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1.
Molecules ; 26(21)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34771028

RESUMO

Helichrysum italicum is a medicinal plant from the Mediterranean area, widely used in traditional medicine for its anti-inflammatory, antibacterial and antioxidant properties and for its preventive effects on microcirculation diseases. Due to these properties, it finds large applications in cosmetic, food and pharmaceutical fields. Additionally, hydroalcoholic extracts and mother tinctures based on H. italicum represent products with a high commercial value, widely distributed not only in drug stores but also on on-line markets. The different extraction procedures used can greatly affect the fingerprints of the extracts, resulting in a different qualitative or quantitative profile of the chemical constituents responsible for biological activity. The aim of the present study was to characterize the composition of bioactive compounds present in water-ethanol and glycerol extracts of H. italicum derived food supplements. Metabolite profiles of the extracts were obtained by 1H NMR experiments and data were processed by multivariate statistical analysis to highlight differences in the extracts and to evidence the extracts with the highest concentrations of bioactive metabolites. In detail, this work highlights how derived food supplements of H. italicum obtained using ethanol-water mixtures ranging from 45% to 20% of ethanol represent the products with the highest amount of both primary (amino acids) and secondary metabolites including 3,4-dicaffeoylquinic acid (9), chlorogenic acid (10), 3,5-dicaffeoylquinic acid (11), and kaempferol 3-O-glucopyranoside (12). Moreover, it is evident that the use of an ethanol-water mixture 20:80 is the most suitable method to afford the highest number of phenolic compounds, while food-derived supplements obtained by glycerol extraction are characterized by a high amount of ß-glucose and α-glucose and a low content of phenolic compounds.


Assuntos
Suplementos Nutricionais/análise , Helichrysum/metabolismo , Metabolômica , Extratos Vegetais/metabolismo , Glicerol/química , Helichrysum/química , Extratos Vegetais/análise , Espectroscopia de Prótons por Ressonância Magnética
2.
PLoS One ; 8(11): e79043, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24260149

RESUMO

BACKGROUND: Helichrysum italicum (Asteraceae) is a small shrub endemic to the Mediterranean Basin, growing in fragmented and diverse habitats. The species has attracted attention due to its secondary metabolite content, but little effort has as yet been dedicated to assessing the genetic and metabolite diversity present in these populations. Here, we describe the diversity of 50 H. italicum populations collected from a range of habitats in Sardinia. METHODS: H. italicum plants were AFLP fingerprinted and the composition of their leaf essential oil characterized by GC-MS. The relationships between the genetic structure of the populations, soil, habitat and climatic variables and the essential oil chemotypes present were evaluated using Bayesian clustering, contingency analyses and AMOVA. KEY RESULTS: The Sardinian germplasm could be partitioned into two AFLP-based clades. Populations collected from the southwestern region constituted a homogeneous group which remained virtually intact even at high levels of K. The second, much larger clade was more diverse. A positive correlation between genetic diversity and elevation suggested the action of natural purifying selection. Four main classes of compounds were identified among the essential oils, namely monoterpenes, oxygenated monoterpenes, sesquiterpenes and oxygenated sesquiterpenes. Oxygenated monoterpene levels were significantly correlated with the AFLP-based clade structure, suggesting a correspondence between gene pool and chemical diversity. CONCLUSIONS: The results suggest an association between chemotype, genetic diversity and collection location which is relevant for the planning of future collections aimed at identifying valuable sources of essential oil.


Assuntos
Ecossistema , Pool Gênico , Variação Genética , Helichrysum/genética , Helichrysum/metabolismo , Óleos Voláteis/metabolismo , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Itália
3.
J Photochem Photobiol B ; 128: 50-7, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24007865

RESUMO

The aim of our study was to investigate the photoprotective activity and photostability efficacy of sunscreen formulations containing Helichrysum arenarium, Sambucus nigra, Crataegus monogyna extracts and their combination. UV transmission of the emulsion films was performed by using diffuse transmittance measurements coupling to an integrating sphere. In vitro photoprotection and photostability efficacy were evaluated according to the following parameters: sun protection factor (SPF), UVA protection factor (PF-UVA), UVA/UVB ratio and critical wavelength (λc) before and after UV irradiation. The results obtained show that the formulations containing polyphenols fulfill the official requirements for sunscreen products due to their broad spectrum of UV protection combined with their high photostability and remarkable antioxidant properties. Therefore H. arenarium, S. nigra, C. monogyna extracts represent useful additives for cosmetic formulation.


