1,720,965 research outputs found
Chemical composition and biological properties of Synedrella nodiflora (L.) Gaertn: A comparative investigation of different extraction methods
No full textSynedrella nodiflora (L.) Gaertn. (Asteraceae), is a weed with ethnomedicinal uses. To extend scientific information on this species, we evaluated the effects of different extraction procedures (maceration, Soxhlet, sonication and homogenizer-assisted extraction (HAE)) using methanol as solvent, on the chemical composition and biological potential. The chemical profiles of the extracts were identified using a chromatographic (UHPLC-HRMS) technique. The antioxidant and enzyme inhibitory activities of the studied extracts were determined. The extract obtained by Soxhlet technique showed a higher level of total phenolic (TPC) and flavonoid content (TFC) and was a superior source of antioxidant compounds. The macerated extract was the most potent inhibitor of cholinesterases and α-glucosidase, whereas the highest activity against tyrosinase was observed in the order of sonication > Soxhlet > HAE > maceration. A modest activity was observed against α-amylase for all the extracts. Multivariate analysis showed that the bioactive compounds recovery and the biological activities of S. nodiflora were mostly dependent on the nature of the extraction technique used. In conclusion, S. nodiflora extracts showed good biological potential and data massed from this study could serve as a scientific baseline for further investigation in order to exploit its potential for designing novel bio-products with therapeutic applications
From small-scale studies to an encompassing view: Inhibiting inflammation and clinically relevant enzymes with various extracts of Primula vulgaris using in vitro and in silico techniques
Full text linkThe genus Primula holds great importance as a source of traditional remedies in various folk medicine systems. In the present study, we investigated the chemical composition and biological properties of different extracts (ethyl acetate, ethanol, ethanol/water, and water) of aerial parts and rhizomes of Primula vulgaris. To determine the chemical profile, the extracts were analyzed using ultrahigh performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) technique and flavonoids were a major group in this profile. The antioxidant capacity was demonstrated by in vitro chemical tests and in general the ethanol/water extract was found to be the most potent. Enzyme inhibition was studied against various enzymes and ethanol and ethanol/water extracts were more active than others. To assess the anti-inflammatory potential of the extracts at the molecular level, human dermal fibroblasts (HDF) were treated with lipopolysaccharide (LPS). In vitro experiments showed that the levels of nuclear factor kappa B (NFKB), receptor for advanced glycation endproducts (RAGE), activator protein-1 (AP-1), interleukin 6 (IL-6), interleukin 17 (IL-17) and tumor necrosis factor (TNF)-alpha were significantly reduced after treatment with the tested extracts. In addition, the extracts showed an inhibitory effect on the enzymes collagenase, elastase, and hyaluronidase, which are involved in the inflammatory process and destabilization of the extracellular matrix (ECM). P. vulgaris has been observed to modulate matrix metalloproteinase (MMP) synthesis by decreasing the concentration of cellular reactive oxygen species (ROS) during LPS-induced inflammation. This study also examined the molecular binding and dynamic behavior of various enzymes and proteins associated with skin and infections using ligands derived from the tested extracts. Simulations with AutoDock Vina V1.1.2 and GROMACS 2023.1 showed that isoquercetin in particular showed superior performance in interactions with hyaluronidase. These findings are important for the development of potential therapeutic strategies for skin health and infection control. In summary, P. vulgaris can be considered as an important source of natural bioactive compounds for the development of effective health-promoting applications in nutraceuticals, pharmaceuticals, and cosmetics
Uhplc-ms characterization and biological insights of different solvent extracts of two achillea species (A. aleppica and a. santolinoides) from Turkey
Full text linkIn the current study, Achillea santolinoides and Achillea aleppica aeral parts and root were extracted with ethyl acetate, methanol, and water. Detailed phytochemical profiles were obtained using UHPLC-MS, yielding the identification of hydroxybenzoic and hydroxycinnamic acids, phenolic acid glycosides and sugar esters, acylquinic acids, O-glycosyl flavones and flavonols, and flavonoid aglycons, among others. The antioxidant properties and enzyme inhibitory activities of the extracts were assayed with in vitro tests. The phenolic content of the water extracts was significantly higher as compared to the ethyl acetate and methanol ones. A. aleppica aerial parts methanol extract possessed highest flavonoid content (49.18 mg rutin equivalent/g). Antioxidant properties assess-ment revealed that the methanol extract of A. santolinoides roots actively scavenged DPPH (54.11 mg TE/g) and ABTS radicals (112.53 mg TE/g) and possessed highest reducing potential (183.55 and 129.92 mg TE/g, for CUPRAC and FRAP, respectively). The ethyl acetate extracts of aerial parts and roots of both species showed highest inhibition against BuCHE (6.07–6.76 mg GALAE/g). The ethyl acetate extract of A. santolinoides aerial part showed highest inhibition against tyrosinase (73.00 mg KAE/g). These results showed that the tested Achillea species might represent novel phytotherapeu-tic avenues for the management of Alzheimer’s disease and epidermal hyperpigmentation condi-tions, which are both associated with oxidative stress. This paper could shed light into future potential industrial applications using the tested Achillea species
