Chemical composition and cytotoxic activity of the leaf essential oil of Eugenia zuchowskiae from Monteverde, Costa Rica

Insights on Juniperus phoenicea Essential Oil as Potential Anti-Proliferative, Anti-Tyrosinase, and Antioxidant Candidate

In this study, the anti-cancer, anti-tyrosinase, and antioxidant activities of essential oils (EOs) of berries and leaves of Juniperus phoenicea grown wild in North of Tunisia were investigated. The EO yields from leaves and berries were 1.69% and 0.45%, respectively. GC-MS analysis revealed that α-pinene is the predominant component in both EOs (44.17 and 83.56%, respectively). Leaves essential oil presented high levels of β-phellandrene (18%) and camphene (15%). The EOs displayed cytotoxic effects against MCF-7 breast cancer cell, HT-29 colon cancer, and the normal cells H9C2 cardiomyoblasts. Leaves oil strongly inhibited colon cell line proliferation (IC50 of 38 µg/mL), while berries essential oil was more potent against breast cancerous cells MCF-7 (IC50 of 60 µg/mL). Interestingly, berries essential oil exhibited high ability to inhibit melanin synthesis by inhibiting enzyme mono and diphenolase activities. Overall, the results suggested that the two oils are significant sources of healthy natural chemicals.

Exploring the Potent Anticancer Activity of Essential Oils and Their Bioactive Compounds: Mechanisms and Prospects for Future Cancer Therapy

Cancer is one of the leading causes of death worldwide, affecting millions of people each year. Fortunately, the last decades have been marked by considerable advances in the field of cancer therapy. Researchers have discovered many natural substances, some of which are isolated from plants that have promising anti-tumor activity. Among these, essential oils (EOs) and their constituents have been widely studied and shown potent anticancer activities, both in vitro and in vivo. However, despite the promising results, the precise mechanisms of action of EOs and their bioactive compounds are still poorly understood. Further research is needed to better understand these mechanisms, as well as their effectiveness and safety in use. Furthermore, the use of EOs as anticancer drugs is complex, as it requires absolute pharmacodynamic specificity and selectivity, as well as an appropriate formulation for effective administration. In this study, we present a synthesis of recent work on the mechanisms of anticancer action of EOs and their bioactive compounds, examining the results of various in vitro and in vivo studies. We also review future research prospects in this exciting field, as well as potential implications for the development of new cancer drugs.

GC/MS Analysis of Essential Oil and Enzyme Inhibitory Activities of Syzygium cumini (Pamposia) Grown in Egypt: Chemical Characterization and Molecular Docking Studies

Syzygium cumini (Pomposia) is a well-known aromatic plant belonging to the family Myrtaceae, and has been reported for its various traditional and pharmacological potentials, such as its antioxidant, antimicrobial, anti-inflammatory, and antidiarrheal properties. The chemical composition of the leaf essential oil via gas chromatography-mass spectrometry (GC/MS) analysis revealed the identification of fifty-three compounds representing about 91.22% of the total oil. The identified oil was predominated by α-pinene (21.09%), followed by β-(E)-ocimene (11.80%), D-limonene (8.08%), β-pinene (7.33%), and α-terpineol (5.38%). The tested oil revealed a moderate cytotoxic effect against human liver cancer cells (HepG2) with an IC₅₀ value of 38.15 ± 2.09 µg/mL. In addition, it effectively inhibited acetylcholinesterase with an IC₅₀ value of 32.9 ± 2.1 µg/mL. Furthermore, it showed inhibitory properties against α-amylase and α-glucosidase with IC₅₀ values of 57.80 ± 3.30 and 274.03 ± 12.37 µg/mL, respectively. The molecular docking studies revealed that (E)-β-caryophyllene, one of the major compounds, achieved the best docking scores of -6.75, -5.61, and -7.75 for acetylcholinesterase, α-amylase, and α-glucosidase, respectively. Thus, it is concluded that S. cumini oil should be considered as a food supplement for the elderly to enhance memory performance and for diabetic patients to control blood glucose.

