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Staphylococcus aureus infections are prevalent in healthcare and community environments. Methicillin-resistant S. aureus is catalogued as a superbug of high priority among the pathogens. This Gram-positive coccus can form biofilms and produce toxins, leading to persistent infection and antibiotic resistance. Limited effective antibiotics have encouraged the development of innovative strategies, with a particular emphasis on resistance mechanisms and/or virulence factors. Medicinal aromatic plants have emerged as promising alternative sources. This study investigated the antimicrobial, antibiofilm, and antihemolysis properties of three different chemotypes of Lippia origanoides essential oil (EO) against susceptible and drug-resistant S. aureus strains. The chemical composition of the EO was analyzed using GC-MS, revealing high monoterpene concentrations, with carvacrol and thymol as the major components in two of the chemotypes. The third chemotype consisted mainly of the sesquiterpene ß-caryophyllene. The MIC values for the two monoterpene chemotypes ranged from 62.5 to 500 µg/mL for all strains, whereas the sesquiterpene chemotype showed activity against seven strains at concentrations of 125-500 µg/mL, which is the first report of its anti-S. aureus activity. The phenolic chemotypes inhibited biofilm formation in seven S. aureus strains, whereas the sesquiterpene chemotype only inhibited biofilm formation in four strains. In addition, phenolic chemotypes displayed antihemolysis activity, with IC50 values ranging from 58.9 ± 3.8 to 128.3 ± 9.2 µg/mL. Our study highlights the importance of L. origanoides EO from the Yucatan Peninsula, which has the potential for the development of anti-S. aureus agents.

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Satureja macrostema is a plant that is located in various regions of Mexico and is used in a traditional way against illness. Essential oils (EOs) were obtained from leaves Satureja macrostema and the chemical composition was evaluated by gas chromatography-mass spectrometry (GC-MS). The antioxidant effect of the oil was assayed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and by Trolox Equivalent Antioxidant Capacity (TEAC). In vitro antibacterial activity against Escherichia coli and Staphylococcus aureus was determined using a broth microdilution assay and thin layer chromatography-direct bioautography (TLC-DB) to identify active antibacterial compounds. The EOs analysis showed 21 compounds, 99% terpenes, and 96% oxygenated monoterpenes, with trans-piperitone epoxide (46%), cis-piperitone epoxide (22%), and piperitenone oxide (11%) as more abundant compounds. Likewise, S. macrostema EOs showed an antioxidant activity of DPPH = 82%, with 50% free radical scavenging (IC50) = 7 mg/mL and TEAC = 0.005, an antibacterial effect against E. coli of 73% inhibition, and 81% over S. aureus at dose of 100 µL of undiluted crude oil. The TLC-DB assay showed that the most active compounds were derived from piperitone. The comparison with other studies on S. macrostema shows variability in the compounds and their abundances, which can be attributed to climatic factors and the maturity of plants with similar antioxidant and antibacterial activities.

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Cannabis sativa L. has been used as medicine for thousands of years. Since the early identification of tetrahydrocannabinol (THC) in 1960, pharmacological activities were attributed to a group of unique structures named cannabinoids. For decades, research and development were applied to determine different cannabinoids and their medicinal properties. Nowadays there is evidence that the therapeutic benefits of the plant are based on the synergy of cannabinoids and other secondary metabolites such as terpenes and flavonoids. Differences between the medical performance of isolated compounds like cannabidiol (CBD) or THC and full-spectrum plant extracts are notable. Indeed, the superiority of the last one is provoked by the synergy between various different compounds. This improved medicinal effect is called the entourage effect. Chromatography has become the method of choice for the determination of cannabinoids, terpenes, and flavonoids, so it represents an excellent tool for a proper characterization of the plant and plant derived products. The objective of characterization relies not only in analyzing the fingerprint of cannabis, but also to identify different chemotypes for medical purposes. To understand the contributions of each natural product to this "entourage effect", this review presents an in-depth analysis of the utilization of High-performance liquid chromatography (HPLC), Gas chromatography (GC) and other methods for the analysis of phytocomponents of Cannabis sativa L. In this sense, a representative number of examples and advances made in the field together with limitations and future needs are provided. It can be concluded that standardized protocols and quality control policies and procedures are necessary for the comprehensive analysis of cannabis extracts and derivatives.

