199 research outputs found
Phenolic acids determination by HPLC-DAD-ESI/MS in sixteen different portuguese wild mushrooms species
Analysis of phenolic compounds in sixteen Portuguese wild mushrooms species has been carried out by
high-performance liquid chromatography coupled to photodiode array detector and mass spectrometer
(HPLC–DAD–ESI/MS). No flavonoids were detected in the analysed samples, but diverse phenolic acids
namely protocatechuic, p-hydroxybenzoic and p-coumaric acids, and two vanillic acid isomers were
found and quantified. A related non-phenolic compound, cinnamic acid, was also detected in some samples,
being the only compound found in Cantharellus cibarius (14.97 mg/kg, dry matter), Lycoperdon perlatum
(14.36 mg/kg) and Macrolepiota procera (21.53 mg/kg). p-Hydroxybenzoic acid was found in the
majority of the samples, being the most abundant compound in Agaricus silvicola (238.7 mg/kg). Ramaria
botrytis showed the highest phenolic acids concentration (356.7 mg/kg) due to the significant contribution
of protocatechuic acid (342.7 mg/kg)
Characterization and quantification of phenolic compounds in four tomato (Lycopersicon esculentum L.) farmer’ varieties in Northeastern Portugal homegardens.
Tomato (Lycopersicon esculentum L.) is one of
the most widely consumed fresh and processed vegetables
in the world, and contains bioactive key components. Phenolic
compounds are one of those components and, according
to the present study, farmers’ varieties of tomato
cultivated in homegardens from the northeastern Portuguese
region are a source of phenolic compounds, mainly phenolic
acid derivatives. Using HPLC-DAD-ESI/MS, it was concluded
that a cis p-coumaric acid derivative was the most
abundant compound in yellow (Amarelo) and round
(Batateiro) tomato varieties, while 4-O-caffeolyquinic acid
was the most abundant in long (Comprido) and heart (Coração)
varieties. The most abundant flavonoid was quercetin
pentosylrutinoside in the four tomato varieties. Yellow tomato
presented the highest levels of phenolic compounds
(54.23 μg/g fw), including phenolic acids (43.30 μg/g fw)
and flavonoids (10.93 μg/g fw). The phenolic compounds
profile obtained for the studied varieties is different from
other tomato varieties available in different countries, which
is certainly related to genetic features, cultivation conditions,
and handling and storage methods associated to each
sample
Characterization of phenolic compounds in flowers of wild medicinal plants from Northeastern Portugal.
Crataegus monogyna, Cytisus multiflorus, Malva sylvestris and Sambucus nigra have been used as important medicinal plants in the Iberian Peninsula since a long time ago, and are claimed to have various health benefits. This study aimed to determine the phenolic profile and composition of wild medicinal flowers of those species. The analysis was performed by HPLC-DAD-ESI/MS. Flavonoids, and particularly flavonols and flavones, were the main groups in almost all the studied samples. C. multiflorus sample gave the highest levels of total flavonoids (54.5 mg/g dw), being a chrysin derivative the most abundant flavone found (22.3 mg/g dw). C. monogyna revealed the highest concentration in phenolic acids (5.5 mg/g dw) that were not found in C. multiflorus sample; 5-O-caffeoylquinic acid was the most abundant phenolic acid found in the first species, being a procyanidin trimer also found (1.4 mg/g dw). Kaempferol-3-O-rutinoside (0.84 mg/g dw) and quercetin-3-O-rutinoside (14.9 mg/g dw) were the main flavonols present in M. sylvestris and S. nigra, respectively. Due to the well established antioxidant activity of phenolic compounds, the studied wild medicinal flowers could be selected for processing extracts with health-promoting properties or to be incorporate into functional beverages or products with bioactive properties related to oxidative stress
Phenolic composition and antioxidant activity of Portuguese wild edible greens
This study aimed to determine the phenolic composition and to evaluate the antioxidant activity of wild asparagus, white and black bryony (early shoots in spring). Black bryony revealed the highest antioxidant potential in all the assays (ECso<203 μg/ml), which is compatible to its highest concentration
in phenolic compounds. The main phenolic compounds found in asparagus and black bryony were glycoside derivatives of flavonols (kaempferol, quercetin and isorhamnetin, the latter only found in asparagus) and phenolic acids (sinapic and chlorogenic acid, respectively for asparagus and black bryony). Black bryony revealed the highest content of these compounds. White bryony samplc can be
differentiated from the other two wild edible greens presenting flavones as main compounds being identified glycoside derivatives of luteolin and apigenin
Analysis of phenolic compounds in flowers from wild medicinal plants from northeastern Portugal.
This study aimed to analyse phenolic compounds in wild medicinal flowers of Crataegus monogyna, Cytisus multiflorus, Malva sylvestris and Sambucus nigra, by HPLC-DAD-ESI/MS. Flavonols and flavones were the main groups in almost all the studied samples. C. multiflorus sample gave the highest levels of flavonoids, being a chrysin derivative the most abundant flavone. C. monogyna revealed the highest concentration in phenolic acids that were not found in C. multiflorus; 5-O-caffeoylquinic acid was the most abundant phenolic acid found in the first species, being a procyanidin trimer also found. Kaempferol-3-O-rutinoside and quercetin-3-O-rutinoside were the main flavonols present in M. sylvestris and S. nigra, respectively. The studied flowers could be selected for processing extracts with health-promoting properties or to be incorporated into functional beverages or products with bioactive properties related to oxidative stress.PEst-OE/AGR/UI0690/2011, SFRH/BPD/4609/2008 (L. Barros), Ramón y Cajal (M. Dueñas)
Anthocyanin composition in fig (Ficus carica L.)