Assuntos
Crataegus/química , Helichrysum/química , Extratos Vegetais/química , Sambucus nigra/química , Protetores Solares/química , Raios Ultravioleta , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Cosméticos , Crataegus/metabolismo , Estabilidade de Medicamentos , Emulsões/química , Flavonoides/análise , Helichrysum/metabolismo , Extratos Vegetais/isolamento & purificação , Sambucus nigra/metabolismo , Espectrofotometria , Fator de Proteção Solar , Protetores Solares/isolamento & purificação
4.
Pak J Pharm Sci ; 26(3): 599-604, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23625436

RESUMO

Helichrysum has long been used medicinally, proving to be beneficial in treatment of acne, asthma, bronchitis and circulatory problems, and lymphatic system diseases. The objective of this research was to study the antioxidant and antibacterial activities and chemical composition of the compounds derived from the stems and roots of cultivated H. oligocephalum using gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS). The primary components found in the stem oil were ortho-vanillin (51.0%) and carvacrol (16.0%), and those found in the root oil were 1,8-cineole (30.6%) and isobornyl acetate (13.9%). Stem and root oils of H. oligocephalum demonstrated antibacterial activity, particularly in relation to Gram-positive bacteria. In a ß-carotene/linoleic acid bleaching assay, the root oil of H. oligocephalum demonstrated an antioxidant effect. Antioxidant capacity measured with 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was 1205.0 for the stem oil and 722.8 µg/ml for the root oil.


Assuntos
Helichrysum/química , Helichrysum/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Caules de Planta/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cimenos , Bactérias Gram-Positivas/efeitos dos fármacos , Irã (Geográfico) , Monoterpenos/química , Monoterpenos/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia
5.
Int J Mol Sci ; 10(11): 4990-5001, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-20087473

RESUMO

We evaluated the in vitro antioxidant property and phytochemical constituents of the aqueous crude leaf extract of Helichrysum pedunculatum. The scavenging activity on superoxide anions, DPPH, H2O2, NO and ABTS; and the reducing power were determined, as well as the flavonoid, proanthocyanidin and phenolic contents of the extract. The extract exhibited scavenging activity towards all radicals tested due to the presence of relatively high total phenol and flavonoids contents. Our findings suggest that H. pedunculatum is endowed with antioxidant phytochemicals and could serve as a base for future drugs.


Assuntos
Antioxidantes/química , Helichrysum/química , Extratos Vegetais/química , Polifenóis/química , Antioxidantes/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Helichrysum/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Polifenóis/isolamento & purificação , Proantocianidinas/química , Proantocianidinas/isolamento & purificação , Água/química
6.
Ann Bot ; 102(1): 31-7, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18436550

RESUMO

BACKGROUND AND AIMS: Helichrysum bracteatum is called an 'eternal flower' and has large, coloured, scarious bracts. These maintain their aesthetic value without wilting or discoloration for many years. There have been no research studies of cell death or cell morphology of the scarious bract, and hence the aim of this work was to elucidate these characteristics for the bract of H. bracteatum. METHODS: DAPI (4'6-diamidino-2-phenylindol dihydrochloride) staining and fluorescence microscopy were used for observation of cell nuclei. Light microscopy (LM), transmission electron microscopy (TEM) and polarized light microscopy were used for observation of cells, including cell wall morphology. KEY RESULTS: Cell death occurred at the bract tip during the early stage of flower development. The cell wall was the most prominent characteristic of H. bracteatum bract cells. Characteristic thickened secondary cell walls on the inside of the primary cell walls were observed in both epidermal and inner cells. In addition, the walls of all cells exhibited birefringence. Characteristic thickened secondary cell walls have orientated cellulose microfibrils as well as general secondary cell walls of the tracheary elements. For comparison, these characters were not observed in the petal and bract tissues of Chrysanthemum morifolium. CONCLUSIONS: Bracts at anthesis are composed of dead cells. Helichrysum bracteatum bracts have characteristic thickened secondary cell walls that have not been observed in the parenchyma of any other flowers or leaves. The cells of the H. bracteatum bract differ from other tissues with secondary cell walls, suggesting that they may be a new cell type.


Assuntos
Parede Celular/metabolismo , Flores/metabolismo , Helichrysum/metabolismo , Morte Celular , Parede Celular/ultraestrutura , Flores/citologia , Flores/ultraestrutura , Helichrysum/citologia , Helichrysum/ultraestrutura , Microfibrilas/metabolismo , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Microscopia de Polarização
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