Consulta: subjectFacets:"Polyethylene glycol"
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Data/hora: 08/06/2024 12:30:48

Plant regeneration from protoplast of Brazilian citrus cultivars
Provedor de dados: 86
Autores: GLORIA,FERNANDA JANUZZI MENDES DA; MOURÃO FILHO,FRANCISCO DE ASSIS ALVES; MENDES,BEATRIZ MADALENA JANUZZI.
A procedure is described to regenerate plants from protoplasts of Brazilian citrus cultivars, after isolation, fusion and culture. Protoplasts were isolated from embryogenic cell suspension cultures and from leaf mesophyll of seedlings germinated in vitro. The enzyme solution for protoplast isolation was composed of mannitol (0.7 M), CaCl2 (24.5 mM), NaH2PO4 (0.92 mM), MES (6.15 mM), cellulase (Onozuka RS - Yakult, 1%), macerase (Onozuka R10 - Yakult, 1%) and pectolyase Y-23 (Seishin, 0.2%). Protoplast culture in liquid medium after chemical fusion lead to the formation of callus colonies further adapted to solid medium. Somatic embryo formation occurred spontaneously after two subcultures, on modified MT medium supplemented with 500 mg/L of malt extract....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cultivar improvement; Polyethylene glycol; Rootstock; Tissue culture.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2000000400008

Germination and tolerance of cowpea (Vigna unguiculata) cultivars to water stress
Provedor de dados: 91
Autores: Paiva,Emanoela P. de; Sá,Francisco V. da S.; Torres,Salvador B.; Brito,Marcos E. B.; Moreira,Romulo C. L.; Silva,Luderlândio de A.
ABSTRACT The objective of this study was to evaluate the tolerance of cowpea cultivars to water stress, during seed germination and seedling establishment. For this, a completely randomized experimental design was used in a factorial scheme consisting of nine cultivars of cowpea (BRS Guariba, BRS Potengi, BRS Itaim, BRS 17 Gurguéia, BRS Aracê, Paulistinha, Maratanã, Costela-de-Vaca and Canapu-Branco) and two levels of osmotic potential induced by PEG 6000 (0.0 MPa (control) and -0.4 MPa) in four replicates of 50 seeds. The variables analysed were germination, germination first count, root and shoot lengths, and dry matter accumulation of shoots and roots. The dissimilarity between the genotypes was also determined by Euclidean distance. Germination and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Initial growth; Polyethylene glycol; Osmotic potential.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000600407

Physiological quality of seed and seedling performance of crambe genotypes under water stress
Provedor de dados: 91
Autores: Machado,Fernando H. B.; David,Andréia M. S. de S.; Cangussú,Lucas V. S.; Figueiredo,Josiane C.; Amaro,Hugo T. R.
ABSTRACT Water stress is a condition that causes physiological changes in different species and even genotypes of the same species. One of the osmotic agents most used to simulate this condition is polyethylene glycol 6000. The aim of this study was to evaluate the effects of water stress on the physiological quality of seeds and performance of seedlings of crambe genotypes. A completely randomized design was used, in a factorial scheme with two genotypes (one cultivar and one line) and five osmotic potentials simulated with aqueous solutions of polyethylene glycol 6000 (control = 0, -0.25, -0.50, -1.0, -1.50 MPa), with four replicates of 50 seeds per treatment. The effects of the treatments were evaluated by means of germination, first count, germination...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Crambe abyssinica Hoechst; Germination; Polyethylene glycol.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000300175

Seed physiological quality and seedling growth of pea under water and salt stress
Provedor de dados: 91
Autores: Pereira,Isabella C.; Catão,Hugo C. R. M.; Caixeta,Franciele.
ABSTRACT The aim of this study was to evaluate seed physiological quality and initial pea (Pisum sativum) seedling development at different water and salt potentials. Polyethylene glycol 6000, sodium chloride and potassium chloride solutions with different osmotic potentials (0; -0.2; -0.4; -0.6; -0.8; -1.0, and -1.2 MPa) were used, and the experiment had a 3 × 7 factorial arrangement. The physiological quality and initial seedling growth characteristics (first germination count, final germination count, strong normal seedlings, epicotyl and taproot lengths, epicotyl dry matter, and root dry matter) were evaluated in a completely randomized experimental design, with four repetitions. Decreases in the observed variables showed that the simulated stress...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pisum sativum; Vegetable; Polyethylene glycol; Osmotic potential.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662020000200095

