Beatriz Helena L. N. Sales Maia

Chemical composition and antimicrobial activity of the essential oils of the Amazon Guatteriopsis species

The essential oils of Guatteriopsis blepharophylla, Guatteriopsis friesiana and Guatteriopsis hispida were obtained by hydrodistillation and analysed by GC and GC/MS. The main compound found in the leaf oil of G. blepharophylla was caryophyllene oxide (1) (69.25%). The leaf oil of G. friesiana contained predominantly beta-eudesmol (2) (51.60%), gamma-eudesmol (3) (23.70%), and alpha-eudesmol (4) (14.56%). The major constituents identified in the leaf of G. hispida were beta-pinene (38.18%), alpha-pinene (30.77%) and (E)-caryophyllene (20.59%). The antimicrobial activity of the essential oils was evaluated against 11 species of microorganisms. The oil of G. friesiana exhibited significant antimicrobial activity for all microorganisms tested, whereas that of G. hispida and G. blepharophyla had potent activity against Rhodococcus equi with MIC of 50 microg mL(-1). The major constituents of each oil were also tested separately, and showed lower activity compared to the oils. Moreover, mixtures of the main constituents, in the same proportions found in G. friesiana and G. hispida oils, did not show the same activity as the original oils.

Attraction of the Fruit-Eating Bat Carollia perspicillata to Piper gaudichaudianum Essential Oil

We performed field tests using mimetic Piper fruits with and without essential oil extracted through hydrodistillation from Piper gaudichaudianum ripe fruits in order to evaluate the role of odor in Carollia perspicillata attraction and capture in mist-nets. During the field tests, 26 C. perspicillata were captured, 21 (80.7%) in nets with the essential oil of P. gaudichaudianum and five (19.3%) in nets without oil. Other bat species, Artibeus spp. (67), which is specialized on fruits of Moraceae, and Sturnira lilium (10), specialized on those of Solanaceae, were also captured, but they exhibited no significant preference for nets with or without oil. We conclude that odor is pre-eminent over visual cues in food location by C. perspicillata in a field situation. Based on the result, we propose the extraction and use of essential oils of chiropterochoric fruits as a useful approach to improve autoecological studies on fruit-eating bats and to promote tropical forest restoration through the attraction of frugivorous bats to degraded areas.

Antimicrobial and antileishmanial activity of essential oil from the leaves of Annona foetida (Annonaceae)

bicyclogermacrene (35.12%), (E)-caryophyllene (14.19%) and α-copaene (8.19%). The antimicrobial and antileishmanial activities were investigated. The oil showed potent antimicrobial activity against Candida albicans and Rhodococcus equi. The oil also showed significant antileishmanial activity, giving the best results against Leishmania guyanensis. A preliminary cytotoxicity assay for this oil was carried out on hamster and mice (Balb/c) peritoneal macrophages. The results obtained were similar to pentamidine and considered not to be cytotoxic to macrophages.

Alkaloids from the Bark of Guatteria hispida and Their Evaluation as Antioxidant and Antimicrobial Agents

Phytochemical investigation of the bark of Guatteria hispida afforded three new alkaloids, 9-methoxy-O-methylmoschatoline (1), 9-methoxyisomoschatoline (2), and isocerasonine (3), along with 10 known alkaloids, 8-oxopseudopalmatine (4), O-methylmoschatoline (5), lysicamine (6), liriodenine (7), 10-methoxyliriodenine (8), nornuciferine (9), anonaine (10), xylopine (11), coreximine (12), and isocoreximine (13). The major compounds, 2, 6, 12, and 13, showed significant antioxidant capacity in the ORAC(FL) assay. Compounds 5, 6, and 7 were active against S. epidermidis and C. dubliniensis, with MIC values in the range 12.5-100 microg mL(-1).

In Vitro Cytotoxic Potential of Essential Oils of Eucalyptus benthamii and Its Related Terpenes on Tumor Cell Lines

Eucalyptus L. is traditionally used for many medicinal purposes. In particular, some Eucalyptus species have currently shown cytotoxic properties. Local Brazilian communities have used leaves of E. benthamii as a herbal remedy for various diseases, including cancer. Considering the lack of available data for supporting this cytotoxic effect, the goal of this paper was to study the in vitro cytotoxic potential of the essential oils from young and adult leaves of E. benthamii and some related terpenes (α-pinene, terpinen-4-ol, and γ-terpinene) on Jurkat, J774A.1 and HeLa cells lines. Regarding the cytotoxic activity based on MTT assay, the essential oils showed improved results than α-pinene and γ-terpinene, particularly for Jurkat and HeLa cell lines. Terpinen-4-ol revealed a cytotoxic effect against Jurkat cells similar to that observed for volatile oils. The results of LDH activity indicated that cytotoxic activity of samples against Jurkat cells probably involved cell death by apoptosis. The decrease of cell DNA content was demonstrated due to inhibition of Jurkat cells proliferation by samples as a result of cytotoxicity. In general, the essential oils from young and adult leaves of E. benthamii presented cytotoxicity against the investigated tumor cell lines which confirms their antitumor potential.

