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Ageratina dendroides is an aromatic species native to Ecuador. In this study, the chemical composition, enantiomeric distribution, and antifungal, antibacterial, antioxidant, and anticholinesterase activities of the essential oil isolated from aerial parts of Ageratina dendroides were determined. The quantitative chemical composition was determined using gas chromatography equipped with a flame ionization detector. The qualitative chemical composition was determined using gas chromatography coupled with mass spectrometry. The enantiomeric distribution was determined using an enantioselective chromatographic column. A broth microdilution method was used to determine the antibacterial activity. This antibacterial activity was tested against three Gram-negative bacilli bacteria and three Gram-positive cocci bacteria. The antifungal activity was tested against two fungi, a fungus, and a yeast. The antioxidant activity was determined using the ABTS (2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)) method and DPPH (2,2-diphenyl-1-picrylhydrazyl) method. The anticholinesterase activity was analyzed using the spectrophotometric method. Sixty-eight volatile compounds were identified in the essential oil. These compounds represent 99.49% of the total composition. In terms of the number of compounds and their relative abundance, the most representative group was sesquiterpene hydrocarbons, with thirty-four compounds and an abundance of 49.22%. The main constituents were found to be andro encecalinol (14.41 ± 1.26%), germacrene D (8.86 ± 1.06%), amorpha-4,9-dien-14-al (7.68 ± 0.70%), β-sesquiphellandrene (7.01 ± 1.49%), α-muurolol (5.89 ± 0.93%), and 7-epi-α-selinene (5.68 ± 0.53%). Five pairs of enantiomers were identified in the essential oil of Ageratina dendroides. The essential oil did not report antimicrobial activity at the maximum concentration tested (MIC > 4000 µg/mL) against any of the microorganisms tested. The antioxidant activity of the essential oil was strong in the ABTS method, with an SC50 of 33.2 ± 1.4 µg/mL. Additionally, the Ageratina dendroides essential oil reported moderate anticholinesterase activity, with an IC50 of 297.8 ± 1.03 µg/mL. [ABSTRACT FROM AUTHOR]

Essential oils are a complex mixture of aromatic substances whose pharmacological actions, including antimicrobial, antioxidant, anticancer, and anti-inflammatory activities, have been widely reported. This study aimed to evaluate the anti-Candida and dermal anti-inflammatory activity of essential oils from native and cultivated Ecuadorian plants. Essential oils from Bursera graveolens, Dacryodes peruviana, Mespilodaphne quixos, and Melaleuca armillaris were isolated by hydrodistillation and were characterized physically and chemically. Its tolerance was analyzed by in vitro and in vivo studies. The antifungal activity was studied against Candida albicans, Candida glabrata, and Candida parapsilosis, whereas the anti-inflammatory effect was evaluated by a mouse ear edema model. The main compounds were limonene, α-phellandrene, (E)-methyl cinnamate, and 1,8-cineole, respectively. All essential oils showed high tolerability for skin application, antifungal activity against the three Candida strains, and anti-inflammatory efficacy by decreasing edema and overexpression of pro-inflammatory cytokines. Dacryodes peruviana essential oil showed the highest antifungal activity. On the other hand, Dacryodes peruviana and Melaleuca armillaris showed the greatest anti-inflammatory potential, decreasing edema by 53.3% and 65.25%, respectively, and inhibiting the overexpression of TNF-α, IL-8, IL-17A, and IL-23. The results suggest that these essential oils could be used as alternative therapies in the treatment of both cutaneous candidiasis and dermal inflammation. [ABSTRACT FROM AUTHOR]

The species Morella pubescens, commonly known as wax laurel, is a tree belonging to the Myricaceae family that can be found from Costa Rica to Bolivia. In this study, the chemical composition, enantiomeric distribution, and biological activity of essential oil isolated from the leaves of this species was determined. Hydrodistillation was used to isolate the essential oil (EO). Gas chromatography coupled with mass spectrometry was used to determine the qualitative composition, gas chromatography equipped with a flame ionization detector was used to determine quantitative composition, and gas chromatography on an enantioselective column was used to determine enantiomeric distribution. The broth microdilution method was employed to assess the antibacterial capacity of the essential oil against seven opportunistic microorganisms, including three Gram-positive cocci bacteria, a Gram-positive bacilli bacterium and three Gram-negative bacilli bacteria. 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radical cation and 2,2-diphenyl-1-picrylhydryl free radical were used as reagents to determine the antioxidant activity of essential oil. The spectrophotometric method was used to analyze the acetylcholinesterase inhibitory effect of the essential oil. The extraction method afforded a low yield of around 0.076 ± 0.008% (v/w). Fifty-eight chemical compounds, which represent 97.9% of the total composition, were identified in the essential oil. Sesquiterpene hydrocarbons were the most representative group with 24 compounds (67.8%). The principal constituents were (E)-caryophyllene (27.5 ± 1.3%), limonene (11.8 ± 0.6%), δ-selinene (9.1 ± 0.2%), β-selinene (8.0 ± 0.2%), selina-3,7(11)-diene (5.3 ± 0.2%) and germacrene B (5.0 ± 0.5%). Three pairs of enantiomers were identified in the essential oil of Morella pubescens. Essential oil presented strong activity against the bacterium Enterococcus faecium (ATCC 27270) with an MIC of 250 μg/mL. The antioxidant activity of essential oil was very strong in the ABTS method with an SC50 of 46.4 ± 1.0 µg/mL and was strong in the DPPH method with an SC50 of 237.1 ± 1.8 µg/mL. Additionally, the essential oil reported strong anticholinesterase activity with an IC50 of 133.5 ± 1.06 µg/mL. [ABSTRACT FROM AUTHOR]

