Comparative structural and functional analysis of genes encoding pectin methylesterases in Phytophthora spp.

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Mingora, Christina; Ewer, Jason; Ospina-Giraldo, Manuel

2014-03-15

We have scanned the Phytophthora infestans, P. ramorum, and P. sojae genomes for the presence of putative pectin methylesterase genes and conducted a sequence analysis of all gene models found. We also searched for potential regulatory motifs in the promoter region of the proposed P. infestans models, and investigated the gene expression levels throughout the course of P. infestans infection on potato plants, using in planta and detached leaf assays. We found that genes located on contiguous chromosomal regions contain similar motifs in the promoter region, indicating the possibility of a shared regulatory mechanism. Results of our investigations also suggest that, during the pathogenicity process, the expression levels of some of the analyzed genes vary considerably when compared to basal expression observed in in vitro cultures of non-sporulating mycelium. These results were observed both in planta and in detached leaf assays. Copyright © 2014 Elsevier B.V. All rights reserved.

Rapid Enzymatic Method for Pectin Methyl Esters Determination

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Lucyna Łękawska-Andrinopoulou

2013-01-01

Full Text Available Pectin is a natural polysaccharide used in food and pharma industries. Pectin degree of methylation is an important parameter having significant influence on pectin applications. A rapid, fully automated, kinetic flow method for determination of pectin methyl esters has been developed. The method is based on a lab-made analyzer using the reverse flow-injection/stopped flow principle. Methanol is released from pectin by pectin methylesterase in the first mixing coil. Enzyme working solution is injected further downstream and it is mixed with pectin/pectin methylesterase stream in the second mixing coil. Methanol is oxidized by alcohol oxidase releasing formaldehyde and hydrogen peroxide. This reaction is coupled to horse radish peroxidase catalyzed reaction, which gives the colored product 4-N-(p-benzoquinoneimine-antipyrine. Reaction rate is proportional to methanol concentration and it is followed using Ocean Optics USB 2000+ spectrophotometer. The analyzer is fully regulated by a lab written LabVIEW program. The detection limit was 1.47 mM with an analysis rate of 7 samples h−1. A paired t-test with results from manual method showed that the automated method results are equivalent to the manual method at the 95% confidence interval. The developed method is rapid and sustainable and it is the first application of flow analysis in pectin analysis.

Constitutive expression, purification and characterisation of pectin methylesterase from Aspergillus niger in Pichia pastoris for potential application in the fruit juice industry.

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Jiang, Xiuping; Chen, Peng; Yin, Maolu; Yang, Qing

2013-01-01

Pectin methylesterase (PME) catalyses the hydrolysis of the methyl ester of pectin, yielding free carboxyl groups and methanol. PME is widely used in the food, cosmetic and pharmaceutical industries. PME from Aspergillus niger was constitutively expressed to a high level in the yeast Pichia pastoris. The recombinant PME was purified by a combination of ammonium sulfate fractionation and ion exchange chromatography, giving an overall yield of 28.0%. It appeared as a single band in sodium dodecyl sulfate polyacrylamide gel electrophoresis, with a molecular mass of about 45 kDa. Optimal activity of the enzyme occurred at a temperature of 50 °C and a pH of 4.7. The K(m), V(max) and k(cat) values of the enzyme with respect to pectin were 8.6 mmol L⁻¹ [Formula: See Text], 1.376 mmol min⁻¹ mg⁻¹ and 8.26 × 10² s⁻¹ respectively. Cations such as K⁺, Mg²⁺, Ni²⁺, Mn²⁺ and Co²⁺ slightly inhibited its activity, whereas Na⁺ had no effect. PME from A. niger was constitutively expressed to a high level in P. pastoris without methanol induction. The recombinant PME was purified and characterised and shown to be a good candidate for potential application in the fruit juice industry. Copyright © 2012 Society of Chemical Industry.

New insights into heat induced structural changes of pectin methylesterase on fluorescence spectroscopy and molecular modeling basis

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Nistor, Oana Viorela; Stănciuc, Nicoleta; Aprodu, Iuliana; Botez, Elisabeta

2014-07-01

Heat-induced structural changes of Aspergillus oryzae pectin methylesterase (PME) were studied by means of fluorescence spectroscopy and molecular modeling, whereas the functional enzyme stability was monitored by inactivation studies. The fluorescence spectroscopy experiments were performed at two pH value (4.5 and 7.0). At both pH values, the phase diagrams were linear, indicating the presence of two molecular species induced by thermal treatment. A red shift of 7 nm was observed at neutral pH by increasing temperature up to 60 °C, followed by a blue shift of 4 nm at 70 °C, suggesting significant conformational rearrangements. The quenching experiments using acrylamide and iodide demonstrate a more flexible conformation of enzyme with increasing temperature, especially at neutral pH. The experimental results were complemented with atomic level observations on PME model behavior after performing molecular dynamics simulations at different temperatures. The inactivation kinetics of PME in buffer solutions was fitted using a first-order kinetics model, resulting in activation energy of 241.4 ± 7.51 kJ mol-1.

MYB52 Negatively Regulates Pectin Demethylesterification in Seed Coat Mucilage.

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Shi, Dachuan; Ren, Angyan; Tang, Xianfeng; Qi, Guang; Xu, Zongchang; Chai, Guohua; Hu, Ruibo; Zhou, Gongke; Kong, Yingzhen

2018-04-01

Pectin, which is a major component of the plant primary cell walls, is synthesized and methyl-esterified in the Golgi apparatus and then demethylesterified by pectin methylesterases (PMEs) located in the cell wall. The degree of methylesterification affects the functional properties of pectin, and thereby influences plant growth, development and defense. However, little is known about the mechanisms that regulate pectin demethylesterification. Here, we show that in Arabidopsis ( Arabidopsis thaliana ) seed coat mucilage, the absence of the MYB52 transcription factor is correlated with an increase in PME activity and a decrease in the degree of pectin methylesterification. Decreased methylesterification in the myb52 mutant is also correlated with an increase in the calcium content of the seed mucilage. Chromatin immunoprecipitation analysis and molecular genetic studies suggest that MYB52 transcriptionally activates PECTIN METHYLESTERASE INHIBITOR6 ( PMEI6 ), PMEI14 , and SUBTILISIN-LIKE SER PROTEASE1.7 ( SBT1.7 ) by binding to their promoters. PMEI6 and SBT1.7 have previously been shown to be involved in seed coat mucilage demethylesterification. Our characterization of two PMEI14 mutants suggests that PMEI14 has a role in seed coat mucilage demethylesterification, although its activity may be confined to the seed coat in contrast to PMEI6, which functions in the whole seed. Our demonstration that MYB52 negatively regulates pectin demethylesterification in seed coat mucilage, and the identification of components of the molecular network involved, provides new insight into the regulatory mechanism controlling pectin demethylesterification and increases our understanding of the transcriptional regulation network involved in seed coat mucilage formation. © 2018 American Society of Plant Biologists. All Rights Reserved.

A tale of two pectins: Diverse fine structures can result from identical processive PME treatments on similar high DM subtrates

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The effects of a processive pectin-methylesterase treatment on two different pectins, both possessing a high degree of methylesterification, were investigated. While the starting samples were purportedly very similar in fine structure, and even though the sample-averaged degree of methylesterificati...

Processive pectin methylesterases: the role of electrostatic potential, breathing motions and bond cleavage in the rectification of Brownian motions.

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Davide Mercadante

Full Text Available Pectin methylesterases (PMEs hydrolyze the methylester groups that are found on the homogalacturonan (HG chains of pectic polysaccharides in the plant cell wall. Plant and bacterial PMEs are especially interesting as the resulting de-methylesterified (carboxylated sugar residues are found to be arranged contiguously, indicating a so-called processive nature of these enzymes. Here we report the results of continuum electrostatics calculations performed along the molecular dynamics trajectory of a PME-HG-decasaccharide complex. In particular it was observed that, when the methylester groups of the decasaccharide were arranged in order to mimic the just-formed carboxylate product of de-methylesterification, a net unidirectional sliding of the model decasaccharide was subsequently observed along the enzyme's binding groove. The changes that occurred in the electrostatic binding energy and protein dynamics during this translocation provide insights into the mechanism by which the enzyme rectifies Brownian motions to achieve processivity. The free energy that drives these molecular motors is thus demonstrated to be incorporated endogenously in the methylesterified groups of the HG chains and is not supplied exogenously.

Involvement of pectin methyl-esterase during the ripening of grape berries: partial cDNA isolation, transcript expression and changes in the degree of methyl-esterification of cell wall pectins.

Science.gov (United States)

Barnavon, L; Doco, T; Terrier, N; Ageorges, A; Romieu, C; Pellerin, P

2001-11-01

Grape berries (Vitis vinifera L., cv Ugni blanc) were harvested at 12 different weeks of development in 1996 and 1997. Ripening was induced at veraison, the crucial stage of berry softening, and was followed by a rapid accumulation of glucose and fructose and an increase of pH. Total RNAs, crude proteins and cell wall material were isolated from each developmental stage. A partial length cDNA (pme1, accession number AF159122, GenBank) encoding a pectin methyl-esterase (PME, EC 3.1.1.11) was cloned by RT-PCR with degenerate primers. Northern blots revealed that mRNAs coding for PME accumulate from one week before the onset of ripening until complete maturity, indicating that this transcript represents an early marker of veraison and could be involved in berry softening. However, PME activity was detected during all developmental stages. Total activity per berry increased, whereas "specific" activity, on a fresh weight basis, decreased during development. The amount of cell wall material (per berry and per g of berry) followed the same pattern as that of PME activity (total and "specific" respectively), indicating they were tightly correlated and that PME levels varied very little in the cell walls. Nevertheless, the degree of methyl-esterification of insoluble pectins decreased throughout the development from 68% in green stages to less than 20% for the ripe berries, and this observation is consistent with the induction of PME mRNAs during ripening. Relations between transcript expression, PME activity, the DE of insoluble pectic polysaccharides and their involvement in grape berry ripening are discussed.

Molecular structural differences between low methoxy pectins induced by pectin methyl esterase II: effects on texture, release and perception of aroma in gels of similar modulus of elasticity.

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Kim, Yang; Kim, Young-Suk; Yoo, Sang-Ho; Kim, Kwang-Ok

2014-02-15

Six low-methoxy pectins with different degrees of methylesterification and amidation, and molecular weights were used to prepare gels with similar moduli of elasticity by varying the concentrations of pectin and calcium phosphate. Five aroma compounds were added to the gels and their sensory textural properties, release and perception of aromas were investigated. Sensory firmness, springiness, adhesiveness, chewiness and cohesiveness differed according to the gel type, even though the moduli of elasticity were not significantly different (ppectin exhibited the lowest release and perception for all the aroma compounds, while pectin-methylesterase-treated pectin gels exhibited relatively higher aroma release and perception. These results showed that the structural properties of pectins and gelling factors that increase the non-polar character of the gel matrices could decrease the release and perception of aromas in pectin gel systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

Genome-Wide Identification, Molecular Evolution, and Expression Profiling Analysis of Pectin Methylesterase Inhibitor Genes in Brassica campestris ssp. chinensis

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Tingting Liu

2018-05-01

Full Text Available Pectin methylesterase inhibitor genes (PMEIs are a large multigene family and play crucial roles in cell wall modifications in plant growth and development. Here, a comprehensive analysis of the PMEI gene family in Brassica campestris, an important leaf vegetable, was performed. We identified 100 Brassica campestris PMEI genes (BcPMEIs, among which 96 BcPMEIs were unevenly distributed on 10 chromosomes and nine tandem arrays containing 20 BcPMEIs were found. We also detected 80 pairs of syntenic PMEI orthologs. These findings indicated that whole-genome triplication (WGT and tandem duplication (TD were the main mechanisms accounting for the current number of BcPMEIs. In evolution, BcPMEIs were retained preferentially and biasedly, consistent with the gene balance hypothesis and two-step theory, respectively. The molecular evolution analysis of BcPMEIs manifested that they evolved through purifying selection and the divergence time is in accordance with the WGT data of B. campestris. To obtain the functional information of BcPMEIs, the expression patterns in five tissues and the cis-elements distributed in promoter regions were investigated. This work can provide a better understanding of the molecular evolution and biological function of PMEIs in B. campestris.

Combined effects of pectic enzymes on the degradation of pectin polysaccharides of banana fruit

International Nuclear Information System (INIS)

Jheng, G.; Jiang, Y.; Ghen, Y.; Yang, S.

2011-01-01

Pectin polysaccharide is one of the major components of the primary cellular wall in the middle lamella of plant tissues. The degradation of pectin polysaccharide contributes to fruit softening. In this study, water-soluble pectin (WSP) and acid-soluble pectin (ASP) were isolated from pulp tissues of banana fruit at various ripening stages, and combinations of the enzymes such as polygalcturonase (PG), pectin methylesterase (PME) and beta-galactosidase (beta-Gal) were used to investigate the effect on the degradation of WSP and ASP. PG promoted the degradation of pectin polysaccharides, especially in ASP. An enhanced effect of the degradation of WSP and ASP from various ripening banana fruit was observed in the presence of PME. In addition, beta-Gal accelerated slightly the degradation of WSP and ASP in the presence of PG. Overall, PG, PME and beta-Gal can coordinate to promote the degradation of pectin polysaccharides of banana fruit, resulting in fruit softening. (author)

Effects of membrane-filtered soy hull pectin and pre-emulsified fiber/oil on chemical and technological properties of low fat and low salt meat emulsions.

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Kim, Hyun-Wook; Lee, Yong Jae; Kim, Yuan H Brad

2016-06-01

The objectives of this study were to determine efficacy of a membrane filtration in soy hull pectin purification and evaluate combined effects of soy hull pectin and pre-emulsified fiber/oil (PE) on chemical composition and technological properties of low fat and low salt meat emulsions. Soy hull pectin was purified through two different methods (alcohol-washed (ASP) and membrane-filtered (MSP)). Insoluble soy hull residues after pectin extraction were incorporated with sunflower oil and water for the PE preparation. Meat emulsion was formulated with 58 % pork, 20 % ice, 20 % pork backfat, and 2 % NaCl as control. A total of six low fat and low salt meat emulsions (1 % NaCl and 10 % backfat) was manufactured with 1 % pectin (with/without ASP or MSP) and 10 % PE (with/without). The pectin content of ASP and MSP was 0.84 and 0.64 g L-galacturonic acid/g dry sample, respectively. The inclusion of soy hull pectin caused similar results on chemical composition, color, cooking loss, and texture of the meat emulsions, regardless of the purification method. In addition, positive impacts of the combined treatments with soy hull pectin and PE compared to single treatments on cooking loss and texture of the meat emulsions were observed. Results suggest that membrane filtration could be an effective alternative method to purify pectin, instead of alcohol-washing, and both soluble pectin and insoluble fiber from soy hulls could be used as a functional non-meat ingredient to manufacture various low fat and low salt meat products.

Restricted cell elongation in Arabidopsis hypocotyls is associated with a reduced average pectin esterification level.

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Derbyshire, Paul; McCann, Maureen C; Roberts, Keith

2007-06-17

Cell elongation is mainly limited by the extensibility of the cell wall. Dicotyledonous primary (growing) cell walls contain cellulose, xyloglucan, pectin and proteins, but little is known about how each polymer class contributes to the cell wall mechanical properties that control extensibility. We present evidence that the degree of pectin methyl-esterification (DE%) limits cell growth, and that a minimum level of about 60% DE is required for normal cell elongation in Arabidopsis hypocotyls. When the average DE% falls below this level, as in two gibberellic acid (GA) mutants ga1-3 and gai, and plants expressing pectin methyl-esterase (PME1) from Aspergillus aculeatus, then hypocotyl elongation is reduced. Low average levels of pectin DE% are associated with reduced cell elongation, implicating PMEs, the enzymes that regulate DE%, in the cell elongation process and in responses to GA. At high average DE% other components of the cell wall limit GA-induced growth.

Restricted cell elongation in Arabidopsis hypocotyls is associated with a reduced average pectin esterification level

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Derbyshire Paul

2007-06-01

Full Text Available Abstract Background Cell elongation is mainly limited by the extensibility of the cell wall. Dicotyledonous primary (growing cell walls contain cellulose, xyloglucan, pectin and proteins, but little is known about how each polymer class contributes to the cell wall mechanical properties that control extensibility. Results We present evidence that the degree of pectin methyl-esterification (DE% limits cell growth, and that a minimum level of about 60% DE is required for normal cell elongation in Arabidopsis hypocotyls. When the average DE% falls below this level, as in two gibberellic acid (GA mutants ga1-3 and gai, and plants expressing pectin methyl-esterase (PME1 from Aspergillus aculeatus, then hypocotyl elongation is reduced. Conclusion Low average levels of pectin DE% are associated with reduced cell elongation, implicating PMEs, the enzymes that regulate DE%, in the cell elongation process and in responses to GA. At high average DE% other components of the cell wall limit GA-induced growth.

Evidence for a blockwise distribution of acetyl groups onto homogalacturonans from a commercial sugar beet (Beta vulgaris) pectin.

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Ralet, Marie-Christine; Crépeau, Marie-Jeanne; Bonnin, Estelle

2008-06-01

Commercial acid-extracted sugar beet pectin was extensively hydrolysed using an endo-polygalacturonase (AnPGI from Aspergillus niger or AnPGII from A. niger or FmPG from Fusarium moniliforme) in combination with Aspergillus aculeatus pectin methyl-esterase (AaPME). The homogalacturonan-derived oligogalacturonates released were quantified by high-performance anion-exchange chromatography and their structure determined by mass spectrometry. The different endo-polygalacturonases exhibited variable tolerance towards acetyl groups. AnPGI was the most active and FmPG the less. A hypothetical homogalacturonan was constructed using the AnPGI-recovered oligogalacturonates as building blocks and the validity of the model was checked taking into account FmPG observed requirements and hydrolysis products. A blockwise repartition of the acetyl groups onto sugar beet pectin homogalacturonan is proposed.

Cell wall pectin methyl-esterification and organic acids of root tips involve in aluminum tolerance in Camellia sinensis.

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Li, Dongqin; Shu, Zaifa; Ye, Xiaoli; Zhu, Jiaojiao; Pan, Junting; Wang, Weidong; Chang, Pinpin; Cui, Chuanlei; Shen, Jiazhi; Fang, Wanping; Zhu, Xujun; Wang, Yuhua

2017-10-01

Tea plant (Camellia sinensis (O.) Kuntze) can survive from high levels of aluminum (Al) in strongly acidic soils. However, the mechanism driving its tolerance to Al, the predominant factor limiting plant growth in acid condition, is still not fully understood. Here, two-year-old rooted cuttings of C. sinensis cultivar 'Longjingchangye' were used for Al resistance experiments. We found that the tea plants grew better in the presence of 0.4 mM Al than those grew under lower concentration of Al treatments (0 and 0.1 mM) as well as higher levels treatment (2 and 4 mM), confirming that appropriate Al increased tea plant growth. Hematoxylin staining assay showed that the apical region was the main accumulator in tea plant root. Subsequently, immunolocalization of pectins in the root tip cell wall showed a rise in low-methyl-ester pectin levels and a reduction of high-methyl-ester pectin content with the increasing Al concentration of treatments. Furthermore, we observed the increased expressions of C. sinensis pectin methylesterase (CsPME) genes along with the increasing de-esterified pectin levels during response to Al treatments. Additionally, the levels of organic acids increased steadily after treatment with 0.1, 0.4 or 2 mM Al, while they dropped after treatment with 4 mM Al. The organic acids secretion from root followed a similar trend. Similarly, a gradual increase in malate dehydrogenase (MDH), citrate synthase (CS) and glycolate oxidase (GO) enzyme activities and relevant metabolic genes expression were detected after the treatment of 0.1, 0.4 or 2 mM Al, while a sharp decrease was resulted from treatment with 4 mM Al. These results confirm that both pectin methylesterases and organic acids contribute to Al tolerance in C. sinensis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

L-Altruronic acid formed by epimerization of D-galacturonic acid methyl esters during saponification of citrus pectin.

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Zhan, D; Qiu, F; Mort, A J

2001-02-15

While searching for oligosaccharides containing rhamnose residues in the endopolygalacturonase (EPG) digest of saponified citrus pectin, we found several oligomers containing, in addition to galacturonic acid, a sugar previously unreported in pectin. The 1- and 2-D 1H NMR spectra of the oligosaccharides were consistent with the sugar being a uronic acid with its 2- and 3-hydroxyls being axial and 4-hydroxyl being equatorial. MALDI-TOF mass spectrometry indicated that the oligomers consisted solely of uronic acids. Reduction of the uronic acids in the oligosaccharides converted them to galactose and altrose. The altrose was found to be the L enantiomer by comparison of its trimethylsilyl (-)-2-butyl glycosides to those of authentic D-altrose and a racemic mixture. The sugar was not found in oligosaccharides prepared from EPG digestion of citrus pectin deesterified with pectin methylesterase rather than saponification. Thus, it appears that during saponification, a small proportion of the methylesterified galacturonic acid residues in pectins is epimerized at C-5 leading to formation of L-altruronic acid residues.

Combined enzymatic and colorimetric method for determining the uronic acid and methylester content of pectin: Application to tomato products.

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Anthon, Gordon E; Barrett, Diane M

2008-09-01

A simple procedure for determining the galacturonic acid and methanol contents of soluble and insoluble pectins, relying on enzymatic pectin hydrolysis and colorimetric quantification, is described. Pectin samples are incubated with a commercial pectinase preparation, Viscozyme, then the galacturonic acid content of the hydrolyzed pectin is quantified colorimetrically using a modification of the Cu reduction procedure originally described by Avigad and Milner. This modification, substituting the commonly used Folin-Ciocalteau reagent for the arsenic containing Nelson reagent, gives a response that is linear, sensitive, and selective for uronic acids over neutral sugars. This method also avoids the use of concentrated acids needed for the commonly used m-phenylphenol method. Methanol, released by the action of the pectin methylesterase found in the Viscozyme, is quantified using alcohol oxidase and Purpald. This combined enzymatic and colorimetric procedure correctly determined the galacturonic acid and methanol content of purified, soluble citrus pectin. Application of the procedure to water insoluble pectins was evaluated with water insoluble material from apples and oranges. In both cases good agreement was obtained between this method and commonly used methods based on chemical pectin hydrolysis. Good agreement between these procedures was also found in the analysis of both soluble and insoluble pectins from several tomato products. Copyright © 2008 Elsevier Ltd. All rights reserved.

Formation and rupture of Ca(2+) induced pectin biopolymer gels.

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Basak, Rajib; Bandyopadhyay, Ranjini

2014-10-07

When calcium salts are added to an aqueous solution of polysaccharide pectin, ionic cross-links form between pectin chains, giving rise to a gel network in dilute solution. In this work, dynamic light scattering (DLS) is employed to study the microscopic dynamics of the fractal aggregates (flocs) that constitute the gels, while rheological measurements are carried out to study the process of gel rupture. As the calcium salt concentration is increased, DLS experiments reveal that the polydispersity of the flocs increase simultaneously with the characteristic relaxation times of the gel network. Above a critical salt concentration, the flocs become interlinked to form a reaction-limited fractal gel network. Rheological studies demonstrate that the limits of the linear rheological response and the critical stresses required to rupture these networks both decrease with the increase in salt concentration. These features indicate that the ion-mediated pectin gels studied here lie in a 'strong link' regime that is characterised by inter-floc links that are stronger than intra-floc links. A scaling analysis of the experimental data presented here demonstrates that the elasticities of the individual fractal flocs exhibit power-law dependences on the added salt concentration. We conclude that when both pectin and salt concentrations are increased, the number of fractal flocs of pectin increases simultaneously with the density of crosslinks, giving rise to very large values of the bulk elastic modulus.

Low temperature caused modifications in the arrangement of cell wall pectins due to changes of osmotic potential of cells of maize leaves (Zea mays L.).

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Bilska-Kos, Anna; Solecka, Danuta; Dziewulska, Aleksandra; Ochodzki, Piotr; Jończyk, Maciej; Bilski, Henryk; Sowiński, Paweł

2017-03-01

The cell wall emerged as one of the important structures in plant stress responses. To investigate the effect of cold on the cell wall properties, the content and localization of pectins and pectin methylesterase (PME) activity, were studied in two maize inbred lines characterized by different sensitivity to cold. Low temperature (14/12 °C) caused a reduction of pectin content and PME activity in leaves of chilling-sensitive maize line, especially after prolonged treatment (28 h and 7 days). Furthermore, immunocytohistological studies, using JIM5 and JIM7 antibodies, revealed a decrease of labeling of both low- and high-methylesterified pectins in this maize line. The osmotic potential, quantified by means of incipient plasmolysis was lower in several types of cells of chilling-sensitive maize line which was correlated with the accumulation of sucrose. These studies present new finding on the effect of cold stress on the cell wall properties in conjunction with changes in the osmotic potential of maize leaf cells.

Influence of UV-C irradiation on expansin and pectin-methylesterase gene expression in strawberry fruit

International Nuclear Information System (INIS)

Pombo, M.; Dotto, M.; Martinez, G.; Civello, P.

2005-01-01

Full text: The exposure to UV-C delays fruit softening, one of the main factors determining fruit post harvest life. This delay in softening may be caused by changes in the activities of enzymes and proteins involved in cell wall disassembly. Expansins are cell wall proteins involved in fruit softening, while pectin-melhylesterases (PME) are cell wall enzymes related to pectin demethylation, and their activity is affected by heating, another physical treatment based on abiotic stress. We analyzed FaPME 1 gene expression in irradiated strawberry fruits and also measured PME activity after treatment. An increase in PME activity immediately after the treatment was found. The expression of FaEXP2, FaEXP4 and FaEXP5 genes was analyzed in the same fruit samples, as well as expansin protein accumulation. For these three genes we found a decrease in expression 4 h after treatment and an increase after 24 h. The decrease in gene expression after treatment correlated with a diminution of expansins. (author)

Arabidopsis phyllotaxis is controlled by the methyl-esterification status of cell-wall pectins.

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Peaucelle, Alexis; Louvet, Romain; Johansen, Jorunn N; Höfte, Herman; Laufs, Patrick; Pelloux, Jérome; Mouille, Grégory

2008-12-23

Plant organs are produced from meristems in a characteristic pattern. This pattern, referred to as phyllotaxis, is thought to be generated by local gradients of an information molecule, auxin. Some studies propose a key role for the mechanical properties of the cell walls in the control of organ outgrowth. A major cell-wall component is the linear alpha-1-4-linked D-GalAp pectic polysaccharide homogalacturonan (HG), which plays a key role in cell-to-cell cohesion. HG is deposited in the cell wall in a highly (70%-80%) methyl-esterified form and is subsequently de-methyl-esterified by pectin methyl-esterases (PME, EC 3.1.1.11). PME activity is itself regulated by endogenous PME inhibitor (PMEI) proteins. PME action modulates cell-wall-matrix properties and plays a role in the control of cell growth. Here, we show that the formation of flower primordia in the Arabidopsis shoot apical meristem is accompanied by the de-methyl-esterification of pectic polysaccharides in the cell walls. In addition, experimental perturbation of the methyl-esterification status of pectins within the meristem dramatically alters the phyllotactic pattern. These results demonstrate that regulated de-methyl-esterification of pectins is a key event in the outgrowth of primordia and possibly also in phyllotactic patterning.

Stomatal Function Requires Pectin De-methyl-esterification of the Guard Cell Wall.

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Amsbury, Sam; Hunt, Lee; Elhaddad, Nagat; Baillie, Alice; Lundgren, Marjorie; Verhertbruggen, Yves; Scheller, Henrik V; Knox, J Paul; Fleming, Andrew J; Gray, Julie E

2016-11-07

Stomatal opening and closure depends on changes in turgor pressure acting within guard cells to alter cell shape [1]. The extent of these shape changes is limited by the mechanical properties of the cells, which will be largely dependent on the structure of the cell walls. Although it has long been observed that guard cells are anisotropic due to differential thickening and the orientation of cellulose microfibrils [2], our understanding of the composition of the cell wall that allows them to undergo repeated swelling and deflation remains surprisingly poor. Here, we show that the walls of guard cells are rich in un-esterified pectins. We identify a pectin methylesterase gene, PME6, which is highly expressed in guard cells and required for stomatal function. pme6-1 mutant guard cells have walls enriched in methyl-esterified pectin and show a decreased dynamic range in response to triggers of stomatal opening/closure, including elevated osmoticum, suggesting that abrogation of stomatal function reflects a mechanical change in the guard cell wall. Altered stomatal function leads to increased conductance and evaporative cooling, as well as decreased plant growth. The growth defect of the pme6-1 mutant is rescued by maintaining the plants in elevated CO 2 , substantiating gas exchange analyses, indicating that the mutant stomata can bestow an improved assimilation rate. Restoration of PME6 rescues guard cell wall pectin methyl-esterification status, stomatal function, and plant growth. Our results establish a link between gene expression in guard cells and their cell wall properties, with a corresponding effect on stomatal function and plant physiology. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Enzymatic gelation of sugar beet pectin in food products

DEFF Research Database (Denmark)

Bergsøe, Merete Norsker; Jensen, Mette; Adler-Nissen, Jens

2000-01-01

Sugar beet pectin is a food ingredient with specific functional properties. It may form gels by an oxidative cross-linking of ferulic acid. In the present study, the gel forming properties of three oxidative enzymes were examined in different food relevant conditions. The enzymes chosen were two...... laccases and one peroxidase. The textural properties of the produced gels were measured on a texture analyser. The influence of sugar, salt and protein were analysed. Finally, the enzymatic gelation was studied in three food products with added sugar beet pectin. These were black currant juice, milk...... and chopped heat-treated meat emulsion. The addition of salt resulted in softer, less stiff and chewy, and less adhesive gels. Generally speaking, sugar addition increased the hardness but at high concentration the gels were very brittle. However, Young's modulus was lower in gels containing sugar than...

Pectinolytic complex production by Aspergillus niger URM 4645 ...

African Journals Online (AJOL)

-PG), pectin lyase (PL), and pectin methylesterase (PE), produced by Aspergillus niger URM 4645, were studied in solid state fermentation (SSF) using yellow passion fruit peels as substrate. The effect of substrate amount, initial moisture ...

Pectin-modifying enzymes and pectin-derived materials: applications and impacts.

Science.gov (United States)

Bonnin, Estelle; Garnier, Catherine; Ralet, Marie-Christine

2014-01-01

Pectins are complex branched polysaccharides present in primary cell walls. As a distinctive feature, they contain high amount of partly methyl-esterified galacturonic acid and low amount of rhamnose and carry arabinose and galactose as major neutral sugars. Due to their structural complexity, they are modifiable by many different enzymes, including hydrolases, lyases, and esterases. Their peculiar structure is the origin of their physicochemical properties. Among others, their remarkable gelling properties make them a key additive for food industries. Pectin-degrading enzymes and -modifying enzymes may be used in a wide variety of applications to modulate pectin properties or produce pectin derivatives and oligosaccharides with functional as well as nutritional interests. This paper reviews the scientific information available on pectin structure, pectin-modifying enzymes, and the use of enzymes to produce pectin with controlled structure or pectin-derived oligosaccharides, with functional or nutritional interesting properties.

Methanol and ethanol modulate responses to danger- and microbe-associated molecular patterns

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Methanol is a byproduct of cell wall modification, released through the action of pectin methylesterases (PMEs), which demethylesterify cell wall pectins. Plant PMEs play not only a role in developmental processes but also in responses to herbivory and infection by fungal or bacterial pathogens. Mol...

Lithium ion conducting biopolymer electrolyte based on pectin doped with Lithium nitrate

Science.gov (United States)

Manjuladevi, R.; Selvin, P. Christopher; Selvasekarapandian, S.; Shilpa, R.; Moniha, V.

2018-04-01

The Biopolymer electrolyte based on pectin doped with lithium nitrate of different concentrations have been prepared by solution casting technique. The decrease in crystalline nature of the biopolymer has been identified by XRD analyses. The complex formation between the polymer and the salt has been revealed using FTIR analysis. The ionic conductivity has been explored using A.C. impedance spectroscopy which reveals that the biopolymer containing 30 wt% Pectin: 70wt%LiNO3 has highest ionic conductivity of 3.97 × 10-3 Scm-1.

Study of mango endogenous pectinases as a tool to engineer mango purée consistency.

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Jamsazzadeh Kermani, Zahra; Shpigelman, Avi; Houben, Ken; ten Geuzendam, Belinda; Van Loey, Ann M; Hendrickx, Marc E

2015-04-01

The objective of this work was to evaluate the possibility of using mango endogenous pectinases to change the viscosity of mango purée. Hereto, the structure of pectic polysaccharide and the presence of sufficiently active endogenous enzymes of ripe mango were determined. Pectin of mango flesh had a high molecular weight and was highly methoxylated. Pectin methylesterase showed a negligible activity which is related to the confirmed presence of a pectin methylesterase inhibitor. Pectin contained relatively high amounts of galactose and considerable β-galactosidase (β-Gal) activity was observed. The possibility of stimulating β-Gal activity during processing (temperature/pressure, time) was investigated. β-Gal of mango was rather temperature labile but pressure stable relatively to the temperature and pressure levels used to inactivate destructive enzymes in industry. Creating processing conditions allowing endogenous β-Gal activity did not substantially change the consistency of mango purée. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mineral absorption by albino rats as affected by some types of dietary pectins with different degrees of esterification.

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el-Zoghbi, M; Sitohy, M Z

2001-04-01

Male albino rats were fed diets contained 6.85% mineral salts for 2 weeks (adaptation condition). Then they were fed the dietary pectin administered diet for 6 weeks to evaluate the effect of administration of pectin on the absorption of some monovalent, bivalent and heavy metals in the serum of rats. The experimental parameters included, monovalent minerals (K, Na), bivalent minerals (Zn, Cu, Ca, Fe), heavy metals (Pb, Cd), serum uric acid and serum creatinine. The obtained results indicated that the serum contents of monovalent minerals were negatively affected by pectin administration. The low degree of esterification of pectin was more effective on the absorption of bivalent minerals. Also, the rat serum levels of lead and cadmium were reduced by pectin administration. Serum total proteins were reduced by pectin administration. The level of rat serum of uric acid and creatinine fed different sources of pectin were within normal levels and were insignificantly lower than that recorded for control samples.

Study of Thermal Properties, Turbidity, Effective Factors on Particle Size and Oscillatory Rheology of Pectin-Caseinate Biopolymer Nanocomplexes

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Sajedeh Bahrani

2013-02-01

Full Text Available The biopolymer-based nanocomplexes are a group of nanocapsules that are used for encapsulation and control delivery of nutraceuticals. They are formed by binding of proteins and polysaccharides. In this study, complex formation between pectin and sodium caseinate was taken place by addition of pectin solutions(0.2, 0.45 and 0.7 % w/v into the caseinate solutions (0.5, 1 and 1.5 % w/v and adjusted their pH below isoelecteric point of sodium caseinate. The effect of various factors such as biopolymer concentration, salt concentration, temperature and time of ultrasound on the properties of pectin-casein nanocomplexes was investigated. Differential scanning calorimetry (DSC and particle size analyzer were used for study of complex formation and particle size determination, respectively. The results of DSC and turbidimetry showed complex formation between the pectin and casein at pH below 5 and the results of particle size showed formation of stable dispersion with a minimum size of 86 nm at pH 4.1, caseinate of 1 % w/v and pectin 0.45 % w/v concentration. The ultrasound for more than 1 min reduced particle size and addition of salt at high and low concentrations had different effects on the stability of the colloidal system. The lowering of temperature from 21 to 4°C resulted in smaller particle size of nanocomplexes. The oscillatory rheological results showed that with increasing pectin concentration, viscoelastic moduli were increased and loss moduli were higher than storage modulus.

Structurally modified pectin for targeted lipid antioxidant capacity in linseed/sunflower oil-in-water emulsions.

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Celus, Miete; Salvia-Trujillo, Laura; Kyomugasho, Clare; Maes, Ine; Van Loey, Ann M; Grauwet, Tara; Hendrickx, Marc E

2018-02-15

The present work explored the lipid antioxidant capacity of citrus pectin addition to 5%(w/v) linseed/sunflower oil emulsions stabilized with 0.5%(w/v) Tween 80, as affected by pectin molecular characteristics. The peroxide formation in the emulsions, containing tailored pectin structures, was studied during two weeks of storage at 35°C. Low demethylesterified pectin (≤33%) exhibited a higher antioxidant capacity than high demethylesterified pectin (≥58%), probably due to its higher chelating capacity of pro-oxidative metal ions (Fe 2+ ), whereas the distribution pattern of methylesters along the pectin chain only slightly affected the antioxidant capacity. Nevertheless, pectin addition to the emulsions caused emulsion destabilization probably due to depletion or bridging effect, independent of the pectin structural characteristics. These results evidence the potential of structurally modified citrus pectin as a natural antioxidant in emulsions. However, optimal conditions for emulsion stability should be carefully selected. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optimization of continuous and intermittent microwave extraction of pectin from banana peels.

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Swamy, Gabriela John; Muthukumarappan, Kasiviswanathan

2017-04-01

Continuous and intermittent microwave-assisted extractions were used to extract pectin from banana peels. Extraction parameters which were employed in the continuous process were microwave power (300-900W), time (100-300s), pH (1-3) and in the intermittent process were microwave power (300-900W), pulse ratio (0.5-1), pH (1-3). The independent factors were optimized with the Box-Behnken response surface design (BBD) (three factor three level) with the desirability function methodology. Results indicate that the independent factors have substantial effect on the pectin yield. Optimized solutions for highest pectin yield (2.18%) from banana peels were obtained with microwave power of 900W, time 100s and pH 3.00 in the continuous method while the intermittent process yielded the highest pectin content (2.58%) at microwave power of 900W, pulse ratio of 0.5 and pH of 3.00. The optimized conditions were validated and close agreement was observed with the validation experiment and predicted value. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Structure of Pectin

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Mort, Andrew [Oklahoma State Univ., Stillwater, OK (United States). Dept. of Biochemistry and Molecular Biology

2017-01-12

At the beginning of this project we hypothesized that pectin, which is a major polysaccharide in primary plant cell walls, is composed of various distinct structural regions covalently linked together into a high molecular weight complex polymer. We also hypothesized that a considerable portion of xyloglucan, the major hemicellulose in most primary cell walls, is linked to the pectin. Our goal was to determine if these interconnections exist and to characterize the exact nature of the interactions. It seems imperative that we have a complete knowledge of the structure of pectin to be able to propose realistic models of cell walls. There is a lot of interest in the biosynthesis of pectin. I do not think it will be possible to completely understand the biosynthesis of pectin without knowing the structure of pectin and thus the sequence of reactions needed to put each sugar or ester in its correct position in the polymer. We made considerable progress in determining the detailed structure of pectin and within a year or so will be able to put forward a comprehensive model of it.

Pectin methyl esterase treatment on high-methoxy pectin for making fruit jam with reduced sugar content.

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Wang, Yuh-Tai; Lien, Ling-Lan; Chang, Ya-Chu; Wu, James Swi-Bea

2013-01-01

Pectin methyl esterase (PME) has been postulated to catalyse the transacylation reaction between pectin molecules. The present study aimed to prove the occurrence of this reaction. The feasibility of applying PME-catalysed transacylation between high-methoxy pectin molecules in making fruit jam with reduced sugar content was also investigated. PME treatment increased the turbidity and particle size in pectin solution and the molecular weight of pectin, while it decreased the number of methoxy ester linkages and the intensity of the CH₃ absorption peak in the Fourier transform infrared spectrum without changes in the number of total ester linkages in pectin molecules. These findings support the occurrence of PME-catalysed transacylation between pectin molecules. Higher values of hardness, gumminess and chewiness were found in a jam containing PME-treated citrus pectin (10 g L⁻¹) and sugar (350 g L⁻¹) as compared with either a jam containing untreated citrus pectin (10 g L⁻¹) and sugar (350 g L⁻¹) or strawberry jam containing pectin (10 g L⁻¹) from the fruit and sugar (650 g L⁻¹). The demand for sugar in jam making can be greatly reduced by the use of PME-treated high-methoxy pectin. Copyright © 2012 Society of Chemical Industry.

Textural properties of gelling system of low-methoxy pectins produced by demethoxylating reaction of pectin methyl esterase.

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Kim, Y; Yoo, Y-H; Kim, K-O; Park, J-B; Yoo, S-H

2008-06-01

After deesterification of commercial pectins with a pectin methyl esterase (PME), their gelling properties were characterized using instrumental texture analysis. The final degree of esterification (DE) of the high- and low-methoxy pectins reached approximately 6% after the PME treatment, while deesterification of low-methoxy amidated pectin stopped at 18% DE. Furthermore, DE of high-methoxy pectin was tailored to be 40%, which is equivalent to the DE of commercial low-methoxy pectin. As a result, significant changes in molecular weight (Mw) distribution were observed in the PME-treated pectins. The texture profile analysis showed that PME modification drastically increased hardness, gumminess, and chewiness, while decreasing cohesiveness and adhesiveness of the pectin gels (P pectin gel with relatively high peak molecular weight (Mp, 3.5 x 10(5)) and low DE (6), which was produced from high-methoxy pectin, exhibited the greatest hardness, gumminess, chewiness, and resilience. The hardness of low-methoxy amidated pectin increased over 300% after PME deesterification, suggesting that the effects of amide substitution could be reinforced when DE is even lower. The partial least square regression analysis indicated that the Mw and DE of the pectin molecule are the most crucial factors for hardness, chewiness, gumminess, and resilience of gel matrix.

Partition of lead in milk-pectin aqueous biphasic system with complexation agents

International Nuclear Information System (INIS)

Bartos, P.; Macasek, F.; Gerhart, P.

1997-01-01

In present work, decontamination of raw cow milk from lead was investigated using the 'membraneless dialysis'. The 4% w/w solutions of apple pectin, degree of esterification 70%, containing various complexing agents were used for experiments at the initial volume ration pectin : milk = 3:7 which changed to 8:2 at equilibration. Radioactive indicator 212 Pb was prepared from 228 Th emanator. After dissolution in Jennes-Koops buffer with 10 -5 M Pb 2+ carrier, milk was spiked with the indicator for 100 minutes. Distribution equilibrium of water and lead was achieved after next 100 minutes but yield of lead extraction into pectin phase was less then 2.3% in the case of raw milk, and less then 3.0% in the case of pasteurized milk. Due to denaturation of raw milk, there are strongly limited possibilities to influence the radionuclide partition in the systems. Various non-toxic complexation agents (glycine, alanine, histidine, cysteine, Edtacal) were applied to improve extraction of lead to pectin phase. Glycine and histidine have not influence on lead extraction yields but there was observed an increased yield, 3,8% for alanine and even 25% for 0.002 M cysteine. As the most interesting appeared application of Edtacal, calcium salt of ethylenediaminetetraacetic acid, EDTA by which the recovery of lead with with pectin phase reached about 80% at concentration of EDTA in initial pectin phase 0.001 M. The retention of Pb 2+ cation in milk phase is extraordinary high as compared with strontium and corresponds to behavior of trivalent ions what is attributed to specific interactions with thiol groups of milk components

Pectin methylesterase activity determined by different methods and thermal inactivation of exogenous pme in mango juice Determinação da atividade da pectina metilesterase por diferentes métodos e inativação térmica da PME exógena no suco de manga

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Samantha Lemke Gonzalez

2011-10-01

Full Text Available Pectin methylesterase (PME hydrolyzes methyl ester groups in pectin chains to form carboxylic groups, releasing methanol and H3O+. The aim of this study was to determine PME activity in samples of pectinases by UV-VIS spectroscopy, to measure the acid and methanol produced in the reaction of pectin with pectinase and to verify the thermal inactivation of exogenous PME in mango juice. The activity of PME in samples of pectinase was determined by potentiometry, UV-VIS spectroscopy, and by the action of alcohol oxidase. The reaction showed greater activity at pH 4.0 to 4.5 and at a temperature of 45° C. PME activity determined by UV-VIS spectroscopy with bromophenol blue indicator showed a good correlation with the activity determined by potentiometry and with alcohol oxidase. The results showed that bromophenol blue indicators can be used to determine PME activity in samples of pectinases where the optimum pH is located in the acidic range. The thermal inactivation of exogenous PME in mango juice occurred at 75° C for 20 min of exposure.A PME hidrolisa os grupos metil éster na cadeia da pectina, formando grupos carboxílicos, liberando metanol e H3O+. Objetivou-se, com o presente estudo, determinar a atividade da PME em amostras de pectinases por espectroscopia Uv-vis para quantificar o ácido e o metanol produzido na reação da pectina com as pectinases e verificar a inativação térmica da PME exógena no suco de manga. A atividade da PME nas três amostras de pectinases foi determinada por potenciometria, espectroscopia Uv-Vis, e pela ação da álcool oxidase. A reação mostrou uma maior atividade em H de 4,0 a 4,5 e a temperatura de 45º C. A atividade da PME, determinada por UV-Vis com o indicador azul de bromofenol apresentou uma boa correlação com a atividade determinada por potenciometria e com a álcool oxidase. Os resultados mostraram que o indicador azul de bromofenol pode ser utilizado para determinar a atividade da PME em

Factors affecting methanol content of fermented plant beverage ...

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TrueFasterUser

2013-07-03

ANZFA) permitted the maximum concentration of methanol in spirit beverages at 8 g/L of ..... German Federal Republic Patent. DE 43 (13)549. Frenkel C, Peters JS, Tieman DM, Tiznado ME, Handa AK (1998). Pectin Methylesterase ...

Isolation, characterization and modification of citrus pectins

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MARIA KRATCHANOVA

2012-01-01

Full Text Available Orange and lemon peels were used for obtaining pectic polysaccharides. Citrus peels were previously treated with 96% ethanol, and the obtained alcohol-insoluble solids (AIS were subjected to a sequential extraction with hot distilled water and hot 0.5% HCl. Water- and acid-extracted orange (WEOP and AEOP and lemon (WELP and AELP pectins were obtained. Acid extraction gave higher yields of pectin than water extraction and lemon peels were richer in pectin. Comparative investigations were carried out with chromatographically purified commercial citrus pectin (CPCP. Chemical and physicochemical characterization of all pectins was accomplished. It was found that pectins were similar in anhydrouronic acid content (AUАC, 69-81%, but differed in their degree of methylesterification (DM, 55-81%. Generally water-extracted pectins were with higher DM. Both orange pectins were with higher DM and degree of acetylation (DA, 2%, in comparison with the corresponding lemon pectins. Water-extracted pectins were with higher degree of feruloylation (DF, 0.12-0.34%. To our knowledge this is the first report on the estimation of ester-linked ferulic acid in orange and lemon peel pectins. Pectic polysaccharides differed in molecular weight and homogeneity. WELP was with the highest molecular weight and homogeneity. The pectins contained D-galacturonic and D-glucuronic acids, L-arabinose, D-galactose, L-fucose, L-rhamnose and D-xylose. All investigated pectins showed immunostimulating activity by complement activation in the classical pathway at 1.25 and 2.5 mg/mL. Pectic polysaccharides were modified with endopolygalacturonase. Enzyme-modified CPCP and WEOP had higher anti-complementary activity than the corresponding initial pectins.

Overexpression of a tea flavanone 3-hydroxylase gene confers tolerance to salt stress and Alternaria solani in transgenic tobacco.

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Mahajan, Monika; Yadav, Sudesh Kumar

2014-08-01

Flavan-3-ols are the major flavonoids present in tea (Camellia sinensis) leaves. These are known to have antioxidant and free radical scavenging properties in vitro. Flavanone 3-hydroxylase is considered to be an important enzyme of flavonoid pathway leading to accumulation of flavan-3-ols in tea. Expression analysis revealed the upregulation in transcript levels of C. sinensis flavanone 3-hydroxylase (CsF3H) encoding gene under salt stress. In this study, the biotechnological potential of CsF3H was evaluated by gene overexpression in tobacco (Nicotiana tabacum cv. Xanthi). Overexpression of CsF3H cDNA increased the content of flavan-3-ols in tobacco and conferred tolerance to salt stress and fungus Alternaria solani infection. Transgenic tobaccos were observed for increase in primary root length, number of lateral roots, chlorophyll content, antioxidant enzyme expression and their activities. Also, they showed lesser malondialdehyde content and electrolyte leakage compared to control tobacco plants. Further, transgenic plants produced higher degree of pectin methyl esterification via decreasing pectin methyl esterase (PME) activity in roots and leaves under unstressed and salt stressed conditions. The effect of flavan-3-ols on pectin methyl esterification under salt stressed conditions was further validated through in vitro experiments in which non-transgenic (wild) tobacco seedlings were exposed to salt stress in presence of flavan-3-ols, epicatechin and epigallocatechin. The in vitro exposed seedlings showed similar trend of increase in pectin methyl esterification through decreasing PME activity as observed in CsF3H transgenic lines. Taken together, overexpression of CsF3H provided tolerance to salt stress and fungus A. solani infection to transgenic tobacco through improved antioxidant system and enhanced pectin methyl esterification.

Pectin methyl esterases and pectins in normal and hyperhydric shoots of carnation cultured in vitro.

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Saher, Shady; Piqueras, Abel; Hellin, Eladio; Olmos, Enrique

2005-02-01

Control and hyperhydric micropropagated plantlets from three carnation cultivars have been used to study their pectin composition and the activity of pectin methyl esterases (PMEs; EC 3.1.1.11). Pectins are a highly heterogeneous group of polymers that contribute to cell adhesion, cell wall architecture, and cell wall mechanical strength. Pectins control cell wall porosity and cell wall ionic status and are implicated in intercellular space development. The degree of esterification of pectins is controlled by the activity of cell wall PMEs; their different actions can affect the properties of the cell wall, which have been considered important with respect to controlling the development of hyperhydricity. The total pectins of hyperhydric leaves of the three varieties were significantly reduced in comparison with controls. The pectate fraction was significantly increased in hyperhydric leaves of all varieties while soluble pectins and protopectins were significantly lower. The PME activity of hyperhydric leaves was higher (4-10 times) compared to controls of the three varieties. Isoelectric focusing of PME isozymes revealed the presence of three isoforms; neutral PME activity was the major isozyme in control and hyperhydric leaves of the three varieties, whilst a decrease in the activity of the acidic isoforms was observed in hyperhydric leaves. The different PME activities could regulate some of the structural changes related to hyperhydricity in micropropagated carnation plants.

Infrared Fourier spectres of pectin obtained from pumpkin

International Nuclear Information System (INIS)

Usmanova, S.R.; Dzhonmurodov, A.S.; Nazirova, Kh.I.; Mukhidinov, Z.K.

2015-01-01

Present article is devoted to infrared Fourier spectres of pectin obtained from pumpkin. The analysis of pectin obtained from pumpkin was conducted by means of infrared spectrophotometer with Fourier transformation. The infrared spectroscopic study of pectin polysaccharide fraction of pectin matter, as well as pectin helium and micro helium obtained by means of fast extraction was conducted.

Structural characteristics of pumpkin pectin extracted by microwave heating.

Science.gov (United States)

Yoo, Sang-Ho; Lee, Byeong-Hoo; Lee, Heungsook; Lee, Suyong; Bae, In Young; Lee, Hyeon Gyu; Fishman, Marshall L; Chau, Hoa K; Savary, Brett J; Hotchkiss, Arland T

2012-11-01

To improve extraction yield of pumpkin pectin, microwave heating was adopted in this study. Using hot acid extraction, pumpkin pectin yield decreased from 5.7% to 1.0% as pH increased from pH 1.0 to 2.0. At pH 2.5, no pectin was recovered from pumpkin flesh powder. After a pretreatment at pH 1.0 and 25 °C for 1 h, pumpkin powder was microwave-extracted at 120 °C for 3 min resulting in 10.5% of pectin yield. However, premicrowave treatment at 60 °C for 20 min did not improve extraction yield. When microwave heating at 80 °C for 10 min was applied after premicrowave treatment, final pectin yield increased to 11.3%. When pH was adjusted to 2.0, the yield dropped to 7.7% under the same extraction conditions. Molecular shape and properties as well as chemical composition of pumpkin pectin were significantly affected depending on extraction methods. Galacturonic acid content (51% to 58%) of pumpkin pectin was lower than that detected in commercial acid-extracted citrus pectin, while higher content of neutral sugars and acetyl esters existed in pumpkin pectin structure. Molecular weight (M(w) ) and intrinsic viscosity (η(w) ) determined for microwave-extracted pumpkin pectins were substantially lower than acid-extracted pectin, whereas polydispersity was greater. However, microwave-extracted pectin at pH 2.0 had more than 5 times greater M(w) than did the pectin extracted at pH 1.0. The η(w) of microwave-extracted pectin produced at pH 2.0 was almost twice that of other microwave-extracted pectins, which were comparable to that of acid-extracted pectin. These results indicate that extraction yield of pumpkin pectin would be improved by microwave extraction and different pectin structure and properties can be obtained compared to acid extraction. Pumpkin is a promising alternative source for pectin material. Pumpkin pectin has a unique chemical structure and physical properties, presumably providing different functional properties compared to conventional commercial

The ectopic expression of a pectin methyl esterase inhibitor increases pectin methyl esterification and limits fungal diseases in wheat.

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Volpi, Chiara; Janni, Michela; Lionetti, Vincenzo; Bellincampi, Daniela; Favaron, Francesco; D'Ovidio, Renato

2011-09-01

Cell wall pectin methyl esterification can influence plant resistance because highly methyl-esterified pectin can be less susceptible to the hydrolysis by pectic enzymes such as fungal endopolygalacturonases (PG). Pectin is secreted into the cell wall in a highly methyl-esterified form and, here, is de-methyl esterified by pectin methyl esterase (PME). The activity of PME is controlled by specific protein inhibitors called PMEI; consequently, an increased inhibition of PME by PMEI might modify the pectin methyl esterification. In order to test the possibility of improving wheat resistance by modifying the methyl esterification of pectin cell wall, we have produced durum wheat transgenic lines expressing the PMEI from Actinidia chinensis (AcPMEI). The expression of AcPMEI endows wheat with a reduced endogenous PME activity, and transgenic lines expressing a high level of the inhibitor showed a significant increase in the degree of methyl esterification. These lines showed a significant reduction of disease symptoms caused by the fungal pathogens Bipolaris sorokiniana or Fusarium graminearum. This increased resistance was related to the impaired ability of these fungal pathogens to grow on methyl-esterified pectin and to a reduced activity of the fungal PG to hydrolyze methyl-esterified pectin. In addition to their importance for wheat improvement, these results highlight the primary role of pectin despite its low content in the wheat cell wall.

Structural characterization of native high-methoxylated pectin using nuclear magnetic resonance spectroscopy and ultraviolet matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Comparative use of 2,5-dihydroxybenzoic acid and nor-harmane as UV-MALDI matrices.

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Monge, María Eugenia; Negri, R Martín; Kolender, Adriana A; Erra-Balsells, Rosa

2007-01-01

The successful analysis by ultraviolet matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (UV-MALDI-TOF MS) of native and hydrolyzed high-methoxylated pectin samples is described. In order to find the optimal conditions for UV-MALDI-TOF MS analysis several experimental variables were studied such as: different UV-MALDI matrices (nor-harmane, 2,5-dihydroxybenzoic acid), sample preparation methods (mixture, sandwich), inorganic salt addition (doping salts, NaCl, KCl, NH(4)Cl), ion mode (positive, negative), linear and reflectron mode, etc. nor-Harmane has never been used as a UV-MALDI matrix for the analysis of pectins but its use avoids pre-treatment of the sample, such as an enzymatic digestion or an acid hydrolysis, and there is no need to add salts, making the analysis easier and faster. This study suggested an alternative way of analyzing native high-methoxylated pectins, with UV-MALDI-TOF MS, by using nor-harmane as the matrix in negative ion mode. The analysis by (1)H and (13)C nuclear magnetic resonance (NMR) spectroscopy of the native and hydrolyzed pectin is also briefly described. Copyright (c) 2007 John Wiley & Sons, Ltd.

Pectin/anhydrous dibasic calcium phosphate matrix tablets for in vitro controlled release of water-soluble drug.

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Mamani, Pseidy Luz; Ruiz-Caro, Roberto; Veiga, María Dolores

2015-10-15

Different pectin/anhydrous dibasic calcium phosphate (ADCP) matrix tablets have been developed in order to obtain controlled release of a water-soluble drug (theophylline). Swelling, buoyancy and dissolution studies have been carried out in different aqueous media (demineralized water, progressive pH medium, simulated gastric fluid, simulated intestinal fluid and simulated colonic fluid), to characterize the matrix tablets. When the pectin/ADCP ratio was ≥0.26 (P1, P2, P3 and P4 tablets) a continuous swelling and low theophylline dissolution rate from the matrices were observed. So, pectin gel forming feature predominated over the ADCP properties, yielding pH-independent drug release behavior from these matrices. On the contrary, pectin/ADCP ratios ≤0.11 (P5 and P6 tablets) allowed to achieve drug dissolution pH dependent. Consequently, the suitable selection of the pectin/ADCP ratio will allow to tailor matrix tablets for controlled release of water-soluble drugs in a specific manner in the gastrointestinal tract. Copyright © 2015 Elsevier B.V. All rights reserved.

Purification and Characterization of a Unique Pectin Lyase from Aspergillus giganteus Able to Release Unsaturated Monogalacturonate during Pectin Degradation

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Danielle Biscaro Pedrolli

2014-01-01

Full Text Available A pectin lyase, named PLIII, was purified to homogeneity from the culture filtrate of Aspergillus giganteus grown in submerged culture containing orange peel waste as carbon source. PLIII was able to digest apple pectin and citrus pectins with different degrees of methyl esterification. Interestingly, the PLIII activity was stimulated in the presence of some divalent cations including Pb2+ and was not significantly affected by Hg2+. Like other pectin lyases, PLIII is stimulated by but is not dependent on Ca2+. The main soluble product released during the degradation of pectic substances promoted by the PLIII is compatible with an unsaturated monogalacturonate. PLIII is a unique enzyme able to release unsaturated monogalacturonate as the only soluble product during the degradation of pectic substances; therefore, PLIII was classified as an exo-pectin lyase. To our knowledge, this is the first characterization of an exo-pectin lyase. The PLIII described in this work is potentially useful for ethanol production from pectin-rich biomass, besides other common applications for alkaline pectinases like preparation of textile fibers, coffee and tea fermentation, vegetable oil extraction, and the treatment of pulp in papermaking.

[The use of pectin-containing enterosorbents in exposure to radionuclides and heavy metals].

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Trakhtenberg, I M; Litenko, V A; Dereviago, I B; Demchenko, P I; Mikhaĭlovskiĭ, S V

1992-05-01

The pectin-vitamin composition (PVC) and its complex with active carbon (AC) was investigated for use as an oral sorbent to protect radionuclide (Sr-85, Cs-137) accumulation. PVC is composed of the natural mixture of cellulose, pectin (Ca-salt), flavonoides, vitamins of the B-group, PP and C. Investigation of PVC radioprotective action was carried out on the two groups of rats (n = 30) which received 1306 Bk/animal of Sr-85 or 343 Bk/animal of Cs-137 daily. One of the group of rats received every day also 300 mg of PVC. After 30 days level of Sr-85 was less by 56.6%, level of Cs = 137 was less by 27.6% in PVC-treated than in the control group (P < 0.05). Composite sorbent consisting of PVC and AC was slightly less effective in removing of Sr and Cs.

Thiolated pectin-doxorubicin conjugates: Synthesis, characterization and anticancer activity studies.

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Cheewatanakornkool, Kamonrak; Niratisai, Sathit; Manchun, Somkamol; Dass, Crispin R; Sriamornsak, Pornsak

2017-10-15

In this paper, pectin was cross-linked by a coupling reaction with either thioglycolic acid or cystamine dihydrochloride to form thiolated pectins. The thiolated pectins were then coupled with doxorubicin (DOX) derivative to obtain thiolated pectin-DOX conjugates by two different methods, disulfide bond formation and disulfide bond exchange. The disulfide bond exchange method provided a simple, fast, and efficient approach for synthesis of thiolated pectin-DOX conjugates, compared to the disulfide bond formation. Characteristics, physicochemical properties, and morphology of thiolated pectins and thiolated pectin-DOX conjugates were determined. DOX content in thiolated pectin-DOX conjugates using low methoxy pectin was found to be higher than that using high methoxy pectin. The in vitro anticancer activity of thiolated pectin-DOX conjugates was significantly higher than that of free DOX, in mouse colon carcinoma and human bone osteosarcoma cells, but insignificantly different from that of free DOX, in human prostate cancer cells. Due to their promising anticancer activity in mouse colon carcinoma cells, the thiolated pectin-DOX conjugates might be suitable for building drug platform for colorectal cancer-targeted delivery of DOX. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental design applied to the optimization and partial ...

African Journals Online (AJOL)

The objective of this work was to optimize the medium composition for maximum pectin-methylesterase (PME) production from a newly isolated strain of Penicillium brasilianum by submerged fermentation. A Plackett-Burman design was first used for the screening of most important factors, followed by a 23 full ...

А new factor effecting gel strength of pectin polysaccharides

Directory of Open Access Journals (Sweden)

S. E. Kholov

2016-01-01

Full Text Available Pectin polysaccharides obtained from various raw materials have a different component composition and form gels with water, sugar and acid or calcium. In this study, an experimental approach the gelation properties of different pectin samples, varied from different sources, using new methods of hydrolysis and purification. Samples were obtained by hydrolysis of accelerated extraction of pectin and purified by diaultrfiltration, have a high gel strength. The highest gel strength have been found in series of high methoxyl (HM- pectin samples of apple, peach, orange and low methoxyl (LM- pectin samples of commercial citrus pectin and apple pectin obtained by new method. It is shown that in addition to the basic parameters (the content of galacturonic acid, degree of esterification, molecular weight and hidrodinamic radius macromolecule to affect gel strength pectins aggregation of macromolecules, which is determined by the z-average molecular weight. There were observed a clear pattern of the influence of the molecular weight on hydrodynamic parameters for both HM- and LM- pectin samples on the gel strength. It were shown that a high values of molecular weight, intrinsic viscosity, and radius of gyration of pectin samples can significantly increase gel strength, while the value of Mz oppositely influenced the gel strength. As a result, a systematic analysis of this parameter and its relationship to the average molecular weight found that indeed the ratio Mz/Mw for pectin’s is an crucial to assess the quality of pectin at the study of gel strength for pectin polysaccharides.

Determination of pectin content of eucalyptus wood

NARCIS (Netherlands)

Coetzee, B.; Schols, H.A.; Wolfaardt, F.

2011-01-01

Very little is known about the occurrence of pectin in wood and it is speculated that between 10 mg g-1 and 40 mg g-1 of wood consists of pectin. The present study aimed to quantify pectin in eucalyptus wood and to determine the influence of tree species, yield potential of the site, tree age class

Potato tuber pectin structure is influenced by pectin methyl esterase activity and impacts on cooked potato texture.

Science.gov (United States)

Ross, Heather A; Wright, Kathryn M; McDougall, Gordon J; Roberts, Alison G; Chapman, Sean N; Morris, Wayne L; Hancock, Robert D; Stewart, Derek; Tucker, Gregory A; James, Euan K; Taylor, Mark A

2011-01-01

Although cooked potato tuber texture is an important trait that influences consumer preference, a detailed understanding of tuber textural properties at the molecular level is lacking. Previous work has identified tuber pectin methyl esterase activity (PME) as a potential factor impacting on textural properties. In this study, tuber PME isoform and gene expression profiles have been determined in potato germplasm with differing textural properties as assessed using an amended wedge fracture method and a sloughing assay, revealing major differences between the potato types. Differences in pectin structure between potato types with different textural properties were revealed using monoclonal antibodies specific for different pectic epitopes. Chemical analysis of tuber pectin clearly demonstrated that, in tubers containing a higher level of total PME activity, there was a reduced degree of methylation of cell wall pectin and consistently higher peak force and work done values during the fracture of cooked tuber samples, demonstrating the link between PME activity, the degree of methylation of cell wall pectin, and cooked tuber textural properties.

Microwave-assisted extraction of pectin from cocoa peel

Science.gov (United States)

Sarah, M.; Hanum, F.; Rizky, M.; Hisham, M. F.

2018-02-01

Pectin is a polymer of d-galacturonate acids linked by β-1,4 glycosidic bond. This study isolates pectin from cocoa peel (Theobroma cacao) using citric acid as solvent by microwave-assisted extraction method. Cocoa peels (moisture content of 10%) with citric acid solution (pH of 1.5) irradiated by microwave energy at various microwave power (180, 300, 450 and 600 W) for 10, 15, 20, 25 and 30 minutes respectively. Pectin obtained from this study was collected and filtrated by adding 96% ethanol to precipitate the pectin. The best results obtained from extraction process using microwave power of 180 Watt for 30 minutes. This combination of power and time yielded 42.3% pectin with moisture content, ash content, weight equivalent, methoxyl content and galacturonate levels were 8.08%, 5%, 833.33 mg, 6.51% and 58,08%, respectively. The result finding suggested that microwave-assisted extraction method has a great potency on the commercial pectin production.

Effect of different pectin on bile acid biosynthesis

International Nuclear Information System (INIS)

Khalikova, M.D.; Mukhiddinov, Z.K.; Nuraliev, Yu.N.; Khaydarov, K.Kh.

2009-01-01

The objective of the study was to examine the effects of consumption of different pectins from peach, quince, and apricot on bile flow and bile secretion of bile acids, cholesterol, phospholipids and bilirubin in rats. Six groups of nine rats were fed diets containing pectin 20 mg/kg once a day for two weeks. These groups of rats were compared with the group fed on physiological solution as a control and two groups fed on flamenol. Results of our study indicate that pectins, by decreasing cholesterol levels and enhancing bile acid secretion may cause increased hepatic synthesis of bile acids, phospholipids and reduced bilirubin synthesis. Among the studied pectins the apricot pectin shows in a very consistent lowering of cholesterol and bilirubin levels

Pectin: cell biology and prospects for functional analysis.

Science.gov (United States)

Willats, W G; McCartney, L; Mackie, W; Knox, J P

2001-09-01

Pectin is a major component of primary cell walls of all land plants and encompasses a range of galacturonic acid-rich polysaccharides. Three major pectic polysaccharides (homogalacturonan, rhamnogalacturonan-I and rhamnogalacturonan-II) are thought to occur in all primary cell walls. This review surveys what is known about the structure and function of these pectin domains. The high degree of structural complexity and heterogeneity of the pectic matrix is produced both during biosynthesis in the endomembrane system and as a result of the action of an array of wall-based pectin-modifying enzymes. Recent developments in analytical techniques and in the generation of anti-pectin probes have begun to place the structural complexity of pectin in cell biological and developmental contexts. The in muro de-methyl-esterification of homogalacturonan by pectin methyl esterases is emerging as a key process for the local modulation of matrix properties. Rhamnogalacturonan-I comprises a highly diverse population of spatially and developmentally regulated polymers, whereas rhamnogalacturonan-II appears to be a highly conserved and stable pectic domain. Current knowledge of biosynthetic enzymes, plant and microbial pectinases and the interactions of pectin with other cell wall components and the impact of molecular genetic approaches are reviewed in terms of the functional analysis of pectic polysaccharides in plant growth and development.

