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1.
Mar Drugs ; 21(11)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37999406

RESUMO

Bacteria are well-known to synthesize high molecular weight polysaccharides excreted in extracellular domain, which constitute their protective microenvironment. Several bacterial exopolysaccharides (EPS) are commercially available for skincare applications in cosmetic products due to their unique structural features, conferring valuable biological and/or textural properties. This review aims to give an overview of bacterial EPS, an important group of macromolecules used in cosmetics as actives and functional ingredients. For this purpose, the main chemical characteristics of EPS are firstly described, followed by the basics of the development of cosmetic ingredients. Then, a focus on EPS production, including upstream and downstream processes, is provided. The diversity of EPS used in the cosmetic industry, and more specifically of marine-derived EPS is highlighted. Marine bacteria isolated from extreme environments are known to produce EPS. However, their production processes are highly challenging due to high or low temperatures; yield must be improved to reach economically viable ingredients. The biological properties of marine-derived EPS are then reviewed, resulting in the highlight of the challenges in this field.


Assuntos
Bactérias , Polissacarídeos Bacterianos , Polissacarídeos Bacterianos/farmacologia , Polissacarídeos Bacterianos/química , Peso Molecular , Temperatura Baixa , Ambientes Extremos
2.
Metabolites ; 13(1)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36677053

RESUMO

Despite several studies on the Ajuga L. genus, the chemical composition of Ajuga pyramidalis, an alpine endemic species, is still largely unknown. The purpose of this study was to therefore deeper describe it, particularly from the phytochemistry and bioactivity perspectives. In that respect, A. pyramidalis was investigated and 95% of the extracted mass of the plant was characterized by chromatography and mass spectrometry. Apart from the already determined chemical compounds, namely, harpagide and 8-O-acetylharpagide, two iridoids, and neoajugapyrin A, a neo-clerodane diterpene, and three polyphenols (echinacoside, verbascoside and teupoloside) were identified for the first time in A. pyramidalis. Incidentally, the first RX structure of a harpagoside derivative is also described in this paper. The extracts and isolated compounds were then evaluated for various biochemical or biological activities; notably a targeted action on the renewal of the epidermis was highlighted with potential applications in the cosmetic field for anti-aging.

3.
Fitoterapia ; 148: 104798, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33307176

RESUMO

The active component extraction from plants is the first crucial step in natural product research. For non-targeted extraction with an objective to isolate and characterize as many compounds as possible, the most classical technique, and the simplest to implement, is the Soxhlet extraction; however, it does not allow retrieving all the compounds from the plant (when it does not additionally cause artifacts during long heating process). The second most used technique is the extraction by successive macerations using solvents of increasing polarity. While this method is frequently used, few studies are available to rationalize and optimize it. Furthermore, this extraction technique requires some enhancement mainly for efficiency, environmental and time constraint reasons. Here, we present an innovative method of successive macerations using a mixture of solvents with the aim of simultaneously improving the yield, the partition of the compounds between the different phases and reducing the volume of extraction solvents. Triphasic systems were prepared by mixing five solvents (n-heptane, ethyl acetate, acetonitrile, butan-1-ol, water) in various proportions. To validate this method, the most efficient triphasic system was subsequently used to perform three successive macerations with a polarity gradient on a model plant before being extended to several alpine plants. Our results showed an overall good yield compared to conventional maceration techniques, while improving phase partition and reducing extraction time and volume of solvents.


Assuntos
Produtos Biológicos/isolamento & purificação , Fracionamento Químico/métodos , Compostos Fitoquímicos/isolamento & purificação , Solventes , Produtos Biológicos/química , Compostos Fitoquímicos/química
4.
NPJ Aging Mech Dis ; 4: 4, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29675264

RESUMO

There is increasing evidence that senescent cells are a driving force behind many age-related pathologies and that their selective elimination increases the life- and healthspan of mice. Senescent cells negatively affect their surrounding tissue by losing their cell specific functionality and by secreting a pro-tumorigenic and pro-inflammatory mixture of growth hormones, chemokines, cytokines and proteases, termed the senescence-associated secretory phenotype (SASP). Here we identified an extract from the plant Solidago virgaurea subsp. alpestris, which exhibited weak senolytic activity, delayed the acquisition of a senescent phenotype and induced a papillary phenotype with improved functionality in human dermal fibroblasts. When administered to stress-induced premature senescent fibroblasts, this extract changed their global mRNA expression profile and particularly reduced the expression of various SASP components, thereby ameliorating the negative influence on nearby cells. Thus, the investigated plant extract represents a promising possibility to block age-related loss of tissue functionality.