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This study reports the biotechnological importance of seven Lippia albaspecimens collected in different places in Brazil, and evaluation of some activities as larvicidal against Aedes spp., antifungal against dermatophytes; cytotoxicity against SNB-19 (astrocytoma), HCT-116 (human colon) and PC-3 (human prostate) cancer cell lines, and inhibition of the enzyme acetylcholinesterase (AChE). The essential oils, whose extraction yield was about 1.24 w/w ± 0.9%, showed differences in their chemical composition and considered as chemotypes. The essential oils containing neral and geranial as main constituents showed better action against HCT-116 cell lines (IC50 value was 9.22 µg/mL), larvicidal activity against arbovirus vectors (LC50 value against A. aegypti was 1.59 µg/mL) and inhibition of AChE (halo inhibition zone was 1 cm). The essential oils containing mainly monoterpenoids showed better antifungal action with MIC values range from 0.15 to 1.25 mg/mL. This chemical and biological characterization may be useful for biotechnological applications.

Este estudio reporta la importancia biotecnológica de siete especímenes de Lippia alba recolectados en diferentes lugares de Brasil, y evaluación de algunas actividades como larvicida contra Aedes spp., Antifúngico contra dermatofitos; citotoxicidad contra líneas celulares de cáncer SNB-19 (astrocitoma), HCT-116 (colon humano) y PC-3 (próstata humana), e inhibición de la enzima acetilcolinesterasa (AChE). Los aceites esenciales, cuyo rendimiento de extracción fue de aproximadamente 1,24 p/p ± 0,9%, mostraron diferencias en su composición química y se consideraron quimiotipos. Los aceites esenciales que contienen neral y geranial como constituyentes principales mostraron una mejor acción contra las líneas celulares HCT-116 (el valor de CI50 fue de 9.22 µg/mL), actividad larvicida contra los vectores de arbovirus (el valor de LC50 contra A. aegypti fue de 1.59 µg/mL) e inhibición de AChE (la zona de inhibición del halo era de 1 cm). Los aceites esenciales que contienen principalmente monoterpenoides mostraron una mejor acción antifúngica con valores de CMI en el rango de 0.15 a 1.25 mg/mL. Esta caracterización química y biológica puede ser útil para aplicaciones biotecnológicas.

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Annona emarginata (Annonaceae) has two morphological variations (A. emarginata 'mirim' and A. emarginata 'terra-fria'). The species has agricultural value and produces specialized metabolites of pharmacological interest. The objective of this work was to analyze whether chemical and morphological differences contribute to differentiate A. emarginata 'terra-fria' from A. emarginata 'mirim', as chemophenetic variations of A. emarginata. The analysis of chemical compounds was based on the quantification, profile of root alkaloids and on the leaves volatile profile, together with morphometric analyses of the leaf blade. The samples were collected in three phenological stages (flowering, fruiting, and vegetative) at two places in São Paulo, Brazil. Differences in the composition of the alkaloid profile and leaf volatiles (in both places and in the three phenological stages) allowed us to separate the two morphotypes by multivariate statistical analysis. These differences agreed with the leaf blade morphology and flower color. This first chemophenetic report of A. emarginata demonstrates that, in addition to morphological variations, the specialized metabolism of roots and leaves can be phytochemical characters, which suggest the existence of at least morphochemotypes of A. emarginata.

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Wheat is one of the most important crops in Argentina and worldwide. One of the major diseases affecting the crop is the Fusarium Head Blight (FHB). It is an endemic disease caused mainly by Fusarium graminearum, the most common agent of FHB around the world. The infection is strongly influenced by environmental parameters and occurs mostly when there are favourable conditions of moisture and temperature during wheat anthesis or flowering. This destructive disease affects wheat, barley and other small grains and has the capability of destroying crops, causing great economic losses due to reduced grain quality, and the accumulation of significant levels of mycotoxins such as trichothecenes. The aim of this study was to evaluate the influence of temperature on mycotoxin biosynthesis, on three strains of F. graminearum of 15-ADON genotype and one of 3-ADON genotype, with different capacity of synthesizing DON, 3-ADON and 15-ADON. Trichothecene production of the strains at different temperatures (5, 10, 15, 20, 25, 30 and 35 °C) was evaluated after 7, 14, 21, 28 and 35 d of incubation. The optimum temperature to produce DON and 3-ADON was between 25 and 30 °C, but the maximum production of 15-ADON occurred at a lower temperature (10 °C) for all the strains. Conversely, the minimum production of DON and 3-ADON was recorded between 5 and 10 °C and of 15-ADON between 30 and 35 °C. A possible explanation for the similar accumulation of both acetyl derivatives by strains of different chemotype and genotypes could be that the acetyl derivatives biosynthesis is regulated by temperature.

