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1.
Phytochemistry ; 215: 113838, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37648046

RESUMEN

Six different furanocoumarins were isolated from the aerial parts of Ducrosia anethifolia and tested in vitro for plant cell elongation in etiolated wheat coleoptile. They were also tested for their ability to control three different weeds: ribwort plantain, annual ryegrass, and common purslane. These compounds exhibited strong inhibition of plant cell elongation. In the case of (+)-heraclenin, the IC50 was lower than 20 µM, indicating a better inhibition than the positive control Logran®. Computational experiments for docking and molecular dynamics revealed for the investigated furanocoumarins bearing an epoxide moiety an improved fitting and stronger interaction with the auxin-like TIR1 ubiquitin ligase. Furthermore, the formed inhibition complex remained also stable during dynamic evaluation. Bidental interaction at the active site, along with an extended hydrogen-bond lifetime, explained the enhanced activity of the epoxides. The in vitro weed bioassay results showed that Plantago lanceolata was the most affected weed for germination, root, and shoot development. In addition, (+)-heraclenin displayed better inhibition values than positive control even at 300 µM concentration.


Asunto(s)
Apiaceae , Fabaceae , Furocumarinas , Oryza , Oryza/química , Productos Agrícolas , Extractos Vegetales/farmacología , Verduras , Malezas
2.
J Agric Food Chem ; 70(12): 3644-3653, 2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35289164

RESUMEN

The encapsulation of bioactive natural products has emerged as a relevant tool for modifying the poor physicochemical properties often exhibited by agrochemicals. In this regard, natural guaiane-type sesquiterpene lactones isolated from Cynara cardunculus L. have been encapsulated in a core/shell nanotube@agrochemical system. Monitoring of the F and O signals in marked sesquiterpenes confirmed that the compound is present in the nanotube cavity. These structures were characterized using scanning transmission electron microscopy-X-ray energy-dispersive spectrometry techniques, which revealed the spatial layout relationship and confirmed encapsulation of the sesquiterpene lactone derivative. In addition, biological studies were performed with aguerin B (1), cynaropicrin (2), and grosheimin (3) on the inhibition of germination, roots, and shoots in weeds (Phalaris arundinacea L., Lolium perenne L., and Portulaca oleracea L.). Encapsulation of lactones in nanotubes gives better results than those for the nonencapsulated compounds, thereby reinforcing the application of fully organic nanotubes for the sustainable use of agrochemicals in the future.


Asunto(s)
Cynara , Nanotubos , Cynara/química , Lactonas/química , Lactonas/toxicidad , Extractos Vegetales/química , Extractos Vegetales/farmacología , Sesquiterpenos de Guayano
3.
Plant Cell Environ ; 45(2): 512-527, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34719040

RESUMEN

Nitrogen (N) and phosphorus (P) are among the most important macronutrients for plant growth and development, and the most widely used as fertilizers. Understanding how plants sense and respond to N and P deficiency is essential to optimize and reduce the use of chemical fertilizers. Strigolactones (SLs) are phytohormones acting as modulators and sensors of plant responses to P deficiency. In the present work, we assess the potential role of SLs in N starvation and in the N-P signalling interplay. Physiological, transcriptional and metabolic responses were analysed in wild-type and SL-deficient tomato plants grown under different P and N regimes, and in plants treated with a short-term pulse of the synthetic SL analogue 2'-epi-GR24. The results evidence that plants prioritize N over P status by affecting SL biosynthesis. We also show that SLs modulate the expression of key regulatory genes of phosphate and nitrate signalling pathways, including the N-P integrators PHO2 and NIGT1/HHO. The results support a key role for SLs as sensors during early plant responses to both N and phosphate starvation and mediating the N-P signalling interplay, indicating that SLs are involved in more physiological processes than so far proposed.


