Chemical composition and biological activities of the essential oils from Vitex-agnus castus, Ocimum campechianum and Ocimum carnosum.

The essential oils obtained by hydrodistillation from fresh leaves of Vitex agnus-castus and Ocimum campechianum, and from fresh inflorescences of Ocimum carnosum were analysed by GC-FID and GC-MS. The major components of V. agnus-castus essential oil were identified as 1,8-cineole (47.9%), terpinyl α-acetate (11.6%), sabinene (11.2%) and caryophyllene oxide (9.7%), while in the O. campechianum essential oil were eugenol (72.1%), ß-elemene (6.8%), (E)-caryophyllene (6.4%) and bicyclogermacrene (5.2%). Linalool (79.0%), α-epi-cadinol (5.4%), terpinen-4-ol (3.2%) and 1,8-cineole (2.8%) were the major constituents in the O. carnosum essential oil. The essential oils were subsequently evaluated for their larvicidal and cytotoxic activities. Larval bioassay against Aedes aegypti of V. agnus-castus, O. campechianum and O. carnosum essential oils showed LC50 values of 97.55 ± 0.35, 81.45 ± 0.35 and 109.49 ± 0.35 µg/mL, respectively. The in vitro cytotoxic activities of the essential oils has been evaluated on breast adenocarcinoma (MCF-7), lung carcinoma (NCI-H292), pro-myelocytic leukemia (HL-60), and cervical adenocarcinoma (HEP-2) human cell lines, and pro-myelocytic leukemia cells lines (HL-60) were found to be the most sensitive to all the essential oils tested than the others. This is the first report on larvicidal and cytotoxic activities of these essential oils.

Antibiotic-Potentiating Activity of Phanostenine Isolated from Cissampelos sympodialis Eichler.

Cissampelos sympodialis Eichler is well studied and investigated for its antiasthmatic properties, but there are no data in the literature describing antibacterial properties of alkaloids isolated from this botanical species. This work reports the isolation and characterization of phanostenine obtained from roots of C. sympodialis and describes for the first time its antimicrobial and antibiotic modulatory properties. Phanostenine was first isolated from Cissampelos sympodialis and its antibacterial activities were determined. Chemical structures of the alkaloid isolate were determined using spectroscopic and chemical analyses. Phanostenine was also tested for its antibacterial activity against standard strains and clinical isolates of Escherichia coli and Staphylococcus aureus. Minimal inhibitory concentration (MIC) was determined in a microdilution assay and for the evaluation of antibiotic resistance-modifying activity. MIC of the antibiotics was determined in the presence or absence of phanostenine at sub-inhibitory concentrations. The evaluation of antibacterial activity by microdilution assay showed activity for all strains with better values against S. aureus ATCC 12692 and E. coli 27 (787.69 mm). The evaluation of aminoglycoside antibiotic resistance-modifying activity showed reduction in the MIC of the aminoglycosides (amikacin, gentamicin and neomycin) when associated with phanostenine, MIC reduction of antibiotics ranging from 21 % to 80 %. The data demonstrated that phanostenine possesses a relevant ability to modify the antibiotic activity in vitro. We can suggest that phanostenine presents itself as a promising tool as an adjuvant for novel antibiotics formulations against bacterial resistance.

7-epi-griffonilide, a new lactone from Bauhinia pentandra: complete 1H and 13C chemical shift assignments.

A new lactone, 7-epi-griffonilide (1), and six known compounds, 2, 3a - 3c, 4a and 4b, were isolated from the leaves of Bauhinia pentandra (Fabaceae). The structures elucidation of 1 and 2 were based on detailed 2D NMR techniques and spectral comparison with related compounds, leading to complete assignment of the 1H and 13C NMR spectra.

Synthesis of Benzyl Acetate Catalyzed by Lipase Immobilized in Nontoxic Chitosan-Polyphosphate Beads.

