Francisco Arnaldo Viana

Antitumor Activity of the Essential Oil from the Leaves of Croton regelianus and Its Component Ascaridole

Croton regelianus Muell. Arg., popularly known as ‘velame‐de‐cheiro’, is a native plant from the Northeast of Brazil used in folk medicine to treat diseases of different kinds, including malignant tumors. In this study, the in vitro and in vivo antitumor effects of the essential oil from the leaves of C. regelianus and ascaridole, one of the main constituents, were investigated. In vitro, the essential oil and ascaridole displayed cytotoxicity, showing IC50 values in the range of 22.2 to 48.0 μg/ml in HL‐60 and SF‐295 cell lines for the essential oil, and 6.3 to 18.4 μg/ml in HL‐60 and HCT‐8 cells lines for ascaridole, respectively. The in vivo study, using sarcoma 180 as a tumor model, demonstrated inhibition rates of 28.1 and 31.8% for essential oil, at the 50 and 100 mg/kg, while ascaridole inhibition rates were 33.9% at 10 mg/kg and 33.3% at 20‐mg/kg doses. Histopathological examination showed that the organs were only weakly affected by the treatment. In conclusion, ascaridole has an interesting antitumor activity in sarcoma 180 murine model, probably related to the described cytotoxic activity, and, moreover, its presence in the essential oil from the leaves of C. regelianus could explain, at least in part, the ethnopharmacological use of this plant in the treatment of cancer.

Larvicidal and Nematicidal Activities of the Leaf Essential Oil of Croton regelianus

The chemical composition of the leaf essential oil of Croton regelianus collected from wild plants growing in two different sites at Ceará State (Brazil) was analyzed by GC/MS and GC‐FID. Twenty monoterpenoids, representing more than 96% of the chemical composition of the oils, were identified and quantified. The oils showed similar chemical composition but considerable variation in the levels of each constituent. Ascaridole (33.9–17.0%), p‐cymene (22.3–21.6%), and camphor (13.0–3.1%) were the predominant constituents. The monoterpene ascaridole was isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti and Artemia sp. larvae, and the root knot nematode Meloidogyne incognita. The bioassay results show that the essential oil of C. regelianus and ascaridole were moderately active against the M. incognita, but strongly effective against both A. aegypti and Artemia sp. larvae.

Oxidative stress induction by (+)-cordiaquinone J triggers both mitochondria-dependent apoptosis and necrosis in leukemia cells

(+)-Cordiaquinone J is a 1,4-naphthoquinone isolated from the roots of Cordia leucocephala that has antifungal and larvicidal effects. However, the cytotoxic effects of (+)-cordiaquinone J have never being explored. In the present study, the effect of (+)-cordiaquinone J on tumor cells viability was investigated, showing IC(50) values in the range of 2.7-6.6muM in HL-60 and SF-295 cells, respectively. Studies performed in HL-60 leukemia cells indicated that (+)-cordiaquinone J (1.5 and 3.0muM) reduces cell viability and 5-bromo-2-deoxyuridine incorporation after 24h of incubation. (+)-Cordiaquinone J showed rapid induction of apoptosis, as indicated by phosphatidylserine externalization, caspase activation, DNA fragmentation, morphologic changes, and rapid induction of necrosis, as indicated by the loss of membrane integrity and morphologic changes. (+)-Cordiaquinone J altered the redox potential of cells by inducing the depletion of reduced GSH intracellular content, the generation of reactive oxygen species and the loss of mitochondrial membrane potential. However, pre-treatment of cells with N-acetyl-l-cysteine abolished most of the observed effects related to (+)-cordiaquinone J treatment, including those involving apoptosis and necrosis induction.

Chemical Composition of the Essential Oil from Roots of Philodendron acutatum Schott

Abstract The essential oil from the roots of Philodedron acutatum, collected in the north of Brazil, was analyzed by GC/MS and retention indices. Six samples were obtained in three different dates. Thirty five components were identified, the main constituents were α-pinene (0–23.2%), β-pinene (0–21.8%), 2-undecanone (0–12.7%), 2-tridecanone (1.2–34.3%) and β-bisabolene (0.8–49.5%).

Chemical constituents of Cordia piauhiensis: Boraginaceae

A new monodesmoside triterpenoid saponin characterized as 3b-O-a-L-rhamnopyranosyl-(1®2)-b-D-glucopyranosyl pomolic acid, was isolated from Cordia piauhiensis Fresen (Boraginaceae). Its structure was determined by extensive NMR analysis, including 1H, 1H-COSY, HMQC, HMBC, and NOESY experiments. In addition, four known triterpenoids: quinovic acid, cincholic acid, cincholic 3b-O-6-deoxy-b-D-glucopyranoside acid and quinovic 3b-O-b-D-glucopyranoside acid were also isolated.