Asunto(s)
Compuestos Heterocíclicos con 3 Anillos/metabolismo , Lactonas/metabolismo , Nitrógeno/fisiología , Fósforo/fisiología , Transducción de Señal , Solanum lycopersicum/fisiología
4.
Molecules ; 26(17)2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-34500685

RESUMEN

Yucca is one of the main sources of steroidal saponins, hence different extracts are commercialized for use as surfactant additives by beverage, animal feed, cosmetics or agricultural products. For a deeper understanding of the potential of the saponins that can be found in this genus, an exhaustive review of the structural characteristics, bioactivities and analytical methods that can be used with these compounds has been carried out, since there are no recent reviews on the matter. Thus, a total of 108 saponins from eight species of the genus Yucca have been described. Out of these, the bioactivity of 68 saponins derived from the isolation of Yucca or other genera has been evaluated. Regarding the evaluation and quality control of the saponins from this genus LC-MS technique is the most often used. Nevertheless, the development of methods for their routine analysis in commercial preparations are needed. Moreover, most of the studies found in the literature have been carried out on Y. schidigera extract, since is the most often used for commercial purposes. Only eight of the 50 species that belong to this genus have been studied, which clearly indicates that the identification of saponins present in Yucca genus is still an unresolved question.


Asunto(s)
Saponinas/química , Yucca/química , Glicósidos/química
5.
Molecules ; 26(15)2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34361785

RESUMEN

Even today, weeds continue to be a considerable problem for agriculture. The application of synthetic herbicides produces serious environmental consequences, and crops suffer loss of their activity due to the appearance of new resistant weed biotypes. Our aim is to develop new effective natural herbicides that improve the problem of resistance and do not harm the environment. This work is focused on a bioassay-guided isolation and the characterization of natural products present in Moquiniastrum pulchrum leaves with phytotoxic activity and its preliminary application in weeds. Moquiniastrum pulchrum was selected for two reasons: it is an abundant species in the Cerrado region (the second most important ecosystem in Brazil, after the Amazon)-the explanation behind its being a dominant species is a major focus of interest-and it has traditional employment in folk medicine. Six major compounds were isolated in this plant: one flavone and five diterpenes, two of which are described for the first time in the literature. Four of the six compounds exhibited phytotoxic activity in the bioassays performed. The results confirmed the phytotoxic potential of this plant, which had not been investigated until now.


Asunto(s)
Asteraceae/química , Agentes de Control Biológico/toxicidad , Diterpenos/toxicidad , Flavonas/toxicidad , Herbicidas/toxicidad , Malezas/efectos de los fármacos , Control de Malezas/métodos , Bioensayo , Agentes de Control Biológico/química , Agentes de Control Biológico/aislamiento & purificación , Productos Agrícolas/crecimiento & desarrollo , Diterpenos/química , Diterpenos/aislamiento & purificación , Flavonas/química , Flavonas/aislamiento & purificación , Herbicidas/química , Herbicidas/aislamiento & purificación , Humanos , Estructura Molecular , Extractos Vegetales/química , Hojas de la Planta/química , Malezas/crecimiento & desarrollo
6.
J Agric Food Chem ; 69(31): 8684-8694, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34328733

RESUMEN

Piptocarpha rotundifolia (Less.) Baker stands out as one of the species with the highest frequency, density, and relative dominance in the Cerrado formations. However, no phytochemical studies have been carried out with this species to date. The aim of this study was to evaluate the phytotoxic activity of P. rotundifolia leaves in the search of new environmentally friendly tools for weed control. Thus, a wheat coleoptile and phytotoxic bioassay, using relevant agricultural weeds, was used to identify the most active extracts and fractions. The subsequent purification process allowed the isolation of 11 compounds, the phytotoxicity of which was evaluated in terms of wheat coleoptile elongation and with the most sensitive weeds. Piptocarphin A was found to be the major compound and the most active. To confirm its phytotoxic potential, the effect on Ipomea grandifolia grown in a hydroponic culture and on metaxylem cells was studied. The results obtained in this study demonstrate that the inhibitory activity displayed by P. rotundifolia leaf extract is mainly due to the presence of piptocarphin A. The phytotoxicity shown by P. rotundifolia leaf extract, and the isolated compounds, on weeds could provide new tools for weed control in agricultural fields.


