Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
Add more filters










Publication year range
1.
J Food Sci ; 75(2): S115-9, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20492256

ABSTRACT

Dry legumes are staple and potentially functional food, being a good source of polyphenols, flavonoids, and antioxidant activity. The objective of this study was to determine the total polyphenol content (TPC), total flavonoid content (TFC), and their relation with antioxidant capacity in 17 chickpea lines having colored seed coats (black, red, brown, green, rubiginous, gray, yellow, cream, or beige). The seed coat usually contains more than 95% of these compounds. In this study, both TPC and TFC varied significantly among different lines and were highly correlated to antioxidant activity. Colored seeds contained up to 13-, 11-, and 31-fold more TPC, TFC, and antioxidant activity, respectively, than cream- and beige-color seeds. Thus, colored chickpea could be a potentially functional food in addition to its traditional role of providing dietary proteins and dietary fibers.


Subject(s)
Antioxidants/analysis , Cicer/chemistry , Flavonoids/analysis , Phenols/analysis , Food Analysis/methods , Polyphenols
2.
Biomacromolecules ; 7(11): 2971-82, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17096521

ABSTRACT

Intercellular adhesion in some parenchyma becomes strengthened in response to stress. The present study provides an approach to investigate this phenomenon (usually attributed to pectin methyl esterase and binding of Ca(2+) and/or rhamnogalacturonan-II-borate) through reliable stress simulation by probing organic acid molecules in potato tuber parenchyma. Short-chain monocarboxylic acids induce consistent intercellular adhesion strengthening (3.8-5.3 newton) at pH >or= 3 < pK(a), where pectin methyl esterase activity and Ca(2+) or borate binding are limited, and vice versa at pH > pK(a) with a strength of 1.4-2.0 newton as compared to 0.3-0.4 newton for the nonincubated control. Strengthening of intercellular adhesion is characterized by prominent staining of pectin and protein and immunogold labeling of pectin in the cell wall and the middle lamellar complex, particularly after boiling. Pectin confers strengthening to the primary cell wall, as reflected by: (i) prominent immunogold labeling following boiling; and (ii) puncturing macerated cells by starch gelatinization pressure after enzymatic pectin removal.


Subject(s)
Cell Adhesion , Organic Chemicals/pharmacology , Solanum tuberosum/physiology , Acids/pharmacology , Calcium/metabolism , Carboxylic Ester Hydrolases/metabolism , Cell Wall/enzymology , Cell Wall/metabolism , Hydrogen-Ion Concentration , Microscopy, Electron , Solanum tuberosum/enzymology
3.
Biomacromolecules ; 7(3): 937-44, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16529434

ABSTRACT

Intercellular adhesion strengthening, a phenomenon that compromises the texture and the edible quality of potatoes (Solanum tuberosum L.), has been induced reproducibly by exposure to low-pH acetic acid solutions under tissue culture conditions. The resulting parenchyma tissues have been examined by solid-state nuclear magnetic resonance (NMR) in order to characterize the biopolymer(s) thought to be associated with this syndrome. Cross polarization-magic angle spinning (CPMAS) (13)C NMR has been used to establish the presence of a polyphenol-suberin-like aromatic-aliphatic polyester within an abundant cell wall polysaccharide matrix in potato tubers that exhibit hardening due to strengthened intercellular adhesion. Dipolar dephasing and CP chemical shift anisotropy experiments suggest that the aromatic domain is composed primarily of guaiacyl and sinapyl groups. Two-dimensional wide-line separation experiments show that the biopolymer associated with parenchyma hardening contains rigid polysaccharide cell walls and mobile aliphatic long-chain fatty acids; (1)H spin diffusion experiments show that these flexible aliphatic chains are proximal to both the phenolics and a subpopulation of the cell wall polysaccharides. Finally, high-resolution MAS NMR of parenchyma samples swelled in DMSO in conjunction with two-dimensional through-bond and through-space NMR spectroscopy provides evidence for covalent linkages among the polysaccharide, phenolic, and aliphatic domains of the intercellular adhesion-strengthening biopolymer in potato parenchyma tissue.


