Carmen L. Queiroga

Evaluation of the antiulcerogenic activity of friedelan-3β-ol and friedelin isolated from Maytenus ilicifolia (Celastraceae)

An easy methodology for triterpene isolation is shown. Evaluation in rats for antiulcer activity of friedelan-3beta-ol 1 and friedelin 2. The two triterpenes isolated from the leaves of Maytenus ilicifolia, did not decrease gastric ulcers when tested on indometacine induced ulcer model in rats.

Evaluation of paraffins biodegradation and biosurfactant production by Bacillus subtilis in the presence of crude oil

Bacillus subtilis experiments for surface tension evaluation were accomplished with culture medium containing 0.4% nitrate ions and 4% glucose basic nutrient in the presence of crude oil. Surfactin production was observed by surface tension reduction of the culture broth. Surfactin was isolated from Bacillus subtilis fermented broth, by acid-precipitation followed by extraction with chloroform-methanol. Evaluation of the linear alkanes composition was performed by capillary gas chromatography. We observed a significant reduction of the surface tension of the fermented broth indicating that the biosurfactant production was not inhibited by the crude oil presence, and that the light paraffins might have been consumed.

Chemical constituents of the volatile oil from leaves of Annona coriacea and in vitro antiprotozoal activity

The essential oil of the leaves from Annona coriacea Mart., Annonaceae, was extracted by hydrodistillation in a Clevenger apparatus and analyzed by GC/MS and GC/FID. The oil yield was 0.05% m/m. Sixty compounds were identified, in a complex mixture of sesquiterpenes (76.7%), monoterpenes (20.0%) and other constituents (3.3%). Bicyclogermacrene was its major compound (39.8%) followed by other sesquiterpenes. Most of the monoterpenes were in low concentration (<1%). Only β-pinene and pseudolimonene presented the highest level of 1.6%. The volatile oil presented anti-leishmanial and trypanocidal activity against promastigotes of four species of Leishmania and trypomastigotes of Trypanosoma cruzi, showing to be more active against Leishmania (L.) chagasi (IC50 39.93 µ g/mL) (95% CI 28.00-56.95 µ g/mL).

Three new oxygenated cadinanes from Baccharis species

Abstract Synthesis of several (±)-[4S-(4β,4aβ,8aα)]-1,6-dimethyl-4-(1 methylethyl)-1,2,3,4,5,8,8a-octahydro-1-naphthalenol derivatives (cadinanol derivatives) provided the necessary evidence for the identification of three novel cadinane derivatives [(±)-[1S-(1β, 4β, 4aβ, 8aα)]-1,6-dimethyl-4-(1-methylethyl)-1,2,3,4,4a,5,8,8a-octahydro-1-naphthalenol 11a, (±)-[1S-(1β, 4β, 4aβ, 4aβ, 6α, 7α, 8aα)]-6, 7-epoxide-1,6-dimethyl-4-(1-methylethyl)-1,2,3,4,4a,5,6,7,8,8a-decahydro-1- naphthalenol 14 and (±)-[1S-(1β,4β,4aβ,6β,8aα)]-1,6-dimethyl-4-(1-methylethyl-1,2,3,4,4a,5,6,7,8,8a-decahydro-1,6-naphthalenediol 15] detected, in the essential oils of, B. platipoda. Compound 14 was also detected in B. tridentata. The synthetic compounds were characterized by one and two dimensional 1H and 13C NMR. The identification was obtained by coinjection of the oils with the synthetic standards and fragmentation pattern comparison.

Wood typification by Venturi easy ambient sonic spray ionization mass spectrometry: the case of the endangered Mahogany tree.

Venturi easy ambient sonic spray ionization mass spectrometry in both its liquid (V(L) -EASI-MS) and solid sample modes (V(S) -EASI-MS) is shown to provide nearly immediate and secure typification of woods, as demonstrated for Mahogany, an endangered and most valuable type of tropical wood. This reddish wood displays unique phytochemical markers (phragmalin-type limonoids) which are rapidly detected from the wood surface by V(S) -EASI-MS or from a simple methanol extract of a tiny wood chip by V(L) -EASI-MS. Unique profiles were obtained for Mahogany (Swietenia macrophylla) whereas genuine samples of six other similar types of woods, which are commonly falsified by artificial coloring and commercialized as Mahogany, display also typical but dissimilar pythochemical profiles as compared to that of the authentic wood. Variable and atypical chemical profiles were observed for artificially colored woods. Secure chemical characterization via V(S) -EASI-MS or V(s) -EASI-MS fingerprints of Mahogany and other types of woods with similar appearance should help to control the illegal logging and trade of this and other endangered woods and their falsification, and to create certified standards.