The species Peperomia inaequalifolia, commonly known as congona, is a succulent herbaceous plant belonging to the Piperaceae family, which is used for different purposes in traditional medicine. In this study, the chemical composition, enantiomeric distribution, and biological activity of essential oil isolated from the leaves of this species was determined. Hydrodistillation was used to isolate the essential oil. Gas chromatography coupled to mass spectrometry was used to determine the qualitative composition, a gas chromatograph equipped with a flame ionization detector was used to determine quantitative composition, and gas chromatography on an enantioselective column was used to determine enantiomeric distribution. Antibacterial activity was determined using the broth microdilution method, for which we used three Gram-positive cocci bacteria, a Gram-positive bacilli bacterium, and three Gram-negative bacilli bacteria. 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical cations and 2,2-diphenyl-1-picrylhydryl (DPPH) radicals were used as reagents for determining the antioxidant activity of the essential oil. The spectrophotometric method was used to analyze the acetylcholinesterase inhibitory effect of the essential oil. The yield of leaves in essential oil was 0.16 ± 0.01% (v/w). Forty-three chemical compounds were identified in the essential oil, which represent 97.46% of the total composition. Sesquiterpene hydrocarbons were the most representative group, with 24 compounds (21.63%). The principal constituents were found to be elemicin (27.44 ± 1.35%), bisabolol <α-> (17.76 ± 1.38), myristicin (15.45 ± 0.86), methyl eugenol (6.22 ± 0.24), viridiflorene (6.81 ± 0.10), and safrole (6.68 ± 0.23). Three pairs of enantiomers were identified in the essential oil of Peperomia inaequalifolia. Essential oil presented a minimum inhibitory concentration (MIC) of 4000 μg/mL against Enterococcus faecalis, Enterococcus faecium, Staphylococcus aureus, Listeria monocytogenes, and Escherichia coli. The antioxidant activity of the essential oil was strong according to the DPPH and ABTS methods, with a half radical scavenging capacity (SC50) of 293.76 ± 3.12 µg/mL and 226.86 ± 0.05 µg/mL, respectively. Additionally, the essential oil reported moderate anticholinesterase activity, with an IC50 of 43.93 ± 1.05 µg/mL. [ABSTRACT FROM AUTHOR]

Bixa orellana is a native and cultivated species of Ecuador commonly known as achiote (annatto), this species is very versatile with a wide variety of uses and applications of its leaves, fruits and seeds. In this study, the chemical composition, enantiomeric distribution and biological activity of essential oil isolated from the leaves of Bixa orellana were determined. Hydrodistillation was used to isolate the essential oil. Gas chromatography coupled with mass spectrometry was used to determine the qualitative composition, a gas chromatograph equipped with a flame ionization detector was used to determine quantitative composition and gas chromatography on an enantioselective column was used to determine enantiomeric distribution. Antibacterial activity was determined using the broth microdilution method, for which we used three Gram-positive cocci bacteria, a Gram-positive bacilli bacterium and three Gram-negative bacilli bacteria. 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic (ABTS) acid radical cation and 2,2-diphenyl-1-picrylhydryl (DPPH) free radical were used as reagents for determining the antioxidant activity of the essential oil. The spectrophotometric method was used to analyze acetylcholinesterase inhibitory effect of the essential oil. The yield of leaves in essential oil was 0.13 ± 0.01% (v/w). A total of 56 chemical compounds, which represent 99.25% of the total composition, were identified in the essential oil. Sesquiterpene hydrocarbons were the most representative group in number of compounds and relative abundance with 31 compounds and 69.06%, respectively. The principal constituents were found to germacrene D (17.87 ± 1.20%), bicyclogermacrene (14.27 ± 0.97%), caryophyllene < (E)– > (8.56 ± 1.24%) and pinene <α-> (6.34 ± 0.13%). Six pairs of enantiomers were identified in the essential oil of Bixa orellana. The essential oil presented strong activity against the Enterococcus faecium (ATCC 27270) with an MIC of 250 μg/mL and weak activity against Enterococcus faecalis (ATCC 19433) and Staphylococcus aureus (ATCC 25923) with an MIC of 1000 μg/mL. The antioxidant activity of the essential oil was strong according to ABTS methods with a SC50 of 61.49 ± 0.04 µg/mL and was moderate in DPPH with a SC50 of 224.24 ± 6,4 µg/mL. Additionally, the essential oil reported moderate anticholinesterase activity with an IC50 of 39.45 ± 1.06 µg/mL. [ABSTRACT FROM AUTHOR]

Myrcianthes discolor, an aromatic native tree from southern Ecuador, was collected to determine the chemical composition and the biological activity of its essential oil (EO). The EO was obtained by steam-distillation and analyzed by gas chromatography coupled to a mass and a FID detector (GC-MS and GC-FID) and a non-polar DB5-MS column. Enantioselective GC-MS analysis was performed in a chiral capillary column. The antimicrobial, antioxidant, and anticholinesterase potency of the EO was carried out by the broth microdilution method, radical scavenging assays using 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, and by measuring the inhibition of the acetylcholinesterase (AChE) enzyme. A total of 58 chemical compounds were identified, corresponding to 94.80% of the EO composition. Sesquiterpenes hydrocarbons represented more than 75% of the composition. The main compounds detected were E-caryophyllene with 29.40 ± 0.21%, bicyclogermacrene with 7.45 ± 0.16%, β-elemene with 6.93 ± 0.499%, α-cubebene with 6.06 ± 0.053%, α-humulene with 3.96 ± 0.023%, and δ-cadinene with 3.02 ± 0.002%. The enantiomeric analysis revealed the occurrence of two pairs of pure enantiomers, (−)-β-pinene and (−)-α-phellandrene. The EO exerted a strong inhibitory effect against AChE with an IC50 value of 6.68 ± 1.07 µg/mL and a moderate antiradical effect with a SC50 value of 144.93 ± 0.17 µg/mL for the ABTS radical and a weak or null effect for DPPH (3599.6 ± 0.32 µg/mL). In addition, a strong antibacterial effect against Enterococcus faecium was observed with a MIC of 62.5 μg/mL and Enterococcus faecalis with a MIC of 125 μg/mL. To the best of our knowledge, this is the first report of the chemical composition and biological profile of the EO of M. discolor, and its strong inhibitory effect over AChE and against two Gram-positive pathogenic bacteria, which encourage us to propose further studies to validate its pharmacological potential. [ABSTRACT FROM AUTHOR]