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The chemical composition of volatile oil extracted from leaves of two morphotypes of Psidium cattleyanum Sabine from southern Brazil was evaluated at four phenological stages. In addition, plant material was evaluated at four different locations of the Planalto Serrano Region of Santa Catarina state, Brazil. Major components found were: 1,8-cineole, α-pinene, α-eudesmol, (E)-caryophyllene and p-cymene in red morphotype whereas 1,8-cineole, α-pinene, myrcene, (E)-caryophyllene and valerianol were found in the yellow morphotype. The differences observed in the chemical composition in red and yellow morphotypes may help in the differentiation between the two morphotypes in the absence of fruits. Also, important differences were observed mainly for 1,8-cineole and α-pinene percentage at different phenological stages.

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Introduction: Lippia alba is an aromatic species belonging to the Verbenaceae family. Its essential oils have been used in different industries, because of its biological properties. Objective: Identify the perspectives of the biotechnological applications of Lippia alba essential oils. Methodology: A scoping review was conducted on the biological activity of Lippia alba essential oils registered until October, 2018 in EBSCO, Embase, Pubmed, Scopus, SciELO, and Lilacs databases. Results: Chemotypes I and III have been reported for different biological activities from the evaluations performed on microorganisms, fish, arthropods, small mammals, and cell lines; fundamentally associated with antibacterial, antifungal, cytotoxic, antioxidant, and sedative effects, among others. Records focused mainly on the health, fishing industry, and agrifood sectors. Conclusion: Studies on the effect of essential oil are promising, but do not reflect a continuity of the research toward prototypes or finished commercial products. Research groups must unify evaluation methodologies and include in all studies the relationship between phytochemical and biological activity for the meta-analyses to be possible. Likewise, they must join efforts through the National System for Agricultural Innovation (SNIA, for the term in Spanish) to generate finished products that impact upon society and facilitate progress in the country's bio-economy.

Introducción: Lippia alba es una especie aromática perteneciente a la familia Verbenaceae, cuyos aceites esenciales han sido empleados en diferentes industrias dada sus propiedades biológicas. Objetivo: Identificar las perspectivas de aplicación biotecnológica de los aceites esenciales de Lippia alba. Métodos: Se realizó una revisión sistemática exploratoria de la literatura sobre la actividad biológica de aceites esenciales de Lippia alba registrada hasta octubre 2018 en las bases de datos EBSCO, Embase, Pubmed, Scopus, SciELO, y Lilacs. Resultados: Los quimiotipos I y III han sido reportados para diferentes actividades biológicas a partir de evaluaciones realizadas en microorganismos, peces, artrópodos, pequeños mamíferos, y líneas celulares; fundamentalmente asociadas con efectos antibacterial, antifúngico, citotóxico, antioxidante y sedante, entre otros. Los registros se enfocaron principalmente a los sectores salud, industria pesquera y agroalimentaria. Conclusión: Los estudios sobre el efecto del aceite esencial son promisorios, pero no reflejan una continuidad de la investigación hacia prototipos o productos comerciales acabados. Los grupos de investigación deben unificar metodologías de evaluación e incluir en todos los estudios la relación entre fitoquímica-actividad biológica, para que los metaanálisis sean posibles. De igual manera, deben aunar esfuerzos por medio del Sistema Nacional de Innovación Agropecuaria (SNIA), para generar productos acabados que impacten en la sociedad y faciliten el avance de la bioeconomía del país.