ผลของการทำ Osmopriming ด้วยสารเคมีต่างกันต่อการเปลี่ยนแปลงคุณภาพเมล็ดพันธุ์มะเขือเทศลูกผสม
Provedor de dados: 106
Autores: Boonmee Siri; Orranut Diumkhunthod.
The objective of this study was to investigatethe effects of osmopriming method with different chemicals on changes in quality of hybrid tomato seeds. The experiment was conducted at the Seed Quality Testing Laboratory Seed Processing Plant, Faculty of Agriculture, KhonKaen University. The tomato seeds were soaked in water plus PEG 6000 (-1.5 MPa) in combination with KNO3 (1% and 2%), KH2PO4 (1% and 2%) and vitamin C (1% and 2%) at 15°C for 5 days. After priming process, seed moisture content was subsequently reduced to their initial by therotating modified air seed dryer machine (Model KKU 40-2). Then, seed quality of primed seeds was tested quality. The results showed that primed seeds with PEG 6000 (-1.5 MPa)with vitamin C 2% had the highest germination...
Tipo: PhysicalObject
Palavras-chave: Tomato seed; Hybrid varieties; Seed priming; Seed enhancement; Accelerate aging; Seed quality; Germination percentage; Seed vigour; Osmopriming; Chemical; PEG 6000; Polyethylene glycol; Potassium nitrate; KNO3; Potassium dihydrogen phosphate; KH2PO4; Vitamin c; เมล็ดพันธุ์มะเขือเทศ; พันธุ์ลูกผสม; การเตรียมงอก; สารเคมี; การแช่เมล็ด; การเร่งอายุเมล็ดพันธุ์; การกระตุ้นการงอก; คุณภาพเมล็ดพันธุ์; อัตราการงอกของเมล็ด; ความแข็งแรงของเมล็ด.
Ano: 2013
URL: http://anchan.lib.ku.ac.th/agnet/handle/001/5730

The effects of an osmoregulator, carbohydrates and polyol on maturation and germination of ‘Golden THB’ papaya somatic embryos
Provedor de dados: 42
Autores: CHAGAS,KRISTHIANO; CIPRIANO,JAMILE L.D.; LOPES,JOSÉ CARLOS; SCHMILDT,EDILSON R.; OTONI,WAGNER C.; ALEXANDRE,RODRIGO S.
Abstract This study evaluated the effect of osmoregulators and carbohydrates on the maturation and germination of somatic embryos of papaya ‘Golden THB’. Cotyledon explants from papaya seedlings germinated in vitro on basal MS medium were cultured on somatic embryogenesis induction medium (IM) containing MS salts, myo-inositol, sucrose, agar and p-chlorophenoxyacetic acid. After 50 days, embryogenic calli were transferred onto maturation media (MM) for 45 additional days. For experiment 1, a MS-based medium supplemented with abscisic acid, activated charcoal and concentrations of PEG 6000 (0; 40; 50; 60 and 70 g L-1) was used, whereas for experiment 2 malt extract concentrations (0; 0.1; 0.2; 0.3 and 0.4 g L-1) were assessed. The normal cotyledonary...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Carica papaya L; Malt extract; Myo-inositol; Polyethylene glycol.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000703433

Somatic embryogenesis in the commercial papaya hybrid UENF/Caliman 01 relying on plantlet production from sexed adult hermaphrodite donor plants
Provedor de dados: 42
Autores: GOUVEA,DRIELLY S.; CHAGAS,KRISTHIANO; CIPRIANO,JAMILE L.D.; LOPES,JOSÉ CARLOS; SCHMILDT,EDILSON R.; OTONI,WAGNER C.; SCHMILDT,OMAR; ARAUJO,CAROLINE P. DE; ALEXANDRE,RODRIGO S.
Abstract: Somatic embryogenesis from explants from hermaphrodite papaya mother plants is an alternative for the production of true-to-type plants without the need for sexing. This study aimed to analyze hormonal and osmotic inducers in different somatic embryogenesis stages in the commercial hermaphrodite hybrid papaya UENF/Caliman 01. Leaf disks from in vitro shoots originated from ex vitro hermaphrodite plants were cultured in induction medium supplemented with different concentrations of 2,4-D (6, 9, 12, 15, and 18 μM) and 4-CPA (19, 22, 25, 28, and 31 μM). After 90 days, the formation of somatic embryos was verified. The 2,4-D induced the formation of light brown calli with low frequency (20%) of somatic embryogenesis. However, 4-CPA (25 μM) induced...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Abscisic acid; Auxins; Carica papaya L.; Gibberellic acid; Hermaphrodite explants; Polyethylene glycol.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000500856

Drying and reduction in sensitivity to desiccation of seeds of Alibertia edulis: the influence of fruit ripening stage
Provedor de dados: 42
Autores: CREMON,THAIS; DRESCH,DAIANE M.; SCALON,SILVANA P.Q.; MASETTO,TATHIANA E.
ABSTRACT The intense environmental degradation in tropical regions suitable for agriculture has decreased native forest populations of plants with important fruits and medicinal properties. Alibertia edulis is a native tree from the Brazilian Cerrado. Knowledge about the effects of drying and storage on the physiological behavior of its seeds may aid in its sustainable exploitation and conservation. The goal of the present study was to determine which fruit ripening stage results in A. edulis seeds with higher tolerance to desiccation, and to investigate the effectiveness of polyethylene glycol (PEG) induced osmotic stress in combination with abscisic acid (ABA) in increasing seed desiccation tolerance during storage. Seeds were dried in activated silica...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fast drying; Slow drying; Polyethylene glycol; Abscisic acid; Storage.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000401481

