Search results for "plants"
showing 10 items of 1914 documents
Junceosides A-C, new triterpene saponins from Arenaria juncea.
2002
Three novel triterpenoid saponins, junceosides A (1), B (2), and C (3), together with two known saponins have been isolated from the roots of Arenaria juncea. Their structures were elucidated using a combination of homo- and heteronuclear 2D NMR techniques (COSY, TOCSY, NOESY, HSQC, and HMBC) and by FABMS. The new compounds were characterized as 3-O-alpha-L-arabinopyranosyl-(1-->2)-[beta-D-galactopyranosyl-(1-->3)]-beta-D-glucuronopyranosylgypsogenin-28-O-beta-D-glucopyranosyl(1-->3)-[beta-D-xylopyranosyl-(1-->4)]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranoside (1), 3-O-alpha-L-arabinopyranosyl-(1-->2)-[beta-D-galactopyranosyl-(1-->3)]-beta-D-glucuronopyranosylgypsogenin-28-O-beta-D-x…
Hypolaetin-8-O-Glucoside, An Anti-inflammatory Flavonoid from Sideritis mugronensis.
1985
Cytotoxicity and antileishmanial activity of Annona muricata pericarp
2000
Abstract Hexane, ethyl acetate and methanol extracts of Annona muricata pericarp were tested in vitro against Leishmania braziliensis and L. panamensis promastigotes, and against cell line U-937. The ethyl acetate extract was more active than the other extracts and even of Glucantime® used as reference substance. Its fractionation led to the isolation of three acetogenins — annonacin, annonacin A and annomuricin A.
Cytotoxic Spirostane-Type Saponins from the Roots of Chlorophytum borivilianum
2009
Four new spirostane-type saponins named borivilianosides E-H (1-4) were isolated from an ethanol extract of the roots of Chlorophytum borivilianum together with two known steroid saponins (5 and 6). The structures of 1-4 were elucidated using mainly 2D NMR spectroscopic techniques and mass spectrometry. The cytotoxicity of borivilianosides F (2), G (3), and H (4) and three known compounds was evaluated using two human colon cancer cell lines (HT-29 and HCT 116).
Mitosis Inhibitors and Medicinal Plants: Neurotoxicity and Neuroprotection
2021
Cancer is one of the devastating diseases worldwide, causing desperate outcomes and high mortality rates. Despite undeniable improvements in cancer treatment, many patients with malignancies still suffer from adverse drug reactions, among which peripheral neurotoxicity holds great importance. Peripheral neuropathy as a representation of peripheral neurotoxicity is a usual complication of chemotherapy, reducing the life quality of individuals since it can adversely induce sensory and motor dysfunctions influencing patients’ life. Mitosis inhibitors are substantially administered drugs during chemotherapy. However, these drugs may induce the occurrence of chemotherapy-induced peripheral neuro…
Schools That ‘Open Doors’ to Prevent Child Abuse in Confinement by COVID-19
2020
Background: Due to the expected increase in child abuse during the period of COVID-19 confinement, it is essential that social researchers and other professionals work together very quickly to provide alternatives that protect children. To respond to this extremely urgent demand, evidence-based actions are presented that are being carried out in nine schools in the autonomous communities of Valencia and Murcia, Spain, during the confinement with the goal of “opening doors” to foster supportive relationships and a safe environment to prevent child abuse. Methods: The research was conducted through the inclusion of teachers who are implementing these actions in dialogue with the researchers t…
Sustainable Development and Energy Policy: Actual CO2 Emissions in the European Union in the Years 1997–2017, Considering Trade with China and the USA
2020
One of the ways of implementing the concept of sustainable development by the European Union is their energy policy. Among the three main objectives in its energy policy is a reduction in greenhouse gases (mainly CO2) emissions to at least 20% below 1990 levels by 2020. This study aims to assess the impact of international trade on actual CO2 emission in the EU, China and the USA for the period 1997–2017. For this aim, the Actual-Open CO2 emissions were calculated, taking into account the transfer of CO2 in exported products and services from China and the USA to the EU and vice versa. It is concluded that the actual CO2 emissions in China, the USA, and the EU differed from the traditionall…
Intellectual Structure of the Belt and Road Initiative Research: A Scientometric Analysis and Suggestions for a Future Research Agenda
2020
China’s Belt and Road Initiative (BRI) has attracted increasing attention worldwide since its inception in 2013. Although the research is fast increasing in terms of publications, there is a lack of knowledge about the intellectual structure, research trends, and appropriate theories underpinning. Using bibliometric data from 1583 articles from 2013 to 2019 in the Web of Science and Scopus databases, we used bibliometric techniques and scientometric analyses to identify and analyze the intellectual structure, hotspots, and emerging trends in this field. We identified 18 clusters that we categorized into three groups for thematic discussion. Research gaps and future research directions were …
Organization of the pigment molecules in the chlorophyll a/c light-harvesting complex of Pleurochloris meiringensis (xanthophyceae). Characterization…
1997
Abstract By the aid of circular dichroism (CD), absorbance and fluorescence spectroscopy, we studied the molecular organization of the pigment molecules in cells, isolated chloroplasts and the chlorophyll a / c light-harvesting complex (LHC) associated with photosystem II of the chlorphyll c -containing alga, Pleurochloris meiringensis . In cells and chloroplasts, similarly to higher plant chloroplasts, a (+) 693 nm CD band accompanied by a tail outside the absorbance indicated a long-range chiral organization of the chlorophyll molecules. The LHCII of these algae exhibited an intense negative CD band at 679 nm. However, in contrast to the chlorophyll a / b LHCII of higher plants, where the…
Early Steps in the Assembly of Light-harvesting Chlorophyll a/b Complex
2004
The light-harvesting chlorophyll a/b complex (LHCIIb) spontaneously assembles from its pigment and protein components in detergent solution. The formation of functional LHCIIb can be detected in time-resolved experiments by monitoring the establishment of excitation energy transfer from protein-bound chlorophyll b to chlorophyll a. To detect the possible initial steps of chlorophyll binding that may not yet give rise to chlorophyll b-to-a energy transfer, we have monitored LHCIIb assembly by measuring excitation energy transfer from a fluorescent dye, covalently bound to the protein, to the chlorophylls. In order to exclude interference of the dye with protein folding or pigment binding, th…