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Sample records for chrysanthemi pectin methylesterase

  1. 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

    Pectin methylesterases (PMEs) catalyse the removal of methyl esters from the homogalacturonan (HG) backbone domain of pectin, a ubiquitous polysaccharide in plant cell walls. The degree of methyl esterification (DE) impacts upon the functional properties of HG within cell walls and plants produce...... numerous PMEs that act upon HG in muro. Many microbial plant pathogens also produce PMEs, the activity of which renders HG more susceptible to cleavage by pectin lyase and polygalacturonase enzymes and hence aids cell wall degradation. We have developed a novel microarray-based approach to investigate...... 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...

  2. Roles of Pectin Methylesterases in Pollen-Tube Growth

    Institute of Scientific and Technical Information of China (English)

    Li-Qun Chen; De Ye

    2007-01-01

    Elongation of the pollen tube in pistil is essential for delivering sperms into the female gametophyte in sexual plant reproduction. Recently, a group of cell wall enzymes, pectin methylesterases (PMEs), have been identified as playing an important role in this process. This article reviews the new understanding of the roles of PMEs in regulating pollen tube growth.

  3. Mode of action of Bacillus licheniformis pectin methylesterase on highly methylesterified and acetylated pectins

    NARCIS (Netherlands)

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

    2015-01-01

    A gene encoding a putative pectinesterase from Bacillus licheniformis DSM13 was cloned and expressed in Escherichia coli. The resulting recombinant enzyme (BliPME) was purified and characterized as a pectin methylesterase. The enzyme showed maximum activity at pH 8.0 and 50 °C. BliPME is able to rel

  4. Functional characterization of the gels prepared with pectin methylesterase (PME)-treated pectins.

    Science.gov (United States)

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

    2009-10-01

    High- and low-methoxyl pectins were treated with pectin methylesterase (PME) and the functional properties of the resulting pectin gels were characterized. The degree of esterification of high- and low-methoxyl pectins decreased from 74.5% to 6.3% and 40.0% to 6.5%, respectively while not changing their molecular weight. Also, the addition of glucono-delta-lactone (GDL) dramatically affected the gel strength and the pH reduction by the GDL led to the increased syneresis of the pectin gels, which was also observed in the PME-treated samples. When flavor compounds were incorporated into the pectin gels, the flavor release from the gels increased with decreasing the degree of esterification due to increased hydrophilic properties.

  5. Effect of pectin methylesterase gene expression on pea root development.

    Science.gov (United States)

    Wen, F; Zhu, Y; Hawes, M C

    1999-06-01

    Expression of an inducible gene with sequences common to genes encoding pectin methylesterase (PME) was found to be tightly correlated, both spatially and temporally, with border cell separation in pea root caps. Partial inhibition of the gene's expression by antisense mRNA in transgenic pea hairy roots prevented the normal separation of root border cells from the root tip into the external environment. This phenotype was correlated with an increase in extracellular pH, reduced root elongation, and altered cellular morphology. The translation product of the gene exhibited PME activity in vitro. These results are consistent with the long-standing hypothesis that the demethylation of pectin by PME plays a key role in cell wall metabolism.

  6. Thermal inactivation kinetics of partially purified mango pectin methylesterase

    Directory of Open Access Journals (Sweden)

    Claudio Alonso DÍAZ-CRUZ

    2016-01-01

    Full Text Available Abstract Kinetic parameters of thermal inactivation of pectin methylesterase (PME in a partially purified mango enzyme extract were determined. The PME of mango partially purified by salting out showed different patterns of thermal inactivation, indicating the presence of a thermostable fraction at 70 °C and a thermolabile fraction at lower temperatures. The inactivation of the thermostable fraction exhibited a linear behavior that yielded a z-value of 9.44 °C and an activation energy (Ea of 245.6 kJ mol-1 K-1 using the Arrhenius model. The thermostable mango PME fraction represented 17% of total crude enzyme extract, which emphasizes the importance of residual enzyme activity after heat treatment.

  7. Effect of silencing the two major tomato fruit pectin methylesterase isoforms on cell wall pectin metabolism.

    Science.gov (United States)

    Wen, B; Ström, A; Tasker, A; West, G; Tucker, G A

    2013-11-01

    Post-harvest storage is largely limited by fruit softening, a result of cell wall degradation. Pectin methylesterase (PE) (EC 3.1.1.11) is a major hydrolase responsible for pectin de-esterification in the cell wall, a response to fruit ripening. Two major PE isoforms, PE1 and PE2, have been isolated from tomato (Solanum lycopersicon) pericarp tissue and both have previously been down-regulated using antisense suppression. In this paper, PE1 and PE2 double antisense tomato plants were successfully generated through crossing the two single antisense lines. In the double antisense fruit, approximately 10% of normal PE activity remained and ripening associated pectin de-esterification was almost completely blocked. However, double antisense fruit softened normally during ripening. In tomato fruit, the PE1 isoform was found to contribute little to total PE activity and have little effect on the degree of esterification of pectin. In contrast, the other dominant fruit isoform, PE2, has a major impact on de-esterification of total pectin. PE2 appears to act on non-CDTA-soluble pectin during ripening and on CDTA-soluble pectin before the start of ripening in a potentially block-wise fashion.

  8. Arabidopsis PECTIN METHYLESTERASEs contribute to immunity against Pseudomonas syringae.

    Science.gov (United States)

    Bethke, Gerit; Grundman, Rachael E; Sreekanta, Suma; Truman, William; Katagiri, Fumiaki; Glazebrook, Jane

    2014-02-01

    Pectins, major components of dicot cell walls, are synthesized in a heavily methylesterified form in the Golgi and are partially deesterified by pectin methylesterases (PMEs) upon export to the cell wall. PME activity is important for the virulence of the necrotrophic fungal pathogen Botrytis cinerea. Here, the roles of Arabidopsis PMEs in pattern-triggered immunity and immune responses to the necrotrophic fungus Alternaria brassicicola and the bacterial hemibiotroph Pseudomonas syringae pv maculicola ES4326 (Pma ES4326) were studied. Plant PME activity increased during pattern-triggered immunity and after inoculation with either pathogen. The increase of PME activity in response to pathogen treatment was concomitant with a decrease in pectin methylesterification. The pathogen-induced PME activity did not require salicylic acid or ethylene signaling, but was dependent on jasmonic acid signaling. In the case of induction by A. brassicicola, the ethylene response factor, but not the MYC2 branch of jasmonic acid signaling, contributed to induction of PME activity, whereas in the case of induction by Pma ES4326, both branches contributed. There are 66 PME genes in Arabidopsis, suggesting extensive genetic redundancy. Nevertheless, selected pme single, double, triple and quadruple mutants allowed significantly more growth of Pma ES4326 than wild-type plants, indicating a role of PMEs in resistance to this pathogen. No decreases in total PME activity were detected in these pme mutants, suggesting that the determinant of immunity is not total PME activity; rather, it is some specific effect of PMEs such as changes in the pattern of pectin methylesterification.

  9. Identification of pectin methylesterase 3 as a basic pectin methylesterase isoform involved in adventitious rooting in Arabidopsis thaliana.

    Science.gov (United States)

    Guénin, Stéphanie; Mareck, Alain; Rayon, Catherine; Lamour, Romain; Assoumou Ndong, Yves; Domon, Jean-Marc; Sénéchal, Fabien; Fournet, Françoise; Jamet, Elisabeth; Canut, Hervé; Percoco, Giuseppe; Mouille, Grégory; Rolland, Aurélia; Rustérucci, Christine; Guerineau, François; Van Wuytswinkel, Olivier; Gillet, Françoise; Driouich, Azeddine; Lerouge, Patrice; Gutierrez, Laurent; Pelloux, Jérôme

    2011-10-01

    • Here, we focused on the biochemical characterization of the Arabidopsis thaliana pectin methylesterase 3 gene (AtPME3; At3g14310) and its role in plant development. • A combination of biochemical, gene expression, Fourier transform-infrared (FT-IR) microspectroscopy and reverse genetics approaches were used. • We showed that AtPME3 is ubiquitously expressed in A. thaliana, particularly in vascular tissues. In cell wall-enriched fractions, only the mature part of the protein was identified, suggesting that it is processed before targeting the cell wall. In all the organs tested, PME activity was reduced in the atpme3-1 mutant compared with the wild type. This was related to the disappearance of an activity band corresponding to a pI of 9.6 revealed by a zymogram. Analysis of the cell wall composition showed that the degree of methylesterification (DM) of galacturonic acids was affected in the atpme3-1 mutant. A change in the number of adventitious roots was found in the mutant, which correlated with the expression of the gene in adventitious root primordia. • Our results enable the characterization of AtPME3 as a major basic PME isoform in A. thaliana and highlight its role in adventitious rooting.

  10. Involvement of Fungal Pectin Methylesterase Activity in the Interaction Between Fusarium graminearum and Wheat.

    Science.gov (United States)

    Sella, Luca; Castiglioni, Carla; Paccanaro, Maria Chiara; Janni, Michela; Schäfer, Wilhelm; D'Ovidio, Renato; Favaron, Francesco

    2016-04-01

    The genome of Fusarium graminearum, the causal agent of Fusarium head blight of wheat, contains two putative pectin methylesterase (PME)-encoding genes. However, when grown in liquid culture containing pectin, F. graminearum produces only a single PME, which was purified and identified. Its encoding gene, expressed during wheat spike infection, was disrupted by targeted homologous recombination. Two Δpme mutant strains lacked PME activity but were still able to grow on highly methyl-esterified pectin even though their polygalacturonase (PG) activity showed a reduced capacity to depolymerize this substrate. The enzymatic assays performed with purified F. graminearum PG and PME demonstrated an increase in PG activity in the presence of PME on highly methyl-esterified pectin. The virulence of the mutant strains was tested on Triticum aestivum and Triticum durum spikes, and a significant reduction in the percentage of symptomatic spikelets was observed between 7 and 12 days postinfection compared with wild type, demonstrating that the F. graminearum PME contributes to fungal virulence on wheat by promoting spike colonization in the initial and middle stages of infection. In contrast, transgenic wheat plants with increased levels of pectin methyl esterification did not show any increase in resistance to the Δpme mutant, indicating that the infectivity of the fungus relies only to a certain degree on pectin degradation.

  11. Influence of pH on the Structure and Function of Kiwi Pectin Methylesterase Inhibitor.

    Science.gov (United States)

    Bonavita, Alessandro; Carratore, Vitale; Ciardiello, Maria Antonietta; Giovane, Alfonso; Servillo, Luigi; D'Avino, Rossana

    2016-07-27

    Pectin methylesterase is a pectin modifying enzyme that plays a key role in plant physiology. It is also an important quality-related enzyme in plant-based food products. The pectin methylesterase inhibitor (PMEI) from kiwifruit inhibits this enzyme activity and is widely used as an efficient tool for research purposes and also recommended in the context of fruit and vegetable processing. Using several methodologies of protein biochemistry, including circular dichroism and fluorescence spectroscopy, chemical modifications, direct protein-sequencing, enzyme activity, and bioinformatics analysis of the crystal structure, this study demonstrates that conformational changes occur in kiwi PMEI by the pH rising over 6.0 bringing about structure loosening, exposure, and cleavage of a natively buried disulfide bond, unfolding and aggregation, ultimately determining the loss of ability of kiwi PMEI to bind and inhibit PME. pH-induced structural changes are prevented when PMEI is already engaged in complex or is in a solution of high ionic strength.

  12. Strawberry pectin methylesterase (PME): purification, characterization, thermal and high-pressure inactivation.

    Science.gov (United States)

    Ly-Nguyen, Binh; Van Loey, Ann M; Fachin, Diana; Verlent, Isabel; Duvetter, Thomas; Vu, Son T; Smout, Chantal; Hendrickx, Marc E

    2002-01-01

    Pectin methylesterase (PME) was extracted from strawberries (Fragaria ananassa, cv Elsanta) and purified by affinity chromatography on a CNBr-Sepharose 4B-PME-inhibitor column. A single protein and PME activity peak was obtained. A biochemical characterization in terms of molecular mass, pI, and kinetic parameters of strawberry PME was performed. In a second step, the thermal and high-pressure stability of the enzyme was studied. Isothermal and combined isothermal-isobaric inactivation of purified strawberry PME could be described by a fractional-conversion model. Purified strawberry PME is much more stable toward high-pressure treatments in comparison to those from oranges and bananas.

  13. A functional pectin methylesterase inhibitor protein (SolyPMEI) is expressed during tomato fruit ripening and interacts with PME-1.

    Science.gov (United States)

    Reca, Ida Barbara; Lionetti, Vincenzo; Camardella, Laura; D'Avino, Rossana; Giardina, Thierry; Cervone, Felice; Bellincampi, Daniela

    2012-07-01

    A pectin methylesterase inhibitor (SolyPMEI) from tomato has been identified and characterised by a functional genomics approach. SolyPMEI is a cell wall protein sharing high similarity with Actinidia deliciosa PMEI (AdPMEI), the best characterised inhibitor from kiwi. It typically affects the activity of plant pectin methylesterases (PMEs) and is inactive against a microbial PME. SolyPMEI transcripts were mainly expressed in flower, pollen and ripe fruit where the protein accumulated at breaker and turning stages of ripening. The expression of SolyPMEI correlated during ripening with that of PME-1, the major fruit specific PME isoform. The interaction of SolyPMEI with PME-1 was demonstrated in ripe fruit by gel filtration and by immunoaffinity chromatography. The analysis of the zonal distribution of PME activity and the co-localization of SolyPMEI with high esterified pectins suggest that SolyPMEI regulates the spatial patterning of distribution of esterified pectins in fruit.

  14. Purification and characterization of a papaya (Carica papaya L.) pectin methylesterase isolated from a commercial papain preparation

    Science.gov (United States)

    We purified a single stable pectin methylesterase (CpL-PME; EC 3.1.1.11) from a commercial papain preparation, which is isolated from Carica papaya (L.) fruit latex. This CpL-PME was separated from the abundant cysteine endopeptidases activities using sequential hydrophobic interaction and cation-ex...

  15. The Pectin Methylesterase Gene Complement of Phytophthora sojae: Structural and Functional Analyses, and the Evolutionary Relationships with Its Oomycete Homologs.

    Science.gov (United States)

    Horowitz, Brent B; Ospina-Giraldo, Manuel D

    2015-01-01

    Phytophthora sojae is an oomycete pathogen that causes the disease known as root and stem rot in soybean plants, frequently leading to massive economic damage. Additionally, P. sojae is increasingly being utilized as a model for phytopathogenic oomycete research. Despite the economic and scientific importance of P. sojae, the mechanism by which it penetrates the host roots is not yet fully understood. It has been found that oomycetes are not capable of penetrating the cell wall solely through mechanical force, suggesting that alternative factors facilitate breakdown of the host cell wall. Pectin methylesterases have been suggested to be important for Phytophthora pathogenicity, but no data exist on their role in the P. sojae infection process. We have scanned the newly revised version of the annotated P. sojae genome for the presence of putative pectin methylesterases 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. sojae models, and investigated the gene expression levels throughout the early course of infection on soybean plants. We found that P. sojae contains a large repertoire of pectin methylesterase-coding genes and that most of these genes display similar motifs in the promoter region, indicating the possibility of a shared regulatory mechanism. Phylogenetic analyses confirmed the evolutionary relatedness of the pectin methylesterase-coding genes within and across Phytophthora spp. In addition, the gene duplication events that led to the emergence of this gene family appear to have occurred prior to many speciation events in the genus Phytophthora. Our results also indicate that the highest levels of expression occurred in the first 24 hours post inoculation, with expression falling after this time. Our study provides evidence that pectin methylesterases may be important for the early action of the P. sojae infection process.

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

    Science.gov (United States)

    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.

  17. Effects of controlled-frequency moderate electric fields on pectin methylesterase and polygalacturonase activities in tomato homogenate.

    Science.gov (United States)

    Samaranayake, Chaminda P; Sastry, Sudhir K

    2016-05-15

    The effect of controlled-frequency moderate electric field treatments on pectin methylesterase and polygalcturonase activities in tomato homogenate was investigated by subjecting identically treated control and electrically-treated samples to the same temperature history. Additionally, a model was developed for the motion of the enzyme molecules subjected to an electric field. Results show that the application of electric fields at a low field strength (0.4V/cm) constant temperature (65°C) has a statistically significant effect on pectin methylesterase activity, typically at or lower than 60 Hz. At higher frequencies, the effects are negligible. Molecular motion simulations suggest that the efficacy at low frequencies may be due to the amplitude of motion being of the order of the intermolecular distance for water. Higher frequencies result in small overall displacements due to rapid reversals in the direction of motion.

  18. Structure and functional features of olive pollen pectin methylesterase using homology modeling and molecular docking methods.

    Science.gov (United States)

    Jimenez-Lopez, Jose C; Kotchoni, Simeon O; Rodríguez-García, María I; Alché, Juan D

    2012-12-01

    Pectin methylesterases (PMEs), a multigene family of proteins with multiple differentially regulated isoforms, are key enzymes implicated in the carbohydrates (pectin) metabolism of cell walls. Olive pollen PME has been identified as a new allergen (Ole e 11) of potential relevance in allergy amelioration, since it exhibits high prevalence among atopic patients. In this work, the structural and functional characterization of two olive pollen PME isoforms and their comparison with other PME plants was performed by using different approaches: (1) the physicochemical properties and functional-regulatory motifs characterization, (2) primary sequence analysis, 2D and 3D comparative structural features study, (3) conservation and evolutionary analysis, (4) catalytic activity and regulation based on molecular docking analysis of a homologue PME inhibitor, and (5) B-cell epitopes prediction by sequence and structural based methods and protein-protein interaction tools, while T-cell epitopes by inhibitory concentration and binding score methods. Our results indicate that the structural differences and low conservation of residues, together with differences in physicochemical and posttranslational motifs might be a mechanism for PME isovariants generation, regulation, and differential surface epitopes generation. Olive PMEs perform a processive catalytic mechanism, and a differential molecular interaction with specific PME inhibitor, opening new possibilities for PME activity regulation. Despite the common function of PMEs, differential features found in this study will lead to a better understanding of the structural and functional characterization of plant PMEs and help to improve the component-resolving diagnosis and immunotherapy of olive pollen allergy by epitopes identification.

  19. Relationship between Mutations of the Pectin Methylesterase Gene in Soybean and the Hardness of Cooked Beans.

    Science.gov (United States)

    Toda, Kyoko; Hirata, Kaori; Masuda, Ryoichi; Yasui, Takeshi; Yamada, Tetsuya; Takahashi, Koji; Nagaya, Taiko; Hajika, Makita

    2015-10-14

    Hardness of cooked soybeans [Glycine max (L). Merr.] is an important attribute in food processing. We found one candidate gene, Glyma03g03360, to be associated with the hardness of cotyledons of cooked soybeans, based on a quantitative trait locus and fine-scale mapping analyses using a recombinant inbred line population developed from a cross between two Japanese cultivars, "Natto-shoryu" and "Hyoukei-kuro 3". Analysis of the DNA sequence of Glyma03g03360, a pectin methylesterase gene homologue, revealed three patterns of mutations, two of which result in truncated proteins and one of which results in an amino acid substitution. The truncated proteins are presumed to lack the enzymatic activity of Glyma03g03360. We classified 24 cultivars into four groups based on the sequence of Glyma03g03360. The texture analysis using the 22 cultivars grown in different locations indicated that protein truncation of Glyma03g03360 resulted in softer cotyledons of cooked soybeans, which was further confirmed by texture analysis performed using F2 populations of a cross between "Enrei" and "LD00-3309", and between "Satonohohoemi" and "Sakukei 98". A positive correlation between hardness and calcium content implies the possible effect of calcium binding to pectins on the hardness of cooked soybean cotyledons.

  20. Extraction and characterization of pectin methylesterase from Alyanak apricot (Prunus armeniaca L).

    Science.gov (United States)

    Ünal, M Ümit; Şener, Aysun

    2015-02-01

    This study was carried out to determine some of the biochemical properties of pectin methylesterase (PME) from Alyanak apricot which is an important variety grown in Malatya region of Turkey. The enzyme had high activity in a pH range of 7.0-8.0 with the maximal activity occurring at pH 7.5. However, the enzyme activity at high and low pH values was very low. The optimum temperature for maximal PME activity was found to be 60 °C. The activity of PME has been enhanced by NaCl, particularly at 0.15 M. Km and Vmax values for Alyanak apricot PME using apple pectin as substrate were found to be 1.69 mg/mL (r(2) = 0.992) and 3.41 units/mL, respectively. The enzyme was stable at 30-45 °C/10 min whereas it lost nearly all of its activity at 80 °C/10 min. Ea and Z values were found to be 206.1 kJ/mol (r(2) = 0.993) and 10.62 °C (r(2) = 0.992), respectively.

  1. Genome-wide identification and expression analysis of rice pectin methylesterases: Implication of functional roles of pectin modification in rice physiology.

    Science.gov (United States)

    Jeong, Ho Young; Nguyen, Hong Phuong; Lee, Chanhui

    2015-07-01

    Pectin, which is enriched in primary cell walls and middle lamellae, is an essential polysaccharide in all higher plants. Homogalacturonans (HGA), a major form of pectin, are synthesized and methylesterified by enzymes localized in the Golgi apparatus and transported into the cell wall. Depending on cell type, the degree and pattern of pectin methylesterification are strictly regulated by cell wall-localized pectin methylesterases (PMEs). Despite its importance in plant development and growth, little is known about the physiological functions of pectin in rice, which contains 43 different types of PME. The presence of pectin in rice cell walls has been substantiated by uronic acid quantification and immunodetection of JIM7 monoclonal antibodies. We performed PME activity assays with cell wall proteins isolated from different rice tissues. In accordance with data from Arabidopsis, the highest activity was observed in germinating tissues, young culm, and spikelets, where cells are actively elongating. Transcriptional profiling of OsPMEs by real-time PCR and meta-analysis indicates that PMEs exhibit spatial- and stress-specific expression patterns during rice development. Based on in silico analysis, we identified subcellular compartments, isoelectric point, and cleavage sites of OsPMEs. Our findings provide an important tool for further studies seeking to unravel the functional importance of pectin modification during plant growth and abiotic and biotic responses of grass plants.

  2. Association of specific pectin methylesterases with Al-induced root elongation inhibition in rice.

    Science.gov (United States)

    Yang, Xiao Ying; Zeng, Zhang Hui; Yan, Jing Ying; Fan, Wei; Bian, Hong Wu; Zhu, Mu Yuan; Yang, Jian Li; Zheng, Shao Jian

    2013-08-01

    The negative charges of cell wall pectin molecules attributed by pectin methylesterase (PME, EC 3.1.1.11) contribute to Al binding capacity. We examined the expression profiles of 35 members of the PME gene family in the root apex of an Al-sensitive rice 'Zhefu802' under Al stress. While root elongation was inhibited by 40% after 3-h exposure to 25 µM Al, cell wall PME activity and the abundance of eight PME genes transcripts were increased. The same Al treatment which had almost no effect on root elongation of an Al-resistant rice ssp. japonica 'Nipponbare' did not change the expression patterns of these eight PME genes. However, when Al concentration was increased to 50 µM, by which the root elongation of 'Nipponbare' was inhibited by 40% too, the expression of these PME genes were also upregulated except two genes with no signal. These suggest a possible correlation between the upregulated genes and Al-induced inhibition of root elongation in rice. Furthermore, these eight PME genes behaved differently when subjected to CdCl2 and LaCl3 treatments, implying the specificity of different PME genes in response to different metal toxicities. The transgenic rice overexpressing one of these eight PME genes OsPME14 showed higher PME activity and Al content in root tip cell wall, and became more sensitive to Al stress, verifying the involvement of the specific PME gene in Al toxicity. Therefore, our results provided the molecular evidence to connect the expression of specific PME genes with the Al-induced inhibition of root elongation in rice.

