199 research outputs found
Uso de sesquiterpenos eremofilanos como garrapaticidas
Uso de al menos un sesquiterpeno eremofilano de
fórmula (I) como garrapaticida, donde R1
es H o OH;
[1] es un enlace simple o doble; X se selecciona del
grupo que consiste en ausente, CH3, OH, OOH y junto
a Z forma un epóxido de estructura (Z-IV); y Z se
selecciona del grupo que consiste en (Z-I), (Z-II), (Z-III)
y junto a X forma (ZIV), preferiblemente el
sesquiterpeno (I) es dehidrofukinona, 11-
hidroxieremofil-6(7), 9(10)-dien-8-ona, 7-11-
epoxieremofil-9(10)-en-8-ona, o una mezcla.
Preferiblemente el sesquiterpeno actúa frente a
garrapatas del género Hyalomma spp. y/o
Rhipicephalus spp. En particular, uso para tratar o
prevenir una enfermedad causada por garrapatas en
un humano o animal; y uso para prevenir, controlar o
eliminar la presencia de garrapatas en el entorno en
contacto con un animal o humano. Así como un
producto que comprende dicho sesquiterpeno de
fórmula (I)Peer reviewedConsejo Superior de Investigaciones Científicas, Universidad Complutense de Madrid, Universidad de Santiago de ChileB1 Patente sin examen previ
Sesquiterpene lactones from artemisia absinthium. Biotransformation and rearrangement of the insect antifeedant 3α-hydroxypelenolide
Three new compounds, the sesquiterpenes absilactone and hansonlactone and the acetophenone derivative ajenjol, have been isolated from a cultivated variety of Artemisia absinthium. In addition, the major lactone isolated, 3α-hydroxypelenolide, was biotransformed by the fungus Mucor plumbeus affording the corresponding 1β, 10α-epoxide. A cadinane derivative was formed by an acid rearrangement produced in the culture medium, but not by the enzymatic system of the fungus. Furthermore, 3α-hydroxypelenolide showed strong antifeedant effects against Leptinotarsa decemlineata and cytotoxic activity to Sf9 insect cells, while the biotransformed compounds showed antifeedant postingestive effects against Spodoptera littoralis.This work has been supported by grants ERASMUS+ Nº 2018-1-FR01-KA202-047892
Biocontrol E Training (BET) and PID2019-106222RB-C31, MCI, Spai
Artemisia thuscula Cav.: antibacterial, antifungal activity of the plant extracts and associated endophytes
4 páginas, 2 tablas.In this paper we are presenting preliminary results for the antifungal and antibacterian activity of the Artemisia thuscula Cav. all together with the endophytic communities encountered in symbiosis with this specie. This plant is endemic for the Canary Islands and it is recognised for its traditional medicinal use (like other species of the same genus in the rest of the world) and for being a functional repellent of insects.
The ethanol extracts tested showed an interesting activity against the phytopathogenic fungi Fusarium monilforme, F. solani and F. oxysporum and antibiotic activity against 2 Gram-positive bacteria: Bacillus cereus and Streptomyces griseus, in an primary screening.
The diversity of endophytes found in this plant, especially in the roots, showed promising results supporting further work on this species.This publication has been financed by the project:
‘Bioprospection of endophytes in medicinal plants for biopesticides production’ MCIN- FCCI. 2009. Ref. ACI2009-0900Peer reviewe
Antiparasitic properties of cantharidin and the blister beetle berberomeloe majalis (Coleoptera: Meloidae)
Cantharidin (CTD) is a toxic monoterpene produced by blister beetles (Fam. Meloidae) as a chemical defense against predators. Although CTD is highly poisonous to many predator species, some have evolved the ability to feed on poisonous Meloidae, or otherwise beneficially use blister beetles. Great Bustards, Otis tarda, eat CTD-containing Berberomeloe majalis blister beetles, and it has been hypothesized that beetle consumption by these birds reduces parasite load (a case of self- medication). We examined this hypothesis by testing diverse organisms against CTD and extracts of B. majalis hemolymph and bodies. Our results show that all three preparations (CTD and extracts of B. majalis) were toxic to a protozoan (Trichomonas vaginalis), a nematode (Meloidogyne javanica), two insects (Myzus persicae and Rhopalosiphum padi) and a tick (Hyalomma lusitanicum). This not only supports the anti-parasitic hypothesis for beetle consumption, but suggests potential new roles for CTD, under certain conditions.This research was funded by MINECO/FEDER, Spain, Grant no. CTQ2015-64049-C3-1-R; Ministerio de Economía y Competitividad, Spain (MINECO/FEDER), Grant no. CGL2017-87206-
Adaptation of the colorimetric MTT assay for evaluating activity against Giardia duodenalis
