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1.
Bol. latinoam. Caribe plantas med. aromát ; 11(6): 542-548, nov. 2012. tab
Article in English | LILACS | ID: lil-723584

ABSTRACT

In the present study we investigated the chemical composition of hexane fraction and essential oil of Stachytarpheta gesnerioides (Verbenaceae) by GC-MS, total phenol and flavonoid contents. The antioxidant capacity and antimicrobial activity were investigated in five extracts of leaves of S. gesnerioides. Aqueous and 100 percent ethanol extracts were prepared by dynamic maceration. Hexane, ethyl acetate and methanol extracts were prepared by Soxhlet extraction. The essential oil (EO) and hexane fraction (HF) are mainly composed by guaiol. Moreover, the HF is also rich in the monoterpene alpha-pinene. The total phenol content ranged from 0.85 to 22.74 mg gallic acid equivalent /100mg dry extract at Folin–Ciocalteu’s reagent method. The total flavonoid concentration ranged from 0.68 to 13.65 mg rutin equivalent /100mg dry extract, detected using 8 percent aluminium chloride. The ethyl acetate extract (IC50=9.41 ug/ml) showed the highest antioxidant activity. The extracts were found to be effective to inhibit the microorganisms tested.


Se han investigado la composición química de la fracción hexánica (FH) y aceite esencial (AE) de Stachytarpheta gesnerioides (Verbenaceae) por GC-MS, el contenido de fenoles totales y flavonoides. La capacidad antioxidante y actividad antimicrobiana fueron investigadas en cinco extractos de hojas de S gesnerioides. Extractos acuosos y etanolico fueron preparados por la maceración dinámica y extracción continua en Soxhlet con hexano, acetato de etilo y metanol. Las fracciones AE y FH están compuestas principalmente por guaiol. La fracción FH es también rica en alfa-pineno. El contenido de fenoles totales varió desde 0,85 hasta 22,74 mg de ácido gálico/100 mg de extracto seco (Folin-Ciocalteu). La concentración total de flavonoides varió desde 0,68 hasta 13,65 mg en equivalentes de rutina/100 mg de extracto seco, que se detectó mediante reacción con cloruro de aluminio al 8 por ciento. El extracto de acetato de etilo (CI50=9,41 ug/ml) enseño la más grande actividad antioxidante. Los extractos se encontraron eficaces para inhibir los microorganismos ensayados.


Subject(s)
Oils, Volatile/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Verbenaceae/chemistry , Phenols/analysis , Flavonoids/analysis , Gas Chromatography-Mass Spectrometry , Hexanes/chemistry , Microbial Sensitivity Tests , Plant Leaves
2.
Braz. arch. biol. technol ; 52(4): 893-899, July/Aug. 2009. ilus
Article in English | LILACS | ID: lil-525610

ABSTRACT

Since previous cytogenetic reports of Aloysia have only described the meiotic behavior and chromosomal number of some species, the aim of this work was to provide detailed cytogenetic description of Aloysia virgata that would contribute to the understanding of the taxonomical organization of the Verbenaceae. Aloysia virgata had a karyotype with 2n = 36 metacentric chromosomes, all with similar size. The large amount of heterochromatin seen after Giemsa staining was confirmed by C-banding. Four nucleolar organizer regions (NORs) were detected with an rDNA 45S probe in two homologous pairs and two sites of 5S rDNA located on one chromosomal pair were detected by fluorescence in situ hybridization. The interphase nucleus was classified as semi-reticulate. Meiotic analysis showed a normal chromosomal behavior, with 18 bivalents in some parts of prophase I and in metaphase I. The number of chromosomes, NORs and 5S rDNA segments did not exclude a possible polyploid origin.


O gênero Aloysia reúne aproximadamente 30 espécies, porém sua circunscrição tem sido motivo de controvérsia. São poucos os estudos citogenéticos para o gênero, relatando apenas o número e o comportamento cromossômico. O presente trabalho teve como objetivo, identificar os caracteres citogenéticos de Aloysia virgata da flora brasileira que possam ser utilizados para um melhor entendimento e caracterização dos aspectos citogenéticos da família Verbenaceae, que possam contribuir para a organização taxonômica do grupo. Aloysia virgata apresentou cariótipo com 2n = 36 pequenos cromossomos, todos com o mesmo tamanho. Grande quantidade de heterocromatina foi observada com Giemsa e confirmada pela técnica de banda C. Foram detectadas quatro regiões organizadoras de nucléolo (NORs) e dois sítios de rDNA 5S pela técnica de hibridação in situ fluorescente (FISH). O núcleo interfásico foi classificado como semireticulado. Foi realizada a caracterização meiótica, na qual os cromossomos apresentaram comportamento normal, com a presença de 18 bivalentes na prófase I e na metáfase I. O número de cromossomos, de NORs e de segmentos de DNAr 5S não excluem uma possível origem poliplóide.

3.
Genet. mol. biol ; 31(1): 141-145, 2008. graf, tab, ilus
Article in English | LILACS | ID: lil-476164

ABSTRACT

The cytotoxicity effect of aqueous extracts of the lichens species Myelochroa lindmanii and Canoparmelia texana (Lecanorales, Parmeliaceae) were evaluated using meristematic cells of lettuce (Lactuca sativa) and maize (Zea mays). The seasonal effect was also evaluated. Extracts of M. lindmanii and C. texana inhibited root growth and/or percentage germination, possibly due to alterations in the cell cycle. The M. lindmanii extract showed anti-mitotic effects and blocked the cell cycle in metaphase so that c-mitosis and cells with chromosome duplication were produced. The C. texana extract appeared to hinder cell division, increasing the number of interphase cells. In addition, both extracts caused an increase in percentage of cell death. Clastogenic effects were also observed, such as sticky chromosomes, bridges, fragments and later segregation. Both lichen species are thus potential sources of biologically active substances with possible applications in biology, medicine and agronomy.


Subject(s)
Cytotoxicity, Immunologic , Lichens , Mutagens , Biological Assay , Germination , Lactuca , Mitotic Index , Zea mays
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