Publications

antioxidant activity of arbutus unedo leaves.	the ethanol and methanol extracts of arbutus unedo leaves were screened for antioxidant activity. the antioxidant activity was determined by an improved assay based on the decolorization of the radical monocation of [2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)] (abts). the ethanol and methanol extract of a. unedo leaves displayed potent antioxidant activity.	2003	12946724
arbutus unedo induces endothelium-dependent relaxation of the isolated rat aorta.	arbutus unedo l. (ericaceae) is used in oriental morocco to treat arterial hypertension. we studied its vasodilator effect and mechanisms of action in vitro. the root aqueous extract of arbutus (0.25 mg/ml) produced a relaxation of noradrenaline-precontracted ring preparations of rat aorta with intact endothelium. relaxation by arbutus did not occur in specimens without endothelium and was inhibited by pretreatment with 100 microm n(g)-methyl-l-arginine (l-nma), 10 microm methylene blue or 50 mi ...	2002	12237817
xylem hydraulic properties of roots and stems of nine mediterranean woody species.	we studied the hydraulic architecture and water relations of nine co-occurring woody species in a spanish evergreen oak forest over the course of a dry season. our main objectives were to: (1) test the existence of a trade-off between hydraulic conductivity and security in the xylem, and (2) establish the safety margins at which the species operated in relation to hydraulic failure, and compare these safety margins between species and tissues (roots vs. stems). our results showed that the relati ...	2002	24599365
seasonal patterns of non-terpenoid c6-c10 voc emission from seven mediterranean woody species.	the seasonal pattern of non-terpenoid c6-c10 voc emission by seven mediterranean woody species (bupleurum fruticosum, cistus albidus, pinus halepensis, arbutus unedo, erica arborea, quercus coccifera, and q. ilex) was studied under field conditions. branch chamber samples were sorbed on carbotrap and analyzed by thermal desorption in combination with gc-ms. these non-terpenoid c6-c10 voc emissions were large, almost of similar magnitude to those of terpenes. overall, maximum values were recorded ...	2001	11592412
quantitative determination of alpha-tocopherol in arbutus unedo by tlc-densitometry and colorimetry.	a quantitative determination of alpha-tocopherol in arbutus unedo leaves was established by tlc-densitometry and colorimetry. data obtained by tlc-densitometry were compared with those obtained by colorimetry. also, the alpha-tocopherol content in leaves collected at different times of the year was studied comparatively. the highest amount of alpha-tocopherol was found in the march collection.	2001	11543963
seasonal patterns of terpene content and emission from seven mediterranean woody species in field conditions.	the seasonal pattern of terpene content and emission by seven mediterranean woody species was studied under field conditions. emission rates were normalized at 30 degrees c and 1000 µmol.m.s pfd (photosynthetic photon flux density). bupleurum fruticosum, pinus halepensis, and cistus albidus stored large amounts of terpenes (0.01-1.77% [dry matter]) with maximum values in autumn and minimum values in spring. they emitted large amounts of terpenes (2-40 µg.g dm.h), but with no clear seasonal trend ...	2000	10636836
seasonal embolism and xylem vulnerability in deciduous and evergreen mediterranean trees influenced by proximity to a carbon dioxide spring.	we investigated how proximity to natural co(2) springs affected the seasonal patterns of xylem embolism in quercus ilex l., quercus pubescens willd., fraxinus ornus l., populus tremula l. and arbutus unedo l., which differ in leaf phenology and wood anatomy. xylem embolism was evaluated in both artificially dehydrated branches and in hydrated apical branches collected at monthly intervals during a 20-month sampling period. initial specific hydraulic conductivity was also evaluated. we found spec ...	1999	12651570
homogentisic acid: a phenolic acid as a marker of strawberry-tree (arbutus unedo) honey.	analysis of organic acids in strawberry-tree (arbutus unedo) honey showed the presence of an unknown acid as the main constituent. this compound was isolated and identified as homogentisic acid (2, 5-dihydroxyphenylacetic acid) by ms and nmr techniques. its average content in honey was 378 +/- 92 mg/kg. analysis of nectar confirmed the floral origin of the compound found in honey. since this acid was not detected in any of the different monofloral honeys, it could be used as a marker of strawber ...	1999	10552766
