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1.
Planta Med ; 90(7-08): 554-560, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38843795

RESUMO

A selective Oxone-induced oxidation of oleocanthal and oleacein, the two main secoiridoids of olive oil, to their bis-oxidized products is described. This protocol is based on a Baeyer-Villiger mechanism and the concentration of Oxone in the final solution. The bis-oxidation of the aldehydic compounds could be extended for the synthesis of various semisynthetic analogs. The obtained acids exhibit strong antioxidant activity, being efficient free radical scavengers.


Assuntos
Aldeídos , Azeite de Oliva , Oxirredução , Aldeídos/química , Azeite de Oliva/química , Antioxidantes/química , Antioxidantes/farmacologia , Fenóis/química , Furanos/química , Monoterpenos Ciclopentânicos/química
2.
Phytother Res ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39120436

RESUMO

Obesity is a major source of morbidity worldwide with more than 2 billion adults being overweight or obese. The incidence of obesity has tripled in the last 50 years, leading to an increased risk for a variety of noncommunicable diseases. Previous studies have demonstrated the positive effects of green leafy vegetables on weight gain and obesity and have attributed these beneficial properties, at least in part, to nitrates and isothiocyanates. Nitrates are converted to nitric oxide (NO) and isothiocyanates are known to release hydrogen sulfide (H2S). Herein, we investigated the effect of extracts and fractions produced from Beta vulgaris and Eruca sativa for their ability to limit lipid accumulation, regulate glucose homeostasis, and reduce body weight. Extracts from the different vegetables were screened for their ability to limit lipid accumulation in adipocytes and hepatocytes and for their ability to promote glucose uptake in skeletal muscle cultures; the most effective extracts were next tested in vivo. Wild type mice were placed on high-fat diet for 8 weeks to promote weight gain; animals receiving the selected B. vulgaris and E. sativa extracts exhibited attenuated body weight. Treatment with extracts also led to reduced white adipose tissue depot mass, attenuated adipocyte size, reduced expression of Dgat2 and PPARγ expression, and improved liver steatosis. In contrast, the extracts failed to improve glucose tolerance in obese animals and did not affect blood pressure. Taken together, our data indicate that extracts produced from B. vulgaris and E. sativa exhibit anti-obesity effects, suggesting that dietary supplements containing nitrates and sulfide-releasing compounds might be useful in limiting weight gain.

3.
Phytochem Anal ; 35(1): 163-183, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37709551

RESUMO

INTRODUCTION: Cannabis sativa L. is attracting worldwide attention due to various health-promoting effects. Extraction solvent type is critical for the recovery of bioactive compounds from the plant, especially cannabinoids. However, the choice of solvent is varied and not adequately warranted elsewhere, causing confusion in involved fields. OBJECTIVE: The present work aimed to investigate the effect of extraction solvent on C. sativa (hemp) with regard to cannabinoid recovery and phytochemical profile of the extracts, considering most of the related solvents. METHODOLOGY: The majority of solvents reported for C. sativa (n = 14) were compared using a representative hemp pool. Quantitative results for major and minor cannabinoids were rapidly and reliably obtained using ultrahigh-performance liquid chromatography coupled with photodiode array detection (UPLC-PDA). In parallel, high-performance thin-layer chromatographic (HPTLC) fingerprinting was employed, involving less toxic mobile phase than in relevant reports. Various derivatisation schemes were applied for more comprehensive comparison of extracts. RESULTS: Differential selectivity towards cannabinoids was observed among solvents. MeOH was found particularly efficient for most cannabinoids, in addition to solvent systems such as n-Hex/EtOH 70:30 and ACN/EtOH 80:20, while EtOH was generally inferior. For tetrahydrocannabinol (THC)-type compounds, EtOAc and n-Hex/EtOAc 60:40 outperformed n-Hex, despite its use in the official EU method. Solvents that tend to extract more lipids or more polar compounds were revealed based on HPTLC results. CONCLUSION: Combining the observations from UPLC quantitation and HPTLC fingerprinting, this work allowed comprehensive evaluation of extraction solvents, in view of robust quality assessment and maximised utilisation of C. sativa.