  3. Advances in understanding pectin methylesterase inhibitor in kiwi fruit: an immunological approach.

    Science.gov (United States)

    Vandevenne, Evelien; Christiaens, Stefanie; Van Buggenhout, Sandy; Jolie, Ruben P; González-Vallinas, Margarita; Duvetter, Thomas; Declerck, Paul J; Hendrickx, Marc E; Gils, Ann; Van Loey, Ann

    2011-02-01

    In order to gain insight into the in situ properties and localisation of kiwi pectin methylesterase inhibitor (PMEI), a toolbox of monoclonal antibodies (MA) towards PMEI was developed. Out of a panel of MA generated towards kiwi PMEI, three MA, i.e. MA-KI9A8, MA-KI15C12 and MA-KI15G7, were selected. Thorough characterisation proved that these MA bind specifically to kiwi PMEI and kiwi PMEI in complex with plant PME and recognise a linear epitope on PMEI. Extract screening of green kiwi (Actinidia deliciosa) and gold kiwi (Actinidia chinensis) confirmed the potential use of these MA as probes to screen for PMEI in other sources. Tissue printing revealed the overall presence of PMEI in pericarp and columella of ripe kiwi fruit. Further analysis on the cellular level showed PMEI label concentrated in the middle lamella and in the cell-wall region near the plasmalemma. Intercellular spaces, however, were either completely filled or lined with label. In conclusion, the developed toolbox of antibodies towards PMEI can be used as probes to localise PMEI on different levels, which can be of relevance for plant physiologists as well as food technologists.

  4. Inactivation of pectin methylesterase by immobilized trypsins from cunner fish and bovine pancreas.

    Science.gov (United States)

    Li, Dan; Matos, Madyu; Simpson, Benjamin K

    2013-01-01

    Immobilized cunner fish trypsin was used to inactivate pectin methylesterase (PME). The effects of different reaction conditions (e.g., incubation time, PME concentration, and temperature) on PME inactivation and kinetics of inactivation were investigated. Temperature, incubation time, and PME concentration significantly affected the extent of PME inactivation. Generally, higher temperature, longer incubation time, and low PME concentration caused more PME inactivation. The immobilized fish trypsin had higher capacity to inactivate PME than immobilized bovine trypsin. The inactivation efficiency of the immobilized fish trypsin was about 20% higher than that of its bovine counterpart. However, PME inactivated by both trypsins regained partial activity during storage at 4°C, with immobilized fish trypsin-treated PME regaining more of its original activity than the immobilized bovine trypsin-treated PME. Heat-denatured PME was hydrolyzed more extensively by immobilized fish trypsin than by its bovine counterpart. The rate constants increased, whereas the D-values decreased with temperature for both immobilized fish and bovine trypsins. The inactivation rate constants of immobilized fish trypsin at all the temperatures investigated (i.e., 15-35°C) were higher than those of immobilized bovine trypsin. Furthermore, the activation energy (Ea ) of PME inactivation by immobilized fish trypsin was lower than that of immobilized bovine trypsin.

  5. Wound-induced pectin methylesterases enhance banana (Musa spp. AAA) susceptibility to Fusarium oxysporum f. sp. cubense.

    Science.gov (United States)

    Ma, Li; Jiang, Shuang; Lin, Guimei; Cai, Jianghua; Ye, Xiaoxi; Chen, Houbin; Li, Minhui; Li, Huaping; Takác, Tomás; Samaj, Jozef; Xu, Chunxiang

    2013-05-01

    Recent studies suggest that plant pectin methylesterases (PMEs) are directly involved in plant defence besides their roles in plant development. However, the molecular mechanisms of PME action on pectins are not well understood. In order to understand how PMEs modify pectins during banana (Musa spp.)-Fusarium interaction, the expression and enzyme activities of PMEs in two banana cultivars, highly resistant or susceptible to Fusarium, were compared with each other. Furthermore, the spatial distribution of PMEs and their effect on pectin methylesterification of 10 individual homogalacturonan (HG) epitopes with different degrees of methylesterification (DMs) were also examined. The results showed that, before pathogen treatment, the resistant cultivar displayed higher PME activity than the susceptible cultivar, corresponding well to the lower level of pectin DM. A significant increase in PME expression and activity and a decrease in pectin DM were observed in the susceptible cultivar but not in the resistant cultivar when plants were wounded, which was necessary for successful infection. With the increase of PME in the wounded susceptible cultivar, the JIM5 antigen (low methyestrified HGs) increased. Forty-eight hours after pathogen infection, the PME activity and expression in the susceptible cultivar were higher than those in the resistant cultivar, while the DM was lower. In conclusion, the resistant and the susceptible cultivars differ significantly in their response to wounding. Increased PMEs and thereafter decreased DMs acompanied by increased low methylesterified HGs in the root vascular cylinder appear to play a key role in determination of banana susceptibility to Fusarium.

  6. Analysis of LuPME3, a pectin methylesterase from Linum usitatissimum, revealed a variability in PME proteolytic maturation.

    Science.gov (United States)

    Mareck, Alain; Lamour, Romain; Schaumann, Annick; Chan, Philippe; Driouich, Azeddine; Pelloux, Jérôme; Lerouge, Patrice

    2012-01-01

    Pectin methylesterase (PME) catalyses the de-methylesterification of pectin in plant cell walls during cell elongation. (1) Pectins are mainly composed of α(1, 4)-D-galacturonosyl acid units that are synthesised in a methylesterified form in the Golgi apparatus to prevent any interaction with Ca2+ ions during their intracellular transport. (2) The highly methylesterified pectins are then secreted into the apoplasm (3) and subsequently de-methylesterified in muro by PMEs. This can either induce the formation of pectin gels through the Ca2+ crosslinking of neighbouring non-methylesterified chains or create substrates for pectin-degrading enzymes such as polygalacturonases and pectate lyases for the initiation of cell wall loosening. (4) PMEs belong to a large multigene family. Sixty-six PME-related genes are predicted in the Arabidopsis genome. (1) Among them, we have recently shown that AtPME3 (At3g14310), a major basic PME isoform in A. thaliana, is ubiquitously expressed in vascular tissues and play a role in adventitious rooting. (5) In flax (Linum usitatissimum), three genes encoding PMEs have been sequenced so far, including LuPME3, the orthologue of AtPME3. Analysis of the LuPME3 isoform brings new insights into the processing of these proteins.

  7. Promotion of testa rupture during garden cress germination involves seed compartment-specific expression and activity of pectin methylesterases.

    Science.gov (United States)

    Scheler, Claudia; Weitbrecht, Karin; Pearce, Simon P; Hampstead, Anthony; Büttner-Mainik, Annette; Lee, Kieran J D; Voegele, Antje; Oracz, Krystyna; Dekkers, Bas J W; Wang, Xiaofeng; Wood, Andrew T A; Bentsink, Leónie; King, John R; Knox, J Paul; Holdsworth, Michael J; Müller, Kerstin; Leubner-Metzger, Gerhard

    2015-01-01

    Pectin methylesterase (PME) controls the methylesterification status of pectins and thereby determines the biophysical properties of plant cell walls, which are important for tissue growth and weakening processes. We demonstrate here that tissue-specific and spatiotemporal alterations in cell wall pectin methylesterification occur during the germination of garden cress (Lepidium sativum). These cell wall changes are associated with characteristic expression patterns of PME genes and resultant enzyme activities in the key seed compartments CAP (micropylar endosperm) and RAD (radicle plus lower hypocotyl). Transcriptome and quantitative real-time reverse transcription-polymerase chain reaction analysis as well as PME enzyme activity measurements of separated seed compartments, including CAP and RAD, revealed distinct phases during germination. These were associated with hormonal and compartment-specific regulation of PME group 1, PME group 2, and PME inhibitor transcript expression and total PME activity. The regulatory patterns indicated a role for PME activity in testa rupture (TR). Consistent with a role for cell wall pectin methylesterification in TR, treatment of seeds with PME resulted in enhanced testa permeability and promoted TR. Mathematical modeling of transcript expression changes in germinating garden cress and Arabidopsis (Arabidopsis thaliana) seeds suggested that group 2 PMEs make a major contribution to the overall PME activity rather than acting as PME inhibitors. It is concluded that regulated changes in the degree of pectin methylesterification through CAP- and RAD-specific PME and PME inhibitor expression play a crucial role during Brassicaceae seed germination.

  8. Nanostructural modification of a model homogalacturonan with a novel pectin methylesterase: Effects of pH on nanostructure, enzyme mode of action and substrate functionality

    Science.gov (United States)

    A pectin methylesterase (CpL-PME) present in a commercial papain preparation was used to modify the amount and distribution of charge in a model pectic homogalacturonan (HG) at pH 4.5 and pH 7.5. Introduced negatively charged demethylesterified blocks (DMB) were excised as oligomers with a limited e...

  9. Determination of pectin methylesterase activity in commercial pectinases and study of the inactivation kinetics through two potentiometric procedures

    Directory of Open Access Journals (Sweden)

    Samantha Lemke Gonzalez

    2011-06-01

    Full Text Available Pectinases are enzymes that degrade pectic substances and are widely used in juice and fruit beverages to improve the quality of the process. The objective of this study was to determine the optimum pH and temperature of two samples of commercial pectinases and propose an alternative procedure to determine the residual activity comparing the data with those of the traditional procedure. The pectin methylesterase (PME activity in Pectinex 100 L Plus and Panzyn Clears was determined by potentiometry. The reaction consisted of 5.00 mg.mL-1 apple pectin, 0.100 mol.L-1 NaCl, and 50 µL enzyme to a total volume of 30 mL. The pectin reaction in the presence of PME in all experiments revealed a first order kinetics. The PME in the two enzyme preparations showed higher activity at pH 4.0 to 4.5 and temperature of 45 ºC. From the results of both procedures ΔV NaOH/Δt and ΔpH/Δt, it was concluded that the inactivation of PME occurred at 75 ºC. The results obtained from the ratio ΔpH/Δt showed good correlation with those obtained from the ratio ΔV NaOH/Δt. In the reaction accompanied by the ratio ΔpH/Δt, the release of H3O+ occurred in the real time reaction.

  10. Purification and characterization of a papaya (Carica papaya L.) pectin methylesterase isolated from a commercial papain preparation.

    Science.gov (United States)

    Vasu, Prasanna; Savary, Brett J; Cameron, Randall G

    2012-07-15

    We purified a Carica papaya pectin methylesterase (CpL-PME; EC 3.1.1.11) from a commercial papain preparation. This CpL-PME was separated from the abundant cysteine endopeptidases activities using sequential hydrophobic interaction and cation-exchange chromatographies and then purified by affinity chromatography using Sepharose-immobilized kiwi PME inhibitor protein to obtain a single electrophoretically homogeneous protein. The enzyme was purified 92-fold with 38% yield, providing a specific activity of 1200 U/mg. The molecular weight was determined to be 35,135 by MALDI-TOF-MS in linear mode. MALDI-TOF-MS peptide mass fingerprinting following trypsin digestion indicated CpL-PME represents a novel Carica PME isoform. The CpL-PME required salt for activity, and it showed a broad activity range (pH 6-9) and moderate thermostability (optimum ca. 70°C). A calcium-insensitive methylated lime pectin treated with CpL-PME to reduce degree of methylesterification by 6% converted the substrate to high calcium sensitivity, indicating a processive mode of action. These properties support further research to apply CpL-PME to tailor pectin nanostructure.

  11. The Grapevine VvPMEI1 Gene Encodes a Novel Functional Pectin Methylesterase Inhibitor Associated to Grape Berry Development.

    Science.gov (United States)

    Lionetti, Vincenzo; Raiola, Alessandro; Mattei, Benedetta; Bellincampi, Daniela

    2015-01-01

    Pectin is secreted in a highly methylesterified form and partially de-methylesterified in the cell wall by pectin methylesterases (PMEs). PME activity is expressed during plant growth, development and stress responses. PME activity is controlled at the post-transcriptional level by proteins named PME inhibitors (PMEIs). We have identified, expressed and characterized VvPMEI1, a functional PME inhibitor of Vitis vinifera. VvPMEI1 typically affects the activity of plant PMEs and is inactive against microbial PMEs. The kinetics of PMEI-PME interaction, studied by surface plasmon resonance, indicates that the inhibitor strongly interacts with PME at apoplastic pH while the stability of the complex is reduced by increasing the pH. The analysis of VvPMEI1 expression in different grapevine tissues and during grape fruit development suggests that this inhibitor controls PME activity mainly during the earlier phase of berry development. A proteomic analysis performed at this stage indicates a PME isoform as possible target of VvPMEI1.

  12. Short term changes in methanol emission and pectin methylesterase activity are not directly affected by light in Lycopersicon esculentum

    Science.gov (United States)

    Oikawa, P. Y.; Li, L.; Timko, M. P.; Mak, J. E.; Lerdau, M. T.

    2011-04-01

    Plants are an important source of atmospheric methanol (MeOH), the second most abundant organic gas after methane. Factors regulating phytogenic MeOH production are not well constrained in current MeOH emission models. Previous studies have indicated that light may have a direct influence on MeOH production. As light is known to regulate cell wall expansion, it was predicted that light would stimulate MeOH production through the pectin methylesterase (PME) pathway. MeOH emissions normalized for stomatal conductance (gs) did not, however, increase with light over short time scales (20-30 min). After experimentally controlling for gs and temperature, no light activation of PME activity or MeOH emission was observed. The results clearly demonstrate that light does not directly influence short-term changes in MeOH production and emission. Our data suggest that substrate limitation may be important in regulating MeOH production over short time scales. Future investigation of the long-term impacts of light on MeOH production may increase understanding of MeOH emission dynamics at the seasonal time scale.

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

    Science.gov (United States)

    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.

  14. Cellulose binding protein from the parasitic nematode Heterodera schachtii interacts with Arabidopsis pectin methylesterase: cooperative cell wall modification during parasitism.

    Science.gov (United States)

    Hewezi, Tarek; Howe, Peter; Maier, Tom R; Hussey, Richard S; Mitchum, Melissa Goellner; Davis, Eric L; Baum, Thomas J

    2008-11-01

    Plant-parasitic cyst nematodes secrete a complex of cell wall-digesting enzymes, which aid in root penetration and migration. The soybean cyst nematode Heterodera glycines also produces a cellulose binding protein (Hg CBP) secretory protein. To determine the function of CBP, an orthologous cDNA clone (Hs CBP) was isolated from the sugar beet cyst nematode Heterodera schachtii, which is able to infect Arabidopsis thaliana. CBP is expressed only in the early phases of feeding cell formation and not during the migratory phase. Transgenic Arabidopsis expressing Hs CBP developed longer roots and exhibited enhanced susceptibility to H. schachtii. A yeast two-hybrid screen identified Arabidopsis pectin methylesterase protein 3 (PME3) as strongly and specifically interacting with Hs CBP. Transgenic plants overexpressing PME3 also produced longer roots and exhibited increased susceptibility to H. schachtii, while a pme3 knockout mutant showed opposite phenotypes. Moreover, CBP overexpression increases PME3 activity in planta. Localization studies support the mode of action of PME3 as a cell wall-modifying enzyme. Expression of CBP in the pme3 knockout mutant revealed that PME3 is required but not the sole mechanism for CBP overexpression phenotype. These data indicate that CBP directly interacts with PME3 thereby activating and potentially targeting this enzyme to aid cyst nematode parasitism.

  15. Short term changes in methanol emission and pectin methylesterase activity are not directly affected by light in Lycopersicon esculentum

    Directory of Open Access Journals (Sweden)

    M. T. Lerdau

    2011-04-01

    Full Text Available Plants are an important source of atmospheric methanol (MeOH, the second most abundant organic gas after methane. Factors regulating phytogenic MeOH production are not well constrained in current MeOH emission models. Previous studies have indicated that light may have a direct influence on MeOH production. As light is known to regulate cell wall expansion, it was predicted that light would stimulate MeOH production through the pectin methylesterase (PME pathway. MeOH emissions normalized for stomatal conductance (gs did not, however, increase with light over short time scales (20–30 min. After experimentally controlling for gs and temperature, no light activation of PME activity or MeOH emission was observed. The results clearly demonstrate that light does not directly influence short-term changes in MeOH production and emission. Our data suggest that substrate limitation may be important in regulating MeOH production over short time scales. Future investigation of the long-term impacts of light on MeOH production may increase understanding of MeOH emission dynamics at the seasonal time scale.

  16. Short term changes in methanol emission and pectin methylesterase activity are not directly affected by light in Lycopersicon esculentum

    Directory of Open Access Journals (Sweden)

    M. T. Lerdau

    2011-01-01

    Full Text Available Plants are an important source of atmospheric methanol (MeOH, the second most abundant organic gas after methane. Factors regulating phytogenic MeOH production are not well constrained in current MeOH emission models. Previous studies have indicated that light may have a direct influence on MeOH production. As light is known to regulate cell wall expansion, it was predicted that light would stimulate MeOH production through the pectin methylesterase (PME pathway. MeOH emissions normalized for stomatal conductance (gs did not, however, increase with light over short time scales (20–30 min. After experimentally controlling for gs and temperature, no light activation of PME activity or MeOH emission was observed. The results clearly demonstrate that light does not directly influence short-term changes in MeOH production and emission. Our data suggest that substrate limitation may be important in regulating MeOH production over short time scales. Future investigation of the long-term impacts of light on MeOH production may increase understanding of MeOH emission dynamics at the seasonal time scale.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. Defense Responses in Aspen with Altered Pectin Methylesterase Activity Reveal the Hormonal Inducers of Tyloses1[OPEN

    Science.gov (United States)

    Leśniewska, Joanna; Krzesłowska, Magdalena; Kushwah, Sunita; Sundberg, Björn; Moritz, Thomas

    2017-01-01

    Tyloses are ingrowths of parenchyma cells into the lumen of embolized xylem vessels, thereby protecting the remaining xylem from pathogens. They are found in heartwood, sapwood, and in abscission zones and can be induced by various stresses, but their molecular triggers are unknown. Here, we report that down-regulation of PECTIN METHYLESTERASE1 (PtxtPME1) in aspen (Populus tremula × tremuloides) triggers the formation of tyloses and activation of oxidative stress. We tested whether any of the oxidative stress-related hormones could induce tyloses in intact plantlets grown in sterile culture. Jasmonates, including jasmonic acid (JA) and methyl jasmonate, induced the formation of tyloses, whereas treatments with salicylic acid (SA) and 1-aminocyclopropane-1-carboxylic acid (ACC) were ineffective. SA abolished the induction of tyloses by JA, whereas ACC was synergistic with JA. The ability of ACC to stimulate tyloses formation when combined with JA depended on ethylene (ET) signaling, as shown by a decrease in the response in ET-insensitive plants. Measurements of internal ACC and JA concentrations in wild-type and ET-insensitive plants treated simultaneously with these two compounds indicated that ACC and JA regulate each other’s concentration in an ET-dependent manner. The findings indicate that jasmonates acting synergistically with ethylene are the key molecular triggers of tyloses. PMID:27923986

  19. A novel low-temperature-active pectin methylesterase from Penicillium chrysogenum F46 with high efficiency in fruit firming.

    Science.gov (United States)

    Pan, Xia; Tu, Tao; Wang, Liwen; Luo, Huiying; Ma, Rui; Shi, Pengjun; Meng, Kun; Yao, Bin

    2014-11-01

    A pectin methylesterase gene (pe8F46) was cloned from Penicillium chrysogenum F46 and successfully expressed in Pichia pastoris. The full-length cDNA consists of 969 bp and encodes a 322-residue polypeptide with the calculated molecular weight of 34.1 kDa. Deduced PE8F46 belongs to family 8 of carbohydrate esterases and shares 54% identity with a functionally characterised counterpart from Myceliophthora thermophile. Purified recombinant PE8F46 showed the optimal activity at pH 5.0 and 40°C, and remained 52% maximum activity even at 10°C. An orthogonal experiment was employed to determine the best conditions for firming pineapple dices. After incubation with 0.75% (w/v) PE8F46 and 0.4% calcium lactate (w/v) for 20 min, the firmness of pineapple dices was improved by 47.6%, 13.7% higher than that of a commercial pectinase complex. These results suggest that PE8F46 has application potential in the food industry.

  20. AtPME3, a ubiquitous cell wall pectin methylesterase of Arabidopsis thaliana, alters the metabolism of cruciferin seed storage proteins during post-germinative growth of seedlings.

    Science.gov (United States)

    Guénin, Stéphanie; Hardouin, Julie; Paynel, Florence; Müller, Kerstin; Mongelard, Gaëlle; Driouich, Azeddine; Lerouge, Patrice; Kermode, Allison R; Lehner, Arnaud; Mollet, Jean-Claude; Pelloux, Jérôme; Gutierrez, Laurent; Mareck, Alain

    2017-02-01

    AtPME3 (At3g14310) is a ubiquitous cell wall pectin methylesterase. Atpme3-1 loss-of-function mutants exhibited distinct phenotypes from the wild type (WT), and were characterized by earlier germination and reduction of root hair production. These phenotypical traits were correlated with the accumulation of a 21.5-kDa protein in the different organs of 4-day-old Atpme3-1 seedlings grown in the dark, as well as in 6-week-old mutant plants. Microarray analysis showed significant down-regulation of the genes encoding several pectin-degrading enzymes and enzymes involved in lipid and protein metabolism in the hypocotyl of 4-day-old dark grown mutant seedlings. Accordingly, there was a decrease in proteolytic activity of the mutant as compared with the WT. Among the genes specifying seed storage proteins, two encoding CRUCIFERINS were up-regulated. Additional analysis by RT-qPCR showed an overexpression of four CRUCIFERIN genes in the mutant Atpme3-1, in which precursors of the α- and β-subunits of CRUCIFERIN accumulated. Together, these results provide evidence for a link between AtPME3, present in the cell wall, and CRUCIFERIN metabolism that occurs in vacuoles.

  1. The peculiar structural features of kiwi fruit pectin methylesterase: amino acid sequence, oligosaccharides structure, and modeling of the interaction with its natural proteinaceous inhibitor.

    Science.gov (United States)

    Ciardiello, M Antonietta; D'Avino, Rossana; Amoresano, Angela; Tuppo, Lisa; Carpentieri, Andrea; Carratore, Vito; Tamburrini, Maurizio; Giovane, Alfonso; Pucci, Piero; Camardella, Laura

    2008-04-01

    Pectin methylesterase (PME) from kiwi fruit (Actinidia deliciosa) is a glycoprotein, showing an apparent molecular mass of 50 kDa upon size exclusion chromatography and SDS-PAGE. The primary structure, elucidated by direct sequencing of the protein, comprises 321 amino acid residues providing a molecular mass of 35 kDa. The protein has an acetylated Thr residue at the amino terminus and five N-glycosylation consensus sequences, four of which are actually glycosylated. A careful investigation of the oligosaccharide structures demonstrated that PME glycans belong to complex type oligosaccharides essentially consisting of xylosylated polyfucosylated biantennary structures. Alignment with known mature plant PME sequences indicates that the postulated active site residues are conserved. Kiwi PME activity is inhibited following the interaction with the proteinaceous inhibitor PMEI, isolated from the same source. Gel-filtration experiments show that kiwi PME/PMEI complex is stable in a large pH range and dissociates only at pH 10.0. Modeling of the interaction with the inhibitor was performed by using the crystal structure of the complex between kiwi PMEI and tomato PME as a template. The model shows that the binding site is the same reported for tomato PME. However, additional salt link interactions are found to connect the external loops of kiwi PME to PMEI. This finding may explain the higher pH stability of the complex formed by the two kiwi proteins respect to that formed by PMEI and tomato PME.