Anticholinesterase activity evaluation of alkaloids and coumarin from stems of Conchocarpus fontanesianus

Conchocarpus fontanesianus (A. St.-Hill.) Kallunki & Pirani, Rutaceae, popularly known as pitaguara, is a native and endemic tree from Sao Paulo and Rio de Janeiro States, Brazil. Based in the information that anticholinesterasic derivatives could act as new prototypes to treatment of Alzheimer disease, this work describes the fractionation guided by evaluation of the anticholinesterase activity of the ethanolic stems extract from C. fontanesianus. This procedure afforded the alkaloids dictamnine (1), γ-fagarine (2), skimianine (3), and 2-phenyl-1-methyl-4-quinolone (4), as well as the coumarin marmesin (5).

COMPARISON OF THE CHEMICAL COMPOSITION OF THE ESSENTIAL OIL AND THE WATER SOLUBLE OIL OF BACCHARIS DRACUNCULIFOLIA DC (ASTERACEAE)

Abstract This study aimed to evaluate the chemical composition of Baccharis dracunculifolia essential oil and the water soluble oil obtained by steam distillation that were analyzed by GC and GC/MS. In the first hour of distillation B. dracunculifolia aerial parts yielded 0.08% oil and in the second hour, 0.27%. The oil recovered from the distillate water yielded 0.18 g/L in the first hour and 0.44 g/L in the second hour of distillation. The main volatile compounds identified in the distillate water were aromatic compounds and sesquiterpene alcohols.

Study of the Variation of the Composition of the Essential Oil of Leaves and Flowers of Achyrocline alata (D.C.) Along a Period of the Day

Abstract Leaves and flowers of Achyrocline alata were picked in an experimental garden throughout the period of 7 AM until 2 PM, in hourly intervals. The leaf and flower oils were obtained by hydrodistillation. Analyses of the oils by GC/MS reveals that the main components of the leaf oil varied as follows: α-pinene (1.7–7.6%), 1-octen-3-ol (1.7–5.6%), 1,8-cineole (0.4–5.1%), β-caryophyllene (14.6–16.7%), α-humulene (20.6–25.1%) and bicyclogermacrene (7.3–12.4%). The flower oil also varied—α-pinene (5.4–21.9%), 1-octen-3-ol (8.0–11.6%), 1, 8-cineole (7.3–10.9%), β-caryophyllene (12.0–17.5%), α-humulene (17.2–22.8%) and bicyclogermacrene (5.8–8.3%)—throughout the 8-h period.

Chemical composition and biological activity of Eupatorium intermedium essential oil

Abstract This article reports a study on the extraction and evaluation of essential oil obtained from dried flowers of Eupatorium intermedium, a plant native to southern Brazil that belongs to the Asteraceae family. The hydrodistillation achieved a maximum yield of 1.01 wt% of essential oil. Regarding the chemical composition, by a qualitative analysis, the identified substances were α-pinene, sabinene, β-pinene, limonene, caryophyllene (E), germacrene D, spathulenol and caryophyllene oxide. The antioxidant activity of the essential oil obtained was evaluated using the DPPH method, phosphomolybdenum reducing method and total phenolic content. The total phenolic content was 4.26 mg GAE/g of oil. The antioxidant activity obtained by the DPPH method was 0.82 wt%, at a concentration of 250 mg/mL. The antioxidant activity obtained through the reduction of the phosphomolybdenum complex was 1154.69 mg α-tocopherol/g of oil. Antibacterial activity assays were performed using the agar well method. The oil presented antibacterial effects against the Gram-positive bacteria tested.

High-speed countercurrent chromatography as a tool to isolate nerolidol from the Baccharis dracunculifolia volatile oil

Baccharis dracunculifolia is a shrub native to Brazil and an important botanical source for propolis production. The essential oil from the leaves of B. dracunculifolia DC (Asteraceae), popularly known as broom oil, presents pharmacological activities and is a raw material in the perfumery and cosmetics industries. The isolation of its major constituent, nerolidol, to a high purity (92.5–93.7%) was possible through the countercurrent chromatography technique. The countercurrent chromatography biphasic solvent system chosen was a mixture of hexane:methanol:water (5:4:1, v/v/v). Isocratic elution was conducted in a tail-to-head manner.