Siparuna muricata is an aromatic native shrub or tree from Ecuador known as "limoncillo" or "limón de la sierra" due to its citrus odor. In this study, the chemical composition and biological activity of essential oil from the leaves and fruits of this species was determined. The essential oil was isolated by subjected to hydrodistillation. The chemical composition was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to mass spectrometry. The enantiomeric distribution was determined by gas chromatography using an enantioselective column. The antimicrobial activity against three Gram-positive bacteria, two Gram-negative bacteria and two fungi was determined by the broth microdilution method. The antioxidant activity was analyzed using the 2,2-diphenyl-1-picrylhydryl free radical and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radical cation scavenging activity of essential oil. The acetylcholinesterase inhibitory effect of the essential oil was measured using a spectrophotometric method. The yield was 1.2 ± 0.1 mL/kg for leaves and 1.8 ± 0.2 mL/kg for fruits. A total of 51 compounds were identified in the leaves of the essential oil and 41 in the fruits. In both cases, the chemical compositions were dominated by the group of monoterpene hydrocarbons compounds. The main compound was α-pinene with 23.22 ± 1.03% in essential oil of the leaves and limonene with 24.92 ± 1.20% in the fruits. In both essential oils, five pairs of enantiomers with different enantiomeric excesses were identified. The essential oil of limoncillo leaves presented a strong activity against the fungus Aspergillus niger (ATTC 10231) and Gram-positive bacterium Enterococcus faecium (ATCC 27270) with a MIC of 250 μg/mL and 500 μg/mL, respectively. The essential oil from fruits and leaves of Siparuna muricata presented a moderate antioxidant activity with the ABTS method with a SC50 of 775.3 ± 1.3 µg/mL and 963.3 ± 1.6 µg/mL, respectively. Additionally, the leaves essential oil reported an IC50 value of 52.98 ± 1.04 µg/mL and the fruits essential oil an IC50 value of 98.84 ± 1.04 µg/mL, which can be considered a very strong anticholinesterase activity. [ABSTRACT FROM AUTHOR]

Essential oils are natural aromatic substances that contain complex mixtures of many volatile compounds frequently used in pharmaceutical and cosmetic industries. Dacryodes peruviana (Loes.) H.J. Lam is a native species from Ecuador whose anti-inflammatory activity has not been previously reported, thus the aim of this study was to evaluate the anti-inflammatory activity of D. peruviana essential oil. To that end, essential oil from D. peruviana fruits was isolated by hydrodistillation and characterized physically and chemically. The tolerance of the essential oil was analyzed by cytotoxicity studies using human keratinocytes. The anti-inflammatory activity was evaluated by an arachidonic acid-induced edema model in mouse ear. The predominant compounds in D. peruviana essential oil were α-phellandrene, limonene, and α-pinene, with the three compounds reaching approximately 83% of the total composition. Tolerance studies showed high biocompatibility of this essential oil with human keratinocytes. In vivo studies demonstrated a moisturizing effect and an alleviation of several events occurred during the inflammatory process after topical treatment with D. peruviana essential oil such as decline in skin edema; reduction in leukocytic infiltrate; and decrease in inflammatory cytokines TNFα, IL-8, IL-17A, and IL-23. Therefore, this essential oil could be an attractive treatment for skin inflammation. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the chemical composition, enantiomeric distribution and the biological profile of Hedyosmum strigosum essential oil (EO). The antioxidant properties and anticholinesterase effect were measured by spectroscopic methods and antimicrobial potency assessed against 8 bacteria and two fungi. H. strigosum is a native shrub, particularly found in Ecuador and Colombia at 2000 to 3500 m a.s.l. Chemical composition was determined by GC-MS and GC-FID. A total of 44 compounds were detected, representing more than 92% of the EO composition. The main compounds were thymol (24.35, 22.48%), α-phellandrene (12.15, 13.93%), thymol acetate (6.59, 9.39%) and linalool (8.73, 5.82%), accounting for more than 51% of the EO. The enantioselective analysis revealed the presence of 5 pure enantiomers and 3 more as a racemic mixture. The EO exerted a strong antioxidant capacity, determined by ABTS assay, with a SC50 of 25.53 µg/mL and a strong and specific antimicrobial effect against Campylobacter jejuni with a MIC value of 125 µg/mL. A moderate acetylcholinesterase inhibitory effect was also observed with an IC50 value of 137.6 µg/mL. To the best of our knowledge this is the first report of the chemical composition and biological profile of H. strigosum EO. [ABSTRACT FROM AUTHOR]

The aim of this study was to extract and identify the chemical compounds of Diplosthephium juniperinum essential oil (EO) from Ecuador and to assess its anticholinesterase and antioxidant properties. The EO chemical composition was determined by GC–MS. A total of 74 constituents of EO were identified, representing 97.27% in DB-5ms and 96.06% in HP-INNOWax of the total EO. The major constituents (>4.50%) identified were: α-pinene (21.52, 22.04%), geranyl acetate (10.54, 7.78%), silphiper-fol-5-ene (8.67, 7.38%), α-copaene (8.26, 8.18%), 7-epi-silphiperfol-5-ene (4.93, 5.95%), and germacrene D (4.91, 6.00%). Enantioselective analysis of the volatile fraction of D. juniperinum showed: (+)-α-pinene as a pure enantiomer and 5 pairs of enantiomeric compounds. Among them, (−)-β-Pinene and (−)-Germacrene D presented a high enantiomeric excess of 93.23 and 84.62%, respectively, while (−)-α-Thujene, (−)-Sabinene and (S)-4-Terpineol with a lower enantiomeric excess of 56.34, 47.84 and 43.11%, respectively. A moderate inhibitory effect was observed for Acetylcholinesterase (AChE) and Butyrylcholinesterase (BuChE) enzymes with IC50 values of 67.20 ± 7.10 and 89.00 ± 9.90 µg/mL, respectively. A lower antioxidant potential was observed for the EO measured through DPPH and ABTS radical scavenging assays with SC50 values of 127.03 and >1000 µg/mL, respectively. To the best of our knowledge, this is the first report of the chemical composition, enantiomeric distribution and, anticholinesterase and antioxidant potential of the EO of D. juniperinum. As future perspective, further in-vivo studies could be conducted to confirm the anticholinesterase potential of the EO. [ABSTRACT FROM AUTHOR]