Asunto(s)
Asteraceae , Control de Malezas , Fitoquímicos , Extractos Vegetales/toxicidad , Malezas
7.
Molecules ; 26(10)2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-34069113

RESUMEN

Annona cherimola Mill., or the custard apple, is one of the species belonging to the Annonaceae family, is widely used in traditional medicine, and has been reported to be a valuable source of bioactive compounds. A unique class of secondary metabolites derived from this family are Annonaceous acetogenins, lipophilic polyketides considered to be amongst the most potent antitumor compounds. This review provides an overview of the chemical diversity, isolation procedures, bioactivity, modes of application and synthetic derivatives of acetogenins from A. cherimola Mill.


Asunto(s)
Acetogeninas/química , Acetogeninas/uso terapéutico , Annona/química , Acetogeninas/aislamiento & purificación , Acetogeninas/farmacología , Anticarcinógenos/farmacología , Carbohidratos/química , Micelas , Polímeros/química
8.
Phytochem Anal ; 32(1): 38-61, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32515107

RESUMEN

INTRODUCTION: The analysis and detection of steroidal saponins is mainly performed using chromatographic techniques coupled with mass spectrometry. However, nuclear magnetic resonance (NMR) spectroscopy is a potential tool that can be combined with these techniques to obtain unambiguous structural characterisation. OBJECTIVE: This work provides a review of the carbon-13 (13 C)- and proton (1 H)-NMR spectroscopic data of aglycones from Agave saponins reported in the literature and also the development of an easy identification method for these natural products. METHODS: The database Scifinder was used for spectroscopic data collection in addition to data obtained from the Cadiz Allelopathy research group. The keywords used were Agave, spirostanic, furostanic, and saponin. RESULTS: The shielding variations produced by functional groups on the aglycone core and the structural features of the most representative aglycones from Agave species are described. The effects are additive for up to four long-range connectivities. A method for the identification of aglycones (HMAI) is proposed to classify aglycones from Agave spp. through the use of 1 H-NMR and heteronuclear multiple bond correlation (HMBC) experiments. CONCLUSIONS: The HMBC spectrum is representative of the structural features of aglycones from Agave spp. The HMBC method for aglycone identification (HMAI) method allowed the identification of pure saponins or mixtures thereof and this method can be used in combination with chromatographic techniques coupled with mass spectrometry to provide a more thorough analysis of Agave samples that contain aglycones.


Asunto(s)
Agave , Saponinas , Espectroscopía de Resonancia Magnética , Extractos Vegetales
9.
Prog Chem Org Nat Prod ; 112: 1-84, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33306172

RESUMEN

In Nature, the oldest method of communication between living systems is the chemical language. Plants, due to their lack of mobility, have developed the most sophisticated way of chemical communication. Despite that many examples involve this chemical communication process-allelopathy, there is still a lack of information about specific allelochemicals released into the environment, their purpose, as well as in-depth studies on the chemistry underground. These findings are critical to gain a better understanding of the role of these compounds and open up a wide range of possibilities and applications, especially in agriculture and phytomedicine. The most relevant aspects regarding the chemical language of plants, namely kind of allelochemicals, have been investigated, as well as their releasing mechanisms and their purpose will be described in this chapter.