5.
J Pharm Pharmacol ; 61(8): 1089-96, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19703353

RESUMO

OBJECTIVES: Cimicifuga racemosa (Actaea racemosa, black cohosh) is used as an anti-inflammatory, antipyretic and analgesic remedy in traditional medicines. The present study focuses on the effects of C. racemosa root extracts on inducible nitric oxide synthase (iNOS) in lipopolysaccharide-stimulated murine macrophages (RAW 264.7). METHODS: C. racemosa rhizome and phosphate-buffered saline extracts were analysed for phenolcarboxylic acids and triterpene glycosides using an HPLC photodiode array/evaporative light-scattering detector system. iNOS was characterised by measurement of iNOS protein (immunoblotting), iNOS mRNA (semiquantitative competitive RT-PCR), nitric oxide production (nitrite levels) and nuclear translocation of nuclear factor-kappaB (p65 subunit) protein. KEY FINDINGS: Incubation of lipopolysaccharide-stimulated macrophages with aqueous C. racemosa extracts (0-6 mg/ml) inhibited nitrite accumulation in a concentration-dependent manner. C. racemosa extracts also reduced iNOS protein expression and iNOS mRNA levels in a dose-dependent manner. C. racemosa extracts did not significantly inhibit iNOS activity and did not affect nuclear translocation of nuclear factor-kappaB (p65 subunit) protein. Incubation with the extract was associated with a concentration-dependent reduction of interferon beta and interferon regulatory factor 1 mRNA. Among the triterpene glycosides, 23-epi-26-deoxyactein was identified as an active principle in C. racemosa extracts. CONCLUSIONS: Extracts from the roots of C. racemosa inhibit nitric oxide production by reducing iNOS expression without affecting activity of the enzyme. This might contribute to the anti-inflammatory activities of C. racemosa.


Assuntos
Cimicifuga/química , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico/biossíntese , Extratos Vegetais/farmacologia , Animais , Ácidos Carboxílicos/isolamento & purificação , Ácidos Carboxílicos/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Lipopolissacarídeos , Macrófagos , Medicina Tradicional , Camundongos , Extratos Vegetais/administração & dosagem , Raízes de Plantas , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Coelhos , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
6.
J AOAC Int ; 90(4): 911-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17760327

RESUMO

The Vaccinium myrtillus fruits (bilberry) are a well-known anthocyanins source, and their extracts are widely used in dietary botanicals and pharmaceutical products for the treatment of vascular and vision disorders. Different analytical methods used for standardization of the bilberry extracts and their preparations are available from pharmacopeias and from the literature. However, the methods reported in the literature do not allow the detection of free anthocyanidins, which are markers of poor product quality. A new liquid chromatography method was developed and validated for the identification and quantification of both anthocyanins and anthocyanidins present in bilberry extracts and products. The method shows a good reproducibility and, due to its high specificity, is suitable to identify unequivocally the botanical raw materials used for manufacturing and to evaluate the extract composition, thus ensuring a high degree of product consistency and quality. Forty typical bilberry preparations belonging to 24 different brands were purchased in the marketplace and evaluated for their quality by using the developed method. Results revealed marked differences among the brands despite a common origin and labeling.


Assuntos
Antocianinas/análise , Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Espectrofotometria Ultravioleta/métodos , Vaccinium myrtillus/metabolismo , Antocianinas/química , Técnicas de Química Analítica/métodos , Frutas , Espectrometria de Massas/métodos , Modelos Químicos , Peso Molecular , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes
7.
J Nat Prod ; 67(12): 2108-10, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15620264

RESUMO

The structure of a new prenylated coumarin (E-omega-benzoyloxyferulenol, 1b) from the Sardinian giant fennel (Ferula communis) has been confirmed by synthesis. The parent compound ferulenol (1a) showed sub-micromolar antimycobacterial activity, which was partly retained in 1b and in the simplified synthetic analogue 3, but diminished in its omega-hydroxy and omega-acetoxy derivatives (1c and 1d, respectively). The outstanding activity of 1a, its low toxicity, and the evidence for definite structure-activity relationships make this prenylated 4-hydroxycoumarin an interesting antibacterial chemotype worth further investigation.


Assuntos
Antibacterianos/isolamento & purificação , Cumarínicos/isolamento & purificação , Ferula/química , Plantas Medicinais/química , Antibacterianos/química , Antibacterianos/farmacologia , Cumarínicos/química , Cumarínicos/farmacologia , Itália , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Relação Estrutura-Atividade
8.
J Chromatogr B Analyt Technol Biomed Life Sci ; 812(1-2): 119-33, 2004 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-15556492

RESUMO

Ginsenosides are considered the main active principles of the famous Chinese traditional medicine "ginseng". For more than 30 years many researchers developed methods for the identification and quantification of ginsenosides in ginseng plant material, extracts and products. Separation of ginsenosides has been achieved using thin layer chromatography (TLC), gas chromatography (GC) and high performance liquid chromatography (HPLC). Among these techniques HPLC is by far the most employed. Ultraviolet (UV), evaporative light scattering (ELSD), fluorescence and, recently, mass spectrometry (MS) were coupled with HPLC for the detection of ginsenosides. The most recent methods are here discussed together with a critical evaluation of the published results. Furthermore new techniques such as near infrared spectroscopy (NIRS) and enzyme immunosassay (EIA) recently used for the determination of ginsenosides will be discussed.


Assuntos
Cromatografia/métodos , Eletroforese Capilar/métodos , Ginsenosídeos/análise , Técnicas Imunoenzimáticas/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos
9.
Fitoterapia ; 75(3-4): 342-54, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15158993

RESUMO

A simple HPLC method was developed to distinguish between 'poisonous' and 'non-poisonous' chemotypes of Ferula communis. The method was performed on a C8 reverse phase analytical column using a binary eluent (aqueous TFA 0.01%-TFA 0.01% in acetonitrile) under gradient condition. The two chemotypes showed different fingerprints. The identification of five coumarins and eleven daucane derivatives by HPLC-diode array detection (HPLC-DAD) and HPLC-MS is described. A coumarin, not yet described, was detected.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cumarínicos/química , Ferula , Fitoterapia , Extratos Vegetais/química , Humanos , Espectrometria de Massas , Raízes de Plantas , Prenilação de Proteína , Reprodutibilidade dos Testes
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