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1.
Int J Mol Sci ; 24(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37511606

RESUMO

Willow bark (Salix spp., Salicaceae) is a traditional analgesic and antirheumatic herbal medicine. The aim of this study was to evaluate and compare the phytochemical and antioxidant profiles of leaf and bark extracts of six species of the genus Salix obtained by ultrasound-assisted extraction (UAE) and to examine the inhibitory potential of target bioactive compounds against two inflammatory mediators, tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6), through in silico molecular docking. The total phenolic and flavonoid content of the extracts was estimated using spectrophotometric methods and the antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and hydroxyl radical (•OH) scavenging assays. Chemical profiling of extracts was carried out using high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD). Principal component analysis (PCA) was performed to differentiate the sample extracts based on their phytochemical profiles and amounts of target bioactive compounds. Chemical composition varied among the analyzed willow species and also among the plant organs of the same species. The major bioactive compounds of the extracts were salicin, chlorogenic acid, rutin and epicatechin. The extracts exhibited significant DPPH● and ●OH scavenging activities. Results of molecular docking revealed that chlorogenic acid had the highest binding affinity toward TNF-α and IL-6. UAE extracts represent valuable sources of antioxidant and anti-inflammatory compounds.


Assuntos
Antioxidantes , Salix , Antioxidantes/química , Salix/química , Simulação de Acoplamento Molecular , Citocinas , Ácido Clorogênico/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6 , Ultrassom , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia
2.
Oecologia ; 202(2): 275-285, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37266587

RESUMO

Bryophytes play important role in forest ecosystem functioning and their distribution and diversity are driven by numerous environmental factors. The aim of the present study was to bring new insights in deeper understanding of terrestrial bryophytes diversity in temperate forests, as well as to determine the environmental factors which have predominant influence on ground-floor bryophytes. The survey was conducted in Fruska Gora Mountain (Serbia) across seven forest sites where ground-bryophytes were sampled. Soil moisture, temperature, and pH were measured as soil characteristics, while herbaceous cover, litter cover, stream distance, number of trees and shrubs were used as characteristics of stand structure. Species richness, Shannon diversity index, and evenness index were used as diversity measures. Generalised linear model and canonical correspondence analysis (CCA) were used to test the influence of environmental variables on bryophyte diversity. Litter cover was the most important explanatory variable, followed by soil moisture, stream distance and tree number, respectively. Overall, the stand structure was found to have a greater impact on ground-floor bryophyte diversity compared to soil characteristics. Identification of the most significant ecological factors affecting the diversity and distribution of bryophytes in forest ecosystems is of great importance in forest ecology with the aim of defining adequate management methods to preserve the biodiversity of forests, with particular emphasis on endangered and rare bryophyte species.


Assuntos
Briófitas , Ecossistema , Florestas , Biodiversidade , Árvores , Solo
3.
Plant Foods Hum Nutr ; 76(2): 240-247, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34106402

RESUMO

The possibility to prevent nutrition-related diseases that include scavenge of free radicals and to block chain reactions is very important and significant for human well-being. The aim of this study was to analyse different basil extracts, determine the relationship between total phenolic/flavonoid content and antioxidant activity in order to optimize its application in industry. The extraction involved different solvents (ethanol, methanol and water), extraction time (10 and 30 min and 24, 48 and 72 h), plant fragmentation level (0.3 and 2 mm) and the presence or absence of light. Antioxidant activity was investigated by applying spectrophotometric method and measuring the total phenolic and flavonoid content and DPPH radical scavenging activity. The content of total phenolics varied from 5.2 to 185.6 mg of gallic acid equivalents per gram of a dry extract and flavonoids ranged from 0.2 to 35.0 mg of quercetin per gram of a dry extract. All extracts presented a scavenging capacity and IC50 values of DPPH radical inhibition ranged from 0.04 to 12.99 µg/ml. The evaluation of experimental data for eighty basil extracts was performed by chemometric analysis showing good correlation between yield and total phenolic compounds, as well as flavonoid content and inhibition of the DPPH radical.


Assuntos
Ocimum basilicum , Antioxidantes , Flavonoides , Fenóis , Extratos Vegetais/farmacologia
4.
Acta Chim Slov ; 66(4): 821-830, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34057484

RESUMO

Contents of twelve selected bioactive substances and antioxidant potential of Salix caprea L. extracts were compared in its two vegetative organs (bark and leaves) and in terms of different ethanol/water mixtures used for extraction (30-70% aq, ethanol) and extraction time (30 min; 24, 48 and 72 h). The extracts were characterized by High Pressure Liquid Chromatography (HPLC), and total phenolics and flavonoids were determined spectrophotometrically. All secondary metabolites identified in Salix caprea L. extracts (gallic, chlorogenic and vanillic acid, epicatechin, rutin, quercetin and naringenin) were found more accumulated in bark. Salicin and p-hydroxybenzoic acid were detected in bark and ferulic, trans-cinnamic and p-coumaric acid in leaves extracts only. Rutin was most abundant bioactive compound both in bark (1.71 g/100 g of de) and leaves extracts (0.434 g/100 g of de). Bark extract with highest bioactive substances contents was obtained with 70% aq. ethanol as most suitable solvent during extraction time of 48 h. Molecular docking showed salicin to have similar affinity toward COX-2 as acetylsalicylic acid, but lower toward COX-1.