Liquid and Vapor Phase of Four Conifer-Derived Essential Oils: Comparison of Chemical Compositions and Antimicrobial and Antioxidant Properties

In this study, the chemical composition of the vapor and liquid phase of Pinus cembra L., Pinus mugo Turra, Picea abies L., and Abies Alba M. needles essential oils (EOs) was investigated by Headspace-Gas Chromatography/Mass Spectrometry (HS-GC/MS). In the examined EOs, a total of twenty-eight components were identified, most of which belong to the monoterpenes family. α-Pinene (16.6-44.0%), β-pinene (7.5-44.7%), limonene (9.5-32.5%), and γ-terpinene (0.3-19.7%) were the most abundant components of the liquid phase. Such major compounds were also detected in the vapor phase of all EOs, and α-pinene reached higher relative percentages than in the liquid phase. Then, both the liquid and vapor phases were evaluated in terms of antibacterial activity against three Gram-negative bacteria (Escherichia coli, Pseudomonas fluorescens, and Acinetobacter bohemicus) and two Gram-positive bacteria (Kocuria marina and Bacillus cereus) using a microwell dilution assay, disc diffusion assay, and vapor phase test. The lowest Minimum Inhibitory Concentration (MIC) (13.28 mg/mL) and Minimal Bactericidal Concentration (MBC) (26.56 mg/mL) values, which correspond to the highest antibacterial activities, were reported for P. abies EO against A. bohemicus and for A. alba EO against A. bohemicus and B. cereus. The vapor phase of all the tested EOs was more active than liquid phase, showing the inhibition halos from 41.00 ± 10.15 mm to 80.00 ± 0.00 mm for three bacterial strains (A. bohemicus, K. marina, and B. cereus). Furthermore, antioxidant activities were also investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis (3- ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assays, and a concentration-dependent antioxidant capacity for all EOs was found. P. mugo EO showed the best antioxidant activity than the other Pinaceae EOs. The four Pinaceae EOs could be further investigated for their promising antibacterial and antioxidant properties, and, in particular, α-pinene seems to have interesting possibilities for use as a novel natural antibacterial agent.

Ducrosia ismaelis Asch. essential oil: chemical composition profile and anticancer, antimicrobial and antioxidant potential assessment

The essential oil of Ducrosia ismaelis Asch. (Apiaceae) that grows wild in Saudi Arabia was investigated utilizing gas chromatography (GC), and gas chromatography-mass spectrometry. Fifty constituents were characterized, representing 96.1% of the total oil. The D. ismaelis essential oil (DIEO) was distinguished by a high composition of oxygenated monoterpenes (51.6%). Decanal (40.6%), α-pinene (15.1%) and dodecanal (13.7%) were the fundamental components. Additionally, DIEO was evaluated for its cytotoxic, antibacterial, antifungal and antioxidant activities. DIEO revealed a great cytotoxic effectiveness against the tested cancer cell lines with IC50 values between 66.2 and 137.3 μg/mL particularly against MCF-7 cancer cells. Furthermore, the induction of apoptosis against MCF-7 cells has been asserted using staining assay (annexin VFITC and/or propidium iodide (PI) dyes) and flow cytometry technique. The DIEO possessed a strong antimicrobial activity against Gram-positive bacterial and fungal strains with MIC-values between 0.07 and 0.31 mg/ml. The values of MBC or MFC were almost once higher than those of MIC’s. Moreover, the β-carotene-bleaching and DPPH free radical-scavenging tests showed that DIEO had a moderate activity (68%) as an antioxidant agent in decolouring of the β-carotene at 1.0 mg/mL and a moderate radical scavenging for DPPH (66 and 72%) at 0.50 and 1.0 mg/mL.