Assuntos
Canabinoides , Cannabis , Canabinoides/análise , Cannabis/química , Solventes , Cromatografia Líquida de Alta Pressão/métodos , Compostos Fitoquímicos/análise , Extratos Vegetais/química
4.
Planta Med ; 88(9-10): 805-813, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35322394

RESUMO

Secoiridoids is the prominent chemical class of olive oil polar constituents and are characterized by significant biological properties. They are abundant in different chemical forms and relatively high concentrations compared to other components, while prone to oxidation due to their chemical motif. In recent years, oxidized derivatives of secoiridoids have been reported, either as natural constituents of olive oil or as components which are gradually formed in all stages of its production and storage. The mono-oxidized forms of oleocanthal and oleacein named as the respective acids have been recently isolated from olive oil and unambiguously structurally characterized. Other oxidized forms of elenolic acid or more complex secoiridoids, such as those of oleuropein and ligstroside aglycones are also sporadically mentioned in the literature. No further information is provided since they have not been isolated in pure form in order to be accurately identified. Most of the time, they are generally referred as oxidized forms of the parent compounds and commonly identified based on mass spectrometric data. In the current study, the semi-synthesis of the main oxidized olive oil secoiridoids, i.e., oleocanthalic acid, oleaceinic acid, EDA acid, carboxylic form of elenolic acid, carboxylic form of ligstroside aglycon, and carboxylic form of oleuropein aglycon is described starting from the corresponding aldehydic derivatives, using SeO2/H2O2 as oxidative agents. Furthermore, their presence in a number of Greek olive oils was investigated as well, as possible correlation thereof with quality parameters.


Assuntos
Peróxido de Hidrogênio , Iridoides , Ácidos Carboxílicos , Iridoides/química , Azeite de Oliva/química , Oxirredução
5.
Molecules ; 27(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36234713

RESUMO

The bioactive compounds present in the edible products of the olive tree have been extensively studied and their favorable effects on various disease risk factors have been demonstrated. The aim of this study was to perform a comparative analysis of the anti-leishmanial effects of total phenolic fractions (TPFs) derived from extra virgin olive oil with different phenolic contents and diverse quantitative patterns. Moreover, the present study investigated their association with miltefosine, a standard anti-leishmanial drug, against both extracellular promastigotes and intracellular amastigotes of a viscerotropic and a dermotropic Leishmania strain. The chemical compositions of TPFs were determined by high performance liquid chromatography with diode array detection (HPLC-DAD). Analysis of parasite growth kinetics, reactive oxygen species production and apoptotic events were determined by microscopy and flow cytometry. Our results revealed that the presence of oleacein (OLEA) and oleocanthal (OLEO) secoiridoids enhances the anti-leishmanial effect of TPF. The association between TPFs and miltefosine was suggested as being additive in Leishmania infantum and Leishmania major promastigotes, and as antagonistic in intracellular amastigotes, as was evaluated with the modified isobologram method. The obtained data verified that TPFs are bioactive dietary extracts with a strong anti-leishmanial activity and highlighted that fractions that are richer in OLEA and OLEO phenolic compounds possess stronger inhibitory effects against parasites. This study may contribute to improving the therapeutic approaches against leishmaniasis.


Assuntos
Antiprotozoários , Leishmania major , Aldeídos , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Monoterpenos Ciclopentânicos , Iridoides/farmacologia , Azeite de Oliva/química , Fenóis , Fosforilcolina/análogos & derivados , Espécies Reativas de Oxigênio/farmacologia
6.
Molecules ; 26(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063887

