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PubMed2003

Irradiation D-values for Escherichia coli O157:H7 and Salmonella sp. on inoculated broccoli seeds and effects of irradiation on broccoli sprout keeping quality and seed viability.

Like alfalfa sprouts, broccoli sprouts can be a vehicle for bacterial pathogens, which can cause illness when they are consumed. The gamma irradiation process was used to reduce numbers of bacterial pathogens on broccoli sprouts and seeds, and the effect of this process on the seeds was studied. The irradiation destruct values for Salmonella sp. and for strains of Escherichia coli O157:H7 inoculated on broccoli seeds were determined. Results obtained in this study indicate that a dose of 2 kGy reduced total background counts for broccoli sprouts from 10(6) to 10(7) CFU/g to 10(4) to 10(5) CFU/g and increased the shelf life of the sprouts by 10 days. Yield ratio (wt/wt), germination percentage, sprout length, and thickness were measured to determine the effects of various irradiation doses on the broccoli seeds. Results show a decreased germination percentage at a dose level of 4 kGy, whereas the yield ratio (wt/wt), sprout length, and thickness decreased at the 2-kGy dose level. The radiation doses required to inactivate Salmonella sp. and strains of E. coli O157:H7 were higher than previously reported values. D-values, dose required for a 1-log reduction, for the nonvegetable and vegetable Salmonella sp. isolates were 0.74 and 1.10 kGy, respectively. The values for the nonvegetable and vegetable isolated strains of Escherichia coli O157:H7 were 1.43 and 1.11 kGy, respectively. With the irradiation process, a dose of up to 2 kGy can extend the shelf life of broccoli sprouts. A dose of > 2 kGy would have an adverse effect on the broccoli seed and decrease the yield of broccoli sprouts.

Brassica↗
PubMed2000

The molecular basis of the high linoleic acid content in Petunia seed oil: analysis of a seed-specific linoleic acid mutant.

From a random transposon mutagenesis experiment, using Petunia line W138, a seed-specific linoleic acid mutant was isolated. The tagged gene was cloned and identified as a microsomal Delta(12) desaturase. Expression of the gene, however, was constitutive and not, as might have been expected, seed-specific. Moreover, self-fertilized homozygous mutants still contain 40% 18:2 in the seed lipid fraction. This suggests that at least two (seed-specific) Delta(12) desaturase genes are responsible for the high linoleic acid content in Petunia seed oil. Five members of the microsomal Delta(12) desaturase gene family have been identified and isolated. Data are presented on the molecular characterization and tissue-specific expression of these genes, which suggest that, in Petunia, the flux through the prokaryotic and eukaryotic pathways of lipid synthesis might be different from the situation found in Arabidopsis.

Cloning, Molecular↗
PubMed1977

[Contamination of cotton seeds and of cotton seed cake by aflatoxin].

Following the discovery of aflatoxin M in cow's milk in the previous study, the contamination with aflatoxin of cotton-seed and cotton-seed cake which constitute the principal feed of local animals was measured. The samples were taken from 2 factories. The grain from the 1st factory was grown in the centre of the country in dry climate, and those from the 2nd source originated from the humid region of the north of Iran. The grain and cotton-seed cake from the 1st factory did not contain aflatoxin before storage. During storage the sample contamination amount and percent increased with time in both regions, with the dry less than the humid. In conclusion, Iranian cotton-seed and cotton-seed cake appear to be contaminated with aflatoxin B in 2 processes. The 1st is aflatoxin contamination before harvest, in the humid region of Iran; the 2nd is general storage aflatoxin contamination in both regions in which humidity and length of storage appear to be the principal factors.

Aflatoxins↗
PubMed1984

[Use of chigo seed (Campsiandra comosa, Benth) in human nutrition. I. Antecedents, nutritional potential, and characteristics of the plant and seed].

A review of the information in the literature in regard to the utilization of the seed of the "chigo" (Campsiandra comosa, Benth) as human food in Venezuela, is presented. The seed of the "chigo" is used as food by inhabitants in areas of the Orinoco basin. Several types of products are prepared from its flour. The nutritional potential of the seed and some of its characteristics, as well as those of the tree from which it is obtained, are also presented. Based on the carbohydrate and protein content of the seed, and on its amino acid composition, it is considered of interest to proceed with a more detailed study in order to determine its potential for human nutrition and, at the same time, analyze the processing conditions of the seed so as to increase its yield and quality as a food.

Amino Acids, Essential↗
PubMed1990

Survey of the mycoflora and mycotoxins of cotton seeds and cotton seed products in Egypt.