Essential Oil of Siparuna guianensis Aublet from the Amazon Region of Brazil

Abstract The essential oils obtained by steam distillation of the leaves, stem bark, stem wood, root bark, root wood and fruits of Siparuna guianensis were analyzed using a combination of GC/MS, retention indices and 13C-NMR spectroscopy. Epi-α-cadinol was the major component (11.9–39.9%) in almost all oils, except for the fruit and stem bark oils that contained 2-undecanone (52.7%) and terpinolene (33.3%) as main constituents, respectively.

Anti-inflammatory and antinociceptive effects of hydroalcoholic extract from Pseudobombax marginatum inner bark from caatinga potiguar

ETHNOPHARMACOLOGICAL RELEVANCE The Pseudobombax marginatum (St Hil) Rob., Malvaceae, is mentioned in ethnobotanical studies. It is used as anti-inflammatory, for ulcers and gastritis, and back pain. To evaluate anti-inflammatory and antinociceptive activities a hydroalcoholic extract (HE) from inner bark was prepared. MATERIALS AND METHODS For the anti-inflammatory activity, carrageenan-induced paw edema and peritonitis models, and also myeloperoxidase assay were used. For the antinociceptiva activity acetic acid-induced writhing, hot plate and formalin tests were employed. RESULTS The HE extract exhibited an intense inhibition in carrageenan-induced edema model and also in myeloperoxidase activity at the doses of 100 and 300 mg/kg. The leukocyte migration into the peritoneal cavity was also inhibited at the doses of 30, 100 and 300 mg/kg. A similar profile was observed against acid-induced abdominal contortions and in formalin second phase test at the doses of 30 and 100 mg/kg, but this treatment did not affect the behavior of animals in the hot plate test. CONCLUSIONS The experimental data of the HE from Pseudobombax marginatum show anti-inflammatory and antinociceptiva activities, confirming the indication from traditional medicine; however further studies are required to define and isolate the active anti-inflammatory and antinociceptiva components from this active specie.

Triterpenoid saponins from stem bark of Pentaclethra macroloba

Two new and two known triterpenoid saponins were isolated from the stem bark of Pentaclethra macroloba. Their structures were determined using a combination of homo- (1D 1H NMR, 13C NMR-HBBD and 13C NMR-DEPT) and heteronuclear 2D NMR techniques (1H-1H-COSY, 1H-1H-TOCSY, 1H-1H-NOESY, HMQC and HMBC), ESIMS and chemical methods. The structures of the two new pentacyclic triterpenoid saponins were established as 3b-O-{[b-D-glucopyranosyl-(1®3)-a-L-rhamnopyranosyl-(1®2)],b-D- glucopyranosyl-(1®4)}-a-L-arabinopyranosylhederagenin (3) and 3b-O-{[b-D-glucopyranosyl-(1®4)-b-D-glucopyranosyl-(1®3)-a-L-rhamnopyranosyl- (1®2)],b-D- glucopyranosyl(1®4)}-a-L-arabinopyranosyloleanolic acid (4).

1H and 13C NMR assignments for two new cordiaquinones from roots of Cordia leucocephala.

From the roots of Cordia leucocephala (Boraginaceae), two new meroterpenoid naphthoquinones, 6‐[10‐(12,12‐dimethyl‐13α‐hydroxy‐16‐methenyl‐cyclohexyl)ethyl]‐1,4‐naphthalenedione (cordiaquinone L) and 5‐methyl‐6‐[10‐(12,12‐dimethyl‐13β‐hydroxy‐16‐methenyl‐cyclohexyl)methyl‐1,4‐naphthalenedione (cordiaquinone M) were isolated. Their structures were elucidated after detailed 1D and 2D NMR (COSY, HSQC, HMBC and NOESY) data analyses and comparison with literature data for analogous compounds. Copyright

Chemical Composition of the Leaf Essential Oil of Cordia leucocephala Moric from Northeast of Brazil

Abstract The essential oil from leaves of Cordia leucocephala Moric (Boraginaceae) from northeast of Brazil was obtained by hydrodistillation and subsequently analyzed by GC/MS and GC-FID. Twenty-one constituents, representing 98.4% of the oil were identified. The oil was characterized by high percentages of sesquiterpenes (92.7%) with β-caryophyllene (39.0%) and bicyclogermacrene (25.9%) as the main constituents. This is the first report on the chemical composition of the essential oil from C. leucocephala.