Giardia duodenalis es un parásito protozoario flagelado cosmopolita con un amplio rango de hospedadores, incluyendo tanto animales domésticos como salvajes, así como al ser humano. Se reproduce en el intestino delgado ocasionando giardiosis, enfermedad caracterizada por producir diarrea, cólicos abdominales, pérdida de peso y malabsorción. El presente trabajo tiene como objetivo la estandarización del método colorimétrico del MTT (bromuro de 3-(4,5- dimetiltiazol-2-ilo)-2,5-difeniltetrazol) para la realización de ensayos de actividad in vitro frente a trofozoítos de G. duodenalis. El MTT ha demostrado ser útil en la determinación de productos activos frente a diversos biomodelos y un buen sustituto del recuento microscópico en la determinación de la viabilidad de los parásitos. Para adaptar este método a G. duodenalis se realizaron una serie de ensayos a fin de optimizar la prueba, empezando con la realización de curvas de crecimiento para observar el comportamiento de los cultivos de este protozoario. Además, se realizaron otros ensayos modificando ciertas variables como el inóculo inicial, la fase del cultivo o las concentraciones de reactivos, dando como resultado un protocolo efectivo estandarizado. Los resultados de este estudio pueden ser de gran utilidad para identificar compuestos con actividad frente a G. duodenalis.dengue, pero ¿cómo explicar la desatención de esa virosis por el conocimiento público en 2023?Giardia duodenalis is a cosmopolitan flagellated protozoan parasite with a wide range of hosts, including both domestic and wild animals, as well as humans. It reproduces in the small intestine causing giardiosis, a disease characterized by diarrhea, abdominal cramps, weight loss, and malabsorption. The aim of this study is to standardize the colorimetric MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method for in vitro assays against G. duodenalis trophozoites. The MTT has been shown to be useful in determining active products against various biomodels and a good substitute for microscopic counting in determining parasite viability. To adapt this method to G. duodenalis, a series of assays were performed to optimize the test, starting with growth curves to observe the behavior of the protozoan cultures. Multiple assays were then performed, modifying certain variables such as initial inoculum, culture phase, or reagent concentrations, resulting in an effective standardized protocol. The results of this study can be of great utility in identifying compounds with activity against G. duodenalis.Asociación Parasitológica Argentin
Valorization of the Sabinas Forest Waste (Juniperus phoenicea and Juniperus thurifera) as Source of Biopesticides
Objectives: The potential forestry use of Juniperus phoenicea and Juniperus thurifera pruning woods is studied by analyzing the composition of the woods and testing the biological activities of the corresponding components with the ultimate target of finding new biopesticides. Methods: The air-dried wood from each plant was crushed and subjected to hydrodistillation, and the residue was extracted with a Soxhlet apparatus using different solvents. The corresponding extracts were fractionated, and their composition were studied by gas chromatography-mass spectrometry and nuclear magnetic resonance techniques. The ixodicidal and antifungal activities of the different samples obtained were evaluated. Results: The fraction oxygenated of the essential oil from both J. thurifera (cedrol >60%) and J. phoenicea shows a remarkable bioactivity as antitick with EC50 values of 3.4 μg/mg and 10 μg/mg, respectively. Cedrol and methyl hinokiate, present in the hexane extract J. thurifera, show a potent antifungal effect against Aspergillus niger with EC50 values of 45.99 and 52.23 μg/mL, respectively. Conclusions: Pruning woods from these species proved to be renewable and easily accessible sources of bioactive natural products such as cedrol, thujopsene, nootkatone, and totarol.MINISTERIO de CIENCIA e
INNOVACIÓN, PID2019-106222RB-C31/SRA, PID2019-106222RBC32/
SRA (State Research Agency, 10.13039/501100011033)Unidad
Asociada UGR-CSIC Bioplaguicidas: Biotecnología, Síntesis y Diversidad
químic
Antifungal Effect of Essential Oils
Essential oils are employed in agriculture, medicine and food industries among others, due to their antimicrobial, antiviral, insecticidal and antifungal properties. In this chapter, we will focus on the control of fungal plant pathogens with essential oils. Fungal diseases in agricultural crops and forestry alter the physiology of plants, disrupting their normal functioning, reducing their yield and sometimes causing their death. Recent studies show antifungal effects of many essential oils against plant pathogenic fungi, which make them candidates for the development of new fungicidal agents. This chapter presents a review of the most recent advances in this area, as well as the future trends in this field
Article Germacrone Derivatives as new Insecticidal and Acaricidal Compounds: A Structure-Activity Relationship