  2. Characterization of BcMF23a and BcMF23b, two putative pectin methylesterase genes related to pollen development in Brassica campestris ssp. chinensis.

    Science.gov (United States)

    Lin, Sue; Huang, Li; Yu, Xiaolin; Xiong, Xingpeng; Yue, Xiaoyan; Liu, Tingting; Liang, Ying; Lv, Meiling; Cao, Jiashu

    2017-02-01

    Two homologous genes, Brassica campestris Male Fertility 23a (BcMF23a) and Brassica campestris Male Fertility 23b (BcMF23b), encoding putative pectin methylesterases (PMEs) were isolated from Brassica campestris ssp. chinensis (syn. Brassica rapa ssp. chinensis). These two genes sharing high sequence identity with each other were highly expressed in the fertile flower buds but silenced in the sterile ones of genic male sterile line system ('Bcajh97-01A/B'). Results of RT-PCR and in situ hybridization suggested that BcMF23a and BcMF23b were pollen-expressed genes, whose transcripts were first detected at the binucleate pollen and maintained throughout to the mature pollen grains. Western blot indicated that both of the putative BcMF23a and BcMF23b proteins are approximately 40 kDa, which exhibited extracellular localization revealed by transient expression analysis in the onion epidermal cells. The promoter of BcMF23a was active specifically in pollen during the late pollen developmental stages, while, in addition to the pollen, BcMF23b promoter drove an extra gene expression in the valve margins, abscission layer at the base of the first true leaves, taproot and lateral roots in seedlings.

  3. POLYGALACTURONASE AND PECTIN METHYLESTERASE ACTIVITIES OF CaCl2 TREATED RED-FLESHED DRAGON FRUIT (HYLOCEREUS POLYRHIZUS HARVESTED AT DIFFERENT MATURITY

    Directory of Open Access Journals (Sweden)

    Y. B. Awang

    2013-01-01

    Full Text Available Fruits harvested at different maturity possess different biochemical constituents and physiological properties that make the fruits may react somewhat differently to the postharvest treatment. A study to examine the activity of Polygalacturonase (PG and Pectin Methylesterase (PME enzymes during storage in dragon fruit (Hylocereus polyrhizus harvested at 28 days (Index 3 and 34 days (Index 5 after anthesis and postharvest treated with 0, 2.5, 5.0 and 7.5 g L-1 CaCl2 was performed. The PG activity was lower in younger fruit and vice-versa for PME activity. Increasing concentration of CaCl2 effectively reduced the activity of both enzymes. PG activity for fruit treated with 0, 5 and 7.5 g L-1 CaCl2 increased linearly with the time of storage while its activity for the fruit treated with 2.5 g L-1 CaCl2 was lower at the beginning of storage. PG activity of Index 5 fruits increased almost linearly during storage while its activity in Index 3 fruits was low at the early days of storage and later continued to increase until day seven. At both maturity indices, the PME activity was low at the early days of storage and later continued to increase until day seven. Overall, results obtained indicated that CaCl2 postharvest treatment reduced both PME and PG activities thus slowing down the softening process giving an evident that calcium possess a distinguishable role in the reducing softening of fruit, regardless of maturity index.

  4. Cloning and Functional Analysis of Tobacco Pectin Methylesterase%烟草果胶甲基酯酶(PME)基因的克隆及功能分析

    Institute of Scientific and Technical Information of China (English)

    李春波; 高锋; 钟永旺; 魏春红; 李毅

    2004-01-01

    为了研究果胶甲基酯酶(pectin methyl-esterase,PME)(EC 3.1.1.11)与植物病毒运动蛋白之间的相互作用,应用RT-PCR方法从烟草(Nicotiana benthamiana)中克隆了PME基因,并测定了全序列(GenBank登录号AY238968).序列分析显示该基因由两个保守的结构域组成(PMEI和pectinesterase).DNA印迹结果表明,该基因在基因组中存在多个拷贝,蛋白质印迹表明,植物总蛋白中存在两种形式的PME蛋白,但RNA印迹结果显示,在烟草细胞中只检测到全长的PME转录产物.酵母双杂交结果表明,PME与水稻矮缩病毒Pns11(具有非特异的核酸结合活性)之间存在相互作用,而没有检测到PME与已知的运动蛋白Pns6之间的相互作用,推测Pns11蛋白可能参与了水稻矮缩病毒粒子的运动.%In order to study the interactions between plant virus movement protein and pectin methylesterase ( PME), PME gene from tobacco genome was cloned using RT-PCR method and the sequence was determined ( GenBank accession No. AY238968). Sequence analysis showed that there were two conserved domains in PME protein: PMEI and pectinesterase. Multiple copies of PME gene were detected in tobacco genome through Southern blot analysis. Western blot result indicated that two types of PME protein existed in tobacco. But Northern hybridization detected only a full length transcript of PME, which further identified that there was post-translational process. Yeast two-hybrid result demonstrated that PME could not interact with the identified movement protein of rice dwarf virus (RDV), Pns6, but does interact with Pnsl1, a nucleic acid binding protein of RDV. It implies Pns11 may participate in the movement of RDV.

  5. Asparaginase Erwinia chrysanthemi

    Science.gov (United States)

    Asparaginase Erwinia chrysanthemi is used with other chemotherapy medications to treat acute lymphocytic leukemia (ALL; a type of cancer ... of allergic reactions to medications similar to asparaginase Erwinia chrysanthemi such as (asparaginase [Elspar] or pegaspargase [Oncaspar]). ...

  6. Cloning and Characterization of a Pectin Methylesterase Gene BrPME1 in Chinese Cabbage%大白菜果胶甲酯酶基因BrPME1的克隆及特征分析

    Institute of Scientific and Technical Information of China (English)

    刘志勇; 李承彧; 叶雪凌; 王晓霞; 冯辉

    2011-01-01

    [ Objective ] This paper aims at cloning a pectin methylesterase gene in order to provide assistance to study the roles of the pectin metabolism in the fertility regulation of Chinese cabbage. [Method] Analysis of gene differential expression was performed by cDNA-AFLP in the genic male sterile line 'AB02'of Chinese cabbage, and a differentially expressed cDNA fragment,TDF-24, was found only in fertile plants. The full-length cDNA of the gene related to TDF-24 was amplified by RACE and RT-PCR,and the characteristics of the deduced protein were analyzed using bioinformatics softwares. Gene expression characteristics were proved by Real-time PCR [Result] The novel pectin methylesterase (PME, EC 3.1.1.11) cDNA(BrPME1, GenBank accession number HM 185497), was isolated from Chinese cabbage. The cDNA was 1 290 bp long, encoding a putative preprotein of 363 amino acids with a signal peptide of 23 amino acids, which contains ten phosphorylation sites, six N-myristoylation site, one amidation site and one conserved PME domain, but no PMEI (pectin methylesterase inhibitor) site. BrPME1 was highly expressed in big flower buds and mature anthers of fertile plants, with an extremely low expression level in sterile buds. [ Conclusion ] The results indicated that BrPME1 is a member of the PME gene family inhibited by genic male sterile gene in Chinese cabbage.%[目的]克隆大白菜果胶甲酯酶基因,为进一步探讨果胶代谢在大白菜育性调控中的分子机制提供帮助.[方法]利用cDNA-AFLP技术分析大白菜核雄性不育两用系'AB02'可育株(msms)和不育株(Msms)花蕾的基因表达谱,在可育株混合花蕾cDNA中扩增出1条特异条带TDF-24,通过RACE技术扩增该基因的cDNA全长序列,采用生物信息学软件分析所克隆基因的编码蛋白特性,利用荧光定量PCR技术分析基因时空表达模式.[结果]该基因编码大白菜果胶甲酯酶(EC 3.1.1.11),被命名为BrPME1(GenBank登录号:HM185497).BrPME1

  7. Microscopic evidence for Ca(2+) mediated pectin-pectin interactions in carrot-based suspensions.

    Science.gov (United States)

    Kyomugasho, Clare; Willemsen, Katleen L D D; Christiaens, Stefanie; Van Loey, Ann M; Hendrickx, Marc E

    2015-12-01

    This study explored the use of fluorescently labeled pectin to obtain evidence for Ca(2+) mediated pectin-pectin interactions in situ. Specifically, carrots were either blanched at low temperature (LTB) or blanched at high temperature (HTB) to activate or inactivate endogenous pectin methylesterase, respectively. Consequently, pectin in tissue particles of LTB and HTB carrots exhibited low degree of methylesterification (DM) and high DM, respectively. Pectin present in the LTB carrot serum exhibited a lower DM, was more branched, and showed a higher molar mass compared to HTB carrot serum pectin. Ca(2+) mediated pectin-pectin interactions were influenced by serum pectin molecular structure, increased with increasing pH and Ca(2+) concentration, and decreasing DM. Presence of more linear pectin in the serum created a competition, leading to less intense interactions between labeled pectin and pectin at tissue particle surfaces. Generally, the most intense Ca(2+) mediated pectin-pectin interactions were observed for pectin of LTB carrot particles.

  8. 热处理对苹果果胶甲酯酶和多酚氧化酶活性影响%Effect of thermal treatment on the activity of apple pectin methylesterase and polyphenoloxidase

    Institute of Scientific and Technical Information of China (English)

    廖小军; 徐增慧; 智先

    2009-01-01

    研究了添加抗坏血酸对苹果浊汁中果胶甲酯酶(pectin methylesterase,PME)和多酚氧化酶活性(polyphenoloxidase,PPO)热钝化效果影响以及分析了PME热钝化动力学,结果表明,添加0.1%抗坏血酸(ascorbic acid,Vc)显著提高了苹果浊汁中PME和PPO活性以及热稳定性.95 ℃加热10 min后,PME和PPO活性下降了73.38%和94.10%,PME的热稳定性显著高于PPO.两段式一级反应动力学能较好拟合PME热钝化动力曲线,表明苹果浊汁中PME存在敏感型和稳定型两类同工酶.随着温度升高,敏感型和稳定型同工酶指数递减时间DL和DS值下降,钝化速率常数kL和kS值增大,其活化能EaL和EaS分别为62.57和108.11 KJ/mol.

  9. 高压二氧化碳对桃果胶甲基酯酶活性的钝化效果与动力学研究%Inactivation Kinetics of Pectin Methylesterase from Peach under High Pressure Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    周林燕; 廖小军; 曹霞敏; 刘凤霞; 毕秀芳; 易建勇; 李淑荣

    2014-01-01

    采用高压二氧化碳技术(High Pressure Carbon Dioxide,HPCD)处理桃果胶甲基酯酶(Pectin Methylesterase,PME)粗酶液,分析了 HPCD 对粗酶液中 PME 的钝化效果及动力学,进一步比较了粗酶液和桃汁两种体系中 PME 对 HPCD 的敏感性。HPCD 对粗酶液中PME 具有较好的钝化效果,处理温度和压力的共同作用导致了 PME 活性降低,钝化动力学遵从一级动力学模型。随着处理压力和温度的提高,钝化速率逐渐增大,而指数递减时间则逐渐减小;在最优的处理条件(22 MPa、55℃)下,HPCD 钝酶的钝化速率和指数递减时间分别为0.4088 min-1和5.63 min。温度为55℃时 HPCD 钝酶的压力敏感指数为16.40 MPa,活化体积为-383.00 cm3/mol;压强为15 MPa 时 HPCD 钝酶的温度敏感指数为13.30℃,活化能为1845.86 kJ/mol。比较 HPCD 对桃汁和粗酶液中 PME 的钝化效果,发现 HPCD 处理16 min后(15 MPa、55℃),桃汁中 PME 残存酶活在80%左右,而粗酶液中 PME 活性已完全钝化,表明桃汁体系中存在保护 PME 活性的因素,有关机制需要进一步研究。%The inactivation of pectin methylesterase (PME)from peach in buffer and juice by high pres-sure carbon dioxide (HPCD)was investigated.PME in buffer is effectively inactivated by HPCD,their residual activity decreases with the increase of pressure and temperature.The residual activity of the PME exhibited a fast decrease after a prolonged treatment time;their inactivation kinetics is adequate-ly modeled by the first order kinetics model.With the increase of pressure and temperature,the kinetic rate constant increases and the decimal reduction time decreases for PME in buffer inactivated by HPCD.The Kinetic rate and the decimal reduction time are 0.408 8 min-1 and 5.63 min respectively at the optimal condition (22 MPa,55 ℃).The activation volume and the pressure sensitivity exponent of inactivation PME by HPCD at 55 ℃ are -383.00 cm3/mol and 1 6.40 MPa

  10. 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

    Directory of Open Access Journals (Sweden)

    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

  11. Pectin modifications and the role of pectin-degrading enzymes during postharvest softening of Jonagold apples.

    Science.gov (United States)

    Gwanpua, Sunny George; Van Buggenhout, Sandy; Verlinden, Bert E; Christiaens, Stefanie; Shpigelman, Avi; Vicent, Victor; Kermani, Zahra Jamsazzadeh; Nicolai, Bart M; Hendrickx, Marc; Geeraerd, Annemie

    2014-09-01

    This study aimed at understanding softening in Jonagold apple (Malus×domestica Borkh.) fruits, by investigating pectin modifications and the evolution of pectin-modifying enzymes during postharvest storage and ripening. Jonagold apples were harvested at commercial maturity and stored at different temperatures and controlled atmosphere conditions for 6 months, followed by exposure to ambient shelf life conditions (20 °C under air) for 2 weeks. The composition of the pectic material was analysed. Furthermore, the firmness and the ethylene production of the apples were assessed. Generally, the main changes in pectin composition associated with the loss of firmness during ripening in Jonagold apples were a loss of side chains neutral sugars, increased water solubility and decreased molar mass. Also, the activities of four important enzymes possibly involved in apple softening, β-galactosidase, α-arabinofuranosidase, polygalacturonase and pectin methylesterase, were measured. Pectin-related enzyme activities highly correlated with ethylene production, but not always with pectin modifications.

  12. The Construction of Antisense Expression Vector of Pectin Methylesterase Gene and its Transfer to Yali Pear (Pyrus bretschneideri Rehd.)%鸭梨果胶甲酯酶基因反义表达载体的构建及转化

    Institute of Scientific and Technical Information of China (English)

    李会宣; 许冬倩; 齐靖; 闫洪波; 李桂琴

    2014-01-01

    果胶酯酶(pectin methylesterase,PME)催化细胞壁中多聚半乳糖醛酸的脱甲酯化,可以降解植物细胞壁中的果胶多糖而与果实软化有关.本研究根据白梨果胶酯酶基因PcPME4的序列,设计一对含有特定酶切位点的特异性引物,以鸭梨(Pyrus bretschneideri Rehd.)cDNA为模板通过PCR扩增得到一段294bp的PME基因片段.将片段反向插入植物表达载体pBI121的CaMV35S启动子和NOS终止子之间,经限制性酶切分析和测序分析证明成功构建PME基因的反义表达载体pBI121-AsPME.将pBI121-AsPME电转化农杆菌EHA105,利用含pBI121-AsPME的农杆菌工程菌液侵染鸭梨外植体后于抗性培养基中诱导愈伤组织,获得的抗性愈伤组织经PCR初步检测含有反向PME基因片段,荧光定量PCR检测结果显示受侵染的愈伤组织中PME基因表达量降低,表明反向插入的PME基因片段起到了抑制内源基因表达的效果.

  13. Ziek en Zeer : Erwinia chrysanthemi in Amaryllidaceae

    NARCIS (Netherlands)

    Vink, P.

    2011-01-01

    In dit artikel een verslag van het onderzoek naar de gevoeligheid van narcissen voor de bacterie Erwinia chrysanthemi (tegenwoordig Dickeya dadantii). Uit een infectieproef is gebleken dat deze bacterie tijdens een reguliere bollenteelt in Lisse niet in staat was om narcisbollen aan te tasten. Toch

  14. 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.)

  15. Tissue specific localization of pectin-Ca²⁺ cross-linkages and pectin methyl-esterification during fruit ripening in tomato (Solanum lycopersicum.

    Directory of Open Access Journals (Sweden)

    Hiromi Hyodo

    Full Text Available Fruit ripening is one of the developmental processes accompanying seed development. The tomato is a well-known model for studying fruit ripening and development, and the disassembly of primary cell walls and the middle lamella, such as through pectin de-methylesterified by pectin methylesterase (PE and depolymerization by polygalacturonase (PG, is generally accepted to be one of the major changes that occur during ripening. Although many reports of the changes in pectin during tomato fruit ripening are focused on the relation to softening of the pericarp or the Blossom-end rot by calcium (Ca²⁺ deficiency disorder, the changes in pectin structure and localization in each tissues during tomato fruit ripening is not well known. In this study, to elucidate the tissue-specific role of pectin during fruit development and ripening, we examined gene expression, the enzymatic activities involved in pectin synthesis and depolymerisation in fruit using biochemical and immunohistochemical analyses, and uronic acids and calcium (Ca-bound pectin were determined by secondary ion-microprobe mass spectrometry. These results show that changes in pectin properties during fruit development and ripening have tissue-specific patterns. In particular, differential control of pectin methyl-esterification occurs in each tissue. Variations in the cell walls of the pericarp are quite different from that of locular tissues. The Ca-binding pectin and hairy pectin in skin cell layers are important for intercellular and tissue-tissue adhesion. Maintenance of the globular form and softening of tomato fruit may be regulated by the arrangement of pectin structures in each tissue.

  16. Tissue specific localization of pectin-Ca²⁺ cross-linkages and pectin methyl-esterification during fruit ripening in tomato (Solanum lycopersicum).

    Science.gov (United States)

    Hyodo, Hiromi; Terao, Azusa; Furukawa, Jun; Sakamoto, Naoya; Yurimoto, Hisayoshi; Satoh, Shinobu; Iwai, Hiroaki

    2013-01-01

    Fruit ripening is one of the developmental processes accompanying seed development. The tomato is a well-known model for studying fruit ripening and development, and the disassembly of primary cell walls and the middle lamella, such as through pectin de-methylesterified by pectin methylesterase (PE) and depolymerization by polygalacturonase (PG), is generally accepted to be one of the major changes that occur during ripening. Although many reports of the changes in pectin during tomato fruit ripening are focused on the relation to softening of the pericarp or the Blossom-end rot by calcium (Ca²⁺) deficiency disorder, the changes in pectin structure and localization in each tissues during tomato fruit ripening is not well known. In this study, to elucidate the tissue-specific role of pectin during fruit development and ripening, we examined gene expression, the enzymatic activities involved in pectin synthesis and depolymerisation in fruit using biochemical and immunohistochemical analyses, and uronic acids and calcium (Ca)-bound pectin were determined by secondary ion-microprobe mass spectrometry. These results show that changes in pectin properties during fruit development and ripening have tissue-specific patterns. In particular, differential control of pectin methyl-esterification occurs in each tissue. Variations in the cell walls of the pericarp are quite different from that of locular tissues. The Ca-binding pectin and hairy pectin in skin cell layers are important for intercellular and tissue-tissue adhesion. Maintenance of the globular form and softening of tomato fruit may be regulated by the arrangement of pectin structures in each tissue.

  17. Decreasing methylation of pectin caused by nitric oxide leads to higher aluminium binding in cell walls and greater aluminium sensitivity of wheat roots.

    Science.gov (United States)

    Sun, Chengliang; Lu, Lingli; Yu, Yan; Liu, Lijuan; Hu, Yan; Ye, Yiquan; Jin, Chongwei; Lin, Xianyong

    2016-02-01

    Nitric oxide (NO) is an important bioactive molecule involved in cell wall metabolism, which has been recognized as a major target of aluminium (Al) toxicity. We have investigated the effects of Al-induced NO production on cell wall composition and the subsequent Al-binding capacity in roots of an Al-sensitive cultivar of wheat (Triticum aestivum L. cv. Yang-5). We found that Al exposure induced NO accumulation in the root tips. Eliminating NO production with an NO scavenger (cPTIO) significantly alleviated the Al-induced inhibition of root growth and thus reduced Al accumulation. Elimination of NO, however, did not significantly affect malate efflux or rhizosphere pH changes under Al exposure. Levels of cell wall polysaccharides (pectin, hemicelluloses 1, and hemicelluloses 2) and pectin methylesterase activity, as well as pectin demethylation in the root apex, significantly increased under Al treatment. Exogenous cPTIO application significantly decreased pectin methylesterase activity and increased the degree of methylation of pectin in the root cell wall, thus decreasing the Al-binding capacity of pectin. These results suggest that the Al-induced enhanced production of NO decreases cell wall pectin methylation, thus increasing the Al-binding capacity of pectin and negatively regulating Al tolerance in wheat.

  18. The changes in pectin metabolism in flax infected with Fusarium.

    Science.gov (United States)

    Wojtasik, Wioleta; Kulma, Anna; Kostyn, Kamil; Szopa, Jan

    2011-08-01

    Fusarium culmorum and Fusarium oxysporum are the most common fungal pathogens of flax (Linum usitatissimum L.), thus leading to the greatest losses in crop yield. A subtractive cDNA library was constructed from flax seedlings exposed for two days to F. oxysporum. This revealed a set of genes that are potentially involved in the flax defense responses. Two of those genes directly participate in cell wall sugar polymer metabolism: UDP-D-glucuronate 4-epimerase (GAE; EC 5.1.3.6) and formate dehydrogenase (FDH; EC 1.2.1.2). GAE delivers the main substrate for pectin biosynthesis, and decreases were detected in its mRNA level after Fusarium infection. FDH participates in the metabolism of formic acid, and the expression level of its gene increased after Fusarium infection. However, metabolite profiling analysis disclosed that the pectin content in the infected plants remained unchanged, but that there were reductions in both the levels of the soluble sugars that serve as pectin precursors, and in the level of formic acid. Since formic acid is the product of pectin demethylesterification, the level of mRNAs coding for pectin methylesterase (EC 3.1.1.11) in the infected flax was measured, revealing a decrease in its expression upon plant infection. Transgenic flax plants overexpressing fungal polygalacturonase (EC 3.2.1.15) and rhamnogalacturonase (EC 3.2.1.-) showed a decrease in the pectin content and an elevated level of formic acid, but the level of expression of the FDH gene remained unchanged. It is suspected that the expression of the formate dehydrogenase gene is directly controlled by the pathogen in the early stage of infection, and additionally by pectin degradation in the later stages.

  19. Novel roles of hydrogen peroxide (H₂O₂) in regulating pectin synthesis and demethylesterification in the cell wall of rice (Oryza sativa) root tips.

    Science.gov (United States)

    Xiong, Jie; Yang, Yongjie; Fu, Guanfu; Tao, Longxing

    2015-04-01

    Hydrogen peroxide (H₂O₂) has been reported to increase lignin formation, enhance cell wall rigidification, restrict cell expansion and inhibit root elongation. However, our results showed that it not only inhibited rice (Oryza sativa) root elongation, but also increased root diameter. No study has reported how and why H₂O₂ increases cell expansion and root diameter. Exogenous H₂O₂ and its scavenger 4-hydroxy-Tempo were applied to confirm the roles of H₂O₂. Immunofluorescence, fluorescence probe, ruthenium red staining, histological section and spectrophotometry were used to monitor changes in the degree of pectin methylesterification, pectin content, pectin methylesterase (PME) activity and H₂O₂ content. Exogenous H₂O₂ inhibited root elongation, but increased cell expansion and root diameter significantly. H₂O₂ not only increased the region of pectin synthesis and pectin content in root tips, but also increased PME activity and pectin demethylesterification. The scavenger 4-hydroxy-Tempo reduced root H₂O₂ content and recovered H₂O₂-induced increases in cell expansion and root diameter by inhibiting pectin synthesis, PME activity and pectin demethylesterification. H₂O₂ plays a novel role in the regulation of pectin synthesis, PME activity and pectin demethylesterification. H₂O₂ increases cell expansion and root diameter by increasing pectin content and demethylesterification.