RESUMO

The present work describes the use of Centrifugal Partition Chromatography (CPC) for the bio-guided isolation of repellent active volatile compounds from essential oils. Five essential oils (EOs) obtained from three Pinus and two Juniperus species were initially analyzed by gas chromatography-mass spectrometry (GC/MS) and evaluated for their repellent properties against Aedes albopictus. The essential oil from needles of P. pinea (PPI) presented the higher activity, showing 82.4% repellency at a dose of 0.2 µL/cm2. The above EO, together with the EO from the fruits of J. oxycedrus subsp. deltoides (JOX), were further analyzed by CPC using the biphasic system n-Heptane/ACN/BuOH in ratio 1.6/1.6/0.2 (v/v/v). The analysis of PPI essential oil resulted in the recovery of (-)-limonene, guaiol and simple mixtures of (-)-limonene/ß-pheladrene, while the fractionation of JOX EO led to the recovery of ß-myrcene, germacrene-D, and mixtures of α-pinene/ß-pinene (ratio 70/30) and α-pinene/germacrene D (ratio 65/45). All isolated compounds and recovered mixtures were tested for their repellent activity. From them, (-)-limonene, guaiol, germacrene-D as well the mixtures of (-)-limonene/ß-pheladrene presented significant repellent activity (>97% repellency) against Ae. albopictus. The present methodology could be a valuable tool in the effort to develop potent mosquito repellents which are environmentally friendly.


Assuntos
Aedes/efeitos dos fármacos , Cromatografia/métodos , Repelentes de Insetos/isolamento & purificação , Animais , Bioensaio , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Repelentes de Insetos/administração & dosagem , Repelentes de Insetos/farmacologia , Juniperus/química , Óleos Voláteis/química , Pinus/química , Volatilização
7.
Planta Med ; 82(11-12): 1070-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27220071

RESUMO

The Cretan diet, as the basis of the Mediterranean diet, has provided traditional remedies for the general well being of people through the long-established consumption of cooked wild greens and vegetables. The intake of the water decoctions of Cichorium spinosum and Cichorium intybus in the context of the daily dietary regime in Greece has been long associated with "liver detoxifying" properties. In the current study, we performed an in-depth investigation of the water decoctions traditionally prepared from C. spinosum and C. intybus through qualitative UHPLC-HRMS profiling and direct quantification of cichoric and caftaric acid as major antioxidant components of the decoction. In addition, we developed a one-step countercurrent chromatography method for the isolation of the two phenolic acids, along with a sulfoconjugate sesquiterpene lactone present only in the Cretan C. spinosum. All water decoctions were found not to be cytotoxic in human fibroblasts, whereas they all significantly reduced the intracellular reactive oxygen species, which is consistent with the major presence of strong antioxidant compounds such as cichoric acid. This work demonstrates that the intake of these decoctions in doses suggested by Greek traditional use is comparable to the ingestion of a phytomedical preparation of antioxidants. These results contribute to our current knowledge on the beneficial health effect of the Cretan diet.


Assuntos
Antioxidantes/análise , Asteraceae/química , Cichorium intybus/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Antioxidantes/farmacologia , Ácidos Cafeicos/isolamento & purificação , Ácidos Cafeicos/farmacologia , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Dieta Mediterrânea , Humanos , Espectrometria de Massas , Estrutura Molecular , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Succinatos/isolamento & purificação , Succinatos/farmacologia
8.
Planta Med ; 81(12-13): 1205-12, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26218340

RESUMO

Olive mill waste water is the major byproduct of the olive oil industry containing a range of compounds related to Olea europaea and olive oil constituents. Olive mill waste water comprises an important environmental problem in olive oil producing countries, but it is also a valuable material for the isolation of high added value compounds. In this study, an attempt to investigate the secoiridoid content of olive mill waste water is described with the aid of ultrahigh-performance liquid chromatography-electrospray ionization (±)-high-resolution mass spectrometry and centrifugal partition chromatography methods. In total, seven secoiridoid lactones were isolated, four of which are new natural products. This is the first time that a conjugate of hydroxytyrosol and a secoiridoid lactone has been isolated from olive mill waste water and structurally characterized. Furthermore, the range of isolated compounds allowed for the proposal of a hypothesis for the biotransformation of olive secoiridoids during the production of olive mill waste water. Finally, the ability of the representative compounds to reduce the intracellular reactive oxygen species was assessed with the dichlorofluorescein assay in conjunction with the known antioxidant agent hydroxytyrosol.