Enzymes serve as biocatalysts for innumerable important reactions, however, their application has limitations, which can in many cases be overcome by using appropriate immobilization strategies. Here, a new support for immobilizing enzymes is proposed. This hybrid organic-inorganic support is composed of chitosan-a natural, nontoxic, biodegradable, and edible biopolymer-and sodium polyphosphate as the inorganic component. Lipase B from Candida antarctica (CALB) was immobilized on microspheres by encapsulation using these polymers. The characterization of the composites (by infrared spectroscopy, thermogravimetric analysis, and confocal Raman microscopy) confirmed the hybrid nature of the support, whose external part consisted of polyphosphate and core was composed of chitosan. The immobilized enzyme had the following advantages: possibility of enzyme reuse, easy biocatalyst recovery, increased resistance to variations in temperature (activity declined from 60 °C and the enzyme was inactivated at 80 °C), and increased catalytic activity in the transesterification reactions. The encapsulated enzymes were utilized as biocatalysts for transesterification reactions to produce the compound responsible for the aroma of jasmine.

Synthesis, antibacterial and cytotoxic activities of new biflorin-based hydrazones and oximes.

Biflorin 1 is a biologically active quinone, isolated from Capraria biflora. Five new biflorin-based nitrogen derivatives were synthesized, of which two were mixtures of (E)- and (Z)- isomers: (Z)-2a, (Z)-2b, (Z)-3a, (Z)- and (E)-3b, (Z)- and (E)-3c. The antibacterial activity was investigated using the microdilution method for determining the minimum inhibitory concentration (MIC) against six bacterial strains. Tests have shown that these derivatives have potential against all bacterial strains. The cytotoxic activity was also evaluated against three strains of cancer cells, but none of the derivatives showed activity.

New Cytotoxic Bibenzyl and Other Constituents from Bauhinia ungulata L. (Fabaceae).

A new bibenzyl, 2'-hydroxy-3,5-dimethoxy-4-methylbibenzyl (1) and four known compounds identified as 2'-hydroxy-3,5-dimethoxybibenzyl (2), liquiritigenin (3), guibourtinidol (4) and fisetinidol (5) were isolated from the roots of Bauhinia ungulata L. Phytochemical investigations of the stems of B. ungulata led to the isolation of the known compounds identified as liquiritigenin (3), guibourtinidol (4), fisetinidol (5), taraxerol (6), betulinic acid (7), taraxerone (8), glutinol (9), a mixture of sitosterol (10) and stigmasterol (11), pacharin (12), naringenin (13) and eriodictyol (14). The structures of these compounds were elucidated on the basis of their spectral data (IR, MS, 1D- and 2D-NMR). The cytotoxicity of the bibenzyl 1 has been evaluated against four human cancer cell lines, showing the IC50 values of 4.3 and 6.5 µg ml-1 against pro-myelocytic leukemia (HL-60) and cervical adenocarcinoma (HEP-2) cell lines, respectively. This article also registers for the first time the 13 C-NMR data of the known bibenzyl 2.

Biflorin: an o-naphthoquinone of clinical significance.

Biflorin is an o-naphthoquinone with proven cytotoxic effects on tumor cells showing antimicrobial, antitumor and antimutagenic activities. Biflorin is an isolated compound taken from the roots of the plant Capraria biflora L. (Schrophulariaceae), indigenous of the West Indies and South America, which is located in temperate or tropical areas. This compound has shown to be strongly active against grampositive and alcohol-acid-resistant bacteria. It has been efficient in inhibiting the proliferation tumor cell lines CEM, HL-60, B16, HCT-8 and MCF-7. Recently, SK-Br3 cell line was treated with biflorin showing important cytotoxic effects. In this article, information related to the first structural characterization studies are presented, as well as the latest reports concerning the biological activity of this molecule.

Antibacterial and antioxidant activities of ursolic acid and derivatives.

Ursolic acid, an important bioactive compound, was isolated from ethanol extract of aerial parts of Sambucus australis. In order to develop bioactive ursolic acid derivatives, two semi-synthetic compounds were obtained through modification at C-3. The antibacterial activity of the ursolic acid and its derivatives was investigated. The microdilution method was used for determination of the minimal inhibitory concentration (MIC), against twelve bacterial strains. The influence of ursolic acid and its derivatives on the susceptibility of some bacterial pathogens to the aminoglycosides antibiotics neomycin, amikacin, kanamycin and gentamicin was evaluated. The most representative synergistic effect was observed by 3ß-formyloxy-urs-12-en-28-oic acid at the concentration of 64 µg/mL in combination with kanamycin against Escherichia coli (27), a multidrug-resistant clinical isolate from sputum, with reduction of MIC value from 128 µg/mL to 8 µg/mL. Ursolic acid and its derivatives were examined for their radical scavenger activity using the DPPH assay, and showed significant activity.