  20. A comparative genome analysis of PME and PMEI families reveals the evolution of pectin metabolism in plant cell walls.

    Science.gov (United States)

    Wang, Maojun; Yuan, Daojun; Gao, Wenhui; Li, Yang; Tan, Jiafu; Zhang, Xianlong

    2013-01-01

    Pectins are fundamental polysaccharides in the plant primary cell wall. Pectins are synthesized and secreted to cell walls as highly methyl-esterified polymers and then demethyl-esterified by pectin methylesterases (PMEs), which are spatially regulated by pectin methylesterase inhibitors (PMEIs). Although PME and PMEI genes are pivotal in plant cell wall formation, few studies have focused on the evolutionary patterns of the PME and PMEI gene families. In this study, the gene origin, evolution, and expression diversity of these two families were systematically analyzed using 11 representative species, including algae, bryophytes, lycophytes and flowering land plants. The results show that 1) for the two subfamilies (PME and proPME) of PME, the origin of the PME subfamily is consistent with the appearance of pectins in early charophyte cell walls, 2) Whole genome duplication (WGD) and tandem duplication contribute to the expansion of proPME and PMEI families in land plants, 3) Evidence of selection pressure shows that the proPME and PMEI families have rapidly evolved, particularly the PMEI family in vascular plants, and 4) Comparative expression profile analysis of the two families indicates that the eudicot Arabidopsis and monocot rice have different expression patterns. In addition, the gene structure and sequence analyses show that the origin of the PMEI domain may be derived from the neofunctionalization of the pro domain after WGD. This study will advance the evolutionary understanding of the PME and PMEI families and plant cell wall development.

  1. Cobtorin target analysis reveals that pectin functions in the deposition of cellulose microfibrils in parallel with cortical microtubules.

    Science.gov (United States)

    Yoneda, Arata; Ito, Takuya; Higaki, Takumi; Kutsuna, Natsumaro; Saito, Tamio; Ishimizu, Takeshi; Osada, Hiroyuki; Hasezawa, Seiichiro; Matsui, Minami; Demura, Taku

    2010-11-01

    Cellulose and pectin are major components of primary cell walls in plants, and it is believed that their mechanical properties are important for cell morphogenesis. It has been hypothesized that cortical microtubules guide the movement of cellulose microfibril synthase in a direction parallel with the microtubules, but the mechanism by which this alignment occurs remains unclear. We have previously identified cobtorin as an inhibitor that perturbs the parallel relationship between cortical microtubules and nascent cellulose microfibrils. In this study, we searched for the protein target of cobtorin, and we found that overexpression of pectin methylesterase and polygalacturonase suppressed the cobtorin-induced cell-swelling phenotype. Furthermore, treatment with polygalacturonase restored the deposition of cellulose microfibrils in the direction parallel with cortical microtubules, and cobtorin perturbed the distribution of methylated pectin. These results suggest that control over the properties of pectin is important for the deposition of cellulose microfibrils and/or the maintenance of their orientation parallel with the cortical microtubules.

  2. Two-step enzymatic fingerprinting of sugar beet pectin.

    Science.gov (United States)

    Remoroza, C; Broxterman, S; Gruppen, H; Schols, H A

    2014-08-01

    A two-step enzymatic fingerprinting method was introduced to analyze a highly methylesterified and acetylated sugar beet pectin having a degree of methylesterification (DM) of 62 and acetylation of 30. A cocktail of pectolytic enzymes, including endo-polygalacturonase II (endo-PGII) and pectin lyase (PL), was used for the first digestion. The endo-PGII and PL resistant pectin fragments were isolated and subjected to a second digestion using fungal pectin methylesterase and endo-PGII. After the two sequential digestions, 78% of the total GalA residues present in the parental pectin were recovered as mono- and oligomers, which were used to quantitatively describe the parental SBP. For this reason, the descriptive parameters degree of blockiness (DBabs), degree of hydrolysis by PG (DHPG) and degree of hydrolysis by PL (DHPL) were established for both digestions. The first digestion revealed the presence of short blocks of nonesterified GalA residues and blocks of partly methylesterified and acetylated GalA residues in the parental SBP, in addition to blocks of highly methylesterified and acetylated GalA residues. The second digestion revealed the presence of blocks of methylesterified, partly methylesterified and/or acetylated GalA residues in a sequence not to be degradable by neither endo-PGII nor by PL. The acetyl groups were present in an blockwise manner. Application of the method to two differently prepared DM 50 SBPs showed that the two pectins differ in the ratio of blocks of nonesterified and blocks of partly methylesterified and acetylated GalA residues.

  3. Pectin modifications: a review.

    Science.gov (United States)

    Chen, Jun; Liu, Wei; Liu, Cheng-Mei; Li, Ti; Liang, Rui-Hong; Luo, Shun-Jing

    2015-01-01

    In recent years, the interest in studying modification of pectin has increased. A number of hydroxyl and carboxyl groups distributed along the backbone as well as a certain amount of neutral sugars presented as side chains make pectin capable of preparing a broad spectrum of derivatives. By forming pectin derivatives, their properties may be modified and some other new functional properties may be created. This article attempts to review the information about various methods used for pectin modification, including substitution (alkylation, amidation, quaternization, thiolation, sulfation, oxidation, etc.), chain elongation (cross-linking and grafting) and depolymerization (chemical, physical, and enzymatic degradation). Characteristics and applications of some pectin derivatives are also presented. In addition, the safety and regulatory status of pectin and its derivatives were reviewed.

  4. Simplified Extraction and Cleanup for Multiresidue Determination of Pyrethroid Insecticides in Chrysanthemi

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A simplified method for determining 4 pyrethroid insecticides (Fenpropathrin,Cypermethrin,Fenvalirate,and Deltamethrin)in Chrysanthemi is described.Standards were fortified in to Chrysanthemi (5g)with two levels,)0.1-1ppm the pyrethroid pesticides are extracted with petroleum ether and cleaned up by natural aluminum oxide.The extracts are analyzed by gas chromatography equipped with electron capture detector (ECD).Analysis of fortified Chrysanthemi(n=3)shows recovery range from 99-102% at 1 ppm level and 93-104% at 0.1 ppm level. The coefficient of variation of the method at 1st level was 0.12 and 0.14 for 2ed level.The detection limits of the method ranged from 0.04ppb to 28ppb.The method is repid,sample,and sensitive and is applicable to the determination of Fenpropathrin,Cypermethrin,Fenvalirate,and Deltamethrin in Chrysanthemi.

  5. The Structure of Pectin

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Biosynthesis of pectin

    DEFF Research Database (Denmark)

    Scheller, Henrik Vibe; Jensen, Jacob Krüger; Sørensen, Susanne Oxenbøll

    2007-01-01

    Pectin consists of a group of acidic polysaccharides that constitute a large part of the cell wall of plants. The pectic polysaccharides have a complex structure but can generally be divided into homogalacturonan, rhamnogalacturonan I, rhamnogalacturonan II (RGII) and xylogalacturonan (XGA......). These polysaccharides appear to be present in all cells but their relative abundance and structural details differ between cell types and species. Pectin is synthesized in the Golgi vesicles and its complexity dictates that a large number of enzymes must be involved in the process. The biosynthetic enzymes required...... are glycosyltransferases and decorating enzymes including methyltransferases, acetyltransferases and feruloyltransferases. Biochemical methods successfully led to the recent identification of a pectin biosynthetic galacturonosyltransferase (GAUT1), and recent functional genomics and mutant studies have allowed...

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

    Science.gov (United States)

    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.

  8. 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 electroph

  9. Determination of camphor and borneol in Flos Chrysanthemi Indici by UAE and GC-FID.

    Science.gov (United States)

    Ye, Qing; Deng, Chunhui

    2009-04-01

    In the work, ultrasonic-assisted extraction (UAE) followed by gas chromatography with flame ionization detector (GC-FID) is developed for the quantitative analysis of the bioactive components of camphor and borneol in a traditional Chinese medicine (TCM) of Flos Chrysanthemi Indici. The extraction parameters are investigated. The optimum extraction conditions found are: solvent, methanol; solvent to sample ratio, 12:1 (v/w); extraction time, 15 min. Camphor and borneol are determined using this extraction method in Flos Chrysanthemi Indici samples from 5 different growing areas. The relative standard deviation values for camphor and borneol are 8.4% and 5.6%, respectively. The recoveries for camphor and borneol are 89% and 95%, respectively, and the method detection limits are lower than 0.23 microg/mL. To demonstrate the method feasibility, steam distillation is also used to analyze camphor and borneol in Flos Chrysanthemi Indici samples from these different growing areas. The statistical comparison by t-test (95% confidence level) showed no significant difference between these results. It has been shown that the proposed UAE-GC-FID is a simple, rapid, and reliable method for quantitative analysis of camphor and borneol in TCM, and a potential tool for quality assessment of Flos Chrysanthemi Indici.

  10. Reactive oxygen species activity in the interaction of rice with Erwinia chrysanthemi pv. zeae

    Institute of Scientific and Technical Information of China (English)

    Qiongguang LIU; Landi HE; Jingyi ZHANG; Yutao WANG; Zhenzhong WANG

    2008-01-01

    Activities of reactive oxygen species (ROS) were investigated in the interaction between rice and Erwinia chrysanthemi pv. zeae. Results showed that variety (128) had higher increases in activity compared to those in the susceptible variety (Texian 13) 24 hours after bacteria inoculation. The activities of superoxide dismutase (SOD) increased in 128 and Texian 13 twenty-four hours after inoculation and then decreased, but the SOD activity in 128 was found to be usually lower than that in Texian 13. The CAT activity in Texian 13 had two peaks at 24 h and 96 h after inoculation, while little change was seen in 128. In conclusion, ROS and its related enzymes could be correlated to rice resistance against E. chrysanthemi pv. zeae.

  11. Pectins, Endopolygalacturonases, and Bioenergy

    Science.gov (United States)

    Latarullo, Mariana B. G.; Tavares, Eveline Q. P.; Maldonado, Gabriel P.; Leite, Débora C. C.; Buckeridge, Marcos S.

    2016-01-01

    The precise disassembly of the extracellular matrix of some plant species used as feedstocks for bioenergy production continues to be a major barrier to reach reasonable cost effective bioethanol production. One solution has been the use of pretreatments, which can be effective, but increase even more the cost of processing and also lead to loss of cell wall materials that could otherwise be used in industry. Although pectins are known to account for a relatively low proportion of walls of grasses, their role in recalcitrance to hydrolysis has been shown to be important. In this mini-review, we examine the importance of pectins for cell wall hydrolysis highlighting the work associated with bioenergy. Here we focus on the importance of endopolygalacturonases (EPGs) discovered to date. The EPGs cataloged by CAZy were screened, revealing that most sequences, as well as the scarce structural work performed with EPGs, are from fungi (mostly Aspergillus niger). The comparisons among the EPG from different microorganisms, suggests that EPGs from bacteria and grasses display higher similarity than each of them with fungi. This compilation strongly suggests that structural and functional studies of EPGs, mainly from plants and bacteria, should be a priority of research regarding the use of pectinases for bioenergy production purposes. PMID:27703463

  12. Structural characterization of native pectins

    NARCIS (Netherlands)

    Coenen, G.J.

    2007-01-01

    Pectine wordt in levensmiddelen vooral gebruikt als geleermiddel, stabilisator of verdikkingsmiddel in producten zoals jam, yoghurtdranken, vruchten-zuiveldranken en ijs. Daarnaast is er in toenemende mate interesse in het mogelijk gezondheidbevorderend effect van dit polysaccharide. Kennis van de e

  13. 21 CFR 184.1588 - Pectins.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Pectins. 184.1588 Section 184.1588 Food and Drugs... Substances Affirmed as GRAS § 184.1588 Pectins. (a) The pectins (CAS Reg. No. 9000-69-5) are a group of... Reg. No. 9000-59-8) salts, and in some types as the acid amide. Thus, the pectins regulated in...

  14. A multiplex real-time PCR assay for the detection of Puccinia horiana and P. chrysanthemi on chrysanthemum

    Science.gov (United States)

    Puccinia horiana, the cause of chrysanthemum white rust, is a regulated fungal plant pathogen in the United States, while Puccinia chrysanthemi, the cause of chrysanthemum brown rust, is a widespread but less destructive pathogen. Accurate identification of these pathogens is essential to correctly ...

  15. PECTIN BEVERAGES WITH PROBIOTIC CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    Ogneva O. A.

    2015-03-01

    Full Text Available The impact of pectins and its concentration on probiotic characteristics of the beverages has been studied for developing the formulation and technology of pectin beverages. Samples of sour-milk products with dry pectin (Unipectin OB 700 and liquid one (pectin apple extract is produced by SunLand was made. Sour milk microorganisms and bifidobacteria content were defined. High sour milk microorganisms and bifidobacteria content as well as high rate in souring were revealed in the preparatory samples. However, liquid pectin is easier in use. Consequently, the formulation of pectin extract beverages was developed and optimized by using Mathematical Modeling. The samples of beverages were produced and their quality characteristics were evaluated. An optimal fruit/vegetable fillers / whey ration was defined to get the product which combined balanced micronutrient composition, its functional activities and gustatory qualities. For that a three-factor simplex-centroid design was used. The samples produced according to the design matrix were tasted and evaluated by color, flavor, aroma and consistency according to the ten score points scale. The findings were processed with statistical and graphical analysis. The last one used the construction of ternary graphs with the help of «Statistica 7,0» program that allowed to define the most acceptable ranges of fruit/vegetable fillers / whey components in the beverages: fruit juice – 4-16%; pumpkin juice-4-16%; whey -4%. Chemical composition, organoleptical indicators and physicochemical parameters of ready-to drink beverages were examined. As a result, these beverages have been recommended for school feeding as the source of dietary fiber, minerals and vitamins

  16. Isolation, characterization and modification of citrus pectins

    Directory of Open Access Journals (Sweden)

    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.

  17. Biodegradable Pectin/clay Aerogels

    Science.gov (United States)

    Biodegradable, foamlike materials based on renewable pectin and sodium montmorillonite clay were fabricated through a simple, environmentally friendly freeze-drying process. Addition of multivalent cations (Ca2+ and Al3+) resulted in apparent crosslinking of the polymer, and enhancement of aerogel p...

  18. The acyl-homoserine lactone-type quorum-sensing system modulates cell motility and virulence of Erwinia chrysanthemi pv. zeae.

    Science.gov (United States)

    Hussain, Mumtaz B B M; Zhang, Hai-Bao; Xu, Jin-Ling; Liu, Qiongguang; Jiang, Zide; Zhang, Lian-Hui

    2008-02-01

    Erwinia chrysanthemi pv. zeae is one of the Erwinia chrysanthemi pathovars that infects on both dicotyledons and monocotyledons. However, little is known about the molecular basis and regulatory mechanisms of its virulence. By using a transposon mutagenesis approach, we cloned the genes coding for an E. chrysanthemi pv. zeae synthase of acyl-homoserine lactone (AHL) quorum-sensing signals (expI(Ecz)) and a cognate response regulator (expR(Ecz)). Chromatography analysis showed that expI(Ecz) encoded production of the AHL signal N-(3-oxo-hexanoyl)-homoserine lactone (OHHL). Null mutation of expI(Ecz) in the E. chrysanthemi pv. zeae strain EC1 abolished AHL production, increased bacterial swimming and swarming motility, disabled formation of multicell aggregates, and attenuated virulence of the pathogen on potato tubers. The mutation also marginally reduced the inhibitory activity of E. chrysanthemi pv. zeae on rice seed germination. The mutant phenotypes were rescued by either exogenous addition of AHL signal or in trans expression of expI(Ecz). These data demonstrate that the AHL-type QS signal plays an essential role in modulation of E. chrysanthemi pv. zeae cell motility and the ability to form multicell aggregates and is involved in regulation of bacterial virulence.

  19. Tol-Pal proteins are critical cell envelope components of Erwinia chrysanthemi affecting cell morphology and virulence.

    Science.gov (United States)

    Dubuisson, Jean-François; Vianney, Anne; Hugouvieux-Cotte-Pattat, Nicole; Lazzaroni, Jean Claude

    2005-10-01

    The tol-pal genes are necessary for maintaining the outer-membrane integrity of Gram-negative bacteria. These genes were first described in Escherichia coli, and more recently in several other species. They are involved in the pathogenesis of E. coli, Haemophilus ducreyi, Vibrio cholerae and Salmonella enterica. The role of the tol-pal genes in bacterial pathogenesis was investigated in the phytopathogenic enterobacterium Erwinia chrysanthemi, assuming that this organism might be a good model for such a study. The whole Er. chrysanthemi tol-pal region was characterized. Tol-Pal proteins, except TolA, showed high identity scores with their E. coli homologues. Er. chrysanthemi mutants were constructed by introducing a uidA-kan cassette in the ybgC, tolQ, tolA, tolB, pal and ybgF genes. All the mutants were hypersensitive to bile salts. Mutations in tolQ, tolA, tolB and pal were deleterious for the bacteria, which required high concentrations of sugars or osmoprotectants for their viability. Consistent with this observation, they were greatly impaired in their cell morphology and division, which was evidenced by observations of cell filaments, spherical forms, membrane blebbing and mislocalized bacterial septa. Moreover, tol-pal mutants showed a reduced virulence in a potato tuber model and on chicory leaves. This could be explained by a combination of impaired phenotypes in the tol-pal mutants, such as reduced growth and motility and a decreased production of pectate lyases, the major virulence factor of Er. chrysanthemi.

  20. SecG is required for antibiotic activities of Pseudomonas sp. YL23 against Erwinia amylovora and Dickeya chrysanthemi.

    Science.gov (United States)

    Liu, Youzhou; Baird, Sonya M; Qiao, Junqing; Du, Yan; Lu, Shi-En

    2015-05-01

    Strain YL23 was isolated from soybean root tips and identified to be Pseudomonas sp. This strain showed broad-spectrum antibacterial activity against bacterial pathogens that are economically important in agriculture. To characterize the genes dedicated to antibacterial activities against microbial phytopathogens, a Tn5-mutation library of YL23 was constructed. Plate bioassays revealed that the mutant YL23-93 lost its antibacterial activities against Erwinia amylovora and Dickeya chrysanthemi as compared with its wild type strain. Genetic and sequencing analyses localized the transposon in a homolog of the secG gene in the mutant YL23-93. Constitutive expression plasmid pUCP26-secG was constructed and electroporated into the mutant YL23-93. Introduction of the plasmid pUCP26-secG restored antibacterial activities of the mutant YL23-93 to E. amylovora and D. chrysanthemi. As expected, empty plasmid pUCP26 could not complement the phenotype of the antibacterial activity in the mutant. Thus the secG gene, belonging to the Sec protein translocation system, is required for antibacterial activity of strain YL23 against E. amylovora and D. chrysanthemi.

  1. Apple Pectin Behavior Separated by Ultrafiltration

    Institute of Scientific and Technical Information of China (English)

    QIU Nong-xue; TIAN Yu-xia; QIAO Shu-tao; DENG Hong

    2009-01-01

    Separation conditions of ultrafiltration for apple pectin, and relations between apple pectin with different relative molecular weights and their structures and properties are studied. Five kinds of ultrafiltration membranes with different molecular weight cut-offs are used to separate apple pectin. FT-IR and HPGC are used individually to determine the structures and monosaccharide composition of apple pectin with different relative molecular weights. In the case of transmembrane pressure difference of 0.08 MPa, material concentration of 1 g L-1, and temperature of 50℃, 6 kinds of apple pectins with different molecular weights have been obtained. Molecular weight of apple pectin is correspondingly related to its physicochemical properties. The galacturonic acid contents and esterification and gelatination degrees increase relatively with an increase in molecular weight, and the monosaccharide composition relatively increase much more. And at the same time, the ultrafiltratiou has a better role to play in decoloring apple pectin solution. Accordingly, this research can be used as a new method for in-depth exploration of apple pectin.

  2. 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...

  3. A novel perspective on pectin extraction

    DEFF Research Database (Denmark)

    Dominiak, Malgorzata Maria

    The classical (current) extraction of pectin is based on an acid-catalyzed process, using nitric, hydrochloric or sulphuric acid. The reaction takes place at low pH and high temperatures for several hours. The main disadvantage of this technology, and one which raises environmental concerns......, is generation of large volumes of acidic effluent, which require further treatment before release. The main focus of this PhD study was to replace acid with enzymes and thereby achieve sustainable, green production of pectin. The first goal was to prove that an enzyme-based process could generate pectin...... with pectins obtained in a classical way. In the future it would be beneficial to optimize the Laminex C2K production strain (Penicillium funiculosum) by molecular design to delete the residual pectinolytic activity and include plant cell wall hydrolases. Pectin production is complex and therefore its...

  4. A New Approach to Pectin Manufacture by Copper Method : Part 2. Preparation of Dry Metal-Pectin Complex

    OpenAIRE

    Kausar, Pervez; Nomura, Danji

    1981-01-01

    This study was part of an attempt to develop a disintegrated pectin manufacture process to utilize to its maximum already existing facilities at citrus juice plants as well as to cut down the energy and transport costs by maximum using the wet leached peel and transporting dry metal-pectin complex to a central pectin manufacture plant for further processing instead of transporting huge volume of pectin pomace. This type of approach was thought essential to prepare cost wise competiable pectin...

  5. Aqueous extraction of pectin from sisal waste.

    Science.gov (United States)

    Santos, Jener David G; Espeleta, Alexandre F; Branco, Alexsandro; de Assis, Sandra A

    2013-02-15

    In this work, sisal waste was used as a source of pectin. Sisal is known worldwide as a source of hard fibres, and Brazil is the largest producer of sisal, producing more than 246,000 tonnes. However, the process of removing the fibres of the sisal leaf generates 95% waste. This study investigated the effect of the liquid/solid ratio (%), time (min), and temperature (°C) on the yield of the pectin obtained from sisal waste by attractive environmentally friendly process. A statistical Box-Behnken design was applied to determine the important effects and interactions of these independent variables on the yield of pectin, the dependent variable. Significant models were obtained. The yield of the extracted pectin ranged from 4.61 to 19.2%. The conditions that produced the highest yield (19.2%) were a temperature of 85 °C, extraction time of 60 min and a liquid/solid ratio of 2%.

  6. Characteristics, Enzymatic Extraction of Pectin from Shaddock

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Pectins had been extracted from shaddock raw material with 0.01 mol·L-1 HGl and with three enzymic preparations including cellulase from aspergillus oryzaei, β -glucosidase from almonds and protopectinases-T, a protopectin-solubilizing enzyme, which did not degrade polygalacturonic acid. The effects of enzymic and acid soluhilization of pectin from shaddock materials were compared. The yield of pectin preparations, degree of acetylation, gelling strength, molecular weight and viscosity were determined. Enzymic methods of extraction gave much bigger yields of pectic substances. Compared with the pectin extracted with hydrochloric acid, all the samples derived from shaddock raw material with enzymic preparations had a significant lower D-galacturonic acid content.