Assuntos
Lactonas/química , Olea/química , Azeite de Oliva/química , Álcool Feniletílico/análogos & derivados , Antioxidantes/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fluoresceínas , Humanos , Iridoides/química , Iridoides/isolamento & purificação , Lactonas/isolamento & purificação , Azeite de Oliva/isolamento & purificação , Álcool Feniletílico/química , Álcool Feniletílico/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Águas Residuárias/química
9.
Phytochem Anal ; 25(4): 350-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24497327

RESUMO

INTRODUCTION: Nuclear magnetic resonance (NMR) is one of the most commonly used analytical techniques in plant metabolomics. Although this technique is very reproducible and simple to implement, sample preparation procedures have a great impact on the quality of the metabolomics data. OBJECTIVE: Investigation of different sample preparation methods and establishment of an optimised protocol for untargeted NMR-based metabolomics of Vitis vinifera L. wood samples. METHODS: Wood samples from two different cultivars of V. vinifera with well-defined phenotypes (Gamaret and 2091) were selected as reference materials. Different extraction solvents (successively, dichloromethane, methanol and water, as well as ethyl acetate and 7:3 methanol-water (v/v)) and deuterated solvents (methanol-d4, 7:3 chloroform-d-methanol-d4 (v/v), dimethylsulphoxide-d6 and 9:1 dimethylsulphoxide-d6-water-d2 (v/v)) were evaluated for NMR acquisition, and the spectral quality was compared. The optimal extract concentration, chemical shift stability and peak area repeatability were also investigated. RESULTS: Ethyl acetate was found to be the most satisfactory solvent for the extraction of all representative chemical classes of secondary metabolites in V. vinifera wood. The optimal concentration of dried extract was 10 mg/mL and 7:3 chloroform-d-methanol-d4 (v/v) was the most suitable solvent system for NMR analysis. Multivariate data analysis was used to estimate the biological variation and clustering between different cultivars. CONCLUSION: Close attention should be paid to all required procedures before NMR analysis, especially to the selection of an extraction solvent and a deuterated solvent system to perform an extensive metabolomic survey of the specific matrix.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Metabolômica , Vitis/metabolismo , Madeira , Cromatografia Líquida de Alta Pressão , Solventes/química
10.
Molecules ; 19(9): 15042-57, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25244285

RESUMO

Micromelum falcatum, a medicinal plant of the Rutaceae family, has been used in the Traditional Chinese Medicine (TCM) mainly against colds and rheumatoid arthritis. Despite its traditional use the association of its constituents with possible anti-inflammatory activity has not been explored. During this study, a rapid UPLC-ESI(+)-HRMS method was developed for the profiling of M. falcatum leave extracts and the targeted isolation of coumarin constituents. Based on chromatographic, spectroscopic and spectrometric features several 7-oxygenated coumarin derivatives were detected. After targeted isolation, eight coumarins, among them three new natural products, namely microfalcrin, microcoumaririn and micromelosidester, were purified using semi-preparative HPLC and unambiguously identified by 1 and 2D NMR. Furthermore, important spectrometric characteristics were revealed based on the HRMS and HRMS/MS spectra of the isolated 7-oxygenated coumarins facilitating their identification in complex mixtures. Finally, the anti-inflammatory properties of the extracts and representative compounds were evaluated by measuring the inhibition of the pro-inflammatory mediator NF-κB induction and nitric oxide (NO) production.