Purification of C-phycocyanin from Spirulina platensis in aqueous two-phase systems using an experimental design
Provedor de dados: 52
Autores: Antelo,Francine Silva; Costa,Jorge Alberto Vieira; Kalil,Susana Juliano.
C-phycocyanin from Spirulina platensis was purified in aqueous two-phase systems (ATPS) of polyethylene glycol (PEG)/potassium phosphate, varying the molar mass of the PEG. Results using a full factorial design showed that an increase in the concentration of salt and decrease in the concentration of PEG caused an increment in the purification factor for all the ATPS studied. Optimization of the conditions of the purification was studied using a central composite rotatable design for each molar mass of PEG. The ATPS composed of 7% (w/w) PEG 1500 or 4% (w/w) PEG 8000 (g/gmol) and 23 or 22.5% (w/w) of phosphate resulted a purification factor of 1.6-fold for C-phycocyanin, with total and 57% recovery, respectively. Process conditions were optimized for the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: C-phycocyanin; Purification Factor; Protein; Polyethylene glycol.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132015000100001

Drag reduction by polyethylene glycol in the tail arterial bed of normotensive and hypertensive rats
Provedor de dados: 56
Autores: Bessa,K.L.; Belletati,J.F.; Dos Santos,L.; Rossoni,L.V.; Ortiz,J.P.
This study was designed to evaluate the effect of drag reducer polymers (DRP) on arteries from normotensive (Wistar) and spontaneously hypertensive rats (SHR). Polyethylene glycol (PEG 4000 at 5000 ppm) was perfused in the tail arterial bed with (E+) and without endothelium (E-) from male, adult Wistar (N = 14) and SHR (N = 13) animals under basal conditions (constant flow at 2.5 mL/min). In these preparations, flow-pressure curves (1.5 to 10 mL/min) were constructed before and 1 h after PEG 4000 perfusion. Afterwards, the tail arterial bed was fixed and the internal diameters of the arteries were then measured by microscopy and drag reduction was assessed based on the values of wall shear stress (WSS) by computational simulation. In Wistar and SHR groups,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Shear stress; Flow-pressure response; Drag reduction; Endothelium; Polyethylene glycol; Hypertension.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2011000800006

Protein PEGylation for the design of biobetters: from reaction to purification processes
Provedor de dados: 60
Autores: Santos,João Henrique Picado Madalena; Torres-Obreque,Karin Mariana; Meneguetti,Giovanna Pastore; Amaro,Beatriz Panichi; Rangel-Yagui,Carlota Oliveira.
The covalent attachment of polyethylene glycol (PEG) to therapeutical proteins is an important route to develop biobetters for biomedical, biotech and pharmaceutical industries. PEG conjugation can shield antigenic epitopes of the protein, reduce degradation by proteolytic enzymes, enhance long-term stability and maintain or even improve pharmacokinetic and pharmacodynamics characteristics of the protein drug. Nonetheless, correct information in terms of the PEGylation process from reaction to downstream processing is of paramount importance for the industrial application and processing scale-up. In this review we present and discuss the main steps in protein PEGylation, namely: PEGylation reaction, separation of the products and final characterization of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: PEGylation; Biobetters; Biological drugs; Polyethylene glycol; Protein purification; Site-specific PEGylation.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502018000700408

A new methodology for polyvalent intravenous immunoglobulin solution production with a two-stage process of viral inactivation
Provedor de dados: 60
Autores: Lucena,Antônio Edson de Souza; Sampaio,Divaldo de Almeida; Silva,Ednaldo Rosas da; Paiva,Virgínia Florêncio de; Santiago,Ana Cláudia; Leite,Ana Cristina Lima.
Highly purified intravenous immunoglobulin G concentrate (IV IgG) was produced with the use of polyethylene glycol associated to a single-stage precipitation by ethanol, instead of the classic Cohn-Oncley process, which employs cold alcohol as the precipitating agent, in a three-stage process. Precipitation of crude fraction containing more than 95% of immunoglobulin G was performed by liquid chromatography with a cation exchanger, CM-Sepharose, as a stationary phase. During the process, the product was subjected to two-stage viral inactivation. The first stage was performed by the action of sodium caprylate, 30 mM at pH 5.1+/- 0.1, and the second stage was performed by the action of a solvent-detergent mixture. The finished product was formulated at 5%...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Blood derivatives; Immunoglobulins; Polyethylene glycol; Ultrafiltration; Ion exchange chromatography.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502010000400020