Subject(s)
Biocompatible Materials/chemistry , Biopolymers/chemistry , Cell Wall/metabolism , Magnetic Resonance Spectroscopy/methods , Polyesters/chemistry , Carbon/chemistry , Cell Adhesion , Flavonoids/chemistry , Phenols/chemistry , Polyphenols , Polysaccharides/chemistry , Protein Structure, Tertiary , Solanum tuberosum/metabolism
4.
Plant Physiol ; 133(1): 411-22, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12970506

ABSTRACT

Electrical potentials in cell walls (psi(Wall)) and at plasma membrane surfaces (psi(PM)) are determinants of ion activities in these phases. The psi(PM) plays a demonstrated role in ion uptake and intoxication, but a comprehensive electrostatic theory of plant-ion interactions will require further understanding of psi(Wall). psi(Wall) from potato (Solanum tuberosum) tubers and wheat (Triticum aestivum) roots was monitored in response to ionic changes by placing glass microelectrodes against cell surfaces. Cations reduced the negativity of psi(Wall) with effectiveness in the order Al(3+) > La(3+) > H(+) > Cu(2+) > Ni(2+) > Ca(2+) > Co(2+) > Cd(2+) > Mg(2+) > Zn(2+) > hexamethonium(2+) > Rb(+) > K(+) > Cs(+) > Na(+). This order resembles substantially the order of plant-root intoxicating effectiveness and indicates a role for both ion charge and size. Our measurements were combined with the few published measurements of psi(Wall), and all were considered in terms of a model composed of Donnan theory and ion binding. Measured and model-computed values for psi(Wall) were in close agreement, usually, and we consider psi(Wall) to be at least proportional to the actual Donnan potentials. psi(Wall) and psi(PM) display similar trends in their responses to ionic solutes, but ions appear to bind more strongly to plasma membrane sites than to readily accessible cell wall sites. psi(Wall) is involved in swelling and extension capabilities of the cell wall lattice and thus may play a role in pectin bonding, texture, and intercellular adhesion.


Subject(s)
Cations/pharmacology , Cell Wall/drug effects , Aluminum Chloride , Aluminum Compounds/pharmacology , Calcium Chloride/pharmacology , Cell Wall/physiology , Chlorides/pharmacology , Membrane Potentials/drug effects , Membrane Potentials/physiology , Models, Biological , Pectins/metabolism , Plant Roots/cytology , Plant Roots/physiology , Plant Tubers/cytology , Plant Tubers/physiology , Sodium Chloride/pharmacology , Solanum tuberosum/cytology , Solanum tuberosum/physiology , Triticum/cytology , Triticum/physiology
5.
Allergy ; 52(3): 323-30, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9140524

ABSTRACT

Differences in IgE binding and skin responses to pollen extracts of four species of Pistacia, and some immunochemical characteristics of this pollen were investigated. The incidence of positive SPT among atopic patients varied between 31.5% to the pollen extracts of P. vera and 24.6% to P. palaestina. The antigens are located on the exine of the grains as well as in their cytoplasm. Some of the antigens are common to all four species, whereas others seem to be specific. Cross-reactivity was found among the four species of Pistacia and between them and Schinus terebintifolious. Five conspicuous IgE-binding bands were observed in the immunoblots of the four examined species, the bands of 49, 57, 64, 68, and 79 kDa. The 36-37-kDa band of P. lentiscus and the 60- and 84-kDa bands of P. atlantica and P. vera were also noticeable. As the flowering seasons of Pistacia and Schinus do not overlap, the patients are exposed to such pollen for more than 4 months a year. Apparently, Pistacia pollen is a major source of allergy.


Subject(s)
Pollen/immunology , Binding Sites, Antibody , Blotting, Western , Humans , Immunoglobulin E/metabolism , Isoelectric Focusing , Skin Tests
6.
Harefuah ; 120(12): 716-8, 1991 Jun 16.
Article in Hebrew | MEDLINE | ID: mdl-1959807

ABSTRACT

The possibility that pollen grains of Artemisia monosperma (AM) are transported to Jerusalem from their native habitat along the coastal plain was investigated. Air-borne pollen grains were sampled in the early autumn of 1989 with a Rotorod pollen sampler. During that period only 1 of the 4 species of AM in Israel, A. monosperma, was flowering. The sampling day was typical for the late summer, with a light NW breeze. Sampling was done simultaneously in 3 sites: Tel Aviv, Carmei Yosef and Jerusalem. The greatest concentration of pollen in Tel Aviv was found during the morning hours and decreased during the course of the day. Pollen counts in Carmei Yosef reached a maximum at 11:00 a.m. A substantial number of air-borne AM pollen was recorded in Jerusalem, with a daily peak at 1:00 p.m. Such results fit well the distribution pattern of the pollen as expected from the recorded wind velocity and direction. They also agree well with the data for transportation of other air pollutants from the coastal plain to Jerusalem. Apparently AM pollen is transported to Jerusalem over distances of many tens of kilometers, even on days with light winds. Therefore, such pollen may constitute an allergenic factor in Jerusalem in the autumn. It is reasonable to assume that transportation of pollens of other coastal plants follows a similar pattern.