Assuntos
Cromatografia Líquida/métodos , Cumarínicos/análise , Rutaceae/química , Espectrometria de Massas em Tandem/métodos , Espectrofotometria Ultravioleta
11.
PLoS One ; 19(8): e0300278, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39208286

RESUMO

Lyciasalamandra species, like most amphibians, secrete a wide array of compounds from their granular and mucous skin glands, including the internally synthesized samandarine alkaloids, making their skin a complex organ performing a variety of functions. Lyciasalamandra helverseni and L. luschani basoglui are insular endemics of the Dodecanese islands of SE Greece, bearing distinct isolated populations, with well-documented phylogenetic profiles. Here, we employ a metabolomics approach, utilizing UPLC-ESI-HRMS/MS data of the skin secretions sampled from a number of specimens found in the islands of Karpathos, Kasos and Kastellorizo, in an effort to reveal aspects of their chemistry and diversity across populations. The results indicated statistically significant variation between all taxa examined, based on various secreted compounds. The underlying factors of variation highlighted by the multivariate analysis were differences in samandarine and other alkaloid content as well as in animal size. Metabolite annotation, based on dereplication tools and most importantly HRMS and HRMS/MS spectra, yielded a number of known samandarine alkaloids, reported for the first time in the currently studied Lyciasalamandra species. We also present documentation for novel members of the samandarine alkaloid family, as well as preliminary evidence for a possible dietary alkaloid sequestration. This work can set the basis for further research of this often-neglected endemic species of the Salamandridae, as well as the structural investigation of the samandarine alkaloid group.


Assuntos
Alcaloides , Metaboloma , Pele , Urodelos , Animais , Alcaloides/metabolismo , Alcaloides/análise , Grécia , Pele/metabolismo , Pele/química , Urodelos/metabolismo , Dieta , Metabolômica/métodos
12.
Phytochemistry ; 222: 114076, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38570005

RESUMO

The high value of fiber-type Cannabis sativa L. (hemp) due to its phytochemicals has yet to be fully recognized and leveraged. Besides cannabidiol (CBD), which is the most prevalent non-psychoactive cannabinoid, hemp contains numerous other cannabinoids with unexplored bioactivities, in addition to various compound classes. Previous works have aimed to correlate chemical profiles of C. sativa inflorescences with important parameters, mostly based on experiments under controlled conditions. However, mapping studies that explore the phytochemical diversity of hemp in a more realistic context are crucial to guide decisions at multiple levels, especially in areas where hemp cultivation was recently re-authorized, including Mediterranean countries. In this work, a powerful strategy was followed to map the phytochemical diversity of cultivated hemp in Greece, being the first study of its kind for this environment. A panel of 98 inflorescence samples, covering two harvesting years, eleven geographical regions and seven commonly used EU varieties, were studied using a combination of targeted and untargeted approaches. Quantitative results based on UPLC-PDA revealed relatively constant CBD/THC (total) ratios, while profiling by LC-HRMS effectively probed the phytochemical variability of samples, and led to the annotation of 88 metabolites, including a multitude of minor cannabinoids. Multivariate analysis substantiated a strong effect of harvesting year in sample discrimination and related biomarkers were revealed, belonging to fatty acids and flavonoids. The effect of geographical region and, especially, variety on chemical variation patterns was more intricate to interpret. The results of this work are envisioned to enhance our understanding of the real-world phytochemical complexity of C. sativa (hemp), with a view to maximized utilization of hemp for the promotion of human well-being.


Assuntos
Cannabis , Compostos Fitoquímicos , Cannabis/química , Grécia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Canabinoides/química , Canabinoides/análise
13.
Cell Mol Neurobiol ; 33(1): 147-54, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23053546

RESUMO

Over the past decade, intense focus has been dedicated on investigating processes involved in the proteolysis of amyloid precursor protein (AßPP) and ß-amyloid (Aß) peptide metabolism, as possible targets for Alzheimer's disease (AD) therapy. To this goal, considerable research has been targeted on potential therapeutic use of compounds promoting non-amyloidogenic processing of AßPP. One of these compounds, oleuropein, a polyphenol constituent of extra virgin olive oil exhibiting a wide range of pharmacological properties, was shown to interact non-covalently with Aß, an interaction that might be related to a potential protective role of oleuropein against Aß aggregation. In the present study, it was demonstrated that oleuropein treatment of HEK293 cells stably transfected with the isoform 695 of human AßPP (APP695) leads to markedly elevated levels of sAPPα and to significant reduction of Aß oligomers. These effects were associated with increased activity of matrix metalloproteinase 9 (MMP-9), whereas no significant alterations in the expression of secretases TACE, ADAM-10 or BACE-1 were observed. Similar results were obtained using the human neuroblastoma cell line SK-N-SH. The experimental data reveal an anti-amyloidogenic effect of oleuropein and suggest a possible protective role for oleuropein against AD, extending the spectrum of beneficial properties of this naturally occurring polyphenol.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Antioxidantes/farmacologia , Olea , Polifenóis/farmacologia , Piranos/farmacologia , Secretases da Proteína Precursora do Amiloide/farmacologia , Linhagem Celular Tumoral , Humanos , Glucosídeos Iridoides , Iridoides
14.
Cells ; 13(1)2023 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-38201274