Magnetic nanosystem for cancer therapy using oncocalyxone a, an antitomour secondary metabolite isolated from a Brazilian plant.

This paper describes the investigation and development of a novel magnetic drug delivery nanosystem (labeled as MO-20) for cancer therapy. The drug employed was oncocalyxone A (onco A), which was isolated from Auxemma oncocalyx, an endemic Brazilian plant. It has a series of pharmacological properties: antioxidant, cytotoxic, analgesic, anti-inflammatory, antitumor and antiplatelet. Onco A was associated with magnetite nanoparticles in order to obtain magnetic properties. The components of MO-20 were characterized by XRD, FTIR, TGA, TEM and Magnetization curves. The MO-20 presented a size of about 30 nm and globular morphology. In addition, drug releasing experiments were performed, where it was observed the presence of the anomalous transport. The results found in this work showed the potential of onco A for future applications of the MO-20 as a new magnetic drug release nanosystem for cancer treatment.

In silico and in vitro evaluation of efflux pumps inhibition of α,ß-amyrin.

The use of the bacterial efflux pump mechanism to reduce the concentrations of antibiotics in the intracellular to the extracellular region is one of the main mechanisms by which bacteria acquire resistance to antibiotics. The present study aims to evaluate the antibacterial activity of the α,ß-amyrin mixture isolated from Protium heptaphyllum against the multidrug-resistant strains of Escherichia coli 06 and Staphylococcus aureus 10, and to verify the inhibition of the efflux resistance mechanisms against the strains of S. aureus 1199B and K2068, carrying the NorA and MepA efflux pumps, respectively. The α,ß-amyrin did not show clinically relevant direct bacterial activity. However, the α,ß-amyrin when associated with the gentamicin antibiotic presented synergistic effect against the multidrug-resistant bacterial strain of S. aureus 10. In strains with efflux pumps, α,ß-amyrin was able to inhibit the action of the efflux protein NorA against Ethidium Bromide. However, this inhibitory effect was not observed in the MepA efflux pump. In addition, when evaluating the effect of standard efflux pump inhibitors, clorptomazine and CCCP, α,ß-amyrin showed a decrease in MIC, demonstrating the presence of the efflux mechanism through synergism. Docking studies indicate that α, ß-amyrin have a higher affinity energy to MepA, and NorA than ciprofloxacin and norfloxacin. Also, α, ß-amyrin bind to the same region of the binding site as these antibiotics. It was concluded that the α, ß-amyrin has the potential to increase antibacterial activity with the association of antibiotics, together with the ability to be a strong candidate for an efflux pump inhibitor.Communicated by Ramaswamy H. Sarma.

Amyrin esters induce cell death by apoptosis in HL-60 leukemia cells.

Four derivatives of an α,ß-amyrin mixture were synthesized by acylation with appropriate anhydrides. The structures of the compounds were confirmed by means of IR and (1)H and (13)C NMR. The compounds were screened for cytotoxic activity using four human tumor cell lines (HL-60, MDAMB-435, SF-295 and HCT-8) and normal peripheral blood mononuclear cells (PBMC). 3-O-Carboxymaleinate of α,ß-amyrin (3a/3b) were found to be the only active compounds of the series (high cytotoxicity), showing IC(50) values ranging from 1.8 to 3µM. In PBMC, 3a/3b were not toxic, suggesting selectivity for tumor cells. To better understand the mechanism of action involved in the cytotoxicity of 3a/3b, HL-60 cells treated with 3a/3b were examined for morphological changes, DNA fragmentation, cell cycle perturbation, externalization of phosphatidylserine and activation of caspases 3/7, with doxorubicin serving as the positive control. The results indicate that the cytotoxicity of 3a/3b involves the induction of cell death by apoptosis.

Evaluation of the cytotoxic and antimutagenic effects of biflorin, an antitumor 1,4 o-naphthoquinone isolated from Capraria biflora L.

