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In the present research, the essential oil from Piper lineatum Ruiz & Pav. was analysed by GC/MS and GC/FID, respectively. A total of thirty-seven chemical compounds were identified, which represented 98.9% of the essential oil composition. The main compounds were apiole (21.5%), safrole (19.2%), and myristicin (13.8%), respectively. The in vitro antimicrobial activity and antifungal activity of the oil was assayed against two Gram positive bacteria, five Gram negative bacteria and two fungi. The essential oil from P. lineatum showed an inhibitory activity against Gram-positive bacterium Klebsiella pneumoniae (ATCC 9997), and against dermatophytic fungus Trichophyton rubrum (ATCC 28188) with a MIC of 500 μg/mL in both cases. The antioxidant activity of essential oil was explored using DPPH and ABTS radical scavenging method, by means of both assays the essential oil showed a weak antioxidant activity. To the best of our knowledge, this is the first report on the chemical composition and biological activity of essential oil from this species.

Hedyosmum racemosum (Ruiz &amp, 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.

Phytochemical investigation of Croton thurifer, collected in Loja-Ecuador, led to the isolation of seven known compounds identified as: (3R, 20S) -3-palmitate-20-hydroxydammar-24-ene (1); (3R, 20S)-3-acetoxy-20-hydroxydammar-24-ene (2); trans-phytol (3); vomifoliol (4); β-sitosterol (5); trans-tiliroside (6) and sparsifol (7). The structures of the isolated compounds were determined by NMR, MS, as well as by comparison with literature data. The hypoglycemic activity of the crude extracts and isolated compounds was assessed by their ability to inhibit α-glucosidase activity. The hexane and methanol extracts did not show any inhibitory activity on α-glucosidase, while the ethyl acetate extract (EtOAc) showed very low inhibitory activity with IC50= 1.77 mg/mL. Two of the seven isolated compounds exhibited good inhibitory activity with IC50 values much higher than acarbose (377 μg/mL). trans-tiliroside was the compound with the highest inhibitory activity (IC50 = 114.85 μg / mL), while (3R, 20S)-3-Acetoxy-20-hydroxydammar-24-ene had moderate inhibitory activity (IC50=292.87). Trans-tiliroside exherted a non-competitive inhibition with Km values between 368 and 358 μM and Vmax value from 695 and 325 nM/min for unhibited and inhibited reaction, respectively and a Ki of 163,6 μM.

Recently, the search for novel therapeutic agents against Acanthamoeba species has been focused on the evaluation of natural resources. Among them, marine microorganisms have risen as a source of bioactive compounds with the advantage of the ability to obtain unlimited and constant amounts of the compounds in contrast to other natural sources such as plants. Furthermore, marine actinomycetes have recently been reported as highly rich in bioactive agents including salinosporamides, xiamycines, indolocarbazoles, naphtyridines, phenols, dilactones such as antimycines and macrolides among others. In this study, staurosporine (STS) was isolated from a strain of Streptomyces sanyensis and tested against Acanthamoeba to characterize the therapeutic potential of STS against this protozoan parasite. We have established that STS is active against both stages of the Acanthamoeba life cycle, by the activation of Programmed Cell Death via the mitochondrial pathway of the trophozoite. We have also established that STS has relatively low toxicity towards a macrophage cell line. However, previous studies have highlighted higher toxicity levels induced on other vertebrate cell lines and future research to lower these toxicity issues should be developed.