Effect of cellulose acetate phthalate and polyethylene glycol on physical properties and release of theophylline from microcapsules
Provedor de dados: 60
Autores: Hussain,Amjad; Mumtaz,Ahmad Mehmood; Arshad,Muhammad Sohail; Abbas,Nasir; Latif,Abida; Shamim,Rahat; Bukhari,Nadeem Irfan; Hussain,Khalid.
ABSTRACT The present study describes the development of theophylline microcapsules by a non-solvent addition method and the effect of plasticizer addition on microencapsulation. The release was studied in distilled water and the data were analysed by various mathematical models for determining the mechanism of release. Prepared microcapsules were found to be spherical, free flowing and having more than 80% entrapped drug. The polymer - cellulose acetate phthalate and plasticizer - polyethylene glycol was considered to be affecting the properties of microcapsules including drug release (time for 50% drug release, T50). The formulation with the highest proportion of polymer and without plasticizer (F3) showed the slowest release with T50 = 4.3 h, while the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Theophylline/microcapsules; Microencapsulation; Cellulose acetate phthalate; Polyethylene glycol; Microcapsules/mechanism of release; Drugs/release.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502016000100004

Physiological and cytological aspects of Inga vera subsp. affinis embryos during storage
Provedor de dados: 61
Autores: Faria,José M.R.; Davide,Lisete C.; Silva,Edvaldo A. A. da; Davide,Antonio C.; Pereira,Roselaine C.; van Lammeren,André A.M.; Hilhorst,Henk W.M.
The remarkably short storability of recalcitrant seeds has prevented their inclusion in programs of ex situ conservation. The causes of their desiccation sensitivity and rapid decline in viability during storage are not fully elucidated yet. In this study the highly recalcitrant, fully viable embryos of the tree species Inga vera subsp. affinis were stored under various conditions and analyzed physiologically and cytologically at intervals, in order to obtain more insights in their loss of viability during storage. Embryos stored fully hydrated at 5ºC fully lost viability in 18 d. Sealed storage of partially dehydrated embryos slightly prolonged their viability, with 95% germination being attained after 14 d of storage. However, after 30 d of storage,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Abscisic acid; Polyethylene glycol; Recalcitrant seeds; Seed conservation.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000400008

Seed germination and antioxidant enzyme activity in seedlings of diploid and tetraploid bahiagrass under water restriction
Provedor de dados: 65
Autores: Bortolin,Gabriel Streck; Salinas-Arcienega,Alfredo José; Galviz-Fajardo,Yutcelia Carolina; Amarante,Luciano do; Pedroso,Carlos Eduardo da Silva; Oliveira,João Carlos Pinto; Köpp,Mauricio Marini; Martins,Andrea Bicca Noguez; Tunes,Lilian Vanussa Madruga de.
ABSTRACT: The objective of the following research was to investigate the physiological responses of two bahiagrass genotypes (Paspalum notatum Flügge) submitted to water restriction, induced by polyethylene glycol (PEG6000), during seed germination. Seeds of cv. Pensacola (diploid) and Bagual ecotype (tetraploid) were placed on paper moistened with osmotic solutions at potentials of 0.0; -0.1; -0.2 and -0.3 MPa. Composed of two subsamples of 100 seeds and four experimental units per treatment, the germination test was conducted in a germination chamber under alternating temperatures of 30 °C (8 hours) and 20 °C (16 hours), with presence of light during the higher temperature. Final germination percentage and germination speed index of the seeds, as well as...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Paspalum notatum Flügge; Ecotype; Polyethylene glycol; Drought stress; Oxidative stress.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782020000500202

Tolerance of crambe (Crambe abyssinica Hochst) to salinity and water stress during seed germination and initial seedling growth
Provedor de dados: 64
Autores: Silva,Martha Freire da; Araújo,Eduardo Fontes; Silva,Laércio Junio da; Amaro,Hugo Tiago Ribeiro; Dias,Luiz Antônio dos Santos; Dias,Denise Cunha Fernandes dos Santos.
ABSTRACT Crambe is an oilseed plant whose oil is suitable for various industrial purposes, such as production of biodiesel, plastics, rubbers, and cosmetics. There are reports of the rusticity of this species and its potential for growth in arid and semi-arid environments, where water scarcity and soil salinity are common. However, studies regarding the tolerance of its seeds to these stresses and the physiological responses triggered during germination and seedling establishment under these conditions are incipient. The objective of this study was to evaluate the tolerance of crambe seeds to water deficit and salt stress during germination and early seedling development, as well as to investigate the role of antioxidant enzymes on tolerance to these...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Abiotic stresses; Antioxidant enzymes; Polyethylene glycol; Potassium chloride; Oilseed plant.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542019000100201