Radiation sensitivity of different citric pectins

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Inamura, Patricia Y.; Mastro, Nelida L. del [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: patyoko@yahoo.com; nlmastro@ipen.br

2007-07-01

Pectic substances are important soluble polysaccharides of plant origin of considerable interest for food industry as gelling agent and stabilizer in jams, fruit jellies, yogurt drinks and lactic acid beverages. Polysaccharides can be degraded by ionizing radiation due to the free radical induced scission of the glycosidic bonds. Viscosity methods had been used to determine the efficiency of hydroxyl radical induced chain breaks generation in macromolecules. In the present work samples of pectin with different degree of methoxylation were employed in order to study their radiation sensitivity by means of viscosity measurements. Samples of citric pectin 1% solutions were irradiated with gamma rays at different doses, ranging from 0 to 15 kGy, using a {sup 60}Co Gammacell 220 (AECL), dose rate about 2 kGy/h. After irradiation the viscosity was measured on the viscometer Brookfield model LV-DVIII at 50, 60 and 70 deg C within a period of 48h. Pectin viscosity with high degree of methoxylation decreased sharply with the radiation dose remaining almost constant from 10 kGy. Pectin with low degree of methoxylation presented initially higher values of viscosity and the radiation induced decrease was also pronounced. Viscosity measurements decreased with the increase of the temperature applied for both kind of samples. The effect of radiation induced chain breaks generation in pectin molecules was evident through the viscosity reduction of irradiated pectin solutions although the viscosity presented diverse values depending of the degree of methoxylation of carboxyl groups in the backbone of polysaccharide macromolecules. (author)

Radiation sensitivity of different citric pectins

International Nuclear Information System (INIS)

Inamura, Patricia Y.; Mastro, Nelida L. del

2007-01-01

Pectic substances are important soluble polysaccharides of plant origin of considerable interest for food industry as gelling agent and stabilizer in jams, fruit jellies, yogurt drinks and lactic acid beverages. Polysaccharides can be degraded by ionizing radiation due to the free radical induced scission of the glycosidic bonds. Viscosity methods had been used to determine the efficiency of hydroxyl radical induced chain breaks generation in macromolecules. In the present work samples of pectin with different degree of methoxylation were employed in order to study their radiation sensitivity by means of viscosity measurements. Samples of citric pectin 1% solutions were irradiated with gamma rays at different doses, ranging from 0 to 15 kGy, using a 60 Co Gammacell 220 (AECL), dose rate about 2 kGy/h. After irradiation the viscosity was measured on the viscometer Brookfield model LV-DVIII at 50, 60 and 70 deg C within a period of 48h. Pectin viscosity with high degree of methoxylation decreased sharply with the radiation dose remaining almost constant from 10 kGy. Pectin with low degree of methoxylation presented initially higher values of viscosity and the radiation induced decrease was also pronounced. Viscosity measurements decreased with the increase of the temperature applied for both kind of samples. The effect of radiation induced chain breaks generation in pectin molecules was evident through the viscosity reduction of irradiated pectin solutions although the viscosity presented diverse values depending of the degree of methoxylation of carboxyl groups in the backbone of polysaccharide macromolecules. (author)

Optimization of pectin extraction and antioxidant activities from Jerusalem artichoke

Science.gov (United States)

Liu, Shengyi; Shi, Xuejie; Xu, Lanlan; Yi, Yuetao

2016-03-01

Jerusalem artichoke is an economic crop widely planted in saline-alkaline soil. The use of Jerusalem artichoke is of great significance. In this study, the response surface method was employed to optimize the effects of processing variables (extraction temperature, pH, extraction time, and liquid-to-solid ratio) on the yield of Jerusalem artichoke pectin. Under the optimal extraction conditions: pH 1.52, 63.62 min, 100°C and a liquid-to-solid ratio of 44.4 mL/g, the maximum pectin yield was predicted to be 18.76%. Experiments were conducted under these optimal conditions and a pectin yield of 18.52±0.90% was obtained, which validated the model prediction. The effects of diff erent drying methods (freeze drying, spray drying and vacuum drying) on the properties of Jerusalem artichoke pectin were evaluated and they were compared with apple pectin. FTIR spectral analysis showed no major structural diff erences in Jerusalem artichoke pectin samples produced by various drying treatments. The antioxidant activities of pectin dried by diff erent methods were investigated using in vitro hydroxyl and DPPH radical scavenging systems. The results revealed that the activities of spray dried pectin (SDP) and apple pectin (AP) were stronger than those of vacuum oven dried pectin (ODP) and vacuum freeze dried pectin (FDP). Therefore compared with the other two drying methods, the spray drying method was the best.

An array of possibilities for pectin

DEFF Research Database (Denmark)

Sørensen, Iben; Pedersen, Henriette Lodberg; Willats, William G T

2008-01-01

Pectins are a major component of plant cell walls and have numerous roles in plant growth and development. Extracted pectins are widely used as functional food ingredients in products including ice creams, jams, jellies and milk drinks. Although all are based on a galacturonan-rich backbone...

Complex formation ions calcium with macromolecules pectin

International Nuclear Information System (INIS)

Khalikova, M.D.; Avloev, Kh.Kh.; Muhiddinov, Z.K.

2005-01-01

In clause the mechanism of sorption of ions of calcium by macromolecules of pectin is opened. Is shown, that the linkage of ions of calcium descends on acid bunches of pectin, and process carries cooperative character

Heat-modified citrus pectin induces apoptosis-like cell death and autophagy in HepG2 and A549 cancer cells.

Science.gov (United States)

Leclere, Lionel; Fransolet, Maude; Cote, Francois; Cambier, Pierre; Arnould, Thierry; Van Cutsem, Pierre; Michiels, Carine

2015-01-01

Cancer is still one of the leading causes of death worldwide, and finding new treatments remains a major challenge. Previous studies showed that modified forms of pectin, a complex polysaccharide present in the primary plant cell wall, possess anticancer properties. Nevertheless, the mechanism of action of modified pectin and the pathways involved are unclear. Here, we show that citrus pectin modified by heat treatment induced cell death in HepG2 and A549 cells. The induced cell death differs from classical apoptosis because no DNA cleavage was observed. In addition, Z-VAD-fmk, a pan-caspase inhibitor, did not influence the observed cell death in HepG2 cells but appeared to be partly protective in A549 cells, indicating that heat-modified citrus pectin might induce caspase-independent cell death. An increase in the abundance of the phosphatidylethanolamine-conjugated Light Chain 3 (LC3) protein and a decrease in p62 protein abundance were observed in both cell types when incubated in the presence of heat-modified citrus pectin. These results indicate the activation of autophagy. To our knowledge, this is the first time that autophagy has been revealed in cells incubated in the presence of a modified form of pectin. This autophagy activation appears to be protective, at least for A549 cells, because its inhibition with 3-methyladenine increased the observed modified pectin-induced cytotoxicity. This study confirms the potential of modified pectin to improve chemotherapeutic cancer treatments.

Heat-modified citrus pectin induces apoptosis-like cell death and autophagy in HepG2 and A549 cancer cells.

Directory of Open Access Journals (Sweden)

Lionel Leclere

Full Text Available Cancer is still one of the leading causes of death worldwide, and finding new treatments remains a major challenge. Previous studies showed that modified forms of pectin, a complex polysaccharide present in the primary plant cell wall, possess anticancer properties. Nevertheless, the mechanism of action of modified pectin and the pathways involved are unclear. Here, we show that citrus pectin modified by heat treatment induced cell death in HepG2 and A549 cells. The induced cell death differs from classical apoptosis because no DNA cleavage was observed. In addition, Z-VAD-fmk, a pan-caspase inhibitor, did not influence the observed cell death in HepG2 cells but appeared to be partly protective in A549 cells, indicating that heat-modified citrus pectin might induce caspase-independent cell death. An increase in the abundance of the phosphatidylethanolamine-conjugated Light Chain 3 (LC3 protein and a decrease in p62 protein abundance were observed in both cell types when incubated in the presence of heat-modified citrus pectin. These results indicate the activation of autophagy. To our knowledge, this is the first time that autophagy has been revealed in cells incubated in the presence of a modified form of pectin. This autophagy activation appears to be protective, at least for A549 cells, because its inhibition with 3-methyladenine increased the observed modified pectin-induced cytotoxicity. This study confirms the potential of modified pectin to improve chemotherapeutic cancer treatments.

Foaming and emulsifying properties of pectin isolated from different plant materials

Science.gov (United States)

Yancheva, Nikoleta; Markova, Daniela; Murdzheva, Dilyana; Vasileva, Ivelina; Slavov, Anton

2016-03-01

The foaming and emulsifying properties of pectins obtained from waste rose petals, citrus pressings, grapefruit peels and celery were studied. It was found that the highest foaming capacity showed pectin derived from celery. The effect of pectin concentration on the foaming capacity of pectin solutions was investigated. For all the investigated pectins increasing the concentration led to increase of the foaming capacity. Emulsifying activity and emulsion stability of model emulsion systems (50 % oil phase) with 0.6 % pectic solutions were determined. The highest emulsifying activity and stability showed pectin isolated by dilute acid extraction from waste rose petals.

Foaming and emulsifying properties of pectin isolated from different plant materials

Directory of Open Access Journals (Sweden)

Yancheva Nikoleta

2016-03-01

Full Text Available The foaming and emulsifying properties of pectins obtained from waste rose petals, citrus pressings, grapefruit peels and celery were studied. It was found that the highest foaming capacity showed pectin derived from celery. The effect of pectin concentration on the foaming capacity of pectin solutions was investigated. For all the investigated pectins increasing the concentration led to increase of the foaming capacity. Emulsifying activity and emulsion stability of model emulsion systems (50 % oil phase with 0.6 % pectic solutions were determined. The highest emulsifying activity and stability showed pectin isolated by dilute acid extraction from waste rose petals.

The effect of copper ions, aluminium ions and their mixtures on separation of pectin from the sugar beet juice

Directory of Open Access Journals (Sweden)

Kuljanin Tatjana A.

2013-01-01

Full Text Available In sugar industry there is a problem of the presence of undesirable macromolecules compounds such as pectin in sugar beet juice. The affinity of calcium ions commonly used in the sugar industry for the removal of pectin from the sugar beet juice is relatively small. Coagulation and precipitation of pectin can be performed by process of discharging that is chemically induced. Compounds with di- and trivalent cations such as pure CuSO4, Al2(SO43 or their mixtures can be applied for clarification of pectin colloidal systems. According to data from the order of pectin selectivity to divalent metal ions, Cu2+ ions are the first order of ion binding. Also, aluminum sulfate is commonly used in the waste water treatment. Two model solutions of pectin whose concentration corresponds to the concentration of these macromolecules in sugar beet juice (0.1% w/w are investigated. Using a method of measuring zeta potential, it was proven for both investigated pectin that fewer quantities of Cu2+ ions compared to the values of Al3+ ions are needed to reach zero zeta potential. In all the investigated coagulants and their mixtures, zeta potential has changed the sign. In experiments with mixtures has been shown that pure salts showed better coagulation properties. The reduced strength of binding of cations in the case of most of the applied mixture of Cu2+ and Al3+ ions, can be explained by the mutual competition of these ions for the adsorption site (COO- groups on the surface of macromolecules. Mixture with approximately equal shares of ions Cu2+ and Al3+ had the most unfavorable coagulation ability (ion antagonism. Mechanism of discharge as well as the model of double electric layer surrounding pectin macromolecules in the presence of mixtures of Cu2+ and Al3+ ions are suggested. However, due to possible undesirable effects of CuSO4 on food processing, Al2(SO43 is proposed instead of traditional coagulant CaO, not only because of lower consumptions of

Preparation and characterization of collagen-hydroxyapatite/pectin composite.

Science.gov (United States)

Wenpo, Feng; Gaofeng, Liang; Shuying, Feng; Yuanming, Qi; Keyong, Tang

2015-03-01

Pectin, a kind of plant polysaccharide, was introduced into collagen-hydroxyapatite composite system, and prepared collagen-hydroxyapatite/pectin (Col-HA/pectin) composite in situ. The structure of the composite was investigated by XRD, SEM, and FT-IR. The mechanical properties, water absorption, enzyme degradation, and cytotoxicity of the composite were investigated as well. The results show that the inorganic substance in the composite materials is hydroxyapatite in relatively low crystallinity. A new interface appeared by the interaction among hydroxyapatite and collagen-pectin, and formed smooth fine particles. The mechanical properties, water absorption, enzyme degradation, and cytotoxicity indicate a potential use in bone replacement for the new composite. Copyright © 2014 Elsevier B.V. All rights reserved.

Proto pectin degradation of raw material by the acid hydrolysis

International Nuclear Information System (INIS)

Khalikov, D.Kh.; Gorshkova, R.M.; Khalikova, S.; Avloev, Kh.Kh.; Mukhiddinov, Z.K.

2007-01-01

The article presents results of hydrolysis proto pectin apples, an orange and a basket of sunflower depending on ph a solution. The reaction products are divided into three fractions conditionally named as micro gel, pectin substances and oligosaccharide. It was shown that the high-quality pectin extracted from orange, but high percentage of carboxylic group in the sunflower pectin allow it to by used as a drug delivery materials

Mechanical properties, structure, bioadhesion, and biocompatibility of pectin hydrogels.

Science.gov (United States)

Markov, Pavel A; Krachkovsky, Nikita S; Durnev, Eugene A; Martinson, Ekaterina A; Litvinets, Sergey G; Popov, Sergey V

2017-09-01

The surface structure, biocompatibility, textural, and adhesive properties of calcium hydrogels derived from 1, 2, and 4% solutions of apple pectin were examined in this study. An increase in the pectin concentration in hydrogels was shown to improve their stability toward elastic and plastic deformation. The elasticity of pectin hydrogels, measured as Young's modulus, ranged from 6 to 100 kPa. The mechanical properties of the pectin hydrogels were shown to correspond to those of soft tissues. The characterization of surface roughness in terms of the roughness profile (Ra) and the root-mean-square deviation of the roughness profile (Rq) indicated an increased roughness profile for hydrogels depending on their pectin concentration. The adhesion of AU2% and AU4% hydrogels to the serosa abdominal wall, liver, and colon was higher than that of the AU1% hydrogel. The adhesion of macrophages and the non-specific adsorption of blood plasma proteins were found to increase as the pectin concentration in the hydrogels increased. The rate of degradation of all hydrogels was higher in phosphate buffered saline (PBS) than that in DMEM and a fibroblast cell monolayer. The pectin hydrogel was also found to have a low cytotoxicity. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2572-2581, 2017. © 2017 Wiley Periodicals, Inc.

Comparison of Pectin Hydrogel Collection Methods in Microfluidic Device

Energy Technology Data Exchange (ETDEWEB)

Kim, Chaeyeon; Park, Ki-Su; Kang, Sung-Min; Kim, Jongmin; Song, YoungShin; Lee, Chang-Soo [Chungnam National University, Daejeon (Korea, Republic of)

2015-12-15

This study investigated the effect of different collection methods on physical properties of pectin hydrogels in microfluidic synthetic approach. The pectin hydrogels were simply produced by the incorporation of calcium ions dissolved in continuous mineral oil. Then, different collection methods, pipetting, tubing, and settling, for harvesting pectin hydrogels were applied. The settling method showed most uniform and monodispersed hydrogels. In the case of settling, a coefficient of variation was 3.46 which was lower than pipetting method (18.60) and tubing method (14.76). Under the settling method, we could control the size of hydrogels, ranging from 30 μm to 180 μm, by simple manipulation of the viscosity of pectin and volumetric flow rate of dispersed and continuous phase. Finally, according to the characteristics of simple encapsulation of biological materials, we envision that the pectin hydrogels can be applied to drug delivery, food, and biocompatible materials.

Extraction and characterisation of pomace pectin from gold kiwifruit (Actinidia chinensis).

Science.gov (United States)

Yuliarti, Oni; Goh, Kelvin K T; Matia-Merino, Lara; Mawson, John; Brennan, Charles

2015-11-15

Gold kiwifruit pomace extracted using citric acid, water and enzyme (Celluclast 1.5L) were studied in terms of pectin yield, protein, ash, non-starch polysaccharide, galacturonic acid (GalA), neutral sugar composition, molar mass (Mw), viscosity and degree of branching. Water-extracted pectin was considered closest to its native form. Enzyme extracted pectin showed the highest yield (∼ 4.5%w/w) as compared with the acid and water extraction methods (∼ 3.6-3.8%w/w). Pectin obtained from different extraction methods showed different degree of branching. The Mw and root mean square (RMS) radius varied with the extraction methods with values of 8.4 × 10(5) g/mol and 92 nm, 8.5 × 10(5)g/mol and 102 nm, 6.7 × 10(5) g/mol and 52 nm for acid, water and enzymatic extraction methods, respectively. Similar trend was observed for pectin viscosity, with water-extracted pectin giving a slightly higher viscosity followed by acid and enzyme-extracted pectin. This study showed that gold kiwifruit pomace pectin has potential application in food products. Copyright © 2015 Elsevier Ltd. All rights reserved.

Application of Pectin From Rauvolfia serpentina (L.) Benth to the Cryopreservation of Human Leucocyte Cell Suspensions.

Science.gov (United States)

Zaitseva, O O; PoleZhaeva, T V; Khudvakov, A N; Solomina, O N; Golovchenko, V V

　　BACKGROUND: Due to their valuable medicinal properties and high physiological activity, plant polysaccharides are currently being extensively studied. The present study aims to investigate rauwolfian (pectin for Rauvolfia serpentina) supplementation on human leukocytes cryopreservation. We determined the сharacteristics of leukocytes undergoing freezing with pectin at different temperatures. Donor leukocytes were frozen under the protection of comprehensive cryoprotectant solution and stored in electrical freezers (-20C, -40C, -80C). A regular decrease of all values starting from a higher temperature (-20С) through to the lower temperature (-80С) was identified. The study showed that pectin rauwolfian stimulated both the oxygen-independent and the oxygen-dependent killer response. We also found that the oxygen-dependent neutrophil killer effect was reduced as the storage temperature was lowered. It was determined that the LPO levels in the cells with added pectin-containing solutions remained the same before freezing, while their antioxidant activity positively increased, which is beneficial for neutrophils for their further freezing to -20C, -40C and -80C. The results of the study make it possible to assume that rauwolfian, a pectin extracted from Rauvolfia serpentina, has an exocellular protectant effect as part of cryopreservative solution on human white blood cells stored at different low temperatures. The versatility of the substance is probably due to the degree of the macromolecule branching, in particular, the structure of carbohydrate side chains, which contain a large number of hydroxyl groups.

Pulsed electric field-assisted modification of pectin from sugar beet pulp.

Science.gov (United States)

Ma, Sen; Wang, Zhong-he

2013-02-15

This current work is concerned with the modification of sugar beet pulp (SBP) pectin assisted by pulsed electric filed (PEF) without solvent. Pectin-arachates with degree of esterification (DE) ranging from 49 to 84 were prepared in one-step modification. The results showed that the DE of pectin derivatives increased significantly with the PEF intensity from 18 to 30 kV cm((1) and total specific energy input from 124 to 345 J mL((1). Evidence of modification of pectin was provided by FT-IR, X-ray diffraction patterns and NMR spectra. Thermogravimetric investigation of modified pectin indicated a higher thermal stability than the untreated one. Results revealed that PEF technology is a promising method for industrial manufacture of pectin derivatives. Copyright © 2012 Elsevier Ltd. All rights reserved.

Environmentally friendly preparation of pectins from agricultural byproducts and their structural/rheological characterization.

Science.gov (United States)

Min, Bockki; Lim, Jongbin; Ko, Sanghoon; Lee, Kwang-Geun; Lee, Sung Ho; Lee, Suyong

2011-02-01

Apple pomace which is the main waste of fruit juice industry was utilized to extract pectins in an environmentally friendly way, which was then compared with chemically-extracted pectins. The water-based extraction with combined physical and enzymatic treatments produced pectins with 693.2 mg g(-1) galacturonic acid and 4.6% yield, which were less than those of chemically-extracted pectins. Chemically-extracted pectins exhibited lower degree of esterification (58%) than the pectin samples obtained by physical/enzymatic treatments (69%), which were also confirmed by FT-IR analysis. When subjected to steady-shear rheological conditions, both pectin solutions were shown to have shear-thinning properties. However, decreased viscosity was observed in the pectins extracted by combined physical/enzymatic methods which could be mainly attributed to the presence of more methyl esters, thus limiting polymer chain interactions. Moreover, the pectins which were extracted by combined physical/enzymatic treatments, showed less elastic properties under high shear rate conditions, compared to the chemically-extracted pectins. Copyright © 2010 Elsevier Ltd. All rights reserved.

Calcium Pectinate Beads Formation: Shape and Size Analysis

Directory of Open Access Journals (Sweden)

Boon-Beng Lee

2014-04-01

Full Text Available The aim of this study was to investigate the inter-relationship between process variables and the size and shape of pectin solution droplets upon detachment from a dripping tip as well as Ca-pectinate beads formed after gelation via image analysis. The sphericity factor (SF of the droplets was generally smaller than 0.05. There was no specific trend between the SF of the droplets and the pectin concentration or the dripping tip radius. The SF the beads formed from high-concentration pectin solutions and a small dripping tip was smaller than 0.05. The results show that the Reynolds number and Ohnesorge number of the droplets fall within the operating region for forming spherical beads in the shape diagram, with the exception to the lower boundary. The lower boundary of the operating region has to be revised to Oh = 2.3. This is because the critical viscosity for Ca-pectinate bead formation is higher than that of Ca-alginate beads. On the other hand, the radius of the droplets and beads increased as the dripping tip radius increased. The bead radius can easily be predicted by Tate’s law equation.

Cellular growth in plants requires regulation of cell wall biochemistry.

Science.gov (United States)

Chebli, Youssef; Geitmann, Anja

2017-02-01

Cell and organ morphogenesis in plants are regulated by the chemical structure and mechanical properties of the extracellular matrix, the cell wall. The two primary load bearing components in the plant cell wall, the pectin matrix and the cellulose/xyloglucan network, are constantly remodelled to generate the morphological changes required during plant development. This remodelling is regulated by a plethora of loosening and stiffening agents such as pectin methyl-esterases, calcium ions, expansins, and glucanases. The tight spatio-temporal regulation of the activities of these agents is a sine qua non condition for proper morphogenesis at cell and tissue levels. The pectin matrix and the cellulose-xyloglucan network operate in concert and their behaviour is mutually dependent on their chemical, structural and mechanical modifications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Oxidative enzymatic gelation of sugar beet pectin for emulsion stabilization

DEFF Research Database (Denmark)

Abang Zaidel, Dayang Norulfairuz; Meyer, Anne S.

2013-01-01

Pectin from sugar beet is derived from the sugar beet pulp residue which results when sugar beets are processed for sucrose extraction. The sugar beet pectin has poor gelationability by the classic divalentcation molecular mechanism because of a relatively high acetylation degree and short...... polygalacturonate backbone chain length. However, due to the feruloyl-substitutions on the side chains, the sugar beet pectic polysaccharides can be cross-linked via enzyme catalyzed oxidation. The enzyme kinetics and functionality of such oxidativelycross-linked sugar beet pectin, in relation to stabilizing...... emulsions has recently been investigated in model food emulsions. This paper reviews the pectin chemistry, enzymatic oxidative gelation mechanisms, interaction mechanisms of the sugar beet pectin with the emulsion droplets and explores how the gelation affects the rheology and stability of emulsion systems...

Mucoadhesive Properties of Thiolated Pectin-Based Pellets Prepared by Extrusion-Spheronization Technique.

Science.gov (United States)

Martins, André Luiz Lopes; de Oliveira, Aline Carlos; do Nascimento, Carolina Machado Ozório Lopes; Silva, Luís Antônio Dantas; Gaeti, Marilisa Pedroso Nogueira; Lima, Eliana Martins; Taveira, Stephânia Fleury; Fernandes, Kátia Flávia; Marreto, Ricardo Neves

2017-05-01

The aim of this study was to develop mucoadhesive pellets on a thiolated pectin base using the extrusion-spheronization technique. Thiolation of pectin was performed by esterification with thioglycolic acid. The molecular weight and thiol group content of the pectins were determined. Pellets containing pectin, microcrystalline cellulose, and ketoprofen were prepared and their mucoadhesive properties were evaluated through a wash-off test using porcine intestinal mucosa. The in vitro ketoprofen release was also evaluated. Thiolated pectin presented a thiol group content of 0.69 mmol/g. Thiolation caused a 13% increase in polymer molecular weight. Pellets containing thiolated pectin were still adhering to the intestinal mucosa after 480 min and showed a more gradual release of ketoprofen. Conversely, pellets prepared with nonthiolated pectin showed rapid disintegration and detached after only 15 min. It can be concluded that thiolated pectin-based pellets can be considered a potential platform for the development of mucoadhesive drug delivery systems for the oral route. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Pectin-rich biomass as feedstock for fuel ethanol production.

Science.gov (United States)

Edwards, Meredith C; Doran-Peterson, Joy

2012-08-01

The USA has proposed that 30 % of liquid transportation fuel be produced from renewable resources by 2030 (Perlack and Stokes 2011). It will be impossible to reach this goal using corn kernel-based ethanol alone. Pectin-rich biomass, an under-utilized waste product of the sugar and juice industry, can augment US ethanol supplies by capitalizing on this already established feedstock. Currently, pectin-rich biomass is sold (at low value) as animal feed. This review focuses on the three most studied types of pectin-rich biomass: sugar beet pulp, citrus waste and apple pomace. Fermentations of these materials have been conducted with a variety of ethanologens, including yeasts and bacteria. Escherichia coli can ferment a wide range of sugars including galacturonic acid, the primary component of pectin. However, the mixed acid metabolism of E. coli can produce unwanted side products. Saccharomyces cerevisiae cannot naturally ferment galacturonic acid nor pentose sugars but has a homoethanol pathway. Erwinia chrysanthemi is capable of degrading many of the cell wall components of pectin-rich materials, including pectin. Klebsiella oxytoca can metabolize a diverse array of sugars including cellobiose, one degradation product of cellulose. However, both E. chrysanthemi and K. oxytoca produce side products during fermentation, similar to E. coli. Using pectin-rich residues from industrial processes is beneficial because the material is already collected and partially pretreated to facilitate enzymatic deconstruction of the plant cell walls. Using biomass already produced for other purposes is an attractive practice because fewer greenhouse gases (GHG) will be anticipated from land-use changes.

Pectin-rich biomass as feedstock for fuel ethanol production

Energy Technology Data Exchange (ETDEWEB)

Edwards, Meredith C.; Doran-Peterson, Joy [Georgia Univ., Athens, GA (United States). Dept. of Microbiology

2012-08-15

The USA has proposed that 30 % of liquid transportation fuel be produced from renewable resources by 2030 (Perlack and Stokes 2011). It will be impossible to reach this goal using corn kernel-based ethanol alone. Pectin-rich biomass, an under-utilized waste product of the sugar and juice industry, can augment US ethanol supplies by capitalizing on this already established feedstock. Currently, pectin-rich biomass is sold (at low value) as animal feed. This review focuses on the three most studied types of pectin-rich biomass: sugar beet pulp, citrus waste and apple pomace. Fermentations of these materials have been conducted with a variety of ethanologens, including yeasts and bacteria. Escherichia coli can ferment a wide range of sugars including galacturonic acid, the primary component of pectin. However, the mixed acid metabolism of E. coli can produce unwanted side products. Saccharomyces cerevisiae cannot naturally ferment galacturonic acid nor pentose sugars but has a homoethanol pathway. Erwinia chrysanthemi is capable of degrading many of the cell wall components of pectin-rich materials, including pectin. Klebsiella oxytoca can metabolize a diverse array of sugars including cellobiose, one degradation product of cellulose. However, both E. chrysanthemi and K. oxytoca produce side products during fermentation, similar to E. coli. Using pectin-rich residues from industrial processes is beneficial because the material is already collected and partially pretreated to facilitate enzymatic deconstruction of the plant cell walls. Using biomass already produced for other purposes is an attractive practice because fewer greenhouse gases (GHG) will be anticipated from land-use changes. (orig.)

Effects of high hydrostatic pressure on the overall quality of Pêra-Rio orange juice during shelf life.

Science.gov (United States)

Spira, Paz; Bisconsin-Junior, Antonio; Rosenthal, Amauri; Monteiro, Magali

2018-01-01

The effect of high hydrostatic pressure on antioxidant activity, total phenolic compounds, physicochemical characteristics, color, pectin methylesterase activity, and microbiological count were evaluated during the shelf life of Pêra-Rio orange juice. Pressurized (520 MPa, 60 ℃, for 360 s), non-processed and pasteurized (95 ℃/30 s) orange juice were compared at zero time of storage. Pressurized and pasteurized juices were studied during a refrigerated 90-day shelf life. Pressurization did not cause expressive change in physicochemical characteristics of Pêra-Rio orange juice along shelf life, but significantly reduced pectin methylesterase residual activity to 13% and microbiological counts below detection levels up to 68 days of storage, with small counts (30.0 × 10 CFU/mL mesophilic aerobic bacteria and 20.7 × 10 CFU/mL yeast and mold) at 90 days, capable of ensuring the juice's stability along shelf life. Lightness ( L*) and b* values were significantly reduced by high hydrostatic pressure during shelf life, while a* values were significantly higher. Ascorbic acid decreased around 80% during shelf life. Antioxidant activity remained stable after processing and during storage.

Prediction of Pectin Yield and Quality by FTIR and Carbohydrate Microarray Analysis

DEFF Research Database (Denmark)

Baum, Andreas; Dominiak, Malgorzata Maria; Vidal-Melgosa, Silvia

2017-01-01

and carbohydrate microarray analysis were performed directly on the crude lime peel extracts during the time course of the extractions. Multivariate analysis of the data was carried out to predict final pectin yields. Fourier transform infrared spectroscopy (FTIR) was found applicable for determining the optimal...... extraction time for the enzymatic and acidic extraction processes, respectively. The combined results of FTIR and carbohydrate microarray analysis suggested major differences in the crude pectin extracts obtained by enzymatic and acid extraction, respectively. Enzymatically extracted pectin, thus, showed......, and that FTIR and carbohydrate microarray analysis have potential to be developed into online process analysis tools for prediction of pectin extraction yields and pectin features from measurements on crude pectin extracts....

Effects of pectin-containing diets on the hepatic macromolecular covalent binding of 2,6-dinitro-[3H]toluene in Fischer-344 rats

International Nuclear Information System (INIS)

deBethizy, J.D.; Sherrill, J.M.; Rickert, D.E.; Hamm, T.E. Jr.

1983-01-01

The influence of diets varying in pectin content on intestinal microfloral metabolic capacity of rats has been investigated as a possible mechanism for the alteration of toxicity of 2,6-dinitrotoluene (2,6-DNT) produced by these diets. Male F-344 rats were fed a purified diet (AIN-76A), AIN-76A plus 5% or 10% citrus pectin, or either of two cereal-based diets that vary in pectin content, NIH-07 or Purina Chow 5002. After 28 days, rats were given tritium-labeled 2,6-DNT (10 or 75 mg/kg po) and killed 12 hr later. Total hepatic macromolecular covalent binding (CVB) was determined by exhaustive extraction. The CVB of 2,6-DNT was found to be independent of diet at 10 mg/kg. However, at 75 mg/kg CVB was increased 40% by feeding 5% pectin in the purified diet and 90% by feeding 10% pectin in the purified diet. Animals fed Purina 5002 and NIH-07 had 135 and 150% higher CVB, respectively, than animals fed the purified diet alone and significantly greater CVB than animals fed the pectin supplemented diets. Elevated (two- to threefold) beta-glucuronidase and nitroreductase activities, microfloral enzymes proposed to be involved in the activation of 2,6-DNT to a toxicant, were found in the cecal contents of animals fed the pectin-containing diets which correlated with a two- to threefold increase in total number of cecal anaerobes. These results suggest that pectin-induced changes in microflora may enhance hepatoxicity after high doses of 2,6-DNT

The Role of Pectin in Pb Binding by Carrot Peel Biosorbents: Isoterm Adsorption Study

Science.gov (United States)

Hastuti, B.; Totiana, F.; Winiasih, R.

2018-04-01

Cheaply and abundantly biosorption available materials such as carrot peels can be a cost-efficient method for removing heavy metals from wastewater. To investigate the role pectin plays in metal binding by carrot peels, commerce pectin was compared. FTIR spectra confirmed the presence of carboxyl and hydroxyl groups in commerce pectin and carrot pectin. Isoterm experiments showed that all materials could remove Pb (II) ion. All of materials binding Pb (II) follow Freundlich models adsorption. The commerce pectin bindsPb (II) by involving energy 16.6 KJ/mole whereas pectin from carrot peel involves energy 21.09 KJ/mole. It indicates that commerce pectin binds the Pb (II) by physics adsorption whereas pectin from carrot peel by physics and chemical adsorption.

A novel perspective on pectin extraction

DEFF Research Database (Denmark)

Dominiak, Malgorzata Maria

optimization is a long process because the evaluation of the final product quality is accomplished at the end of the procedure, employing time-consuming off-line laboratory tests. Fourier transform infrared spectroscopy (FTIR) and carbohydrate microarrays, combined with chemometrics, were evaluated...... determined the optimal extraction time for both the enzymatic and acidic extraction processes. The combined results suggested major differences in the crude pectin extract traits of enzymatically vs. acidically extracted pectin with respect to the degree of esterification, purity, and abundance...

Pectin: new insights into an old polymer are starting to gel

DEFF Research Database (Denmark)

Willats, W. G. T.; Knox, J. P.; Mikkelsen, J. D.

2006-01-01

the structure and functionalities of pectic polymers at the molecular level. The basic properties of pectin have been known for nearly 200 years, but recently there has been tremendous progress in our understanding of the very complex fine structure of pectic polymers and pectinolytic enzymes. This has been....... Producers are beginning to develop a new generation of sophisticated designer pectins with specific functionalities. Moreover, the ability to manipulate pectin in planta would have a major impact on fruit and vegetable quality and processing, as well as on pectin production....

Isolation of pectin from pumpkin (Cucurbita moschata, L.) by acid hydrolysis

International Nuclear Information System (INIS)

Souza, Jose R.R.; Ricardo, Nagila M.P.S.; Paula, Regina C.M. de; Feitosa, Judith P.A.

2009-01-01

Pumpkin (Cucurbita moschata, L.) constitutes an excellent source of carotenoids, precursors of vitamin A. Besides, it also that constitutes also a great natural source of low-cost pectin. Pectin is a heterogeneous complex polysaccharide found in the primary cell wall of most plants and its effect on health is receiving increasing interest from the scientific community. In this work, high-methoxy pectin was obtained from pumpkin (Cucurbita moschata, L.) through the acid hydrolysis methodology. The pectin obtained was characterized by FTIR, NMR 1 H, GPC and rheology. (author)

Pectin gelation with chlorhexidine: Physico-chemical studies in dilute solutions.

Science.gov (United States)

Lascol, Manon; Bourgeois, Sandrine; Guillière, Florence; Hangouët, Marie; Raffin, Guy; Marote, Pedro; Lantéri, Pierre; Bordes, Claire

2016-10-05

Low methoxyl pectin is known to gel with divalent cations (e.g. Ca(2+), Zn(2+)). In this study, a new way of pectin gelation in the presence of an active pharmaceutical ingredient, chlorhexidine (CX), was highlighted. Thus chlorhexidine interactions with pectin were investigated and compared with the well-known pectin/Ca(2+) binding model. Gelation mechanisms were studied by several physico-chemical methods such as zeta potential, viscosity, size measurements and binding isotherm was determined by Proton Nuclear Magnetic Resonance Spectroscopy ((1)H NMR). The binding process exhibited similar first two steps for both divalent ions: a stoichiometric monocomplexation of the polymer followed by a dimerization step. However, stronger interactions were observed between pectin and chlorhexidine. Moreover, the dimerization step occurred under stoichiometric conditions with chlorhexidine whereas non-stoichiometric conditions were involved with calcium ions. In the case of chlorhexidine, an additional intermolecular binding occurred in a third step. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pectin from Citrus Canning Wastewater as Potential Fat Replacer in Ice Cream

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Hua Zhang

2018-04-01

Full Text Available Pectin had been recovered from canning wastewater produced by chemical treatment of segment membrane during preparation of canned citrus in our previous research. The purpose of this study was to characterize the extracted pectin from canning wastewater, and to evaluate its application as a fat alternative to replace fat in ice cream. The monosaccharide composition and rheological properties of the pectin were determined. The influences of fat reduction and pectin addition on the physicochemical, rheological and sensory properties of low-fat ice cream were determined. The rheological results showed that pectin solutions were typical pseudoplastic fluids. The addition of pectin in ice cream can cause an increase in viscosity, overrun, and hardness, and a decrease in meltdown of the ice cream. When 0.72% pectin (w/w is incorporated into ice cream, a prototype product of ice cream with 45% lower fat content compared to the control was made. Results indicated that their qualities such as appearance, flavor, and taste were not significantly different. The low-fat ice cream had higher smoothness scores and lower mouth-coating scores. Hence, pectin extracted from citrus canning wastewater can be potentially used as fat replacer in ice cream, which benefits both the environment and the food industry.

Pectin from Citrus Canning Wastewater as Potential Fat Replacer in Ice Cream.

Science.gov (United States)

Zhang, Hua; Chen, Jianle; Li, Junhui; Wei, Chaoyang; Ye, Xingqian; Shi, John; Chen, Shiguo

2018-04-17

Pectin had been recovered from canning wastewater produced by chemical treatment of segment membrane during preparation of canned citrus in our previous research. The purpose of this study was to characterize the extracted pectin from canning wastewater, and to evaluate its application as a fat alternative to replace fat in ice cream. The monosaccharide composition and rheological properties of the pectin were determined. The influences of fat reduction and pectin addition on the physicochemical, rheological and sensory properties of low-fat ice cream were determined. The rheological results showed that pectin solutions were typical pseudoplastic fluids. The addition of pectin in ice cream can cause an increase in viscosity, overrun, and hardness, and a decrease in meltdown of the ice cream. When 0.72% pectin ( w / w ) is incorporated into ice cream, a prototype product of ice cream with 45% lower fat content compared to the control was made. Results indicated that their qualities such as appearance, flavor, and taste were not significantly different. The low-fat ice cream had higher smoothness scores and lower mouth-coating scores. Hence, pectin extracted from citrus canning wastewater can be potentially used as fat replacer in ice cream, which benefits both the environment and the food industry.

Physicochemical Characteristics and Biological Activity of Irradiated Pectin Solution

International Nuclear Information System (INIS)

Kwon, J.H.; Kang, H.J.; Jo, C.O.; Jeong, I.Y.; Byun, M.W.

2005-01-01

Pectin was dissolved in HCI, citric acid, and deionized distilled water (DW, 2%, v/v) and irradiated at different irradiation doses (2.5-50 kGy) by gamma ray to investigate its physicochemical characteristics and biological activity. Viscosity of pectin solution was significantly decreased by irradiation up to 10 kGy, then remained constant thereafter. Gamma-irradiation increased monosaccharide and polysaccharide levels up to 30-40 kDa. Electron donating ability of pectin solution was highest when DW was added was increased by increasing irradiation dose (p less than 0.05)

Orange pectin mediated growth and stability of aqueous gold and silver nanocolloids

International Nuclear Information System (INIS)

Nigoghossian, Karina; Santos, Molíria V. dos; Barud, Hernane S.; Silva, Robson R. da; Rocha, Lucas A.; Caiut, José M.A.; Assunção, Rosana M.N. de; Spanhel, Lubomir; Poulain, Marcel; Messaddeq, Younes; Ribeiro, Sidney J.L.

2015-01-01

Graphical abstract: - Highlights: • Pectin from orange was used as stabilizer of Ag, Au and Ag–Au nanoparticles. • Sodium citrate, oxalic acid or pectin were used as reducing agents. • Colloids spanning all visible region were obtained depending on Ag/Au-ratio and pH. • Pectin is a highly efficient stabilizer of nanocolloidal solutions for years. - Abstract: The role of orange based pectin in the nucleation and growth of silver and gold nanoparticles is addressed. Pectin is a complex polysaccharide found in fruits such as oranges, lemons, passion fruits or apples. It displays smooth and hairy chain regions containing hydroxyl-, ester-, carboxylate- and eventually amine groups that can act as surface ligands interacting under various pH conditions more or less efficiently with growing nanometals. Here, a high methoxy pectin (>50% esterified) was used as a stabilizer/reducing agent in the preparation of gold, silver and silver–gold nanoparticles. Commercial pectin (CP) and pectin extracted from orange bagasse (OP) were used. Optionally, trisodium citrate or oxalic acid we used to reduce AgNO 3 and HAuCl 4 in aqueous environment. Characterization methods included UV–vis absorption spectroscopy, transmission electron microscopy, electron diffraction and energy-dispersive X-ray spectroscopy. The results show that under different pH conditions, pectin and reducing agents allow producing various nanostructures shapes (triangles, spheres, rods, octahedrons and decahedrons) often with high polydispersity and sizes ranging between 5 nm and 30 nm. In addition, depending on Ag/Au-ratio and pH, the surface plasmon bands can be continuously shifted between 410 nm and 600 nm. Finally, pectin seems to be a highly efficient stabilizer of the colloidal systems that show a remarkable stability and unchanged optical spectral response even after five years

Orange pectin mediated growth and stability of aqueous gold and silver nanocolloids

Energy Technology Data Exchange (ETDEWEB)

Nigoghossian, Karina; Santos, Molíria V. dos; Barud, Hernane S.; Silva, Robson R. da [Institute of Chemistry, São Paulo State University – UNESP, 14801-970 Araraquara, SP (Brazil); Rocha, Lucas A. [Departamento de Quimica, Universidade de Franca, Franca, SP (Brazil); Caiut, José M.A. [Departamento de Química, FFCLRP, USP, Ribeirão Preto, SP (Brazil); Assunção, Rosana M.N. de [Faculdade de Ciências Integradas do Pontal, Universidade Federal de Uberlândia, 38302-000 Ituiutaba, MG (Brazil); Spanhel, Lubomir [CEITEC-Central European Institute of Technology, Masaryk University Brno (Czech Republic); Institute of Chemical Sciences, University of Rennes 1, Campus Beaulieu, 35 042 Rennes (France); Poulain, Marcel [Institute of Chemical Sciences, University of Rennes 1, Campus Beaulieu, 35 042 Rennes (France); Messaddeq, Younes [Institute of Chemistry, São Paulo State University – UNESP, 14801-970 Araraquara, SP (Brazil); Ribeiro, Sidney J.L., E-mail: sidney@iq.unesp.br [Institute of Chemistry, São Paulo State University – UNESP, 14801-970 Araraquara, SP (Brazil)

2015-06-30

Graphical abstract: - Highlights: • Pectin from orange was used as stabilizer of Ag, Au and Ag–Au nanoparticles. • Sodium citrate, oxalic acid or pectin were used as reducing agents. • Colloids spanning all visible region were obtained depending on Ag/Au-ratio and pH. • Pectin is a highly efficient stabilizer of nanocolloidal solutions for years. - Abstract: The role of orange based pectin in the nucleation and growth of silver and gold nanoparticles is addressed. Pectin is a complex polysaccharide found in fruits such as oranges, lemons, passion fruits or apples. It displays smooth and hairy chain regions containing hydroxyl-, ester-, carboxylate- and eventually amine groups that can act as surface ligands interacting under various pH conditions more or less efficiently with growing nanometals. Here, a high methoxy pectin (>50% esterified) was used as a stabilizer/reducing agent in the preparation of gold, silver and silver–gold nanoparticles. Commercial pectin (CP) and pectin extracted from orange bagasse (OP) were used. Optionally, trisodium citrate or oxalic acid we used to reduce AgNO{sub 3} and HAuCl{sub 4} in aqueous environment. Characterization methods included UV–vis absorption spectroscopy, transmission electron microscopy, electron diffraction and energy-dispersive X-ray spectroscopy. The results show that under different pH conditions, pectin and reducing agents allow producing various nanostructures shapes (triangles, spheres, rods, octahedrons and decahedrons) often with high polydispersity and sizes ranging between 5 nm and 30 nm. In addition, depending on Ag/Au-ratio and pH, the surface plasmon bands can be continuously shifted between 410 nm and 600 nm. Finally, pectin seems to be a highly efficient stabilizer of the colloidal systems that show a remarkable stability and unchanged optical spectral response even after five years.

Structural changes in cell wall pectins during strawberry fruit development.

Science.gov (United States)

Paniagua, Candelas; Santiago-Doménech, Nieves; Kirby, Andrew R; Gunning, A Patrick; Morris, Victor J; Quesada, Miguel A; Matas, Antonio J; Mercado, José A

2017-09-01

Strawberry (Fragaria × anannasa Duch.) is one of the most important soft fruit. Rapid loss of firmness occurs during the ripening process, resulting in a short shelf life and high economic losses. To get insight into the role of pectin matrix in the softening process, cell walls from strawberry fruit at two developmental stages, unripe-green and ripe-red, were extracted and sequentially fractionated with different solvents to obtain fractions enriched in a specific component. The yield of cell wall material as well as the per fresh weight contents of the different fractions decreased in ripe fruit. The largest reduction was observed in the pectic fractions extracted with a chelating agent (trans-1,2- diaminocyclohexane-N,N,N'N'-tetraacetic acid, CDTA fraction) and those covalently bound to the wall (extracted with Na 2 CO 3 ). Uronic acid content of these two fractions also decreased significantly during ripening, but the amount of soluble pectins extracted with phenol:acetic acid:water (PAW) and water increased in ripe fruit. Fourier transform infrared spectroscopy of the different fractions showed that the degree of esterification decreased in CDTA pectins but increased in soluble fractions at ripen stage. The chromatographic analysis of pectin fractions by gel filtration revealed that CDTA, water and, mainly PAW polyuronides were depolymerised in ripe fruit. By contrast, the size of Na 2 CO 3 pectins was not modified. The nanostructural characteristics of CDTA and Na 2 CO 3 pectins were analysed by atomic force microscopy (AFM). Isolated pectic chains present in the CDTA fractions were significantly longer and more branched in samples from green fruit than those from red fruit. No differences in contour length were observed in Na 2 CO 3 strands between samples of both stages. However, the percentage of branched chains decreased from 19.7% in unripe samples to 3.4% in ripe fruit. The number of pectin aggregates was higher in green fruit samples of both

Sorption characteristics of pectin isolated from Jerusalem Artichoke tubers (Helianthus tuberosus L.

Directory of Open Access Journals (Sweden)

N. Toshkov

2015-05-01

Full Text Available Introduction. The aim of the present study is the isolation of pectin from Jerusalem artichoke tubers (Helianthus tuberosus L. and the analysis of its sorption characteristics Materials and methods. Research was carried out on the pectin content of the tubers of Jerusalem artichoke plants cultivated in Bulgaria. The polyuronide content (PUC was determined via the МсCready method. The static gravimetric method was used for analysis of the sorption characteristics of pectins. Results and discussion. The polysaccharide was extracted. The isolated pectins were analyzed in physical terms: the equilibrium sorption isotherms, belonging to type II in Brunauer’s classification, were obtained experimentally. The entire isotherm length demonstrated statistically significant hysteresis. The Henderson and Chung-Pfost models provided adequate isotherm description. The pectin content of the three Jerusalem artichoke samples is 14.8, 9.2 and 11.9 % a.d.m., respectively. The monomolecular moisture content of pectin was within the 7.42 – 7.92% dry basis range, its corresponding water activity value –within the 0.14 –0.16 range. Conclusion. The resultsof research are advisablefor use indevelop of functional food ingredient which is used pectin as a gelling agent and a stabilizer.

Characterization of gold kiwifruit pectin from fruit of different maturities and extraction methods.

Science.gov (United States)

Yuliarti, Oni; Matia-Merino, Lara; Goh, Kelvin K T; Mawson, John; Williams, Martin A K; Brennan, Charles

2015-01-01

Studies on gold kiwifruit pectins are limited. In this work, the characterization of pectin isolated from two different stages of maturity of gold kiwifruit, namely early harvested fruit (EHF) and main harvested fruit (MHF) isolated by three methods (acid, water, enzymatic) was carried out. Pectins isolated from MHF were higher in galacturonic acid content (52-59% w/w) and weight-average molecular weights (Mw, 1.7-3.8 × 10(6)g/mol) compared with EHF pectins (29-49% w/w and 0.2-1.7 × 10(6)g/mol respectively). Enzymatic treatment gave the highest yield but lowest in Mw, viscosity and mechanical spectra for both maturities. The pectin of both maturities was classified as high-methoxyl pectin with the degree of esterification ranged from 82% to 90%. Water-extracted MHF pectin molecules had the highest RMS radius (182.7 nm) and Mw (3.75 × 10(6)g/mol). The water extraction method appeared to retain the native state of pectin molecules compared with acid and enzymatic extraction methods based on the Mw and viscosity data. Copyright © 2014 Elsevier Ltd. All rights reserved.

Microbiological and Biochemical Characterization of Cassava Retting, a Traditional Lactic Acid Fermentation for Foo-Foo (Cassava Flour) Production

OpenAIRE

Brauman, A.; Keleke, S.; Malonga, M.; Miambi, E.; Ampe, F.

1996-01-01

The overall kinetics of retting, a spontaneous fermentation of cassava roots performed in central Africa, was investigated in terms of microbial-population evolution and biochemical and physicochemical parameters. During the traditional process, endogenous cyanogens were almost totally degraded, plant cell walls were lysed by the simultaneous action of pectin methylesterase and pectate lysate, and organic acids (C2 to C4) were produced. Most microorganisms identified were found to be facultat...

Identification of a cytotoxic molecule in heat-modified citrus pectin.

Science.gov (United States)

Leclere, Lionel; Fransolet, Maude; Cambier, Pierre; El Bkassiny, Sandy; Tikad, Abdellatif; Dieu, Marc; Vincent, Stéphane P; Van Cutsem, Pierre; Michiels, Carine

2016-02-10

Modified forms of citrus pectin possess anticancer properties. However, their mechanism of action and the structural features involved remain unclear. Here, we showed that citrus pectin modified by heat treatment displayed cytotoxic effects in cancer cells. A fractionation approach was used aiming to identify active molecules. Dialysis and ethanol precipitation followed by HPLC analysis evidenced that most of the activity was related to molecules with molecular weight corresponding to low degree of polymerization oligogalacturonic acid. Heat-treatment of galacturonic acid also generated cytotoxic molecules. Furthermore, heat-modified galacturonic acid and heat-fragmented pectin contained the same molecule that induced cell death when isolated by HPLC separation. Mass spectrometry analyses revealed that 4,5-dihydroxy-2-cyclopenten-1-one was one cytotoxic molecule present in heat-treated pectin. Finally, we synthesized the enantiopure (4R,5R)-4,5-dihydroxy-2-cyclopenten-1-one and demonstrated that this molecule was cytotoxic and induced a similar pattern of apoptotic-like features than heat-modified pectin. Copyright © 2015 Elsevier Ltd. All rights reserved.

Studies on the structure of industrial high methoxyl pectins

NARCIS (Netherlands)

Kravtchenko, T.P.

1992-01-01

The chemical structure of three industrial high methoxyl pectins (one extracted from apple pomace and two from lemon peels) has been extensively investigated. The apple pectin differs from the lemon ones by having a higher apparent molecular size, a higher neutral-sugar content, present

Cultured representatives of two major phylogroups of human colonic Faecalibacterium prausnitzii can utilize pectin, uronic acids, and host-derived substrates for growth.

Science.gov (United States)

Lopez-Siles, Mireia; Khan, Tanweer M; Duncan, Sylvia H; Harmsen, Hermie J M; Garcia-Gil, L Jesús; Flint, Harry J

2012-01-01

Faecalibacterium prausnitzii is one of the most abundant commensal bacteria in the healthy human large intestine, but information on genetic diversity and substrate utilization is limited. Here, we examine the phylogeny, phenotypic characteristics, and influence of gut environmental factors on growth of F. prausnitzii strains isolated from healthy subjects. Phylogenetic analysis based on the 16S rRNA sequences indicated that the cultured strains were representative of F. prausnitzii sequences detected by direct analysis of fecal DNA and separated the available isolates into two phylogroups. Most F. prausnitzii strains tested grew well under anaerobic conditions on apple pectin. Furthermore, F. prausnitzii strains competed successfully in coculture with two other abundant pectin-utilizing species, Bacteroides thetaiotaomicron and Eubacterium eligens, with apple pectin as substrate, suggesting that this species makes a contribution to pectin fermentation in the colon. Many F. prausnitzii isolates were able to utilize uronic acids for growth, an ability previously thought to be confined to Bacteroides spp. among human colonic anaerobes. Most strains grew on N-acetylglucosamine, demonstrating an ability to utilize host-derived substrates. All strains tested were bile sensitive, showing at least 80% growth inhibition in the presence of 0.5 μg/ml bile salts, while inhibition at mildly acidic pH was strain dependent. These attributes help to explain the abundance of F. prausnitzii in the colonic community but also suggest factors in the gut environment that may limit its distribution.

Effect of Celluclast 1.5L on the Physicochemical Characterization of Gold Kiwifruit Pectin

Directory of Open Access Journals (Sweden)

John A. Mawson

2011-09-01

Full Text Available The effects of Celluclast 1.5L concentration on the physicochemical characterization of gold kiwifruit pectin was evaluated. Varying the enzyme concentration affected the pectin yield and pectin physicochemical properties. The viscosity of extracted pectin was largely dependent on the enzyme concentration. Celluclast 1.5L with medium concentration exhibited the highest viscosity. Varying the enzyme concentration also influenced the molecular weight distribution. High molecular weight (Mw pectin (1.65 × 106 g/mol was obtained when the medium concentration was used. Overall, the study clearly reflects the importance of taking into consideration the amount of cellulytic enzyme added in order to determine the final quality of pectin.

Drying Kinetics and Optimisation of Pectin Extraction from Banana Peels via Response Surface Methodology

Directory of Open Access Journals (Sweden)

Bee Lin Chua

2018-01-01

Full Text Available Banana peels which are the waste in abundance, are used to extract valuable pectin. The gelling ability of the pectin has gained attention in food and pharmaceutical industries. This research aims to select the best drying kinetic model for banana peels and also optimize the pectin extraction process using Box-Behnken response surface design (BBD. Determination of pectin gelling mechanism using degree of esterification (DE is also focused in this research. In this study, oven drying with temperature 50°C was chosen as the best drying temperature due to highest extraction yield. Furthermore, Page-Two-term model was selected as the best model to describe the drying kinetics of banana peels due to highest R2 value (0.9991 and lowest RMSE value (0.001. The optimal extraction conditions given by BBD were 75°C extraction temperature, 23 min extraction time and 1:33.3 g/ml solid-liquid ratio. Likewise, the DE for both pectins extracted using unoptimised and optimised conditions were 71.92±1.38% and 76.1±2.07% respectively. Both of the pectins were classified as high-methoxyl pectins. The pectin with higher DE also indicated that the rate of gel formation is higher. The results showed that the pectin yield and gelling time has successfully improved after optimised the pectin extraction process.

Dynamic Modeling of Pectin Extraction for Monitoring and Optimisation

DEFF Research Database (Denmark)

Andersen, Nina M.; Santacoloma, Paloma A.; Gernaey, Krist

Pectin is used as an additive in many food and pharmaceutical products to modify the rheological properties of the product [1]. Commercial pectin extraction is a batch operation with several tanks that can feed continuously the downstream processing.The variability of the raw material is a contin...

Descriptive parameters for revealing substitution patterns of sugar beet pectins using pectolytic enzymes.

Science.gov (United States)

Remoroza, C; Buchholt, H C; Gruppen, H; Schols, H A

2014-01-30

Enzymatic fingerprinting was applied to sugar beet pectins (SBPs) modified by either plant or fungal pectin methyl esterases and alkali catalyzed de-esterification to reveal the ester distributions over the pectin backbone. A simultaneous pectin lyase (PL) treatment to the commonly used endo-polygalacturonase (endo-PG) degradation showed to be effective in degrading both high and low methylesterified and/or acetylated homogalaturonan regions of SBP simultaneously. Using LC-HILIC-MS/ELSD, we studied in detail all the diagnostic oligomers present, enabling us to discriminate between differently prepared sugar beet pectins having various levels of methylesterification and acetylation. Furthermore, distinction between commercially extracted and de-esterified sugar beet pectin having different patterns of substitution was achieved by using novel descriptive pectin parameters. In addition to DBabs approach for nonmethylesterified sequences degradable by endo-PG, the "degree of hydrolysis" (DHPG) representing all partially saturated methylesterified and/or acetylated galacturonic acid (GalA) moieties was introduced as a new parameter. Consequently, the description DHPL has been introduced to quantify all esterified unsaturated GalA oligomers. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sugar-cane juice induces pectin lyase and polygalacturonase in Penicillium griseoroseum

Directory of Open Access Journals (Sweden)

Minussi Rosana Cristina

1998-01-01

Full Text Available The use of other inducers as substitutes for pectin was studied aiming to reduce the production costs of pectic enzymes. The effects of sugar-cane juice on the production of pectin lyase (PL and polygalacturonase (PG by Penicillium griseoroseum were investigated. The fungus was cultured in a mineral medium (pH 6.3 in a rotary shaker (150 rpm for 48 h at 25oC. Culture media were supplemented with yeast extract and sucrose or sugar-cane juice. Sugar-cane juice added singly to the medium promoted higher PL activity and mycelial dry weight when compared to pectin and the use of sugar-cane juice and yeast extract yielded levels of PG activity that were similar to those obtained with sucrose-yeast extract or pectin. The results indicated that, even at low concentrations, sugar-cane juice was capable of inducing pectin lyase and polygalacturonase with no cellulase activity in P. griseoroseum.

Removal of the metal ions from aqueous solutions by nanoscaled low molecular pectin isolated from seagrass Phyllospadix iwatensis

International Nuclear Information System (INIS)

Khozhaenko, Elena; Kovalev, Valeri; Podkorytova, Elena; Khotimchenko, Maksim

2016-01-01

Pectins from sea grasses are considered as promising substances with pronounced metal-binding activity. Due to the high molecular weight and heterogeneous structure, the use of pectins for removal of metal ions is difficult. Technology of directed pectin degradation was developed and homogenous degraded nanoscaled pectin polymers were synthesized. Experimental samples of degraded pectin isolated from Phyllospadix iwatensis were tested for their metal binding activity in comparison with native pectin from this seagrass and commercial citrus pectin. The metal uptake of all pectin compounds was highest within the pH range from 4.0 to 6.0. The Langmuir, Freundlich and BET sorption models were applied to describe the isotherms and constants. Results showed that depolymerized pectin exerts highest lead and cadmium binding activity with pronounced affinity. All pectin compounds were suggested to be favorable sorbents. Therefore, it can be concluded that degraded pectin is a prospective material for creation of metal-removing water treatment systems. - Highlights: • Low molecular nanoscaled pectin was obtained using original hydrolysis method • Metal binding activity of pectin compounds was studied in a batch sorption system • Pectins exert highest metal binding activity at pH 6.0 • Metal binding isotherms of all pectins are best described by the Langmuir equation • Low molecular pectin from seagrasses is more effective than high-molecular pectins

Removal of the metal ions from aqueous solutions by nanoscaled low molecular pectin isolated from seagrass Phyllospadix iwatensis

Energy Technology Data Exchange (ETDEWEB)

Khozhaenko, Elena [Far Eastern Federal University, School of Biomedicine, 8, Sukhanova str., Vladivostok 690091 (Russian Federation); A.V. Zhirmunsky Institute of Marine Biology Far Eastern Branch of Russian Academy of Sciences, 17, Palchevskgo str., Vladivostok 690059 (Russian Federation); Kovalev, Valeri; Podkorytova, Elena [A.V. Zhirmunsky Institute of Marine Biology Far Eastern Branch of Russian Academy of Sciences, 17, Palchevskgo str., Vladivostok 690059 (Russian Federation); Khotimchenko, Maksim, E-mail: maxkhot@yandex.ru [Far Eastern Federal University, School of Biomedicine, 8, Sukhanova str., Vladivostok 690091 (Russian Federation); A.V. Zhirmunsky Institute of Marine Biology Far Eastern Branch of Russian Academy of Sciences, 17, Palchevskgo str., Vladivostok 690059 (Russian Federation)

2016-09-15

Pectins from sea grasses are considered as promising substances with pronounced metal-binding activity. Due to the high molecular weight and heterogeneous structure, the use of pectins for removal of metal ions is difficult. Technology of directed pectin degradation was developed and homogenous degraded nanoscaled pectin polymers were synthesized. Experimental samples of degraded pectin isolated from Phyllospadix iwatensis were tested for their metal binding activity in comparison with native pectin from this seagrass and commercial citrus pectin. The metal uptake of all pectin compounds was highest within the pH range from 4.0 to 6.0. The Langmuir, Freundlich and BET sorption models were applied to describe the isotherms and constants. Results showed that depolymerized pectin exerts highest lead and cadmium binding activity with pronounced affinity. All pectin compounds were suggested to be favorable sorbents. Therefore, it can be concluded that degraded pectin is a prospective material for creation of metal-removing water treatment systems. - Highlights: • Low molecular nanoscaled pectin was obtained using original hydrolysis method • Metal binding activity of pectin compounds was studied in a batch sorption system • Pectins exert highest metal binding activity at pH 6.0 • Metal binding isotherms of all pectins are best described by the Langmuir equation • Low molecular pectin from seagrasses is more effective than high-molecular pectins.

The pectin content in different types of fruit crops and their physicochemical characteristics

Directory of Open Access Journals (Sweden)

D. R. Sozaeva

2016-01-01

Full Text Available Currently pectin is widely used in food industry, pharmaceutical industry, medicine, and other industries due to its ability to form gels of different strength, and to having curative and preventive characteristics. Kabardino-Balkaria is one of the regions with industrial amounts of fruits, rich in pectin substances. In order to select the most promising raw materials for commercial production of pectin in the fruit of zoning in the territory of the Republic was determined the content of pectin substances and their physico-chemical parameters in the varieties of apples (Idared, Granny Smith, Florina, pears (Clapp Favorite, Talgar beauty, apricots (Ruddy, Salah, plums (Stanley, Kabardian early. It was established that the greatest number of pectin substances among varieties of apples is allocated in apples in Granny Smith sort, in pears in Clapp Favorite, in plums in Stanley, and in apricots in Salah sort: 1,14, 0,98, 1,03, 0.71% in the raw substance, respectively. It was found that pectin from apples, plums, apricots and pears with the exception of Clapp Favorite is highly etherified. The degree of methoxylation of pectin from apples varies between 70.71–81.85%, plums – from 60.99 to 67.31%, apricots – from 63.72 to 68.25%, from the pear Talgar beauty – 56.0%. Pectin from apples Granny Smith has the highest value of the degree of etherification. A high degree of etherification of pectin in this sort of apples can be recommended as thickening agents in different branches of food industry. Pectin from pears Clapp Favorite has low degree of etherification – 40.7%, that shows the evidence of their possible use in the manufacture of therapeutic and prophylactic purposes. According to the planned program of intensive horticulture in the region, by 2020 the area of Apple orchards will be up to 15 thousand hectares, and the harvest – up to a million tons. Taking that fact and the obtained experimental data into account, we assume that apples

Studies on pectin lyase

NARCIS (Netherlands)

Houdenhoven, van F.E.A.

1975-01-01

The pectin lyase activity in the commercial enzyme preparation Ultrazym originates from more then one type of enzyme; two of them, accounting for 95 % of the total activity, have been completely purified. As purity criteria specific activity, polyacrylamide disc gel electrophoresis and SDS

Pectin extraction from Citron peel (Citrus medica Linn. and its use in food system

Directory of Open Access Journals (Sweden)

Rojanakorn, T.

2006-11-01

Full Text Available Screening experiments using 25-1 fractional factorial design showed that pH, temperature, and extracting time were the main factors affecting the amount and quality of extracted pectin from Citrus medica Linn. Optimum condition of pectin extraction was studied using central composite design (CCD. Mathematical models relating pH, temperature and extracted time to amount of extracted pectin, equivalent weight, methyl content and anhydrogalacturonic acid content were established. Based on the mathematics models, the condition of pH 2, 100ºC and 105 min was found to be the optimum conditions for pectin extraction from Citrus medica Linn. Mathematical and experimental results were verified. The use of extracted pectin as a gelling agent in pineapple jam revealed no significant difference in gel consistency compared to that of commercial pectin grade 150 (p>0.05. However, the commercial pectin had a higher liking score on the spreadability, texture and overall liking. As a stabilizer in chocolate pasteurised milk, 0.2% of the extracted pectin was required to prevent precipitation of chocolate powder with the similar viscosity obtained from 0.06% κ-carageenan

Orange pectin mediated growth and stability of aqueous gold and silver nanocolloids

Science.gov (United States)

Nigoghossian, Karina; dos Santos, Molíria V.; Barud, Hernane S.; da Silva, Robson R.; Rocha, Lucas A.; Caiut, José M. A.; de Assunção, Rosana M. N.; Spanhel, Lubomir; Poulain, Marcel; Messaddeq, Younes; Ribeiro, Sidney J. L.

2015-06-01

The role of orange based pectin in the nucleation and growth of silver and gold nanoparticles is addressed. Pectin is a complex polysaccharide found in fruits such as oranges, lemons, passion fruits or apples. It displays smooth and hairy chain regions containing hydroxyl-, ester-, carboxylate- and eventually amine groups that can act as surface ligands interacting under various pH conditions more or less efficiently with growing nanometals. Here, a high methoxy pectin (>50% esterified) was used as a stabilizer/reducing agent in the preparation of gold, silver and silver-gold nanoparticles. Commercial pectin (CP) and pectin extracted from orange bagasse (OP) were used. Optionally, trisodium citrate or oxalic acid we used to reduce AgNO3 and HAuCl4 in aqueous environment. Characterization methods included UV-vis absorption spectroscopy, transmission electron microscopy, electron diffraction and energy-dispersive X-ray spectroscopy. The results show that under different pH conditions, pectin and reducing agents allow producing various nanostructures shapes (triangles, spheres, rods, octahedrons and decahedrons) often with high polydispersity and sizes ranging between 5 nm and 30 nm. In addition, depending on Ag/Au-ratio and pH, the surface plasmon bands can be continuously shifted between 410 nm and 600 nm. Finally, pectin seems to be a highly efficient stabilizer of the colloidal systems that show a remarkable stability and unchanged optical spectral response even after five years.

Extraction and Characterization of Pectin from Dragon Fruit (Hylocereus Polyrhizus) using Various Extraction Conditions

International Nuclear Information System (INIS)

Norazelina Sah Mohd Ismail; Nazaruddin Ramli; Norziah Mohd Hani; Zainudin Meon

2012-01-01

The extraction of pectin from dragon fruit (Hylocereus polyrhizus) peels under three different extraction conditions was identified as an alternative source of commercial pectin. In this work, dried alcohol-insoluble residues (AIR) of dragon fruit peels were treated separately with 0.25 % ammonium oxalate/oxalic acid at a pH of 4.6 at 85 degree Celsius; 0.03 M HCl at a pH of 1.5 at 85 degree Celsius; and de-ionized water at 75 degree Celsius. The pectin obtained from these methods was compared in terms of yield, physicochemical properties and chemical structure. Fourier Transform Infrared Spectroscopy (FTIR) was used in the identification of dragon fruit pectins. The results showed that the pectin yield (14.96-20.14 % based on dry weight), moisture content (11.13-11.33 %), ash content (6.88-11.55 %), equivalent weight (475.64-713.99), methoxyl content (2.98-4.34 %), anhydro uronic acid (45.25-52.45 %) and the degree of esterification (31.05-46.96 %) varied significantly (p < 0.05) with the various extraction conditions used. Pectin extracted with ammonium oxalate gave the highest yield of pectin, with high purity and low ash content. Based on the value of methoxyl content and the degree of esterification, dragon fruit pectin can be categorized as low-methoxyl pectin. (author)

Cloned Erwinia chrysanthemi out genes enable Escherichia coli to selectively secrete a diverse family of heterologous proteins to its milieu.

OpenAIRE

He, S Y; Lindeberg, M; Chatterjee, A K; Collmer, A

1991-01-01

The out genes of the enterobacterial plant pathogen Erwinia chrysanthemi are responsible for the efficient extracellular secretion of multiple plant cell wall-degrading enzymes, including four isozymes of pectate lyase, exo-poly-alpha-D-galacturonosidase, pectin methylesterase, and cellulase. Out- mutants of Er. chrysanthemi are unable to export any of these proteins beyond the periplasm and are severely reduced in virulence. We have cloned out genes from Er. chrysanthemi in the stable, low-c...

Ionic gelation of low-esterification degree pectins from immature thinned apples

OpenAIRE

Rascón-Chu, Agustín; Martínez-López, Ana-Luisa; Carvajal-Millán, Elizabeth; Martínez-Robinson, Karla G.; Campa-Mada, Alma C.

2016-01-01

Fruit thinning is a regular practice in apple (Malus x domestica Borkh.) orchards to increase fruit size and to promote blooming. This practice generates immature, small (10 to 40 mm diameter) fruits, which are occasionally used as cattle feed. The use of thinned apples for pectin extraction could increase orchards profitability and promote development of new transformation processes. Pectin is a polysaccharide located on the cell wall of plant tissues. Commercial pectins are extracted from d...

Extraction, characterisation, and enzymatic degradation of lemon peel pectins.

NARCIS (Netherlands)

Ros, J.M.; Schols, H.A.; Voragen, A.G.J.

1996-01-01

The albedo of Spanish lemons (16.0% w/w of lemon fresh weight) was extracted to obtain a chelating agent soluble pectin fraction, a diluted sodium hydroxide soluble pectin fraction and a residue (4.2, 1.8, and 5.0% w/w of fresh albedo, respectively). These fractions represented 61.3, 12.4, and 10.4%

Composite films from pectin and fish skin gelatin or soybean flour protein.