The phytochemistry of Cynophalla mollis (Kunth) J. Presl and Colicodendron scabridum (Kunth), both belonging to the family Capparaceae, were investigated in this study for the first time. Lupeol, betulin, lutein, stachydrine and quercetin-3,4'-di-O-rhamnoside were isolated from C. mollis, whereas C. scabridum afforded lupeol, lutein, stachydrine, β-sitosterol, stigmasterol, betonicine and narcissoside. All these compounds were purified by preparative liquid chromatography, in both open column and instrumental (MPLC) separation systems. Preparative TLC was also applied. They were all identified by 1 H- and 13 C-NMR experiments. The complete structure of the very rare flavonoid quercetin-3,4'-di-O-rhamnoside was fully elucidated through DEPT-135, COSY, HMQC and HMBC experiments, together with UV/VIS and FT-IR spectrophotometry. Complete NMR data for quercetin-3,4'-di-O-rhamnoside in deuterated methanol were presented here for the first time. All the extracts did not exert antioxidant activity at the maximum tested dose of 1 mg/mL. Three out of the nine isolated compounds exerted a good spectrum of antioxidant capacity, being narcissoside the most active against ABTS radicals, with SC50 =12.43 μM. It was followed by lutein and quercetin-3,4'-di-O-rhamnoside, with 40.92 μM and 46.10 μM, respectively.

Piper carpunya Ruiz &amp, 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.

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 &plusmn, 0.2% and 11.3 &plusmn, 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 &alpha, phellandrene, with 50.32 &plusmn, 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.

Chagas disease and leishmaniasis are neglected tropical diseases caused by kinetoplastid parasites of Trypanosoma and Leishmania genera that affect poor and remote populations in developing countries. These parasites share similar complex life cycles and modes of infection. It has been demonstrated that the particular group of phosphorylating enzymes, protein kinases (PKs), are essential for the infective mechanisms and for parasite survival. The natural indolocarbazole staurosporine (STS, 1) has been extensively used as a PKC inhibitor and its antiparasitic effects described. In this research, we analyze the antikinetoplastid activities of three indolocarbazole (ICZs) alkaloids of the family of staurosporine STS, 2&ndash, 4, and the commercial ICZs rebeccamycin (5), K252a (6), K252b (7), K252c (8), and arcyriaflavin A (9) in order to establish a plausive approach to the mode of action and to provide a preliminary qualitative structure&ndash, activity analysis. The most active compound was 7-oxostaurosporine (7OSTS, 2) that showed IC50 values of 3.58 &plusmn, 1.10, 0.56 &plusmn, 0.06 and 1.58 &plusmn, 0.52 &micro, M against L. amazonensis, L. donovani and T. cruzi, and a Selectivity Index (CC50/IC50) of 52 against amastigotes of L. amazonensis compared to the J774A.1 cell line of mouse macrophages.

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 (‘arrayan’) 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 arrayan (M. fragrans) in the South region of Ecuador; ii) to identify the main components of the essential oils isolated at different phenological stages; iii) 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 arrayan 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.

Shrimp (Litopenaeus vannamei) farming is an important economic activity in several countries. Pathogens in shrimp farms and its effluents pose a potential hazard for both humans and shrimps. Wild strains of bacteria were characterized in a shrimp farm, and Klebsiella pneumoniae was chosen as a good indicator due to its presence in the pond and the effluent and its resistance to antibiotics. Different photochemical processes (UV/H2O2, UV/H2O2/Fe3+) were tested for inactivation of wild isolated K. pneumoniae and compared to UV-C radiation. By kinetic modelling, a kmax equal to 0.43 s−1 was obtained for UV-C treatment. After optimizing the cited processes, ranging [H2O2]: 10–30 mg·l−1; an optimal [H2O2] of 10 mg·l−1 was found, increasing kmax on 13.63% compared to UV-C. This optimal concentration was tested for UV/H2O2/Fe3+ process; ranging [Fe3+]: 2–20 mg·l−1. The highest yield was obtained by a [H2O2]:[Fe3+] = 10:2, which leads to 4-Log reduction in 12.88 s of treatment. Moreover, resistance of K. pneumoniae was compared to Escherichia coli. The latter proved to be more sensitive despite its similar cellular structure. Results suggested that the photochemical processes could enhance disinfection efficiency, especially for photo-assisted Fenton-like process in most resistant bacteria.