Asunto(s)
Alelopatía , Fenómenos Fisiológicos de las Plantas , Feromonas
10.
J Chem Ecol ; 46(9): 871-880, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32691372

RESUMEN

Weeds have been a major threat in agriculture for several generations as they lead to decreases in productivity and cause significant economic losses. Parasitic plants are a specific type of weed causing losses in crops of great relevance. A new strategy has emerged in the fight against parasitic plants, which is called 'suicidal germination' or the 'honey-pot strategy'. Regarding the problem of weed control from an ecological point of view, it is interesting to investigate new natural compounds with allelopathic activity with the aim of developing new natural herbicides that can inhibit the growth of weeds without damaging the environment. Safflower crops have been affected by parasitic plants and weeds and, as a consequence, the secondary metabolites exuded by safflower roots have been studied. The sesquiterpene lactone dehydrocostuslactone was isolated and characterised, and the structurally related costunolide was identified by UHPLC-MS/MS in safflower root exudates. These sesquiterpene lactones have been shown to stimulate germination of Phelipanche ramosa and Orobanche cumana seeds. In addition, these compounds were phytotoxic on three important weeds in agriculture, namely Lolium perenne, Lolium rigidum and Echinochloa crus-galli. The exudation of the strigolactones solanacol and fabacyl acetate have also been confirmed by UHPLC-MS/MS. The study reported here contributes to our knowledge of the ecological role played by some secondary metabolites. Moreover, this knowledge could help identify new models for the development of future agrochemicals based on natural products.


Asunto(s)
Carthamus tinctorius/parasitología , Germinación/efectos de los fármacos , Raíces de Plantas/parasitología , Malezas/efectos de los fármacos , Control de Malezas/métodos , Alelopatía , Cromatografía Liquida , Lactonas/aislamiento & purificación , Lactonas/farmacología , Lolium/efectos de los fármacos , Lolium/crecimiento & desarrollo , Orobanche/efectos de los fármacos , Orobanche/crecimiento & desarrollo , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Exudados de Plantas/aislamiento & purificación , Exudados de Plantas/farmacología , Raíces de Plantas/química , Semillas/efectos de los fármacos , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Espectrometría de Masas en Tándem
11.
J Org Chem ; 85(11): 7322-7332, 2020 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-32349482

RESUMEN

Vladimiria souliei is a plant found in China used in traditional medicine. Recent isolation studies have led to the discovery of vlasouliolides, which are natural sesquiterpene dimers. However, the yields obtained from isolation have proven to be really low (<0.01%), greatly hindering the study of these molecules. In this work, we propose a simple synthetic route to obtain different vlasouliolides in good yields from dehydrocostuslactone and costunolide, which will lead to further bioactivity studies at a higher scale.


Asunto(s)
Asteraceae , Sesquiterpenos de Eudesmano , Sesquiterpenos , China , Lactonas , Sesquiterpenos de Guayano
12.
J Agric Food Chem ; 68(17): 4851-4864, 2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32259440

RESUMEN

Herbicides are a key element in agriculture but they do cause environmental problems and natural alternatives are being sought. In this context, invasive plants could provide an as yet unexplored source for the development of future herbicides. Urochloa humidicola has great invasive potential in Brazilian environments as it hampers the establishment of other plants. The phytotoxicity of U. humidicola root extracts has been evaluated, and the major components have been identified. The phytotoxicity of the extract was assessed in the wheat coleoptile assay on seeds of troublesome weeds and on Anadenanthera colubrina, a tree species used in ecological restoration programs. The ethyl acetate extract showed the highest activity, and the most affected weeds were E. crus-galli, M. maximus, and A. viridis with the latter weed more affected by the extract than by the herbicide Logran. Microscopic ultrastructural analysis of A. colubrina roots indicated possible signals of cell death. Seven compounds were identified in the ethyl acetate extract of which one diterpene and four saponins are new. Six of these compounds were tested in the wheat coleoptile bioassay. The most active were diterpene 1 and saponins 2, 3, and 6. The phytotoxic activity of U. humidicola explains the issues observed in ecological restoration with A. colubrina in the presence of Urochloa species, and its effect on weeds reinforces its potential use in agriculture.