  7. Pectin functionalized with natural fatty acids as antimicrobial agent.

    Science.gov (United States)

    Calce, Enrica; Mignogna, Eleonora; Bugatti, Valeria; Galdiero, Massimiliano; Vittoria, Vittoria; De Luca, Stefania

    2014-07-01

    Several pectin derivatives were prepared by chemical modifications of the polysaccharide with natural fatty acids. The obtained biodegradable pectin-based materials, pectin-linoleate, pectin-oleate and pectin-palmitate, were investigated for their antimicrobial activity against several bacterial strains, Staphylococcus aureus and Escherichia coli. Good results were obtained for pectin-oleate and pectin-linoleate, which inhibit the growth of the selected microorganisms by 50-70%. They exert the better antimicrobial activity against S. aureus. Subsequently, the pectin-oleate and the pectin-linoleate samples were coated on polyethylene films and were assessed for their capacity to capture the oxygen molecules, reducing its penetration into the polymeric support. These results confirmed a possible application of the new materials in the field of active food packaging.

  8. Radiation sensitivity of different citric pectins

    Energy Technology Data Exchange (ETDEWEB)

    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)

  9. Elaborate spatial patterning of cell-wall PME and PMEI at the pollen tube tip involves PMEI endocytosis, and reflects the distribution of esterified and de-esterified pectins.

    Science.gov (United States)

    Röckel, Nina; Wolf, Sebastian; Kost, Benedikt; Rausch, Thomas; Greiner, Steffen

    2008-01-01

    In dicots, pectins are the major structural determinant of the cell wall at the pollen tube tip. Recently, immunological studies revealed that esterified pectins are prevalent at the apex of growing pollen tubes, where the cell wall needs to be expandable. In contrast, lateral regions of the cell wall contain mostly de-esterified pectins, which can be cross-linked to rigid gels by Ca(2+) ions. In pollen tubes, several pectin methylesterases (PMEs), enzymes that de-esterify pectins, are co-expressed with different PME inhibitors (PMEIs). This raises the possibility that interactions between PMEs and PMEIs play a key role in the regulation of cell-wall stability at the pollen tube tip. Our data establish that the PME isoform AtPPME1 (At1g69940) and the PMEI isoform AtPMEI2 (At3g17220), which are both specifically expressed in Arabidopsis pollen, physically interact, and that AtPMEI2 inactivates AtPPME1 in vitro. Furthermore, transient expression in tobacco pollen tubes revealed a growth-promoting activity of AtPMEI2, and a growth-inhibiting effect of AtPPME1. Interestingly, AtPPME1:YFP accumulated to similar levels throughout the cell wall of tobacco pollen tubes, including the tip region, whereas AtPMEI2:YFP was exclusively detected at the apex. In contrast to AtPPME1, AtPMEI2 localized to Brefeldin A-induced compartments, and was found in FYVE-induced endosomal aggregates. Our data strongly suggest that the polarized accumulation of PMEI isoforms at the pollen tube apex, which depends at least in part on local PMEI endocytosis at the flanks of the tip, regulates cell-wall stability by locally inhibiting PME activity.

  10. Citrus pectin: structure and application in acid dairy drinks

    OpenAIRE

    Tanhatan Naseri, Abrisham; Thibault, Jean-François

    2008-01-01

    Pectin, a plant cell wall polysaccharide, is mainly used in food industries for its gelling and stabilizing properties. In industrial applications, pectin is usually widely extracted from citrus peels, and in some intances, apple pomace is also used. Lime and lemon are the preferred citrus species used in the extraction of pectin, while orange and grapefruit are used less often. In the food industry, pectin is widely employed in the production of jams and jellies, confectionary products a...

  11. New, hybrid pectin-based biosorbents

    Science.gov (United States)

    Jakóbik-Kolon, Agata; Milewski, Andrzej K.; Karoń, Krzysztof; Bok-Badura, Joanna

    2016-01-01

    ABSTRACT In this work hybrid pectin-based biosorbents with secondary polysaccharide additives (gellan, carob and xanthan gum, ratio to pectin 1:1, 1:1 and 1:3, respectively) were obtained at two temperatures. The presence of these additives in prepared beads was confirmed by Raman spectra. The SEM micrographs show better homogeneity of blends and grater differences between structures of beads with various additives obtained at higher temperature. The sorption capacity of our hybrid biosorbents as well as sole pectin sorbent is rather the same, and equals 0.85 and 0.70 mmol/g for lead and cadmium, respectively, in pH 4–6. PMID:27812233

  12. Erwinia chrysanthemi: pectolytic bacterium causing soft rot outbreaks of arracacha in Brazil Erwinia chrysanthemi: bactéria pectolítica envolvida na "mela" da mandioquinha-salsa no Brasil

    Directory of Open Access Journals (Sweden)

    Gilmar Paulo Henz

    2006-10-01

    Full Text Available The objetive of this work was to identify the pectolytic bacteria associated with soft rot of arracacha roots in Brazil. From 1998 to 2001, 227 isolates of Erwinia spp. were obtained from arracacha roots and identified by biochemical and physiological tests (pectolytic activity, lecithinase, a-methyl glucoside, phosphatase, erythromycin sensivity, growth at 37ºC. Of these isolates, 89.9% were identified as E. chrysanthemi (Ech, 9.7% as E. carotovora subsp. carotovora (Ecc and 0.5% as E. carotovora subsp. atroseptica. The identity of seventeen out of twenty representative isolates of Ech and Ecc was confirmed by PCR (primers '149f', 'L1r', 'ADE1', 'ADE2'.O objetivo deste trabalho foi identificar as bactérias pectolíticas envolvidas na podridão-mole de raízes de mandioquinha-salsa no Brasil. De 1998 a 2001, 227 isolados de Erwinia spp. foram obtidos de raízes de mandioquinha-salsa e identificados por testes bioquímicos e fisiológicos (atividade pectolítica, lecitinase, a-methyl glucosídeo, fosfatase, sensibilidade à eritromicina, crescimento a 37ºC. Destes isolados, 89,9% foram identificados como E. chrysanthemi (Ech, 9,7% como E. carotovora subsp. carotovora (Ecc e somente 0,5% como E. carotovora subsp. atroseptica. A identidade de 20 isolados representativos de Ech e Ecc foi confirmada por PCR (primers '149f', 'L1r', 'ADE1', 'ADE2', com exceção de dois isolados de Ech e um de Ecc.

  13. Novel modified pectin for heavy metal adsorption

    Institute of Scientific and Technical Information of China (English)

    Feng Ting Li; Hong Yang; Yan Zhao; Ran Xu

    2007-01-01

    Modified pectin cross-linked with adipic acid, was synthesized and used for heavy metal removal from wastewater. SEM and FrIR were used to investigate its structure and morphology. The modified pectin had a rough, porous phase covered with carboxy groups, resulting a high adsorption capacity. And at the room temperature, the saturated loading capacity for Pb2+, Cu2+ and Zn2+ reached 1.82 mmol/g, 1.794 mmol/g and 0.964 mmol/g, respectively. The results proved its potential application to remove of the heavy metal.

  14. Chitosan-Pectin Synergistic Interaction and Gelation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Mixed gels of chitosan-pectin were prepared by varying the ratio of constituents in the presence of NaCl. Mixed gel at 3% of total polysaccharide concentration with addtion of 12% NaCl showed a synergistic maximum when the ratio of chitosan to pectin was 60 : 40. The effect of the polysaccharide concentration,the preparation temperature(Tp), the time of incubation, balk salt concentration, the molecular weight and the degree of deacetylation of chitosan on gelation have been studied. Interaction mechanism between molecules of both polysaccharides was investigated by FT-IR spectrometry.

  15. Asparaginase Erwinia chrysanthemi (Erwinaze®): a guide to its use in acute lymphoblastic leukemia in the USA.

    Science.gov (United States)

    Keating, Gillian M

    2013-08-01

    Asparaginase Erwinia chrysanthemi (Erwinaze®) is approved in the USA for use in patients with acute lymphoblastic leukemia (ALL) who have developed hypersensitivity to Escherichia coli-derived asparaginase. The approved regimen of intramuscular Erwinaze® was associated with sustained, clinically meaningful asparaginase activity in patients with ALL who had to discontinue treatment with pegaspargase (a pegylated formulation of E. coli asparaginase) because of hypersensitivity. Another study revealed that development of E. coli-derived asparaginase allergy and a switch to Erwinaze® maintained event-free survival in pediatric patients with newly diagnosed ALL. In a multicenter, compassionate-use trial, Erwinaze® was generally well tolerated, with the most commonly occurring adverse events including hypersensitivity, pancreatitis, fever, hyperglycemia, and increased transaminase levels. Subclinical hypersensitivity may result in the inactivation of asparaginase and affect treatment outcome; monitoring of serum asparaginase levels may be used to identify subclinical hypersensitivity.

  16. 菊欧文氏菌分子检测技术的研究%Molecular detection of Erwinia chrysanthemi

    Institute of Scientific and Technical Information of China (English)

    刘鹏; 黄国明; 刘勇; 崔铁军

    2007-01-01

    蝴蝶兰细菌性软腐病对蝴蝶兰的生长危害严重,Erwinia chrysanthemi(菊欧文氏菌)、Erwinia carotovora subsp.carotovora(胡萝卜软腐欧文氏菌胡萝卜软腐亚种)是引起蝴蝶兰软腐病的主要病原细菌,其中E. chrysanthemi被列入我国三类检疫性有害生物.本文对菊欧文氏菌分子检测技术进行了研究,设计出针对该病原细菌的特异性引物,应用实时荧光PCR方法检测样品中存在的菊欧文氏菌,检测灵敏度达到102 cfu/mL.

  17. 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.

  18. Pectin content and composition from different food waste streams.

    Science.gov (United States)

    Müller-Maatsch, Judith; Bencivenni, Mariangela; Caligiani, Augusta; Tedeschi, Tullia; Bruggeman, Geert; Bosch, Montse; Petrusan, Janos; Van Droogenbroeck, Bart; Elst, Kathy; Sforza, Stefano

    2016-06-15

    In the present paper, 26 food waste streams were selected according to their exploitation potential and investigated in terms of pectin content. The isolated pectin, subdivided into calcium bound and alkaline extractable pectin, was fully characterized in terms of uronic acid and other sugar composition, methylation and acetylation degree. It was shown that many waste streams can be a valuable source of pectin, but also that pectin structures present a huge structural diversity, resulting in a broad range of pectin structures. These can have different physicochemical and biological properties, which are useful in a wide range of applications. Even if the data could not cover all the possible batch by batch and country variabilities, to date this represents the most complete pectin characterization from food waste streams ever reported in the literature with a homogeneous methodology.

  19. Nutritional implications of pectins in chicks in relation to esterification and origin of pectins.

    Science.gov (United States)

    Langhout, D J; Schutte, J B

    1996-10-01

    An experiment was conducted to examine the effect of feeding high-methylated (HM) and low-methylated (LM) pectin on performance and physiological characteristics in broiler chicks. Two levels each (1.5 and 3%) of HM citrus pectin (HMC), LM citrus pectin (LMC), or HM sugar beet pectin (HMS) were added to a semi-purified basal diet. The experiment was conducted in battery brooders, and chicks received the diets as pellets from 6 to 27 d of age. The inclusion of LMC or HMS in the diet had little or no effect on the performance of chicks; however, when HMC was added to the diet growth and feed utilization were reduced significantly (P Waterholding capacity of the diets and the excreta were increased significantly by including one (P 0.05) on the concentration of VFA. In contrast, inclusion of HMS in the diet significantly increased the concentration of VFA in the cecal content (P < 0.05) dose-dependently. Based on the results of the present study, it can be concluded that the effect of dietary pectin on chick performance is dependent on the degree of carboxyl groups that is esterified, the origin of the pectin product, and the amount added to the diet.

  20. Natural Pectin Polysaccharides as Edible Coatings

    Directory of Open Access Journals (Sweden)

    Arantzazu Valdés

    2015-11-01

    Full Text Available The most fashionable trends in food packaging research are targeted towards improvements in food quality and safety by increasing the use of environmentally-friendly materials, ideally those able to be obtained from bio-based resources and presenting biodegradable characteristics. Edible films represent a key area of development in new multifunctional materials by their character and properties to effectively protect food with no waste production. The use of edible films should be considered as a clean and elegant solution to problems related with waste disposal in packaging materials. In particular, pectin has been reported as one of the main raw materials to obtain edible films by its natural abundance, low cost and renewable character. The latest innovations in food packaging by the use of pectin-based edible films are reviewed in this paper, with special focus on the use of pectin as base material for edible coatings. The structure, properties related to the intended use in food packaging and main applications of pectins are herein reported.

  1. 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

    The gelling properties of pectin are known to be closely related to the degree of methylation (DM) and the distribution of the ester groups. In order to investigate this dependency, a natural citrus pectin (DM=64%) has been methylated to pectins with higher DM’s or saponified to achieve pectins...... than with unmodified pectin. The new reduced pectins exhibit high gelling properties. Keywords: Pectin; Methylation; Deesterification; Reduction; DM and DR by 1H-NMR spectroscopy; Reduced Pectin; Pectinases; Gelling properties....

  2. Pectin-based oral drug delivery to the colon.

    Science.gov (United States)

    Sande, Sverre Arne

    2005-05-01

    This review presents an overview of studies concerning oral formulations intended for site-specific drug delivery to the colon with pectin as the main excipient. The biological aspects covered include gastrointestinal transit and the enzymatic degradation of pectin. Scintigraphic methods demonstrating the functionality of pectin formulations are discussed. The main focus is on the various formulations reported, including matrix tablets, multiparticulate formulations as pellets and hydrogel beads, and pectin-based coatings. Also included is an evaluation of common excipients employed to improve colon specificity by crosslinking or increasing the hydrophobicity. Finally, properties of the pectin molecules that are important for successful formulations are examined. The conclusion is that the studies found in the literature provide an excellent platform for the development of pectin-based colon delivery systems.

  3. 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.

  4. To the question of production of pectin from beet pulp

    Directory of Open Access Journals (Sweden)

    Yu. I. Zelepukin

    2016-01-01

    Full Text Available Since at present their needs for pectin confectionery and pharmaceutical enterprises in Russia is satisfied only in part, because of the import of this product, the problem is currently the domestic production of pectin is very urgent. Sugar production is one of the branches materialconsuming industrial production, requiring a significant amount of raw materials per unit of output. A positive feature of beet raw material is that protopectin content of up to 98% of the total amount of pectin, which makes the extraction process parameters of the desired product. Dried beet pulp coming from the warehouse, is ground for the intensification of the processes of extraction of pectin; further pulp is hydrolyzed; the resulting mixture is sent to a filter press for coarse and fine purification of the extract. Hydrolyse pulp after neutralization fed to cattle feed. The extract was fed to a thin filter cleaning. After purification, the extract fed to precipitate pectin. Then it is crushed, cleaned and dried. The dried pectin packaged and sent to storage. The proposed technological scheme will allow to receive beet pectin, satisfying the requirements of the pectin substances of food and medical supplies. Studies have been conducted to obtain pectin from dried pulp. The resulting pectin organoleptic had a gray tint, which have a negative effect on the quality of the product. The pulp used as a raw material, which is dried by means of flue gases. For comparison was obtained pectin from dried beet pulp, as a coolant which use steam. Pectin is derived from such a pulp had higher quality indicators.

  5. 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.

  6. Dynamic modelling of pectin extraction describing yield and functional characteristics

    DEFF Research Database (Denmark)

    Andersen, Nina Marianne; Cognet, T.; Santacoloma, P. A.

    2017-01-01

    A dynamic model of pectin extraction is proposed that describes pectin yield, degree of esterification and intrinsic viscosity. The dynamic model is one dimensional in the peel geometry and includes mass transport of pectin by diffusion and reaction kinetics of hydrolysis, degradation and de......-esterification. The model takes into account the effects of the process conditions such as temperature and acid concentration on extraction kinetics. It is shown that the model describes pectin bulk solution concentration, degree of esterification and intrinsic viscosity in pilot scale extractions from lime peel...

  7. Macromolecular components of tomato fruit pectin.

    Science.gov (United States)

    Fishman, M L; Gross, K C; Gillespie, D T; Sondey, S M

    1989-10-01

    Chelate and alkaline-soluble pectin extracted from cell walls of pericarp tissue from mature green, turning, and red ripe (Lycopersicon esculentum Mill.) fruit (cv. Rutgers), were studied by high-performance size-exclusion chromatography. Computer-aided curve fitting of the chromatograms to a series of Gaussian-shaped components revealed that pectin from all fractions was composed of a linear combination of five macromolecular-sized species. The relative sizes of these macromolecules as obtained from their radii of gyration were 1:2:4:8:16. Dialysis against 0.05 M NaCl induced partial dissociation of the biopolymers. Apparently, the weight fraction of smaller sized species increased at the expense of larger ones. Also, the dissociation produced low-molecular-weight fragments. Behavior in the presence of 0.05 M NaCl led to the conclusion that cell wall pectin acted as if it were an aggregated mosaic, held together at least partially through noncovalent interactions.

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

    Science.gov (United States)

    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.

  9. 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 either as co

  10. Mechanical characterization of calcium pectinate hydrogel for controlled drug delivery

    Directory of Open Access Journals (Sweden)

    Chung Jin Thau

    2003-01-01

    Full Text Available Calcium pectinate beads, a paniculate hydrogel system, is an attractive drug carrier for oral delivery. In this study, a poorly water-soluble model drug indomethacin was incorporated into calcium pectinate beads made of different pectin concentrations, which were produced by an extrusion method. The effect of pectin concentration on bead size, circularity, swelling behavior, and mechanical properties, as well as in vitro drug release profile was investigated. The mechanical properties of calcium pectinate beads were determined by a micromanipulation technique. The drug release profile was measured using a standard British Pharmacopoeia method. It was found that the beads made of higher pectin concentration in general had a less permeable matrix structure and greater mechanical rigidity, although they swelled more after hydration. However, such an effect was not significant when the pectin concentration was increased to above 8%. Micromanipulation measurements showed that there was significant relaxation of the force being imposed on single hydrated beads when they were held, but this phenomenon did not occur on dry beads, which means that the force relaxation was dominated by liquid loss from the beads. The rate of the force relaxation was determined, and has been related to the release rate of the model drug entrapped in the calcium pectinate beads.

  11. Physicochemical properties of pectins from okra (Abelmoschus esculentus (L.) Moench)

    NARCIS (Netherlands)

    Sengkhamparn, N.; Sagis, L.M.C.; Vries, de R.J.; Schols, H.A.; Sajjaanantakul, T.; Voragen, A.G.J.

    2010-01-01

    Okra pectin obtained by hot buffer extraction (HBSS) consists of an unusual pectic rhamnogalacturonan I structure in which acetyl groups and alpha galactose residues are substituted on rhamnose residues within the backbone. The okra Chelating agent Soluble Solids (CHSS) pectin consists of slightly d

  12. Influence of pectin characteristics on complexation with ß-lactoglobulin

    NARCIS (Netherlands)

    Sperber, B.L.H.M.

    2010-01-01

    Pectin and proteins are both common food constituents. The type of pectin that forms complexes with protein is known to be of great influence on the structure and stability of liquid foods. Therefore, the aim of this thesis is to investigate the influence of the overall charge and local charge densi

  13. Gelatin-Pectin Composite Films from Polyion Complex Hydrogels

    Science.gov (United States)

    Composite films from gelatin and low-methoxyl pectin were prepared by either ionic complexation or covalent cross-linking. The ionic interactions between positively charged gelatin and negatively charged pectin produced physically reversible hydrogels. The resultant homogeneous gels had improved mec...

  14. Advances in pectin and pectinase research : 2nd symposium on pectins and pectinases

    NARCIS (Netherlands)

    Voragen, A.G.J.; Schols, H.A.; Visser, R.G.F.

    2003-01-01

    The second international symposium on Pectins and Pectinases was organised by Wageningen University and Research Centre and was held in Rotterdam, May 6-10, 2001. This fruitful meeting was attended by around 130 participants from more than 20 countries, representing almost all of the groups/industri

  15. Pectin and charge modified pectin hydrogel beads as a colon-targeted drug delivery carrier.

    Science.gov (United States)

    Jung, Jiyoung; Arnold, Robert D; Wicker, Louise

    2013-04-01

    The physical and chemical properties of commercial low methoxyl citrus pectins, CP 28 and CP 55, and a pectinmethylesterase (PME) charge modified citrus pectin (MP 38) were compared, and the differences in ability to encapsulate indomethacin in hydrogel beads was determined at 0.5 or 1.0% (w/v) indomethacin ratio, and 100, 200 or 300 mM CaCl(2) solution. In order to investigate the drug release characteristics, indomethacin loaded dried hydrogel beads were immersed in simulated gastric fluids (pH 1.2) for 2h, followed by immersing in simulated intestinal fluids (pH 7.4) for 3h. Pectin type was highly significant (ppectin hydrogel bead was less than 15% in simulated gastro-intestinal fluids. MP 38 beads showed significantly higher entrapment efficiency and lower release rate than beads formed from CP 28 or CP 55. MP 38 hydrogel formulated with 300 mM CaCl(2) and 0.5% indomethacin ratio showed the highest entrapment efficiency. These studies suggest that charge modification of pectin improves encapsulation efficiency of drugs for colon targeted drug delivery system through oral administration.

  16. 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...

  17. 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.

  18. Roles of pectin in biomass yield and processing for biofuels

    Directory of Open Access Journals (Sweden)

    Chaowen eXiao

    2013-03-01

    Full Text Available Pectin is a component of the cell walls of plants that is composed of acidic sugar-containing backbones with neutral sugar-containing side chains. It functions in cell adhesion and wall hydration, and pectin crosslinking influences wall porosity and plant morphogenesis. Despite its low abundance in the secondary cell walls that make up the majority of lignocellulosic biomass, recent results have indicated that pectin influences secondary wall formation in addition to its roles in primary wall biosynthesis and modification. This mini-review will examine these and other recent results in the context of biomass yield and digestibility and discuss how these traits might be enhanced by the genetic and molecular modification of pectin. The utility of pectin as a high-value, renewable biomass co-product will also be highlighted.

  19. A protein phosphatase methylesterase (PME-1) is one of several novel proteins stably associating with two inactive mutants of protein phosphatase 2A.

    Science.gov (United States)

    Ogris, E; Du, X; Nelson, K C; Mak, E K; Yu, X X; Lane, W S; Pallas, D C

    1999-05-14

    Carboxymethylation of proteins is a highly conserved means of regulation in eukaryotic cells. The protein phosphatase 2A (PP2A) catalytic (C) subunit is reversibly methylated at its carboxyl terminus by specific methyltransferase and methylesterase enzymes which have been purified, but not cloned. Carboxymethylation affects PP2A activity and varies during the cell cycle. Here, we report that substitution of glutamine for either of two putative active site histidines in the PP2A C subunit results in inactivation of PP2A and formation of stable complexes between PP2A and several cellular proteins. One of these cellular proteins, herein named protein phosphatase methylesterase-1 (PME-1), was purified and microsequenced, and its cDNA was cloned. PME-1 is conserved from yeast to human and contains a motif found in lipases having a catalytic triad-activated serine as their active site nucleophile. Bacterially expressed PME-1 demethylated PP2A C subunit in vitro, and okadaic acid, a known inhibitor of the PP2A methylesterase, inhibited this reaction. To our knowledge, PME-1 represents the first mammalian protein methylesterase to be cloned. Several lines of evidence indicate that, although there appears to be a role for C subunit carboxyl-terminal amino acids in PME-1 binding, amino acids other than those at the extreme carboxyl terminus of the C subunit also play an important role in PME-1 binding to a catalytically inactive mutant.