Indolocarbazoles are a family of natural alkaloids characterized by their potent protein kinase and topoisomerase I inhibitory activity. Among them, staurosporine (1) has exhibited promising inhibitory activity against parasites. Based on new insights on the activity and mechanism of action of STS in Acanthamoeba parasites, this work reports the isolation, identification, and the anti-Acanthamoeba activity of the minor metabolites 7-oxostaurosporine (2), 4&prime, demethylamino-4&prime, oxostaurosporine (3), and streptocarbazole B (4), isolated from cultures of the mangrove strain Streptomyces sanyensis. A clear correlation between the antiparasitic activities and the structural elements and conformations of the indolocarbazoles 1&ndash, 4 was observed. Also, the study reveals that 7-oxostaurosporine (2) affects membrane permeability and causes mitochondrial damages on trophozoites of A. castellanii Neff.

The species Croton elegans Kunth, belonging to the family Euphorbiaceae and known with the common name “mosquera”, is a native medicinal plant of Ecuador. Due to its medical applications, we are interested in secondary metabolite composition. After extraction with hexane and preparation of the alkaloid extract, preparative chromatographic fractionation in both normal and direct phase was performed. 1 H NMR, 13 C NMR, HSQC and HMBC experiments, together with polarimetric measurements, were conducted in order to characterize the purified compunds. Two triterpene metabolites (friedelin and cycloeucalenol) and two morphinan alkaloids ( (+) -pallidine and (+) - O -methylpallidine) were obtained in a pure form. This work represents the first report on the phytochemistry of C. elegans and probably the second publication on the natural (+) -pallidine alkaloid.

The phytochemical investigation of both volatile and fixed metabolites of Clinopodium taxifolium (Kunth) Govaerts (Lamiaceae) was performed for the first time. It allowed the isolation and characterization of the essential oil and six known compounds: carvacrol (1), squalane (2), uvaol (3), erythrodiol (4), ursolic acid (5), and salvigenin (6). Their structures were identified and characterized by Nuclear Magnetic Resonance (NMR) and Gas Chromatography coupled to Mass Spectroscopy (GC-MS), and corroborated by literature. The essential oil of the leaves was obtained by hydrodistillation in two different periods and analyzed by GC-MS and GC coupled to Flame Ionization Detector (GC-FID). A total of 54 compounds were detected, of which 42 were identified (including trace constituents). The major constituents were carvacrol methyl ether (18.9–23.2%), carvacrol (13.8–16.3%) and, carvacryl acetate (11.4–4.8%). The antibacterial activities were determined as Minimum Inhibition Concentration (MIC) against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa and Micrococcus luteus. The hexane and methanol extracts exhibited activity only against Klebsiella pneumoniae (250 and 500 μg/mL respectively), while the ethyl acetate extract was inactive. The hypoglycemic activity was evaluated by the in vitro inhibition of α-glucosidase. The ethyl acetate (EtOAc) extract showed strong inhibitory activity with IC50 = 24.88 µg/mL, however methanolic and hexanic extracts showed weak activity. As a pure compound, only ursolic acid showed a strong inhibitory activity, with IC50 = 72.71 μM.

International audience; This study investigated the chemical composition, physical proprieties, biological activity, and enantiomeric analysis of the essential oil from the aerial parts of Niphogeton dissecta (culantrillo del cerro) from Ecuador, obtained by steam distillation. The qualitative and quantitative analysis of the essential oil was realized by gas chromatographic and spectroscopic techniques (GC-MS and GC-FID). Acorenone B was identified by GC-MS and NMR experiments. The enantiomeric distribution of some constituents has been assessed by enantio-GC through the use of a chiral cyclodextrin-based capillary column. We identified 41 components that accounted for 96.46% of the total analyzed, the major components were acorenone B (41.01%) and (E)-β-ocimene (29.64%). The enantiomeric ratio of (+)/(-)-β-pinene was 86.9:13.1, while the one of (+)/(-)-sabinene was 80.9:19.1. The essential oil showed a weak inhibitory activity, expressed as Minimal Inhibitory Concentration (MIC), against Enterococcus faecalis (MIC 10 mg/mL) and Staphylococcus aureus (MIC 5 mg/mL). Furthermore, it inhibited butyrylcholinesterase with an IC50 value of 11.5 μg/mL. Pure acorenone B showed inhibitory activity against both acetylcholinesterase and butyrylcholinesterase, with IC50 values of 40.8 μg/mL and 10.9 μg/mL, respectively.