Science.gov (United States)

Liu, LinShu; Liu, Cheng-Kung; Fishman, Marshall L; Hicks, Kevin B

2007-03-21

Composite films were prepared from pectin and fish skin gelatin (FSG) or pectin and soybean flour protein (SFP). The inclusion of protein promoted molecular interactions, resulting in a well-organized homogeneous structure, as revealed by scanning electron microscopy and fracture-acoustic emission analysis. The resultant composite films showed an increase in stiffness and strength and a decrease in water solubility and water vapor transmission rate, in comparison with films cast from pectin alone. The composite films inherited the elastic nature of proteins, thus being more flexible than the pure pectin films. Treating the composite films with glutaraldehyde/methanol induced chemical cross-linking with the proteins and reduced the interstitial spaces among the macromolecules and, consequently, improved their mechanical properties and water resistance. Treating the protein-free pectin films with glutaraldehyde/methanol also improved the Young's modulus and tensile strength, but showed little effect on the water resistance, because the treatment caused only dehydration of the pectin films and the dehydration is reversible. The composite films were biodegradable and possessed moderate mechanical properties and a low water vapor transmission rate. Therefore, the films are considered to have potential applications as packaging or coating materials for food or drug industries.

Low-Temperature Blanching as a Tool to Modulate the Structure of Pectin in Blueberry Purees.

Science.gov (United States)

Chevalier, Laura M; Rioux, Laurie-Eve; Angers, Paul; Turgeon, Sylvie L

2017-09-01

Blueberry composition was characterized for 6 cultivars. It contains a good amount of dietary fiber (10% to 20%) and pectin (4% to 7%) whose degree of methylation (DM) is sensitive to food processing. A low temperature blanching (LTB: 60 °C/1 h) was applied on blueberry purees to decrease pectin DM, in order to modulate puree properties and functionalities (that is, viscosity and stability), and to enhance pectin affinity toward other components within food matrices. Fiber content, viscosity, pectin solubility, DM, and monosaccharide composition were determined for both pasteurized, and LTB+pasteurized blueberry purees. The results showed that neither the amount of fiber, nor the viscosity were affected by LTB, indicating that this treatment did not result in any significant pectin depolymerization and degradation. LTB caused a decrease both in pectin DM from 58-67% to 45-47% and in the amount of water-soluble pectin fraction, the latter remaining the major fraction of total pectin at 52% to 57%. A LTB is a simple and mild process to produce blueberry purees with mostly soluble and low-methylated pectin in order to extend functionality and opportunities for interactions with other food ingredients. © 2017 Institute of Food Technologists®.

Preparation of pectin/silver nanoparticles composite films with UV-light barrier and properties.

Science.gov (United States)

Shankar, Shiv; Tanomrod, Nattareya; Rawdkuen, Saroat; Rhim, Jong-Whan

2016-11-01

Silver nanoparticles (AgNPs) was synthesized by a green method using an aqueous extract of Caesalpinia mimosoides Lamk (CMLE) as reducing and stabilizing agents, and they were used for the preparation of pectin-based antimicrobial composite films. The AgNPs were spherical in shape with the size in the range of 20-80nm and showed the absorption peak around 500nm. The pectin/AgNPs composite film exhibited characteristic absorption peak of AgNPs at 480nm. The surface color and light transmittance of the pectin films were greatly influenced by the addition of AgNPs. The lightness of the films decreased, however, redness and yellowness of the films increased after incorporation of AgNPs. UV-light barrier property of the pectin film increased significantly with a little decrease in the transparency. Though there were no structural changes in the pectin film by the incorporation of CMLE and AgNPs as indicated by the FTIR results, the film properties such as thermal stability, mechanical strength, and water vapor barrier properties of the pectin films increased. The pectin/AgNPs nanocomposite films exhibited strong antibacterial activity against food-borne pathogenic bacteria, Escherichia coli and Listeria monocytogenes. Copyright © 2016 Elsevier B.V. All rights reserved.

Modification of citrus and apple pectin by power ultrasound: Effects of acid and enzymatic treatment.

Science.gov (United States)

Muñoz-Almagro, Nerea; Montilla, Antonia; Moreno, F Javier; Villamiel, Mar

2017-09-01

Pectin-derived oligosaccharides are emerging as a new generation of functional ingredients with new or improved technological and/or bioactive properties as compared to pectin. This work addresses the impact of power ultrasound (US) on the structure of citrus and apple pectin under different experimental conditions of power, amplitude and pectin concentration in aqueous and acid media, as well as in the presence of a pectinase. Results indicated that depolymerisation of both pectin increased with time and intensity of US in aqueous media and their polydispersity decreased. In general, a higher depolymerisation was observed in pectin treated by US in the presence of nitric and citric acids than in water, and hardly any difference was detected between both types of acids. Most of the assays gave rise to high-methoxylated pectin with a degree of esterification above 50%, pointing out their suitability for potential gelling agents. Finally, US did not have any impact in assisted enzymatic hydrolysis on the degree and/or rate of depolymerisation at low and medium levels of pectin concentration (0.5 and 2%), whereas a higher diversity of pectin fragments was found at 5% which could be indicative of a more controlled depolymerisation. These findings highlight the importance of the selection of appropriate US processing conditions to diversify the applications of modified pectin, as well as the potential of US as a prospective alternative to currently used depolymerisation techniques. Copyright © 2016 Elsevier B.V. All rights reserved.

HIGHLY METHYL ESTERIFIED SEEDS is a pectin methyl esterase involved in embryo development.

Science.gov (United States)

Levesque-Tremblay, Gabriel; Müller, Kerstin; Mansfield, Shawn D; Haughn, George W

2015-03-01

Homogalacturonan pectin domains are synthesized in a highly methyl-esterified form that later can be differentially demethyl esterified by pectin methyl esterase (PME) to strengthen or loosen plant cell walls that contain pectin, including seed coat mucilage, a specialized secondary cell wall of seed coat epidermal cells. As a means to identify the active PMEs in seed coat mucilage, we identified seven PMEs expressed during seed coat development. One of these, HIGHLY METHYL ESTERIFIED SEEDS (HMS), is abundant during mucilage secretion, peaking at 7 d postanthesis in both the seed coat and the embryo. We have determined that this gene is required for normal levels of PME activity and homogalacturonan methyl esterification in the seed. The hms-1 mutant displays altered embryo morphology and mucilage extrusion, both of which are a consequence of defects in embryo development. A significant decrease in the size of cells in the embryo suggests that the changes in embryo morphology are a consequence of lack of cell expansion. Progeny from a cross between hms-1 and the previously characterized PME inhibitor5 overexpression line suggest that HMS acts independently from other cell wall-modifying enzymes in the embryo. We propose that HMS is required for cell wall loosening in the embryo to facilitate cell expansion during the accumulation of storage reserves and that its role in the seed coat is masked by redundancy. © 2015 American Society of Plant Biologists. All Rights Reserved.

Formation of nano-hydroxyapatite crystal in situ in chitosan-pectin polyelectrolyte complex network

International Nuclear Information System (INIS)

Li Junjie; Zhu Dunwan; Yin Jianwei; Liu Yuxi; Yao Fanglian; Yao Kangde

2010-01-01

Hydroxyapatite (HA)/polysaccharide composites have been widely used in bone tissue engineering due to their chemical similarity to natural bone. Polymer matrix-mediated synthesis of nano-hydroxyapatite is one of the simplest models for biomimetic. In this article, the nano-hydroxyapatite/chitosan-pectin (nHCP) composites were prepared through in situ mineralization of hydroxyapatite in chitosan-pectin polyelectrolyte complex (PEC) network. The formation processes of nHCP were investigated by X-ray diffraction (XRD) analysis. The interactions between nHA crystal and chitosan-pectin PEC networks were studied using Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). The morphology and structure of nHA crystal were characterized by XRD and Transmission Electron Microscope (TEM). Results suggested that the interfacial interactions between nano-hydroxyapatite crystal and chitosan-pectin PEC network assist the site specific nucleation and growth of nHA nanoparticles. The nHA crystals grow along the c-axis. In this process, pH value is the main factor to control the nucleation and growth of nHA crystal in chitosan-pectin PEC networks, because both the interactions' strength between nHA crystal and chitosan-pectin and diffusion rate of inorganic ions depend on the pH value of the reaction system. Apart from the pH value, the chitosan/pectin ratio and [Ca 2+ ] also take important effects on the formation of nHA crystal. An effective way to control the size of nHA crystal is to adjust the content of pectin and [Ca 2+ ]. It is interesting that the Zeta potential of nHCP composites is about - 30 mV when the chitosan/pectin ratio ≤ 1:1, and the dispersion solution of nHCP composites has higher stability, which provides the possibility to prepare 3D porous scaffolds with nHCP for bone tissue engineering.

Formation of nano-hydroxyapatite crystal in situ in chitosan-pectin polyelectrolyte complex network

Energy Technology Data Exchange (ETDEWEB)

Li Junjie [Department of Polymer Science and Key Laboratory of Systems Bioengineering of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072 (China); Research Institute of Polymeric Materials, Tianjin University, Tianjin, 300072 (China); Zhu Dunwan [Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, 300072 (China); Yin Jianwei; Liu Yuxi [Department of Polymer Science and Key Laboratory of Systems Bioengineering of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072 (China); Yao Fanglian, E-mail: yaofanglian@tju.edu.cn [Department of Polymer Science and Key Laboratory of Systems Bioengineering of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072 (China); Yao Kangde [Research Institute of Polymeric Materials, Tianjin University, Tianjin, 300072 (China)

2010-07-20

Hydroxyapatite (HA)/polysaccharide composites have been widely used in bone tissue engineering due to their chemical similarity to natural bone. Polymer matrix-mediated synthesis of nano-hydroxyapatite is one of the simplest models for biomimetic. In this article, the nano-hydroxyapatite/chitosan-pectin (nHCP) composites were prepared through in situ mineralization of hydroxyapatite in chitosan-pectin polyelectrolyte complex (PEC) network. The formation processes of nHCP were investigated by X-ray diffraction (XRD) analysis. The interactions between nHA crystal and chitosan-pectin PEC networks were studied using Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). The morphology and structure of nHA crystal were characterized by XRD and Transmission Electron Microscope (TEM). Results suggested that the interfacial interactions between nano-hydroxyapatite crystal and chitosan-pectin PEC network assist the site specific nucleation and growth of nHA nanoparticles. The nHA crystals grow along the c-axis. In this process, pH value is the main factor to control the nucleation and growth of nHA crystal in chitosan-pectin PEC networks, because both the interactions' strength between nHA crystal and chitosan-pectin and diffusion rate of inorganic ions depend on the pH value of the reaction system. Apart from the pH value, the chitosan/pectin ratio and [Ca{sup 2+}] also take important effects on the formation of nHA crystal. An effective way to control the size of nHA crystal is to adjust the content of pectin and [Ca{sup 2+}]. It is interesting that the Zeta potential of nHCP composites is about - 30 mV when the chitosan/pectin ratio {<=} 1:1, and the dispersion solution of nHCP composites has higher stability, which provides the possibility to prepare 3D porous scaffolds with nHCP for bone tissue engineering.

Pectins from the albedo of immature lemon fruitlets have high water binding capacity.

Science.gov (United States)

Schröder, Roswitha; Clark, Christopher J; Sharrock, Keith; Hallett, Ian C; MacRae, Elspeth A

2004-04-01

The white part of citrus peel, the albedo, has a special role in water relations of both fruit and leaves from early on in fruit development. In times of drought, this tissue acts as a water reservoir for juice sacs, seeds and leaves. When water was injected into the albedo, free water was undetectable using magnetic resonance imaging. Microscopy showed tightly packed cells with little intercellular space, and thick cell walls. Cell wall material comprised 21% of the fresh albedo weight, and contained 26.1% galacturonic acid, the main constituent of pectin. From this, we postulated that pectin of the cell wall was responsible for the high water-binding capacity of the immature lemon albedo. Cell wall material was extracted using mild procedures that keep polymers intact, and four pectic fractions were recovered. Of these fractions, the SDS and chelator-soluble fractions showed viscosities ten and twenty times higher than laboratory-grade citrus pectin or the other albedo-derived pectins. The yield of these two pectins represented 28% of the cell walls and 62% of the galacturonic acid content of immature lemon albedo. We concluded that, from viscosity and abundance, these types of pectin account for the high water-binding capacity of this tissue. Compositional analyses showed that the two highly viscous pectic fractions differ in galacturonic acid content, degree of branching and length of side chains from the less viscous albedo-derived pectins. The most striking feature of these highly viscous pectins, however, was their high molecular weight distribution compared to the other pectic fractions.

We be jammin’: an update on pectin biosynthesis, trafficking and dynamics

Energy Technology Data Exchange (ETDEWEB)

Anderson, Charles T.

2015-11-20

Pectins are complex polysaccharides that contain acidic sugars and are major determinants of the cohesion, adhesion, extensibility, porosity and electrostatic potential of plant cell walls. Recent evidence has solidified their positions as key regulators of cellular growth and tissue morphogenesis, although important details of how they achieve this regulation are still missing. Pectins are also hypothesized to function as ligands for wall integrity sensors that enable plant cells to respond to intrinsic defects in wall biomechanics and to wall degradation by attacking pathogens. This update highlights recent advances in our understanding of the biosynthesis of pectins, how they are delivered to the cell surface and become incorporated into the cell wall matrix and how pectins are modified over time in the apoplast. It also poses unanswered questions for further research into this enigmatic but essential class of carbohydrate polymers.

Pectin engineering to modify product quality in potato.

Science.gov (United States)

Ross, Heather A; Morris, Wayne L; Ducreux, Laurence J M; Hancock, Robert D; Verrall, Susan R; Morris, Jenny A; Tucker, Gregory A; Stewart, Derek; Hedley, Pete E; McDougall, Gordon J; Taylor, Mark A

2011-10-01

Although processed potato tuber texture is an important trait that influences consumer preference, a detailed understanding of tuber textural properties at the molecular level is lacking. Previous work has identified tuber pectin methyl esterase (PME) activity as a potential factor impacting on textural properties, and the expression of a gene encoding an isoform of PME (PEST1) was associated with cooked tuber textural properties. In this study, a transgenic approach was undertaken to investigate further the impact of the PEST1 gene. Antisense and over-expressing potato lines were generated. In over-expressing lines, tuber PME activity was enhanced by up to 2.3-fold; whereas in antisense lines, PME activity was decreased by up to 62%. PME isoform analysis indicated that the PEST1 gene encoded one isoform of PME. Analysis of cell walls from tubers from the over-expressing lines indicated that the changes in PME activity resulted in a decrease in pectin methylation. Analysis of processed tuber texture demonstrated that the reduced level of pectin methylation in the over-expressing transgenic lines was associated with a firmer processed texture. Thus, there is a clear link between PME activity, pectin methylation and processed tuber textural properties. © 2011 The Authors. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

INTERACTION OF NIZKOMETILIROVANNYJ PECTINS WITH A CONCENTRATE OF PROTEINS OF WHEY

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H. I. Teshaev

2012-01-01

Full Text Available Potentiometric titration method was used to study quality complex formation between low methylated pectin and proteins concentrated from whey. It’s shown that at рН>IEP of the lactoglobulin the interaction occurs between negatively charged chains of LM-pectin and positively charged patches of polypeptide chains. The biopolymers ratio had no significant effect on the initial pH of soluble complex formation (pHc; addition of sodium chloride decreased pHc and pK0 of complexes, which linked to electrostatic nature of complex formation between LM-pectin and whey proteins.

Food emulsions with amidated pectin from celery (Apium graveolens var. rapaceum D.C. tubers

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Iv. Petrova

2017-09-01

Full Text Available Abstract. Hydrocolloids, especially polysaccharides from traditional plant sources and their derivatives possessed significant emulsifying properties. Pectin was isolated from celery tubers by accelerated “green” method for extraction based on ultrasonic irradiation. Further chemical modification of celery pectin was performed with 4 mol/L NH The amidated celery pectin was obtained with the following characteristics: the degree of esterification (DE 31%, the degree of 3. amidation (DA 16%, degree of acetylation (DAc 2% and anhydrouronic acid content (AUAC 68%. This modified pectin was incorporated in preparation of model 30, 40 and 50% oil-in-water emulsions. The effect of amidation of celery pectin on the stability of emulsions was investigated. The results showed that amidation increased the emulsifying properties of pectic polysaccharides. It affected also the rheological characteristics of model emulsion. The current study demonstrated preparation of emulsion with low-caloric amidated pectin as proper alternative to the traditional emulsifiers.

Antioxidant activity and emulsion-stabilizing effect of pectic enzyme treated pectin in soy protein isolate-stabilized oil/water emulsion.

Science.gov (United States)

Huang, Ping-Hsiu; Lu, Hao-Te; Wang, Yuh-Tai; Wu, Ming-Chang

2011-09-14

The antioxidant activity of pectic enzyme treated pectin (PET-pectin) prepared from citrus pectin by enzymatic hydrolysis and its potential use as a stabilizer and an antioxidant for soy protein isolate (SPI)-stabilized oil in water (O/W) emulsion were investigated. Trolox equivalent antioxidant capacity (TEAC) was found to be positively associated with molecular weight (M(w)) of PET-pectin and negatively associated with degree of esterification (DE) of PET-pectin. PET-pectin (1 kDa and 11.6% DE) prepared from citrus pectin after 24 h of hydrolysis by commercial pectic enzyme produced by Aspergillus niger expressed higher α,α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity, TEAC, and reducing power than untreated citrus pectin (353 kDa and 60% DE). The addition of PET-pectin could increase both emulsifying activity (EA) and emulsion stability (ES) of SPI-stabilized O/W emulsion. When the SPI-stabilized lipid droplet was coated with the mixture of PET-pectin and pectin, the EA and ES of the emulsion were improved more than they were when the lipid droplet was coated with either pectin or PET-pectin alone. The amount of secondary oxidation products (thiobarbituric acid reactive substances) produced in the emulsion prepared with the mixture of SPI and PET-pectin was less than the amount produced in the emulsion prepared with either SPI or SPI/pectin. These results suggest that PET-pectin has an emulsion-stabilizing effect and lipid oxidation inhibition ability on SPI-stabilized emulsion. Therefore, PET-pectin can be used as a stabilizer as well as an antioxidant in plant origin in SPI-stabilized O/W emulsion and thus prolong the shelf life of food emulsion.

Detoxical aspects of nutritional therapy using natural enterosorbents on the basis of pectins

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Elena E. Tekutskaya

2013-09-01

Full Text Available The rate of anthropogenic pollution and reduction of the environmental quality progress quicker than adaptive possibilities of an organism. This causes pre-pathological and pathological changes. So there is a necessity of preventive measures organization to eliminate toxic load and accelerated eliminating of xenobiotics from an organism. The discoveries of the recent 15 years had been revealed the possibility to change complexons (which are used for detoxication to dietary fibers, pectin as well. Meanwhile pectin substances are not widely used in clinical practice, and their efficiency comparing with small concentrations of cumulating poisons had not been studied yet. During the development of the detoxification nutritional therapy at patients with different pathology of the digestive system organs (with the revealed heavy metals and organochlorine pesticides there had been organized tests of pectin efficiency (citrus and apple for reducing the contamination with these xenobiotics. After the course of pectin treatment there had been fixed not only the reduce of toxic heavy metals, but essential microelements as well, which is connected with nonselective complexing capability of pectin substances. The probe tests also showed that course of citrus pectin treatment favored total excretion of organochlorine pesticides at 11.0% of patients, at other patients pesticide level reduced up to minimal rate (revealed by gas chromatographic method 0.0001 mg/dm³. There is a significant difference of values before and after pectin treatment. At the same time at patients who had not taken enterosorbent (compare group the level of organochlorine pesticides after repeated tests stayed on the level close to the basic. There had been discussed mechanism of excretion of organochlorine pesticides and heavy metals with the help of pectins.

Combinatorial control of gene expression in Aspergillus niger grown on sugar beet pectin.

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Kowalczyk, Joanna E; Lubbers, Ronnie J M; Peng, Mao; Battaglia, Evy; Visser, Jaap; de Vries, Ronald P

2017-09-27

Aspergillus niger produces an arsenal of extracellular enzymes that allow synergistic degradation of plant biomass found in its environment. Pectin is a heteropolymer abundantly present in the primary cell wall of plants. The complex structure of pectin requires multiple enzymes to act together. Production of pectinolytic enzymes in A. niger is highly regulated, which allows flexible and efficient capture of nutrients. So far, three transcriptional activators have been linked to regulation of pectin degradation in A. niger. The L-rhamnose-responsive regulator RhaR controls the production of enzymes that degrade rhamnogalacturonan-I. The L-arabinose-responsive regulator AraR controls the production of enzymes that decompose the arabinan and arabinogalactan side chains of rhamnogalacturonan-II. The D-galacturonic acid-responsive regulator GaaR controls the production of enzymes that act on the polygalacturonic acid backbone of pectin. This project aims to better understand how RhaR, AraR and GaaR co-regulate pectin degradation. For that reason, we constructed single, double and triple disruptant strains of these regulators and analyzed their growth phenotype and pectinolytic gene expression in A. niger grown on sugar beet pectin.

Pectin-lipid self-assembly: influence on the formation of polyhydroxy fatty acids nanoparticles.

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Susana Guzman-Puyol

Full Text Available Nanoparticles, named cutinsomes, have been prepared from aleuritic (9,10,16-trihidroxipalmitic acid and tomato fruit cutin monomers (a mixture of mainly 9(10,16-dihydroxypalmitic acid (85%, w/w and 16-hydroxyhexadecanoic acid (7.5%, w/w with pectin in aqueous solution. The process of formation of the nanoparticles of aleuritic acid plus pectin has been monitored by UV-Vis spectrophotometry, while their chemical and morphological characterization was analyzed by ATR-FTIR, TEM, and non-contact AFM. The structure of these nanoparticles can be described as a lipid core with a pectin shell. Pectin facilitated the formation of nanoparticles, by inducing their aggregation in branched chains and favoring the condensation between lipid monomers. Also, pectin determined the self-assembly of cutinsomes on highly ordered pyrolytic graphite (HOPG surfaces, causing their opening and forming interconnected structures. In the case of cutin monomers, the nanoparticles are fused, and the condensation of the hydroxy fatty acids is strongly affected by the presence of the polysaccharide. The interaction of pectin with polyhydroxylated fatty acids could be related to an initial step in the formation of the plant biopolyester cutin.

Pectin-lipid self-assembly: influence on the formation of polyhydroxy fatty acids nanoparticles.

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Guzman-Puyol, Susana; Benítez, José Jesús; Domínguez, Eva; Bayer, Ilker Sefik; Cingolani, Roberto; Athanassiou, Athanassia; Heredia, Antonio; Heredia-Guerrero, José Alejandro

2015-01-01

Nanoparticles, named cutinsomes, have been prepared from aleuritic (9,10,16-trihidroxipalmitic) acid and tomato fruit cutin monomers (a mixture of mainly 9(10),16-dihydroxypalmitic acid (85%, w/w) and 16-hydroxyhexadecanoic acid (7.5%, w/w)) with pectin in aqueous solution. The process of formation of the nanoparticles of aleuritic acid plus pectin has been monitored by UV-Vis spectrophotometry, while their chemical and morphological characterization was analyzed by ATR-FTIR, TEM, and non-contact AFM. The structure of these nanoparticles can be described as a lipid core with a pectin shell. Pectin facilitated the formation of nanoparticles, by inducing their aggregation in branched chains and favoring the condensation between lipid monomers. Also, pectin determined the self-assembly of cutinsomes on highly ordered pyrolytic graphite (HOPG) surfaces, causing their opening and forming interconnected structures. In the case of cutin monomers, the nanoparticles are fused, and the condensation of the hydroxy fatty acids is strongly affected by the presence of the polysaccharide. The interaction of pectin with polyhydroxylated fatty acids could be related to an initial step in the formation of the plant biopolyester cutin.

Utilization of Aspergillus oryzae to produce pectin lyase from various agro-industrial residues

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Safia Koser

2014-07-01

Full Text Available The present study was aimed to investigate the culture influence on pectin lyase production potential of fungal strain Aspergillus oryzae. The enzyme profile of A. oryzae showed highest activity of pectin lyase after 3rd day of incubation on lemon peel waste under solid state fermentation conditions. To induce the pectin lyase synthesis capability of A. oryzae at optimal level various culture variables including physical and nutritional parameters were optimized by adopting classical optimization technique. Therefore, through fermentation process optimization the production of pectin lyase was substantially induced up to the level of 875 U/mL, when fermentation medium of lemon peel waste inoculated with 5 mL spore suspension of A. oryzae. The optimal fermentation conditions for maximum pectin lyase yield were as: optimum pH 5, 70% moisture level and incubated at 40 °C in addition with 1% sterile glucose solution as readily available carbon source and 0.2% yeast extract as an inexpensive nitrogen supplement (1%. The results obtained in current investigation so far demonstrated that culture conditions have great influence on the pectin lyase production potential of A. oryzae.

Formation of Polyelectrolyte Complex Colloid Particles between Chitosan and Pectin with Different Degree of Esterification

Science.gov (United States)

Wang, Hui; Sun, Hongyuan; He, Jieyu

2017-12-01

The effects of degree of esterification, pectin/chitosan ratio and pH on the formation of polyelectrolyte complex colloid particles between chitosan (CS) and pectin (PE) were investigated. Low methoxyl pectin (LPE) was achieved by de-esterifying high methoxyl pectin (HPE) with pectin methyl esterase. Turbidity titration and colorimetric method was used to determine the stability of complex colloid particles. The structure and morphology of complex particles were characterized by FTIR and TEM. When pectin solution was dropped into chitosan solution, complex colloidal dispersion was stable as PE/CS mass ratio was no more than 3:2. Colloidal particles of HPE-CS complex coagulated at larger ratio of PE/CS than LPE-CS. The maximum complex occurred at pH 6.1 for HPE-CS and pH 5.7 for LPE-CS, and decreasing pH leaded to the dissociation of complex particles. Electrostatic interactions between carboxyl groups on pectin and amino groups on chitosan were confirmed by FTIR. Colloidal particle sizes ranged from about 100 nm to 400 nm with spherical shape.

Combined HILIC-ELSD/ESI-MS(n) enables the separation, identification and quantification of sugar beet pectin derived oligomers.

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Remoroza, C; Cord-Landwehr, S; Leijdekkers, A G M; Moerschbacher, B M; Schols, H A; Gruppen, H

2012-09-01

The combined action of endo-polygalacturonase (endo-PGII), pectin lyase (PL), pectin methyl esterase (fungal PME) and RG-I degrading enzymes enabled the extended degradation of methylesterified and acetylated sugar beet pectins (SBPs). The released oligomers were separated, identified and quantified using hydrophilic interaction liquid chromatography (HILIC) with online electrospray ionization ion trap mass spectrometry (ESI-IT-MS(n)) and evaporative light scattering detection (ELSD). By MS(n), the structures of galacturonic acid (GalA) oligomers having an acetyl group in the O-2 and/or O-3 positions eluting from the HILIC column were elucidated. The presence of methylesterified and/or acetylated galacturonic acid units within an oligomer reduced the interaction with the HILIC column significantly compared to the unsubstituted GalA oligomers. The HILIC column enables a good separation of most oligomers present in the digest. The use of ELSD to quantify oligogalacturonides was validated using pure GalA standards and the signal was found to be independent of the chemical structure of the oligomer being detected. The combination of chromatographic and enzymatic strategies enables to distinguish SBPs having different methylesters and acetyl group distribution. Copyright © 2012 Elsevier Ltd. All rights reserved.

Characterization of microparticles prepared by emulsion method from pectin and protein

Science.gov (United States)

In this study, pectin was extracted from apple peel and formulated into microparticles in combination with zein, an edible food protein. The physical, chemical, and structural properties of the resultant pectin structures were evaluated. The resultant microparticles were also examined in vitro for c...

PaeX, a second pectin acetylesterase of Erwinia chrysanthemi 3937.

Science.gov (United States)

Shevchik, Vladimir E; Hugouvieux-Cotte-Pattat, Nicole

2003-05-01

Erwinia chrysanthemi causes soft-rot diseases of various plants by enzymatic degradation of the pectin in plant cell walls. Pectin is a complex polysaccharide. The main chain is constituted of galacturonate residues, and some of them are modified by methyl and/or acetyl esterification. Esterases are necessary to remove these modifications and, thus, to facilitate the further degradation of the polysaccharidic chain. In addition to PaeY, the first pectin acetylesterase identified in the E. chrysanthemi strain 3937, we showed that this bacterium produces a second pectin acetylesterase encoded by the gene paeX. The paeX open reading frame encodes a 322-residue precursor protein of 34,940 Da, including a 21-amino-acid signal peptide. Analysis of paeX transcription, by using gene fusions, revealed that it is induced by pectic catabolic products and affected by catabolite repression. The expression of paeX is regulated by the repressor KdgR, which controls all the steps of pectin catabolism; by the repressor PecS, which controls most of the pectinase genes; and by catabolite regulatory protein, the global activator of sugar catabolism. The paeX gene is situated in a cluster of genes involved in the catabolism and transport of pectic oligomers. In induced conditions, the two contiguous genes kdgM, encoding an oligogalacturonate-specific porin, and paeX are both transcribed as an operon from a promoter proximal to kdgM, but transcription of paeX can also be uncoupled from that of kdgM in noninduced conditions. PaeX is homologous to the C-terminal domain of the Butyrivibrio fibriosolvens xylanase XynB and to a few bacterial esterases. PaeX contains the typical box (GxSxG) corresponding to the active site of the large family of serine hydrolases. Purified PaeX releases acetate from various synthetic substrates and from sugar beet pectin. The PaeX activity increased after previous depolymerization and demethylation of pectin, indicating that its preferred substrates are

Physical and oxidative stability of fish oil-in-water emulsions stabilized with beta-lactoglobulin and pectin.

Science.gov (United States)

Katsuda, Marly S; McClements, D J; Miglioranza, Lucia H S; Decker, Eric A

2008-07-23

The oxidation of fatty acids can be inhibited by engineering the surface of oil-in-water emulsion droplets to decrease interactions between aqueous phase prooxidants and lipids. The objective of this research was to evaluate whether emulsions stabilized by a multilayer emulsifier systems consisting of beta-lactoglobulin and citrus or sugar beet pectin could produce fish oil-in-water emulsions that had good physical and oxidative stability. Sugar beet pectin was compared to citrus pectin because the sugar beet pectin contains the known antioxidant, ferulic acid. A primary Menhaden oil-in-water emulsion was prepared with beta-lactoglobulin upon which the pectins were electrostatically deposited at pH 3.5. Emulsions prepared with 1% oil, 0.05% beta-lactoglobulin, and 0.06% pectins were physically stable for up to 16 days. As determined by monitoring lipid hydroperoxide and headspace propanal formation, emulsions prepared with the multilayer system of beta-lactoglobulin and citrus pectin were more stable than emulsions stabilized with beta-lactoglobulin alone. Emulsions prepared with the multilayer system of beta-lactoglobulin and sugar beet pectin were less stable than emulsions stabilized with beta-lactoglobulin alone despite the presence of ferulic acid in the sugar beet pectin. The lower oxidative stability of the emulsions with the sugar beet pectin could be due to its higher iron and copper concentrations which would produce oxidative stress that would overcome the antioxidant capacity of ferulic acid. These data suggest that the oxidative stability of oil-in-water emulsions containing omega-3 fatty acids could be improved by the use of multilayer emulsion systems containing pectins with low metal concentrations.

Molecular Properties of Guar Gum and Pectin Modify Cecal Bile Acids, Microbiota, and Plasma Lipopolysaccharide-Binding Protein in Rats.

Science.gov (United States)

Ghaffarzadegan, Tannaz; Marungruang, Nittaya; Fåk, Frida; Nyman, Margareta

2016-01-01

Bile acids (BAs) act as signaling molecules in various physiological processes, and are related to colonic microbiota composition as well as to different types of dietary fat and fiber. This study investigated whether guar gum and pectin-two fibers with distinct functional characteristics-affect BA profiles, microbiota composition, and gut metabolites in rats. Low- (LM) or high-methoxylated (HM) pectin, and low-, medium-, or high-molecular-weight (MW) guar gum were administered to rats that were fed either low- or high-fat diets. Cecal BAs, short-chain fatty acids (SCFA) and microbiota composition, and plasma lipopolysaccharide-binding protein (LBP) levels were analyzed, by using novel methodologies based on gas chromatography (BAs and SCFAs) and 16S rRNA gene sequencing on the Illumina MiSeq platform. Strong correlations were observed between cecal BA and SCFA levels, microbiota composition, and portal plasma LBP levels in rats on a high-fat diet. Notably, guar gum consumption with medium-MW increased the cecal amounts of cholic-, chenodeoxycholic-, and ursodeoxycholic acids as well as α-, β-, and ω-muricholic acids to a greater extent than other types of guar gum or the fiber-free control diet. In contrast, the amounts of cecal deoxycholic- and hyodeoxycholic acid were reduced with all types of guar gum independent of chain length. Differences in BA composition between pectin groups were less obvious, but cecal levels of α- and ω-muricholic acids were higher in rats fed LM as compared to HM pectin or the control diet. The inflammatory marker LBP was downregulated in rats fed medium-MW guar gum and HM pectin; these two fibers decreased the cecal abundance of Oscillospira and an unclassified genus in Ruminococcaceae, and increased that of an unclassified family in RF32. These results indicate that the molecular properties of guar gum and pectin are important for their ability to modulate cecal BA formation, gut microbiota composition, and high-fat diet induced

Effect of Amidated Low Methoxyl Pectin on the Mechanical Properties and Colour Attributes of Fish Mince

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Rocio M. Uresti

2003-01-01

Full Text Available Pectins have been unsuccessfully applied to improve functionality of meat and fish products. Effect of amidated low methoxyl pectin (ALM pectin levels on functionality of Mexican flounder (Cyclopsetta chittendenii mince was studied. Changes in the firmness and work of extrusion of pastes, texture profile analysis (TPA of gels, and colour parameters were determined. ALM pectin at 1 % decreased firmness and work of extrusion of fish pastes but increased hardness, chewiness and cohesiveness of the gels (P<0.05. The addition of ALM pectin increased slightly the whiteness and yellowness of mince gels. Chrome parameter indicated that gels remained in the grayish achromatic region. Therefore ALM pectin at 1 % could be employed to modify the textural properties of fish mince.

Mapping sugar beet pectin acetylation pattern.

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Ralet, Marie-Christine; Cabrera, Juan Carlos; Bonnin, Estelle; Quéméner, Bernard; Hellìn, Pilar; Thibault, Jean-François

2005-08-01

Homogalacturonan-derived partly methylated and/or acetylated oligogalacturonates were recovered after enzymatic hydrolysis (endo-polygalacturonase+pectin methyl esterase+side-chain degrading enzymes) of sugar beet pectin followed by anion-exchange and size exclusion chromatography. Around 90% of the GalA and 75% of the acetyl groups present in the initial sugar beet pectin were recovered as homogalacturonan-derived oligogalacturonates, the remaining GalA and acetyl belonging to rhamnogalacturonic regions. Around 50% of the acetyl groups present in sugar beet homogalacturonans were recovered as partly methylated and/or acetylated oligogalacturonates of degree of polymerisation 5 whose structures were determined by electrospray ionization ion trap mass spectrometry (ESI-IT-MSn). 2-O-acetyl- and 3-O-acetyl-GalA were detected in roughly similar amounts but 2,3-di-O-acetylation was absent. Methyl-esterified GalA residues occurred mainly upstream 2-O-acetyl GalA. Oligogalacturonates containing GalA residues that are at once methyl- and acetyl-esterified were recovered in very limited amounts. A tentative mapping of the distribution of acetyl and methyl esters within sugar beet homogalacturonans is proposed. Unsubstituted GalA residues are likely to be present in limited amounts (approximately 10% of total GalA residues), due to the fact that methyl and acetyl groups are assumed to be most often not carried by the same residues.

On-line characterization using ultrasound of pectin hydrolysis catalyzed by the enzyme pectinmethylesterase

Science.gov (United States)

Aparicio, C.; Resa, P.; Sierra, C.; Elvira, L.

2012-12-01

The major problem in the fruit juice industry is associated with juice quality deterioration due to the cloud loss of juice concentrates by the enzymatic reaction of pectinmethylesterase enzyme (PME, EC 3.1.1.11). During pectin hydrolysis, pectin and water are transformed into polygalacturonic acid (pectate) and methanol by the action of PME. In this work, a low-intensity ultrasonic technique is used to monitor this enzymatic reaction, with PME both from orange peel and from Aspergillus niger. Changes in sound velocity during pectin hydrolysis (1% concentration of pectin, T = 30°C and pH = 4.5 and 7) with 0.25 ml of enzyme solution (PME) have been measured using a through-transmission technique. Sound velocity decreases as pectin is transformed into pectate and methanol and at the end of the process, the change in sound velocity reaches 0.3 m/s with PME from orange peel and 0.33 m/s with PME from Aspergillus niger.

On-line characterization using ultrasound of pectin hydrolysis catalyzed by the enzyme pectinmethylesterase

International Nuclear Information System (INIS)

Aparicio, C; Resa, P; Sierra, C; Elvira, L

2012-01-01

The major problem in the fruit juice industry is associated with juice quality deterioration due to the cloud loss of juice concentrates by the enzymatic reaction of pectinmethylesterase enzyme (PME, EC 3.1.1.11). During pectin hydrolysis, pectin and water are transformed into polygalacturonic acid (pectate) and methanol by the action of PME. In this work, a low-intensity ultrasonic technique is used to monitor this enzymatic reaction, with PME both from orange peel and from Aspergillus niger. Changes in sound velocity during pectin hydrolysis (1% concentration of pectin, T = 30°C and pH = 4.5 and 7) with 0.25 ml of enzyme solution (PME) have been measured using a through-transmission technique. Sound velocity decreases as pectin is transformed into pectate and methanol and at the end of the process, the change in sound velocity reaches 0.3 m/s with PME from orange peel and 0.33 m/s with PME from Aspergillus niger.

Characterization of hop pectins shows the presence of an arabinogalactan-protein

NARCIS (Netherlands)

Oosterveld, A.; Voragen, A.G.J.; Schols, H.A.

2002-01-01

Hop pectins were extracted from spent hops using acid extraction conditions and were characterized chemically. The acid extraction of spent hops resulted in a yield of 2°containing 59 f polysaccharides. The hop pectins under investigation had a relatively high molecular weight and an intrinsic

Effect of dry-heating with pectin on gelatinization properties of sweet ...

African Journals Online (AJOL)

Purpose: To evaluate the effect of dry-heating with pectin at different dry heating temperatures, heating times and pH on the gelatinization properties of sweet potato starch. Methods: The gelatinization properties of sweet potato starch - pectin blend were analyzed using a rapid viscosity analyzer (RVA), differential scanning ...

Effect of temperature and high pressure on the activity and mode of action of fungal pectin methyl esterase.

Science.gov (United States)

Duvetter, Thomas; Fraeye, Ilse; Sila, Daniel N; Verlent, Isabel; Smout, Chantal; Clynen, Elke; Schoofs, Liliane; Schols, Henk; Hendrickx, Marc; Van Loey, Ann

2006-01-01

Pectin was de-esterified with purified recombinant Aspergillus aculeatus pectin methyl esterase (PME) during isothermal-isobaric treatments. By measuring the release of methanol as a function of treatment time, the rate of enzymatic pectin conversion was determined. Elevated temperature and pressure were found to stimulate PME activity. The highest rate of PME-catalyzed pectin de-esterification was obtained when combining pressures in the range 200-300 MPa with temperatures in the range 50-55 degrees C. The mode of pectin de-esterification was investigated by characterizing the pectin reaction products by enzymatic fingerprinting. No significant effect of increasing pressure (300 MPa) and/or temperature (50 degrees C) on the mode of pectin conversion was detected.

21 CFR 184.1588 - Pectins.

Science.gov (United States)

2010-04-01

... CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific.... Pectin is produced commercially by extracting citrus peel, apple pomace, or beet pulp with hot dilute... affirmation of these ingredients as generally recognized as safe (GRAS) as direct human food ingredients is...

Utilization of Aspergillus oryzae to produce pectin lyase from various agro-industrial residues

OpenAIRE

Koser, Safia; Anwar, Zahid; Iqbal, Zafar; Anjum, Awais; Aqil, Tahir; Mehmood, Sajid; Irshad, Muhammad

2014-01-01

The present study was aimed to investigate the culture influence on pectin lyase production potential of fungal strain Aspergillus oryzae. The enzyme profile of A. oryzae showed highest activity of pectin lyase after 3rd day of incubation on lemon peel waste under solid state fermentation conditions. To induce the pectin lyase synthesis capability of A. oryzae at optimal level various culture variables including physical and nutritional parameters were optimized by adopting classical optimiza...

Application of enzymes for efficient extraction, modification, and development of functional properties of lime pectin

DEFF Research Database (Denmark)

Dominiak, Malgorzata Maria; Marie Søndergaard, Karen; Wichmann, Jesper

2014-01-01

pectin. The most efficient enzyme preparation was Laminex C2K derived from Penicillium funiculosum which, during 4 h treatment at pH 3.5, 50 °C, released pectin with similar yield (23% w/w), molecular weight (69 kDa), and functional properties e.g. gelling, stabilization of acidified milk drinks...... and viscosity as the classically acid-extracted pectins (8 h treatment at 70 °C, pH ... at higher temperatures. The Laminex CK2 extracted pectin polymers were not sensitive to the presence of Ca2+ ions, they formed a gel at low pH in the presence of sugar and were able to stabilize acidified milk drinks. Further modification by enzymatic de-esterification of the pectin extracted with Laminex C...

Dietary fibre components and pectin chemical features of peels during ripening in banana and plantain varieties.

Science.gov (United States)

Happi Emaga, Thomas; Robert, Christelle; Ronkart, Sébastien N; Wathelet, Bernard; Paquot, Michel

2008-07-01

The effects of the ripeness stage of banana (Musa AAA) and plantain (Musa AAB) peels on neutral detergent fibre, acid detergent fibre, cellulose, hemicelluloses, lignin, pectin contents, and pectin chemical features were studied. Plantain peels contained a higher amount of lignin but had a lower hemicellulose content than banana peels. A sequential extraction of pectins showed that acid extraction was the most efficient to isolate banana peel pectins, whereas an ammonium oxalate extraction was more appropriate for plantain peels. In all the stages of maturation, the pectin content in banana peels was higher compared to plantain peels. Moreover, the galacturonic acid and methoxy group contents in banana peels were higher than in plantain peels. The average molecular weights of the extracted pectins were in the range of 132.6-573.8 kDa and were not dependant on peel variety, while the stage of maturation did not affect the dietary fibre yields and the composition in pectic polysaccharides in a consistent manner. This study has showed that banana peels are a potential source of dietary fibres and pectins.

Pectin from Opuntia ficus indica: Optimization of microwave-assisted extraction and preliminary characterization.

Science.gov (United States)

Lefsih, Khalef; Giacomazza, Daniela; Dahmoune, Farid; Mangione, Maria Rosalia; Bulone, Donatella; San Biagio, Pier Luigi; Passantino, Rosa; Costa, Maria Assunta; Guarrasi, Valeria; Madani, Khodir

2017-04-15

Optimization of microwave-assisted extraction (MAE) of water-soluble pectin (WSP) from Opuntia ficus indica cladodes was performed using Response Surface Methodology. The effect of extraction time (X 1 ), microwave power (X 2 ), pH (X 3 ) and solid-to-liquid ratio (X 4 ) on the extraction yield was examined. The optimum conditions of MAE were as follows: X 1 =2.15min; X 2 =517W; X 3 =2.26 and X 4 =2g/30.6mL. The maximum obtained yield of pectin extraction was 12.57%. Total carbohydrate content of WSP is about 95.5% including 34.4% of Galacturonic acid. Pectin-related proteins represent only the 0.66% of WSP mass. HPSEC and light scattering analyses reveal that WSP is mostly constituted of high molecular pectin and FTIR measurements show that the microwave treatment does not alter the chemical structure of WSP, in which Galacturonic acid content and yield are 34.4% and 4.33%, respectively. Overall, application of MAE can give rise to high quality pectin. Copyright © 2016 Elsevier Ltd. All rights reserved.

Aqueous extraction of pectin from sour orange peel and its preliminary physicochemical properties.

Science.gov (United States)

Hosseini, Seyed Saeid; Khodaiyan, Faramarz; Yarmand, Mohammad Saeid

2016-01-01

Sour orange peel, a by-product of the fruit juice industry, was used as a source of pectin. The effects of temperature (75-95°C), time (30-90 min), and liquid-solid ratio (20-40, v/w) were investigated on yield, methoxylation degree (DE), and galacturonic acid content using a Box-Behnken design and response surface methodology. The highest extraction yield (17.95 ± 0.3%) was obtained at temperature of 95°C, time of 90 min, and liquid-solid ratio of 25 (v/w). The DE values for the pectin ranged from 17% to 30.5%, indicating that the pectin was low in methoxyle. The emulsifying activity of pectin extracted under optimal conditions was 45%. The emulsions were 86.6% stable at 4°C and 71.4% at 23°C after 30 days of storage. The pectin exhibited Newtonian flow at low concentrations (≤ 1.0%, w/v); as the concentration increased, pseudoplastic flow became dominant. Copyright © 2015 Elsevier B.V. All rights reserved.

[Cocoa (Theobroma cacao L.) hulls: a posible commercial source of pectins].

Science.gov (United States)

Barazarte, Humberto; Sangronis, Elba; Unai, Emaldi

2008-03-01

Commercial exploitation of cocoa (Theobroma cacao L.) generates a volume of hulls that could be used in the production of pectins on an industrial scale. Therefore, pectins from cocoa hulls were extracted at different pH and temperature conditions, and their main chemical characteristics were evaluated. EDTA at 0.5% was used for the extraction at pHs 3, 4 and 5 and temperatures of 60, 75 and 90 degrees C, under a 3 2 factorial design. The response variables were yield, content of anhydrous galacturonic acid (AGA), content of metoxil, degree of esterification and equivalent weight of the pectins extracted. The strength of the pectic gel was determined with a TA-XT2 texturometer. Strawberry jam was made with the pectin extracted, and its acceptability was determined using a 7-point hedonic scale. The results obtained were as follows: an extraction yield from 2.64 to 4.69 g/100 g; an AGA content between 49.8 and 64.06 g/100 g; a content of metoxil between 4.72 and 7.18 g/100 g; a degree of esterification between 37.94 and 52.20%; an equivalent weight from 385.47 to 464.61 g/equivalent of H+, and a degree of gelation between 28.64 and 806.03 g force. The pectin extracted at pH 4 and 90 degrees C showed a gelation power of 422.16 g force, purity 62.26 g/100 g of AGA, and a yield of extraction of 3.89 g/100 g and allowed to prepare ajam with an average level of liking of "like moderately". Pectins from cocoa hulls show potential application in the food industry, but it is necessary to optimize the extraction parameters to increase its yield.

Characterization of citrus pectin samples extracted under different conditions: influence of acid type and pH of extraction

DEFF Research Database (Denmark)

Kaya, Merve; Sousa, Antonio G.; Crepeau, Marie-Jeanne

2014-01-01

on the chemical and macromolecular characteristics of pectin samples. Methods Citrus peel (orange, lemon, lime and grapefruit) from a commercial supplier was used as raw material. Pectin samples were obtained on a bulk plant scale (kilograms; harsh nitric acid, mild nitric acid and harsh oxalic acid extraction......) and on a laboratory scale (grams; mild oxalic acid extraction). Pectin composition (acidic and neutral sugars) and physicochemical properties (molar mass and intrinsic viscosity) were determined. Key Results Oxalic acid extraction allowed the recovery of pectin samples of high molecular weight. Mild oxalic acid......-extracted pectins were rich in long homogalacturonan stretches and contained rhamnogalacturonan I stretches with conserved side chains. Nitric acid-extracted pectins exhibited lower molecular weights and contained rhamnogalacturonan I stretches encompassing few and/or short side chains. Grapefruit pectin was found...

Pectins filled with LDH-antimicrobial molecules: preparation, characterization and physical properties.

Science.gov (United States)

Gorrasi, Giuliana; Bugatti, Valeria; Vittoria, Vittoria

2012-06-05

Nanohybrids of layered double hydroxide (LDH) with intercalated active molecules: benzoate, 2,4-dichlorobenzoate, para-hydroxybenzoate and ortho-hydroxybenzoate, were incorporated into pectins from apples through high energy ball milling in the presence of water. Cast films were obtained and analysed. X-ray diffraction analysis showed a complete destructuration of all nanohybrids in the pectin matrix. Thermogravimetric analysis showed a better thermal resistance of pectin in the presence of fillers, especially para-hydroxybenzoate and ortho-hydroxybenzoate. Mechanical properties showed an improvement of elastic modulus in particular for LDH-para-hydroxybenzoate nanohybrid, due probably to a better interaction between pectin matrix and nanohybrid layers. Barrier properties (sorption and diffusion) to water vapour showed improvement in the dependence on the intercalated active molecule, the best improvement was achieved for composites containing para-hydroxybenzoate molecules, suggesting that the interaction between the filler phase and the polymer plays an important role in sorption and diffusion phenomena. Incorporation of these active molecules gave antimicrobial properties to the composite films giving opportunities in the field of active packaging. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rheological evaluation of the irradiated pectin/gelatin mixed systems

International Nuclear Information System (INIS)

Inamura, Patricia Y.; Mastro, Nelida L. del

2011-01-01

The main biopolymers used in the edible films production are polysaccharides and proteins. Pectin is a heterosaccharidic polymer derived from the vegetal cell wall. Gelatin is a heterogeneous mixture of water-soluble proteins of high average molecular mass derived by hydrolytic action from animal collagen. The aim of this research was to evaluate the effect of ionizing radiation on either the biopolymers alone or on the mixed systems prepared with high-and low-methoxyl pectin and gelatin in solution and mixed gel. The results showed that gelatin viscosity remained almost unaffected by the irradiation with doses from 1 to 15 kGy, with a slight increase at 3 kGy. On the other hand, there was a sharp decrease of viscosity values of all pectin solutions upon irradiation, being this behavior predominant when both polysaccharides and proteins were present in a mixed system. The gel hardness and gel brittleness of the gelatin were affected by the increase of radiation dose. (author)

Inhibition of Pectin Methyl Esterase Activity By Green Tea Catechins

OpenAIRE

Sagi, Irit; Lewis, Kristin; Tworowski, Dmitry; Shahar, Chen; Selzer, Tzvia

2008-01-01

Pectin methyl esterases (PMEs) and their endogenous inhibitors are involved in the regulation of many processes in plant physiology, ranging from tissue growth and fruit ripening to parasitic plant haustorial formation and host invasion. Thus, control of PME activity is critical for enhancing our understanding of plant physiological processes and regulation. Here we report on the identification of epigallocatechin gallate (EGCG), a green tea component, as a natural inhibitor for pectin ...

Potential utilization of Citrullus lanatus var. Colocynthoides waste as a novel source of pectin.

Science.gov (United States)

Korish, Mohamed

2015-04-01

The Citrullus lanatus var. Colocynthoides is an ancestor type of watermelon. It was investigated as a new source of pectin. It was cultivated in Egypt for seeds only, while the remaining fruits are discarded as waste. Effect of different extraction conditions such as pH, solid: liquid ratio, temperature and extraction time on pectin yield of Citrullus lanatus var. Colocynthoides waste was investigated in the present study. The highest yield (19.75 % w/w) was achieved at pH 2, solid: liquid ratio1:15 and 85 °C, for 60 min. Methylation degree and galacturonic acid content of extracted pectin were 55.25 %, w/w and 76.84 %, w/w. The main neutral sugars were galactose followed by arabinose and rhamnose. In addition, glucose, xylose and mannose existed as constituents in the pectin hydrolysate. The results indicated that Citrullus lanatus var. Colocynthoide waste is a potential new source of pectin.

Process optimization and analysis of microwave assisted extraction of pectin from dragon fruit peel.

Science.gov (United States)

Thirugnanasambandham, K; Sivakumar, V; Prakash Maran, J

2014-11-04

Microwave assisted extraction (MAE) technique was employed for the extraction of pectin from dragon fruit peel. The extracting parameters were optimized by using four-variable-three-level Box-Behnken design (BBD) coupled with response surface methodology (RSM). RSM analysis indicated good correspondence between experimental and predicted values. 3D response surface plots were used to study the interactive effects of process variables on extraction of pectin. The optimum extraction conditions for the maximum yield of pectin were power of 400 W, temperature of 45 °C, extracting time of 20 min and solid-liquid ratio of 24 g/mL. Under these conditions, 7.5% of pectin was extracted. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synthesis and characterization of thiolated pectin stabilized gold coated magnetic nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Arora, Varun, E-mail: varun.arora3986@gmail.com [University School of Basic and Applied Sciences, Guru Gobind Singh Indraprastha University, Sector 16-C, Dwarka, New Delhi 110078 (India); Sood, Ankur, E-mail: ankursood02@gmail.com [University School of Basic and Applied Sciences, Guru Gobind Singh Indraprastha University, Sector 16-C, Dwarka, New Delhi 110078 (India); Shah, Jyoti, E-mail: shah.jyoti1@gmail.com [National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi 110012 (India); Kotnala, R.K., E-mail: rkkotnala@nplindia.org [National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi 110012 (India); Jain, Tapan K., E-mail: tapankjain@gmail.com [University School of Basic and Applied Sciences, Guru Gobind Singh Indraprastha University, Sector 16-C, Dwarka, New Delhi 110078 (India)

2016-04-15

Core–shell nanoparticles, magnetic core and gold shell, were synthesized by reduction of gold chloride on the surface of magnetic nanoparticles; using tyrosine as a reducing agent. The formation of gold shell on magnetic nanoparticles was confirmed by X-ray diffraction (XRD) and UV-Visible spectroscopy. The core–shell nanoparticles (CSn) were conjugated with thiolated pectin to form a stable aqueous dispersion. The hydrodynamic size of thiolated pectin stabilized core–shell nanoparticles (TP-CSn) measured by Dynamic light scattering (DLS) was 160.5 nm with a poly dispersity index (PDI) of 0.302, whereas the mean particle size of TP-CSn calculated by high resolution transmission electron microscopy (HRTEM) was 10.8 ± 2.7 nm. The value of zeta potential for TP-CSn was −13.6 mV. There was a decrease in the value of saturation magnetization upon formation of the gold shell on magnetic nanoparticles. The amount of thiolated pectin bound to the surface of core–shell nanoparticles, calculated using Thermogravimetric analysis (TGA), was 6% of sample weight. - Highlights: • Use of side group of tyrosine (phenol) as a pH dependent reducing agent to synthesize gold coated magnetic nanoparticles. • Successful coating of gold shell on magnetic nanoparticles core. • Synthesis of thiolated pectin and stabilization of aqueous dispersion of core–shell nanoparticles with thiolated pectin. • The superparamagnetic behaviour of magnetic nanoparticles is retained after shell formation.

Characterization of citrus pectin samples extracted under different conditions: influence of acid type and pH of extraction

Science.gov (United States)

Kaya, Merve; Sousa, António G.; Crépeau, Marie-Jeanne; Sørensen, Susanne O.; Ralet, Marie-Christine

2014-01-01

Background and Aims Pectin is a complex macromolecule, the fine structure of which is influenced by many factors. It is used as a gelling, thickening and emulsifying agent in a wide range of applications, from food to pharmaceutical products. Current industrial pectin extraction processes are based on fruit peel, a waste product from the juicing industry, in which thousands of tons of citrus are processed worldwide every year. This study examines how pectin components vary in relation to the plant source (orange, lemon, lime, grapefruit) and considers the influence of extraction conditions on the chemical and macromolecular characteristics of pectin samples. Methods Citrus peel (orange, lemon, lime and grapefruit) from a commercial supplier was used as raw material. Pectin samples were obtained on a bulk plant scale (kilograms; harsh nitric acid, mild nitric acid and harsh oxalic acid extraction) and on a laboratory scale (grams; mild oxalic acid extraction). Pectin composition (acidic and neutral sugars) and physicochemical properties (molar mass and intrinsic viscosity) were determined. Key Results Oxalic acid extraction allowed the recovery of pectin samples of high molecular weight. Mild oxalic acid-extracted pectins were rich in long homogalacturonan stretches and contained rhamnogalacturonan I stretches with conserved side chains. Nitric acid-extracted pectins exhibited lower molecular weights and contained rhamnogalacturonan I stretches encompassing few and/or short side chains. Grapefruit pectin was found to have short side chains compared with orange, lime and lemon. Orange and grapefruit pectin samples were both particularly rich in rhamnogalacturonan I backbones. Conclusions Structural, and hence macromolecular, variations within the different citrus pectin samples were mainly related to their rhamnogalacturonan I contents and integrity, and, to a lesser extent, to the length of their homogalacturonan domains. PMID:25081519

Effects of Apple Juice Concentrate, Blackcurrant Concentrate and Pectin Levels on Selected Qualities of Apple-Blackcurrant Fruit Leather

Directory of Open Access Journals (Sweden)

Lemuel M. Diamante

2013-09-01

Full Text Available A study was conducted to determine the effects of different levels of apple juice concentrate (AJC, blackcurrant concentrate (BCC and pectin on the moisture content, water activity, color, texture and ascorbic acid content of apple-blackcurrant fruit leather using the response surface methodology. The results showed the moisture content increased with increasing pectin level and with greater increases at higher AJC and BCC levels while the water activity increased with increasing pectin level and with increasing AJC level, at low pectin levels, but with decreasing AJC, at high pectin levels. The chroma decreased with increasing pectin level and with lower values at the middle AJC level. The puncturing force decreased with increasing AJC level but with a lower value at the middle pectin level. Lastly, the ascorbic acid content increased with increasing BCC level regardless of AJC and pectin levels. There is a need to reduce the drying temperature or time of apple-blackcurrant fruit leather just enough to bring the water activity closer to 0.60, thereby increasing the moisture content resulting in higher product yield.

Effects of Apple Juice Concentrate, Blackcurrant Concentrate and Pectin Levels on Selected Qualities of Apple-Blackcurrant Fruit Leather.

Science.gov (United States)

Diamante, Lemuel M; Li, Siwei; Xu, Qianqian; Busch, Janette

2013-09-12

A study was conducted to determine the effects of different levels of apple juice concentrate (AJC), blackcurrant concentrate (BCC) and pectin on the moisture content, water activity, color, texture and ascorbic acid content of apple-blackcurrant fruit leather using the response surface methodology. The results showed the moisture content increased with increasing pectin level and with greater increases at higher AJC and BCC levels while the water activity increased with increasing pectin level and with increasing AJC level, at low pectin levels, but with decreasing AJC, at high pectin levels. The chroma decreased with increasing pectin level and with lower values at the middle AJC level. The puncturing force decreased with increasing AJC level but with a lower value at the middle pectin level. Lastly, the ascorbic acid content increased with increasing BCC level regardless of AJC and pectin levels. There is a need to reduce the drying temperature or time of apple-blackcurrant fruit leather just enough to bring the water activity closer to 0.60, thereby increasing the moisture content resulting in higher product yield.

SURFACE-ACTIVE PROPERTIES OF THE DISTILLERS GRAINS AND THE PECTINS ISOLATED FROM THEM

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N. S. Kaisheva

2016-01-01

Full Text Available Distillers grains are a huge secondary raw material resource, prospective for different fields, including pharmaceutical use, because of a rich content of biologically active compounds. The purpose of this paper was to estimate possibilities of the pharmaceutical use of distillers grains as the additive agent by means of surface-active properties of distillers grains study as well as pectins, isolated from them. We have established the surface-active properties of the liquid phase of the distillers wheat grains by means of higher pressure of air bubbles with the use of Rehbinder’s apparatus. It contained 6.67 mol/m3 pectins, and pectins isolated from a solid phase of the same distillers grains: surface activity 11.67 and 7.54, saturated surface excess amounted to 1.28×10-5 and 6.25×10-5 mol/m2, critical concentration of micelle formation amounted to 1.32 mol/m3 and 1.48 mol/m3 respectively. Surface-active characteristics of distillers grains and isolated pectins are comparable with well-known natural polysaccharides (sodium alginate, polygalacturonic acid, beet bin pectin, which are used as additive agents in technology of medicinal plants. We have determined the sizes of pectins molecules from distillers grains in the unsaturated adsorption layers, which differed from the well-known polysaccharides by lesser square (2.658 Å2, radius (0.920 Å, diameter of cross-section (1.840 Å and the volume (2727 Å3 at the bigger mass per surface unit (1.031×10-4 кг and a length (1026 Å. The data obtained by the sizes of pectin molecules are the favorable factor, which conduced their high biological availability. 

Independent Assessment of the Savannah River Site High-Level Waste Salt Disposition Alternatives Evaluation

International Nuclear Information System (INIS)

Case, J. T.; Renfro, M. L.

1998-01-01

This report presents the results of the Independent Project Evaluation (IPE) Team assessment of the Westinghouse Savannah River Company High-Level Waste Salt Disposition Systems Engineering (SE) Team's deliberations, evaluations, and selections. The Westinghouse Savannah River Company concluded in early 1998 that production goals and safety requirements for processing SRS HLW salt to remove Cs-137 could not be met in the existing In-Tank Precipitation Facility as currently configured for precipitation of cesium tetraphenylborate. The SE Team was chartered to evaluate and recommend an alternative(s) for processing the existing HLW salt to remove Cs-137. To replace the In-Tank Precipitation process, the Savannah River Site HLW Salt Disposition SE Team down-selected (October 1998) 140 candidate separation technologies to two alternatives: Small-Tank Tetraphenylborate (TPB) Precipitation (primary alternative) and Crystalline Silicotitanate (CST) Nonelutable Ion Exchange (backup alternative). The IPE Team, commissioned by the Department of Energy, concurs that both alternatives are technically feasible and should meet all salt disposition requirements. But the IPE Team judges that the SE Team's qualitative criteria and judgments used in their down-selection to a primary and a backup alternative do not clearly discriminate between the two alternatives. To properly choose between Small-Tank TPB and CST Ion Exchange for the primary alternative, the IPE Team suggests the following path forward: Complete all essential R and D activities for both alternatives and formulate an appropriate set of quantitative decision criteria that will be rigorously applied at the end of the R and D activities. Concurrent conceptual design activities should be limited to common elements of the alternatives

Zein/caseinate/pectin complex nanoparticles: Formation and characterization.

Science.gov (United States)

Chang, Chao; Wang, Taoran; Hu, Qiaobin; Luo, Yangchao

2017-11-01

In this study, pectin was used as coating material to form zein/caseinate/pectin complex nanoparticles through pH adjustment and heating treatment for potential oral delivery applications. The preparation conditions were studied by applying heating treatment at different pHs, either the isoelectric point of zein (pH 6.2) or caseinate (pH 4.6), or consecutively at both pHs. The particulate characteristics, including particle size, polydispersity index, and zeta potential were monitored for complex nanoparticles formed under different preparation conditions. The complex nanoparticles generally exhibited particle size smaller than 200nm with narrow distribution, spherical shape, and strong negative charge. Fourier transform infrared and fluorescence spectroscopy revealed that hydrophobic interactions and hydrogen bonds were involved in the formation of complex nanoparticles, in addition to electrostatic interactions. Fresh colloidal dispersion and freeze-dried powders varied in their morphology, depending on their preparation conditions. Our results suggested that heating pH and sequence significantly affected the morphology of complex nanoparticles, and pectin coating exerted stabilization effect under simulated gastrointestinal conditions. The present study provides insight into the formation of protein/polysaccharide complex nanoparticles under different preparation conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Propidium iodide competes with Ca(2+) to label pectin in pollen tubes and Arabidopsis root hairs.

Science.gov (United States)

Rounds, Caleb M; Lubeck, Eric; Hepler, Peter K; Winship, Lawrence J

2011-09-01

We have used propidium iodide (PI) to investigate the dynamic properties of the primary cell wall at the apex of Arabidopsis (Arabidopsis thaliana) root hairs and pollen tubes and in lily (Lilium formosanum) pollen tubes. Our results show that in root hairs, as in pollen tubes, oscillatory peaks in PI fluorescence precede growth rate oscillations. Pectin forms the primary component of the cell wall at the tip of both root hairs and pollen tubes. Given the electronic structure of PI, we investigated whether PI binds to pectins in a manner analogous to Ca(2+) binding. We first show that Ca(2+) is able to abrogate PI growth inhibition in a dose-dependent manner. PI fluorescence itself also relies directly on the amount of Ca(2+) in the growth solution. Exogenous pectin methyl esterase treatment of pollen tubes, which demethoxylates pectins, freeing more Ca(2+)-binding sites, leads to a dramatic increase in PI fluorescence. Treatment with pectinase leads to a corresponding decrease in fluorescence. These results are consistent with the hypothesis that PI binds to demethoxylated pectins. Unlike other pectin stains, PI at low yet useful concentration is vital and specifically does not alter the tip-focused Ca(2+) gradient or growth oscillations. These data suggest that pectin secretion at the apex of tip-growing plant cells plays a critical role in regulating growth, and PI represents an excellent tool for examining the role of pectin and of Ca(2+) in tip growth.

Extraction of pectin from passion fruit rind (Passiflora edulis var. flavicarpa Degener) for edible coating

Science.gov (United States)

Inayati, Puspita, Rifka Intan; Fajrin, Vika Latifiana

2018-02-01

One of fruit preservation method is by applying the edible coating. Rind of passion fruit (Passiflora edulis var. flavicarpa Degener), which is kind of waste, can be utilized as edible coating through pectin extraction process. The purposes of this work were to determine the suitable solvent for the pectin extraction and techniques for applying the produced edible coating on strawberry, to produce edible coating from the pectin, and the test the performance of the edible coating which was applied to strawberries. Pectin from passion fruit rind was collected through conventional extraction method using two types of solvent, i.e. acetic acid solution and hydrochloric acid solution with concentration of 0.01 N, 0.015 N, 0.02 N, 0.025 N, and 0.03 N. The results showed that chloric acid solution was more suitable for the pectin extraction from passion fruit. Maximum yield of 30.78% was obtained at hydrochloric acid concentration of 0.02 N. Obtained pectin from the extraction was then processed into the edible coating by adding plasticizers and calcium chloride dihydrate. Storability of the coated strawberry was observed to measure the performance of the edible coating

Combined HILIC-ELSD/ESI-MSn enables the separation, identification and quantification of sugar beet pectin derived oligomers

NARCIS (Netherlands)

Remoroza, C.A.; Cord-Landwehr, S.; Leijdekkers, A.G.M.; Moerschbacher, B.M.; Schols, H.A.; Gruppen, H.

2012-01-01

The combined action of endo-polygalacturonase (endo-PGII), pectin lyase (PL), pectin methyl esterase (fungal PME) and RG-I degrading enzymes enabled the extended degradation of methylesterified and acetylated sugar beet pectins (SBPs). The released oligomers were separated, identified and quantified

A Bacillus licheniformis pectin acetylesterase is specific for homogalacturonans acetylated at O-3

NARCIS (Netherlands)

Remoroza, C.A.; Wagenknecht, M.; Buchholt, H.C.; Moerschbacher, B.M.; Schols, H.A.; Gruppen, H.

2014-01-01

A recombinant acetylesterase from Bacillus licheniformis DSM13, belonging to carbohydrate esterase family 12, was purified and biochemically characterized. The purified enzyme, termed BliPAE, was capable of deacetylating acetylated pectins, e.g. sugar beet pectin (SBP). Contrary to its provisional

Physicochemical and Antimicrobial Properties of Cocoa Pod Husk Pectin Intended as a Versatile Pharmaceutical Excipient and Nutraceutical

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Ofosua Adi-Dako

2016-01-01

Full Text Available The physicochemical and antimicrobial properties of cocoa pod husk (CPH pectin intended as a versatile pharmaceutical excipient and nutraceutical were studied. Properties investigated include pH, moisture content, ash values, swelling index, viscosity, degree of esterification (DE, flow properties, SEM, FTIR, NMR, and elemental content. Antimicrobial screening and determination of MICs against test microorganisms were undertaken using agar diffusion and broth dilution methods, respectively. CPH pectin had a DE of 26.8% and exhibited good physicochemical properties. Pectin had good microbiological quality and exhibited pseudoplastic, shear thinning behaviour, and high swelling capacity in aqueous media. The DE, FTIR, and NMR results were similar to those of previous studies and supported highly acetylated low methoxy pectin. CPH pectin was found to be a rich source of minerals and has potential as a nutraceutical. Pectin showed dose-dependent moderate activity against gram positive and gram negative microorganisms but weak activity against Listeria spp. and A. niger. The MICs of pectin ranged from 0.5 to 4.0 mg/mL, with the highest activity against E. coli and S. aureus (MIC: 0.5–1.0 mg/mL and the lowest activity against A. niger (MIC: 2.0–4.0 mg/mL. The study has demonstrated that CPH pectin possesses the requisite properties for use as a nutraceutical and functional pharmaceutical excipient.

