1,720,971 research outputs found
Wild aromatic plants bioactivity: a function of their (poly)phenol seasonality? A case study from Mediterranean area
No full textWild medicinal and aromatic plants are in the market as herbal raw or processed and packaged materials, playing, even today, a strategic role in the production of plant-based products. Indeed, their content in active ingredients, mainly specialized secondary metabolites, is not constant; it undergoes significant seasonal variations, as abiotic stress heavily affects secondary metabolism network. The present review deals with the seasonality influence on the polyphenolic composition on antioxidant and anti-inflammatory properties of medicinal and aromatic plants. To this aim, firstly the factors influencing the content of active ingredients in a plant drug will be discussed, and, in particular, the increased occurrence of phenols as a response to abiotic stress. In the last part of the review a brief reference will be made to four meaningful case studies, which involve wild medicinal aromatic herbs, native to the Mediterranean area: Calamintha nepeta L. Savi, Foeniculum vulgare Mill., Ruta graveolens L. and Thymus longicaulis C. Presl. These species, grown in the same geographical area and collected at the same harvesting time, showed a great variability in phenol constituents throughout the year. The comparison among data acquired clearly evidences that the seasonal variation in polyphenols’ occurrence and amount leads to a more/less pronounced antioxidant and anti-inflammatory activity of the hydroalcoholic extract therefrom. It is worth of note that the presence of the same metabolite, but in different phytochemical complexes, could result in different biological activities
Cancer Initiation, Progression and Resistance: Are Phytocannabinoids from Cannabis sativa L. Promising Compounds?
No full textCannabis sativa L. is a source of over 150 active compounds known as phytocannabinoids that are receiving renewed interest due to their diverse pharmacologic activities. Indeed, phytocannabinoids mimic the endogenous bioactive endocannabinoids effects through activation of CB1 and CB2 receptors widely described in the central nervous system and peripheral tissues. All phytocannabinoids have been studied for their protective actions towards different biological mechanisms, including inflammation, immune response, oxidative stress that, altogether, result in an inhibitory activity against the carcinogenesis. The role of the endocannabinoid system is not yet completely clear in cancer, but several studies indicate that cannabinoid receptors and endogenous ligands are overexpressed in different tumor tissues. Recently, in vitro and in vivo evidence support the effectiveness of phytocannabinoids against various cancer types, in terms of proliferation, metastasis, and angiogenesis, actions partially due to their ability to regulate signaling pathways critical for cell growth and survival. The aim of this review was to report the current knowledge about the action of phytocannabinoids from Cannabis sativa L. against cancer initiation and progression with a specific regard to brain, breast, colorectal, and lung cancer as well as their possible use in the therapies. We will also report the known molecular mechanisms responsible for such positive effects. Finally, we will describe the actual therapeutic options for Cannabis sativa L. and the ongoing clinical trials
Cannabis Bioactive Compound-Based Formulations: New Perspectives for the Management of Orofacial Pain
No full textThe management of orofacial pain to alleviate the quality of life of affected patients is becoming increasingly challenging for scientific research and healthcare professionals. From this perspective, in addition to conventional therapies, new alternatives are being sought, increasingly looking at the use of both natural and synthetic products. Cannabis sativa L. represents an interesting source of bioactive compounds, including non-psychoactive cannabinoids, flavonoids, and terpenes, many of which are effective in improving pain intensity. Here, we aim to analyze the possible mechanisms of action of the bioactive natural and synthetic hemp-derived compounds responsible for the modulatory effects on pain-related pathways. The ability of these compounds to act on multiple mechanisms through a synergistic effect, reducing both the release of inflammatory mediators and regulating the response of the endocannabinoid system, makes them interesting agents for alternative formulations to be used in orofacial pain
Can agronomic practices and cold-pressing extraction parameters affect phenols and polyphenols content in hempseed oils?
