Essential oil composition and antichemotactic activity of Stenachaenium Benth. species native to South Brazil

Chemical composition of essential oils from four Stenachaenium species from South Brazil were established by gas chromatography coupled with mass spectrometry (GC/MS). The major compounds identified in the oil of S. megapotamicum were a coumarin derivative, 2H-1-benzopyran-2-one,7-(3-methylbutoxy) (24.0%), β-bisabolene (12.8%) and thymol methyl ether (7.1%). The oil of S. adenanthum contained mainly pogostol (14.0%). S. riedelli oil showed significant presence of aliphatic compounds, with predominance of hexadecanoic acid in all samples (leaves, inflorescence and leaves collected during of inflorescence period). Hexadecanoic acid (23.8%) was also the main component in S. macrocephalum. Concerning antichemotactic activity, all the oil samples tested showed a significant leukocyte migration inhibition compared to chemotactic stimulant (lipopolysaccharide from Escherichia coli - LPS), at concentrations of 1 to 5 μg/mL, except for S. adenanthum. These results suggest that the essential oils of some Stenachaenium species could inhibit acute inflammatory process, because the migration of neutrophils occurs mainly in the early inflammatory process

Palynological analysis of a late Holocene core from Santo Antônio da Patrulha, Rio Grande do Sul, Southern Brazil

A sedimentar core collected at Santo Antônio da Patrulha, Rio Grande do Sul State, southmost Brazil, was submitted to pollen analysis to provide the vegetational history of this region, and the paleoecological and paleoclimatic changes. A total of 98 taxa of palynomorphs was identified from 35 subsamples. Three radiocarbonic datings were obtained along a section of 115 cm depth, including the basal age of 4730 ± 50 yr BP. Pollen diagrams and cluster analysis were performed based on palynomorphs frequencies, demonstrating five distinct phases (SAP-I to SAP-V), which reflected different paleoecological conditions. The predominance of plants associated with grasslands in the phase SAP-I suggests warm and dry climate conditions. A gradual increasing of humidity conditions was observed mainly from the beginning of the phase SAP-III, when the vegetation set a mosaic of grasslands and Atlantic rainforest. Furthermore, the presence of some forest taxa ( Acacia-type, Daphnopsis racemosa, Erythrina-type and Parapiptadenia rigida-type), from the phase SAP-IV, is interpreted as an influence of the seasonal semideciduous forest in the study region. From the phase SAP-V (ca. 4000 yrs BP), the vegetation became similar to the modern one (extant Atlantic rainforest Biome), especially after 2000 yrs BP (calibrated age).Um testemunho de sondagem coletado em Santo Antônio da Patrulha, Rio Grande do Sul, Brasil, foi submetido para análise polínica a fim de revelar a história vegetacional e mudanças paleoecológicas e paleoclimáticas. Um total de 98 táxons foi identificado a partir de 35 subamostras. Três datações radiocarbônicas foram obtidas ao longo de uma seção de 115 cm de profundidade, incluindo a idade basal de 4730 ± 50 anos AP. Diagramas polínicos e análises de agrupamentos foramrealizadas com base nas freqüências dos palinomorfos, demonstrando cinco fases distintas (SAP-I a SAP-V), as quais refletiram diferentes condições paleoecológicas. A predominância de plantas relacionadas à vegetação campestre na fase SAP-I sugere condições climáticas quentes e secas. Um gradual aumento nas condições de umidade foi observado principalmente no início da fase SAP-III, quando a vegetação conformou um mosaico de Campos e Floresta Atlântica. Além disso, a presença de certos táxons florestais (tipo- Acacia, Daphnopsis racemosa, tipo Erythrina e tipo Parapiptadenia rigida), a partir da fase SAP-IV, é interpretada como influência da Floresta Estacional Semidecidual na região de estudo. A partir da fase SAP-V (ca. 4000 anos AP) a vegetação tornou-se similar à moderna (atual Bioma da Floresta Atlântica), especialmente após 2000 anos AP (idade calibrada)

The complete genome sequence of Chromobacterium violaceum reveals remarkable and exploitable bacterial adaptability

Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals (i) extensive alternative pathways for energy generation, (ii) ≈500 ORFs for transport-related proteins, (iii) complex and extensive systems for stress adaptation and motility, and (iv) wide-spread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for the detoxification of xenobiotics that may have biotechnological applications

Analysis of flavonoids in Rubus erythrocladus and Morus nigra leaves extracts by liquid chromatography and capillary electrophoresis

AbstractThis study uses high performance liquid chromatography and capillary electrophoresis as analytical tools to evaluate flavonoids in hydrolyzed leaves extracts of Rubus erythrocladus Mart., Rosaceae, and Morus nigra L., Moraceae. For phytochemical analysis, the extracts were prepared by acid hydrolysis and ultrasonic bath and analyzed by high performance liquid chromatography using an ultraviolet detector and by capillary electrophoresis equipped with a diode-array detector. Quercetin and kaempferol were identified in these extracts. The analytical methods developed were validated and applied. Quercetin and kaempferol were quantified in R. erythrocladus, with 848.43 ± 66.68 μg g-1 and 304.35 ± 17.29 μg g-1, respectively, by HPLC-UV and quercetin, 836.37 ± 149.43 μg g-1, by CE-DAD. In M. nigra the quantifications of quercetin and kaempferol were 2323.90 ± 145.35 μg g-1 and 1446.36 ± 59.00 μg g-1, respectively, by HPLC-UV and, 2552.82 ± 275.30 μg g-1 and 1188.67 ± 99.21 μg g-1, respectively, by CE-DAD. The extracts were also analyzed by ultra-performance liquid chromatography coupled with a diode-array detector and mass spectrometer (MS), UPLC-DAD/MS