Thirty-nine species and 16 fungal genera were isolated from Egyptian cotton seeds, cotton seed meal and cotton seed cake on 1% glucose-Czapek's agar medium incubated at 28 degrees C. Aspergillus was the most frequent genus and it emerged in 87-100% of the samples contributing 70-98% of total fungi in the three substrates tested. The most common species were A. niger, A. flavus, A. fumigatus, A. terreus and Rhizopus stolonifer; A. niger, A. fumigatus and Penicillium corylophilum; and A. niger, A. flavus, A. terreus, A. nidulans and Rhizopus stolonifer, respectively. Cotton seeds and cotton seed products were naturally contaminated by aflatoxin B1 and B2. About 16% of the different substrates tested were positive for aflatoxin contamination. No citrinin, ochratoxin A, patulin, sterigmatocystin, diacetoxyscirpenol, T-2 toxin or zearalenone were detected in the samples assayed.

Aspergillus↗
PubMed2005

Use of seeds to control precipitation of calcium carbonate and determination of seed nature.

Understanding and controlling precipitation reactions is a major challenge for industrial crystallization. Calcium carbonate is a widely studied system: more than 3000 papers have been devoted to the subject over the past 10 years. The first step of the precipitation of calcium carbonate, from relatively concentrated solutions (0.01 mol/L), involves the formation of an initial gel phase which later transforms into calcite, vaterite, or a mixture of both phases. Our work aimed at controlling this first step. Nanosized seeds (8 nm), formed in situ, were used in order to control the often chaotic nucleation step which normally leads to poor phase selection and broad particle size distributions. Seeding has often been used to avoid spontaneous nucleation in metastable solutions for growth mechanism investigations of single-crystal calcium carbonate. Here the ability of a seeding method to control the precipitation reaction evolution even in the case of high supersaturation is demonstrated. The seeds and the presence of a polymeric additive (poly(acrylic acid)) allow the control of the precipitated polymorph and the specific surface area, while maintaining a narrow particle size distribution in the submicron range. Direct characterization methods did not succeed in identifying these nanoseeds; indirect methods using solubility calculations are used to demonstrate their existence and quantify size and number density of the nanosized seeds.

Calcium Carbonate↗
PubMed1998

A fiberless seed mutation in cotton is associated with lack of fiber cell initiation in ovule epidermis and alterations in sucrose synthase expression and carbon partitioning in developing seeds

Fiber cell initiation in the epidermal cells of cotton (Gossypium hirsutum L.) ovules represents a unique example of trichome development in higher plants. Little is known about the molecular and metabolic mechanisms controlling this process. Here we report a comparative analysis of a fiberless seed (fls) mutant (lacking fibers) and a normal (FLS) mutant to better understand the initial cytological events in fiber development and to analyze the metabolic changes that are associated with the loss of a major sink for sucrose during cellulose biosynthesis in the mutant seeds. On the day of anthesis (0 DAA), the mutant ovular epidermal cells lacked the typical bud-like projections that are seen in FLS ovules and are required for commitment to the fiber development pathway. Cell-specific gene expression analyses at 0 DAA showed that sucrose synthase (SuSy) RNA and protein were undetectable in fls ovules but were in abundant, steady-state levels in initiating fiber cells of the FLS ovules. Tissue-level analyses of developing seeds 15 to 35 DAA revealed an altered temporal pattern of SuSy expression in the mutant relative to the normal genotype. Whether the altered programming of SuSy expression is the cause or the result of the mutation is unknown. The developing seeds of the fls mutant have also shown several correlated changes that represent altered carbon partitioning in seed coats and cotyledons as compared with the FLS genotype.

Journal Article↗
PubMed1974

Proteins of Soybean Seeds: II. Accumulation of the Major Protein Components during Seed Development and Maturation.

Fresh weight and dry weight as well as quantitative and qualitative protein changes in the developing soybean (Glycine max) seed were described from 12 days after flowering until maturity. The seed proteins were separated on sucrose density gradients into three major fractions, having average sedimentation coefficients of 2.2S, 7.5S, and 11.8S. The 2.2S sedimenting proteins predominated at very early stages of development (12 days after flowering) and decreased proportionately throughout maturation. The 7.5S and 11.8S components appeared to be synthesized later in maturity and in larger amounts than the 2.2S proteins. Electrophoretic studies on extracts from whole seeds and on isolated protein fractions confirmed the early abundance of proteins in the 2.2S fraction and revealed temporal differences in the accumulation of three components of the 7.5S fraction. The 11.8S sedimenting fraction appeared throughout seed development as a homogeneous protein which accumulated in the seed with a time course similar to that of the total 7.5S protein fraction.

