefaciens)介导对地锦进行遗传转化。所转外源目的基因为干旱应答因子结合蛋白DREB基因,克隆自拟南芥,受干旱应答基因启动子rd29Bp驱动。将此基因与pCAMBIA2301重组构建得到植物表达载体p2326。p2326携报告基因b-葡萄糖苷酸酶基因(gus)和选择基因新霉素磷酸转移酶基因(npt II)。然后将p2326导入根癌农杆菌EHA105,对地锦愈伤组织及外植体茎段进行转化。经3-4轮卡那霉素选择培养后,PCR及GUS组织染色验证,表明成功获得了转基因愈伤组织。 对地锦愈伤组织进行耐盐及脯氨酸含量测定。结果表明,转基因愈伤组织与非转基因愈伤组织相比,对高盐的耐受力有较大提高。在250 mM NaC1的继代培养基中,携DREB基因的愈伤组织能够存活20 d以上,而对照在10 d后大多数褐化死亡。高盐胁迫时转基因材料脯氨酸含量高于对照,并能够维持较长时间。 研究还发现,来自室外自然生长的地锦茎、叶,对根癌农杆菌有极强的抑制作用。 因此,对地锦的抑菌作用进行初步研究。 对一年中不同时期(分别采于4月、8月、12月)的地锦茎、叶进行抑菌活性初步研究。结果表明,12月份地锦叶片对所选细菌抑制作用最强。然后对其进行分溶剂萃取。分别用极性递增的有机溶剂依次提取地锦中的有效成分、逐级分离、浓缩干燥,得到石油醚部、乙酸乙酯部、正丁醇部和水部等不同极性溶剂萃取物。选择革兰氏阳性菌和阴性菌共5种对得到的各部分粗提物分别做抑菌实验,表明正丁醇部的抑菌活性最强,水部提取物有一定抑制作用,而石油醚部、乙酸乙酯部没有表现出明显抑菌作用。 地锦正丁醇提取物对大肠杆菌、枯草杆菌、短小芽孢杆菌、农杆菌及酵母菌的最低抑制浓度(MIC)分别为0.25,0.3,0.25,0.3,1g/mL。其抑菌活性随着浓度增加而增强,而且抑菌活性具有较好的热稳定性。 研究发现地锦所产生的抑菌物质不仅对无耐药性的细菌具有抑制作用,而且还对某些耐药性细菌具有抑制作用。目前,细菌对抗生素的耐药性已成为全球关注的问题,寻找新型抗生素已迫在眉捷,地锦抑菌物质的研究为新抗菌药物的研制开发提供了新思路。 上述研究结果,为地锦的遗传改良及开发利用打下基础。

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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There is abundant evidence that reactive oxygen species are implicated in several physiological and pathological processes. To protect biological targets from oxidative damage. antioxidants must react with radicals and other reactive species faster than biological substrates do. The aim of the present study was to determine the in vitro antioxidant activity of aqueous extracts from leaves of Bauhinia forficata Link (Fabaceae - Caesalpinioideae) and Cissus sicyoides L. (Vitaceae) (two medicinal plants used popularly in the control of diabetes mellitus), using several different assay systems, namely, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) decolorization. superoxide anion radical (O-2 center dot-) scavenging and myeloperoxidase (MPO) activity. In the ABTS assay for total antioxidant activity, B. forficata showed IC50 8.00 +/- 0.07 mu g/mL, while C. sicyoides showed IC50 13.0 +/- 0.2 mu g/mL. However, the extract of C. sicyoides had a stronger effect on O-2 center dot- (IC50 60.0 +/- 2.3 mu p/mL) than the extract of B. forficata (IC50 90.0 +/- 4.4 mu g/mL). B. forficata also had a stronger inhibitory effect on MPO activity, as measured by guaiacol oxidation, than C. sicyoides. These results indicate that aqueous extracts of leaves of B. forficata and C. sicyoides are a potential source of natural antioxidants and may be helpful in the prevention of diabetic complications associated with oxidative stress.

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The fate of four new fungicides (cyprodinil, fludioxonil, pyrimethanil, and tebuconazole) from the treatment on vine to the production of wine was studied. The influence of clarifying agents (bentonite, charcoal, potassium caseinate, gelatin, and polyvinylpolypyrrolidone) on residue concentrations in wine was also studied. The fungicide residues on grapes showed different decay rates after treatment, with first-order kinetics and half-lives ranging from 8 to 57 days. Grape processing into wine caused considerable residue reduction with cyprodinil (ca. 80%), fludioxonil (ca. 70%), and tebuconazole (ca. 50%) and no reduction with pyrimethanil. The two wine-making techniques employed (with and without maceration) had the same influence on the residue concentrations in wine, except for fludioxonil which showed maximum residue reduction with vinification with maceration. Among the clarifying agents tested, only charcoal showed effective action on the elimination of residue content in wine, proving complete elimination, or almost, of fungicide residues.