RESUMO

Gentiopicroside (GPS) is a leading component of several plant species from the Gentianaceae botanical family. As a compound with plenty of biological activities and a component of herbal drugs, GPS has an important role in the regulation of physiological processes in humans. The results of recently published scientific studies underline a meaningful role of this molecule as an active factor in metabolic pathways and mechanisms, which may have an influence in the treatment of different diseases, including digestive tract disorders, malignant changes, neurological disorders, microbial infections, bone formation disorders, inflammatory conditions, and others. This review aims to collect previously published reports on the biological properties of GPS as a single compound that were confirmed by in vitro and in vivo studies, and to draw attention to the newly discovered role of this bitter-tasting secoiridoid. Thanks to these properties, the research on this substance could be revisited.


Assuntos
Doenças Ósseas , Glucosídeos Iridoides , Humanos , Glucosídeos Iridoides/farmacologia , Osteogênese , Projetos de Pesquisa
15.
Biomedicines ; 11(8)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37626746

RESUMO

Oleuropein (OLE), a main constituent of olives, displays a pleiotropic beneficial dynamic in health and disease; the effects are based mainly on its antioxidant and hypolipidemic properties, and its capacity to protect the myocardium during ischemia. Furthermore, OLE activates the peroxisome proliferator-activated receptor (PPARα) in neurons and astrocytes, providing neuroprotection against noxious biological reactions that are induced following cerebral ischemia. The current study investigated the effect of OLE in the regulation of various neural plasticity indices, emphasizing the role of PPARα. For this purpose, 129/Sv wild-type (WT) and Pparα-null mice were treated with OLE for three weeks. The findings revealed that chronic treatment with OLE up-regulated the brain-derived neurotrophic factor (BDNF) and its receptor TrkB in the prefrontal cortex (PFC) of mice via activation of the ERK1/2, AKT and PKA/CREB signaling pathways. No similar effects were observed in the hippocampus. The OLE-induced effects on BDNF and TrkB appear to be mediated by PPARα, because no similar alterations were observed in the PFC of Pparα-null mice. Notably, OLE did not affect the neurotrophic factors NT3 and NT4/5 in both brain tissues. However, fenofibrate, a selective PPARα agonist, up-regulated BDNF and NT3 in the PFC of mice, whereas the drug induced NT4/5 in both brain sites tested. Interestingly, OLE provided neuroprotection in differentiated human SH-SY5Y cells against ß-amyloid and H2O2 toxicity independently from PPARα activation. In conclusion, OLE and similar drugs, acting either as PPARα agonists or via PPARα independent mechanisms, could improve synaptic function/plasticity mainly in the PFC and to a lesser extent in the hippocampus, thus beneficially affecting cognitive functions.