Subject(s)
Allergens , Pollen , Israel , Plants , Seasons , Wind
7.
Ann Allergy ; 63(5): 417-20, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2817532

ABSTRACT

Variations in the time course of flowering and in its intensity were recorded for regions in Israel along with variable climatic conditions. Such variations had an effect on pollen release into the air and on pollen counts. Two approaches for forecasting allergenic pollen dispersion were compared: (1) a survey of floral development and flowering intensity and (2) a survey of airborne pollen. There was a positive correlation between the survey of flowering and airborne pollen counts, although pollen was occasionally found after the flowering season. Further, it predicted fairly accurately the beginning of the flowering time of each species in each regio, the expected flowering duration, and intensity. Conducting a survey of flowering is a simple, easy and inexpensive operation. It is highly recommended for regions with variable climates.


Subject(s)
Air Pollution/analysis , Air Pollution/statistics & numerical data , Forecasting , Israel , Plant Development , Pollen
8.
Allerg Immunol (Paris) ; 21(8): 293-6, 1989 Oct.
Article in French | MEDLINE | ID: mdl-2803508

ABSTRACT

Israel was originally a country with desert climate and extensive agriculture. During the last 40 years, due to artificial irrigation, a rich vegetation and intensive agriculture have developed. Hayfever prevalence has risen between 1952 and 1986 from an average of 0.3% to 6.3% (with a range from 4% in the urban to 15% in the rural communities). Considering that significant (P less than 0.001) impact of pollen quantity upon hayfever incidence, an elementary pollen information system was organized (as described in the article) to help both allergists and allergic patients in their joint effort to avoid the harmful effect of a changing environment.


Subject(s)
Pollen/analysis , Rhinitis, Allergic, Seasonal/epidemiology , Agriculture , Cross-Sectional Studies , Desert Climate , Humans , Israel/epidemiology , Rhinitis, Allergic, Seasonal/etiology
9.
Clin Allergy ; 17(3): 243-9, 1987 May.
Article in English | MEDLINE | ID: mdl-3608141

ABSTRACT

Fifty-eight atopic and nine non-atopic volunteers, all residents of the Tel Aviv metropolitan area, Israel, were skin tested with extracts made from filtered pollen of Pistacia atlantica, P. lentiscus, P. palaestina and P. vera. Twenty-four out of the fifty-eight patients examined (41.4%) had positive skin reactions to at least one of the four examined species of Pistacia: seven of the patients reacted to all the examined extracts, whereas the other seventeen reacted to only some of them. Fifteen patients reacted to extracts of P. atlantica, sixteen patients reacted to extracts of P. lentiscus, ten patients reacted to extracts of P. palaestina and seven patients reacted to extracts of pollen of P. vera. None of the healthy, non-atopic volunteers reacted to any of the extracts. To the best of our knowledge, this is the first report of immunological reactions to pollen extracts of the genus Pistacia.


Subject(s)
Hypersensitivity, Immediate/immunology , Pollen/immunology , Humans , Israel , Skin Tests
10.
Ann Allergy ; 58(2): 125-7, 1987 Feb.
Article in English | MEDLINE | ID: mdl-3813129

ABSTRACT

Thirty-six atopic and eight non-atopic adult volunteers who had been exposed to ferns in their homes, were skin tested with extracts obtained from seven species of house ferns. Out of the 36 atopic patients, 18 had positive skin reactions to at least one out of seven species of the most common house ferns, whereas none of the non-atopic, healthy controls had positive reactions to any of the ferns.


Subject(s)
Hypersensitivity, Immediate/diagnosis , Pollen/immunology , Humans , Hypersensitivity, Immediate/immunology , Plants , Skin Tests , Spores
11.
J Bacteriol ; 146(3): 1067-74, 1981 Jun.
Article in English | MEDLINE | ID: mdl-6787010

ABSTRACT

Filaments of the heterocyst-forming cyanobacterium Anabaena variabilis reproduced 35SO4(2)-, incorporating 35S into cysteine, methionine, glutathione, sulfolipid, and several unidentified metabolites. The majority of the incorporated label accumulated in reduced glutathione. Heterocysts isolated from labeled filaments contained the same major labeled products. Isolated, metabolically active heterocysts were unable to reduce 35SO4(2)-, but were able to incorporate 35S2- into cysteine and glutathione. The results suggest that the initial activation of SO4(2)- occurs in vegetative cells and that some reduced forms, possibly including S20, are translocated into heterocysts.


