Thanany B. da Silva

Cytotoxic effect of leaf essential oil of Lippia gracilis Schauer (Verbenaceae)

Medicinal plants are one of the most important sources of drugs used in the pharmaceutical industry. Among traditional medicinal plants, Lippia gracilis Schauer (Verbenaceae) had been used for several medicinal purposes in Brazilian northeastern. In this study, leaf essential oil (EO) of L. gracilis was prepared using hydrodistillation. Followed by GC-MS analysis, its composition was characterized by the presence of thymol (55.50%), as major constituent. The effects of EO on cell proliferation and apoptosis induction were investigated in HepG2 cells. Furthermore, mice bearing Sarcoma 180 tumor cells were used to confirm its in vivo effectiveness. EO and its constituents (thymol, p-cymene, γ-terpinene and myrcene) displayed cytotoxicity to different tumor cell lines. EO treatment caused G1 arrest in HepG2 cells accompanied by the induction of DNA fragmentation without affecting cell membrane integrity. Cell morphology consistent with apoptosis and a remarkable activation of caspase-3 were also observed, suggesting induction of caspase-dependent apoptotic cell death. In vivo antitumor study showed tumor growth inhibition rates of 38.5-41.9%. In conclusion, the tested essential oil of L. gracilis leaves, which has thymol as its major constituent, possesses significant in vitro and in vivo antitumor activity. These data suggest that leaf essential oil of L. gracilis is a potential medicinal resource.

Antitumour properties of the leaf essential oil of Xylopia frutescens Aubl. (Annonaceae)

The aim of this study was to investigate the chemical composition and anticancer effect of the leaf essential oil of Xylopia frutescens in experimental models. The chemical composition of the essential oil was analysed by GC/FID and GC/MS. In vitro cytotoxic activity of the essential oil was determined on cultured tumour cells. In vivo antitumour activity was assessed in Sarcoma 180-bearing mice. The major compounds identified were (E)-caryophyllene (31.48%), bicyclogermacrene (15.13%), germacrene D (9.66%), δ-cadinene (5.44%), viridiflorene (5.09%) and α-copaene (4.35%). In vitro study of the essential oil displayed cytotoxicity on tumour cell lines and showed IC50 values ranging from 24.6 to 40.0 μg/ml for the NCI-H358M and PC-3M cell lines, respectively. In the in vivo antitumour study, tumour growth inhibition rates were 31.0-37.5%. In summary, the essential oil was dominated by sesquiterpene constituents and has some interesting anticancer activity.

Chemical composition of essential oils from Annona vepretorum Mart. and Annona squamosa L. (Annonaceae) leaves and their antimalarial and trypanocidal activities

Here, we describe the trypanocidal and antimalarial activities from essential oils extracted from Annona vepretorum (AVOE) and Annona squamosa (ASOE) (Annonaceae) leaves. The essential oils were obtained by hydrodistillation and analyzed by gas chromatography–mass spectrometry (GC–MS) and GC–flame ionization detection (GC–FID). A total of twenty-one compounds were identified in AVOE and twenty-three in ASOE. The sesquiterpenes are more abundant in the both essential oils. ASOE contained significant quantities of (E)-caryophyllene (27.4%), germacrene D (17.1%) and bicyclogermacrene (10.8%). The major compounds in AVOE were bicyclogermacrene (39.0%), spathulenol (14.0%) and α-phellandrene (11.5%). The essential oils demonstrated potent trypanocidal and antimalarial activities with values of ic50 lower than 20 μg/mL, and a strong inhibition of the proliferation of amastigotes, the clinically relevant forms of Trypanosoma cruzi. In addition, through ultrastructural studies and flow cytometry analysis with trypomastigotes of T. cruzi, we identified significant ultrastructural alterations induced by the essential oils, especially in the cell membrane and mitochondria, which ultimately results in necrotic parasite death.

Evaluation of the anti-inflammatory and antinociceptive effects of the essential oil from leaves of Xylopia laevigata in experimental models.