16.
Fitoterapia ; 170: 105648, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37562489

RESUMO

Pistacia lentiscus L. var. Chia belongs to the Anacardiaceae family, and it is cultivated only in the south part of Chios island, in Greece. Even though it is renowned for its unique resin, Chios mastic gum (CMG), the tree leaves have also been used in traditional medicine, while the annual pruning generates a large biomass of unused by-products. Thus, the aim of the present study was the detailed phytochemical investigation of P. lentiscus var. Chia leaves towards the search of antimicrobial agents. UPLC-HRMS & HRMS/MS based dereplication methods led to the detailed characterization of the aqueous leaf extract. In addition, twelve compounds were isolated and purified from the methanol extract and were identified using spectroscopic and spectrometric methods (NMR, HRMS) belonging to phenolic acids, tannins, flavonoids and terpenes, with the most interesting being 2-hydroxy-1,8-cineole ß-D-glucopyranoside which was isolated for the first time in the Anacardiaceae family. Remarkably, based on NMR data, methanol and aqueous extracts were found to be particularly rich in shikimic acid, a valuable building block for the pharmaceutical industry, for instance in the synthesis of the active ingredient of Tamiflu®, oseltamivir. Finally, extracts (EtOAc, MeOH, H2O) and major compounds i.e., shikimic acid, 2-hydroxy-1,8-cineole ß-D-glucopyranoside and myricitrin were evaluated for their antimicrobial properties. MeOH and H2O mastic leaf extracts as well as myricitrin and, particularly, 2-hydroxy-1,8-cineole ß-D-glucopyranoside showed significant selective activity against pathogenic Mucorales, but not against Aspergilli (Aspergillus nidulans, Aspergillus fumigatus), Candida albicans or bacteria (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis).


Assuntos
Anti-Infecciosos , Pistacia , Pistacia/química , Ácido Chiquímico , Metanol , Estrutura Molecular , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Resina Mástique , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia , Eucaliptol
17.
Plants (Basel) ; 12(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36903954

RESUMO

Oxidative damages are responsible for many adverse health effects and food deterioration. The use of antioxidant substances is well renowned, and as such, much emphasis is placed on their use. Since synthetic antioxidants exhibit potential adverse effects, plant-derived antioxidants are a preferable solution. Despite the myriads of plants that exist and the fact that numerous studies have been carried out so far, there are many species that have not been examined so far. Many plants under research exist in Greece. Trying to fill this research gap, the total phenolics content and antioxidant activity of seventy methanolic extracts from parts of Greek plants were evaluated. The total phenolics content was measured by the Folin-Ciocalteau assay. Their antioxidant capacity was calculated by the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging test, the Rancimat method based on conductometric measurements, and the thermoanalytical method DSC (Differential Scanning Calorimetry). The tested samples were obtained from several parts of fifty-seven Greek plant species belonging to twenty-three different families. Both a remarkably high phenolic content (with gallic acid equivalents varying between 311.6 and 735.5 mg/g of extract) and radical scavenging activity (IC50 values ranged from 7.2 to 39.0 µg/mL) were found in the extract of the aerial parts of Cistus species (C. creticus subsp. creticus, C. creticus subsp. eriocephalus, C. monspeliensis, C. parviflorus and C. salviifolius), Cytinus taxa (C. hypocistis subsp. hypocistis, C. hypocistis subsp. orientalis and C. ruber), and Sarcopoterium spinosum. Furthermore, the sample of Cytinus ruber showed the highest protection factor (PF = 1.276) regarding the Rancimat method, which was similar to that of butylated hydroxytoluene (BHT) (PF = 1.320). The results indicated that these plants are rich in antioxidant compounds, potentiating their use either as food additives to enhance the antioxidant properties of food products, or protect them from oxidation, or as sources for the preparation of food supplements with antioxidant properties.

18.
Planta Med ; 78(10): 951-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22673832

RESUMO

The dual specificity tyrosine-phosphorylation-regulated kinase DYRK1A possesses diverse roles in neuronal development and adult brain physiology, and increased activity has been linked to neurodegenerative diseases. Very few inhibitors of this kinase have been reported up to now. Screening of a library of > 900 plant and fungal extracts afforded 25 extracts with IC50s < 10 µg/mL against DYRK1A. To identify the active constituents, the extracts were submitted to a process integrating physicochemical data with biological information, referred to as HPLC-based activity profiling. Follow-up investigation of four extracts led to the targeted isolation of harmine (1, IC50 0.022 µM) from Peganum harmala, emodin (3, IC50 4.2 µM) from Cassia nigricans, kaempferol (4, IC50 0.91 µM) from Cuscuta chinensis, and 3,8-di-O-methylherbacetin (11, IC50 8.6 µM), 3,3',4'-tri-O-methylmyricetin (12, IC50 7.1 µM) and ombuin (15, IC50 1.7 µM) from Larrea tridentata as the active constituents. Active extracts and compounds were also tested on the closely related cdc2-like kinase CLK1. Finally, the selectivity profile of compounds was evaluated by including other members of the DYRKs and CLKs families. While the flavonoids and emodin did not show significant differences in the potency of their activities, harmine (1) was most active against DYRK1A, CLK1, and CLK4, and less potent against the other kinases, with selectivity ranging from 2- to 20-fold.