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BACKGROUND: Widespread commercialization of cannabis has led to the introduction of brand names based on users' subjective experience of psychological effects and flavors, but this process has occurred in the absence of agreed standards. The objective of this work was to leverage information extracted from large databases to evaluate the consistency and validity of these subjective reports, and to determine their correlation with the reported cultivars and with estimates of their chemical composition (delta-9-THC, CBD, terpenes). METHODS: We analyzed a large publicly available dataset extracted from Leafly.com where users freely reported their experiences with cannabis cultivars, including different subjective effects and flavour associations. This analysis was complemented with information on the chemical composition of a subset of the cultivars extracted from Psilabs.org . The structure of this dataset was investigated using network analysis applied to the pairwise similarities between reported subjective effects and/or chemical compositions. Random forest classifiers were used to evaluate whether reports of flavours and subjective effects could identify the labelled species cultivar. We applied Natural Language Processing (NLP) tools to free narratives written by the users to validate the subjective effect and flavour tags. Finally, we explored the relationship between terpenoid content, cannabinoid composition and subjective reports in a subset of the cultivars. RESULTS: Machine learning classifiers distinguished between species tags given by "Cannabis sativa" and "Cannabis indica" based on the reported flavours: = 0.828 ± 0.002 (p < 0.001); and effects: = 0.9965 ± 0.0002 (p < 0.001). A significant relationship between terpene and cannabinoid content was suggested by positive correlations between subjective effect and flavour tags (p < 0.05, False-Discovery-rate (FDR)-corrected); these correlations clustered the reported effects into three groups that represented unpleasant, stimulant and soothing effects. The use of predefined tags was validated by applying latent semantic analysis tools to unstructured written reviews, also providing breed-specific topics consistent with their purported subjective effects. Terpene profiles matched the perceptual characterizations made by the users, particularly for the terpene-flavours graph (Q = 0.324). CONCLUSIONS: Our work represents the first data-driven synthesis of self-reported and chemical information in a large number of cannabis cultivars. Since terpene content is robustly inherited and less influenced by environmental factors, flavour perception could represent a reliable marker to indirectly characterize the psychoactive effects of cannabis. Our novel methodology helps meet demands for reliable cultivar characterization in the context of an ever-growing market for medicinal and recreational cannabis.

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The Lippia alba species consists of an aromatic plant used in Brazilian traditional medical practice and in the medical practice of several countries as well. Presenting a wide variability in its essential oil chemical composition, the Lippia alba is classified in chemotypes, or chemical races, according to the major constituents contained in its essential oil. Considering the quali and quantitative distribution of the components in the essential oil affect directly its pharmacological properties, which are presented in the medicinal species, this paper proposes a scientific literature review to correlate both biological and pharmacological properties presented by L. alba according to its chemical constitution.

Lippia alba es una planta aromática utilizada en la medicina tradicional de Brasil y de varios países. Con una gran variabilidad en la composición química de su aceite esencial, se clasifica en quimiotipos, o razas químicas, de acuerdo con los constituyentes mayoritarios presentes en el aceite esencial. Dado que la distribución cualitativa y cuantitativa de los componentes del aceite esencial afecta directamente a las propiedades farmacológicas presentadas por la especie medicinal, este trabajo propone realizar una revisión en la literatura científica para correlacionar las propiedades biológicas y farmacológicas de los quimiotipos presentes en el aceite essencial de la L. alba.

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Lippia alba is a popular Brazilian herb known as 'cidreira' that presents several chemotypes which exhibit different chemical profile and they are widely used as seasonings and traditional medicine. This work describes the seasonal variation of metabolites of polar extracts of carvone and linalool chemotypes, identified by GC-MS analyses of the essential oils. A methodology was elaborated in order to obtain a seasonal variation in the chemical composition of leaf employing HPLC-DAD. Acteoside, isoacteoside, geneposidic acid, 8-epi-loganin, mussaenoside, luteolin 7-O-glucoside, apigenin 7-O-glucuronide and tricin 7-O-diglucuronide have been isolated and identified for validation procedures and chromatographic analysis. Geneposidic acid was presented in all samples, in contrast to the 8-epi-loganin and, mussaenoside which were presented only in the carvone-chemotype. Acteoside was the major metabolite detected from July to November while tricin-7-O-diglucuronide was the major compound in all other months. Besides, phenylpropanoids are predominant in winter and flavonoids in summer season.