Asunto(s)
Brachiaria/química , Herbicidas/farmacología , Extractos Vegetales/farmacología , Raíces de Plantas/química , Bioensayo , Brasil , Herbicidas/química , Estructura Molecular , Extractos Vegetales/química , Malezas/efectos de los fármacos , Poaceae/efectos de los fármacos
13.
Methods Mol Biol ; 2083: 199-208, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31745923

RESUMEN

Strigolactones (SLs) are a family of natural products produced by the plants as shoot branching factors and responsible for the induction of hyphal branching in arbuscular mycorrhizal (AM) fungi. They have been also used by parasitic plant seeds as stimulators of their germination as a strategy to ensure the presence of a host in the environment. For all these bioactivities, SLs have kept the attention of the researchers in the last years, increasing the number of published papers, and have opened new areas of research in the multiple roles that they play in the rhizosphere and as plant hormones. However, the low amount of them produced by plants and their rapid degradability make it crucial to develop fast analytical methods with very low limits of quantification. Herein, it is described a protocol for the development of an LC-MS/MS method for the quantification of SLs, using GR24 as IS, in roots exudates and extracts.


Asunto(s)
Compuestos Heterocíclicos con 3 Anillos/análisis , Lactonas/análisis , Fraccionamiento Químico , Cromatografía Liquida , Compuestos Heterocíclicos con 3 Anillos/química , Compuestos Heterocíclicos con 3 Anillos/aislamiento & purificación , Lactonas/química , Lactonas/aislamiento & purificación , Estructura Molecular , Extractos Vegetales/química , Raíces de Plantas/química , Plantas/química , Espectrometría de Masas en Tándem
14.
J Agric Food Chem ; 67(38): 10764-10773, 2019 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-31487158

RESUMEN

It has been hypothesized that the α-methylene-γ-lactone moiety of sesquiterpene lactones is a key unit for their bioactivity. As a consequence, modifications of these compounds have been focused on this fragment. In the work reported here, two sesquiterpene lactones, namely, dehydrocostuslactone and ß-cyclocostunolide, a eudesmanolide obtained by controlled cyclization of costunolide, were chosen for modification by Michael addition at C-13. On applying this reaction to both compounds, it was possible to introduce the functional groups alkoxy, amino, carbamoyl, hydroxy, and thiol to give products in good to high yields, depending on the base and solvent employed. In particular, the introduction of a thiol group at C-13 in both compounds was achieved with outstanding yields (>90%) and this is unprecedented for these sesquiterpene lactones. The bioactivities of the products were evaluated on etiolated wheat coleoptile elongation and germination of seeds of parasitic weeds, with significant activity observed on Orobanche cumana and Phelipanche ramosa. The structure-activity relationships are discussed.


Asunto(s)
Lactonas/química , Orobanchaceae/química , Orobanche/química , Extractos Vegetales/química , Malezas/química , Sesquiterpenos/química , Germinación , Estructura Molecular , Orobanchaceae/crecimiento & desarrollo , Orobanche/crecimiento & desarrollo , Malezas/crecimiento & desarrollo , Semillas/química , Semillas/crecimiento & desarrollo , Compuestos de Sulfhidrilo/química
15.
J Nat Prod ; 82(9): 2501-2508, 2019 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-31464436

RESUMEN

11,13-Dehydro seco-guaianolides, a particular type of sesquiterpene lactones, were synthesized from the commercially available α-santonin (11) using a facile strategy involving a high-yielding photochemical reaction. Natural products 10 and 17 from Artemisia gorgonum were synthesized in good yields. Specifically, compound 10 was obtained in five steps with an overall yield of 17%. The sesquiterpene lactones were tested in the etiolated wheat coleoptile bioassay, and the most active compounds were assayed on standard target species. Guaianolide 13 showed the highest phytotoxic activities when compared with the known herbicide Logran.