Analysis of Chemical Composition and Assessment of Cytotoxic, Antimicrobial, and Antioxidant Activities of the Essential Oil of Meriandra dianthera Growing in Saudi Arabia

The essential oil of Meriandra dianthera (Konig ex Roxb.) Benth. (Synonym: Meriandra bengalensis, Lamiaceae) collected from Saudi Arabia was studied utilizing GC and GC/MS. Forty four constituents were identified, representing 96.8% of the total oil. The M. dianthera essential oil (MDEO) was characterized by a high content of oxygenated monoterpenes (76.2%). Camphor (54.3%) was the major compound in MDEO followed by 1,8-cineole (12.2%) and camphene (10.4%). Moreover, MDEO was assessed for its cytotoxic, antimicrobial, and antioxidant activities. MDEO demonstrated an interesting cytotoxic activity against all cancer cell lines with IC₅₀ values of 83.6 to 91.2 μg/mL, especially against MCF-7 cancer cells. Using labeling with annexin VFITC and/or propidium iodide (PI) dyes and flow cytometer analysis, the apoptosis induction was quantitatively confirmed for MCF-7 cells. The MDEO exhibited a considerable antimicrobial activity against all bacterial and fungal strains with minimum inhibitory concentration (MIC)-values of 0.07 to 1.25 mg/mL. The most sensitive microbial strain was Staphylococcus aureus (MIC: 0.07 mg/mL). Minimum bactericidal concentration (MBC) or minimum fungicidal concentration (MFC) values were determined one time higher than that of MIC’s. Additionally, the MDEO revealed a strong activity for reducing β-carotene bleaching with a total antioxidant value of 72.6% and significant DPPH free radical scavenging activity (78.4%) at the concentration 1000 μg/mL.

Cruzain Inhibitory Activity of Leaf Essential Oils of Neotropical Lauraceae and Essential Oil Components

The leaf essential oils of twenty-three species of Lauraceae from Monteverde, Costa Rica, have been screened for inhibition of the cysteine protease cruzain. Of these, nine showed promising cruzain inhibitory activity (IC50 < 100 μg/mL), six showed marginal activity (IC50, 100–500 μg/mL), and eight were inactive (IC50 > 500 μg/mL). The cruzain inhibitory activities of the essential oils can be attributed to active sesquiterpenoid components as well as synergistic effects between two or more components. The sesquiterpenes α-copaene, β-caryophyllene, α-humulene, and germacrene D are active (IC50 ~5–30 μg/mL) alone, but also show increased activity in combination with other essential oil components.

Les huiles essentielles comme agents anticancéreux : actualité sur le mode d’action

Le cancer est une maladie complexe qui présente un réel problème de santé publique à travers le monde et cause statiquement sept millions de décès chaque année. Au cours des dernières décennies, la thérapie anticancéreuse a connu un réel bouleversement et un foisonnement de découvertes fondamentales. Plusieurs études accumulatives ont révélé l’activité antitumorale des substances naturelles isolées à partir de plantes. Les huiles essentielles (HE) et leurs constituants ont montré des activités anticancéreuses puissantes in vitro et in vivo. Cependant, les mécanismes d’action sont encore peu étudiés et moins connus. Par ailleurs, leur application dans l’industrie pharmaceutique nécessite une spécificité– sélectivité pharmacodynamique absolue. Dans le présent travail, nous présentons une synthèse des travaux réalisés sur les mécanismes d’actions anticancéreuses des HE et leurs composés bioactifs.

A review of Tunisian medicinal plants with anticancer activity

Cancer is a major public health problem in the world. The use of the medicinal plants in cancer prevention and management is frequent in Africa, especially in Tunisia, and it is transmitted from generation to generation within cultures. Many previous studies showed that a wide range of Tunisian medicinal plants exerted cytotoxic and anticancer activity. A comprehensive review was conducted to collect information from scientific journal articles, including indigenous knowledge researches, about Tunisian medicinal plants used for the prevention and management of cancer. The aim of this review article is to provide the reader with information concerning the importance of Tunisian medicinal plants in the prevention and management of cancer and to open the door for the health professionals and scientists working in the field of pharmacology and therapeutics to produce new drug formulations to treat different types of cancer.

Phytochemical composition, anti-inflammatory activity and cytotoxic effects of essential oils from three Pinus spp

Context: Inflammation and cell differentiation lead to a number of severe diseases. In the recent years, various studies focused on the anti-inflammatory and anticancer activity of essential oils (EOs) of numerous plants, including different Pinus species.

Objective: The phytochemical composition, anti-inflammatory and cytotoxic activity of EOs from needles and twigs of Pinus heldreichii Christ (Pinaceae) and P. peuce Griseb., and from needles, twigs and cones of P. mugo Turra were determined.