Subject(s)
Cyanobacteria/metabolism , Sulfur/metabolism , Cysteine/metabolism , Glutathione/metabolism , Lipid Metabolism , Methionine/metabolism
12.
Oecologia ; 48(2): 244-248, 1981 Mar.
Article in English | MEDLINE | ID: mdl-28309806

ABSTRACT

Fifty-four species of the Chenopodiaceae in Israel were examined for their anatomical features, δ13C values, habitat and phytogeographical distribution. 17 species have δ13C values between -20‰ and -30‰and non-Kranz anatomy (NK) and are therefore considered as C3 plants. 37 species have δ13C values between -10‰ and -18‰ and Kranz or C4-Suaeda type anatomy and are therefore considered as C4 plants. Some C4 plants have leaf structure which seems to be intermediate between the Kranz and the C4-Suaeda type of leaf anatomy.The segregation of the species into photosynthetic groups shows tribal and phytogeographical grouping. Most of the C3 Chenopods are either mesoruderal plants or coastal halophytes, with a distribution area which covers the Euro-Siberian as well as the Mediterranean phytogeographical regions. The C4 Chenopods are mainly desert or steppe xerohalophytes with a distribution area which includes the Saharo-Arabian and/or Irano-Turanian phytogeographical regions.

13.
Plant Physiol ; 64(6): 963-5, 1979 Dec.
Article in English | MEDLINE | ID: mdl-16661114

ABSTRACT

Suaeda monoica Frossk. ex J. F. Gmel is a C(4) plant with three different photosynthesizing cell layers. The outer chlorenchymatous layer shows a high activity of phosphoenolpyruvate (PEP) carboxylase but none of ribulose bisphosphate (RuBP) carboxylase. The electrophoretic protein band of RuBP carboxylase was missing in this layer. The second chlorenchymatous cells layer shows a very high activity of RuBP carboxylase and NAD malic enzyme and only traces of activity of PEP carboxylase. The third photosynthesizing cell type is comprised of the water tissue. It has moderate activities of RuBP carboxylase and PEP carboxylase. A model for carbon flow in Suaeda monoica leaves is proposed.

14.
Plant Physiol ; 63(1): 201-5, 1979 Jan.
Article in English | MEDLINE | ID: mdl-16660679

ABSTRACT

delta(13)C values of the lichens Ramalina duriaei and Teloschistes villosus collected in their natural habitat were repeatedly measured during 2 years. Results show variations in the stable carbon isotope ratios ((13)C/(12)C). Such variations are correlated to the seasonal rainfall, i.e. low values of delta(13)C of the lichens during the winter and high values of delta(13)C during the dry summer. Relatively low delta(13)C values were obtained also in laboratory experiments with lichens grown under controlled humid conditions and in lichens collected from humid habitats.The variations in carbon isotopes were associated with quantitative metabolic changes. Under humid conditions an increase was obtained in the total amount of the extracted water-soluble fraction of the plant tissues as well as in the relative content of soluble carbohydrates.Analysis of the possible factors which may cause such variations indicates that the quantity of precipitation and the exposure time to high humidity were the main environmental factors causing seasonal variations in the delta(13)C values of the lichens. Such variations are dependent mainly on enzymic reactions and are probably less influenced by purely physicochemical processes. In view of the data presented here the balance between carboxylation and decarboxylation reactions seems to be the major factor for the observed seasonal differences. Winter accumulation of (12)C enriched components causes an over-all decrease in delta(13)C. During the summer, those storage materials are respired with concomitant increase in the delta(13)C of the residual plant material.

15.
Plant Physiol ; 56(5): 676-9, 1975 Nov.
Article in English | MEDLINE | ID: mdl-16659369

ABSTRACT

Suaeda monoica Forssk. ex J. F. Gmel was found to possess the C(4) pathway of photosynthesis. The succulent leaves of Suaeda lack a green bundle sheath formation but have a layer of chlorenchyma, containing large and centripetally arranged chloroplasts, which surrounds the water tissue. We suggest that the proximity of a chlorenchymatous cell layer to the vascular bundles is not necessary for the operation of the C(4) pathway.

SELECTION OF CITATIONS
SEARCH DETAIL
...