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2014, Botanical Studies
Aquatic Toxicology
Microcosm evaluation of the effects of an eight pharmaceutical mixture to the aquatic macrophytes Lemna gibba and Myriophyllum sibiricum2004 •
2014 •
Leucas aspera (Lamiaceae), an aromatic herbaceous plant, is well known for many medicinal properties and a number of bioactive compounds against animal cells have been isolated. However, phytotoxic substances from L. aspera have not yet been documented in the literature. Therefore, current research was conducted to explore the phytotoxic properties and substances in L. aspera. Aqueous methanol extracts of L. aspera inhibited the germination and growth of garden cress (Lepidum sativum) and barnyard grass (Echinochloa crus-galli), and the inhibitory activities were concentration dependent. These results suggest that the plant may have phytotoxic substances. The extracts were then purified by several chromatographic runs. The final purification was achieved by reversed-phase HPLC to give an equilibrium (or inseparable) 3:2 mixture of two labdane type diterpenes (compound 1 and 2). These compounds were characterized as (rel 5S,6R,8R,9R,10S,13S,15S,16R)-6-acetoxy-9,13;15,16-diepoxy-15-hydroxy-16-methoxylabdane (1) and (rel 5S,6R,8R,9R,10S,13S,15R,16R)-6-acetoxy-9,13;15,16-diepoxy-15-hydroxy-16-methoxylabdane (2) by spectroscopic analyses. A mixture of the two compounds inhibits the germination and seedling growth of garden cress and barnyard grass at concentrations greater than 30 and 3 μM, respectively. The concentration required for 50% growth inhibition (I50) of the test species ranges from 31 to 80 μM, which suggests that the mixture of these compounds, are responsible for the phytotoxic activity of L. aspera plant extract. Copyright © 2014 Published by Elsevier GmbH
Archives of Natural and Medicinal Chemistry
An Investigation of Phytoconstituents, Cytotoxicity and Proximate Analysis of Some Medicinal Plants in Kashere, Gombe State - Nigeria2018 •
Excessive use of herbicide in the crop field threatens the environment by destroying flora and fauna. Allelopathic substances could be act as substitutes of chemical herbicides to suppress the target plants. Leucas aspera (Willd.) Linn., a herbaceous plant has already provided tangible evidence of its potential with remedies for different sorts of medical problems, but still now, not a single work is reported related to its allelopathic activity. Hence, to explore the allelopathy of L. aspera, the aqueous methanol extracts of this plant at four different concentrations (3, 10, 30 and 100 mg dry weight equivalent extract mL–1) were tested against seven test plant species, namely cress (Lepidum sativum L.), alfalfa (Medicago sativa L.), lettuce (Lactuca sativa L.), Italian ryegrass (Lolium multiflorum Lam.), barnyard grass (Echinochloa crusgalli L.), jungle rice (Echinochloa colonum L. Link) and timothy (Phleum pratense L.). The aqueous methanol extract of L. aspera significantly inhibited the seedlings growth of all the test plant species at different inhibition levels. The root growth was more sensitive than the shoot growth to the plant extract and the inhibitory activity was concentration dependent. Comparing the extract concentrations required for 50% inhibition, the seedlings growth of timothy was most sensitive to the extract, whereas jungle rice was less sensitive. These results indicated that L. aspera may contain growth inhibitory substances and possess allelopathic activity. Therefore, L. aspera could be used as a potential candidate for isolation and identification of allelochemicals, which can lead to the development of ecologically acceptable bio-herbicides used for sustainable agriculture.© 2012 idosi Publishing Group
Aquatic weeds are higher plants found in the aquatic ecosystem and in anaerobic rice fields, where they have no economic benefits. The continuance of aquatic weeds is more widespread than terrestrial weeds because in aquatic ecosystems there is very little fluctuation in the environmental conditions compared with terrestrial ecosystems. Scientists have been working to address the harmful allelopathic effects of aquatic weeds on the aquatic ecosystem, but limited information is available on the allelopathic influence of aquatic weeds on agro-ecosystems through the release of phytotoxic compounds. Phytotoxic chemicals released by different aquatic weeds into irrigation water and/or directly into rice ecosystems might have a significant inhibitory influence on germination, growth and yield field crops, soil properties and nutrients availability, population and community structure, and weed invasion. However, aquatic weeds might also be used as a potential organic alternative to chemical weed-control, due to the higher susceptibility of terrestrial weeds to the phototoxic chemicals released by aquatic weeds. Natural alternatives to chemical weed control are need of time and are crucial for a sustainable weed control. Chemical weed control is challenged, due to recent increases in herbicides resistance from weeds and to the harmful side-effects of herbicides on the