Amoxicillin (AMOX) was successfully encapsulated at different concentrations into poly(epsilon-caprolactone) (PCL) by the electrospinning technique, and mats of non-woven fibers were obtained and characterized in terms of morphology, in vitro release and antibacterial properties. The scanning electron microscopy evidenced the nanofibrous structure of the pristine PCL, composed of individual, uniform, and randomly oriented fibres with an average diameter ranging around 0.8 micron. The addition of amoxicillin at different concentrations (3, 5 and 7 wt%) did not evidence change in the fiber morphology. The release curves, for all samples, present mainly two stages: a first stage, quick as a "burst," is followed by a second slow stage. The burst was analyzed as a function of amoxicillin concentration and thickness of the membranes, and values corresponding to absence of burst were individuated. In the second stage the release was found very slow extending up to months for the most concentrated sample. The antibacterial activity of the electrospun fibers was effective to inhibit in different proportions Staphylococcus aureus, Enterococcus faecalis and Escherichia coli. The properties of the filled membranes and their capability for local delivery of antibiotics make them suitable for biomedical applications.

The MeOH extract of Piper ecuadorense Sodiro, Piperaceae, was chosen for metabolite isolation and elucidation due to the strong antifungal activity exhibited, measured by means of the broth microdilution method. Two known flavonoids: pinostrobin (1) and pinocembrin (2) were isolated from 4.16 g. of dichloromethane extract by column chromatography, using a gradient of hexane/EtOAc. A total of 20 mg of 1 were obtained from the fraction eluted with hexane-EtOAc 95:5 v/v, and 100 mg of 2 were obtained from the fraction eluted with hexane-EtOAc 85:15 v/v. The MIC values of the MeOH extract was 31.25 μg/mL for Trichophyton mentagrophytes ATCC® 28185 and 62.5 μg/mL for Trichophyton rubrum ATCC® 28188. The MIC value of pinocembrin was 125 μg/mL for Trichophyton mentagrophytes ATCC® 28185 and Trichophyton rubrum ATCC® 28188. Pinostrobin in antifungal test was not active against fungi tested. Keywords: antifungal activity, flavonoids, pinocembrin, pinostrobin, Piper ecuadorense, matico de monte

The phytochemical investigation of Muehlenbeckia tamnifolia, collected in Loja-Ecuador, led to the isolation of nine known compounds identified as: lupeol acetate (1); cis-p-coumaric acid (2); lupeol (3); β-sitosterol (4) trans-p-coumaric acid (5); linoleic acid (6) (+)-catechin (7); afzelin (8) and quercitrin (9). The structures of the isolated compounds were determined based on analysis of NMR and MS data, as well as comparison with the literature. The hypoglycemic activity of crude extracts and isolated compounds was assessed by the ability to inhibit α-amylase and α-glucosidase enzymes. The hexane extract showed weak inhibitory activity on α-amylase, with an IC50 value of 625 µg·mL−1, while the other extracts and isolated compounds were inactive at the maximum dose tested. The results on α-glucosidase showed more favorable effects; the hexanic and methanolic extracts exhibited a strong inhibitory activity with IC50 values of 48.22 µg·mL−1 and 19.22 µg·mL−1, respectively. Four of the nine isolated compounds exhibited strong inhibitory activity with IC50 values below 8 µM, much higher than acarbose (377 uM). Linoleic acid was the most potent compound (IC50 = 0.42 µM) followed by afzelin, (+)-catechin and quercitrin.