Journal Article↗
PubMed2002

Influence of seeding density and dynamic deformational loading on the developing structure/function relationships of chondrocyte-seeded agarose hydrogels.

Chondrocytes cultured in agarose hydrogels develop a functional extracellular matrix. Application of dynamic strain at physiologic levels to these constructs over time can increase their mechanical properties. In this study, the effect of seeding density (20 and 60 x 10(6) cells/ml) on tissue elaboration was investigated. Higher seeding densities increased tissue properties in free-swelling culture, with constructs seeded at 20 and 60 x 10(6) cells/ml reaching maximum values over the 63 day culture period of aggregate modulus HA: 43 +/- 15 kPa, Young's modulus EY: 39 +/- 3 kPa, and glycosaminglycan content [GAG]: 0.96% +/- 0.13% wet weight; and HA: 58 +/- 12 kPa, EY: 60 +/- 5 kPa, and [GAG]: 1.49% +/- 0.26% wet weight, respectively. It was further observed that the application of daily dynamic deformational loading to constructs seeded at 20 x 10(6) cells/ml enhanced biochemical content (approximately 150%) and mechanical properties (approximately threefold) compared to free-swelling controls by day 28. However, at a concentration of 60 x 10(6) cells/ml, no difference in mechanical properties was found in loaded samples versus their free-swelling controls. Multiple regression analysis showed that the mechanical properties of the tissue constructs depend more strongly on collagen content than GAG content; a finding that is more pronounced with the application of daily dynamic deformational loading. Our findings provide evidence for initial cell seeding density and nutrient accessibility as important parameters in modulating tissue development of engineered constructs, and their ability to respond to a defined mechanical stimulus.

Animals↗
PubMed2000

Dosimetric effects of needle divergence in prostate seed implant using 125I and 103Pd radioactive seeds.

In prostate seed implants, radioactive seeds are implanted into the prostate through a guiding needle with the help of a template and real-time imaging. The ideal locations of the guiding needles and the relative positions of the seeds in each needle are determined before the implantation under the assumption that the needles inserted at different locations will remain parallel. In actual implantation, the direction of the needle is subject variation. In this work, we studied how the dosimetry quality of an implant may be affected when the guiding needles deviate from its planned orientations. Needle divergence of varying degree was simulated on spherical models and actual patient implants. It was found that needle divergence degraded the dosimetric quality of an implant: The minimum target dose, the target dose coverage and therefore the tumor biological effective dose were quantitatively decreased as compared to the reference implant. The magnitude of degradation increased almost linearly with respect to the magnitude of needle divergence. For iodine-125 implants, the average reduction in minimum target dose was about 10% and 20% for needle divergence of standard deviation of 5(0) and 10(0), respectively. The dose coverage in the target was reduced by about 1% and 3% for needle divergence of standard deviation of 5(0) and 10(0), respectively. Implants designed with palladium-103 showed additional 5% reduction in minimum target dose while the effect on dose coverage was about the same as compared to the iodine-125 implants. The degree of dosimetry degradation was shown to be dependent on the size of target volume, the seed spacing used, the use of seeding margin, and on the actual configuration of needle orientations in a given implant. One needs to minimize the physical causes of needle divergence in order to minimize its impact on planned dosimetry. The study suggests that the displacement between a needle image and its planned grid point at the base of prostate should be kept less than 5 mm in order to minimize the reduction in D(min)(<5%) and the increase in cell-survival (< a factor of 10) from the planned dosimetry.

Biophysical Phenomena↗
PubMed1996

Seeding of vascular grafts with genetically modified endothelial cells. Secretion of recombinant TPA results in decreased seeded cell retention in vitro and in vivo.