Structural diversity of pectins isolated from the Styrian oil-pumpkin (Cucurbita pepo var. styriaca) fruit.

Science.gov (United States)

Košťálová, Zuzana; Hromádková, Zdenka; Ebringerová, Anna

2013-03-01

To evaluate the seeded fruit biomass of the Styrian oil-pumpkin in view of its pectin component, a series of acidic polysaccharides were isolated by a six-step sequential extraction using hot water, EDTA, dilute HCl (twice) and dilute and stronger NaOH solutions. Chemical, physicochemical and spectroscopy analyses revealed that the first four fractions comprised partially methyl-esterified and acetylated pectins with varying proportions of rhamnogalacturonan regions ramified with galactose- and arabinose-containing side chains and showed considerable polymolecularity. The alkali-extracted polysaccharides contained lower amounts of pectins with homogalacturonan and arabinose-rich rhamnogalacturonan regions next to hemicelluloses prevailing in the last polysaccharide. Using (1)H-(13)C HSQC and HMBC spectroscopy, the resonances of free and methylesterified galacturonic acid residues in the purified acid-extracted pectin were unambiguously established and various diads formed by both residues identified. The results might serve as a basis for searching technological conditions to produce pectin from the oil-pumpkin fruit biomass. Copyright © 2012 Elsevier Ltd. All rights reserved.

Requirement for Pectin Methyl Esterase and Preference for Fragmented over Native Pectins for Wall-associated Kinase-activated, EDS1/PAD4-dependent Stress Response in Arabidopsis*

Science.gov (United States)

Kohorn, Bruce D.; Kohorn, Susan L.; Saba, Nicholas J.; Martinez, Victoriano Meco

2014-01-01

The wall-associated kinases (WAKs) have a cytoplasmic protein kinase domain that spans the plasma membrane and binds pectin in the extracellular matrix of plants. WAKs are required for cell expansion during Arabidopsis seedling development but are also an integral part of the response to pathogens and stress that present oligogalacturonides (OGs), which subsequently bind to WAKs and activate a MPK6 (mitogen-activated protein kinase)-dependent pathway. It was unclear how WAKs distinguish native pectin polymers and OGs to activate one or the other of these two pathways. A dominant allele of WAK2 constitutively activates the stress response, and we show here that the effect is dependent upon EDS1 and PAD4, transcriptional activators involved in the pathogen response. Moreover, the WAK2 dominant allele is suppressed by a null allele of a pectin methyl esterase (PME3) whose activity normally leads to cross-linking of pectins in the cell wall. Although OGs activate a transcriptional response in wild type, the response is enhanced in a pme3/pme3 null, consistent with a competition by OG and native polymers for activation of WAKs. This provides a plausible mechanism for WAKs to distinguish an expansion from a stress pathway. PMID:24855660

Requirement for pectin methyl esterase and preference for fragmented over native pectins for wall-associated kinase-activated, EDS1/PAD4-dependent stress response in Arabidopsis.

Science.gov (United States)

Kohorn, Bruce D; Kohorn, Susan L; Saba, Nicholas J; Martinez, Victoriano Meco

2014-07-04

The wall-associated kinases (WAKs) have a cytoplasmic protein kinase domain that spans the plasma membrane and binds pectin in the extracellular matrix of plants. WAKs are required for cell expansion during Arabidopsis seedling development but are also an integral part of the response to pathogens and stress that present oligogalacturonides (OGs), which subsequently bind to WAKs and activate a MPK6 (mitogen-activated protein kinase)-dependent pathway. It was unclear how WAKs distinguish native pectin polymers and OGs to activate one or the other of these two pathways. A dominant allele of WAK2 constitutively activates the stress response, and we show here that the effect is dependent upon EDS1 and PAD4, transcriptional activators involved in the pathogen response. Moreover, the WAK2 dominant allele is suppressed by a null allele of a pectin methyl esterase (PME3) whose activity normally leads to cross-linking of pectins in the cell wall. Although OGs activate a transcriptional response in wild type, the response is enhanced in a pme3/pme3 null, consistent with a competition by OG and native polymers for activation of WAKs. This provides a plausible mechanism for WAKs to distinguish an expansion from a stress pathway. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Preparation and Pb(II Adsorption Properties of Crosslinked Pectin-Carboxymethyl Chitosan Film

Directory of Open Access Journals (Sweden)

Budi Hastuti

2015-11-01

Full Text Available A modified pectin has been synthesized by reacting/combining -OH group among pectin and chitosan with BADGE (Bisphenol A diglycidyl ether crosslinker agent. The structure and morphology of the new material were characterized by Fourier transform infrared (FTIR spectroscopy, scanning electron microscopy (SEM and X-ray Diffraction (XRD analysis. Thermogravimetric studies showed an improvement in thermal characteristic. Adsorption experiments were performed in batch processes; sorption isotherms and kinetics were also studied. The Langmuir and Freundlich adsorption isotherm models were applied to describe the isotherms and isotherm constants for the adsorption of Pb(II ion onto adsorbent pectin-carboxymethyl chitosan-BADGE (pec-CMC-BADGE. The dynamic study showed that the sorption process followed the second-order kinetic equation. Result indicated also that Pb(II ion uptake could be well described by the Langmuir and Freundlich adsorption model of pec-CMC-BADGE and CMC with DG° of 25.3 and 23.1 kJ mol-1,respectively, while that of pectin followed Freundlich isotherm with DG° of 16.6 kJ mol-1.

Reactive hydroxyapatite fillers for pectin biocomposites.

Science.gov (United States)

Munarin, Fabiola; Petrini, Paola; Barcellona, Giulia; Roversi, Tommaso; Piazza, Laura; Visai, Livia; Tanzi, Maria Cristina

2014-12-01

In this work, a novel injectable biocomposite hydrogel is produced by internal gelation, using pectin as organic matrix and hydroxyapatite either as crosslinking agent and inorganic reinforcement. Tunable gelling kinetics and rheological properties are obtained varying the hydrogels' composition, with the final aim of developing systems for cell immobilization. The reversibility by dissolution of pectin-hydroxyapatite hydrogels is achieved with saline solutions, to possibly accelerate the release of the cells or active agents immobilized. Texture analysis confirms the possibility of extruding the biocomposites from needles with diameters from 20 G to 30 G, indicating that they can be implanted with minimally-invasive approaches, minimizing the pain during injection and the side effects of the open surgery. L929 fibroblasts entrapped in the hydrogels survive to the immobilization procedure and exhibit high cell viability. On the overall, these systems result to be suitable supports for the immobilization of cells for tissue regeneration applications. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of gamma irradiation in the viscosity of gelatin and pectin solutions used in food industry

International Nuclear Information System (INIS)

Inamura, Patricia Yoko

2008-01-01

Pectin is a polysaccharide substance of plant origin that may be used as gelling agent, stabilizer in jams, in yogurt drinks and lactic acid beverages. Gelatin, a protein from bovine origin, in this case, is mainly used as gelling agent due to hydrogel formation during cooling. The 60 Co-irradiation process may cause various modifications in macromolecules, some with industrial application, as reticulation. The dynamic response of viscoelastic materials can be used in order to give information about the structural aspect of a system at molecular level. In the present work samples of pectin with different degree of methoxylation, gelatin and the mixture of both were employed to study the radiation sensitivity by means of viscosity measurements. Solutions prepared with citric pectin with high methoxylation content (ATM) 1 por cent, pectin with low content (BTM) 1 por cent, gelatin 0.5 por cent, 1 por cent and 2 por cent, and the mixture 1 por cent and 2 por cent were irradiated with gamma rays at different doses, up to 15 kGy with dose rate about 2 kGy/h. After irradiation the viscosity was measured within a period of 48 h. The viscosity of ATM and BTM pectin solutions decreased sharply with the radiation dose. However, the gelatin sample presented a great radiation resistance. When pectin and gelatin solutions were mixed a predominance of pectin behavior was found. (author)

Yield, Esterification Degree and Molecular Weight Evaluation of Pectins Isolated from Orange and Grapefruit Peels under Different Conditions

Science.gov (United States)

Sayah, Mohamed Yassine; Chabir, Rachida; Benyahia, Hamid; Rodi Kandri, Youssef; Ouazzani Chahdi, Fouad; Touzani, Hanan; Errachidi, Faouzi

2016-01-01

Orange (Citrus sinensis) and grapefruit (Citrus paradise) peels were used as a source of pectin, which was extracted under different conditions. The peels are used under two states: fresh and residual (after essential oil extraction). Organic acid (citric acid) and mineral acid (sulfuric acid) were used in the pectin extraction. The aim of this study is the evaluation the effect of extraction conditions on pectin yield, degree of esterification “DE” and on molecular weight “Mw”. Results showed that the pectin yield was higher using the residual peels. Moreover, both peels allow the obtainment of a high methoxyl pectin with DE >50%. The molecular weight was calculated using Mark-Houwink-Sakurada equation which describes its relationship with intrinsic viscosity. This later was determined using four equations; Huggins equation, kramer, Schulz-Blaschke and Martin equation. The molecular weight varied from 1.538 x1005 to 2.47x1005 g/mol for grapefruit pectin and from 1.639 x1005 to 2.471 x1005 g/mol for orange pectin. PMID:27644093

Chemically Methylated and Reduced Pectins: Preparation and Characterisation by 1H-NMR Spectroscopy, Enzymatic Degradation and Gelling Properties

DEFF Research Database (Denmark)

Rosenbohm, Christoph; Lundt, Inge; Christensen, T.M.I.E.

2003-01-01

with lower DM. A simple method for determination of DM by 1H-NMR spectroscopy is presented. New modified pectins have been prepared by treatment of pectins having different DM’s with NaBH4 to reduce selectively the methyl esters to primary alcohols in the presence of free acids. The degree of reduction (DR......) and the DM of the remaining carboxylic acids could likewise be determined by 1H-NMR spectroscopy. The new reduced pectins can be tolerated by the pectin degrading enzymes polygalacturonase PGI and PGII as well as by pectin lyase, all from Aspergillus niger, but the enzymes exhibit lower specific activities...

Effect of Temperature and High Pressure on the Activity and Mode of Action of Fungal Pectin Methyl Esterase

NARCIS (Netherlands)

Duvetter, T.; Fraeye, I.; Sila, D.N.; Verlent, I.; Smout, C.; Clynen, E.; Schoofs, L.; Schols, H.A.; Hendrickx, M.; Loey, van A.

2006-01-01

Pectin was de-esterified with purified recombinant Aspergillus aculeatus pectin methyl esterase (PME) during isothermal-isobaric treatments. By measuring the release of methanol as a function of treatment time, the rate of enzymatic pectin conversion was determined. Elevated temperature and pressure

Extraction of pectin from apple pomace

Directory of Open Access Journals (Sweden)

Maria Helene Canteri-Schemin

2005-03-01

Full Text Available As apple-processing units are now in expansion in Brazil, industrial by-products like pomace play an important role in pectin manufacture. The objective of this article was to determine a pratical follow-up to the extraction of pectin from apple pomace and to characterize it in a laboratory, on a small scale, aiming at establishing the optimum conditions for acid extraction. The highest yields were obtained when [1]apple pomace was dried and ground to obtain an apple flour to be used as raw material, [2] citric or nitric acids were used and [3] when the citric acid concentration was 6.2 g/100 ml and the time of reaction was 153 minutes. The apple variety in itself was not significant in pectin yield. The degree of esterification (DE = 68.84 % of the product obtained, as well as its physical looks, show the success of pectin extraction.No aproveitamento de resíduos das indústrias processadoras de maçã, em expansão no Brasil, a pectina alimentícia surge como importante subproduto. Os objetivos deste trabalho foram os seguintes: extração e caracterização da pectina de bagaço de maçã em bancada, em que as condições para maior rendimento de obtenção em relação ao tipo de ácido, ao tamanho das partículas e à variedade de maçã foram estabelecidas. Objetivou-se também a otimização da produção, levando-se em conta o tempo e a concentração do ácido cítrico. Foram considerados métodos de extração mais eficientes quanto ao rendimento: [1] acidificação com ácido cítrico ou ácido nítrico, [2] cominuição do bagaço, usando a farinha como matéria-prima, com partículas retidas no tamis de 106 µm, [3] concentração de ácido de 6,2 g% e tempo de extração de 153 minutos. A variedade da maçã não interferiu significativamente no rendimento. A alta metoxilação (DE= 68,84% das pectinas produzidas em bancada confirma o grau de maturidade das matérias-primas usadas nos experimentos.

Methyl esterification of pectin plays a role during plant-pathogen interactions and affects plant resistance to diseases.

Science.gov (United States)

Lionetti, Vincenzo; Cervone, Felice; Bellincampi, Daniela

2012-11-01

The cell wall is a complex structure mainly composed by a cellulose-hemicellulose network embedded in a cohesive pectin matrix. Pectin is synthesized in a highly methyl esterified form and is de-esterified in muro by pectin methyl esterases (PMEs). The degree and pattern of methyl esterification affect the cell wall structure and properties with consequences on both the physiological processes of the plants and their resistance to pathogens. PME activity displays a crucial role in the outcome of the plant-pathogen interactions by making pectin more susceptible to the action of the enzymes produced by the pathogens. This review focuses on the impact of pectin methyl esterification in plant-pathogen interactions and on the dynamic role of its alteration during pathogenesis. Copyright © 2012 Elsevier GmbH. All rights reserved.

Kinetics of microwave assisted extraction of pectin from Balinese orange peel using Pseudo-homogeneous model

Science.gov (United States)

Megawati, Wulansarie, Ria; Faiz, Merisa Bestari; Adi, Susatyo; Sammadikun, Waliyuddin

2018-03-01

The objective of this work was to study the homogeneous kinetics of pectin extraction of Balinese orange peel conducted using Microwave Assisted Extraction (MAE). The experimental data showed that the power increases (180 to 600 W), so that the extraction yield of pectin also increases (12.2 to 30.6 % w/w). Moreover, the extraction time is longer (10, 15, and 20 min) the yield of pectin increases (8.8, 20.2, and 40.5). At time after of 20 min (25 and 30 min), the yield starts to decrease (36.6 and 22.9). This phenomena shows pectin degradation. Therefore, pectin extraction is a series reaction, i.e. extraction and degradation. The calculation result showed that pseudo series homogeneous model can quantitatively describe the extraction kinetics. The kinetic constants can be expressed by Arrhenius equation with the frequency factors of 1.58 × 105 and 2.29 × 105 1/min, while the activation energies are 64,350 and 56,571 J/mole for extraction and degradation, respectively.

Novel banana peel pectin mediated green route for the synthesis of hydroxyapatite nanoparticles and their spectral characterization.

Science.gov (United States)

Gopi, D; Kanimozhi, K; Bhuvaneshwari, N; Indira, J; Kavitha, L

2014-01-24

Hydroxyapatite [HAP, Ca10(PO4)6(OH)2] is the main inorganic component of natural bone and is widely used in various biomedical applications. In this paper, we have reported the synthesis of HAP nanoparticles by banana peel pectin mediated green template method. The pectin extracted from the peels of banana and its various concentrations were exploited in our study to achieve a controlled crystallinity, particle size as well as uniform morphology of HAP. The extracted pectin was characterized by spectral techniques like Fourier transform infrared spectroscopy (FTIR) for the functional group analysis, proton-1 nuclear magnetic resonance spectroscopy ((1)H NMR) and carbon-13 nuclear magnetic resonance spectroscopy ((13)C NMR) for the identification of H and C atoms in the extracted pectin, respectively. The HAP nanoparticles were synthesized using different concentrations of the as-extracted pectin. The purity, crystallinity and morphology of the as-synthesized HAP nanoparticles were evaluated by FTIR, X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDAX) and transmission electron microscopy (TEM), respectively. Moreover the antibacterial activity of HAP nanoparticles was evaluated against the gram positive and negative bacteria like Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively. The experimental results revealed that the HAP nanoparticles synthesized in the presence of an optimized concentration of pectin are pure, low crystalline, spherical and discrete particles with reduced size. Also, the HAP sample derived in the presence of pectin showed an enhanced antibacterial activity than that of the HAP synthesized in the absence of pectin. Hence, the HAP nanoparticles synthesized using pectin as a green template can act as a good biomaterial for biomedical applications. Copyright © 2013 Elsevier B.V. All rights reserved.

Coffee grounds as filler for pectin: Green composites with competitive performances dependent on the UV irradiation.

Science.gov (United States)

Cataldo, Vincenzo Alessandro; Cavallaro, Giuseppe; Lazzara, Giuseppe; Milioto, Stefana; Parisi, Filippo

2017-08-15

Novel composite bioplastics were successfully prepared by filling pectin matrix with treated coffee grounds. The amount of coffee dispersed into the pectin was changed within a wide filler range. The morphology of the pectin/coffee hybrid films was studied by microscopic techniques in order to investigate their mesoscopic structure as well as the sizes distribution of the particles dispersed into the matrix. The micrographs showed that the coffee grounds are uniformly dispersed within the polymeric matrix. The morphological characteristics of the biocomposite films were correlated to their properties, such as wettability, water uptake, thermal behavior and mechanical performances. Dynamic mechanical test were conducted as a function of the humidity conditions. As a general result, a worsening of the mechanical performances was induced by the addition of the coffee grounds into the pectin. An additional UV curing treatment was conducted on the pectin/coffee films with the aim to improve their tensile and viscoelastic features. The cured films showed promising and tunable properties that are dependent on both the filler content and the UV irradiation. In particular, the presence of single coffee particles into the pectin matrix renders the UV curing treatment effective in the enhancement of the elasticity as well as the traction resistance, whereas the cured composite films containing coffee clusters showed only more elastic characteristics. With this study, we fabricated pectin/coffee bioplastics with controlled behavior appealing for specific application within the food packaging. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pectin isolated from prickly pear (Opuntia SSP) modifies LDL metabolism in cholesterol-fed guinea pigs

International Nuclear Information System (INIS)

Fernandez, M.L.; McNamara, D.J.

1990-01-01

The effects of dietary pectin on plasma and hepatic cholesterol (CH) levels, plasma lipoprotein profiles, hepatic 3-hydroxy-3-methylglutaryl Coenzyme A (HMG-CoA) reductase activity, and low density lipoprotein (LDL) binding to hepatic membranes were investigated by feeding 1% pectin to guinea pigs on a high CH diet. Animals were fed either chow + 0.25% CH (HC diet) or the CH diet + 1% prickly pear pectin (HC-P diet) for 25 days. Plasma CH levels were decreased 26% by the HC-P with 33% decreases in LDL and KDL. LDL peak density shifted from 1.040 to 1.055 g/ml with pectin. Hepatic total, free and esterified CH levels were reduced 60, 40 and 85% respectively by the HC-P diet. In contrast, HMG-CoA reductase activity was unaffected. 125 I-LDL binding to hepatic membranes was increased by intake of the HC-P diet compared to the HC diet. The affinity of the apo B/E receptor for LDL was not affected by dietary pectin while the receptor number was increased 1.5-fold in animals on the HC-P diet. These data suggest that the parameters of HC metabolism affected by dietary pectin are consistent with an increased demand on the hepatic CH pools which possibly results from increased fecal excretion of bile acids

Comparison of cell wall metabolism in the pulp of three cultivars of 'Nanfeng' tangerine differing in mastication trait.

Science.gov (United States)

Lei, Ying; Liu, Yong-Zhong; Gu, Qing-Qing; Yang, Xiao-Yan; Deng, Xiu-Xin; Chen, Jin-Yin

2012-02-01

Like sweet orange (Citrus sinensis), tangerine (Citrus reticulata) is another citrus crop grown widely throughout the world. However, whether it shares a common mechanism with sweet orange in forming a given mastication trait is still unclear. In this study, three 'Nanfeng' tangerine cultivars, 'Yangxiao-26' ('YX-26') with inferior mastication trait, elite 'YX-26' with moderate mastication trait and 'Miguang' ('MG') with superior mastication trait, were selected to investigate the formation mechanism of mastication trait. 'MG' had the lowest contents of total pectin, protopectin and lignin and the highest gene expression levels of citrus polygalacturonase (PG) and pectin methylesterase (PME) at the end of fruit ripening, whereas 'YX-26' had the lowest water-soluble pectin (WSP) content, the highest lignin content and the lowest PG and PME expression levels. The contents of cellulose and hemicellulose were similar among the three tangerines. The fruit mastication trait of C. reticulata was determined by the proportions of WSP and protopectin as well as lignin content, not by cellulose and hemicellulose contents. Pectin content could be a major contribution to the feeling of mastication trait, while PG and PME exhibited an important role in forming a given mastication trait according to the present results as well as previous results for C. sinensis. Copyright © 2011 Society of Chemical Industry.

Developmental Localization and Methylesterification of Pectin Epitopes during Somatic Embryogenesis of Banana (Musa spp. AAA)

Science.gov (United States)

Xu, Chunxiang; Zhao, Lu; Pan, Xiao; Šamaj, Jozef

2011-01-01

Background The plant cell walls play an important role in somatic embryogenesis and plant development. Pectins are major chemical components of primary cell walls while homogalacturonan (HG) is the most abundant pectin polysaccharide. Developmental regulation of HG methyl-esterification degree is important for cell adhesion, division and expansion, and in general for proper organ and plant development. Methodology/Principal Findings Developmental localization of pectic homogalacturonan (HG) epitopes and the (1→4)-β-D-galactan epitope of rhamnogalacturonan I (RG-I) and degree of pectin methyl-esterification (DM) were studied during somatic embryogenesis of banana (Musa spp. AAA). Histological analysis documented all major developmental stages including embryogenic cells (ECs), pre-globular, globular, pear-shaped and cotyledonary somatic embryos. Histochemical staining of extracellularly secreted pectins with ruthenium red showed the most intense staining at the surface of pre-globular, globular and pear-shaped somatic embryos. Biochemical analysis revealed developmental regulation of galacturonic acid content and DM in diverse embryogenic stages. Immunodots and immunolabeling on tissue sections revealed developmental regulation of highly methyl-esterified HG epitopes recognized by JIM7 and LM20 antibodies during somatic embryogenesis. Cell walls of pre-globular/globular and late-stage embryos contained both low methyl-esterified HG epitopes as well as partially and highly methyl-esterified ones. Extracellular matrix which covered surface of early developing embryos contained pectin epitopes recognized by 2F4, LM18, JIM5, JIM7 and LM5 antibodies. De-esterification of cell wall pectins by NaOH caused a decrease or an elimination of immunolabeling in the case of highly methyl-esterified HG epitopes. However, immunolabeling of some low methyl-esterified epitopes appeared stronger after this base treatment. Conclusions/Significance These data suggest that both low

Fermentation Process of Cocoa Based on Optimum Condition of Pulp PectinDepolymerization by Endogenous Pectolityc Enzymes

OpenAIRE

Ganda-Putra, G.P; Wrasiati, L.P; Wartini, N.M

2010-01-01

Pulp degradation during cocoa fermentation can be carried out by depolymerization process of pulp pectin using endogenous pectolytic enzymes at optimum condition. The objectives of this research were to study the effect of fermentation process based on optimum condition in terms of temperature and pH of pulp pectin depolymerization using endogenous pectolytic enzymes polygalakturonase (PG) and pectin metyl esterase (PME) and fermentation period in cocoa processing on quality characteristics o...

Modified sugar beet pectin induces apoptosis of colon cancer cells via interaction with the neutral sugar side-chains

Science.gov (United States)

Pectins extracted from a variety of sources and modified with heat and/or pH have previously been shown to exhibit activity towards several cancer cell lines. However, the structural basis for the anti-cancer activity of modified pectin requires clarification. Sugar beet and citrus pectin extracts h...

Mudanças relacionadas ao amaciamento da graviola durante a maturação pós-colheita Changes related to softening of soursop during postharvest maturation

Directory of Open Access Journals (Sweden)

Maria Auxiliadora Coêlho de Lima

2006-12-01

, pectin methylesterase, polygalacturonase and alfa- and beta-galactosidases. There was no significant variation in the soluble pectin content. Weight loss reached 5% in the fifth day, without causing fruit shriveling. Reductions on starch and on total pectin contents occurred in the period of great enzymatic activity, respectively, of amylase and of polygalacturonase, and cell wall beta-galactosidase. The most significant changes on the contents of starch and total pectin, on pectin solubilization and on the activity of the enzymes amylase, pectin methylesterase, polygalacturonase and cell wall beta-galactosidase occurred from the second to the fourth day after harvest.

The Antioxidant Properties of Pectin Fractions Isolated from Vegetables Using a Simulated Gastric Fluid

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Vasily V. Smirnov

2017-01-01

Full Text Available The antioxidant properties of vegetable pectin fractions against intraluminal reactive oxygen species were elucidated in vitro in conjunction with their structural features. The pectin fractions were isolated using a simulated gastric fluid (pH 1.5, pepsin 0.5 g/L, 37°C, 4 h from fresh white cabbage, carrot, onion, and sweet pepper. The fraction from onion was found to inhibit the production of superoxide radicals by inhibiting the xanthine oxidase. The high molecular weight of onion pectin and a large number of galactose residues in its side chains appeared to participate in interaction with xanthine oxidase. All the isolated pectic polysaccharides were found to be associated with protein (2–9% and phenolics (0.5–0.7% as contaminants; these contaminants were shown to be responsible for the antioxidant effect of vegetable pectin fractions against the hydroxyl and 1,1-diphenyl-2-picrylhydrazyl radicals.

Sodium bicarbonate loading limits tubular cast formation independent of glomerular injury and proteinuria in dahl salt-sensitive rats.

Science.gov (United States)

Ray, S C; Patel, B; Irsik, D L; Sun, J; Ocasio, H; Crislip, G R; Jin, C H; Chen, J K; Baban, B; Polichnowski, A J; O'Connor, P M

2018-04-12

Sodium bicarbonate (NaHCO 3 ) slows the decline in kidney function in patients with chronic kidney disease (CKD), yet the mechanisms mediating this effect remain unclear. The Dahl salt-sensitive (SS) rat develops hypertension and progressive renal injury when fed a high salt diet; however, the effect of alkali loading on kidney injury has never been investigated in this model. We hypothesized that 'NaHCO 3 protects from the development of renal injury in Dahl salt-sensitive rats via luminal alkalization which limits the formation of tubular casts, which are a prominent pathological feature in this model. To examine this hypothesis, we determined blood pressure and renal injury responses in Dahl SS rats drinking vehicle (0.1M NaCl) or NaHCO 3 (0.1M) solutions as well as in Dahl SS rats lacking the voltage gated proton channel (Hv1). We found that oral NaHCO 3 reduced tubular NH 4 + production, tubular cast formation and interstitial fibrosis in rats fed a high salt diet for 2 weeks. This effect was independent of changes in blood pressure, glomerular injury or proteinuria and did not associate with changes in renal inflammatory status. We found that null mutation of Hv1 also limited cast formation in Dahl SS rats independent of proteinuria or glomerular injury. As Hv1 is localized to the luminal membrane of TAL, our data, suggest that alkalization of the luminal fluid within this segment limits cast formation in this model. Reduced cast formation, secondary to luminal alkalization within TAL segments may mediate some of the protective effects of alkali loading observed in CKD patients. ©2018 The Author(s).

Yield and quality of pectins extractable from the peels of thai mango cultivars depending on fruit ripeness.

Science.gov (United States)

Sirisakulwat, Suparat; Nagel, Andreas; Sruamsiri, Pittaya; Carle, Reinhold; Neidhart, Sybille

2008-11-26

Pectins, recovered from the peels of four mango ( Mangifera indica L.) cultivars by mimicking industrial techniques, were evaluated in terms of yield, composition, macromolecular properties, and technofunctional quality. Freeze-dried peels of mature-green fruits, after major mesocarp softening, and at full ripeness were extracted using hot acid. The pectins were precipitated in propan-2-ol and their crude yields quantified as alcohol-insoluble substance. Like apple pomace, the dried peels provided hardly acetylated (DAc implied by arabinose/galactose ratios of 8-15 and 33-56 mol/100 mol, respectively. Limited galacturonic acid contents made the mango peel pectins less valuable than commercial apple pectins with regard to gelling capacity and thickening properties. Whereas starch and matrix glycan fragments almost completely degraded during ripening, depolymerization of pectins and galactans was insignificant. Technofunctional properties, modulated by extraction at different pH values, were ascribed to structural differences influencing macromolecular entanglements.

Boron Supply Enhances Aluminum Tolerance in Root Border Cells of Pea (Pisum sativum by Interacting with Cell Wall Pectins

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Xue Wen Li

2017-05-01

Full Text Available Aluminum (Al toxicity is the primary factor limiting crop growth in acidic soils. Boron (B alleviates Al toxicity in plants, which is mainly considered to be due to the formation of Rhamnogalacturonan II-B (RGII-B complexes, which helps to stabilize the cytoskeleton. It is unclear yet whether this is due to the increasing of net negative charges and/or further mechanisms. Kinetics of Al accumulation and adsorption were investigated using entire cells, cell wall and pectin of root border cells (RBCs of pea (Pisum sativum, to reveal the mechanism of B in interacting with alkali-soluble and chelator-soluble pectin for an increased Al tolerance in RBCs. The results show that B could rescue RBCs from Al-induced cell death by accumulating more Al in the cell wall, predominately in alkali-soluble pectin. Boron also promotes Al3+ adsorption and inhibits Al3+ desorption from alkali-soluble pectin. Thus, more Al3+ is immobilized within the alkali-soluble pectin fraction and less in the chelator-soluble pectin, rendering Al3+ less mobile. Boron induces an increase of RG-II (KDO,2-keto-3-deoxyoctonic acid content for forming more borate-RGII complexes, and the decrease of pectin methyl-esterification, thus creates more negative charges to immobilize Al3+ in cell wall pectin. The study provides evidence that abundant B supply enhances the immobilization of Al in alkali-soluble pectin, thus most likely reducing the entry of Al3+ into the symplast from the surroundings.

Characterization of Two Homogalacturonan Pectins with Immunomodulatory Activity from Green Tea

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Huijun Wang

2014-06-01

Full Text Available Two natural homogalacturonan (HG pectins (MW ca. 20 kDa were isolated from green tea based on their immunomodulatory activity. The crude tea polysaccharides (TPS1 and TPS2 were obtained from green tea leaves by hot water extraction and followed by 40% and 70% ethanol precipitation, respectively. Two homogenous water soluble polysaccharides (TPS1-2a and TPS1-2b were obtained from TPS1 after purification with gel permeation, which gave a higher phagocytic effect than TPS2. A combination of composition, methylation and configuration analyses, as well as NMR (nuclear magnetic resonance spectroscopy revealed that TPS1-2a and TPS1-2b were homogalacturonan (HG pectins consisting of a backbone of 1,4-linked α-d-galacturonic acid (GalA residues with 28.4% and 26.1% of carboxyl groups as methyl ester, respectively. The immunological assay results demonstrated that TPS1-2, which consisted mainly of HG pectins, showed phagocytosis-enhancing activity in HL-60 cells.

Reducing the 137Cs-load in the organism of "Chernobyl" children with apple-pectin.

Science.gov (United States)

Nesterenko, V B; Nesterenko, A V; Babenko, V I; Yerkovich, T V; Babenko, I V

2004-01-10

As a complement of standard radioprotective measures, apple-pectin preparations are given, especially in the Ukraine, to reduce the 137Cs uptake in the organism of children. The question has been raised: is oral pectin also useful when children receive radiologically clean food, or does this polysaccharide only act in binding 137Cs in the gut, blocking its intestinal absorption? In this case, pectin would be useless if radiologically clean food could be given. The study was a randomised, double blind placebo-controlled trial comparing the efficacy of a dry and milled apple-extract containing 15-16% pectin with a similar placebo-powder, in 64 children originating from the same group of contaminated villages of the Gomel oblast. The average 137Cs load was of about 30 Bq/kg bodyweight (BW). The trial was conducted during the simultaneous one-month stay in the sanatorium Silver Spring. In this clean radiological environment only radiologically "clean" food is given to the children. The average reduction of the 137Cs levels in children receiving oral pectin powder was 62.6%, the reduction with "clean" food and placebo was 13.9%, the difference being statistically significant (p <0.01). The reduction of the 137Cs load is medically relevant, as no child in the placebo group reached values below 20 Bq/kg BW (which is considered by Bandazhevsky as potentially associated with specific pathological tissue damages), with an average value of 25.8 +/- 0.8 Bq/kg. The highest value in the apple-pectin group was 15.4 Bq/kg, the average value being 11.3 +/- 0.6 Bq/kg BW.

Synthesis and in vitro characterization of entirely S-protected thiolated pectin for drug delivery.

Science.gov (United States)

Hintzen, Fabian; Hauptstein, Sabine; Perera, Glen; Bernkop-Schnürch, Andreas

2013-11-01

The study was aimed to synthesize a thiolated polymer (thiomer) that is resistant to oxidation in solutions above pH 5. In order to protect a pectin-cysteine conjugate against premature oxidation, the thiomer was S-protected by a disulfide connected leaving group. Therefore, 2-mercaptonicotinic acid was first coupled to L-cysteine by a disulfide exchange reaction and the purified product was subsequently attached to pectin by a carbodiimide mediated amid bond formation. The obtained fully S-protected thiolated pectin was in vitro characterized with respect to co- and mucoadhesive properties and stability toward oxidation. The results indicated a 1.8-fold and 2.3-fold enhanced disintegration time at pH 6.8 of the S-protected thiolated pectin (Pec-Cys-MNA) compared to thiolated pectin (Pec-Cys) and unmodified pectin (Pec). Moreover, rheological measurements of polymer/mucus mixtures showed a 1.6-fold (compared to Pec-Cys) and 6.7-fold (compared to Pec) increased dynamic viscosity of Pec-Cys-MNA. On the other hand, in the presence of a strong oxidizing agent such as H2O2 (0.3% v/v), no increase in viscosity of Pec-Cys-MNA could be observed. A 6-month experiment also demonstrated the long-term stability of a liquid formulation based on Pec-Cys-MNA. Further investigations proved that the first time all thiol groups on a thiolated polymer could be protected owing to the novel synthesis. Accordingly, these features may help to develop thiomer based liquid or gel formulations targeting mucosal surfaces such as nasal, ocular or vaginal drug delivery systems. Copyright © 2013 Elsevier B.V. All rights reserved.

Potentiometric titration for determining the composition and stability of metal(II) alginates and pectinates in aqueous solutions

Science.gov (United States)

Kaisheva, N. Sh.; Kaishev, A. Sh.

2015-07-01

The compositions and stabilities of Cu2+, Mn2+, Pb2+, Ca2+, Zn2+, Cd2+, Co2+, and Ni2+ alginates and pectinates are determined in aqueous solutions via titrimetry and potentiometry with calculations performed using Bjerrum's method, the curve intersection technique, and the equilibrium shift method. It is found that the interaction between Cu2+ and polyuronides is a stepwise process and, depending on the ligand concentration and the method of determination, Cu2+ alginate can be characterized by its ML, ML2, and ML3 compositions (where M is the metal ion and L is the structural unit of polyuronide) and stability constants logβ = 2.65, 5.00-5.70, and 7.18-7.80, respectively. The compositions of Cu2+ pectinates are ML and ML2 with logβ = 3.00 and 7.64-7.94, respectively. It is concluded that Pb2+, Ca2+, Mn2+, Zn2+, Cd2+, Co2+, and Ni2+ ions form only alginates and pectinates of ML2 composition with logβ values of 3.45 (Pb2+ alginate), 2.20 (Ca2+ alginate), 1.06 (Mn2+ alginate), 3.51 (Pb2+ pectinate), 2.35 (Ca2+ pectinate), and 1.24 (Mn2+ pectinate). The pectinates are shown to be more stable than the alginates, the most stable compounds being those formed by polyuronides and Cu2+. The least stable are those with Mn2+.

Citrus pectin derived porous carbons as a superior adsorbent toward removal of methylene blue

International Nuclear Information System (INIS)

Zhang, Wenlin; Zhang, Lian Ying; Zhao, Xi Juan; Zhou, Zhiqin

2016-01-01

An adsorbent, citrus pectin derived porous carbons with ultra-high adsorption capacity, rapid adsorption rate and good reusability toward removal of methylene blue, was synthesized by a facile zinc chloride activation approach in this study. The materials hold a great potential for treatment of dye wastewater. - Graphical abstract: Citrus pectin derived porous carbons with ultra-high adsorption capacity, rapid adsorption rate and good reusability toward methylene blue removal. - Highlights: • Citrus pectin derived porous carbons (CPPCs) were synthesized a facile zinc chloride activation approach. • CPPCs had abundant macro/meso/micropores for trapping MB molecules. • CPPCs exhibited ultrahigh adsorption capacity, rapid adsorption rate and good reusability toward removal of MB.

Citrus pectin derived porous carbons as a superior adsorbent toward removal of methylene blue

Energy Technology Data Exchange (ETDEWEB)

Zhang, Wenlin [College of Horticulture and landscape Architecture, Southwest University, Chongqing 400716 (China); Zhang, Lian Ying [Institute for Clean Energy & Advanced Materials, Southwest University, Chongqing 400715 (China); Zhao, Xi Juan [College of Horticulture and landscape Architecture, Southwest University, Chongqing 400716 (China); Key Laboratory of Horticulture Science for Southern Mountainous Regions, Ministry of Education, Chongqing 400715 (China); Zhou, Zhiqin, E-mail: zhouzhiqin@swu.edu.cn [College of Horticulture and landscape Architecture, Southwest University, Chongqing 400716 (China); Key Laboratory of Horticulture Science for Southern Mountainous Regions, Ministry of Education, Chongqing 400715 (China)

2016-11-15

An adsorbent, citrus pectin derived porous carbons with ultra-high adsorption capacity, rapid adsorption rate and good reusability toward removal of methylene blue, was synthesized by a facile zinc chloride activation approach in this study. The materials hold a great potential for treatment of dye wastewater. - Graphical abstract: Citrus pectin derived porous carbons with ultra-high adsorption capacity, rapid adsorption rate and good reusability toward methylene blue removal. - Highlights: • Citrus pectin derived porous carbons (CPPCs) were synthesized a facile zinc chloride activation approach. • CPPCs had abundant macro/meso/micropores for trapping MB molecules. • CPPCs exhibited ultrahigh adsorption capacity, rapid adsorption rate and good reusability toward removal of MB.

Pectin Methylesterification Impacts the Relationship between Photosynthesis and Plant Growth.

Science.gov (United States)

M Weraduwage, Sarathi; Kim, Sang-Jin; Renna, Luciana; C Anozie, Fransisca; D Sharkey, Thomas; Brandizzi, Federica

2016-06-01

Photosynthesis occurs in mesophyll cells of specialized organs such as leaves. The rigid cell wall encapsulating photosynthetic cells controls the expansion and distribution of cells within photosynthetic tissues. The relationship between photosynthesis and plant growth is affected by leaf area. However, the underlying genetic mechanisms affecting carbon partitioning to different aspects of leaf growth are not known. To fill this gap, we analyzed Arabidopsis plants with altered levels of pectin methylesterification, which is known to modulate cell wall plasticity and plant growth. Pectin methylesterification levels were varied through manipulation of cotton Golgi-related (CGR) 2 or 3 genes encoding two functionally redundant pectin methyltransferases. Increased levels of methylesterification in a line over-expressing CGR2 (CGR2OX) resulted in highly expanded leaves with enhanced intercellular air spaces; reduced methylesterification in a mutant lacking both CGR-genes 2 and 3 (cgr2/3) resulted in thin but dense leaf mesophyll that limited CO2 diffusion to chloroplasts. Leaf, root, and plant dry weight were enhanced in CGR2OX but decreased in cgr2/3. Differences in growth between wild type and the CGR-mutants can be explained by carbon partitioning but not by variations in area-based photosynthesis. Therefore, photosynthesis drives growth through alterations in carbon partitioning to new leaf area growth and leaf mass per unit leaf area; however, CGR-mediated pectin methylesterification acts as a primary factor in this relationship through modulation of the expansion and positioning of the cells in leaves, which in turn drive carbon partitioning by generating dynamic carbon demands in leaf area growth and leaf mass per unit leaf area. © 2016 American Society of Plant Biologists. All Rights Reserved.

Effect of citric pectin on beta-carotene bioavailability in rats.

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Zanutto, Márcia E; Jordão Júnior, Alceu A; Meirelles, Mônica S S; Fávaro, Rosa M D; Vannucchi, Hélio

2002-07-01

The effect of citric pectin on the bioavailability of synthetic beta-carotene was studied. Thirty Wistar rats were used, ten animals were sacrificed at the beginning of the experiment and remaining animals were divided into two groups and received the following diets for 30 days: control group (CG)--24 micrograms beta-carotene/g diet + 0% citric pectin; experimental group (EG)--24 micrograms beta-carotene/g diet + 7% citric pectin. Plasma and liver beta-carotene, vitamin A, and retinyl palmitate concentrations were determined by high-performance liquid chromatography (HPLC). Plasma retinol concentration was 1.42 +/- 0.36 mumol/L for CG and 1.10 +/- 0.24 mumol/L for EG (p = 0.1), and plasma beta-carotene concentration was 0.20 +/- 2.51 mumol/L for CG and 0.07 +/- 0.04 mumol/L for EG (p = 0.01). Only traces of retinyl palmitate were detected in CG and none in EG. Retinol did not differ significantly between groups CG and EG, while a significantly higher beta-carotene concentration was observed for CG. Liver concentrations of retinol (CG: 4.90 +/- 2.51 micrograms/g; EG: 2.68 +/- 1.12 micrograms/g), beta-carotene (CG: 0.98 +/- 0.28 microgram/g; EG: 0.11 +/- 0.06 microgram/g), and retinyl palmitate (CG: 95.47 +/- 45.13 micrograms/g, EG: 37.01 +/- 17.20 micrograms/g) differed significantly between groups (p < 0.05), with a lower concentration being observed for EG. We conclude that 7% citric pectin in the rat diet decreases the bioavailability of synthetic beta-carotene, reducing the liver reserves of vitamin A and beta-carotene.

A Proteomic Study of Pectin Degrading Enzymes Secreted by Botrytis cinerea Grown in Liquid Culture

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Shah, Punit; Gutierrez-Sanchez, Gerardo; Orlando, Ron; Bergmann, Carl

2009-01-01

Botrytis cinerea is a pathogenic filamentous fungus which infects more than 200 plant species. The enzymes secreted by B. cinerea play an important role in the successful colonization of a host plant. Some of the secreted enzymes are involved in the degradation of pectin, a major component of the plant cell wall. A total of 126 proteins secreted by B. cinerea were identified by growing the fungus on highly or partially esterified pectin, or on sucrose in liquid culture. Sixty-seven common proteins were identified in each of the growth conditions, of which 50 proteins exhibited a Signal P motif. Thirteen B. cinerea proteins with functions related to pectin degradation were identified in both pectin growth conditions, while only four were identified in sucrose. Our results indicate it is unlikely that the activation of B. cinerea from the dormant state to active infection is solely dependent on changes in the degree of esterification of the pectin component of the plant cell wall. Further, these results suggest that future studies of the B. cinerea secretome in infections of ripe and unripe fruits will provide important information that will describe the mechanisms that the fungus employs to access nutrients and decompose tissues. PMID:19526562

Biocompatible Polyelectrolyte Complex Nanoparticles from Lactoferrin and Pectin as Potential Vehicles for Antioxidative Curcumin.

Science.gov (United States)

Yan, Jing-Kun; Qiu, Wen-Yi; Wang, Yao-Yao; Wu, Jian-Yong

2017-07-19

Polyelectrolyte complex nanoparticles (PEC NPs) were fabricated via electrostatic interactions between positively charged heat-denatured lactoferrin (LF) particles and negatively charged pectin. The obtained PEC NPs were then utilized as curcumin carriers. PEC NPs were prepared by mixing 1.0 mg/mL solutions of heat-denatured LF and pectin at a mass ratio of 1:1 (w/w) in the absence of NaCl at pH 4.50. PEC NPs that were prepared under optimized conditions were spherical in shape with a particle size of ∼208 nm and zeta potential of ∼-32 mV. Hydrophobic curcumin was successfully encapsulated into LF/pectin PEC NPs with high encapsulation efficiency (∼85.3%) and loading content (∼13.4%). The in vitro controlled release and prominent antioxidant activities of curcumin from LF/pectin PEC NPs were observed. The present work provides a facile and fast method to synthesize nanoscale food-grade delivery systems for the improved water solubility, controlled release, and antioxidant activity of hydrophobic curcumin.

Dietary pectin and calcium inhibit colonic proliferation in vivo by differing mechanisms.

Science.gov (United States)

Umar, S; Morris, A P; Kourouma, F; Sellin, J H

2003-12-01

Diet plays an important role in promoting and/or preventing colon cancer; however, the effects of specific nutrients remain uncertain because of the difficulties in correlating epidemiological and basic observations. Transmissible murine colonic hyperplasia (TMCH) induced by Citrobacter rodentium, causes significant hyperproliferation and hyperplasia in the mouse distal colon and increases the risk of subsequent neoplasia. We have recently shown that TMCH is associated with an increased abundance of cellular beta-catenin and its nuclear translocation coupled with up-regulation of its downstream targets, c-myc and cyclin D1. In this study, we examined the effects of two putatively protective nutrients, calcium and soluble fibre pectin, on molecular events linked to proliferation in the colonic epithelium during TMCH. Dietary intervention incorporating changes in calcium [high (1.0%) and low (0.1%)] and alterations in fibre content (6% pectin and fibre-free) were compared with the standard AIN-93 diet (0.5% calcium, 5% cellulose), followed by histomorphometry and immunochemical assessment of potential oncogenes. Dietary interventions did not alter the time course of Citrobacter infection. Both 1.0% calcium and 6% pectin diet inhibited increases in proliferation and crypt length typically seen in TMCH. Neither the low calcium nor fibre-free diets had significant effect. Pectin diet blocked increases in cellular beta-catenin, cyclin D1 and c-myc levels associated with TMCH by 70%, whereas neither high nor low calcium diet had significant effect on these molecules. Diets supplemented with either calcium or pectin therefore, exert anti-proliferative effects in mouse distal colon involving different molecular pathways. TMCH is thus a diet-sensitive model for examining the effect of specific nutrients on molecular characteristics of the pre-neoplastic colonic epithelium.

Enzymatic and phytochemical stabilization of orange-strawberry-banana beverages by high hydrostatic pressure and mild heat.

Science.gov (United States)

Escobedo-Avellaneda, Zamantha; Pérez-Simón, Izaskun; Lavilla-Martín, María; Baranda-González, Ana; Welti-Chanes, Jorge

2017-03-01

A new approach to the use of high hydrostatic pressure is its combination with high and intermediate temperatures applied to obtain safe foods of high quality. The effect of high hydrostatic pressure on color, residual polyphenol oxidase and pectin methylesterase activity, and total phenolic and l-ascorbic acid contents of orange-strawberry-banana beverages was evaluated. Beverages were treated at 500 and 600 MPa at 19-64 ℃ during 2-10 min. The effect of the come up time was also evaluated and results were compared with the untreated and the thermally processed (80 ℃/7 min) products. Untreated beverages had total phenolic content of 210.2±12.3 mg gallic acid/100 g and 19.1 ± 0.6 mg l-ascorbic acid/100 g. For most high hydrostatic pressure treatment conditions, total phenolic content, l-ascorbic acid, and color did not change significantly. Maximum levels of inactivation of polyphenol oxidase and pectin methylesterase were 96.2 and 48% at 600 MPa/64 ℃/10 min, while the thermal treatment led to inactivation of 99.6 and 94.1% of both enzymes, but with negative color changes. l-ascorbic acid content was slightly decreased with the thermal treatment while total phenolic content was not affected. High hydrostatic pressure treatments of beverages at 600 MPa/64 ℃/10 min are recommended to retain maximal total phenolic content and l-ascorbic acid and achieve an acceptable polyphenol oxidase inactivation level.

Effect of sucrose and pectin addition on physical, chemical, thermal and rheological properties of frozen/thawed pineapple pulps

Science.gov (United States)

Conceição, Márcia Cavalcante; Fernandes, Tatiana Nunes; Prado, Mônica Elisabeth Torres; de Resende, Jaime Vilela

2012-09-01

Pectin (0-1.0 g/100 mL) and sucrose (0-20 g/100 mL) were added to pineapple pulp to improve their rheological properties, thermal properties and stability after freezing and thawing processes. The properties of the mixes were characterized before and after freezing and thawing. Samples were frozen at -20°C, and the freeze concentration was evaluated every 60 min. The thawing rate was evaluated at 19°C and quantified by photographic editing and image analysis software. The thawing rates and values for the freeze concentration were leveled out at pectin concentrations above 0.5 g/100 mL pectin, which indicated that pectin functions to maintain structural homogeneity during freezing. In the thawed samples, the plastic viscosity values were leveled out from pectin concentrations (0.25-0.75 g/100 mL) as the sucrose concentration increased when compared to unfrozen samples. The differences between the rheological parameters of the unfrozen and frozen/thawed pulps, the higher yield stress values after thawing were attributed to the size of suspended particles in the pulp. Applications can specify formulations of frozen products containing pectin, where these properties can be handled after thawing the product.

Cacao pod husks as a source of low-methoxyl, highly acetylated pectins able to gel in acidic media.

Science.gov (United States)

Vriesmann, Lúcia Cristina; de Oliveira Petkowicz, Carmen Lúcia

2017-08-01

Cacao pod husks, the main by-product from cocoa production, have been investigated for pectin isolation. In the present study, the rheological properties of two low-methoxyl (LM) pectins isolated from cacao pod husks using different extraction conditions were evaluated. One pectin was obtained from optimized conditions employing aqueous nitric acid as an extractant, and the other one was extracted with boiling water. Pectin gels (0.99% galacturonic acid equivalent, w/w) were prepared at pH 2.5-3.0 in the presence of 60% sucrose (w/w) and subjected to rheological analysis. Dynamic oscillatory experiments at 25°C indicated that better gels were obtained at the lowest pH (2.5). Steady shear measurements revealed a shear-thinning behavior. The apparent viscosities of the samples increased as pH decreased. Gelation with calcium ions was not observed for either of the highly acetylated LM pectins analyzed. The rheological analysis results showed that despite their high acetyl content, LM pectins extracted by different methods from cacao pod husks were able to form gels at low pH under reduced water activity, suggesting a possible application in acidic products. Copyright © 2017 Elsevier B.V. All rights reserved.

The FERONIA Receptor Kinase Maintains Cell-Wall Integrity during Salt Stress through Ca2+ Signaling.

Science.gov (United States)

Feng, Wei; Kita, Daniel; Peaucelle, Alexis; Cartwright, Heather N; Doan, Vinh; Duan, Qiaohong; Liu, Ming-Che; Maman, Jacob; Steinhorst, Leonie; Schmitz-Thom, Ina; Yvon, Robert; Kudla, Jörg; Wu, Hen-Ming; Cheung, Alice Y; Dinneny, José R

2018-03-05

Cells maintain integrity despite changes in their mechanical properties elicited during growth and environmental stress. How cells sense their physical state and compensate for cell-wall damage is poorly understood, particularly in plants. Here we report that FERONIA (FER), a plasma-membrane-localized receptor kinase from Arabidopsis, is necessary for the recovery of root growth after exposure to high salinity, a widespread soil stress. The extracellular domain of FER displays tandem regions of homology with malectin, an animal protein known to bind di-glucose in vitro and important for protein quality control in the endoplasmic reticulum. The presence of malectin-like domains in FER and related receptor kinases has led to widespread speculation that they interact with cell-wall polysaccharides and can potentially serve a wall-sensing function. Results reported here show that salinity causes softening of the cell wall and that FER is necessary to sense these defects. When this function is disrupted in the fer mutant, root cells explode dramatically during growth recovery. Similar defects are observed in the mur1 mutant, which disrupts pectin cross-linking. Furthermore, fer cell-wall integrity defects can be rescued by treatment with calcium and borate, which also facilitate pectin cross-linking. Sensing of these salinity-induced wall defects might therefore be a direct consequence of physical interaction between the extracellular domain of FER and pectin. FER-dependent signaling elicits cell-specific calcium transients that maintain cell-wall integrity during salt stress. These results reveal a novel extracellular toxicity of salinity, and identify FER as a sensor of damage to the pectin-associated wall. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Blends of jackfruit seed starch-pectin in the development of mucoadhesive beads containing metformin HCl.

Science.gov (United States)

Nayak, Amit Kumar; Pal, Dilipkumar

2013-11-01

In this work, calcium pectinate-jackfruit (Artocarpus heterophyllus Lam.) seed starch (JFSS) mucoadhesive beads containing metformin HCl were developed through ionotropic-gelation. Effects of pectin and JFSS amounts on drug encapsulation efficiency (DEE), and cumulative drug release after 10 h (R10 h) were optimized using 3(2) factorial design. The optimized calcium pectinate-JFSS beads containing metformin HCl showed DEE of 94.11 ± 3.92%, R10 h of 48.88 ± 2.02%, and mean diameter of 2.06 ± 0.20 mm. The in vitro drug release from these beads was followed controlled-release (zero-order) pattern with super case-II transport mechanism. The beads were also characterized by SEM and FTIR. The pH of test mediums was found critical for swelling and mucoadhesion of these beads. The optimized calcium pectinate-JFSS beads also exhibited good mucoadhesivity and significant hypoglycemic effect in alloxan-induced diabetic rats over prolonged period after oral administration. Copyright © 2013 Elsevier B.V. All rights reserved.

Unavoidable food supply chain waste: acid-free pectin extraction from mango peel via subcritical water.

Science.gov (United States)

Xia, H; Matharu, A S

2017-09-21

Mango peel is the major by-product of mango processing, and compromises 7-24% of the total mango weight. In this study, pectin was extracted from mango peel waste by using subcritical water extraction (SWE) in the absence of mineral acid. A highest yield of 18.34% was achieved from the Kesar variety and the pectin was characterised using ATR-IR spectroscopy, TGA and 13 C solid-state NMR spectroscopy to confirm the structure. The degree of esterification (DE) of the pectin was analysed with both titrimetry and 13 C solid-state NMR spectroscopy, and a high DE (>70%) was observed for all three varieties (Keitt, Sindhri and Kesar). This is the first report on acid-free subcritical water extraction of pectin from mango peel, which provides a green route for the valorisation of mango peel waste and contributes to a source of biobased materials and chemicals for a sustainable 21 st century.

Effect of pectin extracted from citrus pulp on digesta characteristics and nutrient digestibility in broilers chickens

Directory of Open Access Journals (Sweden)

Vanessa Karla Silva

2013-08-01

Full Text Available The experiment was carried out to evaluate the effects of continuous ingestion of pectin on intestinal viscosity, intestinal transit time, excreta moisture content, nutrient digestibility and energy metabolism of broilers at starter and growth phases. We used 240 one-day-old Cobb male broiler chicks, distributed in a completely randomized experimental design. Treatments consisted of four concentrations of pectin (0, 10, 30 and 50 g kg-1 with six replicates of 10 birds each. The ingestion of pectin supplied in the feed by broilers at the starter phase increased intestinal viscosity and intestinal transit time, reduced excreta moisture, improved the use of apparent metabolizable energy, nitrogen-corrected apparent metabolizable energy, coefficient of apparent metabolizability, coefficient of nitrogen-corrected apparent metabolizability, apparent digestibility coefficient of crude protein and organic matter; worsened calcium utilization and coefficients of apparent digestibility of dry matter; and did not influence the coefficients of apparent digestibility of crude fat, ash and phosphorus. Pectin ingestion during the growth phase increased intestinal viscosity and apparent digestibility coefficients of ash and organic matter, but decreased the dry matter, crude fat, crude protein and calcium. Intestinal transit time, energy metabolism and apparent digestibility coefficient of crude protein showed quadratic behavior according to pectin levels in the feed. Therefore, pectin ingestion by broilers at the starter phase increases intestinal viscosity and intestinal transit time, reduces excreta moisture and improves energy utilization, whereas at the growth phase nutrient digestibility is decreased.

The role of cell walls and pectins in cation exchange and surface area of plant roots.

Science.gov (United States)

Szatanik-Kloc, A; Szerement, J; Józefaciuk, G

2017-08-01

We aimed to assess role of cell walls in formation of cation exchange capacity, surface charge, surface acidity, specific surface, water adsorption energy and surface charge density of plant roots, and to find the input of the cell wall pectins to the above properties. Whole roots, isolated cell walls and the residue after the extraction of pectins from the cell walls of two Apiaceae L. species (celeriac and parsnip) were studied using potentiometric titration curves and water vapor adsorption - desorption isotherms. Total amount of surface charge, as well as the cation exchange capacity were markedly higher in roots than in their cell walls, suggesting large contribution of other cell organelles to the binding of cations by the whole root cells. Significantly lower charge of the residues after removal of pectins was noted indicating that pectins play the most important role in surface charge formation of cell walls. The specific surface was similar for all of the studied materials. For the separated cell walls it was around 10% smaller than of the whole roots, and it increased slightly after the removal of pectins. The surface charge density and water vapor adsorption energy were the highest for the whole roots and the lowest for the cell walls residues after removal of pectins. The results indicate that the cell walls and plasma membranes are jointly involved in root ion exchange and surface characteristics and their contribution depends upon the plant species. Copyright © 2017 Elsevier GmbH. All rights reserved.

Efficacy of pectin solution for preventing gastro-esophageal reflux events in patients with percutaneous endoscopic gastrostomy.

Science.gov (United States)

Adachi, Kyoichi; Furuta, Kenji; Aimi, Masahito; Fukazawa, Kousuke; Shimura, Shino; Ohara, Shunji; Nakata, Shuji; Inoue, Yukiko; Ryuko, Kanji; Ishine, Junichi; Katoh, Kyoko; Hirata, Toshiaki; Ohhata, Shuzo; Katoh, Setsushi; Moriyama, Mika; Sumikawa, Masuko; Sanpei, Mari; Kinoshita, Yoshikazu

2012-05-01

The aim of this study was to determine the efficacy of pectin solution, which increases the viscosity of liquid nutrient, for prevention of gastro-esophageal reflux in comparison with half-solid nutrient. The subjects were 10 elderly patients undergoing percutaneous endoscopic gastrostomy feeding. Twenty-four-hour esophageal multichannel intraluminal impedance and pH testing was performed during intake of half-solid nutrient and a combination of pectin solution and liquid nutrient. During 4 h after delivery, there was no significant difference in the total number of gastro-esophageal reflux events between the feeding of the half-solid nutrient and the combination of pectin solution and liquid nutrient (5.7 ± 1.2 vs 5.3 ± 1.0/4 h). Acidic reflux after delivery of the half-solid nutrient was significantly more frequent than that after delivery of the combination of pectin solution and liquid nutrient (80.7% vs 60.4%, p = 0.018). The incidence of gastro-esophageal reflux reaching the upper portion of the esophagus tended to be higher during delivery of the half-solid nutrient than during delivery of the combination of pectin solution and liquid nutrient (47.4% vs 34.0%, p = 0.153). In conclusion, the usage of pectin solution combined with liquid nutrient is effective for preventing acidic gastro-esophageal reflux and gastro-esophageal reflux reaching the upper portion of the esophagus.

Effects of temperature, ultraviolet radiation and pectin methyl esterase on aerobic methane release from plant material.

Science.gov (United States)

Bruhn, D; Mikkelsen, T N; Obro, J; Willats, W G T; Ambus, P

2009-11-01

This study examines the effects of different irradiance types on aerobic methane (CH(4)) efflux rates from terrestrial plant material. Furthermore, the role of the enzyme pectin methyl esterase (PME) on CH(4) efflux potential was also examined. Different types of plant tissue and purified pectin were incubated in glass vials with different combinations of irradiation and/or temperature. Purified dry pectin was incubated in solution, and with or without PME. Before and after incubation, the concentration of CH(4) was measured with a gas chromatograph. Rates of CH(4) emission were found to depend exponentially on temperature and linearly on UV-B irradiance. UV-B had a greater stimulating effect than UV-A, while visible light had no effect on emission rates. PME was found to substantially reduce the potential for aerobic CH(4) emissions upon demethylation of pectin.

Application of Response Surface Methodology in the Preparation of Pectin-Caseinate Nanocomplexes for Potential Use as Nutraceutical Formulation: A Statistical Experimental Design Analysis

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Sajedeh Bahrani

2018-03-01

Full Text Available Background: The formation of electrostatic complexes between two types of biopolymers, sodium Caseinate (a derivative from most abundant milk protein and Pectin (a natural hetro polysaccharide, was studied as a function of biopolymers concentrations and pH of solutions (3.9- 4.3. Method: The size and morphology of the resulted complexes were investigated by using of laser light scattering and transmission electron microscopy, respectively. Response surface methodology (A three-factor, three levels Box-Behnken design was used for the optimization procedure with pH, pectin and sodium Caseinate concentrations as independent variables. Particle size and polydispersity index of nanocomplexes were considered as dependent variables. Results: Negatively charged nanocomplexes were produced below the isoelectric point of protein (5.4, at pH 4.1 with a suitable colloidal stability and average particle size of about 100 nm. It was found that the particle size of nanocomplexes could be controlled by changing in variables. Conclusion: In conclusion response surface methodology are simple, rapid and beneficial approach for preparation, optimization and investigation of the effect of independent variables on the properties of products.

Use of 3-D modeling in the early development phase of pectin tablets

Directory of Open Access Journals (Sweden)

Linda Salbu

2012-03-01

Full Text Available This study examines the contribution of a 3-D model in an early development of pectin tablets. The aim of this work was to extract as much information of the compression behavior from as few tablets as possible. Pectins with various degrees of methoxylation (DM were studied (4%-72%. The compressibility was evaluated using classic “in-die” Heckel and Kawakita analyses in addition to the 3-D modeling. For validation purposes well-known reference materials were included. 3-D modeling applied to data of single tablets yielded some information on their compressibility. When several tablets with different maximum relative densities were included, no additional information was obtained through classic evaluation. However, the 3-D model provided additional information through the shape of the 3-D parameter plot. Pectins with a DM >= 25% consolidated predominantly by elastic deformation similarly to the 3-D parameter plot of pregelatinized starch (PGS. The 3-D analysis also suggests some degree of fragmentation and, for some of the low-methoxylated pectins (DM <= 10%, viscoelastic deformation. This study showed that by applying 3-D modeling it is possible to differentiate between elastic and viscoelastic materials for tablets with different relative density values.

Osteoblastic response to pectin nanocoating on titanium surfaces

Energy Technology Data Exchange (ETDEWEB)

Gurzawska, Katarzyna, E-mail: kagu@sund.ku.dk [Research Center for Ageing and Osteoporosis, Departments of Medicine and Diagnostics, Copenhagen University Hospital Glostrup, Ndr. Ringvej 57, 2600 Glostrup (Denmark); Institute of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Nørre Allé 20, 2200 Copenhagen N (Denmark); Svava, Rikke [Department of Plant Environment Sciences, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Copenhagen Center for Glycomics, Institute for Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N (Denmark); Yihua, Yu; Haugshøj, Kenneth Brian [Microtechnology and Surface Analysis, Danish Technological Institute, Gregersensvej 8, 2630 Taastrup (Denmark); Dirscherl, Kai [Dansk Fundamental Metrologi A/S, Matematiktorvet 307, 2800 Lyngby (Denmark); Levery, Steven B. [Copenhagen Center for Glycomics, Institute for Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N (Denmark); Byg, Inge [Department of Plant Environment Sciences, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Damager, Iben [Novozymes A/S, Krogshoejvej 36, 2880 Bagsvaerd (Denmark); Nielsen, Martin W. [Department of Systems Biology, Technical University of Denmark, Matematiktorvet, Building 301, Kgs. Lyngby DK-2800 (Denmark); Jørgensen, Bodil [Department of Plant Environment Sciences, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Jørgensen, Niklas Rye [Research Center for Ageing and Osteoporosis, Departments of Medicine and Diagnostics, Copenhagen University Hospital Glostrup, Ndr. Ringvej 57, 2600 Glostrup (Denmark); and others

2014-10-01

Osseointegration of titanium implants can be improved by organic and inorganic nanocoating of the surface. The aim of our study was to evaluate the effect of organic nanocoating of titanium surface with unmodified and modified pectin Rhamnogalacturonan-Is (RG-Is) isolated from potato and apple with respect to surface properties and osteogenic response in osteoblastic cells. Nanocoatings on titanium surfaces were evaluated by scanning electron microscopy, contact angle measurements, atomic force microscopy, and X-ray photoelectron spectroscopy. The effect of coated RG-Is on cell adhesion, cell viability, bone matrix formation and mineralization was tested using SaOS-2 cells. Nanocoating with pectin RG-Is affected surface properties and in consequence changed the environment for cellular response. The cells cultured on surfaces coated with RG-Is from potato with high content of linear 1.4-linked galactose produced higher level of mineralized matrix compared with control surfaces and surfaces coated with RG-I with low content of linear 1.4-linked galactose. The study showed that the pectin RG-Is nanocoating not only changed chemical and physical titanium surface properties, but also specific coating with RG-Is containing high amount of galactan increased mineralized matrix formation of osteoblastic cells in vitro. - Highlights: • Surface nanocoating with plant-derived Rhamnogalacturonan-I (RG-I) is proposed. • Titanium surface became more hydrophilic after RG-Is nanocoating. • RG-Is with high galactose content resulted in high level of mineralized matrix. • RG-I is a new candidate for improvement of bone healing and osseointegration.

Identification of Protein-Protein Interactions Involved in Pectin Biosynthesis in the golgi Apparatus

DEFF Research Database (Denmark)

Lund, Christian Have

for instance as food additives, nutraceutical, for paper and energy production. Pectin is a cell wall glycan that crucial for every plant growing on land. Pectin is said to be one of the most complex glycans on earth and it is hypothesized that at least 67 enzymatic reactions are involved in its biosynthesis......The plant cell wall surrounds every plant cell and is an essential component that is involved in diverse functions including plant development, morphology, resistance towards plant pathogens etc. The plant cell wall is not only important for the plant. The cell wall has many industrial applications...... the diverse pectin structures for industrial, agronomic and biomedical uses. Increasing evidence suggests that complex formation is important in governing functional coordination of proteins involved in cell wall biosynthesis. In Arabidopsis thaliana, a homogalacturonan (HG) synthase core complex between...

From waste to high-value product: Jackfruit peel derived pectin/apatite bionanocomposites for bone healing applications.

Science.gov (United States)

Govindaraj, Dharman; Rajan, Mariappan; Hatamleh, Ashraf A; Munusamy, Murugan A

2018-01-01

Public requirements encouraged by the current asset framework drive industry to expand its general effectiveness by enhancing existing procedures or finding new uses for waste. Thus, the aim of this study was the isolation, fabrication, and characterization of pectin derived from jackfruit (Artocarpus heterophyllus) peels and the generation of hybrid of pectin (P)/apatite (HA) (P/HA) bionanocomposites. In this process, the natural pectin polymer derived from the peel of jackfruits was used in different concentrations for the fabrication of HA bionanocomposites. Characterization of the isolated pectin and bionanocomposites samples was performed with 1 H NMR and 13 C NMR, FTIR, XRD, SEM-EDX, and HR-TEM. Cytocompatibility, ALP, fibroblast stem cells, anti-inflammatory and cell adhesion testing of the fabricated bionanocomposites was showed good biocompatibility. Our results signify that the fabricated bionanocomposites might be applicable as bone graft materials. Copyright © 2017 Elsevier B.V. All rights reserved.

A Novel Pectin Material: Extraction, Characterization and Gelling Properties

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Agustin Rascón-Chu

2010-09-01

Full Text Available A novel pectin was acid extracted from chickpea husk (CHP. CHP presented a 67% (w/w of galacturonic acid, an intrinsic viscosity of 374 mL/g and a viscosimetric molecular weight of 110 kDa. Fourier transform infrared spectroscopy spectrum of CHP indicated a degree of esterification of about 10%. The CHP-calcium system formed ionic gels with a storage (G’ modulus of 40 Pa and gel set time (G’ > G’’ of 3 min at 1% (w/v, and a G’ of 131 Pa and gel set time of 1 min at 2% (w/v. The G’ of CHP gels was not greatly affected by temperature. The results attained suggest that chickpea husk can be a potential source of a gelling pectin material.