environment. This review is focused on the influence of aquatic weeds on agro-ecosystems, with examples of common weeds in aquatic ecosystems and invasive aquatic weeds found in anaerobic rice. RESUMO-As plantas daninhas aquáticas são plantas superiores encontradas no ecossistema aquático e em plantações de arroz anaeróbio, onde não têm vantagens econômicas. A continuidade das plantas daninhas aquáticas é mais difundida do que a das plantas daninhas terrestres, pois nos ecossistemas aquáticos há flutuação muito baixa nas condições ambientais, em comparação com ecossistemas terrestres. Os cientistas têm trabalhado para abordar os efeitos nocivos alelopáticos dessas plantas nos ecossistemas aquáticos, mas há informações limitadas à disposição sobre a influência alelopática das plantas daninhas no ecossistema agrícola através da liberação de compostos fitotóxicos. Os compostos químicos fitotóxicos liberados por diferentes plantas daninhas aquáticas na água de irrigação e/ou diretamente no ecossistema do arroz podem ter significativa influência inibitória na germinação, no crescimento e rendimento das culturas, nas propriedades do solo e na disponibilidade de nutrientes, na estrutura da população e da comunidade e na invasão de plantas daninhas. No entanto, as plantas daninhas aquáticas podem ser usadas como uma potencial alternativa orgânica ao controle químico das
Journal of agricultural and food chemistry
Phytotoxicity of cardoon (Cynara cardunculus) allelochemicals on standard target species and weedsCardoon (Cynara cardunculus L.) is a native plant to the Iberian Peninsula and the European Atlantic coast and invasive in American environments. Different solvents were used to perform cardoon extracts that were tested in phytotoxic bioassays. The ethyl acetate extract had the highest inhibitory activity so this was tested on the germination and growth of standard target species (lettuce, watercress, tomato, and onion) and weeds (barnyardgrass and brachiaria). The ethyl acetate extract was very active on root growth in both standard target species and weeds and it was therefore fractionated by chromatography. The spectroscopic data showed that the major compounds were sesquiterpene lactones. Aguerin B, grosheimin, and cynaropicrin were very active on etiolated wheat coleoptile, standard target species, and weed growth. The presence of these compounds explains the bioactivity of the ethyl acetate extract. The strong phytotoxicity of these compounds on important weeds shows the poten...
Medicinal and Aromatic Plants
Toxicity: Its Assessment and Remediation in Important Medicinal Plants2021 •
2020 •
Scientific Reports
Impact of land configuration and organic nutrient management on productivity, quality and soil properties under baby corn in Eastern Himalayas2020 •
Science of The Total Environment
Occurrence of legacy and emerging organic pollutants in whitemouth croakers from Southeastern Brazil2019 •
Computer Graphics Forum
Hierarchical Vortex Regions in Swirling Flow2009 •
Environmental Modeling & Assessment
Competitive Markets for Pollution Permits: Impact on Factor Income and International Equilibrium2009 •
Anuario De Historia Del Derecho Espanol
Los primeros ataques legislativos limitadores de la gran propiedad privada de la tierra generada por la revolución liberal: los proyectos de reforma agraria de principios de siglo XX de Canalejas y de Dato-Lizárraga1999 •
2005 IEEE/RSJ International Conference on Intelligent Robots and Systems
Biologically-inspired self-deployable heterogeneous mobile sensor networks2005 •
Proceedings of the National Academy of Sciences
Cholesterol uptake disruption, in association with chemotherapy, is a promising combined metabolic therapy for pancreatic adenocarcinoma2015 •
Research, Society and Development
Benefits in using early intervention in children with autista spectrum disorder (ASD): an integrative review2020 •
2020 •
Forest Research Papers
The influence of seedling density in containers on morphological characteristics of European beech2015 •
2005 •
The Journal of Infection in Developing Countries
Preparing dental schools to refunction safely during the COVID-19 pandemic: an infection prevention and control perspective2021 •
Earthquake Spectra
Induced earthquake damage assessment methodology for potential hydraulic fracturing sites: Application to Manaus, Brazil2020 •
2019 •
Monthly Notices of the Royal Astronomical Society: Letters
Formation of precessing jets by tilted black hole discs in 3D general relativistic MHD simulations2017 •
Папков, В. Е. Гендер как психогигиенический фактор риска второго демографического перехода / В. Е. Папков // Вестник гигиены и эпидемиологии. – 2023. – Т. 27, № 3. – С. 166-172. .
ГЕНДЕР КАК ПСИХОГИГИЕНИЧЕСКИИ ФАКТОР РИСКА ВТОРОГО ДЕМОГРАФИЧЕСКОГО ПЕРЕХОДА2023 •
Cerebral Cortex
Spatiotemporal target selection for intracranial neural decoding of abstract and concrete semantics2022 •
Instituciones de Educación Superior y emprendimiento: estudios de caso y estrategias de consolidación
Proyecto STEM como modelo de emprendimiento: El caso del cultivo de cacao bajo un sistema agroforestal en la Huasteca Sur