Asunto(s)
Artemisia/efectos de los fármacos , Plantas/efectos de los fármacos , Sesquiterpenos de Guayano/toxicidad , Bioensayo , Línea Celular Tumoral , Cristalografía por Rayos X , Herbicidas/química , Humanos , Estructura Molecular , Sesquiterpenos de Guayano/química , Análisis Espectral/métodos , Relación Estructura-Actividad
16.
Molecules ; 24(4)2019 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-30791447

RESUMEN

A bio-guided study of leaf extracts allowed the isolation of two new macrobicyclic hydrolysable tannins, namely merianin A (1) and merianin B (2), and oct-1-en-3-yl ß-xylopyranosyl-(1"-6')-ß-glucopyranoside (3) from Meriania hernandoi, in addition to 11 known compounds reported for the first time in the Meriania genus. The structures were elucidated by spectroscopic analyses including one- and two-dimensional NMR techniques and mass spectrometry. The bioactivities of the compounds were determined by measuring the DPPH radical scavenging activity and by carrying out antioxidant power assays (FRAP), etiolated wheat coleoptile assays and phytotoxicity assays on the standard target species Lycopersicum esculentum W. (tomato). Compounds 1 and 2 exhibited the best free radical scavenging activities, with FRS50 values of 2.0 and 1.9 µM, respectively.


Asunto(s)
Taninos Hidrolizables/química , Taninos Hidrolizables/farmacología , Melastomataceae/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular , Fitoquímicos/química , Fitoquímicos/farmacología , Relación Estructura-Actividad
17.
Phytochem Anal ; 30(1): 110-116, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30280444

RESUMEN

INTRODUCTION: Strigolactones (SLs) are the most representative germination stimulants for seeds of root parasitic plants, and they show activity even at concentrations below 10-10  M. The low amounts of stimulants produced by the host and their rapid degradability make it crucial to develop analytical methods with very low limits of quantification. OBJECTIVE: To develop a sensitive and validated analytical method for the simultaneous quantification of seven SLs [7-oxoorobanchyl acetate (1), solanacol (2), orobanchol (4), strigol (5), fabacyl acetate (6), orobanchyl acetate (7), and 5-deoxystrigol (8)]. METHODS: SLs were analysed using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS), with (±)-GR24 (3) employed as internal standard (IS). Validation was based on selectivity, linearity, precision of the peak areas (repeatability and intermediate precision), detection and quantification limits, and stability. RESULTS: A simple, rapid and reliable UHPLC-MS/MS method has been validated for the routine analysis of seven SLs and has been successfully applied to quantify them in exudates and extracts from tomato roots (Solanum lycopersicum). The limits of quantifications range from 0.05 µg/L for 5-deoxystrigol to 0.96 µg/L for solanacol. CONCLUSION: The method provides a useful tool for research in all the fields related to SLs, both for studies related to their function as hormones, and signalling molecules in the rhizosphere, without sample preparation required for extracts and root exudates in less than 11 minutes.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Lactonas/análisis , Extractos Vegetales/química , Raíces de Plantas/química , Solanum lycopersicum/química , Espectrometría de Masas en Tándem/métodos , Límite de Detección
18.
Colloids Surf B Biointerfaces ; 173: 85-93, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30273872

RESUMEN

Encapsulation techniques to generate core/shell systems provide a method that improves physicochemical properties, which are very important in biological applications. ß-carotene is a common carotenoid that has shown preventive effects in skin diseases and vitamin A deficiency but this compound has limited water solubility and bioavailability, which hinder its broad application. The use of polyrotaxane compounds formed from cyclodextrins has allowed supramolecular polymer micelles (SMPMs) to be synthesized to encapsulate ß-carotene. The polymeric compound Pluronic F127® was also used to create core/shell nanoparticles (NPs) that contain ß-carotene. Bioactive compound encapsulation was fully confirmed by nuclear magnetic resonance spectroscopy and by scanning and transmission electron microscopy. The method based on cyclodextrin and lecithin allow to release slowly when the systems were exposed to an aqueous medium by pH control, with an increase of 16 times of bioavailability comparing with free carotenoid. This allowed to potentiate the cytotoxic activity on a melanoma cell line by enhancing the water solubility to more than 28 mg/L, and present promising applications of SMPMs to provitamins.