In the present research, the essential oil from Piper ecuadorense was analysed by GC/MS and GC/FID techniques. A total of forty-four chemical compounds were identified which represent 98.65% of the essential oil composition. The main compounds were bicyclogermacrene (12.98%), 3-thujopsanone (11.59%), α-phellandrene (6.89%), (E)-nerolidol (6.88%), δ-elemene (6.83%) and shyobunol (5.79%). The essential oil from P. ecuadorense exerted a strong activity against Gram-positive bacterium Staphylococcus aureus (ATCC 25923) with an MIC of 250 μg/mL, and a very strong activity against Trichophyton rubrum (ATCC 28188) and Trichophyton mentagrophytes (ATCC 28185) with an MIC of 62.5 μg/mL in both cases. The antioxidant activity of essential oil was explored using DPPH and ABTS method, through ABTS assay. The oils showed an IC50 of 1.81 ± 0.09 mg/mL. This is the first report on the chemical composition and biological activity of essential oil from this species. [ABSTRACT FROM AUTHOR]

In the present research, essential oil from Ageratina dendroides (Spreng.) R.M. King & H. Rob. and Gynoxys verrucosa Wedd. collected of Ecuador were investigated. The isolation of the essential oil was carried out by hydrodistillation and the chemical composition is determined by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detector (GC-FID). In the two species a total of sixty-two volatile compounds were identified, which represent between 98.61 - 99.17 % of the total chemical composition. The main components were germacrene D (29.92 ± 0.68 %), δ-cadinene (9.31 ± 0.11 %) and cis-cadina-1,4-diene (5.48 ± 0.04 %) in the essential oil of Ageratina dendroides, and α-zingiberene (45.57 ± 1.66 %), α-amorphene (11.12 ± 0.24 %), ρ-cymene (15.23 ± 0.10 %) and α-phellandrene (11.72 ± 0.15 %) in the oil of Gynoxys verrucosa. Yield and physical properties of essential oil are also reported. This is the first report on volatile compounds for this species. [ABSTRACT FROM AUTHOR]

Phytochemical study of P. lanceifoluim, used in the traditional medicine in the South of Ecuador, resulted in the isolation of one flavone called Sakuranetin (1), two benzoic derivative acid knows called: lanceaefolic acid methyl ester (2), and cyclolanceaefolic acid methyl ester (3). The structures of compounds were established by means of 1H- and 13C-NMR and MS data, and compared with literature data. The essential oils were obtained by hydrodistillation and then analysed by gas chromatography/flame ionization detector (GC/FID) and gas chromatography/mass spectrometry (GC/MS), a total of 35 constituents were identified, representing the 97.3% of the chemical composition. Safrole was the most abundant compound in the plant with 48.3%. Monoterpene hydrocarbons and oxygenated monoterpenes are the most important groups of compounds in the essential oil of P. lanceifolium, this oil exhibited a moderate antibacterial effect against Klebsiella pneumoniae (ATCC 9997). [ABSTRACT FROM AUTHOR]

In the present research, the essential oil of Sarcorhachis sydowii Trel was analyzed. The chemical composition was performed by GC/MS and GC/FID techniques. A total of 42 chemical compounds were identified which represent 98.53 % of the essential oil composition. The main compounds were (E)-caryophyllene (25.07 %). α-humulene (10.48 %), α-selinene (7.58 %), β-selinene (6.08 %) and α-phellandrene (5.37 %). In addition, a low amount of safrole (0.74 %) was identified. The antimicrobial activity and antifungal activity of the oil were assayed against two Gram-positive bacteria, five Gram-negative bacteria and two fungi. The essential oil from S. sydowii Trel exerted strong activity against Trichophyton rubrum (ATCC 28188) and Trichophyton mentagrophytes (ATCC 28185) with a MIC of 500 μg/mL. However, the EO did not show activity against any bacteria at the maximum concentration tested (1000 μg/mL). The antioxidant activity of the essential oil was explored using DPPH and ABTS methods, and the oils showed an IC50 of 950 μg/mL and 800 μg/mL, respectively. This is the first report on the chemical composition and biological activity of essential oil from this species. [ABSTRACT FROM AUTHOR]

In the present research the essential oil from aerial parts of Gnaphalium elegans was extracted by hydrodistillation and analyzed by Gas Chromatography coupled to mass spectroscopy (GC/MS) and Gas Chromatography flame ionization detector (GC-FID) techniques, twenty-one chemical compounds were identified which represent a 96.33 % of the total essential oil. The main compounds were: γ-curcumene (55.61 %), Italicene (4.69 %), α-cubebene (4.45 %), δ-cadinene (4.28 %) and α-pinene (3.57 %). The antimicrobial activity and antifungal activity of this essential oil was assayed against two Gram positives bacterium: Enterococcus faecalis and Staphylococcus aureus; five Gram negatives bacterium: Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus vulgaris, Escherichia coli and Salmonella Tiphymurium; and three fungi: Tricophyton mentagrophytes, Tricophyton rubrum and Aspergillus niger. The essential oil was inactive against all bacterium at the maximum concentration tested 1000 μg/mL. However, the essential oil from G. elegans presented a moderate activity against Trichophyton rubrum and Trichophyton mentagrophytes with a MIC of 500 μg/mL and 1000 μg/mL, respectively. This is the first report on the chemical composition and biological activity of essential oil from this species. [ABSTRACT FROM AUTHOR]