The Effect of Antioxidant Polysaccharide Based Coatings on Optimum Immersion Time, Vitamin C Content and Salt Adsorption of Quince Cylinders during Osmotic Dehydration

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M. Akbarian

2015-09-01

Full Text Available In this study, the effects of carboxymethyl cellulose-low methyl pectin based edible coatings containing ascorbic acid antioxidant were investigated on optimum immersion time during osmotic dehydration of quince sheets. The selection of coating type was based on natural composition of fruits peel, (i.e cellulose and pectin and the osmotic solutions were formulated on the basis of natural ingredients in fruits (fructose, citric acid and calcium ions. The results showed that solid gain trends have been incremental until 240 min in both coating types however, the coated samples showed lower solid gain in all testing times. The optimum immersion time was found to be 180 min based on the water loss (W.L, solids gain (S.G, process efficiency index and weight reduction (W. R. In next stage, the absorption of salt and citric acid from osmotic solution and loss of vitamin C from quince cylinders (dried by hot air were measured. Absorption of salt and citric acid in the coated samples was smaller than the non-coated samples and coated and osmotic quince cylinders indicated smaller vitamin C losses than the uncoated and non-osmotic samples.

Sequence analysis and overexpression of a pectin lyase gene (pel1) from Aspergillus oryzae KBN616.

Science.gov (United States)

Kitamoto, N; Yoshino-Yasuda, S; Ohmiya, K; Tsukagoshi, N

2001-01-01

A gene (pel1) encoding pectin lyase (Pel1) was isolated from a shoyu koji mold, Aspergillus oryzae KBN616, and characterized. The structural gene comprised 1,196 bp with a single intron. The ORF encoded 381 amino acids with a signal peptide of 20 amino acids. The deduced amino acid sequence showed high similarity to those of Aspergillus niger pectin lyases and Glomerella cingulata PnlA. The pel1 gene was successfully overexpressed under the promoter of the A. oryzae TEF1 gene. The molecular mass of the recombinant pectin lyase substantially coincided with that calculated based on nucleotide sequence.

Sequential extraction of flavonoids and pectin from yellow passion fruit rind using pressurized solvent or ultrasound.

Science.gov (United States)

de Souza, Caroline G; Rodrigues, Tigressa Hs; E Silva, Lorena Ma; Ribeiro, Paulo Rv; de Brito, Edy S

2018-03-01

Passion fruit rind (PFR) represents 90% of the total fruit weight and is wasted during juice processing. Passion fruit rind is known to contain flavonoids and pectin. An alternative use for this fruit juice industrial residue is to obtain these compounds. This study aimed to verify the influence of pressurized solvent extraction (PSE) or ultrasound assisted extraction (UAE) of flavonoid and pectin in a sequential process. The PSE using ethanol at 60:40 (v/v) yielded a total polyphenol content of 4.67 g GAE kg -1 PFR, orientin-7-O-glucoside (1.57 g kg -1 PFR) and luteolin-6-C-glucoside (2.44 g kg -1 PFR). Pectin yield was 165 g kg -1 PFR, either in PSE or UAE. Pectin characterization indicates that the pectic structure has basically homogalacturonans and galacturonate followed by a galacturonic acid ester unit, with methylation degree of 70%. With this study it can be concluded that mixtures of alcohols with water favor the extraction of bioactive compounds of passion fruit peel. Both PSE and UAE were effective in sequentially extracting flavonoids and pectin. The preferred solvent is ethanol due to its lower toxicity. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Colocalization of low-methylesterified pectins and Pb deposits in the apoplast of aspen roots exposed to lead

International Nuclear Information System (INIS)

Rabęda, Irena; Bilski, Henryk; Mellerowicz, Ewa J.; Napieralska, Anna; Suski, Szymon; Woźny, Adam; Krzesłowska, Magdalena

2015-01-01

Low-methylesterified homogalacturonans have been suggested to play a role in the binding and immobilization of Pb in CW. Using root apices of hybrid aspen, a plant with a high phytoremediation potential, as a model, we demonstrated that the in situ distribution pattern of low-methylesterified homogalacturonan, pectin epitope (JIM5-P), reflects the pattern of Pb occurrence. The region which indicated high JIM5-P level corresponded with “Pb accumulation zone”. Moreover, JIM5-P was especially abundant in cell junctions, CWs lining the intercellular spaces and the corners of intercellular spaces indicating the highest accumulation of Pb. Furthermore, JIM5-P and Pb commonly co-localized. The observations indicate that low-methylesterified homogalacturonan is the CW polymer that determines the capacity of CW for Pb sequestration. Our results suggest a promising directions for CW modification for enhancing the efficiency of plant roots in Pb accumulation, an important aspect in the phytoremediation of soils contaminated with trace metals. - Highlights: • Co-localization of low-methylesterified pectins and Pb was analysed in situ. • The pattern of Pb accumulation matched low-methylesterified pectins distribution. • Low-methylesterified pectins and Pb commonly co-localized in cell walls. • Low-methylesterified pectins revealed an important compound in Pb sequestration. • We suggest a new direction in enhancing plant efficiency for phytoremediation. - The distribution of lead in developing tissues of aspen root tips exposed to short-term lead treatment mimics the distribution of low-methylesterified pectin epitope

Technique of optimum extraction of pectin from sour orange peels and its chemical evaluation

International Nuclear Information System (INIS)

Abid, H.; Hussain, A.; Ali, J.

2009-01-01

The extraction of pectin from sour orange peels and effect of pH, temperature, extraction time on the yield and quality of pectin was studied. The extracting reagent was 0.1 N sulphuric acid and variables were pH (1.5, 2.5 and 3.5), extraction time (30, 60 and 120 minutes) and temperature (70 degree C, 80 degree C arid 90 degree C). These variables were significantly affected the extraction of pectin. The best yield (16.10 %) was obtained on soaking the finely ground peels in the sulphuric acid solution of pH, 25 at 80 degree C for 120 minutes. Anhydrogalacturonic acid, methoxyl content were 7310 % and 9.93 %, respectively, while equivalent weight value 945 was obtained by using pH, 2.5 at 80 degree C for 120 minutes. (author)

Analysis and optimization of flocculation activity and turbidity reduction in kaolin suspension using pectin as a biopolymer flocculant.

Science.gov (United States)

Ho, Y C; Norli, I; Alkarkhi, Abbas F M; Morad, N

2009-01-01

The performance of pectin in turbidity reduction and the optimum condition were determined using Response Surface Methodology (RSM). The effect of pH, cation's concentration, and pectin's dosage on flocculating activity and turbidity reduction was investigated at three levels and optimized by using Box-Behnken Design (BBD). Coagulation and flocculation process were assessed with a standard jar test procedure with rapid and slow mixing of a kaolin suspension (aluminium silicate), at 150 rpm and 30 rpm, respectively, in which a cation e.g. Al(3+), acts as coagulant, and pectin acts as the flocculant. In this research, all factors exhibited significant effect on flocculating activity and turbidity reduction. The experimental data and model predictions well agreed. From the 3D response surface graph, maximum flocculating activity and turbidity reduction are in the region of pH greater than 3, cation concentration greater than 0.5 mM, and pectin dosage greater than 20 mg/L, using synthetic turbid wastewater within the range. The flocculating activity for pectin and turbidity reduction in wastewater is at 99%.

Immobilization of flavan-3-ols onto sensor chips to study their interactions with proteins and pectins by SPR

Energy Technology Data Exchange (ETDEWEB)

Watrelot, Aude A., E-mail: aude.watrelot@avignon.inra.fr [INRA, UMR408 Sécurité et Qualité des Produits d’Origine Végétale, Domaine St Paul, Site Agroparc, 84914 Avignon (France); Université d’Avignon, UMR408 Sécurité et Qualité des Produits d' Origine Végétale, F-84000 Avignon (France); Tran, Dong Tien [Université de Bordeaux, Institut des Sciences Moléculaires (UMR-CNRS 5255), 351 cours de la Libération, 33405 Talence (France); Institut Européen de Chimie et Biologie (IECB), 2 rue Robert Escarpit, 33607 Pessac (France); Buffeteau, Thierry [Université de Bordeaux, Institut des Sciences Moléculaires (UMR-CNRS 5255), 351 cours de la Libération, 33405 Talence (France); Deffieux, Denis [Université de Bordeaux, Institut des Sciences Moléculaires (UMR-CNRS 5255), 351 cours de la Libération, 33405 Talence (France); Institut Européen de Chimie et Biologie (IECB), 2 rue Robert Escarpit, 33607 Pessac (France); and others

2016-05-15

Highlights: • Flavanol-macromolecule interactions were determined using SPR. • Flavanols were chemically modified with a linker bearing a thiol group. • Flavanols were immobilized onto a carboxymethyl dextran surface. • Citrus pectin interacted more with flavanols than apple pectin. • Epicatechin interacted more with BSA than flavanol oligomer. - Abstract: Interactions between plant polyphenols and biomacromolecules such as proteins and pectins have been studied by several methods in solution (e.g. isothermal titration calorimetry, dynamic light scattering, nuclear magnetic resonance and spectrophotometry). Herein, these interactions were investigated in real time by Surface Plasmon Resonance (SPR) analysis after immobilization of flavan-3-ols onto a sensor chip surface. (−)-epicatechin, (+)-catechin and flavan-3-ol oligomers with an average degree of polymerization of 2 and 8 were chemically modified using N-(2-(tritylthio)ethyl)propiolamide in order to introduce a spacer unit onto the catecholic B ring. Modified flavan-3-ols were then immobilized onto a carboxymethylated dextran surface (CM5). Immobilization was validated and further verified by evaluating flavan-3-ol interaction with bovine serum albumin (BSA), poly-L-proline or commercial pectins. BSA was found to have a stronger association with monomeric flavan-3-ols than oligomers. SPR analysis of selected flavan-3-ols immobilized onto CM5 sensor chips showed a stronger association for citrus pectins than apple pectins, regardless of flavan-3-ol degree of polymerization.

Immobilization of flavan-3-ols onto sensor chips to study their interactions with proteins and pectins by SPR

International Nuclear Information System (INIS)

Watrelot, Aude A.; Tran, Dong Tien; Buffeteau, Thierry; Deffieux, Denis

2016-01-01

Highlights: • Flavanol-macromolecule interactions were determined using SPR. • Flavanols were chemically modified with a linker bearing a thiol group. • Flavanols were immobilized onto a carboxymethyl dextran surface. • Citrus pectin interacted more with flavanols than apple pectin. • Epicatechin interacted more with BSA than flavanol oligomer. - Abstract: Interactions between plant polyphenols and biomacromolecules such as proteins and pectins have been studied by several methods in solution (e.g. isothermal titration calorimetry, dynamic light scattering, nuclear magnetic resonance and spectrophotometry). Herein, these interactions were investigated in real time by Surface Plasmon Resonance (SPR) analysis after immobilization of flavan-3-ols onto a sensor chip surface. (−)-epicatechin, (+)-catechin and flavan-3-ol oligomers with an average degree of polymerization of 2 and 8 were chemically modified using N-(2-(tritylthio)ethyl)propiolamide in order to introduce a spacer unit onto the catecholic B ring. Modified flavan-3-ols were then immobilized onto a carboxymethylated dextran surface (CM5). Immobilization was validated and further verified by evaluating flavan-3-ol interaction with bovine serum albumin (BSA), poly-L-proline or commercial pectins. BSA was found to have a stronger association with monomeric flavan-3-ols than oligomers. SPR analysis of selected flavan-3-ols immobilized onto CM5 sensor chips showed a stronger association for citrus pectins than apple pectins, regardless of flavan-3-ol degree of polymerization.

Growth platform-dependent and -independent phenotypic and metabolic responses of Arabidopsis and its halophytic relative, Eutrema salsugineum, to salt stress.

Science.gov (United States)

Kazachkova, Yana; Batushansky, Albert; Cisneros, Aroldo; Tel-Zur, Noemi; Fait, Aaron; Barak, Simon

2013-07-01

Comparative studies of the stress-tolerant Arabidopsis (Arabidopsis thaliana) halophytic relative, Eutrema salsugineum, have proven a fruitful approach to understanding natural stress tolerance. Here, we performed comparative phenotyping of Arabidopsis and E. salsugineum vegetative development under control and salt-stress conditions, and then compared the metabolic responses of the two species on different growth platforms in a defined leaf developmental stage. Our results reveal both growth platform-dependent and -independent phenotypes and metabolic responses. Leaf emergence was affected in a similar way in both species grown in vitro but the effects observed in Arabidopsis occurred at higher salt concentrations in E. salsugineum. No differences in leaf emergence were observed on soil. A new effect of a salt-mediated reduction in E. salsugineum leaf area was unmasked. On soil, leaf area reduction in E. salsugineum was mainly due to a fall in cell number, whereas both cell number and cell size contributed to the decrease in Arabidopsis leaf area. Common growth platform-independent leaf metabolic signatures such as high raffinose and malate, and low fumarate contents that could reflect core stress tolerance mechanisms, as well as growth platform-dependent metabolic responses were identified. In particular, the in vitro growth platform led to repression of accumulation of many metabolites including sugars, sugar phosphates, and amino acids in E. salsugineum compared with the soil system where these same metabolites accumulated to higher levels in E. salsugineum than in Arabidopsis. The observation that E. salsugineum maintains salt tolerance despite growth platform-specific phenotypes and metabolic responses suggests a considerable degree of phenotypic and metabolic adaptive plasticity in this extremophile.

Reducing the Salt Added to Takeaway Food: Within-Subjects Comparison of Salt Delivered by Five and 17 Holed Salt Shakers in Controlled Conditions.

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Louis Goffe

Full Text Available To determine if the amount of salt delivered by standard salt shakers commonly used in English independent takeaways varies between those with five and 17 holes; and to determine if any differences are robust to variations in: the amount of salt in the shaker, the length of time spent shaking, and the person serving.Four laboratory experiments comparing the amount of salt delivered by shakers. Independent variables considered were: type of shaker used (five or 17 holes, amount of salt in the shaker before shaking commences (shaker full, half full or nearly empty, time spent shaking (3s, 5s or 10s, and individual serving.Controlled, laboratory, conditions.A quota-based convenience sample of 10 participants (five women aged 18-59 years.Amount of salt delivered by salt shakers.Across all trials, the 17 holed shaker delivered a mean (SD of 7.86g (4.54 per trial, whilst the five holed shaker delivered 2.65g (1.22. The five holed shaker delivered a mean of 33.7% of the salt of the 17 holed shaker. There was a significant difference in salt delivered between the five and 17 holed salt shakers when time spent shaking, amount of salt in the shaker and participant were all kept constant (p<0.001. This difference was robust to variations in the starting weight of shakers, time spent shaking and participant shaking (pssalt shakers have the potential to reduce the salt content of takeaway food, and particularly food from Fish & Chip shops, where these shakers are particularly used. Further research will be required to determine the effects of this intervention on customers' salt intake with takeaway food and on total dietary salt intake.

Physicochemical and in vitro antioxidant properties of pectin extracted from hot pepper (Capsicum annuum L. var. acuminatum (Fingerh.)) residues with hydrochloric and sulfuric acids.

Science.gov (United States)

Xu, Honggao; Tai, Kedong; Wei, Tong; Yuan, Fang; Gao, Yanxiang

2017-11-01

Transformation of hot pepper residues to value-added products with concomitant benefits on environmental pollution would be of great value to capsicum oleoresin manufacturers. Pectin, a soluble dietary fiber with multiple functions, from hot pepper residues was investigated in this study. The extraction of hot pepper pectin using hydrochloric acid was first optimized using response surface methodology (RSM). The most efficient parameters for maximum hot pepper pectin yield (14.63%, dry basis) were a pH of 1.0, a temperature of 90 °C, an extraction time of 2 h and a liquid-to-solid ratio of 20 L g -1 . The pectin was mainly composed of uronic acids, and the major neutral sugars were galactose and glucose. The structure of hot pepper pectin was characterized by homogalacturonan and rhamnogalacturonan I elements. The physicochemical properties of hot pepper pectin extracted by sulfuric acid and hydrochloric acid were further investigated. The content of protein and degree of esterification in hot pepper pectin extracted with sulfuric acid solution (SP) were higher (P hot pepper pectin, hot pepper residues would be a new source to obtain pectin, and SP would be more preferred than HP. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

THE INFLUENCE OF THE EXTRACTION TEMPERATURE ON THE RENDEMENT AND PECTIN METHOXYL CONTENTS OF WATERHYACINTH (Eichornia crassipes (Mart Solms

Directory of Open Access Journals (Sweden)

Ika Daniarsari

2010-06-01

Full Text Available The purpose of this research is to find out the influence of the extraction temperature on the rendement and pectin methoxyl contents of waterhyacinth with the applied temperatures ranged from 60, 70, 80, 90 and 100 °C.The stages of this research involve extraction, precipitation, washing and drying. The pectin produced was, then, identified by reacting it with water, ethanol 96 %, NaOH and spectrophotometer IR. Its product was, then, compared to the comparing pectin. To determine the methoxyl contents, the acid - base titration was used. The resulting data were analysed and tested using One Direction Anava with SPSS 10.0 program. From the quantitative used by this study, pectin was produced. This is shown by the gel-formation. The rendements produced with the extraction temperatures of 60, 70, 80, 90 and 100 °C were 0,428 %; 0,487 %; 0,629 %; 0,774 % and 0,958% respectively. While its methoxyl contents were 3,879 %; 3,993 %; 4,413 %; 3,573 % and 2,837 %. Based on the analysed data, it was found that the treatment with the extraction temperature gives a significant influence on the rendement and pectin methoxyl contents of waterhyacinth. Keywords: extraction, pectin, methoxyl contents

Potato tuber pectin structure is influenced by pectin methyl esterase activity and impacts on cooked potato texture

OpenAIRE

Ross, Heather A.; Wright, Kathryn M.; McDougall, Gordon J.; Roberts, Alison G.; Chapman, Sean N.; Morris, Wayne L.; Hancock, Robert D.; Stewart, Derek; Tucker, Gregory A.; James, Euan K.; Taylor, Mark A.

2010-01-01

Although cooked potato tuber texture is an important trait that influences consumer preference, a detailed understanding of tuber textural properties at the molecular level is lacking. Previous work has identified tuber pectin methyl esterase activity (PME) as a potential factor impacting on textural properties. In this study, tuber PME isoform and gene expression profiles have been determined in potato germplasm with differing textural properties as assessed using an amended wedge fracture m...

Effect of pectin edible coating enriched with essential oils of citrus on strawberry quality during refrigerated storage and shelf life

Directory of Open Access Journals (Sweden)

Soma Abdi

2017-06-01

Full Text Available Postharvest life of strawberry fruit is very short due to humidity and high metabolic activity. In order to extend the shelf life and quality of strawberry (cv. parous, effects of pectin coating enriched with different concentrations of lemon and orange peel essential oil were assessed at 20˚C for 6 days or 5˚C to 12 days. The experiment conducted based on a complete randomized design (CDR in 3 replications with 6 treatments including control (distilled water, pectin (1%, pectin enriched with orange peel essential oil (0.5 and 1% and pectin containing lemon peel essential oil (0.5 and 1%. Fruit quality was evaluated by marketing, weight loss, anthocyanin content, ascorbic acid content, total protein and chlorophyll of calyx every 3 days. Based on results coating fruits with citrus essential oil carried by pectin delayed the change in weight loss, total protein, anthocyanin content, maintained ascorbic acid content of fruits and also reduced chlorophyll destruction of calyx. The results showed that pectin coating containing lemon essential oil had a significant effect on the maintaining the visual quality of the fruit during the storage, delayed the weight loss and showed better results compared to the other coatings and to the control fruit. In addition, the maximum content of ascorbic acid and anthocyanin were obtained for strawberries coated with pectin containing lemon essential oil 1% after 12 days storage of fruits at 5˚C. All coatings significantly reduced weight loss of fresh strawberries during storage at 5˚C and 20˚C compared to the uncoated fruits. Results indicated that adding high concentrations (1% of orange peel essential oil into pectin coatings did not improve quality of fruits. In addition, it was found that adding orange peel essential oil to pectin coating accelerate decay of fruits. Based on results, pectin coating containing 1% lemon essential oil considered an appropriate treatment to improve shelf life and storage

Concentration of lemon pectin extract by ultrafiltration

Directory of Open Access Journals (Sweden)

Damián Stechina

2012-09-01

Full Text Available Current annual lemon production in Argentina is about 900 thousand t. 75% is used industrially to obtain pasteurized juice concentrate. Since 40 - 45 % of citrus fruit content is peel and seeds, the annual lemon residue yield is 360 thousand t. Lemon peel contains about 30% (B.S. of peptic substances with an important commercial value due to its gelling and thickening properties for food, chemical, pharmacological and cosmetic products. Membrane processes have many applications in food manufacture. The objective of this study is to analyze the influence of ultrafiltration operating variables on instant permeate flow (Fp and on the energy requirement for pectin extract concentration from lemon peel. A DDS lab module was used, lab 20-772 model with synthetic material membranes, 9 kDa, shear force, the intrinsic membrane resistance (Rm being 3*1013 m -1 . Results show that Fp decrease caused by polarization induced resistance occurrence and the influence of operating variables on Fp offer relevant data to estimate the energy requirement in relation to feeding flow at constant temperature, which may be compared to pectin concentration increase in the retained flow in relation to initial extract concentration.

Affecting osteoblastic responses with in vivo engineered potato pectin fragments

DEFF Research Database (Denmark)

Kokkonen, Hanna; Verhoef, Renè; Kauppinen, Kyösti

2012-01-01

Pectins, complex plant-derived polysaccharides, are novel candidates for biomaterial nanocoatings. Pectic rhamnogalacturonan-I regions (RG-I) can be enzymatically treated to so-called modified hairy regions (MHR). We surveyed the growth and differentiation of murine preosteoblastic MC3T3-E1 cells...... subtler. However, tetracycline-stained calcium-containing mineral was detected merely only on uncoated TCPS. These results indicate the possibility to affect bone cell growth with in vivo-modified pectin fragments, consecutively providing information on the significance of certain monosaccharides...... on the biocompatibility of these polysaccharides. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012....

Effect of Morphology and Size of Halloysite Nanotubes on Functional Pectin Bionanocomposites for Food Packaging Applications.

Science.gov (United States)

Makaremi, Maziyar; Pasbakhsh, Pooria; Cavallaro, Giuseppe; Lazzara, Giuseppe; Aw, Yoong Kit; Lee, Sui Mae; Milioto, Stefana

2017-05-24

Pectin bionanocomposite films filled with various concentrations of two different types of halloysite nanotubes were prepared and characterized in this study as potential films for food packaging applications. The two types of halloysite nanotubes were long and thin (patch) (200-30 000 nm length) and short and stubby (Matauri Bay) (50-3000 nm length) with different morphological, physical, and dispersibility properties. Both matrix (pectin) and reinforcer (halloysite nanotubes) used in this study are considered as biocompatible, natural, and low-cost materials. Various characterization tests including Fourier transform infrared spectroscopy, field emission scanning electron microscopy, release kinetics, contact angle, and dynamic mechanical analysis were performed to evaluate the performance of the pectin films. Exceptional thermal, tensile, and contact angle properties have been achieved for films reinforced by patch halloysite nanotubes due to the patchy and lengthy nature of these tubes, which form a bird nest structure in the pectin matrix. Matauri Bay halloysite nanotubes were dispersed uniformly and individually in the matrix in low and even high halloysite nanotube concentrations. Furthermore, salicylic acid as a biocidal agent was encapsulated in the halloysite nanotubes lumen to control its release kinetics. On this basis, halloysite nanotubes/salicylic acid hybrids were dispersed into the pectin matrix to develop functional biofilms with antimicrobial properties that can be extended over time. Results revealed that shorter nanotubes (Matauri Bay) had better ability for the encapsulation of salicylic acid into their lumen, while patchy structure and longer tubes of patch halloysite nanotubes made the encapsulation process more difficult, as they might need more time and energy to be fully loaded by salicylic acid. Moreover, antimicrobial activity of the films against four different strains of Gram-positive and Gram-negative bacteria indicated the

Mode of de-esterification of alkaline and acidic pectin methyl esterases at different pH conditions.

Science.gov (United States)

Duvetter, Thomas; Fraeye, Ilse; Sila, Daniel N; Verlent, Isabel; Smout, Chantal; Hendrickx, Marc; Van Loey, Ann

2006-10-04

Highly esterified citrus pectin was de-esterified at pH 4.5 and 8.0 by a fungal pectin methyl esterase (PME) that was shown to have an acidic isoelectric pH (pI) and an acidic pH optimum and by a plant PME that was characterized by an alkaline pI and an alkaline pH optimum. Interchain and intrachain de-esterification patterns were studied by digestion of the pectin products with endo-polygalacturonase and subsequent analysis using size exclusion and anion-exchange chromatography. No effect of pH was observed on the de-esterification mode of either of the two enzymes. Acidic, fungal PME converted pectin according to a multiple-chain mechanism, with a limited degree of multiple attack at the intrachain level, both at pH 4.5 and at pH 8.0. A multiple-attack mechanism, with a high degree of multiple attack, was more appropriate to describe the action mode of alkaline, plant PME, both at pH 4.5 and at pH 8.0.

Nano-encapsulation of olive leaf phenolic compounds through WPC-pectin complexes and evaluating their release rate.

Science.gov (United States)

Mohammadi, Adeleh; Jafari, Seid Mahdi; Assadpour, Elham; Faridi Esfanjani, Afshin

2016-01-01

In this study, W/O micro-emulsions as primary emulsions and a complex of whey protein concentrate (WPC) and pectin in the external aqueous phase were used to produce W/O/W emulsions. Average droplet size of primary W/O emulsion and multiple emulsions stabilized by WPC or WPC-pectin after one day of production was 6.16, 675.7 and 1443 nm, respectively, which achieved to 22.97, 347.7 and, 1992.4 nm after 20 days storage without any sedimentation. The encapsulation efficiency of phenolic compounds for stabilized W/O/W emulsions with WPC and WPC-pectin were 93.34% and 96.64%, respectively, which was decreased to 72.73% and 88.81% at 20th storage day. The lowest release of phenolics observed in multiple emulsions of WPC-pectin. These results suggest that nano-encapsulation of olive leaf extract within inner aqueous phase of W/O/W emulsions was successful, and there could be a high potential for the application of olive leaf extract in fortification of food products. Copyright © 2015 Elsevier B.V. All rights reserved.

Radiation syntheses of Pectin/acrylamide (PEC/PAM) and Pectin/Diethylaminoethylmethacrylate (PEC/DEAMA) hydrogels as drug delivery systems

International Nuclear Information System (INIS)

Abou El Fadl, F.I.; Maziad, N.A.

2015-01-01

Different pH responsive copolymer hydrogels based on pectin were prepared by the effect of radiation. The physical and chemical properties of prepared hydrogels were studied by FTIR, and TGA. Also, the prepared hydrogels were evaluated for the possible use as drug delivery system for chlortetracycline HCL as model drug. The results revealed that the swelling ratios and the release behavior of hydrogels depend mainly on the pH of the medium and the hydrogel composition. (author)

Partial demethylation of oligogalacturonides by pectin methyl esterase 1 is required for eliciting defence responses in wild strawberry (Fragaria vesca).

Science.gov (United States)

Osorio, Sonia; Castillejo, Cristina; Quesada, Miguel A; Medina-Escobar, Nieves; Brownsey, Geoff J; Suau, Rafael; Heredia, Antonio; Botella, Miguel A; Valpuesta, Victoriano

2008-04-01

In addition to the role of the cell wall as a physical barrier against pathogens, some of its constituents, such as pectin-derived oligogalacturonides (OGA), are essential components for elicitation of defence responses. To investigate how modifications of pectin alter defence responses, we expressed the fruit-specific Fragaria x ananassa pectin methyl esterase FaPE1 in the wild strawberry Fragaria vesca. Pectin from transgenic ripe fruits differed from the wild-type with regard to the degree and pattern of methyl esterification, as well as the average size of pectin polymers. Purified oligogalacturonides from the transgenic fruits showed a reduced degree of esterification compared to oligogalacturonides from wild-type fruits. This reduced esterification is necessary to elicit defence responses in strawberry. The transgenic F. vesca lines had constitutively activated pathogen defence responses, resulting in higher resistance to the necrotropic fungus Botrytis cinerea. Further studies in F. vesca and Nicotiana benthamiana leaves showed that the elicitation capacity of the oligogalacturonides is more specific than previously envisaged.

Time domain NMR and conductivity study of apple pectin biopolymers

International Nuclear Information System (INIS)

Mattos, Ritamara I.; Souto, Sergio; Tambelli, Caio E.

2015-01-01

This communication presents results of "1H nuclear magnetic resonance of continuous distributions of spin-spin relaxation time (T_2) and A.C. conductivity of apple pectin biopolymers plasticized with glycerol and containing acetic acid. The continuous distributions reveals up to three components of spin-spin relaxation times (T_2). The two short T_2 components were associated with protons of pectin polymer chain and the longer T_2 can be attributed with the protons of the glycerol. The conductivity values increase with glycerol concentration with maximum at 7.9 x 10"-"4 S cm"-"1 for sample with 3.0 g of glycerol at 83 deg C. The behavior of activation energy and T_2 continuous distribution indicate an increase of proton mobility due the structural changes caused by glycerol addition. (author)

Pectin Biosynthesis Is Critical for Cell Wall Integrity and Immunity in Arabidopsis thaliana.

Science.gov (United States)

Bethke, Gerit; Thao, Amanda; Xiong, Guangyan; Li, Baohua; Soltis, Nicole E; Hatsugai, Noriyuki; Hillmer, Rachel A; Katagiri, Fumiaki; Kliebenstein, Daniel J; Pauly, Markus; Glazebrook, Jane

2016-02-01

Plant cell walls are important barriers against microbial pathogens. Cell walls of Arabidopsis thaliana leaves contain three major types of polysaccharides: cellulose, various hemicelluloses, and pectins. UDP-D-galacturonic acid, the key building block of pectins, is produced from the precursor UDP-D-glucuronic acid by the action of glucuronate 4-epimerases (GAEs). Pseudomonas syringae pv maculicola ES4326 (Pma ES4326) repressed expression of GAE1 and GAE6 in Arabidopsis, and immunity to Pma ES4326 was compromised in gae6 and gae1 gae6 mutant plants. These plants had brittle leaves and cell walls of leaves had less galacturonic acid. Resistance to specific Botrytis cinerea isolates was also compromised in gae1 gae6 double mutant plants. Although oligogalacturonide (OG)-induced immune signaling was unaltered in gae1 gae6 mutant plants, immune signaling induced by a commercial pectinase, macerozyme, was reduced. Macerozyme treatment or infection with B. cinerea released less soluble uronic acid, likely reflecting fewer OGs, from gae1 gae6 cell walls than from wild-type Col-0. Although both OGs and macerozyme-induced immunity to B. cinerea in Col-0, only OGs also induced immunity in gae1 gae6. Pectin is thus an important contributor to plant immunity, and this is due at least in part to the induction of immune responses by soluble pectin, likely OGs, that are released during plant-pathogen interactions. © 2016 American Society of Plant Biologists. All rights reserved.

Distribution of pectins in the pollen apertures of Oenothera hookeri.velans ster/+ster.

Science.gov (United States)

Noher de Halac, I; Cismondi, I A; Rodriguez-Garcia, M I; Famá, G

2003-04-01

Cell wall pectins are some of the most complex biopolymers known, and yet their functions remain largely mysterious. The aim of this paper was to deepen the study of the spatial pattern of pectin distribution in the aperture of Oenothera hookeri.velans ster/+ster fertile pollen. We used "in situ" immunocytochemical techniques at electron microscopy, involving monoclonal antibodies JIM5 and JIM7 directed against pectin epitopes in fertile pollen grains of Oenothera hookeri.velans ster/+ster. The same region was also analyzed by classical cytochemistry for polysaccharide detection. Immunogold labelling at the JIM7 epitope showed only in mature pollen labelling mainly located at the intine endo-aperture region. Cytoplasmic structures near the plasma membrane of the vegetative cell showed no labelling gold grains. In the same pollen stge the labelling at the JIM5 epitope was mostly confined to a layer located in the limit between the endexine and the ektexine at the level of the border of the oncus. Some tubuli at the base of the ektexine showed also an accumulation of gold particles. No JIM5 label was demonstrated in the aperture chamber and either in any cytoplasmic structure of the pollen grains. The immunocytochemical technique, when compared with the traditional methods for non-cellulose polysaccharide cytochemistry is fare more sensitive and allows the univocal determination of temporal and spatial location of pectins recognized by the JIM7 and JIM5 MAbs.

Isolation of pectin from pumpkin (Cucurbita moschata, L.) by acid hydrolysis;Isolamento de pectina de abobora (Cucurbita moschata, L.) por hidrolise acida

Energy Technology Data Exchange (ETDEWEB)

Souza, Jose R.R.; Ricardo, Nagila M.P.S.; Paula, Regina C.M. de; Feitosa, Judith P.A., E-mail: judith@dqoi.ufc.b [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Quimica Organica e Inorganica. Lab. de Polimeros; Brito, Edy S. [EMBRAPA Agroindustria Tropical, Fortaleza, CE (Brazil)

2009-07-01

Pumpkin (Cucurbita moschata, L.) constitutes an excellent source of carotenoids, precursors of vitamin A. Besides, it also that constitutes also a great natural source of low-cost pectin. Pectin is a heterogeneous complex polysaccharide found in the primary cell wall of most plants and its effect on health is receiving increasing interest from the scientific community. In this work, high-methoxy pectin was obtained from pumpkin (Cucurbita moschata, L.) through the acid hydrolysis methodology. The pectin obtained was characterized by FTIR, NMR {sup 1}H, GPC and rheology. (author)

Activity of pectin methyl esterase during blanching of peaches

NARCIS (Netherlands)

Tijskens, L.M.M.; Rodis, P.S.; Hertog, M.L.A.T.M.; Proxenia, N.; Dijk, van C.

1999-01-01

The activity of pectin methyl esterase (PE) in peaches during blanching treatments was modelled and analyzed. It was postulated that the enzyme exists in two configurations, one bound and one soluble. The bound configuration can be converted into the soluble configuration. These two configurations

An acidic pectin lyase from Aspergillus niger with favourable efficiency in fruit juice clarification.

Science.gov (United States)

Xu, S X; Qin, X; Liu, B; Zhang, D Q; Zhang, W; Wu, K; Zhang, Y H

2015-02-01

The pectin lyase gene pnl-zj5a from Aspergillus niger ZJ5 was identified and expressed in Pichia pastoris. PNL-ZJ5A was purified by ultrafiltration, anion exchange and gel chromatography. The Km and Vmax values determined using citrus pectin were 0.66 mg ml(-1) and 32.6 μmol min(-1) mg(-1) , respectively. PNL-ZJ5A exhibited optimal activity at 43°C and retained activity over 25-50°C. PNL-ZJ5A was optimally active at pH 5 and effective in apple juice clarification. Compared with controls, PNL-ZJ5A increased the fruit juice yield significantly. Furthermore, PNL-ZJ5A reduced the viscosity of apple juice by 38.8% and increased its transmittance by 86.3%. PNL-ZJ5A combined with a commercial pectin esterase resulted in higher juice volume. © 2014 The Society for Applied Microbiology.

Intron retention regulates the expression of pectin methyl esterase inhibitor (Pmei) genes during wheat growth and development.

Science.gov (United States)

Rocchi, V; Janni, M; Bellincampi, D; Giardina, T; D'Ovidio, R

2012-03-01

Pectin is an important component of the plant cell wall and its remodelling occurs during normal plant growth or following stress responses. Pectin is secreted into the cell wall in a highly methyl-esterified form and subsequently de-methyl-esterified by pectin methyl esterase (PME), whose activity is controlled by the pectin methyl esterase inhibitor protein (PMEI). Cereal cell wall contains a low amount of pectin; nonetheless the level and pattern of pectin methyl esterification play a primary role during development or pathogen infection. Since few data are available on the role of PMEI in plant development and defence of cereal species, we isolated and characterised three Pmei genes (Tdpmei2.1, Tdpmei2.2 and Tdpmei3) and their encoded products in wheat. Sequence comparisons showed a low level of intra- and inter-specific sequence conservation of PMEIs. Tdpmei2.1 and Tdpmei2.2 share 94% identity at protein level, but only 20% identity with the product of Tdpmei3. All three Tdpmei genes code for functional inhibitors of plant PMEs and do not inhibit microbial PMEs or a plant invertase. RT-PCR analyses demonstrated, for the first time to our knowledge, that Pmei genes are regulated by intron retention. Processed and unprocessed transcripts of Tdpmei2.1 and Tdpmei2.2 accumulated in several organs, but anthers contained only mature transcripts. Tdpmei3 lacks introns and its transcript accumulated mainly in stem internodes. These findings suggest that products encoded by these Tdpmei genes control organ- or tissue-specific activity of specific PME isoforms in wheat. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

Synthesis and Characterization Pectin-Carboxymethyl Chitosan crosslinked PEGDE as biosorbent of Pb(II) ion

Science.gov (United States)

Hastuti, Budi; Siswanta, Dwi; Mudasir; Triyono

2018-01-01

Pectin and chitosan are biodegradable polymers, potentially applied as a heavy metal adsorbents. Unfortunately both biosorbents pectin and chitosan have a weakness in acidic media. For this purpose required modified pectin and chitosan. The modified adsorben is intended to obtain a stable adsorbent and resistance under acid. The research was done by experimental method in laboratory. The stages of this research are the synthesis of carboxymethyl chitosan (CMC), synthesis of Pec-CMC-PEGDE film adsorbent, stabily test under acid, the characterization of active group using FTIR, stability characterization of Pec-CMC-PEGDE powder adsorbent using XRD, termo stability using DTA-TGA. The results of the research have shown that: pectin and CMC can be cross-linked using PEGDE crosslinking agent, the film adsorbent was stable under HCl 1 M, the film adsorbent have active group comprise of carboxylate and amine groups. The result of characterization using XRD, shows that the adsorbent is semi-crystalline. Base on termo stability, the film adsorbent Pec-CMC-PEGDE stable up to 600°C. The film can be applied as an adsobent of Pb (II) ion remediation. The optimum pH of pec-CMC-PEGDE in adsorbed of Pb(II) was reached at pH 5 with 99.99% absorbent adsorbed and of and adsorption capacity was 46.11 mg/g.

Pectin Methylesterification Impacts the Relationship between Photosynthesis and Plant Growth1[OPEN

Science.gov (United States)

Kim, Sang-Jin; Renna, Luciana; Brandizzi, Federica

2016-01-01

Photosynthesis occurs in mesophyll cells of specialized organs such as leaves. The rigid cell wall encapsulating photosynthetic cells controls the expansion and distribution of cells within photosynthetic tissues. The relationship between photosynthesis and plant growth is affected by leaf area. However, the underlying genetic mechanisms affecting carbon partitioning to different aspects of leaf growth are not known. To fill this gap, we analyzed Arabidopsis plants with altered levels of pectin methylesterification, which is known to modulate cell wall plasticity and plant growth. Pectin methylesterification levels were varied through manipulation of cotton Golgi-related (CGR) 2 or 3 genes encoding two functionally redundant pectin methyltransferases. Increased levels of methylesterification in a line over-expressing CGR2 (CGR2OX) resulted in highly expanded leaves with enhanced intercellular air spaces; reduced methylesterification in a mutant lacking both CGR-genes 2 and 3 (cgr2/3) resulted in thin but dense leaf mesophyll that limited CO2 diffusion to chloroplasts. Leaf, root, and plant dry weight were enhanced in CGR2OX but decreased in cgr2/3. Differences in growth between wild type and the CGR-mutants can be explained by carbon partitioning but not by variations in area-based photosynthesis. Therefore, photosynthesis drives growth through alterations in carbon partitioning to new leaf area growth and leaf mass per unit leaf area; however, CGR-mediated pectin methylesterification acts as a primary factor in this relationship through modulation of the expansion and positioning of the cells in leaves, which in turn drive carbon partitioning by generating dynamic carbon demands in leaf area growth and leaf mass per unit leaf area. PMID:27208234

A Comprehensive Approach for Pectin Chemical and Functional Characterization

DEFF Research Database (Denmark)

de Sousa, António Felipe Gomes Teixeira

In this work, a comprehensive approach for the chemical and functional analysis of pectin was used in order to relate the different extraction conditions used to the polymer structure and the final functional (mainly gelling) properties. A wide range of methods were utilized including chemical an...

The effect of copper ions, aluminum ions and their mixtures on separation of pectin from the sugar beet juice

OpenAIRE

Kuljanin, Tatjana A.; Mišljenović, Nevena M.; Koprivica, Gordana B.; Jevrić, Lidija R.; Grbić, Jasna P.

2013-01-01

In sugar industry there is a problem of the presence of undesirable macromolecules compounds such as pectin in sugar beet juice. The affinity of calcium ions commonly used in the sugar industry for the removal of pectin from the sugar beet juice is relatively small. Coagulation and precipitation of pectin can be performed by process of discharging that is chemically induced. Compounds with di- and trivalent cations such as pure CuSO4, Al2(SO4)3 or their mixtures can be applied for clari...

Effect of pectin and hemicellulose removal from hemp fibres on the mechanical properties of unidirectional hemp/epoxy composites

DEFF Research Database (Denmark)

Liu, Ming; Meyer, Anne S.; Fernando, Dinesh

2016-01-01

The objective of this study was to investigate the effect of pectin and hemicellulose removal from hemp fibres on the mechanical properties of hemp fibre/epoxy composites. Pectin removal by EDTA and endo-polygalacturonase (EPG) removed epidermal and parenchyma cells from hemp fibres and improved...

Optimization of enzymatic extraction of pectin from Opuntia ficus indica cladodes after mucilage removal.

Science.gov (United States)

Bayar, Nadia; Friji, Marwa; Kammoun, Radhouane

2018-02-15

In this study, pectin was isolated from Opuntia ficus indica (OFI) cladodes after removing mucilage using the xylanase and cellulase. The process variables were optimized by the Box Behnken design with three factors at three levels. The optimal extraction condition obtained was: liquid to solid (LS), cellulase to xylanase and enzymes to matter ratios of 22ml/g, 2:1U/U and 4U/g, respectively. The simulated extraction yield of 17.91% was validated by the experimental result (16.67±0.30). The enzyme-extracted pectin from OFI cladodes (EAEPC) was low methylated, with a high uronic acid content, a water and oil holding capacity of 5.42g/g and 1.23g/g, respectively, a good foam and emulsion stability and important DPPH radical scavenging activity. Both the OFI cladodes and enzymatic process present promising alternatives to traditional sources and extraction processes of pectin, respectively. EAEPC thus represents a promising additive in food industries. Copyright © 2017. Published by Elsevier Ltd.

Soluble Fermentable Dietary Fibre (Pectin) Decreases Caloric Intake, Adiposity and Lipidaemia in High-Fat Diet-Induced Obese Rats

Science.gov (United States)

Adam, Clare L.; Thomson, Lynn M.; Williams, Patricia A.; Ross, Alexander W.

2015-01-01

Consumption of a high fat diet promotes obesity and poor metabolic health, both of which may be improved by decreasing caloric intake. Satiety-inducing ingredients such as dietary fibre may be beneficial and this study investigates in diet-induced obese (DIO) rats the effects of high or low fat diet with or without soluble fermentable fibre (pectin). In two independently replicated experiments, young adult male DIO rats that had been reared on high fat diet (HF; 45% energy from fat) were given HF, low fat diet (LF; 10% energy from fat), HF with 10% w/w pectin (HF+P), or LF with 10% w/w pectin (LF+P) ad libitum for 4 weeks (n = 8/group/experiment). Food intake, body weight, body composition (by magnetic resonance imaging), plasma hormones, and plasma and liver lipid concentrations were measured. Caloric intake and body weight gain were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Body fat mass increased in HF, was maintained in LF, but decreased significantly in LF+P and HF+P groups. Final plasma leptin, insulin, total cholesterol and triglycerides were lower, and plasma satiety hormone PYY concentrations were higher, in LF+P and HF+P than in LF and HF groups, respectively. Total fat and triglyceride concentrations in liver were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Therefore, the inclusion of soluble fibre in a high fat (or low fat) diet promoted increased satiety and decreased caloric intake, weight gain, adiposity, lipidaemia, leptinaemia and insulinaemia. These data support the potential of fermentable dietary fibre for weight loss and improving metabolic health in obesity. PMID:26447990

Effects of Ca, Cu, Al and La on pectin gel strength: implications for plant cell walls.

Science.gov (United States)

McKenna, Brigid A; Nicholson, Timothy M; Wehr, J Bernhard; Menzies, Neal W

2010-06-16

Rheology of Ca-pectate gels is widely studied, but the behaviour of pectate gels formed by Cu, Al and La is largely unknown. It is well known that gel strength increases with increasing Ca concentration, and it is hypothesised that this would also be the case for other cations. Pectins are a critical component of plant cell walls, imparting various physicochemical properties. Furthermore, the mechanism of metal toxicity in plants is hypothesised to be, in the short term, related to metal interactions with cell wall pectin. This study investigated the influence of Ca, Cu, Al and La ion concentrations at pH 4 on the storage modulus as a function of frequency for metal-pectin gels prepared from pectin (1%) with a degree of esterification of 30%. Gels were formed in situ over 6d in metal chloride solution adjusted daily to pH 4. Cation concentration was varied to develop a relationship between gel strength and cation concentration. At similar levels of cation saturation, gel strength increased in the order of LaCu. The swelling of the gels also varied between cations with Ca gels being the most swollen. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Restricted cell elongation in Arabidopsis hypocotyls is associated with a reduced average pectin esterification level

OpenAIRE

Derbyshire, Paul; McCann, Maureen C; Roberts, Keith

2007-01-01

Abstract Background Cell elongation is mainly limited by the extensibility of the cell wall. Dicotyledonous primary (growing) cell walls contain cellulose, xyloglucan, pectin and proteins, but little is known about how each polymer class contributes to the cell wall mechanical properties that control extensibility. Results We present evidence that the degree of pectin methyl-esterification (DE%) limits cell growth, and that a minimum level of about 60% DE is required for normal cell elongatio...

Characterization of chars form biomass-derived materials: pectin chars

Energy Technology Data Exchange (ETDEWEB)

Sharma, R.K.; Wooten, J.B.; Baliga, V.L.; Hajaligol, M.R. [Philip Morris USA, Richmond, VA (United States). Research Center

2001-10-09

The effect of pyrolysis conditions on the yield and composition of char from pectin was studied. The volatile product was analyzed by gas chromatography/mass spectrometry (GC/MS). The solid product, i.e. char, was characterised by solid-state {sup 13}C nuclear magnetic resonance (NMR) and Fourier-transform infrared (FTIR) spectrsocopy. The char was also analysed for its elemental composition and surface area. The surface morphology of the char was studied by scanning electron microscopy (SEM). The results were compared to those from chlorogenic acid (CA). For both pectin and CA, the char yield decreased with increasing temperature before levelling-off at ca.20% of the starting substrate in non-oxidative runs. In oxidative runs, the char yields from both substrates became negligible at 550{degree}C. NMR analysis indicated that the aromatic character of char increased as the pyrolysis temperature increased. The oxygen functionality was progressively lost and the resonance bands corresponding to carbonyl groups mostly disappeared above 350{degree}C. FTIR analysis also suggested the loss of hydroxyl and carbonyl groups from chars at high temperatures. The H/C and O/C ratios of chars decreased continuously with increasing temperature. The oxidative chars showed characteristics essentially similar to those of the non-oxidative chars. The surface area of char was negligible at low temperatures, but increased dramatically to a maximum of 70 m{sup 2}g{sup -1} at 450{degree}C before decreasing at 500{degree}C. SEM analysis indicated that the pyrolysis of pectin occurred via softening and melting of the substrate followed by bubble formation. At high temperatures, surface etching followed by the appearance of crystal

Effects of microwave power and irradiation time on pectin extraction from watermelon rinds (Citrullus lanatus) with acetic acid using microwave assisted extraction method

Science.gov (United States)

Sari, A. M.; Ishartani, D.; Dewanty, P. S.

2018-01-01

The aims of this research are to study the effect of microwave power (119.7 W, 199.5 W and 279.3 W) and irradiation time (6, 9 and 12 min) on pectin extraction by using Microwave Assisted Extraction (MAE) with acetic acid and to do a preliminary characterization of pectin from watermelon rinds. A randomized factorial design with two factors was used to determine the effect of microwave power and processing time on the yield, equivalent weight, degree of methoxylation (DM), galacturonic acid content (GA) and the degree of esterification (DE) of extracted pectin. The results showed that extracted pectin from watermelon rinds using MAE method have yield ranged from 3.925% to 5.766%, with equivalent weight ranged from 1249.702 to 2007.756. Extracted pectin have a DM value ranged from 3.89% to 10.81%. Galacturonic acid content that meets with IPPA standard resulted from extraction condition of 279.3-watt microwave power for 9 min and 12 min. The degree of esterification (DE) value ranged from 56.86% to 85.76%, and this value exhibited a relatively high methoxyl pectin (>50%). The best pectin properties was obtained at a microwave power of 279.3 watts for 12 min.

Contribution of the pectin in the cesium elimination in organism. results of analysis on Belarus children

International Nuclear Information System (INIS)

2007-01-01

The results make appear that the cesium 137 would be eliminated less quick than what the ICRP considered for its models. Pectin would accelerate the cesium elimination but less quick than what is announced by its promotors. Politically speaking, the pectin is ignored by the officials of medicine and radiation protection at the pretext that its efficiency is not proved but no study is made. (N.C.)

Physico-chemical and viscoelastic properties of high pressure homogenized lemon peel fiber fraction suspensions obtained after sequential pectin extraction

NARCIS (Netherlands)

Willemsen, K.L.D.D.; Panozzo, A.; Moelants, K.; Debon, S.J.J.; Desmet, C.; Cardinaels, R.M.; Moldenaers, P.; Wallecan, J.; Hendrickx, M.E.G.

2017-01-01

The viscoelastic properties of high pressure homogenized lemon peel cell wall fiber suspensions, obtained after sequential selective pectin extraction, were investigated in the current study. For comparison, a general pectin extraction was additionally performed on lemon peel under acid thermal

Changes in pectins and product consistency during the concentration of tomato juice to paste.

Science.gov (United States)

Anthon, Gordon E; Diaz, Jerome V; Barrett, Diane M

2008-08-27

Concentrating tomato juice to paste during the tomato season allows for preservation and long-term storage, but subsequent dilution for formulation of value-added products is known to result in a loss of consistency. To understand the reasons for this, samples of unconcentrated juice, processing intermediates, and concentrated paste were collected from an industrial processing plant during normal commercial production. All samples were diluted with water to 5 degrees Brix and then analyzed for consistency and pectin content. Whole juice consistency, measured with a Bostwick consistometer, decreased through the course of juice concentration, with the largest change occurring early in the process, as the juice was concentrated from 5 to 10 degrees Brix. This decrease in consistency occurred during the production of paste from both hot- and cold-break juices. The change in Bostwick value was correlated with a decrease in the precipitate weight ratio. The loss of consistency during commercial processing was not the direct result of water removal because a sample of this same 5 degrees Brix juice could be concentrated 2-fold in a vacuum oven and then diluted back to 5 degrees Brix with no change in consistency or precipitate ratio. Total pectin content did not change as the juice was concentrated to paste, but the proportion of the total pectin that was water soluble increased. The greatest increases in pectin solubility occurred during the hot break and late in the process where the evaporator temperature was the highest.

High-throughput screening of Erwinia chrysanthemi pectin methylesterase variants using carbohydrate microarrays

DEFF Research Database (Denmark)

Øbro, Jens; Sørensen, Iben; Derkx, Patrick

2009-01-01

the activity of a series of variant enzymes based on the PME from the important pathogen Erwinia chrysanthemi. A library of 99 E. chrysanthemi PME mutants was created in which seven amino acids were altered by various different substitutions. Each mutant PME was incubated with a highly methyl esterified lime...

Effect of chitosan nanoparticles and pectin content on mechanical properties and water vapor permeability of banana puree films.

Science.gov (United States)

Martelli, Milena R; Barros, Taís T; de Moura, Márcia R; Mattoso, Luiz H C; Assis, Odilio B G

2013-01-01

Puree prepared from over-ripe peeled bananas was used as raw material for films processing in a laboratory padder. Pectin and glycerol as plasticizer were added in small concentrations and chitosan nanoparticles (88.79 ± 0.42 nm medium size) incorporated at 0.2% (dry weight basis) as reinforcement material. The mechanical properties, water vapor transmission, thermal stability, and scanning electron microscopy of fractured film surfaces were characterized. Both pectin and glycerol demonstrated an important role in promoting elongation and film handability as was expected. The incorporation of nanoparticles promoted noticeable improvement of the mechanical properties and acted in reducing the water vapor permeation rate, by 21% for films processed with pectin and up to 38% for films processed without pectin, when compared to the control (puree films with no pectin and nanoparticles additions). Microscopic observation revealed a denser matrix when nanoparticles are incorporated into the films. The development of films from fruit purees head to a new strategy for plastic processing from natural resources. The over-ripe or even waste banana can be adequately prepared for batch films processed with reasonable mechanical and barrier properties, suitable for applications in the food segment. The addition of small fractions of chitosan nanoparticles, form nanocomposites enhancing mechanical and thermal stability broadening potential film applications. © 2012 Institute of Food Technologists®

Water Susceptibility and Mechanical Properties of Thermoplastic Starch–Pectin Blends Reactively Extruded with Edible Citric Acid

OpenAIRE

Da Róz,Alessandra Luzia; Veiga-Santos,Pricila; Ferreira,Adriane Medeiros; Antunes,Thaís Cristina Ribeiro; Leite,Fabio de Lima; Yamaji,Fabio Minoru; Carvalho,Antonio José Felix de

2016-01-01

Pectin and starch are edible, non-toxic, biodegradable and obtained from renewable sources. Also, have the benefit to be easily cross-linked producing hydrogels. Reactive extrusion with edible citric acid and cross linking interactions was evaluated on extruded thermoplastic in natura and cationic starch-pectin blends. Materials water susceptibility and mechanical properties were characterised. Reactive extrusion decreased (up to 75% in natura starch) mechanical properties. Also have decrease...

Effects of pectin on fermentation characteristics, carbohydrate utilization, and microbial community composition in the gastrointestinal tract of weaning pigs

NARCIS (Netherlands)

Tian, Lingmin; Bruggeman, Geert; van den Berg, Marco; Borewicz, Klaudyna; Scheurink, Anton J. W.; Bruininx, Erik; de Vos, Paul; Smidt, Hauke; Schols, Henk A.; Gruppen, Harry

Scope: We aimed to investigate the effects of three different soluble pectins on the digestion of other consumed carbohydrates, and the consequent alterations of microbiota composition and SCFA levels in the intestine of pigs. Methods and results: Piglets were fed a low-methyl esterified pectin

Modification of Pectin and Hemicellulose Polysaccharides in Relation to Aril Breakdown of Harvested Longan Fruit

Science.gov (United States)

Wang, Duoduo; Zhang, Haiyan; Wu, Fuwang; Li, Taotao; Liang, Yuxiang; Duan, Xuewu

2013-01-01

To investigate the modification of cell wall polysaccharides in relation to aril breakdown in harvested longan fruit, three pectin fractions (WSP, water soluble pectin; CSP, CDTA-soluble pectin; ASP, alkali soluble pectin) and one hemicellulose fraction (4 M KOH-SHC, 4 M KOH-soluble hemicellulose) were extracted, and their contents, monosaccharide compositions and molecular weights were evaluated. As aril breakdown intensified, CSP content increased while ASP and 4 M KOH-SHC contents decreased, suggesting the solubilization and conversion of cell wall components. Furthermore, the molar percentage of arabinose (Ara), as the main component of the side-chains, decreased largely in CSP and ASP while that of rhamnose (Rha), as branch point for the attachment of neutral sugar side chains, increased during aril breakdown. Analysis of (Ara + Gal)/Rha ratio showed that the depolymerization of CSP and ASP happened predominantly in side-chains formed of Ara residues. For 4 M KOH-SHC, more backbones were depolymerized during aril breakdown. Moreover, it was found that the molecular weights of CSP, ASP and 4 M KOH-SHC polysaccharides tended to decrease as aril breakdown intensified. These results suggest that both enhanced depolymerization and structural modifications of polysaccharides in the CSP, ASP and 4 M KOH-SHC fractions might be responsible for aril breakdown of harvested longan fruit. PMID:24287911

Enhancement in in vitro anti-angiogenesis activity and cytotoxicity in lung cancer cell by pectin-PVP based curcumin particulates.

Science.gov (United States)

Gaikwad, Dinanath; Shewale, Rajnita; Patil, Vinit; Mali, Dipak; Gaikwad, Uday; Jadhav, Namdeo

2017-11-01

The aim of this work was to prepare pectin-poly (vinyl pyrrolidone) [PVP] based curcumin particulates to enhance the anticancer potential of curcumin, solubility and allow its localized controlled release. Pectin-PVP based curcumin particulates (PECTIN-PVP CUR) were prepared by spray drying technique in different ratios and were evaluated for surface morphology, micromeritics, flowability, particle size, drug content, in vitro dissolution, inhalable fraction, anti-angiogenesis/angiolysis and cytotoxicity. Results of micromeritic properties, Carr's index, Hausner's ratio and angle of repose were satisfactory. The batch CP3 was considered as optimum, due to excellent flowability, acceptable aggregation and enhanced solubility. The particle size and size distribution data of selected batch CP3 showed 90% of curcumin particulates having size less than 2.74μm, which may deposit to lungs. Twin Impinger studies showed that 29% of respirable fraction was generated, which could be directly delivered to lungs. The in vitro dissolution data showed many fold increase in dissolution rate. Angiolytic activity and MTT assay of PECTIN-PVP CUR have demonstrated enhancement in the anti-tumor potential, compared to curcumin alone. Altogether, PECTIN-PVP CUR were found suitable for local delivery and enhance its anticancer potential of curcumin. Copyright © 2017 Elsevier B.V. All rights reserved.

The influence of tannin, pectin and polyethylene glycol on attachment of {sup 15}N-labelled rumen microorganisms to cellulose

Energy Technology Data Exchange (ETDEWEB)

Bento, M.H.L. [Avian Science Research Centre, Animal Health Group, SAC, Edinburgh, Scotland (United Kingdom) and FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna (Austria)]. E-mail: helena.bento@sac.ac.uk; Acamovic, T. [Avian Science Research Centre, Animal Health Group, SAC, Edinburgh, Scotland (United Kingdom); Makkar, H.P.S. [FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna (Austria)

2005-08-19

The microbial attachment to and gas production from {alpha}-cellulose (Sigma; C-8002) without and with mimosa tannin (MT), pectin (P), polyethylene glycol (PEG), MT + P or MT + PEG, were investigated using the in vitro gas production system. Microbial attachment based on {sup 15}N-labelled rumen microorganisms in the residual pellet after 24 h incubation was estimated, which varied from 113.7 to 161.3 {mu}g {sup 15}N per g residual pellet. C + MT had the lowest microbial attachment (P < 0.05) of all treatments and C + P the highest (P < 0.05). Both pectin and PEG improved microbial attachment when added to C + MT (P < 0.001). Gas production was measured at 2, 4, 6, and 24 h. Mimosa tannin drastically reduced gas production only at 24 h (P < 0.001). Pectin increased gas production throughout the incubation period (P < 0.001). Both pectin and PEG increased gas production at 24 h, when added to C + MT (P < 0.05), however, for C + MT + P, the gas production was only half (P < 0.05) of the gas produced in the control (when only C incubated). A rapid degradation of pectin early in the incubation could have reduced the interaction of pectin with the MT. Microbial attachment agreed well with gas production at 24 h (R{sup 2} = 0.84, P < 0.001). However, the inclusion of MT and pectin may have resulted in differences in microbial profiles, thereby altering the capability of the adhered microbes to degrade cellulose. This assertion is supported by the lower gas production (ml per {mu}g of {sup 15}N) in the residual pellet measured for C + MT (0.054) and C + MT + P (0.159), compared with the other treatments (0.32 for C; 0.34 for C + P; 0.33 for C + PEG; and 0.33 for C + MT + PEG). A MT concentration of 194 g/kg diet reduced microbial attachment and activity of rumen microorganisms in vitro. Polyethylene glycol counteracted the effect of MT on microbial attachment and activity. Pectin exerted a beneficial effect on attachment and fermentation in the initial hours of incubation

Effect of extraction condition on properties of pectin from banana peels and its function as fat replacer in salad cream.

Science.gov (United States)

Maneerat, Nitjaree; Tangsuphoom, Nattapol; Nitithamyong, Anadi

2017-02-01

Banana peels are wasted from banana processing industry. Pectin is a soluble dietary fibre usually prepared from fruit and vegetable processing wastes. Pectin extraction from banana peels thus should be an effective way of waste utilization. This study aimed to determine the effect of extraction condition on the properties of pectin from peels of Nam Wa banana ( Musa (ABB group) 'Kluai Nam Wa') and its role as fat replacer in salad cream. Banana peel pectin (BPP) was extracted with HCl (pH 1.5) and water (pH 6.0) for 30-120 min at 90 ± 5 °C. Acid extraction yielded 7-11% pectin on a dry basis with galacturonic acid content (GalA), degree of methylation (DM), and viscosity-average molecular weight (M v ) of 42-47, 57-61%, and 17-40 kDa, respectively; while water-extracted BPP contained lower DM but higher GalA and M v . Prolonged extraction raised the pectin yield but lowered the M v of BPP and the viscosity of their solutions. Incorporation of BPP obtained from 60 min acid- and water-extraction into salad cream at 30% oil substitution level resulted in the decreases in viscosity and lightness. All reduced-fat samples were stable to cream separation during 3-weeks storage although the formula containing water-extracted BPP had larger oil droplet size and greater extent of droplet flocculation. There was no difference in sensory scores rated by 50 panelists on thickness, smoothness, and overall acceptability of the full- and reduced-fat salad creams. Therefore, Nam Wa banana peels can be an alternative source of pectin with potential application as fat replacer in food products.

Identification of Pectin Degrading Enzymes Secreted by Xanthomonas oryzae pv. oryzae and Determination of Their Role in Virulence on Rice.

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Lavanya Tayi

Full Text Available Xanthomonas oryzae pv.oryzae (Xoo causes the serious bacterial blight disease of rice. Xoo secretes a repertoire of plant cell wall degrading enzymes (CWDEs like cellulases, xylanases, esterases etc., which act on various components of the rice cell wall. The major cellulases and xylanases secreted by Xoo have been identified and their role in virulence has been determined. In this study, we have identified some of the pectin degrading enzymes of Xoo and assessed their role in virulence. Bioinformatics analysis indicated the presence of four pectin homogalacturonan (HG degrading genes in the genome of Xoo. The four HG degrading genes include one polygalacturonase (pglA, one pectin methyl esterase (pmt and two pectate lyases (pel and pelL. There was no difference in the expression of pglA, pmt and pel genes by laboratory wild type Xoo strain (BXO43 grown in either nutrient rich PS medium or in plant mimic XOM2 medium whereas the expression of pelL gene was induced in XOM2 medium as indicated by qRT-PCR experiments. Gene disruption mutations were generated in each of these four genes. The polygalacturonase mutant pglA- was completely deficient in degrading the substrate Na-polygalacturonicacid (PGA. Strains carrying mutations in the pmt, pel and pelL genes were as efficient as wild type Xoo (BXO43 in cleaving PGA. These observations clearly indicate that PglA is the major pectin degrading enzyme produced by Xoo. The pectin methyl esterase, Pmt, is the pectin de-esterifying enzyme secreted by Xoo as evident from the enzymatic activity assay performed using pectin as the substrate. Mutations in the pglA, pmt, pel and pelL genes have minimal effects on virulence. This suggests that, as compared to cellulases and xylanases, the HG degrading enzymes may not have a major role in the pathogenicity of Xoo.

Comparison of methods of zeta potential and residual turbidity of pectin solutions using calcium sulphate/aluminium sulphate as a precipitant

Directory of Open Access Journals (Sweden)

Kuljanin Tatjana A.

2017-01-01

Full Text Available The affinity of calcium ion binding from CaO used in the most common process of purification of sugar beet juice is relatively low. Therefore, large amounts of this compound are required. This paper presents the theoretical basis of a novel sugar beet juice purification method based on the application of the binary system CaSO4/Al2(SO4 . In order to monitor the process of coagulation and precipitation of pectin in the presence of CaSO4/Al2(SO43, two methods were compared: measurement of the zeta potential and of residual solution turbidity. The zeta potential of pectin solution was determined by electrophoretic method, while the residual turbidity was determined by spectrophotometry. Two model solutions of pectin (0.1 % w/w were investigated. Studies were performed with 10 different concentrations of the binary solution CaSO4/Al2(SO43 (50 - 500 g dm-3. The amount of the precipitant CaSO4/Al2(SO43 (1:1 w/w needed to achieve the minimum solution turbidity and charge neutralization of pectin particles (zero zeta potential were measured and compared. Colloidal destabilization occurred before a complete neutralization of the surface charge of pectin particles (zeta potential ~ 0 mV. Optimal quantities (490 - 705 mg g-1 pectin of the applied binary mixture, were obtained using both methods. This is much lower than the amount of CaO that is commonly used in the conventional process of sugar beet juice purification (about 9 g• g-1 pectin. The use of these precipitants could be important from both economic and environmental point of view. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR 31055

Identification of Pectin Degrading Enzymes Secreted by Xanthomonas oryzae pv. oryzae and Determination of Their Role in Virulence on Rice.

Science.gov (United States)

Tayi, Lavanya; Maku, Roshan V; Patel, Hitendra Kumar; Sonti, Ramesh V

2016-01-01

Xanthomonas oryzae pv.oryzae (Xoo) causes the serious bacterial blight disease of rice. Xoo secretes a repertoire of plant cell wall degrading enzymes (CWDEs) like cellulases, xylanases, esterases etc., which act on various components of the rice cell wall. The major cellulases and xylanases secreted by Xoo have been identified and their role in virulence has been determined. In this study, we have identified some of the pectin degrading enzymes of Xoo and assessed their role in virulence. Bioinformatics analysis indicated the presence of four pectin homogalacturonan (HG) degrading genes in the genome of Xoo. The four HG degrading genes include one polygalacturonase (pglA), one pectin methyl esterase (pmt) and two pectate lyases (pel and pelL). There was no difference in the expression of pglA, pmt and pel genes by laboratory wild type Xoo strain (BXO43) grown in either nutrient rich PS medium or in plant mimic XOM2 medium whereas the expression of pelL gene was induced in XOM2 medium as indicated by qRT-PCR experiments. Gene disruption mutations were generated in each of these four genes. The polygalacturonase mutant pglA- was completely deficient in degrading the substrate Na-polygalacturonicacid (PGA). Strains carrying mutations in the pmt, pel and pelL genes were as efficient as wild type Xoo (BXO43) in cleaving PGA. These observations clearly indicate that PglA is the major pectin degrading enzyme produced by Xoo. The pectin methyl esterase, Pmt, is the pectin de-esterifying enzyme secreted by Xoo as evident from the enzymatic activity assay performed using pectin as the substrate. Mutations in the pglA, pmt, pel and pelL genes have minimal effects on virulence. This suggests that, as compared to cellulases and xylanases, the HG degrading enzymes may not have a major role in the pathogenicity of Xoo.

Affecting osteoblastic responses with in vivo engineered potato pectin fragments

NARCIS (Netherlands)

Kokkonen, H.; Verhoef, R.P.; Kauppinen, K.; Muhonen, V.; Jorgensen, B.; Damager, I.; Schols, H.A.; Morra, M.; Ulvskov, P.; Tuukkanen, J.

2012-01-01

Pectins, complex plant-derived polysaccharides, are novel candidates for biomaterial nanocoatings. Pectic rhamnogalacturonan-I regions (RG-I) can be enzymatically treated to so-called modified hairy regions (MHR). We surveyed the growth and differentiation of murine preosteoblastic MC3T3-E1 cells on

Wax-incorporated emulsion gel beads of calcium pectinate for intragastric floating drug delivery.

Science.gov (United States)

Sriamornsak, Pornsak; Asavapichayont, Panida; Nunthanid, Jurairat; Luangtana-Anan, Manee; Limmatvapirat, Sontaya; Piriyaprasarth, Suchada

2008-01-01

The purpose of this study was to prepare wax-incorporated pectin-based emulsion gel beads using a modified emulsion-gelation method. The waxes in pectin-olive oil mixtures containing a model drug, metronidazole, were hot-melted, homogenized and then extruded into calcium chloride solution. The beads formed were separated, washed with distilled water and dried for 12 h. The influence of various types and amounts of wax on floating and drug release behavior of emulsion gel beads of calcium pectinate was investigated. The drug-loaded gel beads were found to float on simulated gastric fluid if the sufficient amount of oil was used. Incorporation of wax into the emulsion gel beads affected the drug release. Water-soluble wax (i.e. polyethylene glycol) increased the drug release while other water-insoluble waxes (i.e. glyceryl monostearate, stearyl alcohol, carnauba wax, spermaceti wax and white wax) significantly retarded the drug release. Different waxes had a slight effect on the drug release. However, the increased amount of incorporated wax in the formulations significantly sustained the drug release while the beads remained floating. The results suggest that wax-incorporated emulsion gel beads could be used as a carrier for intragastric floating drug delivery.