BACKGROUND: Seeding of small-diameter vascular grafts with endothelial cells (ECs) genetically engineered to secrete fibrinolytic or antithrombotic proteins offers the potential to improve graft patency rates. METHODS AND RESULTS: Sheep venous ECs were transduced with a retroviral vector encoding human tissue plasminogen activator (TPA). The ECs were seeded onto 4-mm-ID synthetic (Dacron) grafts. Retention of the seeded ECs was measured 2 hours after placement of the seeded grafts both in vitro in a nonpulsatile flow system and in vivo (in sheep) as femoral and carotid interposition grafts. On exposure to flow in vitro, ECs transduced with TPA were retained at a significantly lower rate (median, 67%) than either untransduced ECs (81%) or ECs transduced with a control retroviral vector producing beta-galactosidase (beta-Gal) (80%) (P < .05 for TPA versus either control). On implantation in vivo, ECs transduced with TPA were retained at a very low rate (median, 0%), significantly less than the retention of ECs transduced with the beta-Gal vector (32%; P < .00001). Decreased in vivo retention of ECs transduced with TPA correlated modestly with increased in vitro cellular passage level (r2 = .48; P < .0001) but not with in vivo blood flow rate (P = .45). Addition of the protease inhibitor aprotinin to the cell culture and graft perfusion media resulted in a significant (P < .05) increase in in vitro retention of ECs transduced with TPA. CONCLUSIONS: Increased TPA expression significantly decreases seeded EC adherence in vitro and in vivo. Gene therapy strategies for decreasing graft thrombosis may require expression of antithrombotic molecules that lack proteolytic activity.

Animals↗
PubMedDate not supplied

Integration of enzyme-linked immunosorbent assay with conventional chromatographic procedures for quantitation of aflatoxin in individual cotton bolls, seeds, and seed sections.

Integration of an enzyme-linked immunosorbent assay (ELISA) with conventional chromatographic methods proved the versatility of ELISA as a research tool and allowed for rapid assessment of aflaxtoxin in individual cottonseeds, parts of cottonseed, and composite samples of seeds taken from individual cotton bolls. Aqueous acetone was substituted for methanol in the extraction procedure prescribed by ELISA. The substitution allowed the use of a common extract for all analytical methods. An aliquot of the extract was used to screen samples by ELISA. Negative samples were identified, and toxin levels between 1 and 70 ng/g were quantitated by ELISA. Samples with toxin levels beyond the upper limit of detection by ELISA were then subjected to more time-consuming conventional cleanup prior to quantitation by liquid chromatography (LC) or thin-layer chromatography (TLC). Toxin levels detected by LC or TLC ranged from 100 to 845,000 ng/g sample. The screen by ELISA detected large numbers of toxin-negative cotton bolls or individual seeds in minimum analysis time. The combination of techniques verified the presence of seed with no toxin adjacent to toxin-containing seed in the same lock. Toxin-negative portions of individual seed with high toxin in another portion were identified for the first time. Integration of techniques provided needed information on distribution patterns of aflatoxin in cotton so that preventive measures can be developed.

Aflatoxin B1↗
PubMed1989

A jack bean protein similar to pea seed ferritin and unrelated to concanavalin A is the only iron storage protein in jack bean seeds, although concanavalin A can form ferritin-like iron cores in vitro.

Iron storage in living organisms is performed by ferritins. These proteins are built up from 24 subunits organized in a spherical shell forming a coat to a core of bioavailable iron. Recently, it was observed that concanavalin A from jack bean can form in vitro iron cores similar to those of animal ferritins (Yariv, J., Kalb, A. J., Helliwell, J. R., Papiz, M. Z., Bauminger, E. R., and Nowik, I. (1988) J. Biol. Chem. 263, 13508-13510). From this observation and from the comparison of the three-dimensional structures of horse spleen ferritin and of the form of concanavalin A which forms soluble polynuclear iron complexes, these authors suggested that concanavalin A is the apoferritin of jack bean seeds. On the basis of immunological and biochemical results, we report here that a protein purified from jack bean seeds, unrelated to concanavalin A and similar to plant seed ferritins, is responsible for iron storage in jack bean seeds. Furthermore, concanavalin A does not contain iron in vivo. Therefore we conclude that a unique protein, ferritin, stores iron in vivo in jack bean seeds and that concanavalin A provides an unusual model for studying the formation of iron cores inside a protein shell.

Amino Acids↗
PubMed1992

Differential manifestation of seed mortality induced by seed-specific expression of the gene for diphtheria toxin A chain in Arabidopsis and tobacco.