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
Chemical profiling and pharmaco-toxicological activity of Origanum sipyleum extracts: Exploring for novel sources for potential therapeutic agents
No full textThe phytochemical, antiradical, and enzyme inhibition profile of three solvent extracts (ethyl acetate, methanol, water) of Origanum sipyleum were assessed. We also performed a pharmacological study in order to explore protective effects induced by extracts in inflamed colon. LC-MS analysis revealed that the extracts contained different classes of phenolics. The aqueous extract showed the highest antioxidant and acetylcholinesterase (AChE) inhibitory effects. Total phenol and flavonoid contents were highest in aqueous and ethyl acetate extract, respectively. All extracts were effective in reducing colon pro-oxidant and pro-inflammatory biomarkers. The extracts revealed also able to inhibit fungal and bacterial species involved in ulcerative colitis, including Candida albicans, Candida tropicalis, Staphylococcus aureus, and Staphylococcus thyphimurium. Finally, we also showed the antiproliferative effects exerted by the EA extracts on human colon cancer HCT116 cell line. Concluding, our results indicated that O. sipyleum extracts displayed promising therapeutic properties which warrants further validation. Practical applications The present phytochemical and biological studies, including antioxidant, anti-inflammatory, and antimicrobic assessments, showed significant protective effects exerted by O. sipyleum extracts in an experimental model of ulcerative colitis. The results are intriguing and suggest potential applications O. sipyleum extracts as sources of natural agents for the management of clinical symptoms related to ulcerative colitis, characterized by increased burden of oxidative stress and microbiome dysbiosis
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
Exploring the chemical profiles and biological values of two spondias species (S. Dulcis and S. Mombin): Valuable sources of bioactive natural products
Full text linkSpondias species have been used in traditional medicine for different human ailments. In this study, the effect of different solvents (ethyl acetate, methanol, and water) and extraction methods (infusion, maceration, and Soxhlet extraction) on the enzyme inhibitory activity against acetylcholinesterase, butyrylcholinesterase, tyrosinase, α-amylase, α-glucosidase, and antioxidant properties of S. mombin and S. dulcis leaves and stem bark were evaluated. Ultra-high-performance liquid chromatography–high resolution mass spectrometry (UHPLC-HRMS) yield in the identification and/or annotation of 98 compounds showing that the main secondary metabolites of the plant are gallic and ellagic acids and their derivatives, ellagitannins, hydroxybenzoic, hydroxycinnamic, acylquinic acids and flavonols, flavanones, and flavanonols. The leaves infusion of both Spondias species showed highest inhibition against acetylcholinesterase (AChE) (10.10 and 10.45 mg galantamine equivalent (GALAE)/g, for S. dulcis and S. mombin, respectively). The ethyl acetate extracts of the stem bark of S. mombin and S. dulcis actively inhibited α-glucosidase. Methanolic extracts of the leaves and stem bark exhibited highest tyrosinase inhibitory action. Antioxidant activity and higher levels of phenolics were observed for the methanolic extracts of Spondias. The results suggested that the Spondias species could be considered as natural phyto-therapeutic agents in medicinal and cosmeceutical applications
Detailed Chemical Characterization and Biological Propensities of Malabaila lasiocarpa Extracts: An Endemic Plant to Turkey
No full textThis study focused on the biological evaluation and chemical characterization of Malabaila lasiocarpa Boiss. (M. lasiocarpa) (Family: Apiaceae). The phytochemical profile, antioxidant, enzyme inhibitory of the methanolic, aqueous, dichloromethane, hexane extracts were investigated. Based on UHPLC-HRMS analyses, a total of 101 peaks were annotated or identified for the first time in M. lasiocarpa extracts. They include hydroxybenzoic, hydroxycinnamic, acylquinic acids and their glycosides, C- and O-glycosyl and O-diglycosyl flavonoids. In addition, 10 simple mono- and disubstituted coumarins together with 10 furanocoumarins were tentatively annotated. The methanolic extract possessing the highest phenolic (24.36±0.60 mg gallic acid equivalent/g extract) and flavonoid (69.15±0.37 mg rutin equivalent/g extract) content also exhibited the strongest radical scavenging potential against 2,2-diphenyl-1 picrylhydrazyl (21.73±0.42 mg Trolox equivalent/g extract, respectively), and highest reducing capacity (57.81±0.97 and 28.00±0.40 mg Trolox equivalent/g extract, for cupric reducing antioxidant capacity and ferric reducing antioxidant power, respectively). The dichloromethane extract substantially depressed the tyrosinase (73.92±5.37 mg kojic acid equivalent/g extract), α-amylase (0.63±0.01 mmol acarbose equivalent/g extract) and α-glucosidase (0.69±0.02 mmol acarbose equivalent/g extract) enzymes. This study has produced critical scientific data on M. lasiocarpa which are potential contenders for the development of novel phyto-pharmaceuticals
- …
