1,721,009 research outputs found
Natural products in cancer prevention and therapy, trends in methods and modelling, 3rd edition, Phytochemical Society of Europe (PSE) symposium (Naples, Italy, 4–7 September 2018)
No full textCorn poppy, Papaver rhoeas L.: a critical review of its botany, phytochemistry and pharmacology
No full textPapaver rhoeas L. (Papaveraceae), commonly known as corn poppy, is a cosmopolitan weed and edible plant capable of possessing biological properties, thus positive correlating with human health. The plant is also known as field poppy, flanders poppy or shirley poppy. It can be consumed raw or cooked, and has been traditionally used to treat nervousness, insomnia, digestive and respiratory disorders, baldness, eye infections, as well as measles treatment. This paper is aimed to contribute to the knowledge of corn poppy by providing a critical review of the botanic characteristics, the traditional uses, the plant chemistry and pharmacology
Metabolomics of the alimurgic plants Taraxacum officinale, Papaver rhoeas and Urtica dioica by combined NMR and GC–MS analysis
No full textIntroduction: The phytoalimurgic plants, common dandelion (Taraxacum officinale),
corn poppy (Papaver rhoeas) and stinging nettle (Urtica dioica) are a source of
nutraceuticals.
Objectives: To apply a combined metabolomic fingerprinting approach by nuclear
magnetic resonance (NMR) and gas chromatography–mass spectrometry (GC–MS)
to common dandelion, corn poppy and stinging nettles to obtain simultaneous
identification and quantitation of the major classes of organic compounds.
Methodology: The whole plants collected in the Cilento National Park were dried
and then extracted to obtain non‐polar and polar organic extracts. GC–MS was used
for non‐polar extracts while 1
H‐NMR spectroscopy was used for polar extracts. In
both cases, simultaneous identification and quantification of the bioactive
metabolites was obtained.
Results: Non‐polar organic extracts of all plants were mainly composed of palmitic,
stearic and oleic acids. The two pentacyclic triterpenols α‐ and β‐amyrin were
detected in nettle extract. The analysis of polar organic extracts allowed to detect
and quantify organic acids and sugars as main metabolites along with amino acids,
caffeoyl derivatives, flavonoids, and nucleotides. In particular, corn poppy leaves
contained a huge amount of glyceric acid (55.7% of the total extract). Stinging nettles,
instead, exhibited a large amount of choline (19.5%).
Conclusion: Metabolomic approach coupling GC–MS with NMR spectroscopy
allowed to provide a detailed metabolite profile of three alimurgic plants, common
dandelion, corn poppy and stinging nettle, from both a qualitative and quantitative
point of vie
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Computational prediction of chiroptical properties in structure elucidation of natural products
No full textThis review covers the current status of the quantum mechanical prediction of chiroptical properties, such as electronic CD and optical rotation, as needed for stereochemical assignments in new natural products. The reliability of the prediction of chiroptical properties is steadily increasing, with a parallel decrease in the required computational resources. Now, quantum mechanical calculations for a medium-sized natural product can be reliably performed by natural product chemists on a mainstream PC. This review is aimed to guide natural product chemists through the numerous steps involved in such calculations. Through a concise, but comprehensive, discussion of the current computational practice, enriched by a few illustrative examples, this review provides readers with the theoretical background and practical knowledge needed to select the most appropriate parameters for performing the calculations, to anticipate possible problems, and to critically evaluate the reliability of their computational results. Common reasons for mistakes are also discussed; in particular, the importance of the correct evaluation of conformational ensembles of flexible molecules (an aspect often overlooked in current research) is stressed
Common dandelion: a review of its botanical, phytochemical and pharmacological profiles
No full textPhytoalimurgy is a term that derives from
Greek and Latin by combination of the words φυτόν,
which meaning plant, and alimenta urgentia, indicating
foods available in case of urgency and necessity.
Nowadays, the lack of products from agriculture is
fortunately no longer a problem, however, the interest
in using the phytoalimurgic plants has increased in
the last years due to their rediscovery for use of food
ingredients for human health. Among these, common
dandelion, Taraxacum officinale, is used since ancient
times because of its curative properties. The aim of
this review is the contribution to the knowledge of
this worldwide-spread phytoalimurgic plant with its
botanical, phytochemical and pharmacological
description. In vitro and in vivo scientific investigations
have confirmed its pharmacological potential by
showing antioxidant, antibacterial, anti-inflammatory,
antiviral, cytotoxic, diuretic and
hepatoprotective properties. Responsible of these
activities are bioactive metabolites belonging to
different classes, including sesquiterpenoids, caffeoylquinic
acids and flavonoids. This allows to
include dandelion among the medicinal plants of
commercial interest for nutraceutical and phytopharmaceutical
industries
Investigation of the spirolide profile of adriatic Alexandrium ostenfeldii by liquid chromatography tandem mass spectrometry.
No full text- …