The supplementary material related to this article includes NMR spectra of new compounds is available online at https://www.mdpi.com/1420-3049/24/16/2898/s1.Currently, the use of synthetic pesticides is the main method of plant protection applied in agri- and horticulture. However, its excessive use leads to the development of pesticide resistance, a contamination of the environment, toxicity to non-target organisms, and risks for human health. With the ultimate aim of contributing to the develop of a more sustainable pest management, we used the natural product germacrone (compound 1), reported to possess significant insecticidal activity, as starting material for the generation of molecular diversity (2–24). Some of the generated derivatives are natural compounds, such as 1,10-epoxygermacrone (2), 4,5-epoxygermacrone (3), gajutsulactone A (7), germacrol (11), isogermacrone (14), 9-hydroxyeudesma-3,7(11)dien-6-one (19), eudesma-4,7(11),dien-8-one (20), eudesma-3,7(11)-dien-8-one (21) and eudesma-4(15),7(11)-dien-8-one (22). Compounds, 7,11-9,10-diepoxigermacr-4,5-en-8-ol (17), 7,11-epoxieudesma-4,7(11)-dien-8-one (23) and 7,11-epoxieudesma-3,7(11)-dien-8-one (24) are described for the first time. The biocidal activity of most of these compounds was assayed against the tick Hyalomma lusitanicum. The acaricidal effects of compound 24 were four times higher than that of germacrone (1). Compound 2 is an insect antifeedant a thousand times more potent than germacrone against Rhopalosiphum padi, which makes this substance a promising selective antifeedant against this cereal pest.This research was funded by Grant CTQ-2015-64049-C3-3-R/CTQ2015-64049-C3-1-R; MINISTERIO DE ECONOMÍA Y COMPETITIVIDAD, Spain (MINECO/FEDER)
Acaricidal and Repellent Effects of Essential Oils against Ticks: A Review
17 Pág.
Departamento de Reproducción AnimalTick control is a priority in order to prevent the transmission of vector-borne diseases. Industrial chemical acaricides and repellents have been the most efficient tools against hard ticks for a long time. However, the appearance of resistances has meant the declining effectiveness of the chemicals available on the market. The trend today is to develop alternative control methods using natural products to replace nonefficient pesticides and to preserve the efficient ones, hoping to delay resistance development. Traditional in vitro evaluation of acaricidal activity or resistance to synthetic pesticides have been reviewed and they mainly focus on just one species, the one host tick (Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)). Recent reports have called for the standardization of natural product components, extraction techniques, and experimental design to fully discover their acaricidal potential. This study reviews the main variables used in the bibliography about the efficiency of natural products against ticks, and it proposes a unification of variables relating to ticks, practical development of bioassays, and estimation of ixodicidal activity.This study was funded by Villamagna S.A.Peer reviewe
Anti-Trypanosomatidae Activity of Essential Oils and Their Main Components from Selected Medicinal Plants
Kinetoplastida is a group of flagellated protozoa characterized by the presence of a kinetoplast, a structure which is part of a large mitochondria and contains DNA. Parasites of this group include genera such as Leishmania, that cause disease in humans and animals, and Phytomonas, that are capable of infecting plants. Due to the lack of treatments, the low efficacy, or the high toxicity of the employed therapeutic agents there is a need to seek potential alternative treatments. In the present work, the antiparasitic activity on Leishmania infantum and Phytomonas davidi of 23 essential oils (EOs) from plants of the Lamiaceae and Asteraceae families, extracted by hydrodistillation (HD) at laboratory scale and steam distillation (SD) in a pilot plant, were evaluated. The chemical compositions of the EOs were determined by gas chromatography-mass spectrometry. Additionally, the cytotoxic activity on mammalian cells of the major components from the most active EOs was evaluated, and their anti-Phytomonas and anti-Leishmania effects analyzed. L. infantum was more sensitive to the EOs than P. davidi. The EOs with the best anti-kinetoplastid activity were S. montana, T. vulgaris, M. suaveolens, and L. luisieri. Steam distillation increased the linalyl acetate, β-caryophyllene, and trans-α-necrodyl acetate contents of the EOs, and decreased the amount of borneol and 1,8 cineol. The major active components of the EOs were tested, with thymol being the strongest anti-Phytomonas compound followed by carvacrol. Our study identified potential treatments against kinetoplastids.Publishe
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