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Vitamin E characterization in Castanea sativa Mill. cultivars from three consecutive years: a useful authenticity discrimination factor.
Publication . Barreira, João C.M.; Casal, Susana; Ferreira, Isabel C.F.R.; Pereira, J.A.; Oliveira, Beatriz
Vitamin E profiles of selected (2006-2008) Castanea saliva Miller (chestnut) cultivars (Aveleira, Boaventura, Judia and Longal) belonging to the Protected Designation of Origin "Castanha da Terra Fria" were evaluated. Vitamin E is an important lipophilic antioxidant with essential effccts in living systems against aging, strengthening the immune system and reducing cancer risk, reducing viral load in HIV -infected persons or in the treatment of Parkinson-syndrome. The analyses were conducted in NP-HPLC coupled to a multiwavelenght diode array detector
connected with a fluorescence detector.
Radical scavenging activity and lipid peroxidation inhibition of almond, chestnut and their by-products: a comparative study
Publication . Barreira, João C.M.; Ferreira, Isabel C.F.R.; Oliveira, Beatriz; Pereira, J.A.
Disruption of the balance between reactive oxygen species (ROS) production
and elimination leads to oxidative stress. ROS are known for being implicated in
many cell disorders and in the development of many diseases including
cardiovascular diseases, cancer, atherosclerosis, cataracts, chronic inflammation
or neurodegenerative diseases. Some of these diseases seem to have the same
underlying mechanisms, depending on oxidative processes leading to products
with reactive properties, affecting specific molecular targets in the vascular
system, and cellular DNA.1 To find new natural sources o f bioactive
compounds, the antioxidant properties of almond green barks and fruits,
chestnut skins, leaves and fruits, were evaluated through chemical and
biochemical assays: 2,2-diphenyl- 1-picrylhydrazyl radical scavenging activity,
reducing power, inhibition of P-carotene bleaching, inhibition of oxidative
hemolysis in erythrocytes induced by 2,2 -azobis(2-amidinopropane)dihydrochloride
and inhibition of lipid peroxidation in brain tissue (formation of
thiobarbituric acid reactive substances).
Sugars profiles of different chestnut (Castanea sativa Mill.) and almond (Prunus dulcis) cultivars by HPLC-RI
Publication . Barreira, João C.M.; Pereira, J.A.; Oliveira, Beatriz; Ferreira, Isabel C.F.R.
Sugar profiles of different almond and chestnut
cultivars were obtained by high-performance liquid chromatography
(HPLC), by means of a refractive index (RI)
detector. A solid-liquid extraction procedure was used in
defatted and dried samples. The chromatographic separation
was achieved using a Eurospher 100-5 NH2 column using an
isocratic elution with acetonitrile/water (70:30, v/v) at a flow
rate of 1.0 ml/min. All the compounds were separated in
16 min. The method was optimized and proved to be
reproducible and accurate. Generally, more than 95% of
sugars were identified for both matrixes. Sugars profiles
were quite homogeneous for almond cultivars; sucrose was
the main sugar (11.46±0.14 in Marcona to 22.23±0.59 in
Ferragnes g/100 g of dried weight), followed by raffinose
(0.71±0.05 in Ferraduel to 2.11±0.29 in Duro Italiano),
glucose (0.42±0.12 in Pegarinhos two seeded to 1.47±0.19
in Ferragnes) and fructose (0.11±0.02 in Pegarinhos two
seeded to 0.59±0.05 in Gloriette). Commercial cultivars
proved to have higher sucrose contents, except in the case
of Marcona. Nevertheless, chestnut cultivars revealed a
high heterogeneity. Sucrose was the main sugar in Aveleira
(22.05±1.48), Judia (23.30±0.83) and Longal (9.56± 0.91), while glucose was slightly prevalent in Boa Ventura
(6.63±0.49). The observed variance could serve for intercultivar
discrimination.
Antioxidant potential of chestnut (Castanea sativa L.) and almond (Prunus dulcis L.) by-products.
Publication . Barreira, João C.M.; Ferreira, Isabel C.F.R.; Oliveira, Beatriz; Pereira, J.A.
The antioxidant properties of almond green husks (Cvs. Duro Italiano, Ferraduel, Ferranhês, Ferrastar and Orelha de Mula), chestnut skins and chestnut leaves (Cvs. Aveleira, Boa Ventura, Judia and Longal) were evaluated through several chemical and biochemical assays in order to provide a novel strategy to stimulate the application of waste products as new suppliers of useful bioactive compounds, namely antioxidants. All the assayed by-products revealed good antioxidant properties, with very low EC50 values (lower than 380 μg/mL), particularly for lipid peroxidation inhibition (lower than 140 μg/mL). The total phenols and flavonoids contents were also determined. The correlation between these bioactive compounds and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, reducing power, inhibition of β-carotene bleaching and inhibition of lipid peroxidation in pig brain tissue through formation of thiobarbituric acid reactive substances, was also obtained. Although, all the assayed by-products proved to have a high potential of application in new antioxidants formulations, chestnut skins and leaves demonstrated better results.
Almond (Prunus dulcis) as a good source of health beneficial fatty acids
Publication . Barreira, João C.M.; Casal, Susana; Ferreira, Isabel C.F.R.; Oliveira, Beatriz; Pereira, J.A.
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Funding agency
Fundação para a Ciência e a Tecnologia
Funding programme
SFRH
Funding Award Number
SFRH/BD/29060/2006