Materials and methods: For separation and identification of the EOs, gas chromatography/flame ion detector (GC/FID) and GC/mass spectrometry were performed. The amount of secreted IL-6 in a lipopolysaccharide (LPS)-stimulated macrophage model was quantified (concentration of oils: 0.0001–0.2%, 3 h incubation). Cytotoxicity on the cancer cell lines HeLa, CaCo-2 and MCF-7 were determined using a MTT (Thiazolyl Blue Tetrazolium Bromide) assay (concentration of oils: 0.001–0.1%, 24 h incubation).

Results: The most prominent members in the oils include: δ-3-carene, α-pinene and linalool-acetate (P. mugo); α-pinene, β-phellandrene and β-pinene (P. peuce); limonene, α-pinene and (E)-caryophyllene (P. heldreichii). EOs showed significant cytotoxic effects on cancer cell lines (IC₅₀ 0.007 to >0.1%), with a reduction in cell viability with up to 90% at a concentration of 0.1%, and anti-inflammatory activity (IC₅₀ 0.0008–0.02%) with a reduction of IL-6 secretion with up to 60% at a concentration of 0.01%.

Discussion and conclusion: The EOs of needles and twigs from P. peuce and P. heldreichii as well as of needles, twigs and cones of P. mugo can be considered as promising agents for anticancer and anti-inflammatory drugs.

Chemical Profile and in vitro Biological Activities of Essential Oils of Nectandra puberula and N. cuspidata from the Amazon

Essential oils (EO) from leaves and branches of Nectandra puberula Schott (Nees) and from leaves of N. cuspidata Nees & Mart. were obtained by hydrodistillation and their chemical compositions determined by gas chromatography - mass spectrometry (GC-MS). The main compounds identified from N. puberula EO were apiole (22.2%), β-caryophyllene (15.1%), β-pinene (13.3%), germacrene D (8.3%), pogostol (6.6%) and bicyclogermacrene (6.4%) in the leaves; and apiole (28.1%), pogostol (19.8%) and guaiol (11.2%) in the branches. The EO of N. cuspidata leaves showed β-caryophyllene (26.9%), bicyclogermacrene (16.0%) and spathulenol (5.2%) as the main compounds. The EOs were subjected to antibacterial screening and displayed promising activity against Escherichia coli (MIC = 19.5 μg.mL−1). In addition, the EOs were tested for cytotoxic activity against MCF-7 breast tumor cells and the IC50 values were 64.5 ± 1.6 and 117.1 ± 11.9 μg.mL−1 for the leaf EOs of N. puberula and N. cuspidata, respectively.

Composition of the Leaf Essential Oil of Phoebe formosana from Taiwan and its in vitro Cytotoxic, Antibacterial, and Antifungal Activities

The essential oil from the leaves of Phoebe formosana from Taiwan was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. Seventy-one compounds were identified, representing 100% of the oil. The main components identified were α-humulene (16.8%), τ-cadinol (8.9%), α-pinene (8.4%), α-cadinol (8.1%), β-caryophyllene (8.0%), β-phellandrene (6.0%), and β-eudesmol (5.8%). The oil exhibited cytotoxic activity against human lung, liver and oral cancer cells. The active compounds were β-caryophyllene, α-humulene, τ-cadinol, β-eudesmol, and α-cadinol. The antibacterial activity of the oil was tested by the disc diffusion and micro-broth dilution methods against eight bacterial species. The oil exhibited moderate growth suppression against Gram-positive bacteria with inhibition zones of 28 to 36 mm, and MIC values of 250 to 375 μg/mL. The active antibacterial compounds were determined to be τ-cadinol, β-eudesmol, and α-cadinol. The leaf oil displayed excellent antifungal activity with the active compounds determined as α-cadinol, β-eudesmol, τ-cadinol, α-humulene, and β-caryophyllene.