The current concern about resistance to acaricides and the impact of toxic waste on the environment has led to the search of vegetal alternatives in the control of the brown tick of the dog Rhipicephalus sanguineus. Schinus molle L. (Anacardiaceae) derivatives have been associated with insecticidal, antimicrobial and antiprotozoal activities and essential oil showed to be lethal to R. microplus larvae. This study aimed at evaluating the acaricidal effect of essential oil of S. molle (EOSm) on engorged adult females and larval stages of R. sanguineus. One-hundred engorged females were obtained from the ears, interdigital spaces, neck, groin and base of the tail of two cross-bred dogs. The larvae package test was accomplished with 21-day-old larvae and five concentrations (v/v) of EOSm (0.125, 0.25, 0.50, 1 and 2%) in an anionic detergent, a synthetic acaricide (cypermethrin) and detergent and deionized water as controls. The immersion adult test was carried out with nine concentrations (0.125, 0.25, 0.50, 1, 2, 4, 8, 16, 20%) of the EOSm. At the concentration of 2%, EOSm caused 99.3% of larval mortality. In adults, inhibition of oviposition, egg hatching (EH) and reproductive efficiency (RE) values were dose-dependent from 4 to 20% EOSm; the lowest values of EH (29.62) and RE (22.61) were achieved with 20% EOSm. Strong and negative correlations were found between concentration of EOSm and EH (r = − 0.948) and between concentration of EOSm and RE (r = − 0.985). This study demonstrated for the first time the acaricidal effect of EOSm on larvae and reproductive parameters of engorged adult females of R. sanguineus. [ABSTRACT FROM AUTHOR]

Ethnobotanical and ethnomedicinal relevance The importance given in Ecuador to the rescue of traditional knowledge and nutritional value of ancestral foods and drinks, has stimulated our investigation of the chemical composition and some biological activities of M. fragrans (‘arrayán’) essential oil, a natural aromatic additive used in the preparation of the traditional fruit-juice ‘colada morada’, which is typically drunk in the Day of the Dead or All Soul´s Day. Material and methods Different essential oils of Myrcianthes fragrans (Sw.) McVaught were obtained by hydrodistillation of the aerial parts of the plant collected in Cerro Villonaco (Loja-Ecuador) at three different phenological growth stages, i.e., during foliation (Fo), flowering (Fl) and fruiting (Fr) stages. The chemical compositions of the essential oils were determined by GC/MS and GC/FID techniques. The antimicrobial activities were determined by the broth microdilution method and reported as minimal inhibitory concentration (MIC, ug/mL). Aims of the study i) to investigate the traditional uses of arrayán ( M. fragrans ) in the South region of Ecuador; ii) to identify the main components of the essential oils isolated at different phenological stages; iiì) to test the antimicrobial activity of the essential oils against bacteria and yeasts causing human ailments and a yeast causing food spoilage. Results 37, 46 and 38 compounds, representing 96.5%, 96.2%, and 95.6% of the three essential oils (Fo, Fl and Fr), respectively, have been identified. Oxygenated monoterpenes (OM) were the major components with percentages of 63.1 (Fo), 49.4 (Fl), and 61.9% (Fr), respectively. The main constituents of the essential oils were the monoterpene aldehydes geranial ( 1 ) and neral ( 2 ), the content of which varied, depending on the phenological development stage of the plant, spanning from 31.1% and 23.6% (Fo), to 23.6% and 17.8% (Fl), and 29.7% and 24.3% (Fr), respectively. In vitro antimicrobial tests showed that the essential oils from M. fragrans exhibited good activity against the Gram-negative bacteria, K. pneumoniae , and against the yeasts, C. albicans and S. cerevisiae . Conclusions The oil is characterized by a high concentration of the monoterpene aldehydes geranial and neral (citral), that make the aroma of colada morada prepared in southern Ecuador quite different from the beverage made in other regions of the country, where other types of myrtles (Myrtaceae spp.) are used. Moreover, the oil may become a new rich source of the important industrial chemical citral. The pleasant aromatic properties and the good in vitro antimicrobial activity of arrayán oil suggest a plausible scientific explanation for the traditional uses of the plant not only as a natural aromatizer of a traditional beverage but also as a natural anti-infective and anti-yeast agent. [ABSTRACT FROM AUTHOR]

Breutelia tomentosa (Sw. ex Brid.) A. Jaeger, Leptodontium viticulosoides (P. Beauv.) Wijk & Margad., Macromitrium perreflexum Steere, Campylopus richardii Brid., Rhacocarpus purpurascens (Brid.) Paris., and Thuidium peruvianum Mitt. essential oils were obtained by hydrodistillation. Using gas chromatography/flame ionization detector (GC/FID) and Gas chromatography/Mass spectrometry (GC/MS), a total of ninety four constituents were identified, representing for 80.5 93.8 % of the chemical composition. The major components were epizonarene (8.7 %) and α-selinene (6.7 %) in the oil of B. tomentosa, β-selinene (13.5 %) and α-selinene (10.5 %) in the oil of L. viticulosoides, selina-3,11-dien-6-α-ol (19.7 %) and curcuphenol (10.6 %) in the oil of M. perreflexum, epi-α-muurulol (15.1 %) and α-cadinol (12.5 %) in the oil of C. richardii. α-cadinol (36.8 %) and α-santalene (8.4 %) in the oil of R. purpurascens, and phytol (21.7 %) and valerenol (10.1 %) in the oil of T. peruvianum. [ABSTRACT FROM AUTHOR]