Oregano (Lippia graveolens) essential oil added within pectin edible coatings prevents fungal decay and increases the antioxidant capacity of treated tomatoes.

Science.gov (United States)

Rodriguez-Garcia, Isela; Cruz-Valenzuela, M Reynaldo; Silva-Espinoza, Brenda A; Gonzalez-Aguilar, Gustavo A; Moctezuma, Edgar; Gutierrez-Pacheco, M Melissa; Tapia-Rodriguez, Melvin R; Ortega-Ramirez, Luis A; Ayala-Zavala, J Fernando

2016-08-01

Tomato is a fruit widely consumed due to its flavor and nutritional value; however, it is susceptible to fungi contamination. Oregano essential oil (OEO) is a fungicide whose constituents are volatile; therefore, their incorporation within edible coatings can protect them and maintain their efficacy. In this context, this study evaluated the effect of OEO applied within pectin coatings on the inhibition of Alternaria alternata growth, antioxidant content and sensorial acceptability of tomatoes. The major volatile compounds of OEO were carvacrol (47.41%), p-cymene (26.44%) and thymol (3.02%). All the applied OEO concentrations (15.7, 25.9 and 36.1 g L(-1) ) inhibited the in vitro growth of A. alternata, whereas the in vivo effective concentrations were 25.9 and 36.1 g L(-1) . Additionally, there was an increment of total phenols and antioxidant activity in coated tomatoes compared to controls. Aroma acceptability of tomatoes was not affected by the pectin-OEO coating; additionally, the pectin, pectin-OEO 15.7 g L(-1) treatments and control tomatoes showed higher flavor acceptability than those coated with pectin-OEO 25.9 and 36.1 g L(-1) . Pectin-OEO coatings showed antifungal effect and increased the antioxidant activity without negative effects on the sensorial acceptability of tomatoes. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

A BIDISPERSE MODEL TO STUDY THE HYDROLYSIS OF MALTOSE USING GLUCOAMYLASE IMMOBILIZED IN SILICA AND WRAPPED IN PECTIN GEL

Directory of Open Access Journals (Sweden)

L.R.B. Gonçalves

1997-12-01

Full Text Available In this work, a bidisperse model is built to represent the hydrolysis of maltose using immobilized glucoamylase. The experimental set is a mixed-batch reactor, maintained at 30ºC, with pectin gel spherical particles that contain enzyme immobilized in macroporous silica. The possibility of substrate adsorption on the pectin gel is also studied because this phenomenon may result in smaller values of diffusivity. Equilibrium assays are then performed for different substrates (maltose, lactose and glucose at different temperatures and pHs. These assays show that adsorption on the pectin gel is not important for the three dextrins analysed. The bidisperse model presents a good fit with the experimental data, when using previously-estimated kinetic and mass transfer parameters (Gonçalves et al., 1997. This result shows that the methodology used (wrapping the silica in pectin gel is appropriate for experimental studies with silica, since it allows a higher degree of agitation without causing shearing

Cell Growth Inhibition Effect of DsiRNA Vectorised by Pectin-Coated Chitosan-Graphene Oxide Nanocomposites as Potential Therapy for Colon Cancer

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Haliza Katas

2017-01-01

Full Text Available Colonic-targeted drug delivery system is widely explored to combat colon-related diseases such as colon cancer. Dicer-substrate small interfering RNA (DsiRNA has been explored for cancer therapy due to its potency in targeting specific gene of interest. However, its application is limited by rapid degradation and poor cellular uptake. To address this, chitosan-graphene oxide (CS-GO nanocomposite was used to deliver DsiRNA effectively into cells. Additionally, pectin was used as compatibilization agent to allow specific delivery to the colon and protect the nanocomposites from the harsh environment in the stomach and small intestine. CS-GO-DsiRNA nanocomposites were prepared by electrostatic interaction between CS and GO prior to coating with pectin. The mean particle size of CS-GO-DsiRNA-pectin nanocomposites was 554.5±124.6 nm with PDI and zeta potential of 0.47±0.19 and −10.7±3.0 mV, respectively. TEM analysis revealed smooth and spherical shape of CS-GO-DsiRNA nanocomposites and the shape became irregular after pectin coating. FTIR analysis further confirmed the successful formation of CS-GO-DsiRNA-pectin nanocomposites. Furthermore, the nanocomposites were able to entrap high amount of DsiRNA (% entrapment efficiency of 92.6±3.9% with strong binding efficiency. CS-GO-DsiRNA-pectin nanocomposites also selectively inhibited cell growth of colon cancer cell line (Caco-2 cells and were able to decrease VEGF level significantly. In a nutshell, pectin-coated DsiRNA-loaded CS-GO nanocomposites were successfully developed and they have a great potential to deliver DsiRNA to the colon effectively.

Effects of Dietary Fibre (Pectin) and/or Increased Protein (Casein or Pea) on Satiety, Body Weight, Adiposity and Caecal Fermentation in High Fat Diet-Induced Obese Rats.

Science.gov (United States)

Adam, Clare L; Gratz, Silvia W; Peinado, Diana I; Thomson, Lynn M; Garden, Karen E; Williams, Patricia A; Richardson, Anthony J; Ross, Alexander W

2016-01-01

Dietary constituents that suppress appetite, such as dietary fibre and protein, may aid weight loss in obesity. The soluble fermentable dietary fibre pectin promotes satiety and decreases adiposity in diet-induced obese rats but effects of increased protein are unknown. Adult diet-induced obese rats reared on high fat diet (45% energy from fat) were given experimental diets ad libitum for 4 weeks (n = 8/group): high fat control, high fat with high protein (40% energy) as casein or pea protein, or these diets with added 10% w/w pectin. Dietary pectin, but not high protein, decreased food intake by 23% and induced 23% body fat loss, leading to 12% lower final body weight and 44% lower total body fat mass than controls. Plasma concentrations of satiety hormones PYY and total GLP-1 were increased by dietary pectin (168% and 151%, respectively) but not by high protein. Plasma leptin was decreased by 62% on pectin diets and 38% on high pea (but not casein) protein, while plasma insulin was decreased by 44% on pectin, 38% on high pea and 18% on high casein protein diets. Caecal weight and short-chain fatty acid concentrations in the caecum were increased in pectin-fed and high pea protein groups: caecal succinate was increased by pectin (900%), acetate and propionate by pectin (123% and 118%, respectively) and pea protein (147% and 144%, respectively), and butyrate only by pea protein (309%). Caecal branched-chain fatty acid concentrations were decreased by pectin (down 78%) but increased by pea protein (164%). Therefore, the soluble fermentable fibre pectin appeared more effective than high protein for increasing satiety and decreasing caloric intake and adiposity while on high fat diet, and produced a fermentation environment more likely to promote hindgut health. Altogether these data indicate that high fibre may be better than high protein for weight (fat) loss in obesity.

Pectinmethylesterases (PME) and pectinmethylesterase inhibitors (PMEI) enriched during phloem fiber development in flax (Linum usitatissimum).

Science.gov (United States)

Pinzon-Latorre, David; Deyholos, Michael K

2014-01-01

Flax phloem fibers achieve their length by intrusive-diffusive growth, which requires them to penetrate the extracellular matrix of adjacent cells. Fiber elongation therefore involves extensive remodelling of cell walls and middle lamellae, including modifying the degree and pattern of methylesterification of galacturonic acid (GalA) residues of pectin. Pectin methylesterases (PME) are important enzymes for fiber elongation as they mediate the demethylesterification of GalA in muro, in either a block-wise fashion or in a random fashion. Our objective was to identify PMEs and PMEIs that mediate phloem fiber elongation in flax. For this purpose, we measured transcript abundance of candidate genes at nine different stages of stem and fiber development and found sets of genes enriched during fiber elongation and maturation as well as during xylem development. We expressed one of the flax PMEIs in E. coli and demonstrated that it was able to inhibit most of the native PME activity in the upper portion of the flax stem. These results identify key genetic components of the intrusive growth process and define targets for fiber engineering and crop improvement.

Fingerprinting complex pectins by chromatographic separation combined with ELISA detection

NARCIS (Netherlands)

Verhoef, R.P.; Lu, Y.; Knox, J.P.; Voragen, A.G.J.; Schols, H.A.

2009-01-01

Enzyme-resistant pectin or modified hairy regions were subjected to size exclusion (HPSEC) and weak anion exchange (WAX) chromatography. Fractions collected after separation were tested for the presence of different pectic epitopes using the monoclonal antibodies LM2, LM5, LM6, and JIM7. Separation

Citric pectin. Effect of steam haulage in the extraction and of different drying methods

International Nuclear Information System (INIS)

Estrada E, Amparo; Lopez O, Beatriz

1998-01-01

It is carried out this investigation with the purpose of determining the effects of steam haulage and of two drying methods in extracted pectin of orange shell, using the residuals of the machine processor of the Caldas region, that it uses the system In Line in the obtaining of the juice for the effect. The essential oils were eliminated the pericarp with haulage of steam, the pectin was extracted with solution to 50% of citric acid and hexametaphosphate of sodium to 0.2%. For shell weight the extraction temperature was of 80 applied during one hour and the pH of 3.4. The pectin was characterized extracted by means of determinations of humidity, ashy, nitrogen, methoxyl percentage, anhidrogalacturonic acid, pH, and acidity. Their behavior is also evaluated by means of determinations that are carried out to the gel with them prepared as its hardness, time and low temperature. They use a totally aleatory statistical design in factorial arrangement 3x2, three treatments: T1 flavedo and albedo with haulage of steam, T2 albedo with steam haulage and T3 albedo without steam haulage and two drying methods, with hot air and with microwaves. The results were analyzed by means of ANDEVA and tests of comparison of Tuckey and Scheff at a level of probability of 95%. They concluded that the steam haulage doesn't have significant influence in the characteristics of the obtained product while, the drying for microwaves influenced significantly in a positive way in the characteristics of the extracted pectin

Physical Characterization Of High Amylose/Pectin Mixtures Cross-Linked With Sodium Trimetaphosphate

International Nuclear Information System (INIS)

Carbinatto, F.M.; Cury, B.S.F.; Evangelista, R.C.

2010-01-01

Some researches have reported that pectin and high amylose mixtures presented superior mechanical properties in relation to those of the isolated polymers. In this work, mixtures at different ratios (1:4; 1:1) of pectin and high amylose were crosslinked with sodium trimetaphosphate at different degrees by varying reaction conditions. All samples were characterized by rheological and X-ray diffraction analyses. Samples without cross-linker were prepared as control. The oscillatory dynamic tests showed that all samples exhibited predominant elastic behavior, although cross-linked samples presented higher G' values, suggesting that crosslinking by phosphorylation resulted in more strength structures. The diffractograms showed that cross-linked samples underwent structural modifications that resulted in increase of crystallinity due to cross-linking process. (author)

Non-covalent conjugation of cutinase from Fusarium sp. ICT SAC1 with pectin for enhanced stability: Process minutiae, kinetics, thermodynamics and structural study.

Science.gov (United States)

Muley, Abhijeet B; Chaudhari, Sandeep A; Singhal, Rekha S

2017-09-01

Cutinase, a member of α/β-fold hydrolase family possess potentially diverse applications in several industrial processes and products. The present work aims towards thermo-stabilization of cutinase from novel source Fusarium sp. ICT SAC1 via non-covalent interaction with polysaccharides. Although all six polysaccharides chosen for study enhanced the thermal stability, pectin was found to be most promising. The interaction protocol for cutinase with pectin was optimized sequentially with respect to the ratio of enzyme to pectin, solution pH, and buffer strength. Cutinase-pectin conjugate under optimized conditions (1:12, pH-6.5, 50mM) showed enhanced thermal stability as evident from lower inactivation rate constant, higher half-life and D-value within the 40-55°C. A slender rise in K m and V max values and enhanced thermodynamic parameters of cutinase-pectin conjugate were observed after non-covalent interaction. Entropy values were 1.5-fold higher for cutinase-pectin conjugate at each temperature suggesting an upsurge in number of protein molecules in a transition activated state. Positive values of entropy for both forms of cutinase suggested a rise in disordered conformation. Noticeable conformational changes in cutinase after conjugation with pectin were confirmed by FTIR as well as fluorescence emission spectra. An increment in helix to turn conversion was observed in complexed cutinase vis-à-vis free cutinase. Copyright © 2017 Elsevier B.V. All rights reserved.

Pectin of Prunus domestica L. alters sulfated structure of cell-surface heparan sulfate in differentiated Caco-2 cells through stimulation of heparan sulfate 6-O-endosulfatase-2.

Science.gov (United States)

Nishida, Mitsutaka; Murata, Kazuma; Kanamaru, Yoshihiro; Yabe, Tomio

2014-01-01

Although previous reports have suggested that pectin induces morphological changes of the small intestine in vivo, the molecular mechanisms have not been elucidated. As heparan sulfate plays important roles in development of the small intestine, to verify the involvement of heparan sulfate (HS) in the pectin-induced morphological changes of the small intestine, the effects of pectin from Prunus domestica L. on cell-surface HS were investigated using differentiated Caco-2 cells. Disaccharide compositional analysis revealed that sulfated structures of HS were markedly changed by pectin administration. Real-time RT-PCR showed that pectin upregulated human HS 6-O-endosulfatase-2 (HSulf-2) expression and markedly inhibited HSulf-1 expression. Furthermore, inhibition analysis suggested that pretreatment with fibronectin III1C fragment, RGD peptide, and ERK1/2 inhibitor suppressed pectin-induced HSulf-2 expression. These observations indicate that pectin induced the expression of HSulf-2 through the interaction with fibronectin, α5β1 integrin, and ERK1/2, thereby regulating the sulfated structure of HS on differentiated Caco-2 cells.

Pectin/zein hydrogels for the delivery of drugs and nutrients

Science.gov (United States)

Two pectin/zein coacervates were prepared with either calcium ions or zinc ions. Piroxicam, a non-steroidal anti-inflammatory drug, was encapsulated. It was found that at lower solution pH the release of piroxicam displayed a near zero order kinetics, whether the coacervates were cross-linked with c...

Prebiotic potential of pectin and pectic oligosaccharides to promote anti-inflammatory commensal bacteria in the human colon

DEFF Research Database (Denmark)

Chung, Wing Sun Faith; Meijerink, Marjolein; Zeuner, Birgitte

2017-01-01

Dietary plant cell wall carbohydrates are important in modulating the composition and metabolism of the complex gut microbiota, which can impact on health. Pectin is a major component of plant cell walls. Based on studies in model systems and available bacterial isolates and genomes, the capacity...... suggest the potential to explore further the prebiotic potential of pectin and its derivatives to re-balance the microbiota towards an anti-inflammatory profile....

Pectin-zinc-chitosan-polyethylene glycol colloidal nano-suspension as a food grade carrier for colon targeted delivery of resveratrol

DEFF Research Database (Denmark)

Andishmand, Hashem; Mahnaz Tabibiazar; Mohammadifar, Mohammad Amin

2017-01-01

The aim of the present study was to develop chitosan-zinc-pectinate-polyethylene glycol (PEG) nanoparticles (NPs) for colon-targeted delivery of resveratrol. The effects of pectin:ZnCl2:chitosan (PZnC) % w/v, pH and ionic strength of media, and addition of PEG on the colloidal stability and release...

Cellulose-Pectin Spatial Contacts Are Inherent to Never-Dried Arabidopsis Primary Cell Walls: Evidence from Solid-State Nuclear Magnetic Resonance1[OPEN

Science.gov (United States)

Wang, Tuo; Park, Yong Bum; Hong, Mei

2015-01-01

The structural role of pectins in plant primary cell walls is not yet well understood because of the complex and disordered nature of the cell wall polymers. We recently introduced multidimensional solid-state nuclear magnetic resonance spectroscopy to characterize the spatial proximities of wall polysaccharides. The data showed extensive cross peaks between pectins and cellulose in the primary wall of Arabidopsis (Arabidopsis thaliana), indicating subnanometer contacts between the two polysaccharides. This result was unexpected because stable pectin-cellulose interactions are not predicted by in vitro binding assays and prevailing cell wall models. To investigate whether the spatial contacts that give rise to the cross peaks are artifacts of sample preparation, we now compare never-dried Arabidopsis primary walls with dehydrated and rehydrated samples. One-dimensional 13C spectra, two-dimensional 13C-13C correlation spectra, water-polysaccharide correlation spectra, and dynamics data all indicate that the structure, mobility, and intermolecular contacts of the polysaccharides are indistinguishable between never-dried and rehydrated walls. Moreover, a partially depectinated cell wall in which 40% of homogalacturonan is extracted retains cellulose-pectin cross peaks, indicating that the cellulose-pectin contacts are not due to molecular crowding. The cross peaks are observed both at −20°C and at ambient temperature, thus ruling out freezing as a cause of spatial contacts. These results indicate that rhamnogalacturonan I and a portion of homogalacturonan have significant interactions with cellulose microfibrils in the native primary wall. This pectin-cellulose association may be formed during wall biosynthesis and may involve pectin entrapment in or between cellulose microfibrils, which cannot be mimicked by in vitro binding assays. PMID:26036615

Pectins, Hemicelluloses and Celluloses Show Specific Dynamics in the Internal and External Surfaces of Grape Berry Skin During Ripening.

Science.gov (United States)

Fasoli, Marianna; Dell'Anna, Rossana; Dal Santo, Silvia; Balestrini, Raffaella; Sanson, Andrea; Pezzotti, Mario; Monti, Francesca; Zenoni, Sara

2016-06-01

Grapevine berry skin is a complex structure that contributes to the final size and shape of the fruit and affects its quality traits. The organization of cell wall polysaccharides in situ and their modification during ripening are largely uncharacterized. The polymer structure of Corvina berry skin, its evolution during ripening and related modifying genes were determined by combing mid-infrared micro-spectroscopy and multivariate statistical analysis with transcript profiling and immunohistochemistry. Spectra were acquired in situ using a surface-sensitive technique on internal and external sides of the skin without previous sample pre-treatment, allowing comparison of the related cell wall polymer dynamics. The external surface featured cuticle-related bands; the internal surface showed more adsorbed water. Application of surface-specific normalization revealed the major molecular changes related to hemicelluloses and pectins in the internal surface and to cellulose and pectins in the external surface and that they occur between mid-ripening and full ripening in both sides of the skin. Transcript profiling of cell wall-modifying genes indicated a general suppression of cell wall metabolism during ripening. Genes related to pectin metabolism-a β-galactosidase, a pectin(methyl)esterase and a pectate lyase-and a xyloglucan endotransglucosylase/hydrolase, involved in hemicellulose modification, showed enhanced expression. In agreement with Fourier transform infrared spectroscopy, patterns due to pectin methyl esterification provided new insights into the relationship between pectin modifications and the associated transcript profile during skin ripening. This study proposes an original description of polymer dynamics in grape berries during ripening, highlighting differences between the internal and external sides of the skin. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For

Enzymatic extraction of pectin from artichoke (Cynara scolymus L.) by-products using Celluclast®1.5L.

Science.gov (United States)

Sabater, Carlos; Corzo, Nieves; Olano, Agustín; Montilla, Antonia

2018-06-15

The aim of this study was to optimise pectin extraction from artichoke by-products with Celluclast ® 1.5L using an experimental design analysed by response-surface methodology (RSM). The variables optimised were artichoke by-product powder concentration (2-7%, X 1 ), enzyme dose (2.2-13.3 U g -1 , X 2 ) and extraction time (6-24 h, X 3 ). The variables studied were galacturonic acid (GalA) (R 2 93.9) and pectic neutral sugars (R 2 92.8) content and pectin yield (R 2 88.6). In the optimum extraction conditions (X 1  = 6.5%; X 2  = 10.1 U g -1 ; X 3  = 27.2 h), pectin yield was 176 mgg -1 dry matter (DM). Considering 27.2 h of treatment as the +α value given by the design, the extraction time was increased up to 48 h obtaining a yield of 221 mg g -1 DM. The enzymatic method optimised allows obtaining artichoke pectin with good yield, high GalA (720 mg g -1 DM) and arabinose (127.6mgg -1 DM) contents and degree of methylation of 19.5%. Copyright © 2018 Elsevier Ltd. All rights reserved.

Insights into the swelling process and drug release mechanisms from cross-linked pectin/high amylose starch matrices

Directory of Open Access Journals (Sweden)

Fernanda M. Carbinatto

2014-02-01

Full Text Available Cross-linked pectin/high amylose mixtures were evaluated as a new excipient for matrix tablets formulations, since the mixing of polymers and cross-linking reaction represent rational tools to reach materials with modulated and specific properties that meet specific therapeutic needs. Objective: In this work the influence of polymer ratio and cross-linking process on the swelling and the mechanism driving the drug release from swellable matrix tablets prepared with this excipient was investigated. Methods: Cross-linked samples were characterized by their micromeritic properties (size and shape, density, angle of repose and flow rate and liquid uptake ability. Matrix tablets were evaluated according their physical properties and the drug release rates and mechanisms were also investigated. Results: Cross-linked samples demonstrated size homogeneity and irregular shape, with liquid uptake ability insensible to pH. Cross-linking process of samples allowed the control of drug release rates and the drug release mechanism was influenced by both polymer ratio and cross-linking process. The drug release of samples with minor proportion of pectin was driven by an anomalous transport and the increase of the pectin proportion contributed to the erosion of the matrix. Conclusion: The cross-linked mixtures of high amylose and pectin showed a suitable excipient for slowing the drug release rates.

Opuntia ficus indica peel derived pectin mediated hydroxyapatite nanoparticles: Synthesis, spectral characterization, biological and antimicrobial activities

Science.gov (United States)

Gopi, D.; Kanimozhi, K.; Kavitha, L.

2015-04-01

In the present study, we have adapted a facile and efficient green route for the synthesis of HAP nanoparticles using pectin as a template which was extracted from the peel of prickly pear (Opuntia ficus indica) fruits. The concentration of pectin plays a major role in the behavior of crystallinity, purity, morphology as well as biological property of the as-synthesized HAP nanoparticles. The extracted pectin and the as-synthesized nanoparticles were characterized by various analytical techniques. The in vitro apatite formation on the surface of the as-synthesized nanoparticles in simulated body fluid (SBF) for various days showed an enhanced bioactivity. Also, the antimicrobial activity was investigated using various microorganisms. All the results revealed the formation of pure, low crystalline and discrete granular like HAP nanoparticles of size around 25 nm with enhanced biological and antimicrobial activities. Hence the as-synthesized nanoparticles can act as a better bone regenerating material in the field of biomedicine.

Opuntia ficus indica peel derived pectin mediated hydroxyapatite nanoparticles: synthesis, spectral characterization, biological and antimicrobial activities.

Science.gov (United States)

Gopi, D; Kanimozhi, K; Kavitha, L

2015-04-15

In the present study, we have adapted a facile and efficient green route for the synthesis of HAP nanoparticles using pectin as a template which was extracted from the peel of prickly pear (Opuntia ficus indica) fruits. The concentration of pectin plays a major role in the behavior of crystallinity, purity, morphology as well as biological property of the as-synthesized HAP nanoparticles. The extracted pectin and the as-synthesized nanoparticles were characterized by various analytical techniques. The in vitro apatite formation on the surface of the as-synthesized nanoparticles in simulated body fluid (SBF) for various days showed an enhanced bioactivity. Also, the antimicrobial activity was investigated using various microorganisms. All the results revealed the formation of pure, low crystalline and discrete granular like HAP nanoparticles of size around 25 nm with enhanced biological and antimicrobial activities. Hence the as-synthesized nanoparticles can act as a better bone regenerating material in the field of biomedicine. Copyright © 2015 Elsevier B.V. All rights reserved.

Pectin- and gelatin-based film: effect of gamma irradiation on the mechanical properties and biodegradation

Energy Technology Data Exchange (ETDEWEB)

Jo, Cheorun; Kang, Hojin; Lee, Na Young; Kwon, Joong Ho; Byun, Myung Woo E-mail: mwbyun@kaeri.re.kr

2005-04-01

Agricultural by-products, pectin and gelatin, were used to prepare a biodegradable film. The film casting solution including the pectin and gelatin was irradiated at 0, 10, 20, and 30 kGy to investigate the irradiation effect on the mechanical properties of the film. The tensile strength of the 10 kGy-irradiated film was the highest among the treatments but the elongation at break, water vapour permeability, and swelling ratio were the lowest. Hunter color L*- and a*-values decreased but the b*-value increased as the irradiation dose increased. The total organic carbon content produced from the Paenibacillus polymyxa and Pseudomonas aeruginosa also showed that the film of 10 kGy-irradiated was lower than those of 0, 20, and 30 kGy-irradiated films. In conclusion, irradiation of the film casting solution at 10 kGy increased the mechanical properties of the pectin and gelatin based film. To manufacture the film by agricultural by-products, however, the irradiation dose of the film casting solution should be determined to achieve better mechanical properties.

Expression of mung bean pectin acetyl esterase in potato tubers: effect on acetylation of cell wall polymers and tuber mechanical properties.

Science.gov (United States)

Orfila, Caroline; Dal Degan, Florence; Jørgensen, Bodil; Scheller, Henrik Vibe; Ray, Peter M; Ulvskov, Peter

2012-07-01

A mung bean (Vigna radiata) pectin acetyl esterase (CAA67728) was heterologously expressed in tubers of potato (Solanum tuberosum) under the control of the granule-bound starch synthase promoter or the patatin promoter in order to probe the significance of O-acetylation on cell wall and tissue properties. The recombinant tubers showed no apparent macroscopic phenotype. The enzyme was recovered from transgenic tubers using a high ionic strength buffer and the extract was active against a range of pectic substrates. Partial in vivo de-acetylation of cell wall polysaccharides occurred in the transformants, as shown by a 39% decrease in the degree of acetylation (DA) of tuber cell wall material (CWM). Treatment of CWM using a combination of endo-polygalacturonase and pectin methyl esterase extracted more pectin polymers from the transformed tissue compared to wild type. The largest effect of the pectin acetyl esterase (68% decrease in DA) was seen in the residue from this extraction, suggesting that the enzyme is preferentially active on acetylated pectin that is tightly bound to the cell wall. The effects of acetylation on tuber mechanical properties were investigated by tests of failure under compression and by determination of viscoelastic relaxation spectra. These tests suggested that de-acetylation resulted in a stiffer tuber tissue and a stronger cell wall matrix, as a result of changes to a rapidly relaxing viscoelastic component. These results are discussed in relation to the role of pectin acetylation in primary cell walls and its implications for industrial uses of potato fibres.

Kinetics of piroxicam release from low-methylated pectin/zein hydrogel microspheres

Science.gov (United States)

The kinetics of a model drug (piroxicam) release from pectin/zein hydrogel microspheres was studied under conditions simulating the gastrointestinal tract. It is established that the rate-limiting step in the release mechanism is drug diffusion out of the microspheres rather than its dissolution. ...

Enzyme catalyzed oxidative gelation of sugar beet pectin: Kinetics and rheology

DEFF Research Database (Denmark)

Abang Zaidel, Dayang Norulfairuz; Chronakis, Ioannis S.; Meyer, Anne S.

2012-01-01

Sugar beet pectin (SBP) is a marginally utilized co-processing product from sugar production from sugar beets. In this study, the kinetics of oxidative gelation of SBP, taking place via enzyme catalyzed cross-linking of ferulic acid moieties (FA), was studied using small angle oscillatory...

Understanding the Biological Roles of Pectins in Plants through Physiological and Functional Characterizations of Plant and Fungal Mutants

DEFF Research Database (Denmark)

Stranne, Maria

The plant cell wall is a dynamic structure and it is involved in regulating a number of physiological features of plants such as physical strength, growth, cell differentiation, intercellular communication, water movement and defense responses. Pectins constitute a major class of plant cell wall...... polysaccharides and consist of backbones rich in galacturonic acids, which are decorated with a range of functional groups including acetyl esters and arabinan sidechains. Although much effort has been made to uncover biological functions of pectins in plants and remarkable progresses have taken place, many...... aspects remain elusive. Studies described in this thesis aimed at gaining new insights into the biological roles of pectin acetylation and arabinosylation in the model plant Arabidopsis thaliana. The thesis consists of four chapters: physiological characterization of cell wall mutants affected in cell...

Comparative effect of amidated pectin and psyllium on cholesterol homeostasis in rats

Czech Academy of Sciences Publication Activity Database

Marounek, Milan; Volek, Z.; Skřivanová, E.; Tůma, J.; Dušková, D.

2010-01-01

Roč. 5, č. 3 (2010), s. 299-303 ISSN 1895-104X Institutional research plan: CEZ:AV0Z50450515 Keywords : Cholesterol homeostazis * Pectin * Psyllium Subject RIV: GH - Livestock Nutrition Impact factor: 0.685, year: 2010

Pectin methyl esterase activity in apple and orange pulps

International Nuclear Information System (INIS)

Abdullaev, A.; Djumaev, B.B.; Djumaev, N.B.; Mukhidinov, Z.K.

2008-01-01

The results of pectin methyl esterase activity from apple, orange pulp and orange peel depending of ph and temperature are discussed. It's shown that the methyl esterase activity form apple and orange pulps higher in range of temperatures from +37...+60 d ig C . The analysis of dependence of its activity from ph has shown that in both case the enzyme activity increase with increase of ph

Hydrolysis-extraction of apple proto pectins in dynamic mode

International Nuclear Information System (INIS)

Bobodzhonova, G.N.; Gorshkova, R.M.; Makhkamov, Kh.K.

2013-01-01

The article describes a hydrolysis process of apple husks by using dynamics regime of hydrolysis. It's shown that application of dynamics method positively influences on the pectin yields and its main parameters. It was defined that by dynamics regime of hydrolysis-extraction of apple husks it is possible to obtain qualitative products with high yield at a mild ph value of medium of hydrolysing agent.

Inhibition of pectin methyl esterase activity by green tea catechins.

Science.gov (United States)

Lewis, Kristin C; Selzer, Tzvia; Shahar, Chen; Udi, Yael; Tworowski, Dmitry; Sagi, Irit

2008-10-01

Pectin methyl esterases (PMEs) and their endogenous inhibitors are involved in the regulation of many processes in plant physiology, ranging from tissue growth and fruit ripening to parasitic plant haustorial formation and host invasion. Thus, control of PME activity is critical for enhancing our understanding of plant physiological processes and regulation. Here, we report on the identification of epigallocatechin gallate (EGCG), a green tea component, as a natural inhibitor for pectin methyl esterases. In a gel assay for PME activity, EGCG blocked esterase activity of pure PME as well as PME extracts from citrus and from parasitic plants. Fluorometric tests were used to determine the IC50 for a synthetic substrate. Molecular docking analysis of PME and EGCG suggests close interaction of EGCG with the catalytic cleft of PME. Inhibition of PME by the green tea compound, EGCG, provides the means to study the diverse roles of PMEs in cell wall metabolism and plant development. In addition, this study introduces the use of EGCG as natural product to be used in the food industry and agriculture.

A Comprehensive Study on Fast Dispersible and Slow-Releasing Characteristic of Orange Peel Pectin in Relation to Established Synthetic Polymer.

Science.gov (United States)

Srivastava, Pranati; Singh, Mahendra; Bhargava, Shilpi

2017-10-01

In the present work, the method to extract, isolate, and characterize orange peel pectin using soxhlation, and thereafter, the use of this polymer-polymer in the formulation of fast dispersable and slow-releasing tablet has been studied. Thereafter, the evaluation and comparison of fast dispersible/slow-releasing tablets using orange peel pectin versus prepared using sodium starch glycolate (SSG) were carried out. In the present investigation, extraction methodology was employed for isolation of pectin from orange peels. Four different batches with each polymer were prepared with varying concentration of superdisintegrant and bulking agent using diclofenac sodium as model drug. Diclofenac sodium stands as easily available, cheap, and good candidate to demonstrate disintegrant property. The formulation involved wet granulation method for the preparation of tablets of each batch. The tablets were evaluated for hardness, friability, thickness, wetting time, deaggregation time, and in vitro release characteristic data. It was observed that parameters for batch O2* were comparable with that of synthetic superdisintegrant. This batch gave around 92.12% drug release in period of 90 min. The study showed that orange peel pectin could be a potential candidate for formulation of orodispersible dosage forms in competence to SSG, which is established superdisintegrant. The results led to the conclusion that the use of natural polymers in formulation of pharmaceutical dosage form can be put into practice on industrial scale meeting the similar requirements as done by synthetic polymers. The present work aims to demonstrate and establish the use of naturally derived polymer, i.e., orange peel pectin as a superdisintegrant. The extraction methodology has been discussed followed by comparative analysis with a synthetic polymer. Abbreviations used: O1-O2: Batches Containing Orange peel pectin, S1-S2: Batches containing SSG, SSG: Sodium starch glycolate, NDDS: Novel drug delivery

Isolation and characterization of a tomato non-specific lipid transfer protein involved in polygalacturonase-mediated pectin degradation.

Science.gov (United States)

Tomassen, Monic M M; Barrett, Diane M; van der Valk, Henry C P M; Woltering, Ernst J

2007-01-01

An important aspect of the ripening process of tomato fruit is softening. Softening is accompanied by hydrolysis of the pectin in the cell wall by pectinases, causing loss of cell adhesion in the middle lamella. One of the most significant pectin-degrading enzymes is polygalacturonase (PG). Previous reports have shown that PG in tomato may exist in different forms (PG1, PG2a, PG2b, and PGx) commonly referred to as PG isoenzymes. The gene product PG2 is differentially glycosylated and is thought to associate with other proteins to form PG1 and PGx. This association is thought to modulate its pectin-degrading activity in planta. An 8 kDa protein that is part of the tomato PG1 multiprotein complex has been isolated, purified, and functionally characterized. This protein, designated 'activator' (ACT), belongs to the class of non-specific lipid transfer proteins (nsLTPs). ACT is capable of 'converting' the gene product PG2 into a more active and heat-stable form, which increases PG-mediated pectin degradation in vitro and stimulates PG-mediated tissue breakdown in planta. This finding suggests a new, not previously identified, function for nsLTPs in the modification of hydrolytic enzyme activity. It is proposed that ACT plays a role in the modulation of PG activity during tomato fruit softening.

A history of salt.

Science.gov (United States)

Cirillo, M; Capasso, G; Di Leo, V A; De Santo, N G

1994-01-01

The medical history of salt begins in ancient times and is closely related to different aspects of human history. Salt may be extracted from sea water, mineral deposits, surface encrustations, saline lakes and brine springs. In many inland areas, wood was used as a fuel source for evaporation of brine and this practice led to major deafforestation in central Europe. Salt played a central role in the economies of many regions, and is often reflected in place names. Salt was also used as a basis for population censuses and taxation, and salt monopolies were practised in many states. Salt was sometimes implicated in the outbreak of conflict, e.g. the French Revolution and the Indian War of Independence. Salt has also been invested with many cultural and religious meanings, from the ancient Egyptians to the Middle Ages. Man's innate appetite for salt may be related to his evolution from predominantly vegetarian anthropoids, and it is noteworthy that those people who live mainly on protein and milk or who drink salty water do not generally salt their food, whereas those who live mainly on vegetables, rice and cereals use much more salt. Medicinal use tended to emphasize the positive aspects of salt, e.g. prevention of putrefaction, reduction of tissue swelling, treatment of diarrhea. Evidence was also available to ancient peoples of its relationship to fertility, particularly in domestic animals. The history of salt thus represents a unique example for studying the impact of a widely used dietary substance on different important aspects of man's life, including medical philosophy.

Pre-Harvest Dropped Kinnow ( Citrus reticulata Blanco) Waste Management through the Extraction of Naringin and Pectin from their Peels using Indigenous Resin

Science.gov (United States)

Laxmi Deepak Bhatlu, M.; Katiyar, Prashant; Singh, Satya Vir; Verma, Ashok Kumar

2016-09-01

About 10-20 % kinnow fruits are dropped in preharvest stage which are waste and are problem to farmer as these create nuisance by rotting and insect rearing ground. The peels of these dropped fruits as well as peels from kinnow processing may be good source of naringin and pectin. Naringin is used in pharmaseutics while pectin is used in food industry. For recovery of naringin and pectn, peels of preharvest dropped kinnow fruits were boiled in water. The extract was passed through macroporus polymeric adsorbent resin Indion PA 800, naringin was adsorbed on it. The adsorbed naringin was desorbed with ethanol. This solution was passed through membrane filter and filtrate was evaporated to obtain naringin. The extract remaining after adsorption of naringin was used to recover pectin using acid extraction method. The recovery of naringin and pectin was about 52 and 58 % respectively. The naringin finally obtained had 91-93 % purity.

Evaluation of the use of pectin among children living on the territories contaminated by cesium. Situation and critical analysis of publications

International Nuclear Information System (INIS)

Jourdain, J.R.; Dublineau, I.; Phan, G.

2005-01-01

This report includes four parts. The first one gives the situation of knowledge on the biological effects of pectin in human nutrition and in case of exposure to heavy metals. The second part presents an analysis of publications devoted to biological effects of pectins in case of chronic intake of radioisotopes.The third part is a synthesis that gives the principal teaching of this analysis. The last part presents the propositions of I.R.S.N relative to future works and studies that it would be interesting to launch in order to complete the knowledge relative to the use of pectin in the case of chronic intake of radioisotopes. (N.C.)

Quantitative and qualitative characteristics of cell wall components and prenyl lipids in the leaves of Tilia x euchlora trees growing under salt stress.

Science.gov (United States)

Milewska-Hendel, Anna; Baczewska, Aneta H; Sala, Katarzyna; Dmuchowski, Wojciech; Brągoszewska, Paulina; Gozdowski, Dariusz; Jozwiak, Adam; Chojnacki, Tadeusz; Swiezewska, Ewa; Kurczynska, Ewa

2017-01-01

The study was focused on assessing the presence of arabinogalactan proteins (AGPs) and pectins within the cell walls as well as prenyl lipids, sodium and chlorine content in leaves of Tilia x euchlora trees. The leaves that were analyzed were collected from trees with and without signs of damage that were all growing in the same salt stress conditions. The reason for undertaking these investigations was the observations over many years that indicated that there are trees that present a healthy appearance and trees that have visible symptoms of decay in the same habitat. Leaf samples were collected from trees growing in the median strip between roadways that have been intensively salted during the winter season for many years. The sodium content was determined using atomic spectrophotometry, chloride using potentiometric titration and poly-isoprenoids using HPLC/UV. AGPs and pectins were determined using immunohistochemistry methods. The immunohistochemical analysis showed that rhamnogalacturonans I (RG-I) and homogalacturonans were differentially distributed in leaves from healthy trees in contrast to leaves from injured trees. In the case of AGPs, the most visible difference was the presence of the JIM16 epitope. Chemical analyses of sodium and chloride showed that in the leaves from injured trees, the level of these ions was higher than in the leaves from healthy trees. Based on chromatographic analysis, four poly-isoprenoid alcohols were identified in the leaves of T. x euchlora. The levels of these lipids were higher in the leaves from healthy trees. The results suggest that the differences that were detected in the apoplast and symplasm may be part of the defensive strategy of T. x euchlora trees to salt stress, which rely on changes in the chemical composition of the cell wall with respect to the pectic and AGP epitopes and an increased synthesis of prenyl lipids.

Structure of pectic polysaccharides from sunflower salts-soluble fraction

Science.gov (United States)

The manuscript discusses the structural features of pectin polysaccharides extracted from seedless sunflower head residues. The analysis using 1H, 13C and two-dimensional gHSQC NMR showed various numbers of methyl and hydroxyl groups attached to the anomeric carbons in the pectin backbone at differe...

Ileal microbiota of growing pigs fed different dietary calcium phosphate levels and phytase content and subjected to ileal pectin infusion.

Science.gov (United States)

Metzler-Zebeli, B U; Vahjen, W; Baumgärtel, T; Rodehutscord, M; Mosenthin, R

2010-01-01

Two experiments with growing pigs were conducted to determine the effects of dietary P and Ca levels, phytase supplementation, and ileal pectin infusion on changes in bacterial populations in the ileum and on ileal and fecal fermentation patterns. Growing pigs (BW 30.1 +/- 1.3 kg) were fitted with simple T-cannulas at the distal ileum and were fed a low-P corn-soybean meal control diet (3 g of P/kg), or the control diet supplemented with either 15 g of monocalcium phosphate (MCP)/kg (Exp. 1) or 1,000 phytase units of phytase/kg (Exp. 2). Daily infusion treatments consisted of either 60 g of pectin dissolved in 1.8 L of demineralized water or 1.8 L of demineralized water as a control infusion, infused via the ileal cannula. In each experiment, 8 barrows were assigned to 4 dietary treatments according to a double incomplete 4 x 2 Latin square design. The dietary treatments in Exp. 1 were the control diet with water infusion, the control diet with pectin infusion, the MCP diet with water infusion, or the MCP diet with pectin infusion. In Exp. 2, the pigs received the same control treatments as in Exp. 1 and the phytase diet in combination with water or pectin infusion. Gene copy numbers of total bacteria, Lactobacillus spp., Lactobacillus reuteri, Lactobacillus amylovorus/Lactobacillus sobrius, Lactobacillus mucosae, Enterococcus spp., Enterococcus faecium, Enterococcus faecalis, bifidobacteria, the Clostridium coccoides cluster, the Clostridium leptum cluster, the Bacteroides-Prevotella-Porphyrmonas group, and Enterobacteriaceae were determined by quantitative PCR in DNA extracts of ileal digesta. In Exp. 1, addition of MCP reduced ileal gene copy numbers of Enterococcus spp. (P = 0.048), E. faecium (P = 0.015), and the C. leptum cluster (P = 0.028), whereas pectin infusion enhanced (P = 0.008) ileal d-lactate concentration. In Exp. 2, supplemental phytase led to greater ileal gene copy numbers of the C. coccoides (P = 0.041) and C. leptum (P = 0.048) clusters and

QSPR study of the retention/release property of odorant molecules in pectin gels using statistical methods

Directory of Open Access Journals (Sweden)

Assia Belhassan

2017-11-01

Full Text Available The ACD/ChemSketch, MarvinSketch, and ChemOffice programmes were used to calculate several molecular descriptors of 51 odorant molecules (15 alcohols, 11 aldehydes, 9 ketones and 16 esters. The best descriptors were selected to establish the Quantitative Structure-Property Relationship (QSPR of the retention/release property of odorant molecules in pectin gels using Principal Components Analysis (PCA, Multiple Linear Regression (MLR, Multiple Non-linear Regression (MNLR and Artificial Neural Network (ANN methods We propose a quantitative model based on these analyses. PCA has been used to select descriptors that exhibit high correlation with the retention/release property. The MLR method yielded correlation coefficients of 0.960 and 0.958 for PG-0.4 (pectin concentration: 0.4% w/w and PG-0.8 (pectin concentration: 0.8% w/w media, respectively. Internal and external validations were used to determine the statistical quality of the QSPR of the two MLR models. The MNLR method, considering the relevant descriptors obtained from the MLR, yielded correlation coefficients of 0.978 and 0.975 for PG-0.4 and PG-0.8 media, respectively. The applicability domain of MLR models was investigated using simple and leverage approaches to detect outliers and outside compounds. The effects of different descriptors on the retention/release property are described, and these descriptors were used to study and design new compounds with higher and lower values of the property than the existing ones. Keywords: Odorant Molecules, Retention/Release, Pectin Gels, Quantitative Structure Property Relationship, Multiple Linear Regression, Artificial Neural Network

Thermochemical Properties of Nicotine Salts

Directory of Open Access Journals (Sweden)

Riggs DM

2014-12-01

Full Text Available The thermal gravimetric analysis (TGA and differential scanning calorimetry (DSC results presented in this report clearly show that the thermal stability and the endothermic peak nicotine release temperatures are different for different nicotine salts and these temperatures appear to be linked to the general microstructural details of the salt itself. In addition, the peak nicotine release temperatures are highly dependent upon the sample size used. The heat of vaporization for neat (non-protonated nicotine is also sample-size dependent. The TGA data showed that the least stable of the salts tested at elevated temperatures was the liquid salt nicotine triacetate followed by the crystalline materials (e.g., nicotine gallate and finally, the amorphous salts (e.g., nicotine alginate. The DSC results revealed that the liquid and crystalline salts exhibit nicotine release endotherms that are strongly related to the sample weight being tested. The amorphous salts show nicotine endotherm peak temperatures that are nearly independent of the sample weight. The range of peak nicotine release temperatures varied depending upon the specific salts and the sample size from 83 oC to well over 200 oC. Based on these results, the evolution of nicotine from the nicotine salt should be expected to vary based on the composition of the salt, the details of its microstructure, and the amount of nicotine salt tested.

The simplified convergence rate calculation for salt grit backfilled caverns in rock salt

International Nuclear Information System (INIS)

Navarro, Martin

2013-03-01

Within the research and development project 3609R03210 of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, different methods were investigated, which are used for the simplified calculation of convergence rates for mining cavities in salt rock that have been backfilled with crushed salt. The work concentrates on the approach of Stelte and on further developments based on this approach. The work focuses on the physical background of the approaches. Model specific limitations are discussed and possibilities for further development are pointed out. Further on, an alternative approach is presented, which implements independent material laws for the convergence of the mining cavity and the compaction of the crushed salt backfill.

Glucuronoyl esterase--novel carbohydrate esterase produced by Schizophyllum commune.

Science.gov (United States)

Spániková, Silvia; Biely, Peter

2006-08-21

The cellulolytic system of the wood-rotting fungus Schizophyllum commune contains an esterase that hydrolyzes methyl ester of 4-O-methyl-d-glucuronic acid. The enzyme, called glucuronoyl esterase, was purified to electrophoretic homogeneity from a cellulose-spent culture fluid. Its substrate specificity was examined on a number of substrates of other carbohydrate esterases such as acetylxylan esterase, feruloyl esterase and pectin methylesterase. The glucuronoyl esterase attacks exclusively the esters of MeGlcA. The methyl ester of free or glycosidically linked MeGlcA was not hydrolysed by other carbohydrate esterases. The results suggest that we have discovered a new type of carbohydrate esterase that might be involved in disruption of ester linkages connecting hemicellulose and lignin in plant cell walls.

Design and Development of Mixed Film of Pectin: Ethyl Cellulose for Colon Specific Drug Delivery of Sennosides and Triphala

Science.gov (United States)

Momin, Munira; Pundarikakshudu, K.; Nagori, S. A.

2008-01-01

The present study was aimed at developing colon specific drug delivery system for sennosides and Triphala. These drugs are reputed Ayurvedic medicines for constipation in India. The proposed device explored the application of pectin and ethyl cellulose as a mixed film for colon specific delivery. This mixed film was prepared using non-aqueous solvents like acetone and isopropyl alcohol. A 32 factorial design was adopted to optimize the formulation variables like, ratio of ethyl cellulose to pectin (X1) and coat weight (X2). The rate and extent of drug release were found to be related to the thickness and the ratio of pectin to ethyl cellulose within the film. Statistical treatments to the drug release data revealed that the X1 variable was more important than X2. Under simulated colonic conditions, drug release was more pronounced from coating formulations containing higher proportions of pectin. The surface of the device was coated with Eudragit S100 to ensure that the device was more pH dependent and trigger the drug release only at higher pH. The final product is expected to have the advantage of being biodegradable and pH dependant. This type of a film effectively releases the drug while maintaining its integrity. PMID:20046742

Electrophoretic Ink Display Prepared by Jelly Fig Pectin/Gelatin Microspheres

Directory of Open Access Journals (Sweden)

Wing-Ming Chou

2015-05-01

Full Text Available A brand new Bio-Electronic ink (Bio-E ink display device was prepared and characterized in this study. Semiconductor material, copper phthalocyanine (CuPc was modified by cationic surfactants, cetylpyridinium chloride (CPC, as the core material, and the shell of capsule was prepared by jelly fig pectin, gelatin and sodium dodecyl sulphate (SDS. Here, jelly fig pectin was provided as the shell material for the first time. Chemical structure of the modified CuPc was characterized by Fourier Transform Infrared Spectrometer (FTIR. The core-shell microcapsules were achieved by coacervation method in an oil/water (O/W emulsion system. The particle size and morphology of microcapsules were affected by the concentrations of SDS and pH values of the O/W emulsion system. A new microcapsule-based electrophoretic display device was presented. Its image display ability of the microcapsules electrophoretic device was presented as appropriated electric power was applied, and the response time was 0.06 sec under 0.1 V/mm of electric field. Moreover, we found that its image contrast ratio of display device was influenced by the particle sizes of the microcapsules.

Swelling and Degradation of Calcium-Pectic Gel Particles Made of Pectins of Silene vulgaris and Lemna minor Сallus Cultures at Different Concentrations of Pectinase in an Artificial Colon Environment

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Anatoly A. Shubakov

2018-03-01

Full Text Available Spherical calcium-pectic gel particles (CaPGPs were obtained from pectins of callus cultures (CC of campion Silene vulgaris (silenan and duckweed Lemna minor (lemnan, as well as from commercial apple and citrus pectins by the method of ionotropic gelation. We studied the morphological characteristics of the obtained gel particles and found that the largest gel particles were formed from citrus pectin (CP, and the densest gel particles were formed from lemnan pectin (LP. The swelling and degradation of CaPGPs were comparatively evaluated by incubation in a simulated gastrointestinal environment. The swelling and degradation of CaPGPs formed from pectins of the silenan and lemnan callus cultures were studied at different concentrations of pectinase (0.4, 0.8 and 1.7 mg/ml in the simulated fluid of the colon. It has been established that the CaPGPs obtained from lemnan are more resistant to degradation in the simulated colon fluid than CaPGP obtained from silenan. It was shown that the concentration of pectinase in the simulated fluid of the colon and the type of pectin affect the degradability of CaPGPs formed on the basis of pectins of callus cultures.

Pectins from apple pomace - characterization by 13C and 1H NMR spectroscopy

International Nuclear Information System (INIS)

Marcon, M.V.; Carneiro, P.I.B.; Wosiacki, G.; Beleski-Carneiro, E.; Petkowicz, C.L.O.

2005-01-01

Pectins were extracted from apple pomace flour with 5% (w/v) aqueous citric acid solutions under different time and temperature according to an experimental design (factorial 2 2 with triplicate of central point). Monosaccharide composition of fractions was determined by colorimetric analysis and gas chromatography. The structure of pectins was studied by NMR spectroscopy. The degree of esterification (DE=30.5-55.9), determined by FT-IR spectroscopy, was indirectly correlated with increasing temperature and time of extraction, showing that drastic conditions for extraction promote hydrolysis of esterified units. High content of galacturonic acid is consistent with the smooth region of the polysaccharide. 13 C and 1 H NMR spectroscopy confirmed the presence of uronic acids in the free and methyl ester forms. NMR data also showed the presence of arabinan and galactan as side chains. (author)

Post harvest changes gamma-irradiated banana Prata

International Nuclear Information System (INIS)

Vilas Boas, E.V. de; Chitarra, A.B.; Chitarra, M.I.F.

1996-01-01

The effect of the gamma-irradiation was evaluated at 0.25 and 0.50 kGy, on the development of peel coloration, CO 2 and ethylene evolution, conversion of starch to sugars, pulp-to-peel ratio, pectic solubilization and activities of enzymes of the cell wall, pectin methylesterase (PME), and polygalacturonase (PG), during maturation of 'Prata' bananas. The gamma-irradiation did not affect the normal colour development of the fruits. An increase in the ethylene peak and a decrease in the CO 2 peak was observed. The gamma-irradiation did not affect the degradation of starch, while a delay in soluble sugar accumulation was noted on the 6 and 7 colour grades. The fruits subjected to 0.25 kGy had the highest increase in the pulp-to-peel relation, beginning with colour grade 5, due to a possible stress effect of that dose. An increase of pectin solubilization was observed. Higher PME activities were exhibited by irradiated fruits, although the gamma-irradiation suppressed the PG activity throughout the maturation period. The gamma-irradiation did not extend the post-harvest life of 'Prata' bananas. (author) [pt

Pectinmethylesterases (PME and pectinmethylesterase inhibitors (PMEI enriched during phloem fiber development in flax (Linum usitatissimum.

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David Pinzon-Latorre

Full Text Available Flax phloem fibers achieve their length by intrusive-diffusive growth, which requires them to penetrate the extracellular matrix of adjacent cells. Fiber elongation therefore involves extensive remodelling of cell walls and middle lamellae, including modifying the degree and pattern of methylesterification of galacturonic acid (GalA residues of pectin. Pectin methylesterases (PME are important enzymes for fiber elongation as they mediate the demethylesterification of GalA in muro, in either a block-wise fashion or in a random fashion. Our objective was to identify PMEs and PMEIs that mediate phloem fiber elongation in flax. For this purpose, we measured transcript abundance of candidate genes at nine different stages of stem and fiber development and found sets of genes enriched during fiber elongation and maturation as well as during xylem development. We expressed one of the flax PMEIs in E. coli and demonstrated that it was able to inhibit most of the native PME activity in the upper portion of the flax stem. These results identify key genetic components of the intrusive growth process and define targets for fiber engineering and crop improvement.

PARVUS affects aluminium sensitivity by modulating the structure of glucuronoxylan in Arabidopsis thaliana.

Science.gov (United States)

Zhu, Xiao Fang; Wan, Jiang Xue; Wu, Qi; Zhao, Xu Sheng; Zheng, Shao Jian; Shen, Ren Fang

2017-09-01

Glucuronoxylan (GX), an important component of hemicellulose in the cell wall, appears to affect aluminium (Al) sensitivity in plants. To investigate the role of GX in cell-wall-localized xylan, we examined the Arabidopsis thaliana parvus mutant in detail. This mutant lacks α-D-glucuronic acid (GlcA) side chains in GX and has greater resistance to Al stress than wild-type (WT) plants. The parvus mutant accumulated lower levels of Al in its roots and cell walls than WT despite having cell wall pectin content and pectin methylesterase (PME) activity similar to those of WT. Our results suggest that the altered properties of hemicellulose in the mutant contribute to its decreased Al accumulation. Although we observed almost no differences in hemicellulose content between parvus and WT under control conditions, less Al was retained in parvus hemicellulose than in WT. This observation is consistent with the finding that GlcA substitutions in WT GX, but not mutant GX, were increased under Al stress. Taken together, these results suggest that the modulation of GlcA levels in GX affects Al resistance by influencing the Al binding capacity of the root cell wall in Arabidopsis. © 2017 John Wiley & Sons Ltd.

Assembly and enlargement of the primary cell wall in plants

Science.gov (United States)

Cosgrove, D. J.

1997-01-01

Growing plant cells are shaped by an extensible wall that is a complex amalgam of cellulose microfibrils bonded noncovalently to a matrix of hemicelluloses, pectins, and structural proteins. Cellulose is synthesized by complexes in the plasma membrane and is extruded as a self-assembling microfibril, whereas the matrix polymers are secreted by the Golgi apparatus and become integrated into the wall network by poorly understood mechanisms. The growing wall is under high tensile stress from cell turgor and is able to enlarge by a combination of stress relaxation and polymer creep. A pH-dependent mechanism of wall loosening, known as acid growth, is characteristic of growing walls and is mediated by a group of unusual wall proteins called expansins. Expansins appear to disrupt the noncovalent bonding of matrix hemicelluloses to the microfibril, thereby allowing the wall to yield to the mechanical forces generated by cell turgor. Other wall enzymes, such as (1-->4) beta-glucanases and pectinases, may make the wall more responsive to expansin-mediated wall creep whereas pectin methylesterases and peroxidases may alter the wall so as to make it resistant to expansin-mediated creep.

Modified pectin from Theobroma cacao induces potent pro-inflammatory activity in murine peritoneal macrophage.

Science.gov (United States)

Amorim, Juliana C; Vriesmann, Lucia Cristina; Petkowicz, Carmen L O; Martinez, Glaucia Regina; Noleto, Guilhermina R

2016-11-01

In vitro effects of acetylated pectin (OP) isolated from cacao pod husks (Theobroma cacao L.), its partially deacetylated and de-esterified form (MOP), and a commercial homogalacturonan (PG) were investigated on murine peritoneal macrophages. MOP stood out among the studied pectins. After 48h of incubation, compared with the control group, it was able to promote significant macrophage morphological differentiation from resident to activated stage and also stimulated nitric oxide production, which reached a level of 85% of that of LPS stimulus. In the presence of the highest tested concentration of MOP (200μg·mL -1 ), the levels of the cytokines TNF-α (6h) and IL-12 and IL-10 (48h) increased substantially in relation to untreated cells. Our results show that the partial deacetylation and de-esterification of pectin extracted from cacao pod husks (T. cacao L.) produced a polymer with greater ability than its native form to activate macrophages to a cytotoxic phenotype. Like this, they provide the possibility of a therapeutic application to MOP, which could lead to a decreased susceptibility to microbial infection besides antitumor activity. Additionally, the present results also corroborate with the proposition of that the chemical modifications of the biopolymers can result in an improved molecule with new possibilities of application. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of ca2+ to salicylic acid release in pectin based controlled drug delivery system

Science.gov (United States)

Kistriyani, L.; Wirawan, S. K.; Sediawan, W. B.

2016-01-01

Wastes from orange peel are potentially be utilized to produce pectin, which are currently an import commodity. Pectin can be used in making edible film. Edible films are potentially used as a drug delivery system membrane after a tooth extraction. Drug which is used in the drug delivery system is salicylic acid. It is an antiseptic. In order to control the drug release rate, crosslinking process is added in the manufacturing of membrane with CaCl2.2H2O as crosslinker. Pectin was diluted in water and mixed with a plasticizer and CaCl2.2H2O solution at 66°C to make edible film. Then the mixture was dried in an oven at 50 °C. After edible film was formed, it was coated using plasticizer and CaCl2.2H2O solution with various concentration 0, 0.015, 0.03 and 0.05g/mL. This study showed that the more concentration of crosslinker added, the slower release of salicylic acid would be. This was indicated by the value of diffusivites were getting smaller respectively. The addition of crosslinker also caused smaller gels swelling value,which made the membrane is mechanically stronger

Evaluation of the use of pectin among children living on the territories contaminated by cesium. Situation and critical analysis of publications; Evaluation de l'emploi de la pectine chez les enfants vivant sur les territoires contamines par le cesium. Etat de l'art et analyse critique des publications

Energy Technology Data Exchange (ETDEWEB)

Jourdain, J.R.; Dublineau, I.; Phan, G

2005-07-01

This report includes four parts. The first one gives the situation of knowledge on the biological effects of pectin in human nutrition and in case of exposure to heavy metals. The second part presents an analysis of publications devoted to biological effects of pectins in case of chronic intake of radioisotopes.The third part is a synthesis that gives the principal teaching of this analysis. The last part presents the propositions of I.R.S.N relative to future works and studies that it would be interesting to launch in order to complete the knowledge relative to the use of pectin in the case of chronic intake of radioisotopes. (N.C.)

Pectin and the role of the physical properties of the cell wall in pollen tube growth of Solanum chacoense.

Science.gov (United States)

Parre, Elodie; Geitmann, Anja

2005-02-01

The cell wall is one of the structural key players regulating pollen tube growth, since plant cell expansion depends on an interplay between intracellular driving forces and the controlled yielding of the cell wall. Pectin is the main cell wall component at the growing pollen tube apex. We therefore assessed its role in pollen tube growth and cytomechanics using the enzymes pectinase and pectin methyl esterase (PME). Pectinase activity was able to stimulate pollen germination and tube growth at moderate concentrations whereas higher concentrations caused apical swelling or bursting in Solanum chacoense Bitt. pollen tubes. This is consistent with a modification of the physical properties of the cell wall affecting its extensibility and thus the growth rate, as well as its capacity to withstand turgor. To prove that the enzyme-induced effects were due to the altered cell wall mechanics, we subjected pollen tubes to micro-indentation experiments. We observed that cellular stiffness was reduced and visco-elasticity increased in the presence of pectinase. These are the first mechanical data that confirm the influence of the amount of pectins in the pollen tube cell wall on the physical parameters characterizing overall cellular architecture. Cytomechanical data were also obtained to analyze the role of the degree of pectin methyl-esterification, which is known to exhibit a gradient along the pollen tube axis. This feature has frequently been suggested to result in a gradient of the physical properties characterizing the cell wall and our data provide, for the first time, mechanical support for this concept. The gradient in cell wall composition from apical esterified to distal de-esterified pectins seems to be correlated with an increase in the degree of cell wall rigidity and a decrease of visco-elasticity. Our mechanical approach provides new insights concerning the mechanics of pollen tube growth and the architecture of living plant cells.

Combinatorial efficacy of Trichoderma spp. and Pseudomonas fluorescens to enhance suppression of cell wall degrading enzymes produced by Fusarium wilt of Arachis hypogaea.L

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P Rajeswari

2017-12-01

Full Text Available Fusarium oxysporum, the soil borne pathogen causes vascular wilt, on majority of crop plants. It has been demonstrated that two different species of Trichoderma and Pseudomonas fluorescens suppress disease by different mechanisms. Therefore, application of a mixture of these biocontrol agents, and thus of several suppressive mechanisms, may represent a viable control strategy. A necessity for biocontrol by combinations of biocontrol agents can be the compatibility of the co-inoculated micro-organisms. Hence, compatibility between Trichoderma spp. and Pseudomonas fluorescens that have the ability to suppress Fusarium oxysporum in vitro on the activity of pectinolytic enzymes of Fusarium oxysporum. The activity of pectinolytic enzymes, i.e. pectin methyl esterase, endo and exo polymethylgalacturonases and exo and endo pectin trans eliminases produced by Fusarium oxysporum (Control was higher. Maximum inhibition of pectin methylesterase, exo and endo polymethylgalacturonase and exo and endopectin trans eliminase was shown by culture filtrate of Trichoderma viride + Pseudomonas fluorescens (Tv+Pf (1+2%, followed by Trichoderma harzianum + Pseudomonas fluorescens, (Th +Pf (1.5+2% and Trichoderma viride + Trichoderma harzianum (Tv+Th (1+1.5%. However, pathogenecity suppression of Fusarium oxysporum, a causative of Arachis hypogaea. L by the compatible combination of Trichodema viride + Pseudomonas fluorescens (1+2% was significantly better as compared to the single bio-agent. This indicates that specific interactions between biocontrol agents influence suppression of pathogenicity factors directly by combinations of these compatible bio-agents.

Comparative studies on conventional (water-hot acid) and non-conventional (ultrasonication) procedures for extraction and chemical characterization of pectin from peel waste of mango cultivar chaunsa

International Nuclear Information System (INIS)

Kausar, S.; Saeed, A.

2015-01-01

Pectin, a naturally occurring heteropolysaccharide, is widely used as a functional ingredient in food and pharmaceutical industries due to its gelling and stabilizing properties. During the present study pectin was extracted from peel of mango (cultivar Chaunsa) using conventional (water-hot acid) and non-conventional (ultrasonication) methods. In conventional method, HNO/sub 3/, H/sub 2/SO/sub 4/, or HCl was used under variable conditions of pH (2.0, 2.5, 3.0), temperature (70, 80, 90, 100 degree C), duration of extraction (30, 60, 90, 120 min), and solvents (ethanol, methanol, acetone, isopropyl alcohol). Maximum yield of 16.6 g pectin 100 g/sup -1/ peel was obtained with HNO/sub 3/ at pH 2.5, 90 degree C, 90 min extraction, and ethanol. Whereas in non-conventional method, ultrasonication was used for different time intervals (10, 20, 40 min) using HNO/sub 3/ at pH 2.5 and 90 degree C. Maximum yield of 15.8 g pectin 100 g/sup -1/ peel was obtained by this method in 20 min. Pectin extracted by the above two methods was found to be of high quality as was determined in respect of methoxyl and galacturonic acid contents, degree of esterification, equivalent weight, and FTIR spectra. Extraction of pectin from mango peel by employing non-conventional method (ultrasonication) was observed to be an energy efficient method due to its less extraction time (20 min as compared to 90 min in conventional method) suggesting its suitability on commercial scale for the extraction of pectin from mango and other available fruit peel wastes. (author)

Analysis of different de-esterification mechanisms for pectin by enzymatic fingerprinting using endopectin lyase and endopolygalacturonase II from A. niger

DEFF Research Database (Denmark)

Limberg, G; Körner, R; Buchholt, H C

2000-01-01

with either endopectin lyase (PL) or endopolygalacturonase II (PG II) from Aspergillus niger were analysed using matrix assisted laser desorption ionisation mass spectrometry (MALDIMS) and high-performance anion-exchange chromatography with pulsed amperometric or UV detection (HPAEC-PAD/UV). Time course......A series of pectins with different distribution patterns of methyl ester groups was produced by treatment with either plant (p-PME) or fungal pectin methyl esterases (f-PME) and compared with those obtained by base catalysed de-esterification. The products generated by digestion of these pectins...... analysis using MALDIMS was used to identify the most preferred substrate for each enzyme. For PL, this was shown to be fully methyl esterified HG whereas for PG II, long regions of HG without any methyl esterification, as produced by p-PME was the optimal substrate. The blockwise de-esterification caused...

Effects of apples and specific apple components on the cecal environment of conventional rats: role of apple pectin

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Markowski Jaroslaw

2010-01-01

Full Text Available Abstract Background Our study was part of the large European project ISAFRUIT aiming to reveal the biological explanations for the epidemiologically well-established health effects of fruits. The objective was to identify effects of apple and apple product consumption on the composition of the cecal microbial community in rats, as well as on a number of cecal parameters, which may be influenced by a changed microbiota. Results Principal Component Analysis (PCA of cecal microbiota profiles obtained by PCR-DGGE targeting bacterial 16S rRNA genes showed an effect of whole apples in a long-term feeding study (14 weeks, while no effects of apple juice, purée or pomace on microbial composition in cecum were observed. Administration of either 0.33 or 3.3% apple pectin in the diet resulted in considerable changes in the DGGE profiles. A 2-fold increase in the activity of beta-glucuronidase was observed in animals fed with pectin (7% in the diet for four weeks, as compared to control animals (P Bacteroidetes, whereas bands that became more prominent represented mainly Gram-positive anaerobic rods belonging to the phylum Firmicutes, and specific species belonging to the Clostridium Cluster XIVa. Quantitative real-time PCR confirmed a lower amount of given Bacteroidetes species in the pectin-fed rats as well as in the apple-fed rats in the four-week study (P Clostridium coccoides (belonging to Cluster XIVa, as well as of genes encoding butyryl-coenzyme A CoA transferase, which is involved in butyrate production, was detected by quantitative PCR in fecal samples from the pectin-fed animals. Conclusions Our findings show that consumption of apple pectin (7% in the diet increases the population of butyrate- and β-glucuronidase producing Clostridiales, and decreases the population of specific species within the Bacteroidetes group in the rat gut. Similar changes were not caused by consumption of whole apples, apple juice, purée or pomace.

Accumulation of metal ions by pectinates

Science.gov (United States)

Deiana, S.; Deiana, L.; Palma, A.; Premoli, A.; Senette, C.