phytotherapy of hypertension and diabetes in oriental morocco.	in order to select the main medicinal plants used in folk medicine to treat arterial hypertension and/or diabetes, a survey was undertaken in different areas of oriental morocco. the patients (370 women and 256 men) were divided into three groups: diabetics (61%), hypertensives (23%) and hypertensive diabetic persons (16%). on average, 67.51% of patients regularly use medicinal plants. this proportion is perceptibly the same in all groups and does not depend on sex, age and socio-cultural level. ...	1997	9324004
water relations, gas exchange and growth of dominant and suppressed shoots of arbutus unedo l.	basal shoots produced by arbutus unedo l. after cutting at ground level vary in size and growth rate, and are classified accordingly as dominant or suppressed. the suppressed shoots eventually cease growth and die. in this study, we investigated the role of light and water in the competition among shoots of a. unedo. dominant and suppressed shoots of a. unedo showed similar leaf water potentials and tissue water relations over the year, suggesting that water status is not responsible for the lac ...	1995	14965950
water relations, gas exchange, and growth of resprouts and mature plant shoots of arbutus unedo l. and quercus ilex l.	resprout and mature plant shoot growth, leaf water status and gas exchange behavior, tissue nutrient content, flowering, and production were studied for co-occurring shallow-rooted (arbutus unedo l.) and deeprooted (quercus ilex l.) mediterranean tree species at the collserola natural park in northeast spain resprouts showed higher growth rates than mature plant shoots. during fall, no differences in eco-physiological performance of leaves were found, but mobilization of carbohydrates from burls ...	1994	28313978
stomatal patchiness in mediterranean evergreen sclerophylls : phenomenology and consequences for the interpretation of the midday depression in photosynthesis and transpiration.	midday depression of net photosynthesis and transpiration in the mediterranean sclerophylls arbutus unedo l. and quercus suber l. occurs with a depression of mesophyll photosynthetic activity as indicated by calculated carboxylation efficiency (ce) and constant diurnal calculated leaf intercellular partial pressure of co2 (ci). this work examines the hypothesis that this midday depression can be explained by the distribution of patches of either wide-open or closed stomata on the leaf surface, i ...	1992	24178151
a fast method to detect the occurrence of nonhomogeneous distribution of stomatal aperture in heterobaric plant leaves : experiments with arbutus unedo l. during the diurnal course.	pressure infiltration of water into a leaf via the stomatal pores can be used to quickly determine whether all stomata are open, or as recently described for several mesophytic and xerophytic species, whether there is a non-homogeneous distribution of stomatal opening (stomatal patchiness) on the leaf surface. information about this phenomenon is important since the commonly used algorithms for calculation of leaf conductance from water vapor exchange measurements imply homogeneously open stomat ...	1990	28313137
photochemical efficiency of photosystem ii, photon yield of o2 evolution, photosynthetic capacity, and carotenoid composition during the midday depression of net co2 uptake in arbutus unedo growing in portugal.	during the "midday depression" of net co2 exchange in the mediterranean sclerophyllous shrub arbutus unedo, examined in the field in portugal during august of 1987, several parameters indicative of photosynthetic competence were strongly and reversibly affected. these were the photochemical efficiency of photosystem (ps) ii, measured as the ratio of variable to maximum chlorophyll fluorescence, as well as the photon yield and the capacity of photosynthetic o2 evolution at 10% co2, of which the a ...	1989	24212431