Composition, in vitro Cytotoxicity, and Anti-mildew Activities of the Leaf Essential Oil of Machilus thunbergii from Taiwan

This study investigated the chemical composition, in-vitro cytotoxicity, and anti-mildew fungal activities of the essential oil isolated from the leaf of Machilus thunbergii from Taiwan. The essential oil was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC–FID and GC–MS. Eighty-three compounds were identified, representing 99.8% of the oil. The main components identified were n-decanal (26.6%), β-caryophyllene (15.8%), α-humulene (10.8%), and β-eudesmol (10.5%). The oil exhibited cytotoxic activity against human oral, liver, lung, colon, melanoma, and leukemic cancer cells. The active source compounds were β-caryophyllene, α-humulene, and β-eudesmol. The anti-mildew activity of the leaf oil was also evaluated. Results showed that the leaf oil had excellent anti-mildew activity. For the anti-mildew activity of the leaf oil, the active source compound was determined to be β-eudesmol.

Biological Activity and Chemical Constituents of Essential Oil and Extracts of Murraya microphylla

Murraya microphylla is the most closely related species to M. koenigii (Curry tree). Inspired by the traditional effects of M. koenigii, the antioxidant, anti-inflammatory, and cytotoxic activities of the essential oil and extracts of M. microphylla were evaluated for the first time. The light petroleum and chloroform extracts were found to be able to scavenge DPPH free radicals, inhibit linoleic acid peroxidation, and nitric oxide production, as well as to present cytotoxicity to the human cancer cell lines HepG2, Bel7402, Bel7403, and Hela, but the essential oil only showed moderate activities. Chemical analysis of the active extracts by LC-DAD-MSn indicated that carbazole alkaloids were the main constituents. GC-MS analysis of the essential oil resulted in identification of 91 constituents, representing 96.9% of the total oil, with ( E)-caryophyllene (18.4%) and terpinen-4-ol (12.6%) as the major constituents. These results demonstrate that M. microphylla has similar biological activities, as well as chemical constituents to M. koenigii, and the carbazole alkaloids were disclosed to be the main potential active components. A promising development as a flavor and potential therapeutic agent could thus be predicated for this plant.

Composition, in vitro Cytotoxic, and Antimicrobial Activities of the Flower Essential Oil of Diospyros discolor from Taiwan

This study investigated the chemical composition, in vitro cytotoxic, and antimicrobial activities of the essential oil isolated from the flower of Diospyros discolor from Taiwan. The essential oil was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. Twenty-eight compounds were identified, representing 100% of the oil. The main components identified were (2 Z,6 E)-farnesol (35.0%), α-cadinol (10.9%), ( E)-nerolidol (6.9%), α-humulene (6.0%), τ-cadinol (5.6%), β-caryophyllene (5.3%), and τ-muurolol (5.3%). The oil exhibited cytotoxic activity against human colon, liver, and lung cancer cells. The active compounds were β-caryophyllene, α-humulene, τ-cadinol, τ-muurolol, α-cadinol, and (2 Z,6 E)-farnesol. The antimicrobial activity of the oil was tested by the disc diffusion and micro-broth dilution methods against ten microbial species. The oil exhibited moderate to strong growth suppression against Bacillus cereus, Staphylococcus aureus, S. epidermidis, Escherichia coli, Enterobacter aerogenes, and Candida albicans, with inhibition zones of 40 to 52 mm and MIC values of 31.25–62.5 μg/mL, respectively. For the antimicrobial activities of the oil, the active compounds were determined to be α-cadinol, τ-cadinol, τ-muurolol and (2 Z,6 E)-farnesol.

Genotoxic and Antigenotoxic Assessment of Chios Mastic Oil by the In Vitro Micronucleus Test on Human Lymphocytes and the In Vivo Wing Somatic Test on Drosophila

