Flavonoids and other bioactive phenolics isolated from Cenostigma macrophyllum (Leguminosae)

This work describes the phytochemical study of stem bark and leaves of Cenostigma macrophyllum Tul. (Leguminosae). Through usual chromatographic techniques were isolated bergenin as the primary compound of the stem bark of and from the leaves gallic acid, methyl gallate, ellagic acid, quercetin, quercetin-3-O-β-D-glucopyranoside, quercetin-3-O-(6"-O-galloyl)-β-D-glucopyranoside (tellimoside), quercetin-3-O-(6"-O-E-p-coumaroyl)-β-D-glucopyranoside (helichrysroside), agathisflavone and vitexin were obtained. The isolates were identified by spectroscopic data analysis, and bergenin showed dose-related antinociception when assessed in acetic acid-induced writhing in mice

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

BIOLOGICAL ACTIVITIES OF EXTRACTS FROM PADINA BOERGESENII AND SARGASSUM STENOPHYLLUM, SEAWEEDS NATURALLY FOUND IN BAIA DE TODOS OS SANTOS, BRAZIL

Objective: Here we present the results of the biological potential as antioxidant, anti-cancer and leishmaniscidal from extracts of Padina boergesenii Allender & Kraft and of Sargassum stenophyllum Martius, seaweed species commonly found in bay of the Brazilian Atlantic coast named Baía de Todos os Santos, state Bahia. In addition, we reported on the chemical composition of extractive fractions from these algae.Methods: Phytochemicals prospecting methods such as thin layer chromatography (TLC) and spectrometry in the UV/Vis region were used to identify the chemical class of constituents from these algae extracts. Antioxidant potential of the fractions was evaluated using the α,α-diphenyl-β-picrylhydrazyl (DPPH) free radical scavenging method. The cytotoxic potential of seaweed extracts against the human breast cancer (MFC-7) cell lines was evaluated using the sulforhodamine B (SRB) colorimetric assay. The leishmanicidal effect of algae extracts against promastigotes of Leishmania amazonenses Laison & Shaw 1972 was evaluated using amphotericin B (AMB) as positive control.Results: Were detected flavonoids, steroids, carotenoids, anthocyanins and phenolic compounds from algae extracts in hexane, chloroform and n-butanol. Overall, extractive fractions showed moderate antioxidant activities in comparison with quecertin, butylated hydroxytoluene and gallic acid. Fractions from P. boergesenii and chloroform fraction of S. stenophyllum presented significant activity against MCF-7 cells by inhibiting the cells grown among 55.0 to 66.0 %. These results were closely similar to inhibition reached by colchicine (67.0 %) used as positive control. No antileishmanial significant effect was observed for P. boergesenii and S. stenophyllum extracts at the tested conditions.Conclusion: The results indicated a promissory pharmacologic potential for the P. boergesenii and S. stenophyllum extracts, Which open perspectives to the isolation of their active constituents.Â

Antioxidant activities of isolated compounds from stems of Mimosa invisa Mart. ex Colla

This work describes the phytochemical study of stems of Mimosa invisa (Mimosaceae) and the evaluation of the antioxidant potential of isolated compounds. Cromatografic techniques were employed to isolate salicifoliol, pinoresinol, quercetin, quercetin-3-O-rhamnopyranosyl, quercetin-3-O-arabinofuranosyl lupeol, β-amyrin, sitosterol, p-hydroxy coumaric acid, 4-hydroxy-3-methoxy benzaldehyde (vanillin), 4-hydroxy-3,5-dimethoxy benzaldehyde, 4-hydroxy-3-methoxy benzoic acid and 4',6,7- trimethoxy flavonol. The latter had been previously described but the spectrometric data shown indicated the structure required review. The antioxidant activity of the compounds was evaluated by the DPPH test and capability of NBT reduction by superoxide radicals. Quercetin glycosides showed lower antioxidant potential than quercetin and, salicifoliol was found to be more active than pinoresinol