continuous basal sprouting from a lignotuber:arbutus unedo l. anderica arborea l., as woody mediterranean examples.	the two dominant species of the corsican mattoral,arbutus unedo l. anderica arborea l., can produce abundant sprouts from the lignotuber not only immediately after fire but also more or less continuously in the absence of major disturbance. the lignotuber appears to be more important during the early stages of development; the result is an increase in the number of sprouts during the 25 years following the establishment of the individuals. later the lignotuber seems to lose the ability to ensure ...	1989	23494355
determination of carbon-reduction-cycle intermediates in leaves of arbutus unedo l. suffering depressions in photosynthesis after application of abscisic acid or exposure to dry air.	gas exchange and contents of photosynthetic intermediates of leaves of arbutus unedo l. were determined with the aim of recognizing the mechanisms of inhibition that were responsible for the "midday depression" of photosynthesis following exposure to dry air, and the decline in photosynthetic capacity following application of abscisic acid (aba). rapidly killed (<0.1 s) leaf samples were taken when gas analysis showed reduced co2 assimilation. determination of the contents of 3-phosphoglyceric a ...	1988	24226409
effect of photosynthetic photon flux density on carboxylation efficiency.	the effect of photosynthetic photon flux density (ppfd) on photosynthetic response (a) to co(2) partial pressures between 35 pascals and co(2) compensation point (gamma) was investigated, especially below ppfd saturation. spinacia oleracea cv ;atlanta,' glycine max cv ;clark,' and arbutus unedo were studied in detail. the initial slope of the photosynthetic response to co(2) ( partial differentiala/ partial differentialc[gamma]) was constant above a ppfd of about 500 to 600 micromoles per square ...	1987	16665640
constituents of the stems of arbutus unedo.	the dried stems of arbutus unedo have been investigated for secondary metabolites. in addition to the previously reported lupeol, ursolic acid, monotropein, unedoside, and stilbericoside, the iridoids geniposide ( 2) and monotropein methyl ester ( 1) have been isolated for the first time from this source. betulinic acid ( 4) has also been isolated for the first time from this plant.	1987	17269002
use of an analytical model to study limitations on net photosynthesis in arbutus unedo under field conditions.	from field gas-exchange measurements on arbutus unedo growing in portugal, parameter values necessary to apply an analytical, physiologicallybased model of c 3 photosynthesis were obtained. the model successfully simulated measured diurnal photosynthetic responses in arbutus during periods without water stress, under both natural and co2-saturating conditions. the model was used to analyze those factors limiting primary productivity during each of the experimental days. due to a large investment ...	1986	28311926
the midday depression of co2 assimilation in leaves of arbutus unedo l.: diurnal changes in photosynthetic capacity related to changes in temperature and humidity.	parts of attached leaves of the sclerophyllous shrub arbutus unedo were subjected to simulated mediterranean days. gas exchange was recorded in order to recognize the causes of the midday depression in co2 assimilation. depressions could be induced in part of a leaf: they were local responses. the co2-saturation curves of photosynthesis, determined during the morning and afternoon maxima of co2 assimilation and during the minimum at midday, established that depressions in co2 assimilation were i ...	1986	24232332
stomatal aperture, photosythesis and water fluxes in mesophyll cells as affected by the abscission of leaves. simultaneous measurements of gas exchange, light scattering and chlorphyll fluorescence.	carbon dioxide exchange, transpiration, chlorophyll fluorescence and light scattering of leaves of lycopersicom esculentum, helianthus annuus and arbutus unedo were measured simultaneously before and after abscission of leaves. scattering of a weak green measuring beam was used to monitor water fluxes across the thylakoid membranes of the mesophyll. when leaves were cut under water, stomata initially closed partially and then occasionally exhibited distinct regulatory oscillations. as stomata cl ...	1986	24240372
effects of humidity during diurnal courses on the co2- and light-saturated rate of net co2 uptake in the sclerophyllous leaves of arbutus unedo.		1985	28311330