Context: Marine natural products are a rich source of potent, selective, and structurally novel compounds. Marine bacteria are considered the most promising source of biologically active compounds which can be applied to treat a wide range of diseases. Objective: The current study was designed to establish the bases for a future marine exploration in the Ecuadorian coast based on the molecular identification of a marine bacterium and its potential use as an antibacterial or cytotoxic compounds source. Materials and methods: Isolation and characterization of the marine bacterium were carried out through microbiological methods from desiccated sediment. Molecular identification was made by means of 16S rDNA analysis. MIC was measured by the microdilution broth method against six pathogenic bacteria: two Gram positive and four Gram negative strains. Cytotoxicity was evaluated by Crystal violet assay against breast adenocarcinoma (MCF7) and ductal carcinoma (T47D and ZR-75-30). Results: Our present study has shown that EtOAc extract and fraction A1 obtained from marine Streptomyces sp. revealed the maximal antibacterial and cytotoxic activity. Enterococcus faecalis was found to be more sensitive strain (MIC 0.78 ?g/ml) than the other five bacteria tested. ZR-75-30 and T47D cell lines were found to be more sensitive (IC50 value, 31.88 � 0.05 and 68.35 � 0.12 ?g/ml) than adenocarcinoma MCF7 (IC50 value was 83.65 � 0.06 ?g/ml). Discussion and conclusion: The results obtained herein indicate that EtOAc extract of Streptomyces sp. has shown a strong antibacterial activity as well as moderate cytotoxic activity which make it a good candidate for metabolite isolation. © 2015 Informa Healthcare USA, Inc.

The chemical composition, antifungal and antibacterial activity of essential oils isolated by hydrodistillation from the aerial parts of Chromolaena laevigata (asteraceae) growing wild in Ecuador, were evaluated. The chemical composition was analyzed analyzed by gas chromatography/mass spectrometry (GC/MS) and GC/flame ionization detector (GC/FID). Twenty-five volatile components were identify in essential oils, corresponding to 96,13% of the total oils. Essential oils was rich in laevigatin (46,84), germacrene D (15,38), viridiflorol (11,37), bicyclogermacrene (4,14), limonene (4,94) and ?-pinene (2,85). The antibacterial and antifungal activities were studied by the broth microdilution method. The antibacterial activity was tested against Gram-negative bacterial strains [Pseudomonas aeruginosa (ATCC 27853), Klebsiella pneumoniae (ATCC 9997), Proteus vulgaris (ATCC 8427), Escherichia coli (ATCC 25922) and Salmonella typhimurium (LT2)] and Gram-positive bacterial strains [Enterococcus faecalis (ATCC 29212) and Staphylococcus aureus (ATCC 25923)] and antifungal activity was determined against Trichophyton rubrum (ATCC 28188) and Trichophyton mentagrophytes (ATCC 28185). The essential oil from C. laevigata exhibited activity against Trichophyton rubrum (ATCC 28188) and Trichophyton mentagrophytes (ATCC 28185).

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.

The essential oil of aerial parts of Baccharis 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 from B. latifolia exhibited activity only against Trichophyton rubrum (ATCC 28188) and Trichophyton mentagrophytes (ATCC 28185).

Two phenols, bakuchiol (1) and 3-hydroxybakuchiol (2), and two isoflavone glycosides, daidzin (3) and genistin (4) were isolated from Otholobium mexicanum J. W. Grimes (Fabaceae). Moreover, the ability of the raw extract and isolated metabolites to inhibit the enzymes α-amylase and α-glucosidase was evaluated in vitro. In the α-amylase assay, the methanolic extract exhibited a moderate inhibitory activity with an IC50 of 470 μg/mL, while inhibition percentages of bakuchiol (1), 3-hydroxybakuchiol (2), and daidzin (3) were less than 25% at the maximum dose tested (1 μM). Genistin (4) exhibited a poor activity with an IC50 of 805 μM. In the α-glucosidase assay, the methanolic extract exhibited a strong inhibitory activity with an IC50 value of 32 μg/mL, while 3-hydroxybakuchiol (2) exhibited a moderate inhibitory activity with an IC50 of 345 μM. Daidzin (3) and genistin (4) exhibited lower inhibitory activity with IC50 values of 564 μM and 913 μM, respectively. Bakuchiol (1) exhibited a poor inhibitory activity with an inhibition percentage less than 10% at the maximum dose tested (1 mM).