  20. Protein Phosphatase Methyl-Esterase PME-1 Protects Protein Phosphatase 2A from Ubiquitin/Proteasome Degradation.

    Science.gov (United States)

    Yabe, Ryotaro; Miura, Akane; Usui, Tatsuya; Mudrak, Ingrid; Ogris, Egon; Ohama, Takashi; Sato, Koichi

    2015-01-01

    Protein phosphatase 2A (PP2A) is a conserved essential enzyme that is implicated as a tumor suppressor based on its central role in phosphorylation-dependent signaling pathways. Protein phosphatase methyl esterase (PME-1) catalyzes specifically the demethylation of the C-terminal Leu309 residue of PP2A catalytic subunit (PP2Ac). It has been shown that PME-1 affects the activity of PP2A by demethylating PP2Ac, but also by directly binding to the phosphatase active site, suggesting loss of PME-1 in cells would enhance PP2A activity. However, here we show that PME-1 knockout mouse embryonic fibroblasts (MEFs) exhibit lower PP2A activity than wild type MEFs. Loss of PME-1 enhanced poly-ubiquitination of PP2Ac and shortened the half-life of PP2Ac protein resulting in reduced PP2Ac levels. Chemical inhibition of PME-1 and rescue experiments with wild type and mutated PME-1 revealed methyl-esterase activity was necessary to maintain PP2Ac protein levels. Our data demonstrate that PME-1 methyl-esterase activity protects PP2Ac from ubiquitin/proteasome degradation.

  1. 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.

  2. Microstructure and Kinetic Rheological Behavior of Amidated and Nonamidated LM Pectin Gels

    NARCIS (Netherlands)

    Lofgren, C.; Guillotin, S.E.; Hermansson, A.M.

    2006-01-01

    The microstructure, kinetics of gelation, and rheological properties have been investigated for gels of nonamidated pectin (C30), amidated pectin (G), and saponified pectin (sG) at different pH values, both with and without sucrose. The low-methoxyl (LM) pectin gels were characterized in the presenc

  3. 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.

  4. Engineering of acidic O/W emulsions with pectin.

    Science.gov (United States)

    Alba, K; Sagis, L M C; Kontogiorgos, V

    2016-09-01

    Pectins with distinct molecular design were isolated by aqueous extraction at pH 2.0 or 6.0 and were examined in terms of their formation and stabilisation capacity of model n-alkane-in-water emulsions at acidic pH (pH 2.0). The properties and stability of the resulting emulsions were examined by means of droplet size distribution analysis, Lifshitz-Slyozov-Wagner modelling, bulk rheology, interfacial composition analysis, large-amplitude oscillatory surface dilatational rheology, electrokinetic analysis and fluorescence microscopy. Both pectin preparations were able to emulsify alkanes in water but exhibited distinct ageing characteristics. Emulsions prepared using pectin isolated at pH 6.0 were remarkably stable with respect to droplet growth after thirty days of ageing, while those prepared with pectin isolated at pH 2.0 destabilised rapidly. Examination of chemical composition of interfacial layers indicated multi-layered adsorption of pectins at the oil-water interface. The higher long-term stability of emulsions prepared with pectin isolated at high pH is attributed to mechanically stronger interfaces, the highly branched nature and the low hydrodynamic volume of the chains that result in effective steric stabilisation whereas acetyl and methyl contents do not contribute to the long-term stability. The present work shows that it is possible by tailoring the fine structure of pectin to engineer emulsions that operate in acidic environments.

  5. Process-Structure-Function Relations of Pectin in Food.

    Science.gov (United States)

    Christiaens, Stefanie; Van Buggenhout, Sandy; Houben, Ken; Jamsazzadeh Kermani, Zahra; Moelants, Katlijn R N; Ngouémazong, Eugénie D; Van Loey, Ann; Hendrickx, Marc E G

    2016-01-01

    Pectin, a complex polysaccharide rich in galacturonic acid, has been identified as a critical structural component of plant cell walls. The functionality of this intricate macromolecule in fruit- and vegetable-based-derived products and ingredients is strongly determined by the nanostructure of its most abundant polymer, homogalacturonan. During food processing, pectic homogalacturonan is susceptible to various enzymatic as well as nonenzymatic conversion reactions modifying its structural and, hence, its functional properties. Consequently, a profound understanding of the various process-structure-function relations of pectin aids food scientists to tailor the functional properties of plant-based derived products and ingredients. This review describes the current knowledge on process-structure-function relations of pectin in foods with special focus on pectin's functionality with regard to textural attributes of solid plant-based foods and rheological properties of particulated fruit- and vegetable-derived products. In this context, both pectin research performed via traditional, ex situ physicochemical analyses of fractionated walls and isolated polymers and pectin investigation through in situ pectin localization are considered.

  6. Pectin from Abelmoschus esculentus: optimization of extraction and rheological properties.

    Science.gov (United States)

    Chen, Yi; Zhang, Jian-Guo; Sun, Han-Ju; Wei, Zhao-Jun

    2014-09-01

    Response surface methodology (RSM) was applied to optimize the parameters of pectin extraction from okra pods. The extracted okra pectin was then investigated by steady-shear and oscillatory rheological measurements. Statistical analysis showed that the linear term of the liquid-solid ratio, the quadratic term of the pH, and the linear term of the extraction time showed highly significant effects on pectin yield. The optimal extraction conditions that maximized the pectin yield within the experimental range of the variables researched were a pH of 3.9, an extraction time of 64 min, an extraction temperature of 60°C, and a liquid-solid ratio of 42:1. Under these conditions, the pectin yield was predicted to be 2.71%. At a liquid-solid ratio less than 2.5% w/w in aqueous solution, the pectin extracted from okra presented non-Newtonian shear-thinning behavior and could be well described by the Cross model. The okra pectin showed predominantly viscous responses (G'

  7. Ultrasound assisted extraction and characterization of pectin from tomato waste.

    Science.gov (United States)

    Grassino, Antonela Ninčević; Brnčić, Mladen; Vikić-Topić, Dražen; Roca, Sunčica; Dent, Maja; Brnčić, Suzana Rimac

    2016-05-01

    Pectin was extracted from tomato waste using two different extraction methods to assess its potential utilization as an alternative source of commercial pectin production. Tomato waste was treated with ammonium oxalate/oxalic acid by conventional extraction (CE), under reflux and ultrasound assisted extraction (UAE) at 37 kHz and temperatures of 60 °C and 80 °C. The pectin obtained from these methods was analysed and compared in terms of yield, chemical properties and structure. Among examined methods, CE at 60 °C resulted with the highest yield, but UAE during 15 min of sonication produced the pectin of better quality (anhydrouronic acid, methoxy and calcium pectate contents and degree of esterification). NMR and FTIR spectroscopy of isolated pectins revealed predominantly esterified structure, irrespective of extraction conditions. The comparison of the pectin yields obtained after extraction at 80 °C, indicate that similar values were found at times of 24h and 15 min for CE and UAE, respectively. According to obtained results it can be concluded that main advantage of UAE is considerable shortening of extraction procedure with strong emphasis on environmental friendly processing approach. Therefore, these results suggested that UAE could be used as an efficient technique for the extraction of pectin from tomato waste and by-products.

  8. Structure of a Rhamnogalacturonan Fragment from Apple Pectin: Implications for Pectin Architecture

    Directory of Open Access Journals (Sweden)

    Xiangmei Wu

    2014-01-01

    Full Text Available A commercial apple pectin was sequentially digested with the cloned enzymes endopolygalacturonase, galactanase, arabinofuranosidase, xylogalacturonase, and rhamnogalacturonan hydrolase. The rhamnogalacturonan hydrolase-generated oligosaccharides were separated by ultrafiltration, anion exchange, and size-exclusion chromatography. Fractions from the ion exchange chromatography were pooled, lyophilized, and screened by MALDI-TOF MS. An oligosaccharide (RGP14P3 was identified and its structure, α-D-GalpA-(1→2-α-L-Rhap-(1→4-α-D-GalpA-(1→2-α-L-Rhap-(1→4-α-D-GalpA, determined by 1D and 2D NMR spectrometry. This oligosaccharide probably represents a direct connection between homogalacturonan and rhamnogalacturonan in pectin. Alternatively, it could indicate that the nonreducing end of rhamnogalacturonan starts with a galacturonic acid residue.

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

    Science.gov (United States)

    Pedrolli, Danielle Biscaro; Carmona, Eleonora Cano

    2014-01-01

    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 Pb(2+) and was not significantly affected by Hg(2+). Like other pectin lyases, PLIII is stimulated by but is not dependent on Ca(2+). 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Influence of the overall charge and local charge density of pectin on the complex formation between pectin and beta-lactoglobulin

    NARCIS (Netherlands)

    Sperber, Bram L. H. M.; Schols, Henk A.; Stuart, Martien A. Cohen; Norde, Willem; Voragen, Alphons G. J.

    2009-01-01

    The complex formation between beta-lactoglobulin (beta-lg) and pectin is studied using pectins with different physicochemical characteristics. Pectin allows for the control of both the overall charge by degree of methyl-esterification as well as local charge density by the degree of blockiness. Vary

  12. DEVELOPING THE METHOD FOR PRODUCING FUNCTIONAL TONIC DRINKS CONTAINING PECTIN

    Directory of Open Access Journals (Sweden)

    Galut N. V.

    2013-12-01

    Full Text Available Main technologic characteristics were developed for the production of functional tonic drinks containing pectin. Their component composition was justified. Their physical, chemical and organoleptic properties were determined

  13. Novel pectin-based carriers for colonic drug delivery.

    Science.gov (United States)

    Zhang, Wujie; Mahuta, Kirsten Mary; Mikulski, Brandon Anthony; Harvestine, Jenna Nicole; Crouse, James Zachary; Lee, Jung Chull; Kaltchev, Matey Georgiev; Tritt, Charles Samuel

    2016-01-01

    Pectin-based hydrogel carriers have been studied and shown to have promising applications for drug delivery to the lower GI tract, especially to the colonic region. However, making sure these hydrogel carriers can pass through the upper GI tract and reach the targeted regions, after oral administration, still remains a challenge to overcome. A solution to this problem is to promote stronger cross-linking interactions within the pectin-based hydrogel network. The combined usage of a divalent cation (Ca(2+)) and the cationic biopolymer oligochitosan has shown to improve the stability of pectin-based hydrogel systems - suggesting that these two cross-linkers may be used to eventually help improve pectin-based hydrogel systems for colonic drug delivery methods.

  14. 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......; 6 mol % arabinose). Wild-type (modified hairy region from potato pectin (MHRP)_WT) fragment contained default amounts (58 mol % galactose; 13 mol % arabinose) of both sugars. Focal adhesions (FAs) indicating cellular attachment were quantified. Reverse transcriptase polymerase chain reaction (RT...... any of the pectin samples, of which the MHRP_WT seemed to function best. FA length was greater on MHRPTR_GAL than on other pectin samples, otherwise the mutants did not significantly deviate. RT-PCR results indicate that differences between the samples at the gene expression level might be even...

  15. 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 continuous input ofuncontrolled disturbances to the process. Consequently, the processconditions should be constantly adjusted in order to obtain a highpectin yield and good product quality. The pectin quality can becharacterized by the degree of esterification (%DE) [2].Measurements of %DE can only...... be carried out after precipitation,which occurs several hours from the start of extraction. As aconsequence, some batches are processed under non-optimalconditions reducing pectin yield and quality....

  16. 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%

  17. Various-sourced pectin and polyethylene oxide electrospun fibers.

    Science.gov (United States)

    Rockwell, Pamela L; Kiechel, Marjorie A; Atchison, Jennifer S; Toth, Laura J; Schauer, Caroline L

    2014-07-17

    Pectin, a naturally occurring and biorenewable polysaccharide, is derived from plant cell wall tissue and used in applications ranging from food processing to biomedical engineering. Due to extraction methods and source variation, there is currently no consensus in literature as to the exact structure of pectin. Here, we have studied key material properties of electrospun pectin blends with polyethylene oxide (PEO) (1:1, v/v) in order to demonstrate the fabrication of a fibrous and less toxic material system, as well as to understand the effects of source variability on the resulting fibrous mats. The bulk pectin degree of esterification (DE) estimated using FTIR (bulk apple pomace (AP)=28%, bulk citrus peel (CP)=86% and bulk sugar beet pulp (SBP)=91%) was shown to inversely correlate with electrospun fiber crystallinity determined using XRD (PEO-AP=37%, PEO-CP=28% and PEO-SBP=23%). This in turn affected the trend observed for the mean fiber diameter (n=50) (PEO-AP=124 ± 26 nm, PEO-CP=493 ± 254 nm and PEO-SBP=581 ± 178 nm) and elastic tensile moduli (1.6 ± 0.2 MPa, 4.37 ± 0.64 MPa and 2.49 ± 1.46 MPa, respectively) of the fibrous mats. Electrospun fibers containing bulk AP had the lowest DE, highest crystallinity, smallest mean fiber diameter, and lowest tensile modulus compared to either the bulk CP or bulk SBP. Bound water in PEO-CP fiber and bulk pectin impurities in PEO-SPB were observed to influence fiber branching and mean diameter distributions, which in turn influenced the fiber tensile properties. These results indicate that pectin, when blended with PEO in water, produces submicron fibrous mats with pectin influencing the blend fiber properties. Moreover, the source of pectin is an important variable in creating electrospun blend fibrous mats with desired material properties.

  18. Preparation and Characterization of Pectin Hydroxamates from Citrus Unshiu Peels.

    Directory of Open Access Journals (Sweden)

    In Young Bae

    2011-09-01

    Full Text Available Pectin was extracted from unshiu orange (Citrus unshiu peels and was subjected to chemical modification using hydroxamic acid. The structural and physical properties of the resulting derivatives were investigated as a function of hydroxamic acid content (4.68-9.58%. The extracted unshiu orange pectin showed 66.8% degree of esterification, 787.5 mg/g galacturonic acid, and 92 mg/g neutral sugars, which were composed of arabinose (53%, galactose (35%, glucose (5%, rhamnose (5%, and fructose (2%. Compared to the nativepectin, the FT-IR spectra of the hydroxamic acid derivatives showed two new absorption bands at 1,646 cm-1 (C=O and 1,568 cm-1 (N-H. Specifically, the pectin derivatives with more hydroxamic acids were shown to have enhanced water solubility, upto two-fold higher than that of the native pectin. Thus, the introduction of hydroxamic acid into the pectin structure appears to be a useful tool for improving the solubility of pectin.

  19. Faba bean hulls as a potential source of pectin.

    Science.gov (United States)

    Korish, Mohamed

    2015-09-01

    This study aimed for the first time to assess the potential use of faba bean hulls as a source of pectin. The study involved extracting pectin under various conditions of pH, temperature and extraction time and determining how these conditions affected pectin yield and its characteristics. The maximum yield of extracted pectin did not coincide with the highest degree of esterification since the maximum yield (15.75 %) was recorded at pH 1.5 and at a temperature of 85 °C for an 80-min extraction period and solid to liquid (1: 25) ratio, while the highest degree of esterification (54.62 %) occurred at pH 2.5 and at temperature of 90 °C for a 60-min extraction period. The composition of the pectin varied according to the extraction conditions: the neutral sugars galactose, arabinose and rhamnose increased under milder extraction conditions while glucose, mannose and xylose sugars predominated under harsher extraction conditions. The results indicated that faba bean hulls contains adequate amount of pectin, suitable for commercial utilization.

  20. 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.

  1. 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.

  2. Pineapple and banana pectins comprise fewer homogalacturonan building blocks with a smaller degree of polymerization as compared with yellow passion fruit and lemon pectins: implication for gelling properties.

    Science.gov (United States)

    Yapo, Beda M

    2009-04-13

    Pectins are viewed as multiblock cobiopolymers of different pectic polysaccharides, notably, homogalacturonan (HG) and rhamnogalacturonan I (RG I). Furthermore, on the basis of HGs isolated from different (pectins from) dicot cell walls, HG is supposed to have an average degree of polymerization (DP) of approximately 100 irrespective of the plant source. To validate or invalidate these suppositions, pectins from both monocot (pineapple and banana) and dicot (yellow passion fruit and lemon) cell walls were examined. The results show that all the extracted pectins comprise HGs as well as type I and II arabinogalactan side chain-containing RGs I, but of significantly (p properties of pectin.

  3. THE USE OF HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY AS SCREENING TECHNIQUE FOR PECTIN AND PECTIN SUBSTANCES OF DIETARY FIBERS

    Directory of Open Access Journals (Sweden)

    G.N. Ignatyeva

    2015-02-01

    Full Text Available The peak of the unspecified compound of quantitative analysis of organic acids in biological materials by using high-performance liquid chromatography was identified. This peak corresponded to polygalacturonic acid. A High-performance liquid chromatographic method was developed to identify and quantify of water soluble pectin fraction and insoluble pectin fraction, galacturonic acid and polygalacturonic acid. The method based on the extraction of free water soluble fraction with phosphate buffer (pH 4.8 or with 0.01 N phosphoric acid and on the acid hydrolysis of insoluble pectin fraction in presence 0.1 N HNO3. The pectin fractions were separated and determined on a C610H column using elution with 0.01 N phosphoric acids and ultraviolet detection at 210 nm. Galacturonic acid and polygalacturonic acid were used as internal standard. The calibration curves were presented for each of the standards. The determinations were performed in the linear range of 0.04÷0.17% w/v for both pectin fractions. Proposed procedure can considered as a rapid method for quantitative pectin determination in the food, food nutrition’s food, and pharmaceutical agents.

  4. Pectin enhances rice (Oryza sativa) root phosphorus remobilization.

    Science.gov (United States)

    Zhu, Xiao Fang; Wang, Zhi Wei; Wan, Jiang Xue; Sun, Ying; Wu, Yun Rong; Li, Gui Xin; Shen, Ren Fang; Zheng, Shao Jian

    2015-02-01

    Plants growing in phosphorus (P)-deficient conditions can either increase their exploration of the environment (hence increasing P uptake) or can solubilize and reutilize P from established tissue sources. However, it is currently unclear if P stored in root cell wall can be reutilized. The present study shows that culture of the rice cultivars 'Nipponbare' (Nip) and 'Kasalath' (Kas) in P-deficient conditions results in progressive reductions in root soluble inorganic phosphate (Pi). However, Nip consistently maintains a higher level of soluble Pi and lower relative cell wall P content than does Kas, indicating that more cell wall P is released in Nip than in Kas. P-deficient Nip has a greater pectin and hemicellulose 1 (HC1) content than does P-deficient Kas, consistent with the significant positive relationship between pectin and root-soluble Pi levels amongst multiple rice cultivars. These observations suggest that increased soluble Pi might result from increased pectin content during P starvation. In vitro experiments showed that pectin releases Pi from insoluble FePO4. Furthermore, an Arabidopsis thaliana mutant with reduced pectin levels (qua1-2), has less root soluble Pi and is more sensitive to P deficiency than the wild type (WT) Col-0, whereas NaCl-treated WT plants exhibit both an increased root pectin content and an elevated soluble Pi content during P-starvation. These observations indicate that pectin can facilitate the remobilization of P deposited in the cell wall. This is a previously unknown mechanism for the reutilization of P in P-starved plants.

  5. Some of the out genes involved in the secretion of pectate lyases in Erwinia chrysanthemi are regulated by kdgR.

    Science.gov (United States)

    Condemine, G; Dorel, C; Hugouvieux-Cotte-Pattat, N; Robert-Baudouy, J

    1992-11-01

    The out genes of Erwinia chrysanthemi are required for the translocation across the outer membrane of pectate lyases and cellulases. We present the characterization and the nucleotide sequence of five genes of the out cluster. The products of outS, B, C, D and E have significant homology with the PulS, B, C, D and E proteins necessary to the secretion of pullulanase in Klebsiella pneumoniae. An open reading frame, outT, located between outB and outC has no homology with the pul cluster but is involved in secretion. outC, outD and outE form an operon while outS, outB and outT constitute independent transcription units. outT and the outCDE operon are regulated by kdgR, the negative regulatory gene controlling pectinase production. outB and outS seem to be expressed constitutively.

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

    Science.gov (United States)

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

    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.

  7. 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.

  8. How to let go: pectin and plant cell adhesion

    Science.gov (United States)

    Daher, Firas Bou; Braybrook, Siobhan A.

    2015-01-01

    Plant cells do not, in general, migrate. They maintain a fixed position relative to their neighbors, intimately linked through growth and differentiation. The mediator of this connection, the pectin-rich middle lamella, is deposited during cell division and maintained throughout the cell’s life to protect tissue integrity. The maintenance of adhesion requires cell wall modification and is dependent on the actin cytoskeleton. There are developmental processes that require cell separation, such as organ abscission, dehiscence, and ripening. In these instances, the pectin-rich middle lamella must be actively altered to allow cell separation, a process which also requires cell wall modification. In this review, we will focus on the role of pectin and its modification in cell adhesion and separation. Recent insights gained in pectin gel mechanics will be discussed in relation to existing knowledge of pectin chemistry as it relates to cell adhesion. As a whole, we hope to begin defining the physical mechanisms behind a cells’ ability to hang on, and how it lets go. PMID:26236321

  9. How to let go: pectin and plant cell adhesion

    Directory of Open Access Journals (Sweden)

    Firas eBou Daher

    2015-07-01

    Full Text Available Plant cells do not, in general, migrate. They maintain a fixed position relative to their neighbours, intimately linked through growth and differentiation. The mediator of this connection, the pectin-rich middle lamella, is deposited during cell division and maintained throughout the cell’s life to protect tissue integrity. The maintenance of adhesion requires cell wall modification and is dependent on the actin cytoskeleton. There are developmental processes that require cell separation, such as organ abscission, dehiscence, and ripening. In these instances, the pectin-rich middle lamella must be actively altered to allow cell separation, a process which also requires cell wall modification. In this review, we will focus on the role of pectin and its modification in cell adhesion and separation. Recent insights gained in pectin gel mechanics will be discussed in relation to existing knowledge of pectin chemistry as it relates to cell adhesion. As a whole, we hope to begin defining the physical mechanisms behind a cells’ ability to hang on, and how it lets go.

  10. 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.

  11. Amidated pectin based hydrogels: synthesis, characterization and cytocompatibility study.

    Science.gov (United States)

    Mishra, R K; Singhal, J P; Datt, M; Banthia, A K

    2007-01-01

    The design and development of pectin-based hydrogels were attempted through the chemical modification of pectin with diethanolamine (DA). Diethanolamine modified pectin (DAMP) was synthesized by the chemical modification of pectin with varying concentrations of DA (1:1,1:2,1:3 and 1:4) at 5 oC in methanol. The modified product was used for the preparation of the hydrogel with glutaraldehyde (GA) reagent. The prepared hydrogels were characterized by Fourier transform infrared (FTIR) spectroscopy; organic elemental analysis, and X-ray diffraction (XRD), and swelling, hemocompatibility and cytocompatibility studies of the prepared hydrogels were also done. FTIR spectroscopy indicated the presence of primary and secondary amide absorption bands. The XRD pattern of the DAMP hydrogel clearly indicated that there was a considerable increase in crystallinity as compared to parent pectin. The degree of amidation (DA) and molar and mass reaction yields (Ym and Yn) was calculated based on the results of organic elemental analysis. Drug release studies from the hydrogel membranes were also evaluated in a Franz's diffusion cell. The hydrogels demonstrated good water holding properties and were found to be compatible with B-16 melanoma cells and human blood.