Chemical constituents isolated from the bark of Guatteria blepharophylla (Annonaceae) and their antiproliferative and antimicrobial activities

Phytochemical study of the bark of Guatteria blepharophylla (Mart.) Mart. afforded twelve compounds, namely two sesquiterpenes, caryophyllene oxide (1) and spathulenol (3), one xanthone, lichexanthone (2), a mixture of steroids, β-sitosterol (4), and stigmasterol (5), and seven isoquinoline alkaloids, O-methylmoschatoline (6), lysicamine (7), nornuciferine (8), liriodenine (9), isocoreximine (10), subsessiline (11), and isomoschatoline (12). Their structures were established on the basis of spectroscopic methods. Compounds 1-6, 11 and 12 were reported for the first time in this species. The 13C NMR (nuclear magnetic resonance) data for the compounds 11 and 12 are described for the first time in the literature. The antiproliferative activity against human tumour cell lines and antimicrobial activities were investigated for the major compounds. Compound 9 showed significant activity against cell lines of breast (MCF-7, Michigan Cancer Foundation-7), superior to the positive control doxorubicin. Compound 12 presented antifungal activity similar to the positive control nystatin against Candida albicans.

7,7-Dimethylaporphine alkaloids from the stem of Guatteriopsis friesiana.

Phytochemical investigation of a methanolic extract of the stem of Guatteriopsis friesiana afforded two new 7,7-dimethylaporphine alkaloids, 6,6a-dihydrodemethoxyguadiscine (1) and guatteriopsiscine (3), together with demethoxyguadiscine (2), liriodenine (4), corypalmine (5), and coreximine (6). Their structures were elucidated on the basis of spectroscopic methods (UV, IR, EIMS, HRESIMS, 1D/2D NMR). The absolute configurations of 1 and 3 were determined from the circular dichroism curves. The presence of 7,7-dimethylaporphine alkaloids in this species is important for the chemotaxonomy of Guatteriopsis. Antimicrobial activity of compounds 1-5 was investigated, and 4 showed activity against Rhodococcus equi, with a MIC value of 10 microg x mL(-1).

Antiadherent activity of Schinus terebinthifolius and Croton urucurana extracts on in vitro biofilm formation of Candida albicans and Streptococcus mutans.

OBJECTIVE To evaluate the antiadherent property of crude, methanol and acetate methanol extract fractions from Schinus terebinthifolius and Croton urucurana in hydroalcoholic (HA) and dimethylsulfoxide (DMSO) solvents on in vitro biofilms formed by Streptococcus mutans and Candida albicans strains. DESIGN The minimal concentration of adherence (MICA) was determined to evaluate the antiadherent potential of extracts on the in vitro biofilm formation. The extracts of plants were subjected to thin layer chromatography (TLC) in order to detect what class of compounds was responsible for the antiadherent activity. Data were estimated by analysis of variance (ANOVA) complemented by Tukey test level of significance set at 5%. RESULTS Both plants demonstrated inhibition of S. mutans and C. albicans on in vitro biofilm formation. The biofilms of C. albicans were more efficiently inhibited by the S. terebinthifolius fraction of acetate-methanol and methanol in hydroalcoholic solvents (p<0.05). The S. mutans biofilms adherence was best inhibited by the S. terebinthifolius crude extract and its methanolic fraction, both in hydroalcoholic solvent (p<0.05). TLC of crude extracts and fractions of S. terebinthifolius detected the presence of several active compounds, including phenolic compounds, anthraquinones, terpenoids, and alkaloids. C. urucurana extracts confirmed activity for both microorganisms (p<0.05). However, higher concentrations were needed to achieve antiadherent activity, mainly to inhibit in vitro biofilm formation of C. albicans. CONCLUSION The antiadherent potential of both plants on in vitro biofilms formed by C. albicans and S. mutans were confirmed, suggesting the importance of studies about these extracts for therapeutic prevention of oral diseases associated with oral biofilms.

Composition of essential oils and secretory structures of Baccharis anomala, B. megapotamica and B. ochracea

The chemical composition of the essential oils and the anatomical structures of the aerial parts from Baccharis anomala, B. megapotamica and B. ochracea growing in Brazil were studied. The volatile constituents isolated by hydrodistillation were analyzed by gas chromatograph coupled to a mass spectrometer detector (GC-MSD) and gas chromatograph coupled to a flame ionization detector (GC-FID). The botanical material was fixed, sectioned and prepared according to light and scanning microtechniques. The essential oil from B. anomala yielded 0.18% and showed α-acorenol (16.0%), spathulenol (13.3%) and caryophyllene oxide (12.1%) as the main components. Spathulenol (28.0% and 37.1%) and caryophyllene oxide (20.4% and 30.8%) represented the major constituents of the essential oils from B. megapotamica (yield = 0.17%) and B. ochracea (yield = 0.18%), respectively. The leaves and stems of these Baccharis species showed non-glandular trichomes and secretory ducts. Glandular trichomes were also found on the vegetative aerial parts of B. megapotamica

Volatile Oil of Psidium cattleianum Sabine from the Brazilian Atlantic Forest

Abstract The essential oil obtained by hydrodistillation of fresh leaves of Psidium cattleianum Sabine, collected in the Atlantic Forest in southeastern Brazil, was analyzed by GC and GC/MS. The oil had the main constituents α-thujene (25.2%), 1,8-cineole (16.4%) and β-caryophyllene (10.2%).