Chios mastic oil (CMO), the essential oil derived from Pistacia lentiscus (L.) var. chia (Duham), has generated considerable interest because of its antimicrobial, anticancer, antioxidant and other beneficial properties. In the present study, the potential genotoxic activity of CMO as well as its antigenotoxic properties against the mutagenic agent mitomycin-C (MMC) were evaluated by employing the in vitro Cytokinesis Block MicroNucleus (CBMN) assay and the in vivo Somatic Mutation And Recombination Test (SMART). In the in vitro experiments, lymphocytes were treated with 0.01, 0.05 and 0.10% (v/v) of CMO with or without 0.05 μg/ml MMC, while in the in vivo assay Drosophila larvae were fed with 0.05, 0.10, 0.50 and 1.00% (v/v) of CMO with or without 2.50 μg/ml MMC. CMO did not significantly increase the frequency of micronuclei (MN) or total wing spots, indicating lack of mutagenic or recombinogenic activity. However, the in vitro analysis suggested cytotoxic activity of CMO. The simultaneous administration of MMC with CMO did not alter considerably the frequencies of MMC-induced MN and wing spots showing that CMO doesn’t exert antigenotoxic or antirecombinogenic action. Therefore, CMO could be considered as a safe product in terms of genotoxic potential. Even though it could not afford any protection against DNA damage, at least under our experimental conditions, its cytotoxic potential could be of interest.

Antitumor activity of monoterpenes found in essential oils

Cancer is a complex genetic disease that is a major public health problem worldwide, accounting for about 7 million deaths each year. Many anticancer drugs currently used clinically have been isolated from plant species or are based on such substances. Accumulating data has revealed anticancer activity in plant-derived monoterpenes. In this review the antitumor activity of 37 monoterpenes found in essential oils is discussed. Chemical structures, experimental models, and mechanisms of action for bioactive substances are presented.

Composition and in vitro Anticancer Activities of the Leaf Essential Oil of Neolitsea variabillima from Taiwan

This study investigated the chemical composition and in vitro anticancer activities of the essential oil isolated from the leaf of Neolitsea variabillima. The essential oil was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. Sixty-seven compounds were identified, representing 100% of the oil. The main components identified were trans-β-ocimene (13.4%), α-cadinol (10.5%), terpinen-4-ol (9.3%), τ-cadinol (9.2%), β-caryophyllene (8.8%), and sabinene (6.7%). The anticancer activities of oil were evaluated. The results showed that the oil exhibited cytotoxic activity against human oral, liver, lung, colon, melanoma, and leukemic cancer cells. The presence of β-caryophyllene, τ-cadinol, and α-cadinol significantly contributed to the anticancer activities of N. variabillima leaf oil.

Chemical composition and anticancer, antiinflammatory, antioxidant and antimalarial activities of leaves essential oil of Cedrelopsis grevei

The essential oil from Cedrelopsis grevei leaves, an aromatic and medicinal plant from Madagascar, is widely used in folk medicine. Essential oil was characterized by GC-MS and quantified by GC-FID. Sixty-four components were identified. The major constituents were: (E)-β-farnesene (27.61%), δ-cadinene (14.48%), α-copaene (7.65%) and β-elemene (6.96%). The essential oil contained a complex mixture consisting mainly sesquiterpene hydrocarbons (83.42%) and generally sesquiterpenes (98.91%). The essential oil was tested cytotoxic (on human breast cancer cells MCF-7), antimalarial (Plasmodium falciparum), antiinflammatory and antioxidant (ABTS and DPPH assays) activities. C. grevei essential oil was active against MCF-7 cell lines (IC50=21.5 mg/L), against P. falciparum, (IC50=17.5mg/L) and antiinflammatory (IC50=21.33 mg/L). The essential oil exhibited poor antioxidant activity against DPPH (IC50>1000 mg/L) and ABTS (IC50=110 mg/L) assays. A bibliographical review was carried out of all essential oils identified and tested with respect to antiplasmodial, anticancer and antiinflammatory activities. The aim was to establish correlations between the identified compounds and their biological activities (antiplasmodial, anticancer and antiinflammatory). According to the obtained correlations, 1,4-cadinadiene (R(2)=0.61) presented a higher relationship with antimalarial activity. However, only (Z)-β-farnesene (R(2)=0.73) showed a significant correlation for anticancer activity.

Composition and in-vitro CytotoxicActivities of the Leaf Essential Oil of Beilschmiedia erythrophloia from Taiwan

This study investigated the chemical composition and in-vitro cytotoxic activities of the essential oil isolated from the leaf of Beilschmiedia erythrophloia. The essential oil was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. Fifty-five compounds were identified, representing 100% of the oil. The main components identified were β-caryophyllene (22.6%), α-humulene (21.9%), terpinen-4-ol (5.3%), cis-β-ocimene (5.1%), sabinene (5.0%) and limonene (4.5%). The anticancer activities of oil were evaluated. The results showed that the oil exhibited cytotoxic activity against human oral, liver, lung, colon, melanoma, and leukemic cancer cells.