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The essential oil of Psidium guajava L. has been studied for pharmacological and industrial purposes, without considering the plant's genotype regarding the heterogeneity of its composition. The present study aimed to characterize the chemotype diversity of the essential oil extracted from the leaves of 22 genotypes of P. guajava grown in two different environments in the state of Espírito Santo, Brazil, and to identify the different chemical markers present in these plants. Essential oil from the leaves of the P. guajava genotypes was extracted by hydrodistillation, and its chemical composition was analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Thirty-three compounds were identified, comprising 87.5-99.0% of the total composition, with a prevalence of sesquiterpenes in all samples. The major compounds identified consisted of (E)-trans-Caryophyllene, α-Humulene, trans-Nerolidol, ß-Bisabolene, ß-Bisabolol, and Hinesol, the first of which was identified as a possible chemical marker for the species. Multivariate factor analysis of the chemical composition of P. guajava oil identified three chemotypes: Commercial - PAL, SEC, PS, PET, C7, C11, and C17MI, characterized by high levels of ß-Selinene, α-Selinene, Hinesol, and 14-hydroxy-epi-(E)-caryophyllene, with ß-Selinene and α-Selinene as the chemical markers; C10 and C13, exhibiting high levels of Elemol, trans-Nerolidol, trans-ß-Eudesmol, and (2Z, 6Z)-Farnesol, which were indicated as chemical markers, and Cortibel - C1, C2, C3, C4, C5, C6, C8, C9, C12, C14, C15, C16, C17LI, which retained high levels of α-Cedrene, cis-α-Bergamotene, α-Humulene, Humulene epoxide, epi-α-Cadinol, ß-Bisabolol, and α-Bisabolol, with ß-Bisabolol and α-Bisabolol as the chemical markers. The use of guava genotypes with different chemotypes, that are agronomically favorable to fruit production and essential oil exploitation adds value to the crop and renders it more sustainable. Given guava crops produce large amounts of leaf biomass, resulting from successive prunings, the extraction of their essential oil, which retains commercially valuable compounds, can be feasible.

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ABSTRACT Tithonia diversifolia (Hemsl.) A. Gray, Asteraceae, commonly known as Mexican sunflower, is a wide distributed invasive species encountered around the world. We proposed herein to establish the relationship between different abiotic environmental factors and the variation in the production of volatile compounds in T. diversifolia, during a period of one year. Samples of leaf and inflorescence volatile oils obtained from individuals located at two different regions of Brazil were analyzed by GC-MS and the data were submitted to chemometric analysis. Based on the main constituents, the analysis allowed us to classify the volatile oils into two chemotypes, according to their geographical origin. The influence of soil nutrients, mainly Ca and P, was also observed in the composition of the volatile oils. Climate also seems to affect the constituents of the volatile oils, mainly the contents of leaf sesquiterpenes of individuals growing in areas with higher average temperatures and solar radiation levels. We can therefore highlight that the appropriate multivariate statistical analysis allowed us to propose for the first time the existence of chemotypes for the volatile oils of T. diversifolia, as well as reporting the main abiotic environmental factors related to the accumulation of the discriminant compounds in these oils.

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The Verbenaceae family includes 2600 species grouped into 100 genera with a pantropical distribution. Many of them are important elements of the floras of warm-temperature and tropical regions of America. This family is known in folk medicine, and its species are used as digestive, carminative, antipyretic, antitussive, antiseptic, and healing agents. This review aims to collect information about the essential oils from the most reported species of the Verbenaceae family growing in South America, focusing on their chemical composition, antimicrobial activity, and synergism with commercial antimicrobials. The information gathered comprises the last twenty years of research within the South American region and is summarized taking into consideration the most representative species in terms of their essential oils. These species belong to Aloysia, Lantana, Lippia, Phyla, and Stachytarpheta genera, and the main essential oils they contain are monoterpenes and sesquiterpenes, such as ß-caryophyllene, thymol, citral, 1,8-cineole, carvone, and limonene. These compounds have been found to possess antimicrobial activities. The synergism of these essential oils with antibiotics is being studied by several research groups. It constitutes a resource of interest for the potential use of combinations of essential oils and antibiotics in infection treatments.