effects of temperature at constant air dew point on leaf carboxylation efficiency and co2 compensation point of different leaf types.	the effect of temperature on photosynthesis at constant water-vapor pressure in the air was investigated using two sclerophyll species, arbutus unedo and quercus suber, and one mesophytic species, spinacia oleracea. photosynthesis and transpiration were measured over a range of temperatures, 20-39° c. the external concentration of co2 was varied from 340 μbar to near co2 compensation. the initial slope (carboxylation efficiency, ce) of the photosynthetic response to intercellular co2 concentrati ...	1985	24241315
the responses of stomata and leaf gas exchange to vapour pressure deficits and soil water content : i. species comparisons at high soil water contents.	the responses of photosynthesis, transpiration and leaf conductance to changes in vapour pressure deficit were followed in well-watered plants of the herbaceous species, helianthus annuus, helianthus nuttallii, pisum sativum and vigna unguiculata, and in the woody species having either sclerophyllous leaves, arbutus unedo, nerium oleander and pistacia vera, or mesomorphic leaves, corylus avellana, gossypium hirsutum and prunus dulcis. when the vapour pressure deficit of the air around a single l ...	1984	28311208
diurnal variations in abscisic acid content and stomatal response to applied abscisic acid in leaves of irrigated and non-irrigated arbutus unedo plants under naturally fluctuating environmental conditions.	endogenous abscisic acid content (aba) of arbutus unedo leaves growing under natural conditions in a macchia near sobreda, portugal, was very high (0.25 to 2.3 μg g(1) fresh weight). highest concentrations were found during the very early morning hours and at midday. during the late morning hours and in the late afternoon aba concentrations decreased to between one-third and one-fourth of peak values. the samples for aba content were obtained from both irrigated (ψ between-10 and-25 bar) and non ...	1983	28310657
the control by atmospheric factors and water stress of midday stomatal closure in arbutus unedo growing in a natural macchia.	midday closure of stomata of well-watered (ψ between-10 and-25 bar) or moderately stressed (ψ between-25 and-35 bar) arbutus unedo plants occurs when midday leaf temperatures increase above 30°c and vapor pressure difference between leaf air spaces and the external air increases above approximately 30 mbar/bar. moderate water stress decreases maximum conductance and may result in greater sensitivity to high leaf temperature and vapor pressure dificit, which results in earlier closure and later r ...	1982	28311229
midday stomatal closure in mediterranean type sclerophylls under simulated habitat conditions in an environmental chamber : ii. effect of the complex of leaf temperature and air humidity on gas exchange of arbutus unedo and quercus ilex.	shrubs of the mediterranean sclerophyllous species arbutus unedo and quercus ilex were studied under simulated habitat conditions in an environmental chamber. temperature, humidity, and light intensity were altered stepwise to simulate diurnal changes in conditions similar to those measured in an evergreen macchia in sobreda, portugal. leaves were enclosed in cuvettes which reproduced the growth chamber climate and which allowed measurement of gas exchange. increasing atmospheric stress in the f ...	1981	28310056
midday stomatal closure in arbutus unedo leaves in a natural macchia and under simulated habitat conditions in an environmental chamber.		1980	28309088
[on antibiotically active substances in arbutus unedo l. (strawberry tree)].		1968	4875563
[obtention and identification of lupeol from the strawberry tree (arbutus unedo l.)].		1963	13978339
[arbutus unedo, unused source of vitamins].		1955	13405423
[on arbutus unedo l. ii. quantitative analysis of arbutin and tannins in the leaves of the strawberry tree].		1951	14833915
[arbutus unedo l. i. determination of arbutin in the leaves of the strawberry tree].		1950	14797406
[chemical composition of a mediterranean ericace: arbutus unedo l..].		1950	15434604
studies on carotenoids: the carotenoids of diospyros fruits. ii. the carotenoids of arbutus fruits (arbutus unedo).		1935	16745844
effects of cold stratification and ga3 on germination of arbutus unedo seeds of three provenances.	arbutus unedo is a valuable mediterranean shrub as an ornamental plant as well as fruit tree. fresh fruits of a. unedo are a good source of antioxidants, of vitamins c, e and carotenoids and also are characterized by the high content of mineral elements.	0	28480410