  12. Formation and rupture of Ca2+induced pectin biopolymer gels

    Science.gov (United States)

    Basak, Rajib; Bandyopadhyay, Ranjini

    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 performed to study the process of gel rupture. As calcium salt concentration is increased, DLS experiments reveal that the polydispersities 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 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 pectin and salt concentrations are both 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.

  13. Novel hybrid nanostructured materials of magnetite nanoparticles and pectin

    Science.gov (United States)

    Sahu, Saurabh; Dutta, Raj Kumar

    2011-04-01

    A novel hybrid nanostructured material comprising superparamagnetic magnetite nanoparticles (MNPs) and pectin was synthesized by crosslinking with Ca2+ ions to form spherical calcium pectinate nanostructures, referred as MCPs, which were typically found to be 100-150 nm in size in dried condition, confirmed from transmission electron microscopy and scanning electron microscopy. The uniform size distribution was revealed from dynamic light scattering measurement. In aqueous medium the MCPs showed swelling behavior with an average size of 400 nm. A mechanism of formation of spherical MCPs is outlined constituting a MNP-pectin interface encapsulated by calcium pectinate at the periphery, by using an array of characterization techniques like zeta potential, thermogravimetry, Fourier transformed infrared and X-ray photoelectron spectroscopy. The MCPs were stable in simulated gastrointestinal fluid and ensured minimal loss of magnetic material. They exhibited superparamagnetic behavior, confirmed from zero field cooled and field cooled profiles and showed high saturation magnetization (Ms) of 46.21 emu/g at 2.5 T and 300 K. Ms decreased with increasing precursor pectin concentrations, attributed to quenching of magnetic moments by formation of a magnetic dead layer on the MNPs.

  14. Low level hydrogen peroxide generation from a nonwoven fibrous pectin-cellulose blend

    Science.gov (United States)

    Fibrous pectic-cellulose (FPC) (cellulose blended with primary cell wall pectin at 2 percent by weight of pectin) is product made from naturally occurring plant fibers. FPC is a fibrous mixture of polysaccharides with a low percent by weight of pectin-based primary cell wall and lipid components att...

  15. 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.

  16. Action pattern of Valencia orange PME de-esterification of high methoxyl pectin and characterization of modified pectins.

    Science.gov (United States)

    Kim, Yookyung; Teng, Quincy; Wicker, Louise

    2005-12-12

    Valencia pectinmethylesterase (PME) fractions, B-PME, containing 36 and 13 kDa protein bands and U-PME, containing a 36 and 27 kDa protein bands, were used to de-esterify original pectin (O-Pec) from 73% degree of esterification (%DE) to 63% (B-Pec) and 61% DE (U-Pec), respectively. Most O-Pec eluted from ion exchange chromatography at low salt concentration and a smaller component eluted at higher ionic strength. B-Pec and U-Pec eluted as one broad peak at higher ionic strength. PME modification did not change molecular weight: O-pectin (134,000 g/mol), U-Pec (133,850 g/mol), and B-Pec (132,250 g/mol). The NMR signal of GG and GGG increased after modification, whereas the signal of EE and EEE decreased. The negative zeta-potential increased with pH for all pectins. U-PME and B-PME created differently modified pectins that vary in degree and length of multiple attacks and fraction of the pectin population that was modified.

  17. Enzymatic gelation of sugar beet pectin in food products

    DEFF Research Database (Denmark)

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

    2000-01-01

    in standard gels. Protein reduced the hardness, stiffness and chewiness of the gels whereas there were some variation in the effect of protein on the adhesiveness of the gels. Sugar beet pectin in black currant juice formed a gel and a gelation also took place in milk. In luncheon meat a cohesive gel......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...

  18. Ex vivo mucoadhesion of different zinc-pectinate hydrogel beads.

    Science.gov (United States)

    Hagesaether, Ellen; Bye, Ragnar; Sande, S Arne

    2008-01-22

    The objective of this study was to investigate the mucoadhesive properties of pre-swelled hydrogel beads made of six types of pectin from three manufacturers. The types of pectin differed mainly in the degree of methoxylation and degree of amidation. Zinc ions were used as cross-linking agent. The mucoadhesive properties were tested on an inverted fresh porcine small intestine attached to a rotating cylinder. Beads made of pectin with a high degree of methoxylation (70%) showed superior mucoadhesive results compared to the other formulations, which could be correlated to the lower amount of zinc in this formulation, subsequently leading to a lower amount of cross-linking and higher mobility of the polymer chains of these beads. This study therefore also indicated the importance of doing mucoadhesive measurements on relevant formulations, and not basing the understanding solely on investigating polymer solutions. Samples from different manufacturers produced the same results.

  19. Ultrasound-assisted extraction of pectin from sisal waste.

    Science.gov (United States)

    Maran, J Prakash; Priya, B

    2015-01-22

    In this study, an efficient ultrasound-assisted extraction (UAE) of pectin from sisal waste was investigated and optimized. Response surface methodology (RSM) based on a three-level four-factor Box-Behnken response surface design (BBD) was employed to optimize the extraction conditions (ultrasonic power, extraction temperature, extraction time and solid-liquid ratio). Analysis of variance showed that the contribution of a quadratic model was significant for the pectin extraction yield. The experimental yield (29.32%) was obtained under the optimal condition (ultrasonic power of 61 W, temperature of 50°C, time of 26 min and SL ratio of 1:28 g/ml) was well agreement with predicted values. Therefore, ultrasound-assisted extraction could be used as an alternative method to extract pectin from sisal waste with the advantages of lower extraction temperatures, shorter extraction time and reduced energy consumption.

  20. Pectin extraction from pomegranate peels with citric acid.

    Science.gov (United States)

    Pereira, Paulo Henrique F; Oliveira, Túlio Ítalo S; Rosa, Morsyleide F; Cavalcante, Fabio Lima; Moates, Graham K; Wellner, Nikolaus; Waldron, Keith W; Azeredo, Henriette M C

    2016-07-01

    Pectins were extracted from pomegranate peels with citric acid, according to a central composite design with three variables: pH (2-4), temperature (70-90°C), and extraction time (40-150min). Fourier transform infrared (FTIR) spectroscopy was used to follow changes in material composition during the main steps of pectin extraction, and also to determine the degree of methyl esterification and galacturonic acid content of pectins produced under different conditions. Harsh conditions enhanced the extraction yield and the galacturonic acid contents, but decreased the degree of methoxylation. The optimum extraction conditions, defined as those predicted to result in a yield of galacturonic acid higher than 8g/100g while keeping a minimum degree of methoxylation of 54% were: 88°C, 120min, pH 2.5. Close agreement was found between experimental and predicted values at the extraction conditions defined as optimum.

  1. Osteoblastic response to pectin nanocoating on titanium surfaces

    DEFF Research Database (Denmark)

    Gurzawska, Katarzyna; Svava, Rikke; Yihua, Yu

    2014-01-01

    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...... 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...

  2. Novel hybrid nanostructured materials of magnetite nanoparticles and pectin

    Energy Technology Data Exchange (ETDEWEB)

    Sahu, Saurabh [Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247 667 (India); Dutta, Raj Kumar, E-mail: duttafcy@iitr.ernet.i [Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247 667 (India)

    2011-04-15

    A novel hybrid nanostructured material comprising superparamagnetic magnetite nanoparticles (MNPs) and pectin was synthesized by crosslinking with Ca{sup 2+} ions to form spherical calcium pectinate nanostructures, referred as MCPs, which were typically found to be 100-150 nm in size in dried condition, confirmed from transmission electron microscopy and scanning electron microscopy. The uniform size distribution was revealed from dynamic light scattering measurement. In aqueous medium the MCPs showed swelling behavior with an average size of 400 nm. A mechanism of formation of spherical MCPs is outlined constituting a MNP-pectin interface encapsulated by calcium pectinate at the periphery, by using an array of characterization techniques like zeta potential, thermogravimetry, Fourier transformed infrared and X-ray photoelectron spectroscopy. The MCPs were stable in simulated gastrointestinal fluid and ensured minimal loss of magnetic material. They exhibited superparamagnetic behavior, confirmed from zero field cooled and field cooled profiles and showed high saturation magnetization (M{sub s}) of 46.21 emu/g at 2.5 T and 300 K. M{sub s} decreased with increasing precursor pectin concentrations, attributed to quenching of magnetic moments by formation of a magnetic dead layer on the MNPs. - Research highlights: > In the present investigation we have developed a facile route to synthesize a novel, low cost calcium pectinate nanostructure functionalized with SPIONs (magnetite nanoparticles). > Though there are sufficient scientific illustrations on polymer as well as biopolymers coated on SPIONs for various biomedical applications, the one presented here, is novel of its kind as it is considered to offer a new dimension to the magnetic responsive properties of calcium pectinate nanomaterials towards biomedical applications, especially as a potential carrier for magnetically targeted drug delivery to colon specific sites. > The synthesis of these nanostructured

  3. 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...... and chromatographic characterization methods (HPAEC and HPSEC), rheological measurements of elasticity, and biological epitopes detection using carbohydrate microarrays. The end product of this study is expected to contribute to the knowledge of pectin polymeric conformation and structure-function properties as well...

  4. Pectin impacts cellulose fibre architecture and hydrogel mechanics in the absence of calcium.

    Science.gov (United States)

    Lopez-Sanchez, Patricia; Martinez-Sanz, Marta; Bonilla, Mauricio R; Wang, Dongjie; Walsh, Cherie T; Gilbert, Elliot P; Stokes, Jason R; Gidley, Michael J

    2016-11-20

    Pectin is a major polysaccharide in many plant cell walls and recent advances indicate that its role in wall mechanics is more important than previously thought. In this work cellulose hydrogels were synthesised in pectin solutions, as a biomimetic tool to investigate the influence of pectin on cellulose assembly and hydrogel mechanical properties. Most of the pectin (60-80%) did not interact at the molecular level with cellulose, as judged by small angle scattering techniques (SAXS and SANS). Despite the lack of strong interactions with cellulose, this pectin fraction impacted the mechanical properties of the hydrogels through poroelastic effects. The other 20-40% of pectin (containing neutral sugar sidechains) was able to interact intimately with cellulose microfibrils at the point of assembly. These results support the need to revise the role of pectin in cell wall architecture and mechanics, and; furthermore they assist the design of cellulose-based products through controlling the viscoelasticity of the fluid phase.

  5. Pectin/zein microspheres as a sustained drug delivery system

    Science.gov (United States)

    A series of microspheres were prepared from pectins and corn proteins from various sources in the presence of the divalent ions calcium or zinc. The results showed that the yield of microsphere and the efficiency of drug incorporation were dependent on the type and ratio of biopolymers, the size of ...

  6. 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 h

  7. Pectin, a versatile polysaccharide present in plant cell walls

    NARCIS (Netherlands)

    Voragen, A.G.J.; Coenen, G.J.; Verhoef, R.P.; Schols, H.A.

    2009-01-01

    Pectin or pectic substances are collective names for a group of closely associated polysaccharides present in plant cell walls where they contribute to complex physiological processes like cell growth and cell differentiation and so determine the integrity and rigidity of plant tissue. They also pla

  8. Encapsulation systems based on ovalbumin fibrils and high methoxyl pectin

    NARCIS (Netherlands)

    Humblet-Hua, K.N.P.; Scheltens, G.; Linden, van der E.; Sagis, L.M.C.

    2011-01-01

    In this study we produced microcapsules using layer-by-layer adsorption of food-grade polyelectrolytes. The shell was built with alternating layers of ovalbumin fibrils and high methoxyl pectin. By varying the number of layers, the release of active ingredients can be controlled - increasing the num

  9. Characterization and degradation of pectin derived from Budimka apple

    Directory of Open Access Journals (Sweden)

    MILOS V. NIKOLIC

    2008-02-01

    Full Text Available The characterization of apple pectin and its oligogalacturonic fractions derived from the autochthones apple variety Budimka, characteristic for central Serbia, is described in this paper. After extraction, the apple pectin was subjected to controlled enzymatic hydrolysis by polygalacturonase (PG and pectin lyase (PL from Aspergillus niger and then fractionated by ion-exchange column chromatography on Dowex 1X-8 (200–400 mesh. Saturated oligogalacturonic acids, obtained by controlled hydrolysis with PG, were efficiently separated by elution with a gradient of Na acetate buffer (pH 6.0, while unsaturated oligogalacturonic acids, obtained by controlled hydrolysis with PL, were separated on the same resin, using a gradient of Na formate buffer (pH 4.7 as the eluent. The yields of the fractions with the particular degree of polymerization (DP were also determined. The total content of neutral saccharides in the original Budimka apple pectin was detected by HPLC analysis of the 4-nitrobenzoyl derivatives of the sugar, and amounted to 5.31 %. Among the neutral saccharides, contents of galactose, glucose, rhamnose, arabinose, xylose and mannose were detected.

  10. Pectin as an Extraordinary Natural Kinetic Hydrate Inhibitor

    Science.gov (United States)

    Xu, Shurui; Fan, Shuanshi; Fang, Songtian; Lang, Xuemei; Wang, Yanhong; Chen, Jun

    2016-03-01

    Pectin as a novel natural kinetic hydrate inhibitor, expected to be eco-friendly and sufficiently biodegradable, was studied in this paper. The novel crystal growth inhibition (CGI) and standard induction time methods were used to evaluate its effect as hydrate inhibitor. It could successfully inhibit methane hydrate formation at subcooling temperature up to 12.5 °C and dramatically slowed the hydrate crystal growth. The dosage of pectin decreased by 66% and effective time extended 10 times than typical kinetic inhibitor. Besides, its maximum growth rate was no more than 2.0%/h, which was far less than 5.5%/h of growth rate for PVCap at the same dosage. The most prominent feature was that it totally inhibited methane hydrate crystal rapid growth when hydrate crystalline occurred. Moreover, in terms of typical natural inhibitors, the inhibition activity of pectin increased 10.0-fold in induction time and 2.5-fold in subcooling temperature. The extraordinary inhibition activity is closely related to its hydrogen bonding interaction with water molecules and the hydrophilic structure. Finally, the biodegradability and economical efficiency of pectin were also taken into consideration. The results showed the biodegradability improved 75.0% and the cost reduced by more than 73.3% compared to typical commercial kinetic inhibitors.

  11. Optimization of microwave assisted extraction of pectin from orange peel.

    Science.gov (United States)

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

    2013-09-12

    In this study, microwave-assisted extraction was applied for pectin extraction from the dried orange peel and Box-Behnken response surface design was used to study and optimize the effects of processing variables (microwave power, irradiation time, pH and solid-liquid ratio) on the yield of pectin. The amount of pectin extracted increased with increasing microwave power, while it reduces as the time, pH and solid-liquid ratio increased. From the results, second order polynomial model was developed and it adequately explained the data variation and significantly represented the actual relationship between independent variables and the response. An optimization study using Derringer's desired function methodology was performed and optimal conditions based on both individual and combinations of all independent variables (microwave power of 422W, irradiation time of 169 s, pH of 1.4 and solid-liquid ratio of 1:16.9 g/ml) were determined with maximum pectin yield of 19.24%, which was confirmed through validation experiments.

  12. Facile and green synthesis of silver nanoparticles using oxidized pectin

    Energy Technology Data Exchange (ETDEWEB)

    Tummalapalli, Mythili; Deopura, B.L. [Bioengineering Lab, Department of Textile Technology, Indian Institute of Technology, Hauz Khas, New Delhi 110016 (India); Alam, M.S. [Department of Chemistry, Jamia Hamdard, New Delhi 110062 (India); Gupta, Bhuvanesh, E-mail: bgupta@textile.iitd.ernet.in [Bioengineering Lab, Department of Textile Technology, Indian Institute of Technology, Hauz Khas, New Delhi 110016 (India)

    2015-05-01

    In the current work, an alternative route for facile synthesis of nanosilver is reported. Oxidized pectin has been used as the reducing agent as well as the stabilizing agent, resulting in the formation of oxidized pectin-nanosilver (OP-NS) core sheath nanohydrogels. The effect of reaction parameters on the synthesized nanoparticles is investigated. The structural and morphological features have been analyzed using X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) respectively. The crystal size of the synthesized nanosilver was calculated to be 28.76 nm. While the average size of the core sheath structure varied from 289 nm to 540 nm, the size of the silver nanoparticle entities at the core varied from 100 nm to 180 nm, with variation in reaction time. From the morphological examination, it could be seen that flower like nanostructures are formed with nanosilver in the core surrounded by a polymeric halo. - Highlights: • In-situ reduction of silver nitrate to nanosilver was carried out using oxidized pectin. • Oxidized pectin-nanosilver nanohydrogels were synthesized. • Nanoparticles with flower like morphology and face centered cubic crystal structure were fabricated.

  13. Characterization of Pectin Nanocoatings at Polystyrene and Titanium Surfaces

    DEFF Research Database (Denmark)

    Gurzawska, Katarzyna; Dirscherl, Kai; Yihua, Yu

    2013-01-01

    wettability, without any major effect on surface roughness (Sa, Sdr). Furthermore, we demonstrated that it is possible to visualize the pectin RG-Is molecules and even the nanocoatings on titanium surfaces, which have not been presented before. The comparison between polystyrene and titanium surface showed...

  14. Engineering of acidic O/W emulsions with pectin

    NARCIS (Netherlands)

    Alba, Katerina; Sagis, L.M.C.; Kontogiorgos, Vassilis

    2016-01-01

    Pectins with distinct molecular design were isolated by aqueous extraction at pH 2.0 or 6.0 and were examined in terms of their formation and stabilisation capacity of model n-alkane–in–water emulsions at acidic pH (pH 2.0). The properties and stability of the resulting emulsions were examined by me

  15. Intermolecular binding of blueberry pectin-rich fractions and anthocyanin.

    Science.gov (United States)

    Lin, Z; Fischer, J; Wicker, L

    2016-03-01

    Pectin was extracted from blueberry powder into three fractions of water soluble (WSF), chelator soluble (CSF) and sodium carbonate soluble (NSF). The fractions were incubated with cyanidin-3-glucoside (C3G), a mixture of five anthocyanidins (cyanidin, pelargonidin, malvidin, petunidin and delphinidin) or blueberry juice at pH 2.0-4.5. Free anthocyanins and bound anthocyanin-pectin mixtures were separated by ultrafiltration. WSF bound the least amount of anthocyanin at all pH values. CSF had stronger anthocyanin binding ability at pH 2.0-3.6, while NSF had stronger anthocyanin binding ability at pH 3.6-4.5. The pectin and anthocyanin binding was lowest at pH 4.5 and higher at pH 2.0-3.6. Nearly doubling C3G pigment content increased bound anthocyanin percentage by 16-23% at pH 3.6, which favored anthocyanin aromatic stacking, compared to 3-9% increase at pH 2.0. Ionic interaction between anthocyanin flavylium cations and free pectic carboxyl groups, and anthocyanin stacking may be two major mechanisms for pectin and anthocyanin binding.

  16. Development of pectin films with pomegranate juice and citric acid.

    Science.gov (United States)

    Azeredo, Henriette M C; Morrugares-Carmona, Rosario; Wellner, Nikolaus; Cross, Kathryn; Bajka, Balazs; Waldron, Keith W

    2016-05-01

    The influence of pomegranate juice (PJ, replacing water as solvent) and citric acid (CA) on properties of pectin films was studied. PJ provided the films with a bright red color, and acted as a plasticizer. Increasing PJ/water ratio from 0/100 to 100/0 resulted in enhanced elongation (from 2% to 20%), decreased strength (from 10 to anthocyanins.

  17. Casein/pectin nanocomplexes as potential oral delivery vehicles.

    Science.gov (United States)

    Luo, Yangchao; Pan, Kang; Zhong, Qixin

    2015-01-01

    Delivery systems prepared with natural biopolymers are of particular interests for applications in food, pharmaceutics and biomedicine. In this study, nanocomplex particles of sodium caseinate (NaCas) and pectin were fabricated and investigated as potential oral delivery vehicles. Nanocomplexes were prepared with three mass ratios of NaCas/pectin by acidification using glucono-δ-lactone and thermal treatment. NaCas/pectin at 1:1 mass ratio resulted in dispersions with the lowest turbidity and the smallest and most uniform nanocomplexes. Thermal treatment at 85 °C for 30 min facilitated the formation of stable, compact, and spherical nanocomplexes. Heating not only greatly increased the yield of nanocomplexes but also significantly improved the encapsulation capability of rutin studied as a model compound. Pectin in nanocomplexes delayed the hydrolysis of NaCas by pepsin at gastric conditions and enabled the controlled release of most rutin in simulated intestinal conditions. The nanocomplexes based on food-sourced biopolymers have promising features for oral delivery of nutrients and medicines.

  18. 菊花破壁饮片的HPLC指纹图谱研究%Study on HPLC Fingerprint of Cell Wall-Broken Decoction Pieces of Chrysanthemi Flos

    Institute of Scientific and Technical Information of China (English)

    刘星云; 王慧玲; 彭丽华; 成金乐

    2016-01-01

    目的:建立菊花破壁饮片HPLC指纹图谱,并分析破壁饮片成品与其中间品、原料的化学成分相关性,为菊花破壁饮片整体质量评价提供依据.方法:采用高效液相色谱法,十八烷基硅烷键合硅胶为填充剂的色谱柱(250 mm×4.6 mm,5μm),以乙腈-0.5%磷酸溶液为流动相进行梯度洗脱,检测波长:348 nm,柱温:35℃.结果:建立了菊花破壁饮片的HPLC指纹图谱,得到了15个共有特征峰,11批样品的相似度达0.98以上,方法学考察结果符合指纹图谱技术要求.结论:所建立的方法稳定、可靠、重复性好,可用于菊花破壁饮片质量控制和综合评价.%Objective:To establish the HPLC fingerprint of Cell Wall-Broken Decoction Pieces of Chrysanthemi Flos, and analyze the relativity between its decoction pieces,broken powder and broken particle,helping to evaluate its quality comprehensively.Methods:RP-HPLC method was performed on an Agilent C18 (250 mm ×4.6 mm,5 μm)column with a gradient elution composed of acetonitrile-aqueous solution containing 0.5% phosphoric acid.The column temperature was set at 35 ℃,while the detective wavelength was set at 348 nm.Results:The chromatographic fingerprint common pattern was established.Fifteen mutual peaks were obtained from the chromatograms of eleven batches of samples.Conclusion:The method with good reproducibility is reliable and stable,which is feasible for quality control of cell wall-broken decoction pieces of Chrysanthemi Flos.

  19. Nephrocalcinosis in Female Rats Fed Diets Containing Either Pectin or Cellulose

    Directory of Open Access Journals (Sweden)

    Ahmed Alhaidary

    2010-01-01

    Full Text Available Problem statement: There is evidence that the type of fiber influences the development of nephrocalcinosis in rats, but the effect of pectin was unknown. Approach: The effects of dietary pectin and cellulose on kidney calcification were studied in female rats. The diets used contained either 0.4-0.6% phosphorus and either cellulose (10%, w/w or pectin. The purified diets used were balanced for residual calcium, magnesium and phosphorus in the fiber preparations. Results: Increasing the phosphorus concentration of the diet from 0.4-0.6% caused massive nephrocalcinosis in rats fed the cellulose diets. Pectin (10%, w/w versus cellulose in diets containing 0.4% phosphorus significantly increased calcium and phosphorus concentrations in kidney. When compared with cellulose, pectin did not influence the apparent absorption of calcium, phosphorus and magnesium. Urinary concentrations of calcium and magnesium were not affected by pectin feeding, but those of phosphorus were increased. When pectin was given with the diet containing 0.6% phosphorus, its nephrocalcinogenic action as compared with cellulose was not observed. Conclusion: Pectin instead of cellulose in diets containing 0.4% phosphorus induced nephrocalcinosis in female rats. The effect of pectin may be explained by an increase in urinary phosphorus concentration. The lack of nephrocalcinogenic action of pectin in a diet with 0.6% phosphorus indicates that the nephrocalcinosis-inducing effect of high phosphorus intake had overruled any effect of fiber type.