The use of bio-derivatives as acaricides would be an effective and safe method of tick control. The acaricidal effect of essential oils obtained fromBursera graveolens(Burseraceae) andSchinus molle(Anacardiaceae), traditionally used by indigenous Ecuadorian medicine as insecticides, was tested on larvae of cattle tickRhipicephalus(Boophilus)microplus.Essential oils were obtained from mature fruits by hydrodistillation and analyzed by gas chromatography. The acaricidal activity of essential oils against larvae was measured by larval package test with six concentrations of each essential oil. In total, sixteen compounds were identified inB. graveolensand twenty-one inS. molleessential oil.The mortalities of larvae in assays conducted withB. graveolensessential oil ranked from 35.43 to 100%; inS. mollefrom 5.58 to 100%. The obtained results show a clear and promising acaricidal effect of both essential oils over larvae ofR. (B.) microplus. [ABSTRACT FROM PUBLISHER]

The essential oil of aerial parts from Baccharis obtusifolia (Asteraceae) growing wild in Ecuador was obtained by hydrodistillation and examined by gas chromatography–mass spectrometry (GC–MS and GC–flame ionization detector (GC–FID) analysis. Thirty-one individual compounds were identified and constitute 96.1% of the total composition of the oil. The main constituents of the oil were limonene (28.3%), germacrene-D (9.8%), α-pinene (9.0%), β-pinene (8.2%), bicyclogermacrene (6.2%) and δ-cadinene (5.7%). The essential oil showed significant antibacterial and antifungal activity. Baccharis obtusifolia oil exhibited a moderate antibacterial effect against Klebsiella pneumoniae (ATCC 9997) and Enterococcus faecalis (ATCC 29212), and good antifungal activity against Trichophyton rubrum (ATCC 28188) and Trichophyton mentagrophytes (ATCC 28185). In this study, the chemical composition and biological activity of the essential oil of B. obtusifolia (Asteraceae) are reported for the first time. [ABSTRACT FROM AUTHOR]

Annona cherimola Mill. is a native species of Ecuador cultivated worldwide for the flavor and properties of its fruit. In this study, hydrodistillation was used to isolate essential oil (EO) of fresh Annona cherimola leaves collected in Ecuadorian Sierra. The EO chemical composition was determined using a non-polar and a polar chromatographic column and enantiomeric distribution with an enantioselective column. The qualitative analysis was carried out by gas chromatography coupled to a mass spectrometer and quantitative analysis using gas chromatography equipped with a flame ionization detector. The antibacterial potency was assessed against seven Gram-negative bacteria and one Gram-positive bacterium. ABTS and DPPH assays were used to evaluate the radical scavenging properties of the EO. Spectrophotometric method was used to measure acetylcholinesterase inhibitory activity. GC-MS analysis allowed us to identify more than 99% of the EO chemical composition. Out of the fifty-three compounds identified, the main were germacrene D (28.77 ± 3.80%), sabinene (3, 9.05 ± 1.69%), β-pinene (4, 7.93 ± 0.685), (E)-caryophyllene (10.52 ± 1.64%) and bicyclogermacrene (11.12 ± 1.39%). Enantioselective analysis showed the existence of four pairs of enantiomers, the (−)-β-Pinene (1S, 5S) was found pure (100%). Chirimoya essential oil exhibited a strong antioxidant activity and a very strong anticholinesterase potential with an IC50 value of 41.51 ± 1.02 µg/mL. Additionally, EO presented a moderate activity against Campylobacter jejuni and Klebsiella pneumoniae with a MIC value of 500 μg/mL. [ABSTRACT FROM AUTHOR]

Control measures against common cattle tick Rhipicephalus microplus are of the upmost importance because of considerable, deleterious impact on a farm's economy. Due to resistance phenomena to synthetic acaricides being a constraint in affected farms, the search for plant derivatives as acaricides has increased dramatically in recent years. In this work, essential oils obtained from two Ecuadorian plants, Ambrosia peruviana and Lepechinia mutica (EOAp, EOLm), traditionally used as insecticides in indigenous communities, were studied on larvae and engorged females at the parasitic stages of R. microplus. Larvae and females were treated with five (0.0625, 0.125, 0.25, 0.50 and 1%) and six concentrations (0.125, 0.25, 0.50, 1, 2 and 4%), respectively, of each EOsAp/Lm. A 98–99% larval mortality was achieved with 0.5% of both EOsAp/Lm. EOAp inhibited oviposition and egg hatching up to 82% and 80%, respectively, and had an overall efficacy of 93.12%. Efficacy of EOLm was 72.84%, due to the low influence of EOLm on reproductive parameters. By steam distillation and GC-MS analysis, γ-Curcumene was identified as the main constituent (52.02%) in the EOAp and Shyobunol (10.80%) in EOLm. The results suggest that major components of both essential oils should be further studied as promissory acaricides against R. microplus. [ABSTRACT FROM AUTHOR]

The essential oil of aerial parts ofBaccharis latifolia(asteraceae) growing wild in Ecuador was obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) and GC/flame ionization detector (GC/FID). Twenty-nine compounds, representing 90.91% of the oil, were identified. The major components were limonene (33.72%),-phellandrene (10.32%), sabinene (10.28%), β-pinene (6.99%) and α-pinene (5.44%). The antifungal and antibacterial activities were determined by the broth microdilution method. The essential oil fromB.latifoliaexhibited activity only againstTrichophyton rubrum(ATCC 28188) andTrichophyton mentagrophytes(ATCC 28185). [ABSTRACT FROM PUBLISHER]

Scutellaria volubilis and Lepechinia paniculata belong to the Lamiaceae family of species. They are used widely in traditional medicine in Ecuador. The physical properties and chemical composition of the essential oils from the aerial part of Scutellaria volubilis in its foliation -- flowering stage and Lepechinia paniculata in its flowering phase have been studied after their hydrodistillation. The components of these essential oils were investigated by means of gas chromatography/mass spectrometry (GC/MS) and gas chromatography/flame ionization detection (GC/FID) techniques. Thirty-seven components were determined in the essential oil of 5. volubilis. The principal constituents were found to be sesquiterpene hydrocarbons: germacrene D (20.4%), β-caryophyllene (17.5%), α-humulene (14.7%) and β-bisabolene (5.8%). Thirty-four components were identified in the essential oil of L. paniculata, the principal groups were sesquiterpene hydrocarbons such as aromadendrene (24.6%), viridiflorene (12.4%), β-selinene (7.4%) and valencene (6.7%). The monoterpene hydrocarbons were present in lower amounts as well as β-phellandrene (6.9%) and (7.7%). Oxygenated monoteipenes and sesquiterpenes contribute below 5% in both species. This is the first report on the chemical composition of this species. [ABSTRACT FROM AUTHOR]

Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography–gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the principal constituent in male (28.24 and 25.90%) and female (26.47 and 23.90%) essential oil. Other main compounds were methyl chavicol, germacrene D, methyl eugenol, and α-pinene. Female essential oil presented a strong activity against Klebsiella pneumoniae (ATCC 9997) with an minimum inhibitory concentration (MIC) of 500 μg/mL and a scavenging capacity SC50 of 800 µg/mL. [ABSTRACT FROM AUTHOR]

Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for wound healing and as an antiseptic. In this study, fresh Croton ferrugineus leaves were collected and subjected to hydrodistillation for extraction of the essential oil. The chemical composition of the essential oil was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against three Gram-positive bacteria, one Gram-negative bacterium and one dermatophyte fungus. The radical scavenging properties of the essential oil was evaluated by means of DPPH and ABTS assays. The chemical analysis allowed us to identify thirty-five compounds representing more than 99.95% of the total composition. Aliphatic sesquiterpene hydrocarbon trans-caryophyllene was the main constituent with 20.47 ± 1.25%. Other main compounds were myrcene (11.47 ± 1.56%), β-phellandrene (10.55 ± 0.02%), germacrene D (7.60 ± 0.60%), and α-humulene (5.49 ± 0.38%). The essential oil from Croton ferrugineus presented moderate activity against Candida albicans (ATCC 10231) with an MIC of 1000 μg/mL, a scavenging capacity SC50 of 901 ± 20 µg/mL with the ABTS method, and very strong antiglucosidase activity with an IC50 of 146 ± 20 µg/mL. [ABSTRACT FROM AUTHOR]

Ocotea quixos (Lam.) Kosterm. is an aromatic tree native to Ecuador, whose leaves are used to prepare aromatic beverages to which different health benefits are attributed. In this study, Ocotea quixos leaves were collected in the Amazon region in different environmental conditions and subjected to hydrodistillation to isolate the essential oil. The collection variables used were type of soil, amount of shade, and height; in addition, the presence of twig and leaf age and moisture were used as variables. Chemical composition was analyzed by means of gas chromatography equipped with a flame ionization detector and gas chromatography coupled to mass spectrometry. A wide variety of chemical compositions were detected in the samples. In total, forty-seven compounds were identified, which represented between 97.17% and 99.89% of the total composition. The constituents were mainly grouped into aliphatic sesquiterpene hydrocarbons (33.03–55.89%), other compounds (8.94–47.83%), and oxygenated monoterpenes (1.97–39.66%). The main constituents were found to be (E)-cinnamyl acetate (5.96–41.65%), (E)-methyl cinnamate (0.38–37.91%), and trans-caryophyllene (8.77–37.02%). The statistical analysis suggested the existence of two essential oil chemotypes and a direct correlation between environmental conditions and chemical composition of the essential oils. [ABSTRACT FROM AUTHOR]

Piper carpunya Ruiz & Pav. is an aromatic shrub native to Ecuador, the leaves of which are used to prepare the traditional beverage Guaviduca. Different health benefits are attributed to the guaviduca beverage, which is consumed as a traditional and folk medicine. In this study, fresh P. carpunya leaves were collected in the winter and summer and subjected to hydrodistillation for the extraction of the essential oil. The guaviduca beverage was prepared by infusion in water and the volatile compounds were isolated by liquid–liquid extraction. Chemical composition and enantioselective analyses were performed by gas chromatography. The antibacterial activity was assayed against Gram-positive and Gram-negative bacteria. The scavenging radical properties of the essential oil was evaluated by 2,2-diphenyl-1-picrylhydryl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. The acetylcholinesterase inhibitory activity was measured using the spectrophotometric method. The chemical analysis allowed us to identify more than 98% of the compounds in all samples. The main constituent of the essential oil was 1,8-cineole (25.20 ± 1.31%) in P. carpunya collected in winter and (17.45 ± 2.33%) in P. carpunya collected in summer, while in the beverage, there was 14 mg/L. Safrole was identified in the essential oil (PCW 21.91 ± 2.79%; PCS 13.18 ± 1.72%) as well as in the beverage (2.43 ± 0.12 mg/L). Enantioselective analysis was used to investigate the enantiomeric ratio and excess of four chiral components. The essential oil presented a strong activity against Klebsiella pneumoniae with a MIC of 500 μg/mL and a very strong anticholinesterase activity with an IC50 of 36.42 ± 1.15 µg/mL. [ABSTRACT FROM AUTHOR]

Essential oils are highly demanded substances worldwide. They can be used without modification due to their different chemical and biological properties or as natural sources of chemical compounds. The limit in the use of these metabolites is their low yield. In the present investigation, the essential oil of fruits from Dacryodes peruviana collected in the Ecuadorian Amazon was extracted and studied. The essential oil was released from the plant matrix and isolated by hydrodistillation. The yields obtained were 4.8 ± 0.2% and 11.3 ± 0.2% for fresh and dried fruits, respectively, one of the highest yields on record to date. Twenty-five chemical compounds were identified by GC/MS and GC/FID techniques. The principal constituent was α-phellandrene, with 50.32 ± 3.32%. The antimicrobial activity of the oil was assayed against five Gram negative bacteria, two Gram positive bacteria and two fungi. The essential oil exerted a moderate activity against Staphylococcus aureus. The repellent activity of the oil was assayed against mosquitoes (Diptera: Culicidae); the samples with 3%, 2% and 1% essential oil were class 4, and the sample with 0.5% showed to be class 3. The essential oil showed a weak antioxidant activity through the DPPH and ABTS methods. [ABSTRACT FROM AUTHOR]