2009-04-01

The knowledge of the mechanisms which regulate the interactions of metal ions with partially methyl esterified linear polymers of α-1,4 linked D-galacturonic acid units (pectinates), well represented in the root inner and outer apoplasm, is of great relevance to understand the processes which control their accumulation at the soil-root interface as well as their mobilization by plant metabolites. Accumulation of a metal by pectinates can be affected by the presence of other metals so that competition or distribution could be expected depending on the similar or different affinity of the metal ions towards the binding sites, mainly represented by the carboxylate groups. In order to better understand the mechanism of accumulation in the apoplasm of several metal ions, the sorption of Cd(II), Zn(II), Cu(II), Pb(II) and Cr(III) by a Ca-polygalacturonate gel, used as model of the soil-root interface, with a degree of esterification of 18% (PGAE1) and 65% (PGAE2) was studied at pH 3.0, 4.0, 5.0 and 6.0 in the presence of CaCl2 2.5 mM.. The results show that sorption increases with increasing both the initial metal concentration and pH. A similar sorption trend was evidenced for Cu(II) and Pb(II) and for Zn(II) and Cd(II), indicating that the mechanism of sorption for these two ionic couples is quite different. As an example, at pH 6.0 and an initial metal concentration equal to 2.0 mM, the amount of Cu(II) and Pb(II) sorbed was about 1.98 mg-1 of PGAE1 while that of Cd(II) and Zn(II) was about 1.2 mg-1. Cr(III) showed a rather different sorption trend and a much higher amount (2.8 mg-1of PGAE1 at pH 6.0) was recorded. The higher affinity of Cr(III) for the polysaccharidic matrix is attributable to the formation of Cr(III) polynuclear species in solution, as shown by the distribution diagrams obtained through the MEDUSA software. On the basis of these findings, the following affinity towards the PGAE1 can be assessed: Cr(III) > Cu(II) ? Pb(II) > Zn (II) ? Cd

Optimisation and In Vivo Evaluation of Pectin Based Drug Delivery System Containing Curcumin for Colon

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Kishor Butte

2014-01-01

Full Text Available The higher incidences of side effects of existing drugs have shifted researchers and clinicians to explore the dietary phytoconstituents for its therapeutic potentials. The present study is based on compression coated curcumin tablet for the colon. Curcumin has anti-inflammatory and antioxidant properties. Curcumin presents a bioavailability problem due to poor solubility. An inclusion complex was formed with hydroxypropyl-β-cyclodextrin to enhance the solubility. In this study, the core tablet of curcumin inclusion complex was compressed between the layers of polymer blend of pectin and Eudragit S100. The 32 full factorial design was utilised for optimization of the formulation. The polymer ratio (X1 and coat thickness (X2 presented significant effects on the selected responses, i.e., percent drug release after 4 hours (Y240 and difference in percent drug release between 4th and 6th hour (Ydiff in presence of pectinase enzyme. The results revealed that higher coat weight (600 mg and higher level of pectin ratio (70% w/w protected the curcumin tablet till ascending colon. The in vivo studies by roentgenography method using human volunteers supported these observations. Hence, it can be concluded that the combination of pectin and Eudrgit S100 makes the system biodegradable and pH dependent for targeting the drug to the colon.

Pectin methyl esterase inhibits intrusive and symplastic cell growth in developing wood cells of Populus.

Science.gov (United States)

Siedlecka, Anna; Wiklund, Susanne; Péronne, Marie-Amélie; Micheli, Fabienne; Lesniewska, Joanna; Sethson, Ingmar; Edlund, Ulf; Richard, Luc; Sundberg, Björn; Mellerowicz, Ewa J

2008-02-01

Wood cells, unlike most other cells in plants, grow by a unique combination of intrusive and symplastic growth. Fibers grow in diameter by diffuse symplastic growth, but they elongate solely by intrusive apical growth penetrating the pectin-rich middle lamella that cements neighboring cells together. In contrast, vessel elements grow in diameter by a combination of intrusive and symplastic growth. We demonstrate that an abundant pectin methyl esterase (PME; EC 3.1.1.11) from wood-forming tissues of hybrid aspen (Populus tremula x tremuloides) acts as a negative regulator of both symplastic and intrusive growth of developing wood cells. When PttPME1 expression was up- and down-regulated in transgenic aspen trees, the PME activity in wood-forming tissues was correspondingly altered. PME removes methyl ester groups from homogalacturonan (HG) and transgenic trees had modified HG methylesterification patterns, as demonstrated by two-dimensional nuclear magnetic resonance and immunostaining using PAM1 and LM7 antibodies. In situ distributions of PAM1 and LM7 epitopes revealed changes in pectin methylesterification in transgenic trees that were specifically localized in expanding wood cells. The results show that en block deesterification of HG by PttPME1 inhibits both symplastic growth and intrusive growth. PttPME1 is therefore involved in mechanisms determining fiber width and length in the wood of aspen trees.

Enhancement of Moisture Protective Properties and Stability of Pectin through Formation of a Composite Film: Effects of Shellac and Plasticizer.

Science.gov (United States)

Luangtana-Anan, Manee; Soradech, Sitthiphong; Saengsod, Suthep; Nunthanid, Jurairat; Limmatvapirat, Sontaya

2017-12-01

The aim of this investigation was to develop the high moisture protective ability and stable pectin through the design of composite films based on varying shellac concentrations. A film casting method was applied to prepare a free film. The moisture protective properties and mechanical properties were investigated. The findings was the composite films exhibited the reductions in the hydrophilicity, water vapor permeability, and the moisture content compared with pectin films. The single and composite films were then study for their stability at 40 °C and 75% RH for 90 d. Among the concentrations of shellac, 50% (w/w) could improve stability in terms of moisture protection after 90 d of storage, whereas lower concentrations of shellac (10% to 40%) could not achieve this. However, the higher shellac content also contributed to weaker mechanical properties. The mechanical improvement and stability of composite films with the incorporation of plasticizers were further investigated. Polyethylene glycol 400 and diethyl phthalate at a concentration of 10% were used. The results indicated that both plasticizers could enhance the mechanical characteristics and had a slight effect on moisture protection. The stability of pectin in terms of moisture protective properties could, therefore, be modified through the fabrication of composite films with hydrophobic polymers, that is, shellac and the addition of proper plasticizers to enhance mechanical properties, which could offer wide applications for edible film in food, agro, and pharmaceutical industries. The composite film with 50% shellac could improve moisture protective properties of pectin film. Adding a plasticizer could build up the higher mechanical characteristics of composite film. Stability of pectin could be modified by fabrication of composite films with proper content of shellac and plasticizer. © 2017 Institute of Food Technologists®.

Edible Film from the Pectin of Papaya Skin (The Study of Cassava Starch and Glycerol Addition)

Science.gov (United States)

Rosida; Sudaryati; Yahya, A. M.

2018-01-01

The production of edible cooking made from the pectin of papaya skin with cassava starch and glycerol adition had been studied. The usage of pectin of papaya skin was one way to use papaya skin waste in order to raise its economic value. The aim of this study was to study the effect of cassava starch and glycerol concentration on the product qualities and to determine the the best treatment in making a good quality adible film and acceptable by the consumer. This research used completely randomized design in factorial patern with two factors. The first factor was cassava starch concentration (25%, 35% and 45%) and the second factor was glycerol concentration (20 %, 15% and 10). The data were analyzed by Analysis of Variance (Anova) and Duncan’s Multiple Range Test to detect the difference between the treatment. The best treatment was 25% cassava starch addition and 10% glycerol concentration which produced edible film which had moisture content of 21.16%, thickness of 0.023 mm, tensile strength of 1.900 N, elasticity of 14.223%, and vapor transmission rate of 116.963 g/m2/24 hours. So the production of edible film from papaya skin pectin was potential to be developed.

High-pressure processing of apple juice: kinetics of pectin methyl esterase inactivation.

Science.gov (United States)

Riahi, Esmaeil; Ramaswamy, Hosahalli S

2003-01-01

High-pressure (HP) inactivation kinetics of pectin methyl esterase (PME) in apple juice were evaluated. Commercial PME was dispensed in clarified apple juice, sealed in dual peel sterilizable plastic bags, and subjected to different high-pressure processing conditions (200-400 MPa, 0-180 min). Residual enzyme activity was determined by a titration method estimating the rate of free carboxyl group released by the enzyme acting on pectin substrate at pH 7.5 (30 degrees C). The effects of pressure level and pressure holding time on enzyme inactivation were significant (p < 0.05). PME from the microbial source was found to be more resistant (p < 0.05) to pressure inactivation than PME from the orange peel. Almost a full decimal reduction in the activity of commercial PME was achieved by HP treatment at 400 MPa for 25 min. Inactivation kinetics were evaluated on the basis of a dual effect model involving a pressure pulse effect and a first-order rate model, and the pressure sensitivity of rate constants was modeled by using the z-value concept.

Extração de pectina de goiaba desidratada Extraction of pectin from dehydrated guava

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Cláudia Leite Munhoz

2010-03-01

Full Text Available Goiabas (Psidium guajava L. cultivar Pedro Sato foram utilizadas para extração de pectina. Os frutos separados polpa e polpa com casca foram secos em estufa com circulação de ar. Amostras secas foram caracterizadas física e quimicamente. O planejamento composto central rotacional com quatro pontos axiais e três repetições no ponto central foi utilizado para determinar o rendimento de extração de pectina das farinhas de polpa e de polpa com casca de goiaba. A extração foi realizada em 4 g de farinha para 200 mL de solução de ácido cítrico em diferentes concentrações e em diferentes tempos de extração, a temperatura de 97 ºC. As pectinas obtidas nas melhores condições de extração foram caracterizadas. A extração de pectina com ácido cítrico e precipitação alcoólica forneceu rendimentos acima de 11% para a farinha de polpa e de polpa com casca de goiaba. As melhores condições de extração foram: concentração de ácido cítrico de 5 g.100 g-1 e tempo de extração de 60 minutos. As pectinas obtidas apresentaram-se de baixa esterificação e com teor de ácido galacturônico próximo ao padrão comercial (65%.Pedro Sato cultivar guavas (Psidium guajava L. were used for extraction of pectin. The fruits were divided into pulp and pulp with peel, and dried in a stove with air circulation. Dry samples were characterized physically and chemically. The planning consisted of central axial rotation with four points, and three replicates in the central point were used to determine the extraction yield of pectin flour from the guava pulp and pulp with peel. The extraction was performed in 4 g of flour to 200 mL of solution of citric acid at different concentrations and at different times of extraction, at a temperature of 97 ºC. The pectins obtained in optimum conditions for extraction were characterized. The extraction of pectin with citric acid and alcohol precipitation provided yield above 11% for the guava flour, with

Homogalacturonan methyl-esterification and plant development.

Science.gov (United States)

Wolf, Sebastian; Mouille, Grégory; Pelloux, Jérome

2009-09-01

The ability of a plant cell to expand is largely defined by the physical constraints imposed by its cell wall. Accordingly, cell wall properties have to be regulated during development. The pectic polysaccharide homogalacturonan is a major component of the plant primary walls. Biosynthesis and in muro modification of homogalacturonan have recently emerged as key determinants of plant development, controlling cell adhesion, organ development, and phyllotactic patterning. This review will focus on recent findings regarding impact of homogalacturonan content and methyl-esterification status of this polymer on plant life. De-methyl-esterification of homogalacturonan occurs through the action of the ubiquitous enzyme 'pectin methyl-esterase'. We here describe various strategies developed by the plant to finely tune the methyl-esterification status of homogalacturonan along key events of the plant lifecycle.

Pectin-honey coating as novel dehydrating bioactive agent for cut fruit: Enhancement of the functional properties of coated dried fruits.

Science.gov (United States)

Santagata, Gabriella; Mallardo, Salvatore; Fasulo, Gabriella; Lavermicocca, Paola; Valerio, Francesca; Di Biase, Mariaelena; Di Stasio, Michele; Malinconico, Mario; Volpe, Maria Grazia

2018-08-30

In this paper, a novel and sustainable process for the fruit dehydration was described. Specifically, edible coatings based on pectin and honey were prepared and used as dehydrating and antimicrobial agents of cut fruit samples, in this way promoting the fruit preservation from irreversible deteriorative processes. Pectin-honey coating was tested on apple, cantaloupe melon, mango and pineapple. The analysis were performed also on uncoated dehydrated fruits (control). The coated fruit evidenced enhanced dehydration percentage, enriched polyphenol and vitamin C contents, improved antioxidant activity and volatile molecules profile. Moreover, the antimicrobial activity against Pseudomonas and Escherichia coli was assessed. Finally, morphological analysis performed on fruit fractured surface, highlighted the formation of a non-sticky and homogeneous thin layer. These outcomes suggested that the novel fruit dehydration process, performed by using pectin-honey coating, was able to both preserve the safety and quality of dehydrated fruits, and enhance their authenticity and naturalness. Copyright © 2018 Elsevier Ltd. All rights reserved.

SALT4: a two-dimensional displacement discontinuity code for thermomechanical analysis in bedded salt deposits

International Nuclear Information System (INIS)

1983-04-01

SALT4 is a two-dimensional analytical/displacement-discontinuity code designed to evaluate temperatures, deformation, and stresses associated with underground disposal of radioactive waste in bedded salt. This code was developed by the University of Minnesota. This documentation describes the mathematical equations of the physical system being modeled, the numerical techniques utilized, and the organization of the computer code, SALT4. The SALT4 code takes into account: (1) viscoelastic behavior in the pillars adjacent to excavations; (2) transversely isotropic elastic moduli such as those exhibited by bedded or stratified rock; and (2) excavation sequence. Major advantages of the SALT4 code are: (1) computational efficiency; (2) the small amount of input data required; and (3) a creep law consistent with laboratory experimental data for salt. The main disadvantage is that some of the assumptions in the formulation of SALT4, i.e., temperature-independent material properties, render it unsuitable for canister-scale analysis or analysis of lateral deformation of the pillars. The SALT4 code can be used for parameter sensitivity analyses of two-dimensional, repository-scale, thermal and thermomechanical response in bedded salt during the excavation, operational, and post-closure phases. It is especially useful in evaluating alternative patterns and sequences of excavation or waste canister placement. SALT4 can also be used to verify fully numerical codes. This is similar to the use of analytic solutions for code verification. Although SALT4 was designed for analysis of bedded salt, it is also applicable to crystalline rock if the creep calculation is suppressed. In Section 1.5 of this document the code custodianship and control is described along with the status of verification, validation and peer review of this report

Isolation and Expression analysis of OsPME1, encoding for a putative Pectin Methyl Esterase from Oryza sativa (subsp. indica)

OpenAIRE

Kanneganti, Vydehi; Gupta, Aditya Kumar

2009-01-01

Pectin Methyl Esterases (PMEs) play an essential role during plant development by affecting the mechanical properties of the plant cell walls. Recent studies indicated that PMEs play important role in pollen tube development. In this study, we isolated a 1.3 kb cDNA clone from rice panicle cDNA library. It contained a 1038 bp of open reading frame (ORF) encoding for a putative pectin methyl esterase of 345 aminoacids with a 20 aminoacid signal peptide and was hence designated as OsPME1 (Oryza...

Improvement of Probiotic Survival in Fruit juice and under Gastrointestinal conditions using Pectin-Nanochitin-Nanolignocellulose as a Novel Prebiotic Gastrointestinal-Resistant Matrix

Directory of Open Access Journals (Sweden)

Alireza Chackoshian Khorasani

2017-08-01

Full Text Available Background and Objective: Increasing survivability of probiotics in low pH juices and in gastrointestinal conditions is important for probiotic food industry. Nanofibers can reinforce the structure of entrapment matrices protecting probiotics in harsh conditions. This study investigated pectin-based bionanocomposites improved with nanochitin, nanolignocellulose and bacterial nanocellulose to introduce a prebiotic gastrointestinal-resistant matrix for enhancing the survival of Bacillus coagulans as a probiotic.Material and Methods: The bionanocomposites with various compositions were designed using mixture design method. These were fabricated based on cross-linking of calcium ions with pectin for entrapment of Bacillus coagulans. The survivability of probiotic was evaluated at 4°C or 25°C over a 5-week storage in peach juice and under simulated gastrointestinal conditions.Results and Conclusion: The prebiotic score of the pectin-nanochitin-nanolignocellulose (50:25:25% w w-1 was determined as 1.36. The survivability of Bacillus coagulans entrapped within the pectin-nanochitin-nanolignocellulose matrix was ~65% under gastrointestinal treatment. The surface structure of the matrix was relatively smooth coherent, compact and wrinkled due to the three-dimensional arrangement of the nanofibers of chitin and lignocellulose incorporated within pectin. The highest survivability of the entrapped bacteria was ~68% compared to the survivability of the free cell (~53% at the end of 5-week storage period. After 21 day storage in the juice, the survivability of the entrapped bacteria treated under sequential digestion was ~58% as compared to that of the free cell (~43%. The present findings proposed a promising prebiotic matrix to protect probiotics in low pH fruit juice and the gastrointestinal tract.Conflict of interest: The authors declare no conflict of interest.

Bioactive Films Containing Alginate-Pectin Composite Microbeads with Lactococcus lactis subsp. lactis: Physicochemical Characterization and Antilisterial Activity

Directory of Open Access Journals (Sweden)

Mariam Bekhit

2018-02-01

Full Text Available Novel bioactive films were developed from the incorporation of Lactococcus lactis into polysaccharide films. Two different biopolymers were tested: cellulose derivative (hydroxylpropylmethylcellulose (HPMC and corn starch. Lactic acid bacteria (LAB free or previously encapsulated in alginate-pectin composite hydrogel microbeads were added directly to the film forming solution and films were obtained by casting. In order to study the impact of the incorporation of the protective culture into the biopolymer matrix, the water vapour permeability, oxygen permeability, optical and mechanical properties of the dry films were evaluated. Furthermore, the antimicrobial effect of bioactive films against Listeria monocytogenes was studied in synthetic medium. Results showed that the addition of LAB or alginate-pectin microbeads modified slightly films optical properties. In comparison with HPMC films, starch matrix proves to be more sensitive to the addition of bacterial cells or beads. Indeed, mechanical resistance of corn starch films was lower but barrier properties were improved, certainly related to the possible establishment of interactions between alginate-pectin beads and starch. HPMC and starch films containing encapsulated bioactive culture showed a complete inhibition of listerial growth during the first five days of storage at 5 °C and a reduction of 5 logs after 12 days.

Hydration patterns and salting effects in sodium chloride solution.

Science.gov (United States)

Li, Weifeng; Mu, Yuguang

2011-10-07

The salting effects of 2M sodium chloride electrolyte are studied based on a series of model solutes with properties ranging from hydrophobic to hydrophilic. Generally, hydrophobic solutes will be salted out and hydrophilic solutes will be salted in by NaCl solution. The solvation free energy changes are highly correlated with Kirkwood-Buff integrals. The underlying mechanism resorts to the preferential binding of ions and water to solutes. Our results demonstrate that the salting effect not only depends on the salt's position in Hofmeister series, but also on the solutes' specifics. Taking the hydration free energies of solutes and ions as independent variables, a schematic diagram of salting effects is suggested. The resolved multifaceted salting effects rely on the sensitive balance of the tripartite interaction among solutes, ions, and water. © 2011 American Institute of Physics

Feruloylated and Nonferuloylated Arabino-oligosaccharides from Sugar Beet Pectin Selectively Stimulate the Growth of Bifidobacterium spp. in Human Fecal in Vitro Fermentations

DEFF Research Database (Denmark)

Holck, Jesper; Lorentzen, Andrea; Vigsnæs, Louise Kristine

2011-01-01

The side chains of the rhamnogalacturonan I fraction in sugar beet pectin are particularly rich in arabinan moieties, which may be substituted with feruloyl groups. In this work the arabinan-rich fraction resulting from sugar beet pulp based pectin production was separated by Amberlite XAD...... feruloylated arabino-oligosaccharides from sugar beet pulp and an initial indication of the potentially larger bifidogenic effect of relatively long-chain arabino-oligosaccharides as opposed to short-chain arabino-oligosaccharides....

Safety evaluation of pectin-derived acidic oligosaccharides (pAOS): genotoxicity and sub-chronic studies.

NARCIS (Netherlands)

Garthoff, J.A.; Heemskerk, S.; Hempenius, R.A.; Lina, B.A.; Krul, C.A.; Koeman, J.H.; Speijers, G.J.

2010-01-01

Pectin-derived acidic oligosaccharides (pAOS) are non-digestible carbohydrates to be used in infant formulae and medical nutrition. To support its safety, the genotoxic potential of pAOS was evaluated. pAOS was not mutagenic in the Ames test. Positive results were obtained in the chromosome

Safety evaluation of pectin-derived acidic oligosaccharides (pAOS): Genotoxicity and sub-chronic studies

NARCIS (Netherlands)

Garthoff, J.A.; Heemskerk, S.; Hempenius, R.A.; Lina, B.A.R.; Krul, C.A.M.; Koeman, J.H.; Speijers, G.J.A.

2010-01-01

Pectin-derived acidic oligosaccharides (pAOS) are non-digestible carbohydrates to be used in infant formulae and medical nutrition. To support its safety, the genotoxic potential of pAOS was evaluated. pAOS was not mutagenic in the Ames test. Positive results were obtained in the chromosome

Bile salts and their importance for drug absorption

DEFF Research Database (Denmark)

Holm, René; Müllertz, Anette; Mu, Huiling

2013-01-01

Bile salts are present in the intestines of humans as well as the animals used during the development of pharmaceutical products. This review provides a short introduction into the physical chemical properties of bile salts, a description of the bile concentration and composition of bile...... in different animal species and an overview of the literature investigating the influence of bile salts on the in vivo performance of different compounds and drug formulations. Generally, there is a positive effect on bioavailability when bile is present in the gastro-intestinal tract, independent...

Bile salts stimulate mucin secretion by cultured dog gallbladder epithelial cells independent of their detergent effect.

OpenAIRE

Klinkspoor, J H; Yoshida, T; Lee, S P

1998-01-01

1. Bile salts stimulate mucin secretion by the gallbladder epithelium. We have investigated whether this stimulatory effect is due to a detergent effect of bile salts. 2. The bile salts taurocholic acid (TC) and tauroursodeoxycholic acid (TUDC) and the detergents Triton X-100 (12.5-400 microM) and Tween-20 (0.1-3.2 mM) were applied to monolayers of cultured dog gallbladder epithelial cells. Mucin secretion was studied by measuring the secretion of [3H]N-acetyl-d-glucosamine-labelled glycoprot...

Effect of inulin and pectin on physicochemical characteristics and stability of meat batters

Science.gov (United States)

The aim of this study was to investigate levels of inulin and pectin replacing pork back fat (BF) in meat batters (MB) of frankfurter sausage. Six treatments were evaluated: control (T1), control + 70% BF (T2), control + 85% BF + 15% inulin (T3), control + 70% BF + 30% inulin (T4), control + 85% B...

Borehole closure in salt

International Nuclear Information System (INIS)

Fuenkajorn, K.; Daemen, J.J.K.

1988-12-01

Constitutive law parameters are determined from salt behavior characterization experiments. The results are applied to predict creep (time-dependent) closure of boreholes in salt specimens subjected to various loading configurations. Rheological models (linear and nonlinear viscoelastic and viscoplastic models), empirical models, and physical theory models have been formulated from the results of uniaxial creep tests, strain and stress rate controlled uniaxial tests, constant strain rate triaxial tests, cyclic loading tests, and seismic velocity measurements. Analytical solutions for a thick-walled cylinder subjected to internal and external pressures and for a circular hole in an infinite plate subjected to a biaxial or uniaxial stressfield have been derived from each of the linear viscoelastic models and from one of the empirical laws. The experimental results indicate that the salt samples behave as an elastic-viscoplastic material. The elastic behavior tends to be linear and time-independent. The plastic deformation is time-dependent. The stress increment to strain rate increment ratio gradually decreases as the stress level increases. The transient potential creep law seems to give the simplest satisfactory governing equation describing the viscoplastic behavior of salt during the transient phase. 204 refs., 27 figs., 29 tabs

Decontamination abilities of some foodstuffs enriched with low-esterificated pectin

International Nuclear Information System (INIS)

Shtereva, V.; Kiradzhiev, G.; Paskalev, Z.; Genchev, E.

1993-01-01

Radioprotective foodstuffs prepared from mousses of beet, apricot and hip, containing low-esterificated pectin, have been prepared. Their abilities to reduce the resorption of radionuclides in the digestive tract have been investigated. These are evaluated with respect to cesium-137 and cerium-144. The changes in nuclide accumulation have been controlled by measuring the whole-body activity and radiometry of the critical organs. Among the studied mousses the hip mousse proved to be the most effective towards radioactive cesium. Efficacy towards cerium has not been found. (author)

Influence of prefermentary clarification on the composition of apple musts.

Science.gov (United States)

Hubert, Bertrand; Baron, Alain; Le Quere, Jean-Michel; Renard, Catherine M G C

2007-06-27

The polyphenol contents and colors of cider apple juices were compared before (NCM, not clarified must) and after five clarification treatments: enzymatic depectinization by pectinases followed by (i) sedimentation (depectinized and decanted juice), (ii) tangential microfiltration (microfiltered juice) or (iii) fining using gelatin (gelatin-treated juice); (iv) enzymatic gelification of pectin by pectin methylesterase followed by natural keeving by a cider manufacturer (producer keeved juice), or (v) flotation (floated with nitrogen gas juice). The pressing of the apples led to the highly selective extraction of the flavan-3-ols with the lowest molecular weights: In the apples, the number average degree of polymerization of the flavanols was 14.7, and it dropped to 2.2 in the NCM. Keeving had the highest impact on the reduction of both flavanol content and number average degree of polymerization. The flavanol concentrations were decreased in the permeate by fining (30%) much more than by depectinization. The clarification step led to a further decrease of the number average degree of polymerization. Hydroxycinnamic acids were less affected by the extraction process (with extraction yields >50%) and not affected by clarification. The color evolved with all treatments: L*, a*, b*, and chromaticity distance index measures indicated a reduction of orange-yellow saturation except after sedimentation.

Dietary salt restriction improves cardiac and adipose tissue pathology independently of obesity in a rat model of metabolic syndrome.

Science.gov (United States)

Hattori, Takuya; Murase, Tamayo; Takatsu, Miwa; Nagasawa, Kai; Matsuura, Natsumi; Watanabe, Shogo; Murohara, Toyoaki; Nagata, Kohzo

2014-12-02

Metabolic syndrome (MetS) enhances salt sensitivity of blood pressure and is an important risk factor for cardiovascular disease. The effects of dietary salt restriction on cardiac pathology associated with metabolic syndrome remain unclear. We investigated whether dietary salt restriction might ameliorate cardiac injury in DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, which are derived from a cross between Dahl salt-sensitive and Zucker rats and represent a model of metabolic syndrome. DS/obese rats were fed a normal-salt (0.36% NaCl in chow) or low-salt (0.0466% NaCl in chow) diet from 9 weeks of age and were compared with similarly treated homozygous lean littermates (DahlS.Z-Lepr(+)/Lepr(+), or DS/lean rats). DS/obese rats fed the normal-salt diet progressively developed hypertension and showed left ventricular hypertrophy, fibrosis, and diastolic dysfunction at 15 weeks. Dietary salt restriction attenuated all of these changes in DS/obese rats. The levels of cardiac oxidative stress and inflammation and the expression of cardiac renin-angiotensin-aldosterone system genes were increased in DS/obese rats fed the normal-salt diet, and dietary salt restriction downregulated these parameters in both DS/obese and DS/lean rats. In addition, dietary salt restriction attenuated the increase in visceral adipose tissue inflammation and the decrease in insulin signaling apparent in DS/obese rats without reducing body weight or visceral adipocyte size. Dietary salt restriction did not alter fasting serum glucose levels but it markedly decreased the fasting serum insulin concentration in DS/obese rats. Dietary salt restriction not only prevents hypertension and cardiac injury but also ameliorates insulin resistance, without reducing obesity, in this model of metabolic syndrome. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Combinatorial enzyme technology: Conversion of pectin to oligo species and its effect on microbial growth

Science.gov (United States)

Plant cell wall polysaccharides, which consist of polymeric backbones with various types of substitution, were studied using the concept of combinatorial enzyme technology for conversion of agricultural fibers to functional products. Using citrus pectin as the starting substrate, an active oligo spe...

Effects of high hydrostatic pressure and temperature increase on Escherichia coli spp. and pectin methyl esterase inactivation in orange juice.

Science.gov (United States)

Torres, E F; González-M, G; Klotz, B; Rodrigo, D

2016-03-01

The aim of this study was to evaluate the effect of high hydrostatic pressure treatment combined with moderate processing temperatures (25 ℃-50 ℃) on the inactivation of Escherichia coli O157: H7 (ATCC 700728), E. coli K12 (ATCC 23716), and pectin methyl esterase in orange juice, using pressures of 250 to 500 MPa with times ranging between 1 and 30 min. Loss of viability of E. coli O157:H7 increased significantly as pressure and treatment time increased, achieving a 6.5 log cycle reduction at 400 MPa for 3 min at 25 ℃ of treatment. With regard to the inactivation of pectin methyl esterase, the greatest reduction obtained was 90.05 ± 0.01% at 50 ℃ and 500 MPa of pressure for 15 min; therefore, the pectin methyl esterase enzyme was highly resistant to the treatments by high hydrostatic pressure. The results obtained in this study showed a synergistic effect between the high pressure and moderate temperatures in inactivating E. coli cells. © The Author(s) 2016.

Microencapsulation of sulforaphane from broccoli seed extracts by gelatin/gum arabic and gelatin/pectin complexes.

Science.gov (United States)

García-Saldaña, Jesús S; Campas-Baypoli, Olga N; López-Cervantes, Jaime; Sánchez-Machado, Dalia I; Cantú-Soto, Ernesto U; Rodríguez-Ramírez, Roberto

2016-06-15

Sulforaphane is a phytochemical that has received attention in recent years due to its chemopreventive properties. However, the uses and applications of this compound are very limited, because is an unstable molecule that is degraded mainly by changes in temperature and pH. In this research, the use of food grade polymers for microencapsulation of sulforaphane was studied by a complex coacervation method using the interaction of oppositely charged polymers as gelatin/gum arabic and gelatin/pectin. The polymers used were previously characterized in moisture content, ash and nitrogen. The encapsulation yield was over 80%. The gelatin/pectin complex had highest encapsulation efficiency with 17.91%. The presence of sulforaphane in the complexes was confirmed by FTIR and UV/visible spectroscopy. The materials used in this work could be a new and attractive option for the protection of sulforaphane. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bile duct proliferation associated with bile salt-induced hypercholeresis in Mdr2 P-glycoprotein-deficient mice

NARCIS (Netherlands)

Hulzebos, CV; Voshol, PJ; Wolters, H; Kruit, JK; Ottenhof, R; Groen, AK; Stellaard, F; Verkade, HJ; Kuipers, F

Baekground/Aims: Bile flow consists of bile salt-dependent bile flow (BSDF), generated by canalicular secretion of bile salts, and bile salt-independent flow (BSIF), probably of combined canalicular and ductular origin. Bile salt transport proteins have been identified in cholangiocytes suggesting a

Continuous Production of Ethanol from Starch Using Glucoamylase and Yeast Co-Immobilized in Pectin Gel

Science.gov (United States)

Giordano, Raquel L. C.; Trovati, Joubert; Schmidell, Willibaldo

This work presents a continuous simultaneous saccharification and fermentation (SSF) process to produce ethanol from starch using glucoamylase and Saccharomyces cerevisiae co-immobilized in pectin gel. The enzyme was immobilized on macroporous silica, after silanization and activation of the support with glutaraldehyde. The silicaenzyme derivative was co-immobilized with yeast in pectin gel. This biocatalyst was used to produce ethanol from liquefied manioc root flour syrup, in three fixed bed reactors. The initial reactor yeast load was 0.05 g wet yeast/ml of reactor (0.1 g wet yeast/g gel), used in all SSF experiments. The enzyme concentration in the reactor was defined by running SSF batch assays, using different amount of silica-enzyme derivative, co-immobilized with yeast in pectin gel. The chosen reactor enzyme concentration, 3.77 U/ml, allowed fermentation to be the rate-limiting step in the batch experiment. In this condition, using initial substrate concentration of 166.0 g/1 of total reducing sugars (TRS), 1 ml gel/1 ml of medium, ethanol productivity of 8.3 g/l/h was achieved, for total conversion of starch to ethanol and 91% of the theoretical yield. In the continuous runs, feeding 163.0 g/1 of TRS and using the same enzyme and yeast concentrations used in the batch run, ethanol productivity was 5.9 g ethanol/1/h, with 97% of substrate conversion and 81% of the ethanol theoretical yield. Diffusion effects in the extra-biocatalyst film seemed to be reduced when operating at superficial velocities above 3.7 × 10-4 cm/s.

Relative bioavailability of 13C5-folic acid in pectin-coated folate fortified rice in humans using stable isotope techniques.

Science.gov (United States)

de Ambrosis, A; Vishnumohan, S; Paterson, J; Haber, P; Arcot, J

2017-01-01

The aim of the study was to measure the relative bioavailability of labeled pteroylglutamic acid (13C5-PteGlu) from a pectin-coated fortified rice in vivo to measure any effect of the edible coating on folic acid bioavailability. Healthy volunteers (N=26) aged 18-39 years received three test meals in three randomized short-term cross-over trials: Trial 1: aqueous 400 μg 13C5-PteGlu, Trial 2: 200 g cooked white rice+400 μg 13C5-PteGlu,Trial 3: 200 g fortified cooked white rice with pectin-coated premix containing 400 μg 13C5-PteGlu. Blood samples were drawn at 0,1,2,5 and 8 h postprandial. The concentration of 13C5-5 methyl-tetrahydrofolate appearing in plasma was quantified using high performance liquid chromatography-mass spectrometry (MS)/MS. For 24 h before baseline estimation and during the area under the curve (AUC) study, the subjects were placed on a low folate diet (∼100 μg/day). The relative bioavailability of the folic acid following Trial 3 was measured by comparing the 13C5-5 methyl-tetrahydrofuran (THF) AUC with Trials 1 and 2. The bioavailability of folic acid in a pectin-coated rice premix was 68.7% (range 47-105) and 86.5% (range 65-115) in uncoated fortified rice relative to aqueous folic acid. This study is the first demonstration of the bioavailability of folate in pectin-coated fortified rice in humans.

Laboratory simulation of salt dissolution during waste removal

International Nuclear Information System (INIS)

Wiersma, B.J.; Parish, W.R.

1997-01-01

Laboratory experiments were performed to support the field demonstration of improved techniques for salt dissolution in waste tanks at the Savannah River Site. The tests were designed to investigate three density driven techniques for salt dissolution: (1) Drain-Add-Sit-Remove, (2) Modified Density Gradient, and (3) Continuous Salt Mining. Salt dissolution was observed to be a very rapid process as salt solutions with densities between 1.38-1.4 were frequently removed. Slower addition and removal rates and locating the outlet line at deeper levels below the top of the saltcake provided the best contact between the dissolution water and the saltcake. It was observed that dissolution with 1 M sodium hydroxide solution resulted in salt solutions that were within the current inhibitor requirements for the prevention of stress corrosion cracking. This result was independent of the density driven technique. However, if inhibited water (0.01 M sodium hydroxide and 0.011 M sodium nitrite) was utilized, the salt solutions were frequently outside the inhibitor requirements. Corrosion testing at conditions similar to the environments expected during waste removal was recommended

User's manual and guide to SALT3 and SALT4: two-dimensional computer codes for analysis of test-scale underground excavations for the disposal of radioactive waste in bedded salt deposits

International Nuclear Information System (INIS)

Lindner, E.N.; St John, C.M.; Hart, R.D.

1984-02-01

SALT3 and SALT4 are two-dimensional analytical/displacement-discontinuity codes designed to evaluate temperatures, deformation, and stresses associated with underground disposal of radioactive waste in bedded salt. These codes were developed by the University of Minnesota for the Office of Nuclear Waste Isolation in 1979. The present documentation describes the mathematical equations of the physical system being modeled, the numerical techniques utilized, and the organization of these computer codes. The SALT3 and SALT4 codes can simulate: (a) viscoelastic behavior in pillars adjacent to excavations; (b) transversely isotropic elastic moduli such as those exhibited by bedded or stratified rock; and (c) excavation sequence. Major advantages of these codes are: (a) computational efficiency; (b) the small amount of input data required; and (c) a creep law based on laboratory experimental data for salt. The main disadvantage is that some of the assumptions in the formulation of the codes, i.e., the homogeneous elastic half-space and temperature-independent material properties, render it unsuitable for canister-scale analysis or analysis of lateral deformation of the pillars. The SALT3 and SALT4 codes can be used for parameter sensitivity analyses of two-dimensional, repository-scale, thermomechanical response in bedded salt during the excavation, operational, and post-closure phases. It is especially useful in evaluating alternative patterns and sequences of excavation or waste canister placement. SALT3 is a refinement of an earlier code, SALT, and includes a fully anelastic creep model and thermal stress routine. SALT4 is a later version, and incorporates a revised creep model which is strain-hardening

Bile salts stimulate mucin secretion by cultured dog gallbladder epithelial cells independent of their detergent effect.

Science.gov (United States)

Klinkspoor, J H; Yoshida, T; Lee, S P

1998-05-15

1. Bile salts stimulate mucin secretion by the gallbladder epithelium. We have investigated whether this stimulatory effect is due to a detergent effect of bile salts. 2. The bile salts taurocholic acid (TC) and tauroursodeoxycholic acid (TUDC) and the detergents Triton X-100 (12.5-400 microM) and Tween-20 (0.1-3.2 mM) were applied to monolayers of cultured dog gallbladder epithelial cells. Mucin secretion was studied by measuring the secretion of [3H]N-acetyl-d-glucosamine-labelled glycoproteins. We also attempted to alter the fluidity of the apical membrane of the cells through extraction of cholesterol with beta-cyclodextrin (2.5-15 mM). The effect on TUDC-induced mucin secretion was studied. Cell viability was assessed by measuring lactate dehydrogenase (LDH) leakage or 51Cr release. 3. In contrast with the bile salts, the detergents were not able to cause an increase in mucin secretion without causing concomitant cell lysis. Concentrations of detergent that increased mucin release (>100 microM Triton X-100, >0.8 mM Tween-20), caused increased LDH release. Incubation with beta-cyclodextrin resulted in effective extraction of cholesterol without causing an increase in 51Cr release. However, no effect of the presumed altered membrane fluidity on TUDC (10 mM)-induced mucin secretion was observed. 4. The stimulatory effect of bile salts on mucin secretion by gallbladder epithelial cells is not affected by the fluidity of the apical membrane of the cells and also cannot be mimicked by other detergents. We conclude that the ability of bile salts to cause mucin secretion by the gallbladder epithelium is not determined by their detergent properties.

Polygalacturonase production by AR2 pectinolytic bacteria through submerged fermentation of raja nangka banana peel (Musa paradisiaca var. formatypica) with variation of carbon source and pectin

Science.gov (United States)

Utami, R.; Widowati, E.; Ivenaria, A.; Mahajoeno, E.

2017-04-01

Polygalacturonase (EC 3.1.2.15) catalyzes the hydrolysis of α-1,4-glycosidic bonds on galacturonic acid. Polygalacturonase can be produced from AR2 pectinolytic bacteria isolated from orange peel and vegetable waste. Commonly cost production of enzymes were high. However, with the advancement of technology, enzymes can now be manufactured at a low cost. Production of enzymes in low cost media with agro-industrial waste is interesting. Raja nangka banana peel is agro-industrial waste that is uneconomic. Therefore, this material can be used as a pectin source in polygalacturonase production. Polygalacturonase was produced by AR2 pectinolytic bacteria with the addition of various carbon sources (1% glucose, 1% galactose, 1% lactose) and variation of pectin concentrations (5%; 7.5%; 10%). This study used submerged fermentation with a cultivation temperature of 55°C and an agitation speed of 144 rpm for a 48-h incubation time. The results showed that variation of carbon sources and pectin concentrations affected the production of polygalacturonase. After 48 h fermentation, the results showed that the number of cells of samples ranged from 8.3 to 9.445 log cells/mL; the used pectin of samples ranged from 87.170-93.745%; and the polygalacturonase activity of samples ranged from 0.030 to 0.151 U/mL. The highest polygalacturonase activity was obtained by production of polygalacturonase on 1% glucose and 10% pectin medium.

Extraction, characterization and gelling behavior enhancement of pectins from the cladodes of Opuntia ficus indica.

Science.gov (United States)

Lefsih, Khalef; Delattre, Cédric; Pierre, Guillaume; Michaud, Philippe; Aminabhavi, Tejraj M; Dahmoune, Farid; Madani, Khodir

2016-01-01

Total Pectins Fraction (TPF) was extracted at room temperature from dried cladodes of Opuntia ficus indica. TPF is constituted of three pectic fractions WSP, CSP and ASP, which are made up of 66.6%, 44.3% and 81.1% (w/w) of galacturonic acid, respectively. The antioxidant ability of TPF increased with the concentration increasing. It scavenged hydroxyl radical by 90% and chelated 90% of ferrous ions at 5 g/L. FTIR study was carried out. Strong characteristic absorption peaks at 1,618 cm(-1) assigned to the vibration of COO(-) group of galacturonic acid. In the fingerprint region, we noticed three well-defined peaks at 1054, 1085, and 1,154 cm(-1) characteristic of pectic polysaccharides. TPF are non-gelling pectins. The co-crosslinking of TPF with carrageenan was carried out and the gelling behavior was successfully improved. Thermo-sensitive hydrogel was obtained with 82% of TPF and 18% of carrageenan (w/w). Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of gamma irradiation in the viscosity of gelatin and pectin solutions used in food industry; Efeito da radiacao gama sobre a viscosidade de solucoes de gelatina e pectina utilizadas na industria de alimentos

Energy Technology Data Exchange (ETDEWEB)

Inamura, Patricia Yoko

2008-07-01

Pectin is a polysaccharide substance of plant origin that may be used as gelling agent, stabilizer in jams, in yogurt drinks and lactic acid beverages. Gelatin, a protein from bovine origin, in this case, is mainly used as gelling agent due to hydrogel formation during cooling. The {sup 60} Co-irradiation process may cause various modifications in macromolecules, some with industrial application, as reticulation. The dynamic response of viscoelastic materials can be used in order to give information about the structural aspect of a system at molecular level. In the present work samples of pectin with different degree of methoxylation, gelatin and the mixture of both were employed to study the radiation sensitivity by means of viscosity measurements. Solutions prepared with citric pectin with high methoxylation content (ATM) 1 por cent, pectin with low content (BTM) 1 por cent, gelatin 0.5 por cent, 1 por cent and 2 por cent, and the mixture 1 por cent and 2 por cent were irradiated with gamma rays at different doses, up to 15 kGy with dose rate about 2 kGy/h. After irradiation the viscosity was measured within a period of 48 h. The viscosity of ATM and BTM pectin solutions decreased sharply with the radiation dose. However, the gelatin sample presented a great radiation resistance. When pectin and gelatin solutions were mixed a predominance of pectin behavior was found. (author)

Thiolated citrus low-methoxyl pectin: Synthesis, characterization and rheological and oxidation-responsive gelling properties.

Science.gov (United States)

Chen, Jinfeng; Ye, Fayin; Zhou, Yun; Zhao, Guohua

2018-02-01

In the present study, citrus low-methoxyl pectin was modified by conjugating cysteine via amide bonds, and the resultant polymer (CYS-PEC) was characterized. CYS-PEC conjugates with thiol contents varying from 77.8μmol/g to 296μmol/g were synthesized, and the successful conjugation was evidenced by elemental, and FT-IR analyses. The sulfur in CYS-PEC is predominately in the thiol form, with a minor fraction forming disulfide bonds (∼15%), which occur when thiol/disulfide interchange interrupts the intended thiolation. Both native and modified pectin dispersions exhibited strong pseudoplastic properties, and the frequency sweeps revealed them to be dispersions containing microgel particles. Dynamic viscoelastic analysis was used to determine the oxidation-response gelling capacities of polymer dispersions containing H 2 O 2 , especially those that are highly thiolated and have cross-linked gel properties. For oxidation-induced CYS-PEC gels, their gelation time, hardness, viscosity and elastic moduli and swelling-disintegration ratio are dependent on the thiol group content, H 2 O 2 concentration and polymer concentration. Copyright © 2017 Elsevier Ltd. All rights reserved.

Microparticulated whey protein-pectin complex: A texture-controllable gel for low-fat mayonnaise.

Science.gov (United States)

Sun, Chanchan; Liu, Rui; Liang, Bin; Wu, Tao; Sui, Wenjie; Zhang, Min

2018-06-01

This article reports caloric value changes, stability and rheological properties of mayonnaises affected by fat mimetic based on Microparticulated whey protein (MWP) and high-methoxy pectin. Lipid was partially substituted at different levels of 20%, 40%, 60%, 80% and 100%, and the samples were referred to as FM20, FM40, FM60, FM80 and FFM, respectively. The full fat (FF) mayonnaise was used as a control experiment. For rheological properties, the addition of fat mimetic resulted in the gradual decrease of pseudoplastic behavior, relative thixotropic area and viscosity index, while elasticity index exhibited the opposite trend. After 30 days of storage, all mayonnaises except FM20 were categorized as weak gels under oscillatory tests, while FM20 displayed high storage stability. Long-term stability studies showed that the addition of the fat mimetic up to 60% could significantly enhance the storage stability of mayonnaises by preventing the coalescence and flocculation of the droplets. Both the dynamic mechanical measurement and stability study results suggested that MWP and pectin could be a potential fat mimetic used in mayonnaise. Copyright © 2018 Elsevier Ltd. All rights reserved.

Carbon nanotubes/pectin/minerals substituted apatite nanocomposite depositions on anodized titanium for hard tissue implant: In vivo biological performance"†

International Nuclear Information System (INIS)

Govindaraj, Dharman; Rajan, Mariappan; Munusamy, Murugan A.; Alarfaj, Abdullah A.; Higuchi, Akon; Suresh Kumar, S.

2017-01-01

A surface deposition approach enveloping the use of biocompatible trace components and strengthening materials will affect the physicochemical and osseointegration properties of nanocomposite deposited implants. The current work is aimed at the development of functionalized carbon nanotubes (f-CNT)/Pectin (P)/mineralized hydroxyapatite (M-HA) ((f-CNT/P/M-HA)) nanocomposite depositions by electrophoretic deposition on anodized titanium (TiO_2) implant. The capacity of f-CNT manages the cost of mechanical strength, while pectin (extracted from pomegranate peel) and minerals (strontium, magnesium, and zinc) enhance the biocompatibility of the HA deposition was investigate utilizing different methods. The functional and morphological analyses were done by FTIR, XRD, XPS, SEM-EDX and TEM. The mechanical depiction results show improved adherence quality for the nanocomposite deposition. Additionally, an enhanced viability of osteoblast cells (MG63 (HOS)) was monitored in vitro on the f-CNT/P/M-HA nanocomposite deposition. The capacity of the nanocomposite deposited TiO_2 implant to encourage bone development was assessed in vivo. Hence, the as-synthesized nanocomposite deposited TiO_2 that joins the comfort osteoconductivity of mineralized hydroxyapatite, pectin collectively with the compressive strength of f-CNT can have numerous uses in orthopaedics since it could enhance implant fixation in human bone. - Highlights: • Successful development of CNTs–Pectin reinforced M-HA nanocomposite coating on TiO_2 by electrodeposition. • The success of nanocomposite coatings was evidenced with FTIR, XRD, XPS, SEM-EDX, and TEM. • Nanocomposite coating on TiO_2 is bio-resistive, better candidate for implant applications. • The fabricate nanocomposite coatings showed good biocompatibility and no adverse effect from in vitro and in vivo tests.

Vascular effects of a single high salt meal

Directory of Open Access Journals (Sweden)

Mohamed Abdel Kader Abdel Wahab

2016-09-01

Conclusion: High salt intake may acutely impair vascular function in different vascular beds independent of the increase of blood pressure. Plasma sodium increase may be one of the underlying mechanisms.

Ultrasonic extraction of pectin from Opuntia ficus indica cladodes after mucilage removal: Optimization of experimental conditions and evaluation of chemical and functional properties.

Science.gov (United States)

Bayar, Nadia; Bouallegue, Tahani; Achour, Mabrouka; Kriaa, Mouna; Bougatef, Ali; Kammoun, Radhouane

2017-11-15

Ultrasonic assisted extraction (UAE) of pectin from Opuntia ficus indica (OFI) cladodes after mucilage removal was attempted using the response surface methodology. The process variables were optimized by the isovariant central composite design in order to improve the pectin extraction yield. The optimum condition obtained was: sonication time 70min, temperature 70°C, pH 1.5 and the water-material ratio 30ml/g. This condition was validated and the performance of experimental extraction was 18.14%±1.41%, which was closely linked to the predicted value (19.06%). Thus, UAE present a promising alternative to conventional extraction process thanks to its high efficiency which was achieved in less time and at lower temperatures. The pectin extracted by UAE from OFI cladodes (UAEPC) has a low degree of esterification, high uronic acid content, important functional properties and good anti-radical activity. These results are in favor of the use of UAEPC as potential additive in food industry. Copyright © 2017. Published by Elsevier Ltd.

Development of diclofenac sodium loaded magnetic nanocarriers of pectin interacted with chitosan for targeted and sustained drug delivery.

Science.gov (United States)

Dutta, Raj Kumar; Sahu, Saurabh

2012-09-01

A novel spherical magnetic nanocarrier of 100-150 nm dimensions made of pectin interacted with chitosan (MPCh-DS0.05) resulted in 99.5% encapsulation efficiency of diclofenac sodium (DS) as a model drug. Similarly, magnetic nanocarrier made of only pectin crosslinked with Ca(2+) (MPDS-0.05) resulted in only 60.6% encapsulation efficiency of DS. The increase in drug encapsulation efficiency (%) in MPCh-DS0.05 batch was due to synergistic drug encapsulation properties of pectin and chitosan. The structural and morphological features of these magnetic nanocarriers were studied by X-ray diffractometry (XRD), Fourier transform infrared-spectrometry (FT-IR), thermogravimetry, electron microscopy and dynamic light scattering (DLS) measurements. The magnetic properties were measured by vibrating sample magnetometer (VSM) and superconducting quantum unit interference device measurements (SQUID). The in vitro drug release was pH sensitive and exhibited sustained release sequentially in simulated gastric fluid (negligible release in 0-2h), simulated intestinal fluid (~69% release in 2-5h), simulated colonic fluid (5-60 h) and also in phosphate buffer at pH 7.4 (0-48 h). The drug release profile in phosphate buffer solution at pH 7.4 was in good agreement with swelling controlled mechanism on the basis of Korsemeyer-Peppas model. Copyright © 2012 Elsevier B.V. All rights reserved.

Electrodeposition of copper nanoparticles using pectin scaffold at graphene nanosheets for electrochemical sensing of glucose and hydrogen peroxide

International Nuclear Information System (INIS)

Mani, Veerappan; Devasenathipathy, Rajkumar; Chen, Shen-Ming; Wang, Sea-Fue; Devi, Parvathy; Tai, Yian

2015-01-01

A simple electrodeposition approach has been described for the preparation of copper nanoparticles (CuNPs) using biopolymer pectin as a scaffold and graphene as a support. The formation of graphene/pectin-CuNPs was confirmed by scanning electron microscopy, UV-Visible spectroscopy and X-ray diffraction studies. The graphene/pectin-CuNPs film modified electrode was prepared and its electrocatalytic applications to the oxidation of glucose and reduction of H 2 O 2 have been explored. An amperometric glucose sensor was fabricated which exhibited excellent sensor performance in terms of wide linear range (10 μM–5.5 mM), low detection limit (2.1 μM) and high sensitivity (0.0457 μAμM −1 cm −2 ). Likewise, an amperometric sensor has been fabricated for the determination of H 2 O 2 which displayed linear range of 1 μM–1 mM, detection limit of 0.35 μM and sensitivity of 0.391 μAμM −1 cm −2 . The sensor displayed appreciable repeatability, reproducibity and stability. Furthermore, practical feasibility of the sensor has been demonstrated in human serum and contact lens cleaning solution to determine glucose and H 2 O 2 , respectively. The main advantages of sensor include simple and green fabrication approach, roughed and stable electrode matrix, high sensitivity and stability, fast in sensing and highly reproducible

Effects of apples and specific apple components on the cecal environment of conventional rats: role of apple pectin.

Science.gov (United States)

Licht, Tine R; Hansen, Max; Bergström, Anders; Poulsen, Morten; Krath, Britta N; Markowski, Jaroslaw; Dragsted, Lars O; Wilcks, Andrea

2010-01-20

Our study was part of the large European project ISAFRUIT aiming to reveal the biological explanations for the epidemiologically well-established health effects of fruits. The objective was to identify effects of apple and apple product consumption on the composition of the cecal microbial community in rats, as well as on a number of cecal parameters, which may be influenced by a changed microbiota. Principal Component Analysis (PCA) of cecal microbiota profiles obtained by PCR-DGGE targeting bacterial 16S rRNA genes showed an effect of whole apples in a long-term feeding study (14 weeks), while no effects of apple juice, purée or pomace on microbial composition in cecum were observed. Administration of either 0.33 or 3.3% apple pectin in the diet resulted in considerable changes in the DGGE profiles.A 2-fold increase in the activity of beta-glucuronidase was observed in animals fed with pectin (7% in the diet) for four weeks, as compared to control animals (P apple-fed rats in the four-week study (P apple pectin (7% in the diet) increases the population of butyrate- and beta-glucuronidase producing Clostridiales, and decreases the population of specific species within the Bacteroidetes group in the rat gut. Similar changes were not caused by consumption of whole apples, apple juice, purée or pomace.

Effects of temperature, ultraviolet radiation and pectin methyl esterase on aerobic methane release from plant material

DEFF Research Database (Denmark)

Bruhn, Dan; Mikkelsen, Teis Nørgaard; Øbro, J.

2009-01-01

exponentially on temperature and linearly on UV-B irradiance. UV-B had a greater stimulating effect than UV-A, while visible light had no effect on emission rates. PME was found to substantially reduce the potential for aerobic CH4 emissions upon demethylation of pectin....

Spray dried microparticles of chia oil using emulsion stabilized by whey protein concentrate and pectin by electrostatic deposition.

Science.gov (United States)

Noello, C; Carvalho, A G S; Silva, V M; Hubinger, M D

2016-11-01

Chia seed oil has a high content of α-linolenic acid (60%) and linoleic acid (20%). Use of this oil in different products is limited due to its liquid state, and the presence of insaturation is a trigger for oxidation. In this context, to facilitate the incorporation of chia oil in food products and increase its protection against oxidation, the aim of this work was to produce chia oil microparticles by spray drying using emulsions stabilized by whey protein concentrate (ζ-potential +13.4 at pH3.8) and pectin (ζ-potential -40.4 at pH3.8) through the electrostatic layer-by-layer deposition technique and emulsions prepared with only whey protein concentrate. Emulsions stabilized by whey protein concentrate and stabilized by whey protein concentrate-pectin were prepared using maltodextrin (10 DE) and modified starch (Hi-Cap® 100). They were characterized in relation to stability, droplet size, ζ-Potential and optical microscopy. The microparticles were characterized in relation to moisture content, water activity, particle size, microstructure and oxidative stability by the Rancimat method. Emulsions stabilized by whey protein concentrate-pectin with added maltodextrin 10 DE and emulsions stabilized by whey protein concentrate with added modified starch (Hi-Cap® 100) were stable after 24h. Emulsions stabilized by whey protein concentrate and by whey protein concentrate-pectin showed droplets with mean diameter ranging from 0.80 to 1.31μm, respectively and ζ-potential varying from -6.9 to -27.43mV, respectively. After spray drying, the microparticles showed an mean diameter ranging from 7.00 to 9.00μm. All samples presented high encapsulation efficiency values, above 99%. Microparticles produced with modified starch showed a smoother spherical surface than particles with maltodextrin 10 DE, which presented a wrinkled surface. All microparticles exhibited higher oxidative stability than chia oil in pure form. Copyright © 2016 Elsevier Ltd. All rights reserved.

Three pectin methylesterase inhibitors protect cell wall integrity for arabidopsis immunity to Botrytis

DEFF Research Database (Denmark)

Lionetti, Vincenzo; Fabri, Eleonora; Caroli, Monica De

2017-01-01

to the control plants. A higher stimulation of the fungal oxalic acid biosynthetic pathway also can contribute to the higher susceptibility of pmei mutants. The lack of PMEI expression does not affect hemicellulose strengthening, callose deposition, and the synthesis of structural defense proteins, proposed...... is posttranscriptionally regulated by endogenous protein inhibitors (PMEIs). Here, AtPMEI10, AtPMEI11, and AtPMEI12 are identified as functional PMEIs induced in Arabidopsis (Arabidopsis thaliana) during B. cinerea infection. AtPMEI expression is strictly regulated by jasmonic acid and ethylene signaling, while only At...

Mode of action of pectin lyase A of Aspergillus niger on differently C6-substituted oligogalacturonides

NARCIS (Netherlands)

Alebeek, van G.J.W.M.; Christensen, T.M.I.E.; Schols, H.A.; Mikkelsen, J.D.; Voragen, A.G.J.

2002-01-01

A thorough investigation of the mode of action of Aspergillus niger (4M-147) pectin lyase A (PLA) on differently C6-substituted oligogalacturonides is described. PLA appeared to be very specific for fully methyl-esterified oligogalacturonides: removal of the methyl-ester or changing the type of

Pectin Enhances Bio-Control Efficacy by Inducing Colonization and Secretion of Secondary Metabolites by Bacillus amyloliquefaciens SQY 162 in the Rhizosphere of Tobacco.

Directory of Open Access Journals (Sweden)

Kai Wu

Full Text Available Bacillus amyloliquefaciens is a plant-beneficial Gram-positive bacterium involved in suppressing soil-borne pathogens through the secretion of secondary metabolites and high rhizosphere competence. Biofilm formation is regarded as a prerequisite for high rhizosphere competence. In this work, we show that plant extracts affect the chemotaxis and biofilm formation of B. amyloliquefaciens SQY 162 (SQY 162. All carbohydrates tested induced the chemotaxis and biofilm formation of the SQY 162 strain; however, the bacterial growth rate was not influenced by the addition of carbohydrates. A strong chemotactic response and biofilm formation of SQY 162 were both induced by pectin through stimulation of surfactin synthesis and transcriptional expression of biofilm formation related matrix genes. These results suggested that pectin might serve as an environmental factor in the stimulation of the biofilm formation of SQY 162. Furthermore, in pot experiments the surfactin production and the population of SQY 162 in the rhizosphere significantly increased with the addition of sucrose or pectin, whereas the abundance of the bacterial pathogen Ralstonia decreased. With increased production of secondary metabolites in the rhizosphere of tobacco by SQY 162 and improved colonization density of SQY 162 in the pectin treatment, the disease incidences of bacterial wilt were efficiently suppressed. The present study revealed that certain plant extracts might serve as energy sources or environmental cues for SQY 162 to enhance the population density on tobacco root and bio-control efficacy of tobacco bacterial wilt.

Microwave based synthesis and spectral characterization of thermo-sensitive poly(N,N-diethylacrylamide) grafted pectin copolymer.

Science.gov (United States)

Işıklan, Nuran; Tokmak, Şeyma

2018-07-01

The functionalization of polysaccharides with synthetic polymers has attracted great attention owing to its application in many industrial fields. The aim of this work was to study the impact of pectin functionalization with N,N-diethylacrylamide (DEAAm). Pectin was modified via microwave-induced graft copolymerization of DEAAm using ceric ammonium nitrate (CAN) and N,N,N',N'-tetramethylethylenediamine (TEMED). FTIR, 13 C NMR, DSC/TGA, XRD, and SEM techniques were used to verify the structure of graft copolymers. Various reaction conditions such as microwave irradiation time, temperature, microwave power, monomer, initiator, and TEMED concentrations were investigated to get a maximum grafting yield of 192%. Lower critical solution temperatures (LCST) of graft copolymers were determined by UV spectroscopy. Graft copolymers were found to be thermo-sensitive, with LCST of 31°C and high thermal resistance. Biocompatibility test of copolymers showed that copolymers were not cytotoxic to L929 fibroblasts cells and can be used as a biomaterial. Copyright © 2018 Elsevier B.V. All rights reserved.

Carbon nanotubes/pectin/minerals substituted apatite nanocomposite depositions on anodized titanium for hard tissue implant: In vivo biological performance{sup †}

Energy Technology Data Exchange (ETDEWEB)

Govindaraj, Dharman [Biomaterials in Medicinal Chemistry Lab, Department of Natural Products Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai 625021 (India); Rajan, Mariappan, E-mail: rajanm153@gmail.com [Biomaterials in Medicinal Chemistry Lab, Department of Natural Products Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai 625021 (India); Munusamy, Murugan A.; Alarfaj, Abdullah A. [Department of Botany and Microbiology, College of Science, King Saud University, Riyadh (Saudi Arabia); Higuchi, Akon [Department of Chemical and Materials Engineering, National Central University, Jhong-li, Taoyuan, 32001 Taiwan (China); Suresh Kumar, S. [Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang (Malaysia)

2017-06-15

A surface deposition approach enveloping the use of biocompatible trace components and strengthening materials will affect the physicochemical and osseointegration properties of nanocomposite deposited implants. The current work is aimed at the development of functionalized carbon nanotubes (f-CNT)/Pectin (P)/mineralized hydroxyapatite (M-HA) ((f-CNT/P/M-HA)) nanocomposite depositions by electrophoretic deposition on anodized titanium (TiO{sub 2}) implant. The capacity of f-CNT manages the cost of mechanical strength, while pectin (extracted from pomegranate peel) and minerals (strontium, magnesium, and zinc) enhance the biocompatibility of the HA deposition was investigate utilizing different methods. The functional and morphological analyses were done by FTIR, XRD, XPS, SEM-EDX and TEM. The mechanical depiction results show improved adherence quality for the nanocomposite deposition. Additionally, an enhanced viability of osteoblast cells (MG63 (HOS)) was monitored in vitro on the f-CNT/P/M-HA nanocomposite deposition. The capacity of the nanocomposite deposited TiO{sub 2} implant to encourage bone development was assessed in vivo. Hence, the as-synthesized nanocomposite deposited TiO{sub 2} that joins the comfort osteoconductivity of mineralized hydroxyapatite, pectin collectively with the compressive strength of f-CNT can have numerous uses in orthopaedics since it could enhance implant fixation in human bone. - Highlights: • Successful development of CNTs–Pectin reinforced M-HA nanocomposite coating on TiO{sub 2} by electrodeposition. • The success of nanocomposite coatings was evidenced with FTIR, XRD, XPS, SEM-EDX, and TEM. • Nanocomposite coating on TiO{sub 2} is bio-resistive, better candidate for implant applications. • The fabricate nanocomposite coatings showed good biocompatibility and no adverse effect from in vitro and in vivo tests.

Cell wall structures leading to cultivar differences in softening rates develop early during apple (Malus x domestica) fruit growth.

Science.gov (United States)

Ng, Jovyn K T; Schröder, Roswitha; Sutherland, Paul W; Hallett, Ian C; Hall, Miriam I; Prakash, Roneel; Smith, Bronwen G; Melton, Laurence D; Johnston, Jason W

2013-11-19

There is a paucity of information regarding development of fruit tissue microstructure and changes in the cell walls during fruit growth, and how these developmental processes differ between cultivars with contrasting softening behaviour. In this study we compare two apple cultivars that show different softening rates during fruit development and ripening. We investigate whether these different softening behaviours manifest themselves late during ethylene-induced softening in the ripening phase, or early during fruit expansion and maturation. 'Scifresh' (slow softening) and 'Royal Gala' (rapid softening) apples show differences in cortical microstructure and cell adhesion as early as the cell expansion phase. 'Scifresh' apples showed reduced loss of firmness and greater dry matter accumulation compared with 'Royal Gala' during early fruit development, suggesting differences in resource allocation that influence tissue structural properties. Tricellular junctions in 'Scifresh' were rich in highly-esterified pectin, contributing to stronger cell adhesion and an increased resistance to the development of large airspaces during cell expansion. Consequently, mature fruit of 'Scifresh' showed larger, more angular shaped cells than 'Royal Gala', with less airspaces and denser tissue. Stronger cell adhesion in ripe 'Scifresh' resulted in tissue fracture by cell rupture rather than by cell-to-cell-separation as seen in 'Royal Gala'. CDTA-soluble pectin differed in both cultivars during development, implicating its involvement in cell adhesion. Low pectin methylesterase activity during early stages of fruit development coupled with the lack of immuno-detectable PG was associated with increased cell adhesion in 'Scifresh'. Our results indicate that cell wall structures leading to differences in softening rates of apple fruit develop early during fruit growth and well before the induction of the ripening process.

Pectinous cell wall thickenings formation - A common defense strategy of plants to cope with Pb.

Science.gov (United States)

Krzesłowska, Magdalena; Rabęda, Irena; Basińska, Aneta; Lewandowski, Michał; Mellerowicz, Ewa J; Napieralska, Anna; Samardakiewicz, Sławomir; Woźny, Adam

2016-07-01

Lead, one of the most abundant and hazardous trace metals affecting living organisms, has been commonly detected in plant cell walls including some tolerant plants, mining ecotypes and hyperaccumulators. We have previously shown that in tip growing Funaria sp. protonemata cell wall is remodeled in response to lead by formation of thickenings rich in low-methylesterified pectins (pectin epitope JIM5 - JIM5-P) able to bind metal ions, which accumulate large amounts of Pb. Hence, it leads to the increase of cell wall capacity for Pb compartmentalization. Here we show that diverse plant species belonging to different phyla (Arabidopsis, hybrid aspen, star duckweed), form similar cell wall thickenings in response to Pb. These thickenings are formed in tip growing cells such as the root hairs, and in diffuse growing cells such as meristematic and root cap columella cells of root apices in hybrid aspen and Arabidopsis and in mesophyll cells in star duckweed fronds. Notably, all analyzed cell wall thickenings were abundant in JIM5-P and accumulated high amounts of Pb. In addition, the co-localization of JIM5-P and Pb commonly occurred in these cells. Hence, cell wall thickenings formed the extra compartment for Pb accumulation. In this way plant cells increased cell wall capacity for compartmentalization of this toxic metal, protecting protoplast from its toxicity. As cell wall thickenings occurred in diverse plant species and cell types differing in the type of growth we may conclude that pectinous cell wall thickenings formation is a widespread defense strategy of plants to cope with Pb. Moreover, detection of natural defense strategy, increasing plant cell walls capacity for metal accumulation, reveals a promising direction for enhancing plant efficiency in phytoremediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Isolation and Expression analysis of OsPME1, encoding for a putative Pectin Methyl Esterase from Oryza sativa (subsp. indica).

Science.gov (United States)

Kanneganti, Vydehi; Gupta, Aditya Kumar

2009-04-01

Pectin Methyl Esterases (PMEs) play an essential role during plant development by affecting the mechanical properties of the plant cell walls. Recent studies indicated that PMEs play important role in pollen tube development. In this study, we isolated a 1.3 kb cDNA clone from rice panicle cDNA library. It contained a 1038 bp of open reading frame (ORF) encoding for a putative pectin methyl esterase of 345 aminoacids with a 20 aminoacid signal peptide and was hence designated as OsPME1 (Oryza sativaPectin Methyl Esterase 1). It contained the structural arrangement GXYXE and GXXDFIF, found in the active groups of all PMEs. OsPME1 gene product shared varying identities, ranging from 52 % to 33 % with PMEs from other plant species belonging to Brassicaceae, Fabaceae, Amaranthaceae and Funariaceae. Southern blot analysis indicated that PME1 exists as a single copy in the rice genome. Expression pattern analysis revealed that OsPME1 is expressed only in pollen grains, during the later stages of their development and was also regulated by various abiotic stress treatments and phytohormones. Functional characterization of this pollen specific PME from rice would enable us to understand its role in pollen development.

Universal salt iodization in the Central and Eastern Europe, Commonwealth of Independent States (CEE/CIS) Region during the decade 2000-09: experiences, achievements, and lessons learned.

Science.gov (United States)

van der Haar, Frits; Gerasimov, Gregory; Tyler, Vilma Qahoush; Timmer, Arnold

2011-12-01

By 2000, the global track record on universal salt iodization (USI) indicated 26% access to adequately iodized salt in the Central and Eastern Europe, Commonwealth of Independent States (CEE/ CIS) Region. Aimed at extracting lessons learned, this study examined experiences, achievements, and outcomes of USI strategies in CEE/CIS countries during the subsequent decade. Information from the design, timing, execution, outputs, multi-sector management and results of actions by national stakeholders yielded 20 country summaries. Analysis across countries used a LogFrame Analysis typical for public nutrition development. By 2009, USI strategies had reached the target and population iodine nutrition shown adequate levels in 9 countries, while in 6 others, USI was close and/or population iodine status showed only minor imperfection. True USI, i.e., iodization of salt destined both for the food industry and the household, had been made mandatory in 13 of these 15 countries. In the Balkan area, USI and iodine nutrition advanced more than in CIS. Of the 20 sample countries, 17 (85%) had exceeded the mark of 50% adequate access, while the overall regional score reached 55% by 2010. Experience from this region suggests that strong partnership collaboration, a new concept in post-Soviet societies, was a major success factor. Voluntary iodization or focusing on household salt alone was less likely conducive for success. Achieving optimum iodine nutrition required the setting of proper iodine standard Weak political leadership insistence in the Russian Federation and Ukraine to embrace USI is the main factor why the region remains behind in the global progress.

Delayed post-harvest ripening-associated changes in Manilkara zapota L. var. Kalipatti with composite edible coating.