Drugs from the Cloudforest: The Search for New Medicines from Monteverde, Costa Rica

The University of Alabama in Huntsville Natural Products Research Group has been investigating the phytopharmaceutical potential of tropical rainforest higher plants from the Monteverde region of northwestern Costa Rica for the past twenty years. The group has focused primarily on anticancer agents, antimicrobial agents, and antiparasitic agents. This review presents an overview of some of our efforts in natural products drug discovery from Monteverde, Costa Rica.

Essential oils from neotropical Myrtaceae: chemical diversity and biological properties

Myrtaceae family (121 genera, 3800-5800 spp.) is one of the most important families in tropical forests. They are aromatic trees or shrubs, which frequently produce edible fruits. In the neotropics, ca. 1000 species were found. Several members of this family are used in folk medicine, mainly as an antidiarrheal, antimicrobial, antioxidant, cleanser, antirheumatic, and anti-inflammatory agent and to decrease the blood cholesterol. In addition, some fruits are eaten fresh or used to make juices, liqueurs, and sweets very much appreciated by people. The flavor composition of some fruits belonging to the Myrtaceae family has been extensively studied due to their pleasant and intense aromas. Most of the essential oils of neotropical Myrtaceae analyzed so far are characterized by predominance of sesquiterpenes, some with important biological properties. In the present work, chemical and pharmacological studies carried out on neotropical Myrtaceae species are reviewed, based on original articles published since 1980. The uses in folk medicine and chemotaxonomic importance of secondary metabolites are also briefly discussed.

Essential Oil Constituents and Biological Activities of Peristrophe Bicalyculata and Borreria verticillata

Peristrophe bicalyculata (Retz) Nees (Acanthaceae) or ‘The Goddess of Mercy’ and Borreria verticillata (L.) G.F.W. Mey., (Rubiaceae), or ‘Irawo-Ile’ (Yoruba, South-west, Nigeria), are annual herbs, which are poorly exploited. The volatile oils obtained by hydrodistillation in an all glass Clevenger-type apparatus from the plant samples have been investigated by gas chromatography-mass spectrometry (GC-MS). With respect to the oil of P. bicalyculata, β-caryophyllene (33.9%), α-zingiberene (10.4%), germacrene D and globulol (5.0%) were the compounds occurring in abundance. The oil of B. verticillata had an abundance of phytol (56.3%) and 1, 8-cineole (20.4%), with sizeable proportions of α-pinene (7.1%) and p-cymene (4.0%). In addition, the volatile oils displayed promising in-vitro antimicrobial activity against the tested micro-organisms, (MIC 12.5-22.3 μg/mL), while only the oil of P. bicalyculata displayed in-vitro cytotoxicity to MCF-7 (human breast tumor) and MDA-MB-468 (human breast tumor) cells. The present investigation may be the first of its kind for the evaluation of the volatile oil constituents of the studied plants.

Essential oil Composition of Dendropanax Gonatopodus from Monteverde, Costa Rica. An ab Initio Examination of Aromadendrane Sesquiterpenoids

The leaf essential oil of Dendropanax gonatopodus from Monteverde, Costa Rica, has been obtained by hydrodistillation and the chemical composition determined by GC-MS. The major components in the leaf oil were ( E)-2-hexenal (16.9%), terpinolene (14.8%), δ-cadinene (13.5%), ( E)-caryophyllene (9.9%), and α-copaene (7.3%). Minor amounts of the aromadendrane sesquiterpenoids aromadendrene (0.3%), alloaromadendrene (0.3%), spathulenol (0.6%) and globulol (0.6%) were also detected. An ab initio investigation of the aromadendrane sesquiterpenoids has been carried out using both density functional (B3LYP/6-31G*) and post Hartree-Fock (MP2/6-31G**) methods. The calculated relative energies of the aromadendranes belie their relative concentrations generally observed in essential oil compositions.