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Los aceites esenciales (AEs), pertenecientes al género Lippia, son candidatos interesantes de formulaciones tópicas en el tratamiento de la leishmaniasis cutánea (LC). El objetivo de este trabajo fue determinar el perfil toxicológico y la actividad anti-Leishmania de AEs obtenidos de plantas colombianas del género Lippia. Ratones BALB/c fueron tratados tópica u oralmente con AEs obtenidos de L. alba quimiotipo citral (AE1) y de L. origanoides quimiotipos timol (AE2), carvacrol (AE3) y felandreno (AE4). El efecto del tratamiento en la irritación de la piel, la toxicidad aguda oral, la genotoxicidad (prueba cometa y micronúcleos), los cambios en la función hepática y renal, la inducción de reacción de hipersensibilidad de contacto y en la actividad contra L. (V) panamensis y L. (V.) braziliensis fueron determinados. Todos los AEs presentaron un perfil toxicológico similar a los parámetros normales, exceptuando los aceites AE2 y AE3 los cuales fueron irritantes y presentaron algunos signos de toxicidad aguda oral al ser utilizados en altas concentraciones (concentraciones bajas no fueron tóxicas). El AE2 mostró actividad antiparasitaria en las formas parasitarias evaluadas. Concentraciones bajas de los AEs podrían utilizarse de forma segura como componentes de formulaciones farmacológicas en LC.

Essential oils (EOs) belonging to the genus Lippia are interesting candidates in pharmaceutical systems for cutaneous leishmaniasis (CL). The aim of this work was to determine both toxicological and antileishmanial activities of EOs obtained from different species of Lippia, a widely distributed Colombian plants. BALB/c mice were treated topically or orally with EOs obtained from L. alba citral chemotype (EO1) and L. origanoides thymol (EO2), carvacrol (EO3) and phellandrene (EO4) chemotypes. The skin irritation, oral acute toxicity, genotoxicity (comet assay and micronucleus test), liver and renal adverse effects, All the EOs showed a toxicological profile similar to the normal parameters, except for oils EO2 and EO3 which were irritant and showed some signs of acute oral toxicity at high concentrations (low concentration were safe). The EO2 showed antiparasitic activity. Low concentrations of the EO could be used safely as components of pharmacological formulations in CL.

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BACKGROUND: Avicennia schaueriana Stapf & Leechm. ex Moldenke (Acanthaceae) is a native species from the Brazilian mangroves presenting ecological and economic significance. This study compared the composition and the biological activities from the essential oils obtained from two A. schaueriana populations collected at Jureia-Itatins and Ilha do Cardoso. METHODS: Essential oils were obtained by conventional means, and their compositions were analyzed by GC-MS. Screening assays for antimicrobial activity were carried out by the microdilution method and the antioxidant potential was assessed by the DPPH scavenging method. RESULTS: The GC-MS analysis indicated that the Jureia oil (1) was composed mostly of the fatty acids palmitic (46.5%) and myristic (11.6%) acids, while the main components for the Ilha do Cardoso oil (2) were eugenol (19.7%), eugenol acetate (12.9%) and palmitic acid (15.1%). The oils showed an IC50 of 0.9 ± 0.011 mg/mL for 1 and 1.13 ± 0.028 mg/mL for 2 in the DPPH assay. The antimicrobial assay indicated MIC > 217 µg/mL for all tested microorganisms. CONCLUSIONS: The different essential oil composition may indicate the presence of chemotypes for A. schaueriana. The antioxidant activity of the oils was weak if compared with flavonoids. Despite the high MIC values, these oils presented some antibacterial potential against Pseudomonas aeruginosa.

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Background: The challenge in antimicrobial chemotherapy is to find safe and selective agents with potency that will not be compromised by previously developed resistance. Terrestrial plants could provide new leads to antibacterial, antifungal, or antiprotozoal activity. Methods: The essential oil (EO) of Piper aduncum L. (Piperaceae) from Cuba was analyzed by gas chromatography-mass spectrometry (GC-MS). A cluster analysis of P. aduncum EO compositions reported in the literature was carried out. The EO was screened against a panel of microorganisms (bacteria, fungi, parasitic protozoa) as well as for cytotoxicity against human cells. In addition, a review of scientific literature and a bibliometric study was also conducted. Results: A total of 90 compounds were identified in the EO, of which camphor (17.1%), viridiflorol (14.5%), and piperitone (23.7%) were the main components. The cluster analysis revealed at least nine different chemotypes. The EO did not show notable activity against bacteria or fungi, but was active against parasitic protozoa. Conclusions: The results from this study indicate P. aduncum from Cuba is a unique chemotype, support the importance of P. aduncum EOs as medicines, and demonstrate the promise of Cuban P. aduncum EO as a chemotherapeutic agent against parasitic protozoal infections.