Science.gov (United States)

Vishwasrao, Chandrahas; Ananthanarayan, Laxmi

2017-01-01

There has been limited research on extending the shelf-life of sapota (Manilkara zapota L. var. Kalipatti) fruit. An edible coating made up of methyl cellulose (MC) and palm oil (PO) was applied to study the extension in shelf-life. Changes in physical and chemical properties of fruit were studied along with peroxidase (POD), polyphenol oxidase (PPO) and pectin methylesterase (PME) activities during post-harvest ripening of sapota. The fruits coated with 15 g L -1 MC and 11.25 g L -1 PO showed significant (P edible coating made up of MC-PO has potential to maintain the quality of sapota fruit. The edible coating extended the shelf-life of sapota fruit by 3 days preserving fruit quality up to 7 days at 24 ± 1 °C and 65 ± 5 %RH. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Cold shock treatment extends shelf life of naturally ripened or ethylene-ripened avocado fruits.

Science.gov (United States)

Chen, Jiao; Liu, Xixia; Li, Fenfang; Li, Yixing; Yuan, Debao

2017-01-01

Avocado is an important tropical fruit with high commercial value, but has a relatively short storage life. In this study, the effects of cold shock treatment (CST) on shelf life of naturally ripened and ethylene-ripened avocado fruits were investigated. Fruits were immersed in ice water for 30 min, then subjected to natural or ethylene-induced ripening. Fruit color; firmness; respiration rate; ethylene production; and the activities of polygalacturonase (PG), pectin methylesterase (PME), and endo-β-1,4-glucanase were measured. Immersion in ice water for 30 min effectively delayed ripening-associated processes, including peel discoloration, pulp softening, respiration rate, and ethylene production during shelf life. The delay in fruit softening by CST was associated with decreased PG and endo-β-1,4-glucanase activities, but not PME activity. This method could potentially be a useful postharvest technology to extend shelf life of avocado fruits.

Production of polygalacturonases by Aspergillus oryzae in stirred tank and internal- and external-loop airlift reactors.

Science.gov (United States)

Fontana, Roselei Claudete; da Silveira, Maurício Moura

2012-11-01

The production of endo- and exo-polygalacturonase (PG) by Aspergillus oryzae was assessed in stirred tank reactors (STRs), internal-loop airlift reactors (ILARs) and external-loop airlift reactors (ELARs). For STR production, we compared culture media formulated with either pectin (WBE) or partially hydrolyzed pectin. The highest enzyme activities were obtained in medium that contained 50% pectin in hydrolyzed form (WBE5). PG production in the three reactor types was compared for WBE5 and low salt WBE medium, with additional salts added at 48, 60 and 72h (WBES). The ELARs performed better than the ILARs in WBES medium where the exo-PG was the same concentration as for STRs and the endo-PG was 20% lower. These results indicate that PG production is higher under experimental conditions that result in higher cell growth with minimum pH values less than 3.0. Copyright © 2012 Elsevier Ltd. All rights reserved.

The impact of lemon pectin characteristics on TLR activation and T84 intestinal epithelial cell barrier function

NARCIS (Netherlands)

Vogt, Leonie M.; Sahasrabudhe, Neha M.; Ramasamy, Uttara; Meyer, Diederick; Pullens, Gerdie; Faas, Marijke M.; Venema, Koen; Schols, Henk A.; de Vos, Paul

Sufficient dietary fibre intake reduces the risk of several diseases, but the mechanisms linking fibre structure and health effects remain unclear. To analyse the influence of the amount of methyl groups esterified to the backbone, lemon pectins of different degrees of methyl esterification (30, 56,

The impact of lemon pectin characteristics on TLR activation and T84 intestinal epithelial cell barrier function

NARCIS (Netherlands)

Vogt, Leonie M.; Sahasrabudhe, Neha M.; Ramasamy, Uttara; Meyer, Diederick; Pullens, Gerdie; Faas, Marijke M.; Venema, Koen; Schols, Henk A.; Vos, de Paul

2016-01-01

Sufficient dietary fibre intake reduces the risk of several diseases, but the mechanisms linking fibre structure and health effects remain unclear. To analyse the influence of the amount of methyl groups esterified to the backbone, lemon pectins of different degrees of methyl esterification (30,

Progression of pectinate ligament dysplasia over time in two populations of Flat-Coated Retrievers.

Science.gov (United States)

Pearl, Rose; Gould, David; Spiess, Bernhard

2015-01-01

Two of the authors (DG, BS) independently observed that a number of Flat-Coated Retrievers (FCRs) previously unaffected by pectinate ligament dysplasia (PLD) appeared to develop the condition later in life. This study was instigated to investigate progression of PLD within individual dogs over time. Flat-Coated Retrievers that had previously undergone gonioscopy under the UK/ECVO hereditary eye schemes were included in the study. A second gonioscopic examination was performed 1.92-12.58 years later (mean 6, median 5.75 years) and the results compared. 39 FCR (17 males, 22 females) in the UK and 57 FCR (27 males, 30 females) in Switzerland were included. Slit-lamp biomicroscopy, indirect ophthalmoscopy, and gonioscopy were performed in all dogs. Gonioscopy allowed classification as either unaffected or affected; percentage of the iridocorneal drainage angle (ICA) affected by PLD was determined, before calculating progression observed as mild, moderate, or severe. 39 of 96 (40.6%) dogs demonstrated progression of PLD (P 90% ICA affected, consistent with a high risk of glaucoma. To the authors' knowledge, this is the first report describing progression of PLD in individual dogs over time, in a breed affected by primary, angle closure glaucoma. © 2013 American College of Veterinary Ophthalmologists.

Claviceps purpurea expressing polygalacturonases escaping PGIP inhibition fully infects PvPGIP2 wheat transgenic plants but its infection is delayed in wheat transgenic plants with increased level of pectin methyl esterification.

Science.gov (United States)

Volpi, Chiara; Raiola, Alessandro; Janni, Michela; Gordon, Anna; O'Sullivan, Donal M; Favaron, Francesco; D'Ovidio, Renato

2013-12-01

Claviceps purpurea is a biotrophic fungal pathogen of grasses causing the ergot disease. The infection process of C. purpurea on rye flowers is accompanied by pectin degradation and polygalacturonase (PG) activity represents a pathogenicity factor. Wheat is also infected by C. purpurea and we tested whether the presence of polygalacturonase inhibiting protein (PGIP) can affect pathogen infection and ergot disease development. Wheat transgenic plants expressing the bean PvPGIP2 did not show a clear reduction of disease symptoms when infected with C. purpurea. To ascertain the possible cause underlying this lack of improved resistance of PvPGIP2 plants, we expressed both polygalacturonases present in the C. purpurea genome, cppg1 and cppg2 in Pichia pastoris. In vitro assays using the heterologous expressed PGs and PvPGIP2 showed that neither PG is inhibited by this inhibitor. To further investigate the role of PG in the C. purpurea/wheat system, we demonstrated that the activity of both PGs of C. purpurea is reduced on highly methyl esterified pectin. Finally, we showed that this reduction in PG activity is relevant in planta, by inoculating with C. purpurea transgenic wheat plants overexpressing a pectin methyl esterase inhibitor (PMEI) and showing a high degree of pectin methyl esterification. We observed reduced disease symptoms in the transgenic line compared with null controls. Together, these results highlight the importance of pectin degradation for ergot disease development in wheat and sustain the notion that inhibition of pectin degradation may represent a possible route to control of ergot in cereals. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Identification and expression profiling of novel plant cell wall degrading enzymes from a destructive pest of palm trees, Rhynchophorus ferrugineus.

Science.gov (United States)

Antony, B; Johny, J; Aldosari, S A; Abdelazim, M M

2017-08-01

Plant cell wall degrading enzymes (PCWDEs) from insects were recently identified as a multigene family of proteins that consist primarily of glycoside hydrolases (GHs) and carbohydrate esterases (CEs) and play essential roles in the degradation of the cellulose/hemicellulose/pectin network in the invaded host plant. Here we applied transcriptomic and degenerate PCR approaches to identify the PCWDEs from a destructive pest of palm trees, Rhynchophorus ferrugineus, followed by a gut-specific and stage-specific differential expression analysis. We identified a total of 27 transcripts encoding GH family members and three transcripts of the CE family with cellulase, hemicellulase and pectinase activities. We also identified two GH9 candidates, which have not previously been reported from Curculionidae. The gut-specific quantitative expression analysis identified key cellulases, hemicellulases and pectinases from R. ferrugineus. The expression analysis revealed a pectin methylesterase, RferCE8u02, and a cellulase, GH45c34485, which showed the highest gut enriched expression. Comparison of PCWDE expression patterns revealed that cellulases and pectinases are significantly upregulated in the adult stages, and we observed specific high expression of the hemicellulase RferGH16c4170. Overall, our study revealed the potential of PCWDEs from R. ferrugineus, which may be useful in biotechnological applications and may represent new tools in R. ferrugineus pest management strategies. © 2017 The Royal Entomological Society.

OPTIMASI PROSES EKSTRAKSI PEKTIN DAMI BUAH NANGKA (Artocarpus heterophyllus Lamk Optimizing of Pectin Extraction Process from Jackfruit Rags (Artocarpus heterophyllus Lamk

Directory of Open Access Journals (Sweden)

I Nengah Kencana Putra

2012-05-01

Full Text Available The objective of this research was to determine the optimum  condition  on extraction process of jackfruit rags pectin. The experiment was designed by Randomized Block Design (RBD within 3 x 3 factorial experiment. The first factorwas pH of solvent consisted of 3 levels: 1.5, 2.5, and 3,5. The second factor was ratio of jackfruit rags to solvent, con-sisted of 3 levels: 1:5, 1:6 and 1:7. Results repealed that the solvent pH effected significantly yield, total ash, equivalentweigh and anhydrogalacturonic acid content of pectin produced. The optimum conditions for jackfruit rags pectin extraction were: the pH of extracting solvent was 1.5, and the ratio of jackfruit rags to solvent was 1:5. Those condi- tions gave the yield of 4.45 %, produced pectin having total ash (2.82 %, equivalent  weigh (3,022.24 g/eqi, methoxylcontent (8.16 %, and anhydrogalacturonic acid content (88.01 %. ABSTRAK Penelitian ini bertujuan untuk menentukan kondisi optimal pada proses ekstraksi pektin dami buah nangka. Rancanganpenelitian  yang digunakan adalah Rancangan Acak �elompok (RA� dengan pola percobaan faktorial  3 x 3. Faktorpertama adalah pH cairan pengekstrak yang terdiri dari 3 taraf: pH 1,5; 2,5 dan 3,5. Faktor kedua adalah perbandingandami buah nangka dengan cairan pengekstrak yang terdiri dari 3 taraf: 1:5, 1:6 dan 1:7. Hasil penelitian menunjukkan pH cairan pengekstrak berpengaruh nyata terhadap rendemen, kadar abu, berat ekivalen dan kadar asam anhidrogalak- turonat. Kondisi optimal untuk ekstraksi pektin dami buah nangka adalah: cairan pengekstrak pH 1,5, dengan perband- ingan dami nangka dan cairan pengekstrak 1:5. Kondisi ini menghasilkan rendemen 4,54 %, serta pektin dengan kara- kteristik: kadar abu 2,82 %, berat ekivalen 3.022,24 g/eki, kadar metoksil 8,16 % dan kadar asam anhidrogalakturonat88,01 %.

Jasmonate-dependent modifications of the pectin matrix during potato development function as a defense mechanism targeted by Dickeya dadantii virulence factors.

Science.gov (United States)

Taurino, Marco; Abelenda, Jose A; Río-Alvarez, Isabel; Navarro, Cristina; Vicedo, Begonya; Farmaki, Theodora; Jiménez, Pedro; García-Agustín, Pilar; López-Solanilla, Emilia; Prat, Salomé; Rojo, Enrique; Sánchez-Serrano, José J; Sanmartín, Maite

2014-02-01

The plant cell wall constitutes an essential protection barrier against pathogen attack. In addition, cell-wall disruption leads to accumulation of jasmonates (JAs), which are key signaling molecules for activation of plant inducible defense responses. However, whether JAs in return modulate the cell-wall composition to reinforce this defensive barrier remains unknown. The enzyme 13-allene oxide synthase (13-AOS) catalyzes the first committed step towards biosynthesis of JAs. In potato (Solanum tuberosum), there are two putative St13-AOS genes, which we show here to be differentially induced upon wounding. We also determine that both genes complement an Arabidopsis aos null mutant, indicating that they encode functional 13-AOS enzymes. Indeed, transgenic potato plants lacking both St13-AOS genes (CoAOS1/2 lines) exhibited a significant reduction of JAs, a concomitant decrease in wound-responsive gene activation, and an increased severity of soft rot disease symptoms caused by Dickeya dadantii. Intriguingly, a hypovirulent D. dadantii pel strain lacking the five major pectate lyases, which causes limited tissue maceration on wild-type plants, regained infectivity in CoAOS1/2 plants. In line with this, we found differences in pectin methyl esterase activity and cell-wall pectin composition between wild-type and CoAOS1/2 plants. Importantly, wild-type plants had pectins with a lower degree of methyl esterification, which are the substrates of the pectate lyases mutated in the pel strain. These results suggest that, during development of potato plants, JAs mediate modification of the pectin matrix to form a defensive barrier that is counteracted by pectinolytic virulence factors from D. dadantii. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

Low-methoxyl lemon pectin attenuates inflammatory responses and improves intestinal barrier integrity in caerulein-induced experimental acute pancreatitis

NARCIS (Netherlands)

Sun, Yajun; He, Yue; Wang, Fei; Zhang, Hao; de Vos, Paul; Sun, Jia

Scope: Acute pancreatitis (AP) is a common clinical acute abdominal disease. The intestinal injury associated with AP will aggravate the condition retroactively. This study investigates whether the low-methoxyl pectin (LMP) isolated from lemon could attenuate AP and associated intestinal injury.

Slowing the Starch Digestion by Structural Modification through Preparing Zein/Pectin Particle Stabilized Water-in-Water Emulsion.

Science.gov (United States)

Chen, Jia-Feng; Guo, Jian; Zhang, Tao; Wan, Zhi-Li; Yang, Juan; Yang, Xiao-Quan

2018-04-25

Slowing the digestion of starch is one of the dominant concerns in the food industry. A colloidal structural modification strategy for solving this problem was proposed in this work. Due to thermodynamic incompatibility between two biopolymers, water/water emulsion of waxy corn starch (WCS) droplets dispersed in a continuous aqueous guar gum (GG) was prepared, and zein particles (ZPs), obtained by antisolvent precipitation and pectin modification, were used as stabilizer. As the ratio of zein to pectin in the particles was 1:1, their wetting properties in the two polysaccharides were similar, which made them accumulate at the interface and cover the WCS-rich droplets. The analysis of digestibility curves indicated that a rapid (rate constant k 1 : 0.145 min -1 ) and a slow phase ( k 2 : 0.022 min -1 ) existed during WCS digestion. However, only one slow phase ( k 2 : 0.019 min -1 ) was found in the WCS/GG emulsion, suggesting that this structure was effective in slowing starch digestion.

The influence of tannin, pectin and polyethylene glycol on attachment of 15N-labelled rumen microorganisms to cellulose

International Nuclear Information System (INIS)

Bento, M.H.L.; Acamovic, T.; Makkar, H.P.S.

2005-01-01

The microbial attachment to and gas production from α-cellulose (Sigma; C-8002) without and with mimosa tannin (MT), pectin (P), polyethylene glycol (PEG), MT + P or MT + PEG, were investigated using the in vitro gas production system. Microbial attachment based on 15 N-labelled rumen microorganisms in the residual pellet after 24 h incubation was estimated, which varied from 113.7 to 161.3 μg 15 N per g residual pellet. C + MT had the lowest microbial attachment (P 2 = 0.84, P 15 N) in the residual pellet measured for C + MT (0.054) and C + MT + P (0.159), compared with the other treatments (0.32 for C; 0.34 for C + P; 0.33 for C + PEG; and 0.33 for C + MT + PEG). A MT concentration of 194 g/kg diet reduced microbial attachment and activity of rumen microorganisms in vitro. Polyethylene glycol counteracted the effect of MT on microbial attachment and activity. Pectin exerted a beneficial effect on attachment and fermentation in the initial hours of incubation. A ratio of pectin to MT of 1:1 improved microbial activity of C + MT but inhibition of microbial activity by MT remained at 24 h as indicated by the lower gas production of C + MT + P compared with the control. The results support the hypothesis that there is considerable interaction between tannins, microbes and non-starch-polysaccharides (NSP) in animal feeds and that these interactions may influence the functional ability of microbes in the gastrointestinal tract of animals. (author)

Pectins, ROS homeostasis and UV-B responses in plant roots.

Science.gov (United States)

Yokawa, Ken; Baluška, František

2015-04-01

Light from the sun contains far-red, visible and ultra violet (UV) wavelength regions. Almost all plant species have been evolved under the light environment. Interestingly, several photoreceptors, expressing both in shoots and roots, process the light information during the plant life cycle. Surprisingly, Arabidopsis root apices express besides the UVR8 UV-B receptor, also root-specific UV-B sensing proteins RUS1 and RUS2 linked to the polar cell-cell transport of auxin. In this mini-review, we focus on reactive oxygen species (ROS) signaling and possible roles of pectins internalized via endocytic vesicle recycling system in the root-specific UV-B perception and ROS homeostasis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Tocopherol deficiency reduces sucrose export from salt-stressed potato leaves independently of oxidative stress and symplastic obstruction by callose

Science.gov (United States)

Asensi-Fabado, María Amparo; Ammon, Alexandra; Sonnewald, Uwe; Munné-Bosch, Sergi; Voll, Lars M.

2015-01-01

Tocopherol cyclase, encoded by the gene SUCROSE EXPORT DEFECTIVE1, catalyses the second step in the synthesis of the antioxidant tocopherol. Depletion of SXD1 activity in maize and potato leaves leads to tocopherol deficiency and a ‘sugar export block’ phenotype that comprises massive starch accumulation and obstruction of plasmodesmata in paraveinal tissue by callose. We grew two transgenic StSXD1:RNAi potato lines with severe tocopherol deficiency under moderate light conditions and subjected them to salt stress. After three weeks of salt exposure, we observed a strongly reduced sugar exudation rate and a lack of starch mobilization in leaves of salt-stressed transgenic plants, but not in wild-type plants. However, callose accumulation in the vasculature declined upon salt stress in all genotypes, indicating that callose plugging of plasmodesmata was not the sole cause of the sugar export block phenotype in tocopherol-deficient leaves. Based on comprehensive gene expression analyses, we propose that enhanced responsiveness of SnRK1 target genes in mesophyll cells and altered redox regulation of phloem loading by SUT1 contribute to the attenuation of sucrose export from salt-stressed SXD:RNAi source leaves. Furthermore, we could not find any indication that elevated oxidative stress may have served as a trigger for the salt-induced carbohydrate phenotype of SXD1:RNAi transgenic plants. In leaves of the SXD1:RNAi plants, sodium accumulation was diminished, while proline accumulation and pools of soluble antioxidants were increased. As supported by phytohormone contents, these differences seem to increase longevity and prevent senescence of SXD:RNAi leaves under salt stress. PMID:25428995

Hydronium-dominated ion transport in carbon-dioxide-saturated electrolytes at low salt concentrations in nanochannels

DEFF Research Database (Denmark)

Lund Jensen, Kristian; Kristensen, Jesper Toft; Crumrine, Andrew Michael

2011-01-01

the nanochannel conductance at low salt concentrations and identify a conductance minimum before saturation at a value independent of salt concentration in the dilute limit. Via the Poisson-Boltzmann equation, our model self-consistently couples chemical-equilibrium dissociation models of the silica wall...

Chitosan-immobilized pectinolytics with novel catalytic features and fruit juice clarification potentialities.

Science.gov (United States)

Irshad, Muhammad; Murtza, Aimen; Zafar, Muddassar; Bhatti, Khizar Hayat; Rehman, Abdul; Anwar, Zahid

2017-11-01

Biological macromolecules are primarily composed of complex polysaccharides that strengthen microbial growth for the production of industrially relevant enzymes. The presence of polysaccharides in the form of the disrupted cell wall and cell materials are among major challenges in the fruit juice industry. The breakdown of such biological macromolecules including cellulose and pectin is vital for the juices processing. In this background, pectinolytic enzymes including polygalacturonase (PG), pectin lyase (PL), and pectin methylesterase (PME) were isolated from Aspergillus ornatus, statistically optimized and purified via ammonium sulfate fractionation (ASF), dialysis, and Sephadex G-100 gel permeation chromatography. After passing through Sephadex G-100 column, PG, PL, and PME were 2.60-fold, 3.30-fold, and 4.52-fold purified with specific activities of 475.2U/mg, 557.1U/mg, and 205.7U/mg. The active PG, PL, and PME, each separately, were surface immobilized using various concentrations of chitosan and dextran polyaldehyde as a macromolecular crosslinking agent. Prior to exploit for juice clarification purposes, various parameters including pH, thermal and Michaelis-Menten kinetic constants of purified and chitosan-immobilized fractions were investigated. A considerable improvement in the pH and thermal profiles was recorded after immobilization. However, the negligible difference between the K m and V max values of purified free and chitosan-immobilized fractions revealed that the conformational flexibility of pectinolytics was retained as such. A significant color and turbidity reductions were recorded after 60min treatment with CTS-PG, followed by CTS-PME, and CTS-PL. It can be concluded that the clarification of apples, mango, peach, and apricot juices was greatly affected by CTS-PG, CTS-PME, and CTS-PL treatments rendering them as potential candidatures for food industry applications. Copyright © 2017 Elsevier B.V. All rights reserved.

The output kinetics of piroxicam from emulsion microcapsules based on high methylated pectin and lactoglobulin of whey in experiments vitro

International Nuclear Information System (INIS)

Goibova, Z.V.; Bobokalonov, D.T.; Usmanova, S.R.; Teshaev, Kh.I.; Mukhidinov, Z.K.

2015-01-01

Present article is devoted to output kinetics of piroxicam from emulsion microcapsules based on high methylated pectin and lactoglobulin of whey in experiments vitro. The dependence of piroxicam output on time at various mole ratio was studied.

Surface adsorption behaviour of milk whey protein and pectin mixtures under conditions of air-water interface saturation.

Science.gov (United States)

Perez, Adrián A; Sánchez, Cecilio Carrera; Patino, Juan M Rodríguez; Rubiolo, Amelia C; Santiago, Liliana G

2011-07-01

Milk whey proteins (MWP) and pectins (Ps) are biopolymer ingredients commonly used in the manufacture of colloidal food products. Therefore, knowledge of the interfacial characteristics of these biopolymers and their mixtures is very important for the design of food dispersion formulations (foams and/or emulsions). In this paper, we examine the adsorption and surface dilatational behaviour of MWP/Ps systems under conditions in which biopolymers can saturate the air-water interface on their own. Experiments were performed at constant temperature (20 °C), pH 7 and ionic strength 0.05 M. Two MWP samples, β-lactoglobulin (β-LG) and whey protein concentrate (WPC), and two Ps samples, low-methoxyl pectin (LMP) and high-methoxyl pectin (HMP) were evaluated. The contribution of biopolymers (MWP and Ps) to the interfacial properties of mixed systems was evaluated on the basis of their individual surface molecular characteristics. Biopolymer bulk concentration capable of saturating the air-water interface was estimated from surface pressure isotherms. Under conditions of interfacial saturation, dynamic adsorption behaviour (surface pressure and dilatational rheological characteristics) of MWP/Ps systems was discussed from a kinetic point of view, in terms of molecular diffusion, penetration and configurational rearrangement at the air-water interface. The main adsorption mechanism in MWP/LMP mixtures might be the MWP interfacial segregation due to the thermodynamic incompatibility between MWP and LMP (synergistic mechanism); while the interfacial adsorption in MWP/HMP mixtures could be characterized by a competitive mechanism between MWP and HMP at the air-water interface (antagonistic mechanism). The magnitude of these phenomena could be closely related to differences in molecular composition and/or aggregation state of MWP (β-LG and WPC). Copyright © 2011 Elsevier B.V. All rights reserved.

Liking, salt taste perception and use of table salt when consuming reduced-salt chicken stews in light of South Africa's new salt regulations.

Science.gov (United States)

De Kock, H L; Zandstra, E H; Sayed, N; Wentzel-Viljoen, E

2016-01-01

This study investigated the impact of salt reduction on liking, salt taste perception, and use of table salt when consuming chicken stew in light of South Africa's new salt recommendations. In total, 432 South-African consumers (aged 35.2 ± 12.3 years) consumed a full portion of a chicken stew meal once at a central location. Four stock cube powders varying in salt content were used to prepare chicken stews: 1) no reduction - 2013 Na level; regular salt level as currently available on the South African market (24473 mg Na/100 g), 2) salt reduction smaller than 2016 level, i.e. 10%-reduced (22025 mg Na/100 g), 3) 2016 salt level, as per regulatory prescriptions (18000 mg Na/100 g), 4) 2019 salt level, as per regulatory prescriptions (13000 mg Na/100 g). Consumers were randomly allocated to consume one of the four meals. Liking, salt taste perception, and use of table salt and pepper were measured. Chicken stews prepared with reduced-salt stock powders were equally well-liked as chicken stews with the current salt level. Moreover, a gradual reduction of the salt in the chicken stews resulted in a reduced salt intake, up to an average of 19% for the total group compared to the benchmark 2013 Na level stew. However, 19% of consumers compensated by adding salt back to full compensation in some cases. More salt was added with increased reductions of salt in the meals, even to the point of full compensation. Further investigation into the impacts of nutrition communication and education about salt reduction on salt taste perception and use is needed. This research provides new consumer insights on salt use and emphasises the need for consumer-focused behaviour change approaches, in addition to reformulation of products. Copyright © 2015 Elsevier Ltd. All rights reserved.

Juice clarification by protease and pectinase treatments indicates new roles of pectin and protein in cherry juice turbidity

DEFF Research Database (Denmark)

Meyer, Anne S.; Zeuner, Birgitte; Pinelo-Jiménez, Manuel

2010-01-01

during cold storage (haze formation) is assumed to be due to protein–phenol interactions. Our results suggest that proteins play a decisive role in the formation of immediate turbidity in cherry juice, and point to that pectin may contribute to turbidity development during cold storage of cherry juice...

Development of High Throughput Salt Separation System with Integrated Liquid Salt Separation - Salt Distillation Assembly

Energy Technology Data Exchange (ETDEWEB)

Kwon, Sangwoon; Park, K. M.; Kim, J. G.; Jeong, J. H.; Lee, S. J.; Park, S. B.; Kim, S. S.

2013-01-15

The capacity of a salt distiller should be sufficiently large to reach the throughput of uranium electro-refining process. In this study, an assembly composing a liquid separation sieve and a distillation crucible was developed for the sequential operation of a liquid salt separation and a vacuum distillation in the same tower. The feasibility of the sequential salt separation was examined by the rotation test of the sieve-crucible assembly and sequential operation of a liquid salt separation and a vacuum distillation. The adhered salt in the uranium deposits was removed successfully. The salt content in the deposits was below 0.1 wt% after the sequential operation of the liquid salt separation - salt distillation. From the results of this study, it could be concluded that efficient salt separation can be realized by the sequential operation of liquid salt separation and vacuum distillation in one distillation tower since the operation procedures are simplified and no extra operation of cooling and reheating is necessary.

Sea Salt vs. Table Salt: What's the Difference?

Science.gov (United States)

... and healthy eating What's the difference between sea salt and table salt? Answers from Katherine Zeratsky, R.D., L.D. The main differences between sea salt and table salt are in their taste, texture ...

Phytochemical profiling of the ripening of Chinese mango (Mangifera indica L.) cultivars by real-time monitoring using UPLC-ESI-QTOF-MS and its potential benefits as prebiotic ingredients.

Science.gov (United States)

Hu, Kai; Dars, Abdul Ghani; Liu, Qiudou; Xie, Bijun; Sun, Zhida

2018-08-01

Maturity has important effects on the phytochemical and biochemical characteristics of fruits. It affects the quality, nutritional value, harvest time and commercial operations. In this study, Keitt, Sensation and Xiangya mango cultivars in four distinct stages from southwest China were evaluated for their phytochemical profiling and antioxidant activities in real time. Furthermore, the biochemical characteristics indices polyphenol oxidase (PPO), peroxidase (POD), superoxide dismutase (SOD) and pectin methylesterase (PME) activities were determined. Antioxidant compounds such as vitamin C, total phenolic, total flavonoid and total carotenoid content were also analysed. A total of 34 phenolic compounds were identified and quantitatively monitored by UPLC-ESI-QTOF-MS. Consecutive degradation of phenolic acids and its derivatives were observed upon maturity. We found that in addition to carotenoids, phenolic acids could also be used as a measurement index of maturity in mango. Mango juices and its phenolic extracts may be used as potential prebiotics for modulating probiotic proliferation. Copyright © 2018. Published by Elsevier Ltd.

Synthetic salt cake standards for analytical laboratory quality control

International Nuclear Information System (INIS)

Schilling, A.E.; Miller, A.G.

1980-01-01

The validation of analytical results in the characterization of Hanford Nuclear Defense Waste requires the preparation of synthetic waste for standard reference materials. Two independent synthetic salt cake standards have been prepared to monitor laboratory quality control for the chemical characterization of high-level salt cake and sludge waste in support of Rockwell Hanford Operations' High-Level Waste Management Program. Each synthetic salt cake standard contains 15 characterized chemical species and was subjected to an extensive verification/characterization program in two phases. Phase I consisted of an initial verification of each analyte in salt cake form in order to determine the current analytical capability for chemical analysis. Phase II consisted of a final characterization of those chemical species in solution form where conflicting verification data were observed. The 95 percent confidence interval on the mean for the following analytes within each standard is provided: sodium, nitrate, nitrite, phosphate, carbonate, sulfate, hydroxide, chromate, chloride, fluoride, aluminum, plutonium-239/240, strontium-90, cesium-137, and water

A new group of exo-acting family 28 glycoside hydrolases of Aspergillus niger that are involved in pectin degradation

NARCIS (Netherlands)

Martens-Uzunova, E.S.; Zandleven, J.S.; Benen, J.A.E.; Awad, H.; Kools, H.J.; Beldman, G.; Voragen, A.G.J.; Berg, van den J.A.; Schaap, P.J.

2006-01-01

The fungus Aspergillus niger is an industrial producer of pectin degrading enzymes. The recent solving of the genomic sequence of A. niger allowed an inventory of the entire genome of the fungus for potential carbohydrate degrading enzymes. By applying bioinformatics tools 12 new genes putatively

Mass transport in bedded salt and salt interbeds

International Nuclear Information System (INIS)

Hwang, Y.; Pigford, T.H.; Chambre, P.L.; Lee, W.W.L.

1989-08-01

Salt is the proposed host rock for geologic repositories of nuclear waste in several nations because it is nearly dry and probably impermeable. Although experiments and experience at potential salt sites indicate that salt may contain brine, the low porosity, creep, and permeability of salt make it still a good choice for geologic isolation. In this paper we summarize several mass-transfer and transport analyses of salt repositories. The mathematical details are given in our technical reports

Ionic diffusion and salt dissociation conditions of lithium liquid crystal electrolytes.

Science.gov (United States)

Saito, Yuria; Hirai, Kenichi; Murata, Shuuhei; Kishii, Yutaka; Kii, Keisuke; Yoshio, Masafumi; Kato, Takashi

2005-06-16

Salt dissociation conditions and dynamic properties of ionic species in liquid crystal electrolytes of lithium were investigated by a combination of NMR spectra and diffusion coefficient estimations using the pulsed gradient spin-echo NMR techniques. Activation energies of diffusion (Ea) of ionic species changed with the phase transition of the electrolyte. That is, Ea of the nematic phase was lower than that of the isotropic phase. This indicates that the aligned liquid crystal molecules prepared efficient conduction pathways for migration of ionic species. The dissociation degree of the salt was lower compared with those of the conventional electrolyte solutions and polymer gel electrolytes. This is attributed to the low concentration of polar sites, which attract the dissolved salt and promote salt dissociation, on the liquid crystal molecules. Furthermore, motional restriction of the molecules due to high viscosity and molecular oriented configuration in the nematic phase caused inefficient attraction of the sites for the salt. With a decreased dissolved salt concentration of the liquid crystal electrolyte, salt dissociation proceeded, and two diffusion components attributed to the ion and ion pair were detected independently. This means that the exchange rate between the ion and the ion pair is fairly slow once the salt is dissociated in the liquid crystal electrolytes due to the low motility of the medium molecules that initiate salt dissociation.

Casein Films: The Effects of Formulation, Environmental Conditions and the Addition of Citric Pectin on the Structure and Mechanical Properties

Directory of Open Access Journals (Sweden)

Laetitia M. Bonnaillie

2014-07-01

Full Text Available Thin casein films for food packaging applications reportedly possess good strength and low oxygen permeability, but low elasticity and high sensitivity to moisture. Modifying the films to target specific behaviors depending on environmental conditions can enable a variety of commercial applications for casein-based films. The mechanical properties of solvent-cast (15% solids calcium-caseinate/glycerol films (CaCas:Gly ratio of 3:1 were characterized as a function of processing and environmental conditions, including film thickness, solution formulation and ambient humidity (from 22% to 70% relative humidity (RH at ~20 °C. At constant RH, the elongation at break (EAB had a strong positive dependence on the film thickness. When RH increased, the tensile strength (TS and modulus (E decreased approximately linearly, while EAB increased. From 0.05% to 1% (w/w of citric pectin (CP was then incorporated into CaCas/Gly films following seven different formulations (mixing sequences, to alter the protein network and to evaluate the effects of CP on the tensile properties of CaCas/Gly/CP films. At constant film thickness and ~60% RH, the addition of 0.1% or 1.0% CP to the films considerably increased or decreased EAB, TS and E in different directions and to different extents, depending on the formulation, while optical micrographs also showed vastly differing network configurations, suggesting complex formulation- and stoichiometry-dependent casein-pectin interactions within the dried films. Depending on the desired film properties and utilization conditions, pectin may be a useful addition to casein film formulations for food packaging applications.

Novel pectin-silica hybrids used for immobilization of Trichosporon cutaneum cells efficient in removal of Cadmium and Copper ions from waste water

International Nuclear Information System (INIS)

Georgieva, N.; Rangelova, N.; Peshev, D.; Nenkova, S.

2011-01-01

New silica hybrid materials containing tetramethyl siloxane (TMOS) as an inorganic precursor and apple pectin (AP) as an organic compound were prepared. The quantity of organic substance was 5 and 50 wt% AP. The amorphous state of the samples was proved by X-ray diffraction analyses (XRD). The Infrared scattering spectra (IR) showed characteristic peaks for SiO2 network, as well as for pectin. The synthesized hybrid materials were applied as matrices for cells immobilization by attachment and entrapment of the filamentous yeast Trichosporon cutaneum R57. This strain showed considerable ability to remove cadmium and copper ions from aqueous solutions. Regarding heavy metal biosorption capacity, the attachment was found to be superior compared to the entrapment method as a technique for biomass immobilization. (authors) Key words: biomaterials, composite materials, microstructure, sol-gel preparation

Purification and general properties of pectin methyl esterase from Curvularia inaequalis NRRL 13884 in solid state culture using orange peels as an inducer.

Science.gov (United States)

Afifi, A F; Fawzi, E M; Foaad, M A

2002-01-01

Pectin methyl esterase (PME) [E.C.3. 1.1.11] production by Curvularia inaequalis (Shear) Boedijn NRRL 13884 was investigated using solid-state culture. The highest level of extracellular pectin methyl esterase was detected with orange peels as an inducing substrate and as a sole carbon source. The enzyme was partially purified using Sephadex G-100 and DEAE-Cellulose column chromatography. It was purified about 40 fold with optimum activity at pH 4.4 and 45 degrees C. The enzyme was activated by Co++, Mg++, Na+, whereas it was slightly activated in the presence of Cu++, K+, Mn++, Zn++. On the other hand Ag++, Ca++ and Hg++ inhibited the activity of the enzyme. The Km was calculated to be 0.52 mM.

21 CFR 100.155 - Salt and iodized salt.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Salt and iodized salt. 100.155 Section 100.155 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION GENERAL Specific Administrative Rulings and Decisions § 100.155 Salt and iodized salt. (a) For the purposes of this section, the...

Effects of Dietary Addition of a Low-Pectin Apple Fibre Preparation on Rats

Directory of Open Access Journals (Sweden)

Fotschki Bartosz

2014-09-01

Full Text Available The aim of this study was to scrutinise if the dietary addition of a low-pectin fibre preparation obtained from apple pomace, the by-product of apple concentrate processing, is able to favourably affect the gut metabolism, antioxidant status and blood bio-markers of the organism, as it takes place when apple fibre is present in the diet as an unprocessed ingredient. The nutritional experiment was performed on rats allocated to 2 groups of 10 animals each and fed for 2 weeks with either a control cellulose-containing diet or an experimental low-pectin apple fibre-containing diet. To induce metabolic disorders a diet rich in saturated fat and fructose was used in both diet-specific groups. The dietary apple fibre preparation (AFP significantly reduced the activity of sucrase and maltase in the mucosa of the small intestine. In the caecal digesta, the dietary AFP significantly increased bacterial α-glucosidase and α-galactosidase activity, whereas bacterial β-glucuronidase activity was significantly reduced. Also, the content of short chain fatty acids in the caecal digesta was significantly increased after the AFP supplementation. In the blood serum, the dietary AFP significantly reduced the glucose concentration, and decreased the ratio of total cholesterol to HDL cholesterol. In conclusion, the tested dietary AFP is still able to favourably affect the gut metabolism and can also ameliorate blood glucose concentration, which seems to be related to the inhibition of mucosal disaccharidase activities. However, the analysed preparation has no influence on the antioxidant status of the organism and may trigger adverse effects on cholesterol metabolism.

Investigation into the floating behaviour of a pectin-containing anti-reflux formulation by means of gamma scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Washington, N.; Wilson, C.G.; Greaves, J.L.; Danneskiold-Samsoee, P.

1988-01-01

The gastric distribution and residence time of a new pectin-containing formulation, FF5005 (Farma Food A/S, Denmark) was investigated by using the technique of gamma scintigraphy in six healthy volunteers after administration with a radiolabelled meal. The formulation and test meal were radiolabelled with indium-113m and technetium-99m, respectively, and the formulation was administered to the subjects 30 min after the labelled meal. FF5005 was shown to float and form a discrete phase on top of the stomach contents, and emptied from the stomach more slowly than the food (p<0.05, Wilcoxon signed rank test). The times taken for the formulation and test meal to half-empty from the stomach (T 5 0) were 4.13 +-0.69 h (mean +-SD) and 2.17 +-0.15 h (mean +-SD), respectively. More than 50% of the formulation remained in the fundal region of the stomach for 3 h. FF5005 produced in vivo behaviour similar to that of established alginate-containing anti-reflux agents, and the pectin content of the formulation was shown to decrease the rate of emptying of the meal.

New Edible Bionanocomposite Prepared by Pectin and Clove Essential Oil Nanoemulsions.

Science.gov (United States)

Sasaki, Ronaldo S; Mattoso, Luiz H C; de Moura, Márcia Regina

2016-06-01

Nanocomposites are being extremely investigated to provide packaging with interesting characteristics for packages. Because of essential oils' natural occurrence and antibacterial activity, they are considered as an alternative for synthetic additives in the food industry. In this paper, we studied an edible bionanocomposite film made up of pectin and clove essential oil nanoemulsion for application as edible package. Mechanical properties, water vapor permeability (WVP), and antibacterial activity were analyzed. From mechanical and WVP analyses, we noticed an interesting improvement in film properties. In the antibacterial activity test, disk diffusion was used to assess the inhibition zones of Escherichia coli and Staphylococcus aureus. With these results, we concluded that the most interesting results were promoted by smaller nanodroplets (diameter of approximately 142 nm).

Inhibition of Mammalian Target of Rapamycin Complex 1 Attenuates Salt-Induced Hypertension and Kidney Injury in Dahl Salt-Sensitive Rats.

Science.gov (United States)

Kumar, Vikash; Wollner, Clayton; Kurth, Theresa; Bukowy, John D; Cowley, Allen W

2017-10-01

The goal of the present study was to explore the protective effects of mTORC1 (mammalian target of rapamycin complex 1) inhibition by rapamycin on salt-induced hypertension and kidney injury in Dahl salt-sensitive (SS) rats. We have previously demonstrated that H 2 O 2 is elevated in the kidneys of SS rats. The present study showed a significant upregulation of renal mTORC1 activity in the SS rats fed a 4.0% NaCl for 3 days. In addition, renal interstitial infusion of H 2 O 2 into salt-resistant Sprague Dawley rats for 3 days was also found to stimulate mTORC1 activity independent of a rise of arterial blood pressure. Together, these data indicate that the salt-induced increases of renal H 2 O 2 in SS rats activated the mTORC1 pathway. Daily administration of rapamycin (IP, 1.5 mg/kg per day) for 21 days reduced salt-induced hypertension from 176.0±9.0 to 153.0±12.0 mm Hg in SS rats but had no effect on blood pressure salt sensitivity in Sprague Dawley treated rats. Compared with vehicle, rapamycin reduced albumin excretion rate in SS rats from 190.0±35.0 to 37.0±5.0 mg/d and reduced the renal infiltration of T lymphocytes (CD3 + ) and macrophages (ED1 + ) in the cortex and medulla. Renal hypertrophy and cell proliferation were also reduced in rapamycin-treated SS rats. We conclude that enhancement of intrarenal H 2 O 2 with a 4.0% NaCl diet stimulates the mTORC1 pathway that is necessary for the full development of the salt-induced hypertension and kidney injury in the SS rat. © 2017 American Heart Association, Inc.

Physical Characterization Of High Amylose/Pectin Mixtures Cross-Linked With Sodium Trimetaphosphate; Caracterizacao fisica de misturas alta amilose/pectina reticuladas com trimetafosfato de sodio

Energy Technology Data Exchange (ETDEWEB)

Carbinatto, F.M.; Cury, B.S.F.; Evangelista, R.C., E-mail: curybsf@fcfar.unesp.b [UNESP, Araraquara, SP (Brazil). Fac. de Ciencias Farmaceuticas

2010-07-01

Some researches have reported that pectin and high amylose mixtures presented superior mechanical properties in relation to those of the isolated polymers. In this work, mixtures at different ratios (1:4; 1:1) of pectin and high amylose were crosslinked with sodium trimetaphosphate at different degrees by varying reaction conditions. All samples were characterized by rheological and X-ray diffraction analyses. Samples without cross-linker were prepared as control. The oscillatory dynamic tests showed that all samples exhibited predominant elastic behavior, although cross-linked samples presented higher G' values, suggesting that crosslinking by phosphorylation resulted in more strength structures. The diffractograms showed that cross-linked samples underwent structural modifications that resulted in increase of crystallinity due to cross-linking process. (author)

A second pectin lyase gene (pel2) from Aspergillus oryzae KBN616: its sequence analysis and overexpression, and characterization of the gene products.

Science.gov (United States)

Kitamoto, N; Yoshino-Yasuda, S; Ohmiya, K; Tsukagoshi, N

2001-01-01

A second pectin lyase gene, designated pel2, was isolated from a shoyu koji mold Aspergillus oryzae KBN616 and characterized. The structural gene comprised 1306 bp with three introns. The ORF encoded 375 amino acids with a signal peptide of 19 amino acids. The deduced amino acid sequence showed high similarity to those of A. oryzae Pel1, Aspergillus niger pectin lyases and Glomerella cingulata Pn1A. The pel2 gene was overexpressed under the control of the promoter of the A. oryzae TEF1 gene for purification and enzymatic characterization of its gene product. The gene product exhibited two molecular masses of 48 and 44 kDa due to different degrees of glycosylation. Both proteins had the same pH optimum of 6.0 and temperature optimum of 50 degrees C.

Salt supply to and significance of asymmetric salt diapirs

DEFF Research Database (Denmark)

Koyi, H.; Burliga, S.; Chemia, Zurab

2012-01-01

Salt diapirs can be asymmetric both internally and externally reflecting their evolution history. As such, this asymmetry bear a significant amount of information about the differential loading (± lateral forces) and in turn the salt supply that have shaped the diapir. In two dimensions......, In this study we compare results of analogue and numerical models of diapirs with two natural salt diapris (Klodawa and Gorleben diapirs) to explain their salt supply and asymmetric evolution. In a NW-SE section, the Gorleben salt diapir possesses an asymmetric external geometry represented by a large...... southeastern overhang due to salt extrusion during Middle Cretaceous followed by its burial in Tertiary. This external asymmetry is also reflected in the internal configuration of the diapir which shows different rates of salt flow on the two halves of the structure. The asymmetric external and internal...

Antitumor Effect of Selenium and Modified Pectin Nano Particles and Gamma Radiation on Ehrilch Solid Tumor in Female Mice

International Nuclear Information System (INIS)

Mansour, S. Z.; Anis, L.M.; EI- Batal, A.I.

2010-01-01

Selenium nano particle (Nano- Se) is a novel Se species with novel biological activities with low toxicity. The aim of the present work was to evaluate the antitumor activity of a novel Nano- Se compound with or without gamma irradiation of female mice. Selenium size- controlled Nano-Se was prepared by a simple method by adding modified pectin to the selenious acid and ascorbic acid. The antitumor activity of Selenium and Modified Pectin Nano Particles (Se-Mp- NPs) were evaluated against Ehrilch ascites carcinoma (In vitro) and Ehrilch solid tumor model (In vivo). The antioxidant states of the novel compound were assessed measuring parameters in blood and tumor tissue of female mice. Malonaldehydoyl (MDA) end product of lipid peroxidation was evaluated in plasma and tumor tissue. Glutathione -S- transferase (GST) and cytochrome P450 (Cyto P450) were determined in tumor tissue homogenate. Tumor necrosis factor alpha (TNF- a) concentration and interleukin 10 (IL- 10) concentrations was evaluated in plasma of female mice. The effect of tumor inoculation and different treatments on liver enzymes (ALT and AST) and kidney Function (urea and creatinine) were detected in the plasma of animals. Apoptosis was shown and estimated in tumor tissue of animals histopathological of tumor in different groups of mice were examined. Ehrilch solid tumor induced a significant increase in MDA content, GSH-Px and GST activities level and in the amount of metabolites of CYP 450. Moreover, a significant decrease was observed in GSH content, SOD activity level in the tumor tissue, INF- a concentration, IL- 10 concentration in the plasma. Also, a significant alteration in kidney and liver functions was occurred as compared to control group. The results showed a significant antitumor activity of selenium and Modified Pectin Nano Particles (Se-Mp- NPs) at the concentration 2.25 μg / ml was 70%

Salt-assisted and salt-suppressed sol-gel transitions of methylcellulose in water.

Science.gov (United States)

Xu, Y; Wang, C; Tam, K C; Li, L

2004-02-03

The effects of various salts on the sol-gel transition of aqueous methylcellulose (MC) solutions have been studied systematically by means of a micro differential scanning calorimeter. It was found that the heating process was endothermic while the cooling process was exothermic for both MC solutions with and without salts. The addition of salts did not change the patterns of gelation and degelation of MC. However, the salts could shift the sol-gel transition and the gel-sol transition to lower or higher temperatures from a pure MC solution, depending on the salt type. These opposite effects were termed the salt-assisted and salt-suppressed sol-gel transitions. Either the salt-assisted transition or the salt-suppressed sol-gel transition was a function of salt concentration. In addition, each salt was found to have its own concentration limit for producing a stable aqueous solution of MC at a given concentration of MC, which was related to the anionic charge density of the salt. Cations were proved to have weaker effects than anions. The "salt-out strength", defined as the salt effect per mole of anion, was obtained for each anion studied. The thermodynamic mechanisms involved in the salt-assisted and salt-suppressed sol-gel transitions are discussed.

An investigation into the floating behaviour of a pectin-containing anti-reflux formulation by means of gamma scintigraphy

International Nuclear Information System (INIS)

Washington, N.; Wilson, C.G.; Greaves, J.L.; Danneskiold-Samsoee, P.

1988-01-01

The gastric distribution and residence time of a new pectin-containing formulation, FF5005 (Farma Food A/S, Denmark) was investigated by using the technique of gamma scintigraphy in six healthy volunteers after administration with a radiolabelled meal. The formulation and test meal were radiolabelled with indium-113m and technetium-99m, respectively, and the formulation was administered to the subjects 30 min after the labelled meal. FF5005 was shown to float and form a discrete phase on top of the stomach contents, and emptied from the stomach more slowly than the food (p<0.05, Wilcoxon signed rank test). The times taken for the formulation and test meal to half-empty from the stomach (T 5 0) were 4.13 ±0.69 h (mean ±SD) and 2.17 ±0.15 h (mean ±SD), respectively. More than 50% of the formulation remained in the fundal region of the stomach for 3 h. FF5005 produced in vivo behaviour similar to that of established alginate-containing anti-reflux agents, and the pectin content of the formulation was shown to decrease the rate of emptying of the meal

Modulation of the adsorption properties at air-water interfaces of complexes of egg white ovalbumin with pectin by the dielectric constant

NARCIS (Netherlands)

Kudryashova, E.V.; Jongh, H.H.J.de

2008-01-01

The possibility of modulating the mesoscopic properties of food colloidal systems by the dielectric constant is studied by determining the impact of small amounts of ethanol (10%) on the adsorption of egg white ovalbumin onto the air-water interface in the absence and presence of pectin. The

Location-independent study concerning the construction, operation and closure of possible facilities for the final storage of radioactive waste in rock-salt formations in the Netherlands

International Nuclear Information System (INIS)

1986-04-01

Final storage of radioactive waste has been studied on the base of two main concepts: in deep boreholes and caverns from the mowing-field, and for a, for this purpose to be developed, underground ore. Storage supplies have been designed, including the closing constructions after finishing the storage activities, with a, much longer than usually, technical lifetime. Herein use has been made of in general known materials whose properties and behaviour were assumed to remain unaltered over long periods and also will not be influenced by the rock-salt environment. The possible storage concepts described are location independent and based upon the geological and geomechanical information which have been provided with the task and which are indicative for the rock-salt formations occurring in the Netherlands. In first instance the authors have started from the thermodynamical, chemical and fysical properties of the storage rock-formations as are mentioned in the apendices of the task. It particularly concerns properties of the storage rock-formations and the construction materials needed for a qualitatively good and reliable closing of the storage. The construction and operation of the in this report described storage concepts is based upon the storage scenario's as indicated in the task circumscriptions

Where Does Road Salt Go - a Static Salt Model

Science.gov (United States)

Yu, C. W.; Liu, F.; Moriarty, V. W.

2017-12-01

Each winter, more than 15 million tons of road salt is applied in the United States for the de-icing purpose. Considerable amount of chloride in road salt flows into streams/drainage systems with the snow melt runoff and spring storms, and eventually goes into ecologically sensitive low-lying areas in the watershed, such as ponds and lakes. In many watersheds in the northern part of US, the chloride level in the water body has increased significantly in the past decades, and continues an upward trend. The environmental and ecological impact of the elevated chloride level can no longer be ignored. However although there are many studies on the biological impact of elevated chloride levels, there are few investigations on how the spatially distributed road salt application affects various parts of the watershed. In this presentation, we propose a static road salt model as a first-order metric to address spacial distribution of salt loading. Derived from the Topological Wetness Index (TWI) in many hydrological models, this static salt model provides a spatial impact as- sessment of road salt applications. To demonstrate the effectiveness of the static model, National Elevation Dataset (NED) of ten-meter resolution of Lake George watershed in New York State is used to generate the TWI, which is used to compute a spatially dis- tributed "salt-loading coefficient" of the whole watershed. Spatially varying salt applica- tion rate is then aggregated, using the salt-loading coefficients as weights, to provide salt loading assessments of streams in the watershed. Time-aggregated data from five CTD (conductivity-temperature-depth) sensors in selected streams are used for calibration. The model outputs and the sensor data demonstrate a strong linear correlation, with the R value of 0.97. The investigation shows that the static modeling approach may provide an effective method for the understanding the input and transport of road salt to within watersheds.

Ultrasound assisted extraction of pectin from waste Artocarpus heterophyllus fruit peel.

Science.gov (United States)

Moorthy, I Ganesh; Maran, J Prakash; Ilakya, S; Anitha, S L; Sabarima, S Pooja; Priya, B

2017-01-01

Four factors three level face centered central composite response surface design was employed in this study to investigate and optimize the effect of process variables (liquid-solid (LS) ratio (10:1-20:1ml/g), pH (1-2), sonication time (15-30min) and extraction temperature (50-70°C)) on the maximum extraction yield of pectin from waste Artocarpus heterophyllus (Jackfruit) peel by ultrasound assisted extraction method. Numerical optimization method was adapted in this study and the following optimal condition was obtained as follows: Liquid-solid ratio of 15:1ml/g, pH of 1.6, sonication time of 24min and temperature of 60°C. The optimal condition was validated through experiments and the observed value was interrelated with predicted value. Copyright © 2016 Elsevier B.V. All rights reserved.

Pectin nanocoating of titanium implant surfaces - an experimental study in rabbits

DEFF Research Database (Denmark)

Gurzawska, Katarzyna Aleksandra; Dirscherl, Kai; Jørgensen, Bodil

2017-01-01

that may increase adhesion of bone proteins, and bone cells at the implant surface. Nanocoating with pectins, plant cell wall-derived polysaccharides, is frequently done using rhamnogalacturonan-I (RG-I). AIM: The aim of the study was to evaluate the effect of nanocoating titanium implants with plant cell...... wall-derived rhamnogalacturonan-I, on bone healing and osseointegration. MATERIAL AND METHODS: Machined titanium implants were coated with three modifications of rhamnogalacturonan-I (RG-I). Chemical and physical surface properties were examined before insertion of nanocoated implants (n = 96....... The bone response to the nanocoated implants was analyzed qualitatively and quantitatively after 2, 4, 6, and 8 weeks of healing using light microscopy and histomorphometric methods. RESULTS: The RG-I coating influenced the surface chemical composition; wettability and roughness, making the surface more...

An increase in pectin methyl esterase activity accompanies dormancy breakage and germination of yellow cedar seeds.

Science.gov (United States)

Ren, C; Kermode, A R

2000-09-01

Pectin methyl esterase (PME) (EC 3.1.1.11) catalyzes the hydrolysis of methylester groups of cell wall pectins. We investigated the role of this enzyme in dormancy termination and germination of yellow cedar (Chamaecyparis nootkatensis [D. Don] Spach) seeds. PME activity was not detected in dormant seeds of yellow cedar but was induced and gradually increased during moist chilling; high activity coincided with dormancy breakage and germination. PME activity was positively correlated to the degree of dormancy breakage of yellow cedar seeds. The enzyme produced in different seed parts and in seeds at different times during moist chilling, germination, and early post-germinative growth consisted of two isoforms, both basic with isoelectric points of 8.7 and 8.9 and the same molecular mass of 62 kD. The pH optimum for the enzyme was between 7.4 and 8.4. In intact yellow cedar seeds, activities of the two basic isoforms of PME that were induced in embryos and in megagametophytes following dormancy breakage were significantly suppressed by abscisic acid. Gibberellic acid had a stimulatory effect on the activities of these isoforms in embryos and megagametophytes of intact seeds at the germinative stage. We hypothesize that PME plays a role in weakening of the megagametophyte, allowing radicle emergence and the completion of germination.

Molten salt fueled reactors with a fast salt draining

International Nuclear Information System (INIS)

Ventre, Edmond; Blum, J.M.

1976-01-01

This invention relates to a molten salt nuclear reactor which comprises a new arrangement for shutting it down in complete safety. This nuclear reactor has a molten salt primary circuit comprising, in particular, the core of this reactor. It includes a leak tight vessel the capacity of which is appreciably greater than that of the molten salt volume of the circuit and placed so that the level of the molten salt, when all the molten salt of the circuit is contained in this vessel, is less than that of the base of the core. There are facilities for establishing and maintaining an inert gas pressure in the vessel above the molten salt, for releasing the compressed gas and for connecting the vessel to the primary circuit entering this vessel at a lower level than that of the molten salt and enabling molten salt to enter or leave the vessel according to the pressure of the inert gas. The particular advantage of this reactor is that it can be shut down safely since the draining of the primary circuit no longer results from a 'positive action' but from the suppression of an arrangement essential for the operation of the reactor consisting of the build-up of the said inert gas pressure in the said vessel [fr

Molten salt oxidation of organic hazardous waste with high salt content.

Science.gov (United States)

Lin, Chengqian; Chi, Yong; Jin, Yuqi; Jiang, Xuguang; Buekens, Alfons; Zhang, Qi; Chen, Jian

2018-02-01

Organic hazardous waste often contains some salt, owing to the widespread use of alkali salts during industrial manufacturing processes. These salts cause complications during the treatment of this type of waste. Molten salt oxidation is a flameless, robust thermal process, with inherent capability of destroying the organic constituents of wastes, while retaining the inorganic ingredients in the molten salt. In the present study, molten salt oxidation is employed for treating a typical organic hazardous waste with a high content of alkali salts. The hazardous waste derives from the production of thiotriazinone. Molten salt oxidation experiments have been conducted using a lab-scale molten salt oxidation reactor, and the emissions of CO, NO, SO 2 , HCl and dioxins are studied. Impacts are investigated from the composition of the molten salts, the types of feeding tube, the temperature of molten carbonates and the air factor. Results show that the waste can be oxidised effectively in a molten salt bath. Temperature of molten carbonates plays the most important role. With the temperature rising from 600 °C to 750 °C, the oxidation efficiency increases from 91.1% to 98.3%. Compared with the temperature, air factor has but a minor effect, as well as the composition of the molten salts and the type of feeding tube. The molten carbonates retain chlorine with an efficiency higher than 99.9% and the emissions of dioxins are below 8 pg TEQ g -1 sample. The present study shows that molten salt oxidation is a promising alternative for the disposal of organic hazardous wastes containing a high salt content.

Salt effect on sensitized photooxidations. A kinetic approch to environmental decomposition of marine contaminants

Directory of Open Access Journals (Sweden)

María I. Gutiérrez

1998-09-01

Full Text Available The salt effect on the kinetics of singlet molecular oxygen [O2(1Δg]-mediated photooxidations of sea water contaminants was investigated. Two families of photooxidizable compounds were employed in the study: anthracene derivatives and phenols. The presence of salt (NaCl in H2O and LiCl in MeCN, in both cases in the range 0-0.45 M produces changes in the photooxidation rate. For solvent-polarity-dependent reactions, this behavior can be predicted, by knowing the solvent-polarity dependence of the rate constant for chemical reaction of the substrates with O2(1Δ g in non-saline solutions (kr. For the cases of photooxidations possessing solvent-polarity-independent or scantily-dependent kr values, the photooxidation rates decrease as the salt content in the solution increases, mainly due to a predominance of the physical quenching pathway. In addition, the quantum yield for O2(1 Δg generation (ΦΔ was determined in a series of saline solutions, in the range of 0-0.45 M in water and MeCN solutions, in the presence of NaCl and LiCl respectively. The Δ values are independent, within the experimental error on the salt content.

Effects of in vitro fermentation of barley β-glucan and sugar beet pectin using human fecal inocula on cytokine expression by dendritic cells

NARCIS (Netherlands)

Rosch, Christiane; Taverne, Nico; Venema, Koen; Gruppen, Harry; Wells, Jerry M.; Schols, Henk A.

2017-01-01

Scope: This study simulates the fermentation process of barley β-glucan and sugar beet pectin in the human colon and monitors the degradation products formed. Additionally, immune effects of the degradation products were investigated. Methods and results: Immunostimulatory activity of

Salt Composition Derived from Veazey Composition by Thermodynamic Modeling and Predicted Composition of Drum Contents

Energy Technology Data Exchange (ETDEWEB)

Weisbrod, Kirk Ryan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Veirs, Douglas Kirk [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Funk, David John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Clark, David Lewis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-03-11

This report describes the derivation of the salt composition from the Veazey salt stream analysis. It also provides an estimate of the proportions of the kitty litter, nitrate salt and neutralizer that was contained in drum 68660. While the actinide content of waste streams was judiciously followed in the 1980s in TA-55, no record of the salt composition could be found. Consequently, a salt waste stream produced from 1992 to 1994 and reported by Gerry Veazey provided the basis for this study. While chemical analysis of the waste stream was highly variable, an average analysis provided input to the Stream Analyzer software to calculate a composition for a concentrated solid nitrate salt and liquid waste stream. The calculation predicted the gas / condensed phase compositions as well as solid salt / saturated liquid compositions. The derived composition provides an estimate of the nitrate feedstream to WIPP for which kinetic measurements can be made. The ratio of salt to Swheat in drum 68660 contents was estimated through an overall mass balance on the parent and sibling drums. The RTR video provided independent confirmation concerning the volume of the mixture. The solid salt layer contains the majority of the salt at a ratio with Swheat that potentially could become exothermic.

Salt Composition Derived from Veazey Composition by Thermodynamic Modeling and Predicted Composition of Drum Contents

International Nuclear Information System (INIS)

Weisbrod, Kirk Ryan; Veirs, Douglas Kirk; Funk, David John; Clark, David Lewis

2016-01-01

This report describes the derivation of the salt composition from the Veazey salt stream analysis. It also provides an estimate of the proportions of the kitty litter, nitrate salt and neutralizer that was contained in drum 68660. While the actinide content of waste streams was judiciously followed in the 1980s in TA-55, no record of the salt composition could be found. Consequently, a salt waste stream produced from 1992 to 1994 and reported by Gerry Veazey provided the basis for this study. While chemical analysis of the waste stream was highly variable, an average analysis provided input to the Stream Analyzer software to calculate a composition for a concentrated solid nitrate salt and liquid waste stream. The calculation predicted the gas / condensed phase compositions as well as solid salt / saturated liquid compositions. The derived composition provides an estimate of the nitrate feedstream to WIPP for which kinetic measurements can be made. The ratio of salt to Swheat in drum 68660 contents was estimated through an overall mass balance on the parent and sibling drums. The RTR video provided independent confirmation concerning the volume of the mixture. The solid salt layer contains the majority of the salt at a ratio with Swheat that potentially could become exothermic.

Constant Electric and Magnetic Fields Effect on the Structuring and Thermomechanical and Thermophysical Properties of Nanocomposites Formed from Pectin-Cu(2+)-Polyethyleneimine Interpolyelectrolyte-Metal Complexes.

Science.gov (United States)

Demchenko, V; Shtompel', V; Riabov, S; Lysenkov, E

2015-12-01

Applying wide-angle X-ray scattering method, thermomechanical analysis, and differential scanning calorimetry, the structural organization and properties of nanocomposites formed by chemical reduction of Сu(2+) cations in the interpolyelectrolyte-metal complex (pectin-Cu(2+)-polyethyleneimine) under the influence of a constant magnetic and electric fields have been studied. It has been found that the chemical reduction of Cu(2+) cations in the interpolyelectrolyte-metal complex bulk under constant electric and magnetic fields leads to formation of nanocomposite consisting of interpolyelectrolyte complex, including pectin-polyethyleneimine and nanoparticles of the metal Cu phase, whereas nanocomposite with Cu/Cu2O nanoparticles is formed in original state (without any field). It was observed that, under constant field, nanocomposites obtained have higher structural glass-transition temperatures and thermal stability.

The pectinases from Sphenophorus levis: Potential for biotechnological applications.

Science.gov (United States)

Habrylo, Olivier; Evangelista, Danilo Elton; Castilho, Priscila Vasques; Pelloux, Jérôme; Henrique-Silva, Flávio

2018-06-01

Pectinases represent about one fifth of the enzyme worldwide market due their wide range of biotechnological applications. Current commercial pectinases are exclusively obtained from microbial sources, but here we report a pectin methylesterase (Sl-PME) and an endo-polygalacturonase (Sl-EPG) bioprospected from the sugarcane weevil, Sphenophorus levis, which revealed good potential for industrial applications. Sl-PME and Sl-EPG were overexpressed in Pichia pastoris, purified and enzymatically characterized. Sl-EPG presents optimal activity at pH 4-5 and 50 °C, showing that it can be used for juice extraction and clarification. On the other hand, Sl-PME presents optimal activity at pH 6-8 and 40 °C, and thus, suitable for both acidic and alkaline processing, such as coffee and tea fermentation. Sl-EPG shows V max  = 3.23 mM/min, K M  = 2.4 g/L and k cat  = 418.6 s -1 . While Sl-PME shows V max  = 0.14 mM/min, K M  = 4.1 g/L and k cat  = 1.7 s -1 . A PG inhibitor (PGIP2) weakly interfered in the Sl-EPG activity and Sl-PME was not affected by a usual PME inhibitor. Moreover, these enzymes manifested synergistic action towards methylesterified pectin. Here, we propose these enzymes as novel alternative tools for the current commercial pectinases. Copyright © 2018 Elsevier B.V. All rights reserved.

Identification of a single sinusoidal bile salt uptake system in skate liver

International Nuclear Information System (INIS)

Fricker, G.; Hugentobler, G.; Meier, P.J.; Kurz, G.; Boyer, J.L.

1987-01-01

To identify the sinusoidal bile acid uptake system(s) of skate liver, photoaffinity labeling and kinetic transport studies were performed in isolated plasma membranes as well as intact hepatocytes. In both preparations photoaffinity labeling with the photolabile bile salt derivative revealed the presence of a predominant bile salt binding polypeptide with an apparent molecular weight of 54,000. The [ 3 H]-labeling of this polypeptide was inhibited by taurocholate and cholate in a concentration-dependent manner and was virtually abolished by 1 mM of the anion transport inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid. Kinetic studies of hepatic uptake with taurocholate, cholate, and the photoreactive bile salt derivative indicated the involvement of a single transport system, and all three substrates mutually competed with the uptake of each other. Finally, irreversible inhibition of the bile salt uptake system of photoaffinity labeling of hepatocytes with high concentrations of photolabile derivative reduced the V max but the K m of taurocholate uptake. These findings strongly indicate that a single polypeptide with an apparent molecular weight of 54,000 is involved in sinusoidal bile salt uptake into skate hepatocytes. These findings contrast with similar studies in rat liver that implicate both a 54,000- and 48,000-K polypeptide in bile salt uptake and are consistent with a single Na + -independent transport mechanism for hepatic bile salt uptake in this primitive vertebrate

Ozone fumigation for safety and quality of wine grapes in postharvest dehydration.

Science.gov (United States)

Botondi, Rinaldo; De Sanctis, Federica; Moscatelli, Niccolò; Vettraino, Anna Maria; Catelli, Cesare; Mencarelli, Fabio

2015-12-01

This paper proposes postharvest ozone fumigation (as a method) to control microorganisms and evaluate the effect on polyphenols, anthocyanins, carotenoids and cell wall enzymes during the grape dehydration for wine production. Pignola grapes were ozone-treated (1.5 g/h) for 18 h (A=shock treatment), then dehydrated or ozone-treated (1.5 g/h) for 18 h and at 0.5 g/h for 4 h each day (B=long-term treatment) during dehydration. Treatment and dehydration were performed at 10 °C. No significant difference was found for total carotenoid, total phenolic and total anthocyanin contents after 18 h of O3 treatment. A significant decrease in phenolic and anthocyanin contents occurred during treatment B. Also carotenoids were affected by B ozone treatment. Pectin methylesterase (PME) and polygalacturonase (PG) activities were higher in A-treated grapes during dehydration. Finally, ozone reduced fungi and yeasts by 50%. Shock ozone fumigation (A treatment) before dehydration can be used to reduce the microbial count during dehydration without affecting polyphenol and carotenoid contents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of sodium chloride on the growth and fruiting of Cabernet Sauvignon vines

Energy Technology Data Exchange (ETDEWEB)

Hawker, J.S.; Walker, R.R.

1978-01-01

Sodium chloride was supplied to rooted cuttings of Vitis vinifera cv Cabernet Sauvignon grown in a porous growth medium at concentrations of 0, 20, 50 and 75 mM. Shoot and leaf growth and berry set and development were reduced by NaCl, the severity of the effects depending on both NaCl concentration and the age of the plants receiving the treatment. Shoots were not affected by 20 mM NaCl supplied 10 days after flowering but 50 and 75 mM NaCl caused severe stunting of shoots and 75 mM NaCl had a marked effect on berry growth and development. When NaCl was supplied to vines 10 days before flowering, 20, 50 and 75 mM NaCl inhibited shoot growth and reduced berry size and sugar content. Although NaCl caused a decrease in the rate of growth of both leaves and berries, no changes in invertase or pectin methylesterase activities were found in these organs from plants supplied with NaCl.

Effect of high hydrostatic pressure on overall quality parameters of watermelon juice.