Volatile metabolites from Frullania brasiliensis Raddi, Herbertus juniperoideus (Sw.) Grolle, Leptoscyphus hexagonus (Nees) Grolle, and Syzygiella anomala (Lindenb. & Gottsche) Steph collected in the south of Ecuador were investigated. Volatile secondary metabolites were extracted by hydrodistillation and analyzed by gas chromatography/flame ionization detector (GC/FID) and Gas chromatography/Mass spectrometry (GC/MS). Sixty-seven volatile compounds were identified in the four species, which represent between 80.12–90.17% of the total chemical composition. The major components were τ-muurolol (32.14%) and Germacrene-D (11.98%) in the essential oil of F. brasiliensis, bicyclogermacrene (18.23%), and Caryophyllene oxide (15.29%) in the oil of H. juniperoideus, Cabreuva oxide D (33.77%) and Elemol (18.55%) in the oil of Leptoscyphus hexagonus, and Silphiperfola-5,7(14)-diene (25.22%) and Caryophyllene oxide (8.98%) in the oil of Syzygiella anomala. This is the first report on volatile compounds for the species Herbertus juniperoideus, Leptoscyphus hexagonus, and Syzygiella anomala. [ABSTRACT FROM AUTHOR]

The efficiency of wastewater treatment systems is measured in terms of physicochemical and biological parameters. In this study two-stages of treatment were evaluated for the phosphate and microbial removal from wastewater for agricultural purposes. Iron (oxy)hydroxide was incorporated into a natural clay for phosphate removal and essential oils (Eucalyptus globulus and Citrus limon) were used for microbial reduction from wastewater. An overall experimental evaluation was performed from synthetic wastewater and further validated in real wastewater in batch mode. Phosphate adsorption capacity of iron (oxy)hydroxide clay (PMFe 5) was three times higher than parent clay (PMFe 1). Phosphate removal by PMFe 5 was effective at neutral pH, which is attributed to physical and chemical adsorption mechanisms by means of hydrogen bonding adsorption and chemical complexation reactions, respectively. PMFe 5 removed phosphate and ammonium at 65.8% and 72.3%, respectively from real wastewater. On the other hand, the use of emulsions of Eucalyptus globulus and Citrus limon essential oils allowed the decrease of bacterial load from wastewater. The microbial reduction was more effective using Eucalyptus globulus than Citrus limon essential oil. The fecal and total coliforms were reduced to a maximum extent of 100% using Eucalyptus globulus at 100 mg L−1. Microbial content was reduced to 100% using Citrus limon at 1000 mg L−1. Thus, reusability of wastewater for irrigation purposes is possible using an iron clay and essential oils. The use of PMFe 5 as tertiary treatment stage could be crucial to recover phosphate–phosphorous from wastewater treatment plants reaching the regulatory levels. The content of total and fecal coliforms was also efficiently reduced using essential oils. On one hand, wastewater can be reused in irrigation activities according to the water quality standards. On the other hand, a nutrient enriched material can be provided as phosphate source for soil amendment application. The combination of both treatment technologies provides important agricultural supplies. [Display omitted] • An iron (oxy)hydroxide clay removed phosphate and ammonium from wastewater. • Essential oils were used for the reduction of total and fecal coliforms from wastewater. • Eucalyptus globulus essential oil at 100 mg L−1 reduced 100% of bacterial load. • Citrus limon essential oil 1000 mg L−1 reduced 100% of bacterial load. • Agricultural supplies obtained: nutrient-enriched clay and wastewater for irrigation. [ABSTRACT FROM AUTHOR]

The essential oil (EO) was obtained by hydrodistillation from the aerial parts of Lepechinia radula Benth Epling (Lamiaceae) from Ecuador. Thirty-four compounds accounting to 93.4% of the total oil were identified. The main constituents of the essential oil were δ-3-carene (19.9%), β-pinene (17.0%), (E)-β- caryophyllene (9.7%) and (E-E)-α-farnesene (9.4%). The essential oil of L. radula possessed strong antifungal activity against Trichophyton rubrum (ATCC® 28188) and Trichophyton mentagrophytes (ATCC® 28185). [ABSTRACT FROM AUTHOR]

Plant essential oils are promising tools for the management of insect infestations in stored beans. However, how these biorational products exert their insecticidal actions remains unknow. Here, we evaluated the insecticidal and repellent potential of Bursera graveolens essential oil against the bean weevil species Acanthoscelides obtectus and Zabrotes subfasciatus. By using chemical and in silico analyses, we evaluated the molecular interactions of the essential oil constituents with two potential physiological targets in stored beans: acetylcholinesterase (AChE) enzymes and transient receptor potential (TRP) channels. Our results revealed limonene (44%), phellandrene (24%), cymene (13%), and menthofuran (11%) as the major constituents of the essential oil. Both bean weevil species were similarly killed by the fumigant essential oil. However, while Z. subfasciatus individuals were repelled only at high essential oil concentrations (LC 95 = 156 μL/L), the essential oil LC 15 (44 μL/L) was enough to repel A. obtectus individuals. Our computational predictions revealed that all essential oil constituents formed stable molecular interactions (binding affinity < −5.5 kcal/mol) with the binding sites of acetylcholinesterase and TRP channels, suggesting the involvement of these targets in the essential oil actions. Altogether, our findings show that B. graveolens essential oil may exert its insecticidal actions by disrupting the functions of AChE and TRP channels and that it may be used as an alternative tool for the control of bean weevils [Display omitted] • Bursera graveolens essential oil prevents infestations of insects in stored beans. • The B. graveolens oil is rich in monoterpenes (limonene, phellandrene and cymene). • Acetylcholinesterases enzymes are targeted by B. graveolens essential oil. • Transient receptor potential channels are targeted by B. graveolens essential oil. • The B. graveolens oil showed potential as alternative control tools of bean weevils. [ABSTRACT FROM AUTHOR]