Xylopia laevigata (Annonaceae) is a medicinal plant used in folk medicine to treat pain and inflammation. Thus, we investigated the possible antioxidant, antinociceptive, and anti-inflammatory effects of X. laevigata leaf essential oil (EOX) in animal models. Our EOX sample showed the presence of γ-muurolene (17.78%), δ-cadinene (12.23%), bicyclogermacrene (7.77%), and α-copaene (7.17%) as main compounds. EOX presented a strong antioxidant potential according to the DPPH, TBARS, and nitrite production tests. Additionally, pretreatment with EOX, in mice, also significantly produced (P < 0.05 or P < 0.001) antinociceptive effect by reduction of nociceptive behavior (in formalin and writhing tests). The EOX showed c-Fos label in the olfactory bulb, piriform cortex, and periaqueductal gray. Acute administration of EOX exhibited a significant (P < 0.01 or P < 0.001) anti-inflammatory profile in the carrageenan-induced peritonitis and by the carrageenan-induced hindpaw edema tests in mice. Our results provide evidence for the use of X. laevigata by traditional medicine practitioners in the management of pain and inflammatory disorders.

Biological activities of the essential oil from the leaves of Xylopia laevigata (Annonaceae)

The essential oil from the leaves of Xylopia laevigata was obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) and GC/flame ionization detector (GC/FID). Thirty-six compounds representing 97.48% of the crude essential oil were identified. The major compounds identified were -muurolene (17.99%), -cadinene (13.45%), germacrene D (9.09%), bicyclogermacrene (7.00%), -copaene (5.98%), and (E)-caryophyllene (5.43%). The biological activities of the essential oil against Trypanosoma cruzi epimastigote forms, yeast, bacteria, Aedes aegypti larvae, antioxidant properties and antiproliferative activity against tumor cell lines were investigated. The essential oil showed trypanocidal activity with IC50 value of 93.9±2.6 μg/mL. For antibacterial and antifungal activities, the best results were observed against Staphylococcus aureus (ATCC14458), Staphylococcus epidermidis (ATCC1228) and Candida tropicalis (ATCC 157), all with a minimal inhibitory concentration value of 100 μg/mL. The essential oil showed antioxidant capacity of 1468.96 μmol of TE/g in the oxygen radical absorbance capacity (ORACFL) assay. The oil showed moderate larvicidal activity with LC50 value of 632.36 μg/mL. The essential oil exhibited potent antiproliferative activity against all cell lines evaluated with total growth inhibition (TGI) value <40 μg/mL, exception for K562 cell line (TGI>250 μg/mL). The highest activity was observed against cell lines of UACC-62, NCI-ADR/RES and NCI-H460, with TGI values of 4.03, 4.26 and 8.37 μg/mL, respectively. For the VERO cell (non-cancer cell line), the TGI value was of 15.94 μg/mL.

Chemical composition and antiparasitic activity of essential oils from leaves of Guatteria friesiana and Guatteria pogonopus (Annonaceae)

Abstract Natural products represent a valuable source for discovery of antiparasitic agents. Here, we describe the antiparasitic activity from essential oils extracted from leaves of Guatteria friesiana (EOGF) and Guatteria pogonopus (EOGP) (Annonaceae). The essential oils were obtained by hydrodistillation and analyzed by GC/MS and GC-FID. The sesquiterpenes are more abundant in both essential oils. G. friesiana are dominated by β-eudesmol (51.9%), γ-eudesmol (18.9%) andα-eudesmol (12.6%). The major compounds identified for EOGP were spathulenol (24.8%), γ-amorphene (14.7%) and germacrene D (11.8%). The essential oils demonstrated potent trypanocidal and antimalarial activities with values of IC50 lower than 41.3 μg/mL. EOGF also inhibits the proliferation of amastigotes. In addition, we identified significant ultrastructural alterations induced by the essential oils, especially in the cell membrane, Golgi complex, endoplasmatic reticulum and mitochondria. The results presented herein reinforce the potential of other members of this family for search of antiparasitic compounds.