[EN] The anthocyanin composition was analysed in fig fruit (Ficus carica L.) from five different varieties (Colar, Cuello de Dama (green),
Cuello de Dama (dark purple), Granilla and Bursa Siyahi). Fifteen anthocyanin pigments were detected, most of them containing
cyanidin (Cy) as aglycone; some pelargonidin (Pg) derivatives were also found. Rutinose and glucose were present as substituting
sugars, as well as acylation with malonic acid. Minor levels of peonidin 3-rutinose (Pn 3-rutinoside) in the pulp were also detected.
Other noticeable aspects in the pigment composition of the fig were the detection of anthocyanidin-derived pigments, namely
5-carboxypyranocyanidin-3-rutinoside, a cyanidin 3-rutinose dimer and five condensed pigments containing C–C linked anthocyanins
(Cy and Pg) and flavanol (catechin and epicatechin) residues. Total anthocyanin content in the skin ranged between 32 and 97 mgg 1 and
between 1.5 and 15 mgg 1 in the pulp. The main anthocyanin in both parts of the fruit was Cy 3-rutinoside (48–81% in skin and 68–79%
in pulp) usually followed by Cy 3-glucoside (5–18% in skin and 10–15% in pulp). Malonyl derivatives were more abundant in the skin
(1.2–6.5%) than in the pulp (1.0–2.6%)
Tuberaria lignosa preparations: influence of drying methods and oral dosage forms on antioxidant properties and phytochemical composition
Many herbal beverages used in folk medicine have pharmacological properties connected with the presence of antioxidants such as phenolic compounds. Tuberaria lignosa (Sweet) Samp. (Cistaceae) is one of the most popular medicinal plants in several regions of the Iberian Peninsula used to prepare herbal infusions or decoctions. In the present work, the effects of drying (freeze or shade-drying) and preparation methods (water infusion or decoction) on
the antioxidant activity and phytochemical composition of wild and commercial samples of Tuberaria lignosa were evaluated. Infusion of the freeze-dried wild sample led to the highest levels of sugars, while infusion of shade-dried
wild sample and decoction of the freeze-dried sample retained the highest ascorbic acid and phenolic compounds levels These two samples revealed the highest antioxidant activity, even higher, in some cases, than trolox Decoctions had lower amounts of disaccharides than infusions, which seemed to be hydrolyzed increasing the content in monosaccharides. Commercial samples showed much lower contents in phenolic compounds, mainly in ellagitanins and flavonoids, as also the lowest antioxidant activity. Data give scientific evidence to folk medicinal uses of Tuberaria lignosa. highlighting the interest of its decoctions and infusions as sources of bioactive compounds (e.g. phenolic compounds and ascorbic acid)
Antioxidant activity, ascorbic acid, phenolic compounds and sugars of wild and commercial Tuberaria lignosa samples: effects of drying and oral preparation methods.
The antioxidant activity and phytochemical composition (ascorbic acid, free sugars and phenolic compounds) of decoctions and infusions of wild and commercial samples of Tuberaria lignosa (Sweet) Samp. (Fam. Cistaceae) aerial parts were evaluated and compared. Among wild samples, the effects of the drying method (freeze or shade-drying) on those parameters were studied. Infusion of the freeze-dried wild sample gave the highest levels of sugars, while infusion of shade-dried wild sample and decoction of the freeze-dried sample presented higher ascorbic acid and phenolic compounds content (including ellagitanins and flavonoids) than the other samples. The last two samples also revealed higher antioxidant activity and, in some cases, even higher than trolox. Decoctions gave lower amounts of disaccharides than infusions, which seemed to be hydrolyzed increasing the content in monosaccharides in the first samples. Commercial samples showed the lowest content in phenolic compounds, mainly in ellagitanins and flavonoids, as also the lowest antioxidant activity. This work gives scientific evidences to the traditional medicinal uses of wild Tuberaria lignosa, highlighting the interest of its decoctions and infusions as bioactive compounds source and functional beverages
Avaliação da bioatividade e caracterização quÃmica de uma espécie de uso tópico: Juglans regia L.
As folhas de Juglans regia L. (nogueira), são consideradas uma fonte de compostos benéficos
para a saúde, sendo amplamente utilizadas na medicina tradicional. Alguns dos compostos
bioativos presentes e, com maior destaque, são os compostos fenólicos (antioxidantes). No
presente estudo, analisou-se a composição em ácidos orgânicos, mono e oligossacáridos, e
tocoferóis nas folhas de nogueira e respetiva decocção (vulgarmente utilizada para aplicações
tópicas). A composição fenólica e a bioatividade foram também avaliadas na decocção e no
extracto metanólico. O ácido málico, a sacarose, o α-tocoferol e os ácidos 3-O-cafeoilquÃnicos e
quercetina O-pentósido foram, respetivamente, o ácido orgânico, dissacárido, isoforma de
tocoferol e compostos fenólicos, mais abundantes. O extrato metanólico apresentou maior
potencial antioxidante e antitumoral do que a decocção; nenhuma das amostras apresentou
toxicidade em culturas de células primárias de fÃgado. Este estudo permitiu uma caracterização
mais completa de compostos fenólicos de folhas de nogueira e, tanto quanto sabemos, esta é a
primeira vez que a presença de procianidinas, derivados de taxifolina e tocoferóis é descrita em
folhas de J. regia
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