No full textAbstract View references (28)
Hemp seed oil is an extraordinary dietary source of polyunsaturated fatty acids (PUFAs), to huge health benefits are related. PUFAs abundance could indeed contribute the oil turning rancid and deteriorating through oxidation. Thus, antioxidant compounds, characteristic of hemp seed matrix, should be more favorably extract to hopefully safeguard the oil stability. Moreover, antioxidants ability to counteract the onset of oxidative stress-related diseases could be employed to further enhance hemp seed oil functional value. In this context, phenols and polyphenols, which are poorly explored in hempseed oil so far, are thoroughly investigated by untargeted UHPLC-HRMS and MS/MS techniques in seed oils from Cannabis sativa L. cv USO31. Data recorded highlighted that hemp seed oil could contain, as minor constituents, saccharides, phenol compounds (some of them never described before - e.g. tyrosol hexoside, caffeoyl tartaric acid isomers), as well as flavonoids, of which glycosides of flavonols quercetin, kaempferol and isorhamnetin were the most representative. Glucuronide derivatives were also present. Multivariate principal-component analysis (PCA) highlighted that agronomic practices (e.g. plant density/m2, use of fertilizers) and cold-pressing extraction parameters (e.g. temperature, nozzle size) massively affected the relative content of each compounds’ class. Hemp seeds from soils, which did not undergo pre-seeding fertilization, and with 60 plant/m2crop density, ensured the highest production of phenols and polyphenols, whereas their abundance could be compromised when the plant density was halved. © 2019 Elsevier B.V
A nutraceutical extract from Inula viscosa leaves: UHPLC-HR-MS/MS based polyphenol profile, and antioxidant and cytotoxic activities
No full textNowadays, advanced extraction techniques and highly sensitive metabolic profiling methods are effectively employed to get new information on plant chemical constituents. Among them wild medicinal plants or their parts, with large and ancient use in folk medicine, are investigated for their potential functional use and cultivation. In this context, Inula viscosa leaves engaged our attention. A simple experimental design, based on Soxhlet extraction and chromatographic fractionation, allowed us to obtain the investigated polyphenol fraction (IvE). UHPLC-HRMS analyses revealed shikimoyl depsides of caffeic acid and unusual dihydrobenzofuran lignans as main secondary metabolites. These compounds, together with cinchonain-type phenols, and hydroxycinnamoyl flavonol glycosides, are reported for the first time in inula. Overall, forty-three secondary metabolites were identified. The extract exerted a remarkable antiradical activity towards DPPH• and ABTS+•. Furthermore, it was able to inhibit cell viability and mitochondrial redox activity of neuroblastoma, hepatoblastoma and colon carcinoma cells, whereas it did not affect cell density of HaCaT cells immortalized human keratinocytes. As detected by the oxidant-sensing probe 2′,7′-dichlorodihydrofluorescein diacetate, the inhibitory responses seemed to be related to IvE-induced increase of intracellular reactive oxygen species (ROS). The obtained results highlighted that inula leaves, nowadays even undervalued and unexplored, could be considered a renewable source of nutraceutical compounds
New SiO2/Caffeic Acid Hybrid Materials: Synthesis, Spectroscopic Characterization, and Bioactivity
Full text linkThe sol–gel route represents a valuable technique to obtain functional materials, in which organic and inorganic members are closely connected. Herein, four hybrid materials, containing caffeic acid entrapped in a silica matrix at 5, 10, 15, and 20 wt.%, were synthesized and characterized through Fourier-Transform Infrared (FT-IR) and Ultraviolet-Visible (UV–Vis) spectroscopy. FT-IR analysis was also performed to evaluate the ability to induce the hydroxyapatite nucleation. Despite some structural changes occurring on the phenol molecular skeleton, hybrid materials showed scavenging properties vs. 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2′-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid) radical cation (ABTS•+), which was dependent on the tested dose and on the caffeic acid wt.%. The SiO2/caffeic acid materials are proposed as valuable antibacterial agents against Escherichia coli and Enterococcus faecalis
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
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