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The chemical composition of the essential oil of Kurzamra pulchella (Lamiaceae) was determined. Twelve compounds were identified, with isomenthone (60.6%) and pulegone (37.1%) predominating. Chemotaxonomical considerations were discussed.

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Recent studies on a field population of F. graminearum sensu stricto from Argentina revealed an atypical panel of strains identified through PCR genotyping as 15ADON genotypes, but producing high levels of 3ADON. Based on representative strain CBS 139514, we asked if the discrepancy between the trichothecene genotype and chemotype might result from an inter-chemotype recombination of the chemotype-determining genes. To answer this, we sequenced the complete core Tri gene cluster (around 30,200 bp) from this strain and compared its sequence to sequence data of typical type B trichothecene genotypes/chemotypes. Sequence alignment showed that CBS 139514 has an identical sequence within the entire core Tri cluster to the 15ADON genotype. The revealed discrepancy underlines the need for using both molecular and chemical methods for reliable characterization of toxigenic strains of Fusarium.

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Aedes aegypti L. (Díptera: Culicidae), es vector de los virus que provocan las enfermedades febriles Dengue, Chikungunya y Zika, que afectan a gran parte de la población en los países tropicales, por lo que la búsqueda de nuevos plaguicidas naturales constituye un recurso importante para combatir a este mosquito. En el presente estudio se evaluaron cinco aceites esenciales obtenidos de tres quimiotipos de Lippia graveolens Kunth. (timol, carvacrol y mixto) y dos de Lippia alba (Mill.) N.E.Br. ex Britton & P. Wilson (citral y carvona), como alternativa para disminuir el impacto ambiental, del uso de insecticidas químicos para el control de las larvas del mosquito. Se realizaron bioensayos para cada uno de las cuatro estadios larvarios, en un diseño experimental completamente al azar con cuatro repeticiones, empleando cuatro concentraciones de los aceites esenciales (0.4, 0.2, 0.1 y 0.05 mg/mL); la lectura de mortalidad se hizo a las 24 h de exposición y se determinó la concentración letal media (CL50). En los cuatro estadios larvarios, el aceite esencial obtenido del quimiotipo timol de L. graveolens, mostró las CL50 más bajas con las mayores mortalidades: primer estadio, 0.056 mg/mL 95% IC [0.046, 0.064]; segundo estadio 0.068 mg/mL 95% IC [0.062, 0.077]; tercer estadio, 0.088 mg/mL 95% IC [0.080, 0.096]; cuarto estadio, 0.092 mg/mL 95% IC [0.084, 0.100]. Estos resultados sugieren el potencial uso del aceite esencial quimiotipo timol, como un insecticida de origen natural, para el control de A. aegypti.

Aedes aegypti L. (Díptera: Culicidae), is a vector of the viruses that cause febrile illnesses such as Dengue, Chikungunya and Zika, which affect in large extent the population of tropical countries, thus, the search of pesticides of natural origin is an important resource to combat this mosquito. In this study five essential oils, obtained from three chemotypes of Lippia graveolens Kunth. (thymol, carvacrol and mixed) and two of Lippia alba (Mill.) N.E.Br. ex Britton & P. Wilson (citral and carvone), were evaluated as an alternative to chemical pesticides to reduce the environmental impact, in order to control the insect larvae. Bioassays were performed randomly for each of the four instars in an experimental design with four replications, using four concentrations of the essential oils (0.4, 0.2, 0.1 and 0.05 mg / mL); the mortality reading was recorded after 24 hours of exposure and the median lethal concentration (LC50) was determined.. In all larval stages, the essential oil obtained from L. graveolens thymol chemotype showed the lowest LC50 with the highest mortality rate: first instar, 0.056 mg/mL 95 % CI ([0.046, 0.064]); second instar, 0.068 mg/ mL 95 % CI [0.062, 0.077]; third instar, 0.088 mg/mL 95 % CI [0.080, 0.096]; fourth instar, 0.092 mg/mL 95 % CI [0.084, 0.100]. These results suggest the potential use of the essential oil thymol chemotype, as an insecticide of natural origin, to control A. aegypti.