Asunto(s)
Antioxidantes/química , Citotoxinas/química , Preparaciones de Acción Retardada , Composición de Medicamentos/métodos , Nanopartículas/química , beta Caroteno/química , Antioxidantes/farmacología , Disponibilidad Biológica , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ciclodextrinas/química , Citotoxinas/farmacología , Humanos , Concentración de Iones de Hidrógeno , Lecitinas/química , Melanocitos/efectos de los fármacos , Melanocitos/patología , Micelas , Nanopartículas/ultraestructura , Poloxámero/química , Rotaxanos/química , Solubilidad , beta Caroteno/farmacología
19.
J Agric Food Chem ; 65(25): 5161-5172, 2017 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-28605187

RESUMEN

Farmers of the Franca region in Brazil observed that Bidens sulphurea was able to eliminate the Panicum maximum weed, which infected coffee plantations, without affecting the crop. In an effort to determine if the inhibitory effects observed were due to the presence of phytotoxic compounds from leaves and roots, a biodirected isolation and spectroscopic characterization has been carried out. The leaf dichloromethane and root acetone extracts were the most active, and the former appeared to be more phytotoxic to the target species, including four weeds. A total of 26 compounds were isolated from leaves and roots, and four of them are described here for the first time. The major compounds in the leaf extract are the sesquiterpene lactones costunolide, reynosin, and santamarine, and these showed marked inhibition. Amaranthus viridis and Panicum maximum were the most sensitive species of the weeds tested. These three phytotoxic lactones were also evaluated on A. viridis and P. maximum under hydroponic conditions. A. viridis was the most affected species with the three lactones, and santamarine was the most phytotoxic compound on both. This is the first time that the phytotoxicity of sesquiterpene lactones has been evaluated on hydroponic culture. The work described here is a preliminary approach for the use of B. sulphurea for weed control in agriculture, both as a cover crop and by use of its components as natural herbicide leads.


Asunto(s)
Bidens/química , Herbicidas/toxicidad , Extractos Vegetales/toxicidad , Malezas/efectos de los fármacos , Amaranthus/efectos de los fármacos , Asteraceae/efectos de los fármacos , Brasil , Herbicidas/química , Herbicidas/aislamiento & purificación , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Raíces de Plantas/química , Control de Malezas
20.
Phytochemistry ; 141: 162-170, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28633108

RESUMEN

Isohexenylnaphthazarins are commonly found in the root periderm of several Boraginaceous plants and are known for their broad range of biological activities. The work described herein concerns the biological activity of compounds from the roots of Echium plantagineum L. and Echium gaditanum Boiss (Boraginaceae) collected from field sites in southern Spain and Australia. Bioactivity was assessed using etiolated wheat coleoptile bioassay and in vitro growth inhibitory activity in HeLa and IGROV-1 cells. The quantification of four isohexenylnaphthazarins (shikonin/alkannin, deoxyshikonin/deoxyalkannin, acetylshikonin/acetylalkannin and dimethylacrylshikonin/dimethylacrylalkannin) was performed by LC-MS/MS using juglone as internal standard. Correlation coefficient values for the activities and concentrations of these four analytes were in the linear range and were greater than 0.99. Acetylshikonin/acetylalkannin and dimethylacrylshikonin/dimethylacrylalkannin were present in the highest concentrations in extracts of both species. The results reveal that greatest overall inhibition was observed in both bioassays with E. gaditanum extracts. Strong correlations between time of collection, sampling location and bioactivity were identified.


Asunto(s)
Echium/química , Naftoquinonas/química , Raíces de Plantas/química , Australia , Línea Celular Tumoral , Supervivencia Celular , Echium/clasificación , Humanos , Naftoquinonas/aislamiento & purificación , Extractos Vegetales/química , España , Triticum/efectos de los fármacos
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