A pea vicilin promoter-diphtheria toxin A (DTx-A) chain gene fusion was introduced into Arabidopsis and tobacco. The chimeric Dtx-A gene behaves as a dominant, seed-lethal, Mendelian factor, and the segregation ratios are consistent with the numbers of integrated copies as revealed by Southern blotting. Germination deficiency results from distinct developmental abnormalities, thus allowing genetic dissection of seed development. The endosperm is affected first in both species. In Arabidopsis, full cellularization of the initially syncytial endosperm does not take place, which results in shrinkage and a shriveled appearance of the mature dry seed. The embryo, which appears structurally normal and lacks visible lesions, ceases to develop at the partially recurved cotyledon stage and does not use the remaining endosperm. In tobacco, peripheral degeneration and premature termination of cellular endosperm development occurs at the cotyledon initiation stage. Lesions appear in the cotyledons at the advanced cotyledon stage, but the embryo continues to grow and attains nearly the same size and level of differentiation as mature wild-type embryos before degeneration and intracellular disintegration take place throughout. Accumulation of protein bodies and other cytoplasmic inclusions is very limited and occurs only in few cells. The timing and distribution of lesions follow a pattern typical for accumulation of protein bodies in wild-type seeds. These observations are consistent with expression of the vicilin promoter in the enlargement phase of cell differentiation. A novel tissue interaction arises, when the embryo uses up all the arrested endosperm: the embryo proves to be capable of absorbing the parenchyma layers of the integument, which are normally obliterated by, and incorporated into, the endosperm.(ABSTRACT TRUNCATED AT 250 WORDS)

Arabidopsis↗
PubMed1965

SEED POLYSACCHARIDES AND THEIR ROLE IN GERMINATION. A SURVEY OF THE POLYSACCHARIDE COMPONENTS OF MUSTARD SEEDS WITH SPECIAL REFERENCE TO THE EMBRYOS.

1. Methods were developed for the extraction, fractionation and purification of the more soluble polysaccharides of mustard-seed embryos. 2. One of these components was a pure homopolysaccharide, an araban, which was characterized by analysis, optical rotation, chromatography on diethylaminoethylcellulose and electrophoresis; the hydrolysis products of the methylated polysaccharide were isolated and characterized by the formation of crystalline derivatives. From these studies it emerges that mustard-seed araban is very similar to the family of pectic arabans, except that it is more highly branched than usual and contains a proportion of 1-->2-linkages. 3. A survey of the other polysaccharides of mustard seed, both in the embryos and in the seed coats, suggests a predominance of pectic-type polysaccharides.

Alkylation↗
PubMed1993

Suppression of phaseolin and lectin in seeds of common bean, Phaseolus vulgaris L.: increased accumulation of 54 kDa polypeptides is not associated with higher seed methionine concentrations.

Suppression of phaseolin and lectin accumulation in common bean resulted in higher concentrations of bean seed polypeptides with apparent molecular weights of 54 kDa and from 70 to 84 kDa on SDS-polyacrylamide gel electrophoresis. Polypeptides of 54 and 56 kDa segregated as products of different alleles. Genes for the 54/56 kDa bands and phaseolin were estimated to be 26.2 +/- 3.7 map units apart. The 54 kDa band phenotype manifested by SDS-PAGE consisted of from one to three polypeptides of 54 kDa MW on 2D gels, and the 56 kDa phenotype consisted of one polypeptide of 56 kDa plus two minor polypeptides of 54-54.5 kDa molecular weight. The pKI of these polypeptides was approximately 5.25. The methionine content of the 54 kDa polypeptides of the cultivar Great Northern Star was 1.6 +/- 0.1 g/100 g protein, which was not statistically different from the value (1.5 +/- 0.1%) obtained for phaseolin isolated by the same procedure. F2 seeds deficient for phaseolin and lectin contained as much total N per g as wild-type seeds and were not shrunken, but contained 50% more free amino acids. F2 seeds from two of the three populations contained from 8 to 13% less methionine per mg total N.

Alleles↗
PubMed1995

Studies on samh seeds (Mesembryanthemum forsskalei Hochst) growing in Saudi Arabia, 1: Anatomy of Samh seed.

The seeds of Samh (Mesembryanthemum forsskalei) are 'Ostensibly Campylatropous' as they seem externally anatropous but internally they have a curved embryo and both the seed body and the funicle exchange shapes. The embryo occupies a cylindrical seed body and is surrounded by a thin layer of endosperm; the major part of the endosperm occupies an ovoid bulge resembling a seed body.

Magnoliopsida↗
PubMed1986

[Cadmium in blue poppy seeds and poppy seed-containing products].

Blue poppy seeds, semi finished products and finished baked goods with poppy seeds, were analyzed for cadmium by atomic-absorption spectrometry. The average content was 0.739 mg/kg (median 0.654 mg/kg) for poppy seeds, 0.317 mg/kg (median 0.366 mg/kg) for semi finished products and 0.107 mg/kg (median 0.088 mg/kg) for baked goods. Poppy seeds therefore must be considered as one of the most cadmium contaminated foods. For consumers, especially children, recommendations for consumption should be established.

Cadmium↗