Assuntos
Extratos Vegetais/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Animais , Cassia/química , Cromatografia Líquida de Alta Pressão/métodos , Cuscuta/química , Emodina/química , Emodina/isolamento & purificação , Emodina/farmacologia , Ativação Enzimática , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Fungos/química , Harmina/química , Harmina/isolamento & purificação , Harmina/farmacologia , Humanos , Concentração Inibidora 50 , Larrea/química , Espectroscopia de Ressonância Magnética , Camundongos , Peganum/química , Extratos Vegetais/química , Folhas de Planta/química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/isolamento & purificação , Sementes/química , Quinases Dyrk
19.
Pharmaceuticals (Basel) ; 15(12)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36558964

RESUMO

Medicinal plants have long been recognized as a tremendous source of candidate compounds for the development of pharmaceuticals, including anti-viral agents. Herein, we report the identification of anti-influenza virus activity in non-polar Primula veris L. subsp. veris extracts. We show that P. veris subsp. veris flower extracts, obtained using supercritical fluid or ultrasound-based extraction, possess virucidal/virus inactivation properties and confer prophylactic and therapeutic effects against influenza virus-induced cytolysis in vitro. By GC-MS and UPLC-HRMS analysis of non-polar P. veris subsp. veris extracts we identified terpenes, flavones, tocopherols, and other classes of phytochemicals with known or putative anti-influenza properties. In silico prediction of cellular functions and molecular pathways affected by these phytochemicals suggests putative effects on signal transduction, inflammasome, and cell death pathways that are relevant to influenza virus pathogenesis. Combining P. veris subsp. veris with extracts of medicinal plants with proven anti-influenza activity such as Echinacea purpurea (L.) Moench and Cistus creticus L. subsp. creticus achieves an impressive protective effect against infection by influenza virus H1N1 in vitro and reduced progeny virus production by infected cells. Collectively, these findings uncover a previously uncharted biological property of non-polar P. veris flower extracts that warrants further studies to assess clinical efficacy.

20.
Biomolecules ; 13(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36671450

RESUMO

Olive pomace is the main by-product generated by the olive oil production process. Although toxic to the environment, olive pomace is an important source of natural antioxidants due to its high content of phenolic compounds. The aim of the current study is to maximize the extraction yields of the main phenolic compounds present in olive pomace using innovative green technologies. For this purpose, the present work is divided into two parts. The first part is based on a solubility study of targeted phenolic compounds in various ethanol/water ratios at two different temperatures (20 °C and 50 °C). A computational prediction using COSMO-RS software was applied for the calculation of eventual solubility, which was subsequently confirmed by practical experiments. The determination of the optimal extraction conditions of solvent ratio (EtOH/H2O) (60:40 v/v) and temperature (50 °C) led to the second part of the work, which concerns the intensification of extraction yields. Furthermore, various green extractions using innovative technologies, including accelerated solvent extraction (ASE), ultrasound with its both system (probe (UAE-P) and bath (UAE-B)), bead milling (BM) and microwave (MAE), were carried out and then compared to conventional maceration (CM). Results showed that ASE was the most effective method for extracting phenolic compounds from dried olive pomace powder (5.3 milligrams of tyrosol equivalent (TE) per gram of dried olive pomace powder (DOP)) compared to CM (3.8 mg TE/g DOP).


Assuntos
Olea , Pós , Fenóis , Solventes , Etanol
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