5.
Sci Total Environ ; 634: 780-790, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29653423

RESUMO

We hypothesize that the physical features of river habitats and anthropogenic hydromorphological alterations influence macrophyte communities and lead to habitat fragmentation. Sampling included 1081 contiguous survey units positioned in the main channel and side arms along 588km of the Danube River, along its middle course. To identify habitat fragments, Multivariate Regression Tree analysis (MRT) was applied on macrophyte and environmental data. Indicator species analyses were combined with MRT. To identify habitat fragments on a scale larger than final MRT groups, we set thresholds for an MRT complexity parameter. We identified 20 fine, 7 medium, and 3 large scale habitat fragments. Damming was the main fragmentation agent. Macrophyte communities show continuous variation at all scales of habitat fragmentation. High species diversity indicates major anthropogenic alteration of the river's hydrology and decline of the natural riparian zone. Future studies of the macrophyte communities, and their habitat fragmentation must include more factors (e.g. nutrient status, physicochemical quality of the water, etc.), as well as assessment of the importance of tributaries.

6.
Appl Veg Sci ; 20(1): 143-158, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28356815

RESUMO

QUESTIONS: What are the main floristic patterns in the Pannonian and western Pontic steppe grasslands? What are the diagnostic species of the major subdivisions of the class Festuco-Brometea (temperate Euro-Siberian dry and semi-dry grasslands)? LOCATION: Carpathian Basin (E Austria, SE Czech Republic, Slovakia, Hungary, Romania, Slovenia, N Croatia and N Serbia), Ukraine, S Poland and the Bryansk region of W Russia. METHODS: We applied a geographically stratified resampling to a large set of relevés containing at least one indicator species of steppe grasslands. The resulting data set of 17 993 relevés was classified using the TWINSPAN algorithm. We identified groups of clusters that corresponded to the class Festuco-Brometea. After excluding relevés not belonging to our target class, we applied a consensus of three fidelity measures, also taking into account external knowledge, to establish the diagnostic species of the orders of the class. The original TWINSPAN divisions were revised on the basis of these diagnostic species. RESULTS: The TWINSPAN classification revealed soil moisture as the most important environmental factor. Eight out of 16 TWINSPAN groups corresponded to Festuco-Brometea. A total of 80, 32 and 58 species were accepted as diagnostic for the orders Brometalia erecti, Festucetalia valesiacae and Stipo-Festucetalia pallentis, respectively. In the further subdivision of the orders, soil conditions, geographic distribution and altitude could be identified as factors driving the major floristic patterns. CONCLUSIONS: We propose the following classification of the Festuco-Brometea in our study area: (1) Brometalia erecti (semi-dry grasslands) with Scabioso ochroleucae-Poion angustifoliae (steppe meadows of the forest zone of E Europe) and Cirsio-Brachypodion pinnati (meadow steppes on deep soils in the forest-steppe zone of E Central and E Europe); (2) Festucetalia valesiacae (grass steppes) with Festucion valesiacae (grass steppes on less developed soils in the forest-steppe zone of E Central and E Europe) and Stipion lessingianae (grass steppes in the steppe zone); (3) Stipo-Festucetalia pallentis (rocky steppes) with Asplenio septentrionalis-Festucion pallentis (rocky steppes on siliceous and intermediate soils), Bromo-Festucion pallentis (thermophilous rocky steppes on calcareous soils), Diantho-Seslerion (dealpine Sesleria caerulea grasslands of the Western Carpathians) and Seslerion rigidae (dealpine Sesleria rigida grasslands of the Romanian Carpathians).

7.
Molecules ; 14(1): 1-9, 2008 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-19104481

RESUMO

The taxonomical relationship between Salvia pratensis and S. bertolonii has been unclear for a long time. Salvia bertolonii has alternatively been considered a synonym, a subspecies, a problematic subspecies and a form of Salvia pratensis. However, both these two species are sometimes used in traditional medicine instead of sage (Salvia officinalis) or as an adulteration for the same drug. In order to confirm the status of S. bertolonii, together with the potential identification characteristics for differentiation from sage, both taxa were analyzed through the analysis of their essential oils, together with the micromorphological characteristics of the leaf surface and the anatomy and morphology of the leaves. The obtained results show that there are clear differences in the quantity of essential oil (0.073% for S. pratensis and 0.0016% for S. berolonii). The major compound in the essential oil of S. pratensis was E-caryophyllene (26.4%) while in S. berolonii essential oil caryophyllene oxide was the major component (35.1%). The micromorphological differences are also pronounced in the leaf indumentum (density and distribution of certain types of non-glandular and glandular trichomes). Clear distinction between the investigated Salvia species is also observed in the leaf anatomy (in S. pratensis leaves are thinner, palisade tissue is made of 1-2 layers of cells, and leaves of S. bertolonii are characterized by 2-3 layers of palisade tissue cells, and consequently thicker).


Assuntos
Óleos Voláteis/química , Folhas de Planta/anatomia & histologia , Folhas de Planta/classificação , Salvia/anatomia & histologia , Salvia/classificação , Folhas de Planta/química , Sesquiterpenos Policíclicos , Salvia/química , Sesquiterpenos/análise
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