Biflorin is a natural quinone isolated from Capraria biflora L. Previous studies demonstrated that biflorin inhibits in vitro and in vivo tumor cell growth and presents potent antioxidant activity. In this paper, we report concentration-dependent cytotoxic, genotoxic, antimutagenic, and protective effects of biflorin on Salmonella tiphymurium, yeast Saccharomyces cerevisiae, and V79 mammalian cells, using different approaches. In the Salmonella/microsome assay, biflorin was not mutagenic to TA97a TA98, TA100, and TA102 strains. However, biflorin was able to induce cytotoxicity in haploid S. cerevisiae cells in stationary and exponential phase growth. In diploid yeast cells, biflorin did not induce significant mutagenic and recombinogenic effects at the employed concentration range. In addition, the pre-treatment with biflorin prevented the mutagenic and recombinogenic events induced by hydrogen peroxide (H(2)O(2)) in S. cerevisiae. In V79 mammalian cells, biflorin was cytotoxic at higher concentrations. Moreover, at low concentrations biflorin pre-treatment protected against H(2)O(2)-induced oxidative damage by reducing lipid peroxidation and DNA damage as evaluated by normal and modified comet assay using DNA glycosylases. Our results suggest that biflorin cellular effects are concentration dependent. At lower concentrations, biflorin has significant antioxidant and protective effects against the cytotoxicity, genotoxicity, mutagenicity, and intracellular lipid peroxidation induced by H(2)O(2) in yeast and mammalian cells, which can be attributed to its hydroxyl radical-scavenging property. However, at higher concentrations, biflorin is cytotoxic and genotoxic.

Biflorin inhibits the proliferation of gastric cancer cells by decreasing MYC expression.

Gastric cancer is the third leading cause of cancer-related death worldwide. To evaluate the anticancer potential and molecular mechanism of biflorin, a prenyl-ortho-naphthoquinone obtained from Capraria biflora L. roots, we used ACP02, a gastric cancer cell line established from a primary diffuse gastric adenocarcinoma. In this study, biflorin was shown to be a potent cytotoxic agent against ACP02 by Alamar Blue and Trypan Blue assays. Morphological analysis indicated cell death with features of necrosis. Furthermore, a decrease in colony formation, migration and invasion of ACP02 cells was observed after treatment with biflorin (1.0, 2.5 and 5.0 µM). Regarding the underlying molecular mechanism of biflorin in ACP02 cells, we observed a decrease in MYC expression and telomere length using FISH. Our findings suggest a novel molecular target of biflorin in ACP02 cells, which may be a significant therapeutic approach for gastric cancer management.

A new heterofunctional support for enzyme immobilization: PEI functionalized Fe3O4 MNPs activated with divinyl sulfone. Application in the immobilization of lipase from Thermomyces lanuginosus.

Lipase from Thermomyces lanuginosus (TLL) was immobilized onto a novel heterofunctional support, divinyl sulfone (DVS) superparamagnetic nanoparticles (SPMNs) functionalized with polyethyleneimine (PEI). Particle size and zeta potential measurements, elemental analysis, X-ray powder diffraction, magnetic measurements, and infrared spectroscopy analysis were used to characterize the TLL preparations. At pH 10, it was possible to achieve 100 % of immobilization yield in 1 h. The immobilization pH gives TLL preparations with different stabilities; indeed the TLL preparation immobilized at pH 5.0 was the most stable during the thermal inactivation at all pH values. For the hydrolysis of racemic methyl mandelate, the nanobiocatalysts immobilized at pH 5.0 and blocked with ethylenediamine (EDA) and ethanolamine (ETA) obtained good enantioselectivities (68 % and 72 %, respectively) with high catalytic activities in the reaction medium at pH 7.0. The operational stability of the systems was evaluated in the esterification reaction of benzyl alcohol, obtaining up to 61 % conversion after the seventh reaction cycle. These results show that SPMN@PEI-DVS support is a robust strategy for the easy and rapid recovery of the nanobiocatalyst by applying a magnetic field, showing great potential for industrial applications.

Cytotoxic diterpenoids from Croton argyrophylloides.

Two new diterpenes, 1 and 2, together with the known ent-15-oxo-kaur-16-en-18-oic acid (3), were isolated from the bark of Croton argyrophylloides. The structural characterization of 1 and 2 was determined on the basis of spectroscopic data interpretation. The cytotoxicity of each compound was evaluated against HL-60 (leukemia), MDAMB-435 (melanoma), SF-295 (glioblastoma), and HCT-8 (colon carcinoma) human tumor cell lines and against human peripheral blood mononuclear cells. The hemolytic potential in mouse erythrocytes was also tested for 1-3.

Effects of 1,8-cineole on electrophysiological parameters of neurons of the rat superior cervical ganglion.

1. 1,8-Cineole is a non-toxic small terpenoid oxide believed to have medicinal properties in folk medicine. It has been shown to have various pharmacological effects, including blockade of the compound action potential (AP). In the present study, using intracellular recording techniques, we investigated the effects of 1,8-cineole on the electrophysiological parameters of neurons of the superior cervical ganglion (SCG) in rats. 2. 1,8-Cineole (0.1-6 mmol/L) showed reversible and concentration-dependent effects on various electrophysiological parameters. At 3 and 6 mmol/L, but not at 0.1 and 1 mmol/L, 1,8-cineole significantly diminished the input resistance (R(i)) and altered the resting potential (E(m)) to more positive values. At 6 mmol/L, 1,8-cineole completely blocked all APs within 2.7 +/- 0.6 min (n = 12). In neurons exposed to 3 and 1 mmol/L 1,8-cineole, the effects regarding excitability varied from complete AP blockade to minor inhibition of AP parameters. The depolarization of E(m) and the decrease in R(i) induced by 6 mmol/L 1,8-cineole were unaltered by 200 micromol/L niflumic acid, a well known blocker of Ca(2+)-activated Cl(-) currents. 3. Significant correlations (Pearson correlation test) were found between changes in E(m) and decreases in AP amplitude (r = -0.893; P < 0.00282) and maximum ascendant inclination (r = -0.799; P < 0.0173), but not for maximum descendant inclination (r = 0.598; P < 0.117). Application of current to restore the transmembrane potential equal to control E(m) values in the presence of 6 mmol/L 1,8-cineole resulted in the partial recovery of AP. 4. The present study shows that 1,8-cineole effectively blocks the excitability of SCG neurons, probably through various mechanisms, one of which acts indirectly via depolarization of the neuronal cytoplasmatic membrane.

Quinones from plants of northeastern Brazil: structural diversity, chemical transformations, NMR data and biological activities.

The present review focus in quinones found in species of Brazilian northeastern Capraria biflora, Lippia sidoides, Lippia microphylla and Tabebuia serratifolia. The review cover ethnopharmacological aspects including photography of species, chemical structure feature, NMR datea and biological properties. Chemical transformations of lapachol to form enamine derivatives and biological activities are discussed.

Bioreduction of aldehydes and ketones using Manihot species.

Biocatalysis constitutes an important tool in organic synthesis, especially for the preparation of chiral molecules of biological interest. A series of aliphatic and aromatic aldehydes and two ketones were reduced using plant cell preparations from Manihot esculenta and Manihot dulcis roots. The reduced products were typically obtained in excellent yields (80-96%), and with excellent enantiomeric excess (94-98%), except for vanillin. Esters, a nitrile, and an amide were also examined, but were not reduced. Preliminary conversion rate studies are reported. This is the first attempt to perform the biotransformation of carbonyl compounds using Manihot species.

Antioxidant, icthyotoxicity and brine shrimp lethality tests of Magonia glabrata.

The ethanolic extract of the fruit bark from Magonia glabrata yielded shikimic acid, scopoletin, sitosterol glycoside and 2-O-methyl-l-inositol. Antioxidant, icthyotoxicity and brine shrimp lethality activities were observed in this extract. The major constituent, 2-O-methyl-l-inositol, was found to be inactive in two assays but showed moderate activity as a radical scavenger.

Bioactivity of biflorin, a typical o-naphthoquinone isolated from Capraria biflora L.

Capraria biflora L. (Scrophulariaceae) is a perennial shrub widely distributed in several countries of tropical America. The present work verified the cytotoxic and antioxidant potential of biflorin, an o-naphthoquinone isolated from C. biflora collected in the northeast region of Brazil. The cytotoxicity was tested on three different animal cell models: mouse erythrocytes, sea urchin embryos and tumor cells, while the antioxidant activity was assayed by the thiocyanate method. Biflorin lacked activity on mouse erythrocytes as well as on the development of sea urchin eggs, but strongly inhibited the growth of all five tested tumor cell lines, especially the skin, breast and colon cancer cells with IC50 of 0.40, 0.43 and 0.88 micro/ml for B16, MCF-7 and HCT-8, respectively. Biflorin also showed potent antioxidant activity against autoxidation of oleic acid in a water/alcohol system.