  20. Reaction of arracacha genotypes to the root soft rot caused by Pectobacterium chrysanthemi Reação de genótipos de mandioquinha-salsa à podridão-mole das raízes causada por Pectobacterium chrysanthemi

    Directory of Open Access Journals (Sweden)

    Gilmar Paulo Henz

    2005-01-01

    Full Text Available The purpose of this paper was to screen thirty-two arracacha genotypes for their reaction to root soft rot. Twenty roots of each genotype were inoculated with two Pectobacterium chrysanthemi isolates in a randomized experiment (10 roots/isolate. After inoculation, roots were individually wrapped with PVC film and kept at 26ºC in closed plastic bags. Soft rot lesions were recorded after 36 hours and genotypes were grouped in four classes of susceptibility by cluster analysis: 10 were less susceptible, 16 intermediate, 3 susceptible and 3 very susceptible. All the tested arracacha genotypes showed only variation in the degree of susceptibility.O objetivo deste trabalho foi avaliar a reação de 32 genótipos de mandioquinha-salsa à podridão-mole das raízes. Vinte raízes de cada genótipo foram inoculadas com dois isolados de Pectobacterium chrysanthemi em um experimento casualizado (10 raízes/isolado. Após a inoculação, as raízes foram embaladas com filmes de PVC e mantidas a 26ºC em sacos de plástico. As lesões de podridão-mole foram avaliadas após 36 horas e os genótipos agrupados em quatro classes de suscetibilidade por análise de agrupamento: 10 foram menos suscetíveis, 16 intermediários, 3 suscetíveis e 3 muito suscetíveis. Todos os genótipos avaliados demonstraram apenas variação no grau de suscetibilidade.

  1. 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.

  2. Controlled methyl-esterification of pectin catalyzed by cation exchange resin.

    Science.gov (United States)

    Peng, Xiaoxia; Yang, Guang; Fan, Xingchen; Bai, Yeming; Ren, Xiaomeng; Zhou, Yifa

    2016-02-10

    This study developed a new method to methyl-esterify pectin using a cation exchange resin. Homogalacturonan (HG)-type pectin (WGPA-3-HG) and rhamnogalacturonan (RG)-I-type pectin (AHP-RG) obtained from the roots of Panax ginseng and sunflower heads, respectively, were used as models. Compared to commonly used methyl-esterification methods that use either methyl iodide or acidified methanol, the developed method can methyl-esterify both HG- and RG-I-type pectins without degrading their structures via β-elimination or acid hydrolysis. In addition, by modifying reaction conditions, including the mass ratio of resin to pectin, reaction time, and temperature, the degree of esterification can be controlled. Moreover, the resin and methanol can be recycled to conserve resources, lower costs, and reduce environmental pollution. This new methodology will be highly useful for industrial esterification of pectin.

  3. Morphology and ontogeny of the pectines of Babycurus jacksoni (Scorpiones: Buthidae)

    DEFF Research Database (Denmark)

    Funch, Peter; Thybring, Mette

    Pectines are unique mechano- and chemosensory organs of scorpions used in prey capture and mating. All extant species possess one pair of these comb-like sensory structures ventrally on the second mesosomal segment, and each pecten is composed of marginal and medial lamellae that carry numerous...... pectinal teeth with ventral microscopic sensory pegs. Here we studied the ontogeny and morphology of the pectines in the Tanzanian red bark scorpion, Babycurus jacksoni by comparison of size and morphology of their exuvia and pectines from first instar to adult. Light- and scanning electron microscopy...... was unexpec-ted because of the important role of pectines in courtship behaviour. The cuticular spikes found here has not been reported from scorpion pectines before and their function should be further investigated. The undeveloped pegs in the first instar are probably not fully functional in agreement...

  4. 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.

  5. Extraction of pectins with different degrees of esterification from mulberry branch bark.

    Science.gov (United States)

    Liu, Lin; Cao, Jing; Huang, Jian; Cai, Yurong; Yao, Juming

    2010-05-01

    Pectins were extracted from mulberry branch bark, a byproduct of the sericulture industry. A single-factor experiment was used to optimize the production conditions. Under optimal conditions, the galacturonic acid yields from bark with and without epidermis were 61.73 + or - 1.39% and 35.12 + or - 0.24%, respectively. The extracted pectins mainly consisted of galacturonic acid with a trace amount of neutral sugars, and the total galacturonic acid content in the pectins extracted from the bark without epidermis reached 85.46 + or - 2.76%. Pectins extracted from bark without epidermis had a higher degree of esterification (71.13 + or - 1.67%) than those extracted from bark with epidermis (24.27 + or - 2.89%). Pectin solution from bark without epidermis showed higher apparent viscosity, suggesting its higher gelation ability. Thus, the mulberry branch bark is a potential source of pectin with different degrees of esterification.

  6. Pectins esterification in the apoplast of aluminum-treated pea root nodules.

    Science.gov (United States)

    Sujkowska-Rybkowska, Marzena; Borucki, Wojciech

    2015-07-20

    Aiming to elucidate the possible involvement of pectins in aluminum-mediated growth inhibition the distribution of pectins in the apoplast of root nodules was investigated. Experiments were performed on the pea (Pisum sativum L.) root nodules treated with aluminum (50 μM AlCl3, for 2 or 24h). For histochemical acidic pectin localization we used ruthenium red staining. Immunolabeling techniques with monoclonal antibodies specific to high methyl-esterified pectin (JIM7), low methyl-esterified pectin (JIM5) and calcium cross-linked pectin (2F4) were used to re-examine the pattern of pectin esterification and distribution. After immunolabeling the samples were observed using a fluorescent and transmission electron microscope. Ruthenium red staining showed that acid pectin content increased in the apoplast of Al-treated nodules and immunolocalization of pectin epitopes revealed that the fraction of de-esterified pectins increased significantly under Al stress. JIM5 and 2F4 epitopes were located on the inner surface of the primary cell wall with higher intensity at cell corners lining the intercellular spaces and at infection threads (ITs) walls. By contrast, JIM 7 labels all walls uniformly throughout the nodule. In the presence of Al, the increase of JIM5 and 2F4 labeling in thick plant and IT walls, together with a decrease of JIM7 labeling was observed. These results indicate a specific role for pectin de-esterification in the process of wall thickening and growth inhibition. In particular, Al-dependent increase in pectin content and their low methyl esterification degree correlate with wall thickness and higher rigidity, and in this way, may affect IT and nodules growth.

  7. Standard triple, bismuth pectin quadruple and sequential therapies for Helicobacter pylori eradication

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To compare the effectiveness of standard triple, bismuth pectin quadruple and sequential therapies for Helicobacter pylori (H. pylori ) eradication in a randomized, double-blinded, comparative clinical trial in China. METHODS: A total of 215 H. pylori -positive patients were enrolled in the study and randomly allocated into three groups: group A (n = 72) received a 10-d bismuth pectin quadruple therapy (20 mg rabeprazole bid , 1000 mg amoxicillin bid , 100 mg bismuth pectin qid , and 500 mg levofloxaci...

  8. A novel pectin material: extraction, characterization and gelling properties.

    Science.gov (United States)

    Urias-Orona, Vania; Rascón-Chu, Agustin; Lizardi-Mendoza, Jaime; Carvajal-Millán, Elizabeth; Gardea, Alfonso A; Ramírez-Wong, Benjamín

    2010-09-28

    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.

  9. In vivo behavior of hydrogel beads based on amidated pectins.

    Science.gov (United States)

    Munjeri, O; Collett, J H; Fell, J T; Sharma, H L; Smith, A M

    1998-01-01

    Radio-labeled hydrogel beads, based on amidated pectin, have been produced by adding droplets of an amidated pectin solution to calcium chloride. Incorporation of model drugs into the beads and measurement of the dissolution rate showed that the properties of the beads were unaffected by the incorporation of the radiolabel. The labeled beads were used to carry out an in vivo study of their behavior in the gastrointestinal tract using human volunteers. The volunteers were given the beads after an overnight fast and images were obtained at frequent intervals during transit through the upper gastrointestinal tract and the colon. The beads exhibited rapid gastric emptying and proceeded to pass through the small intestine individually before regrouping at the ileo-caecal junction. Once in the colon, the beads again proceeded as individuals and evidence of the degradation of the beads was observed.

  10. 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...

  11. A Novel Pectin Material: Extraction, Characterization and Gelling Properties

    Directory of Open Access Journals (Sweden)

    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.

  12. Pectin/zein beads for potential colon-specific drug delivery: synthesis and in vitro evaluation.

    Science.gov (United States)

    Liu, LinShu; Fishman, Marshall L; Hicks, Kevin B; Kende, Meir; Ruthel, Gordon

    2006-01-01

    Novel complex hydrogel beads were prepared from two edible polymers: pectin, a carbohydrate from citrus fruits, and zein, a protein from corn. The pectin/zein complex hydrogels did not swell in physiological environments, but hydrolyzed in the presence of pectinases. An in vitro study showed the capacity of the hydrogels to endure protease attack and residence time variation. The physical and biological properties of the new hydrogels were attributed to molecular entanglement of the two polymers. The pectin networks were stabilized by the bound zein molecules. In turn, the pectin networks shielded the bound zein from protease digestion.

  13. PECTIN MICROGELS CONTAINING SYNTHETIC POLYMERS BASED ON NANOCAPSULES FOR THE CONTROLLED RELEASE OF INDOMETHACIN

    Directory of Open Access Journals (Sweden)

    Mihaela HOLBAN

    2015-12-01

    Full Text Available Nanocapsule-based Eudragit RS100 and Eudragit E100 containing indomethacin have been prepared. The nanosuspensions have been included into pectin microgels of different polysaccharide concentrations, 28-61 µm-ranged polymer microgels with size and size polydispersity highly depending on the pectin amount being thus obtained. Study of the drug release revealed that indomethacin was released at a slower and more controlled rate from the microgels containing nanocapsules than from the empty pectin microgels. Also, the rate of released indomethacin increased with the augmentation of pectin amount into the microgels.

  14. PREPARATION AND CHARACTERIZATION OF AMIDATED PECTIN BASED POLYMER ELECTROLYTE MEMBRANES

    Institute of Scientific and Technical Information of China (English)

    R.K.Mishra; A.Anis; S.Mondal; M.Dutt; A.K.Banthia

    2009-01-01

    The work presents the synthesis and characterization of ami dated pectin(AP)based polymer electrolyte membranes(PEM)crosslinked with glutaraldehyde(GA).The prepared membranes are characterized by Fourier transform infrared spectroscopy(FTIR),organic elemental analysis,X-ray diffraction studies(XRD),thermogravimetric analysis (TGA)and impedance spectroscopy.Mechanical properties of the membranes are evaluated by tensile tests.The degree of amidation(DA),molar and mass reaction yields(YM and YN)are calculated based on the results of organic elemental analysis.FTIR spectroscopy indicated the presence of primary and secondary amide absorption bands.XRD pattern of membranes clearly indicates that there is a considerable increase in crystallinity as compared to parent pectin.TGA studies indicate that AP is less thermally stable than reference pectin.A maximum room temperature conductivity of 1.098×10-3 Scm-1 is obtained in the membrane,which is designated as AP-3.These properties make them good candidates for low cost biopolymer electrolyte membranes for fuel cell applications.

  15. Robust and versatile pectin-based drug delivery systems.

    Science.gov (United States)

    Marras-Marquez, T; Peña, J; Veiga-Ochoa, M D

    2015-02-20

    Pectin-based resistant, interactive and versatile hydrogel vehicles for oral administration have been prepared. These systems are thought to be versatile enough to allow the inclusion of substances (such as the surfactants tested: Pluronic, Tween, Na Lauryl sulphate) that may contribute to tailor the drug release patterns. Tolbutamide, that shows a discrete and pH-dependent solubility in water, has been employed as a model drug to test the capability of these matrices to overcome such drug-imposed restraints. The incorporation of different surfactants produced pectin-based hydrogels of difficult manipulation. In order to improve this drawback, two different strategies have been developed: blending with agarose or freeze-drying. The presence of agarose yields robust systems that can be handled and tested as prepared, in the fresh state. Freeze-drying not only allows to shape pure pectin and blend systems, but also generates a porous structure whose microstructure, determined by the different components included, influences on the drug release behavior. Tolbutamide release kinetics from freshly prepared matrices can be fitted to the Higuchi model while the freeze-dried ones adjust to the Korsmeyer-Peppas model; hence the hydrogel chains rearrangement processes rule the release during the rehydration process.

  16. Rheological evaluation of the irradiated pectin/gelatin mixed systems

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-07-01

    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)

  17. HecA, a member of a class of adhesins produced by diverse pathogenic bacteria, contributes to the attachment, aggregation, epidermal cell killing, and virulence phenotypes of Erwinia chrysanthemi EC16 on Nicotiana clevelandii seedlings.

    Science.gov (United States)

    Rojas, Clemencia M; Ham, Jong Hyun; Deng, Wen-Ling; Doyle, Jeff J; Collmer, Alan

    2002-10-01

    Erwinia chrysanthemi is representative of a broad class of bacterial pathogens that are capable of inducing necrosis in plants. The E. chrysanthemi EC16 hecA gene predicts a 3,850-aa member of the Bordetella pertussis filamentous hemagglutinin family of adhesins. A hecATn7 mutant was reduced in virulence on Nicotiana clevelandii seedlings after inoculation without wounding. Epifluorescence and confocal laser-scanning microscopy observations of hecA and wild-type cells expressing the green fluorescent protein revealed that the mutant is reduced in its ability to attach and then form aggregates on leaves and to cause an aggregate-associated killing of epidermal cells. Cell killing also depended on production of the major pectate lyase isozymes and the type II, but not the type III, secretion pathway in E. chrysanthemi. HecA homologs were found in bacterial pathogens of plants and animals and appear to be unique to pathogens and universal in necrogenic plant pathogens. Phylogenetic comparison of the conserved two-partner secretion domains in the proteins and the 16S rRNA sequences in respective bacteria revealed the two datasets to be fundamentally incongruent, suggesting horizontal acquisition of these genes. Furthermore, hecA and its two homologs in Yersinia pestis had a G+C content that was 10% higher than that of their genomes and similar to that of plant pathogenic Ralstonia, Xylella, and Pseudomonas spp. Our data suggest that filamentous hemagglutinin-like adhesins are broadly important virulence factors in both plant and animal pathogens.

  18. The Analysis of Saccharides in Chrysanthemi Flos by Capillary Electrophoresis-Amperometric Detection%菊花中糖类组分的毛细管电泳——安培检测研究

    Institute of Scientific and Technical Information of China (English)

    朱金坤; 姚孝林; 郑胜彪; 唐婧

    2012-01-01

    本文采用毛细管区带电泳-安培检测法(CZE-AD),研究了四类菊花中的常见单糖及蔗糖的分离、检测方法。在选定的实验条件下,可在20分钟内实现对葡萄糖、果糖、半乳糖、蔗糖的有效分离;待测糖类在铜电极上具有良好的电流响应、检测灵敏度(LOD:~1.0×10-6mol/L)及适宜的线性范围(5.0×10-6~5.0×10-4mol/L)。实验对滁菊、杭黄菊、贡菊、亳菊中的糖类组分进行了CZE-AD分离检测,方法具有良好的重现性及应用前景。检测结果表明,四类菊花中常见糖类组分的含量差异较大,可为相关植物资源的开发利用提供参考;检测方法简单、快速、有效,可用于菊花中常见糖类成分的测定及质量控制。%In this paper,the determination of normal saccharides in four kinds of Chrysanthemi Flos was investigated with capillary zone electrophoresis-amperometric detection method(CZE-AD).Under the optimized conditions,glucose,fructose,galactose and sucrose could be separated in 20 min.These analyzed saccharides gained excellent current response,detection limits(LOD): ~1.0×10-6mol/L and adequate linear ranges(5.0×10-6~5.0×10-4mol/L).The saccharides in four kinds of Chrysanthemi Flos(Chu-Ju,Hanghuang-Ju,Gong-Ju,Bo-Ju) were analyzed,and the results indicated good reproducibility and applicability of this proposed CZE-AD method.It could be found that the concerns of saccharides varied from one kind of Chrysanthemi Flos to another,and the detection data would provide reference to exploit the corresponding plant resources efficiently.This proposed detection method was simple,quick and effective with potential application in the analysis of saccharides for quality control of Chrysanthemi Flos.

  19. Reinfection and latent infection of Erwinia chrysanthemi pv.zeae in rice%水稻细菌性基腐病菌再侵染和潜伏侵染

    Institute of Scientific and Technical Information of China (English)

    刘琼光; 王振中; 陈玉托; 区伟明; 区肇康

    2003-01-01

    @@ 水稻细菌性基腐病(Erwinia chrysanthemi pv.zeae)近年来在我国局部地区发病加重.有关病菌生物学特性和侵染规律有过一些研究和报道,但病害后期表现症状及病菌的再侵染和潜伏侵染现象等,均未见报道,笔者对此进行了研究.

  20. Characterization, sub-cellular localization and expression profiling of the isoprenylcysteine methylesterase gene family in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Ma Wujun

    2010-09-01

    Full Text Available Abstract Background Isoprenylcysteine methylesterases (ICME demethylate prenylated protein in eukaryotic cell. Until now, knowledge about their molecular information, localization and expression pattern is largely unavailable in plant species. One ICME in Arabidopsis, encoded by At5g15860, has been identified recently. Over-expression of At5g15860 caused an ABA hypersensitive phenotype in transgenic Arabidopsis plants, indicating that it functions as a positive regulator of ABA signaling. Moreover, ABA induced the expression of this gene in Arabidopsis seedlings. The current study extends these findings by examining the sub-cellular localization, expression profiling, and physiological functions of ICME and two other ICME-like proteins, ICME-LIKE1 and ICME-LIKE2, which were encoded by two related genes At1g26120 and At3g02410, respectively. Results Bioinformatics investigations showed that the ICME and other two ICME-like homologs comprise a small subfamily of carboxylesterase (EC 3.1.1.1 in Arabidopsis. Sub-cellular localization of GFP tagged ICME and its homologs showed that the ICME and ICME-like proteins are intramembrane proteins predominantly localizing in the endoplasmic reticulum (ER and Golgi apparatus. Semi-quantitative and real-time quantitative PCR revealed that the ICME and ICME-like genes are expressed in all examined tissues, including roots, rosette leaves, cauline leaves, stems, flowers, and siliques, with differential expression levels. Within the gene family, the base transcript abundance of ICME-LIKE2 gene is very low with higher expression in reproductive organs (flowers and siliques. Time-course analysis uncovered that both ICME and ICME-like genes are up-regulated by mannitol, NaCl and ABA treatment, with ICME showing the highest level of up-regulation by these treatments. Heat stress resulted in up-regulation of the ICME gene significantly but down-regulation of the ICME-LIKE1 and ICME-LIKE2 genes. Cold and dehydration

  1. Chitosan-pectin hybrid nanoparticles prepared by coating and blending techniques.

    Science.gov (United States)

    Rampino, A; Borgogna, M; Bellich, B; Blasi, P; Virgilio, F; Cesàro, A

    2016-03-10

    The preparation of chitosan nanoparticles in combination with pectins, as additional mucoadhesive biopolymers, was investigated. Pectins from apple and from citrus fruit were considered; polygalacturonic acid was taken as a reference. Tripolyphosphate was used as an anionic cross-linker. Two different techniques were compared, namely the coating and the blending. Coated nanoparticles (NPs) in the ratio pectin:NPs from 2:1 to 5:1 evidenced that the size of NPs increased as the amount of pectin (both from apple and citrus fruit) was increased. In particular, for NPs coated with pectin from citrus fruit the size ranges from 200 to 260nm; while for NPs coated with pectin from apple the size ranges from 330 to 450nm. A minimum value of Z-potential around -35mV was obtained for the ratio pectin:NPs 4:1, while further addition of pectin did not decrease the Z-potential. Also blended NPs showed a dependence of the size on the ratio of the components: for a given ratio pectin:tripolyphosphate the size increases as the fraction of chitosan increases; for a low ratio chitosan:pectin a high amount of tripolyphosphate was needed to obtain a compact structure. The effect of the additional presence of loaded proteins in chitosan-pectin nanoparticles was also investigated, since proteins contribute to alter the electrostatic interactions among charged species. FT-IR and DSC characterization are presented to confirm the interactions between biopolymers. Finally, the biocompatibility of the used materials was assessed by the chorioallantoic membrane assay, confirming the safety of the materials.

  2. Dietary Pectin Increases Intestinal Crypt Stem Cell Survival following Radiation Injury.

    Directory of Open Access Journals (Sweden)

    Sripathi M Sureban

    Full Text Available Gastrointestinal (GI mucosal damage is a devastating adverse effect of radiation therapy. We have recently reported that expression of Dclk1, a Tuft cell and tumor stem cell (TSC marker, 24h after high dose total-body gamma-IR (TBI can be used as a surrogate marker for crypt survival. Dietary pectin has been demonstrated to possess chemopreventive properties, whereas its radioprotective property has not been studied. The aim of this study was to determine the effects of dietary pectin on ionizing radiation (IR-induced intestinal stem cell (ISC deletion, crypt and overall survival following lethal TBI. C57BL/6 mice received a 6% pectin diet and 0.5% pectin drinking water (pre-IR mice received pectin one week before TBI until death; post-IR mice received pectin after TBI until death. Animals were exposed to TBI (14 Gy and euthanized at 24 and 84h post-IR to assess ISC deletion and crypt survival respectively. Animals were also subjected to overall survival studies following TBI. In pre-IR treatment group, we observed a three-fold increase in ISC/crypt survival, a two-fold increase in Dclk1+ stem cells, increased overall survival (median 10d vs. 7d, and increased expression of Dclk1, Msi1, Lgr5, Bmi1, and Notch1 (in small intestine post-TBI in pectin treated mice compared to controls. We also observed increased survival of mice treated with pectin (post-IR compared to controls. Dietary pectin is a radioprotective agent; prevents IR-induced deletion of potential reserve ISCs; facilitates crypt regeneration; and ultimately promotes overall survival. Given the anti-cancer activity of pectin, our data support a potential role for dietary pectin as an agent that can be administered to patients receiving radiation therapy to protect against radiation-induces mucositis.

  3. Dietary Pectin Increases Intestinal Crypt Stem Cell Survival following Radiation Injury.

    Science.gov (United States)

    Sureban, Sripathi M; May, Randal; Qu, Dongfeng; Chandrakesan, Parthasarathy; Weygant, Nathaniel; Ali, Naushad; Lightfoot, Stan A; Ding, Kai; Umar, Shahid; Schlosser, Michael J; Houchen, Courtney W

    2015-01-01

    Gastrointestinal (GI) mucosal damage is a devastating adverse effect of radiation therapy. We have recently reported that expression of Dclk1, a Tuft cell and tumor stem cell (TSC) marker, 24h after high dose total-body gamma-IR (TBI) can be used as a surrogate marker for crypt survival. Dietary pectin has been demonstrated to possess chemopreventive properties, whereas its radioprotective property has not been studied. The aim of this study was to determine the effects of dietary pectin on ionizing radiation (IR)-induced intestinal stem cell (ISC) deletion, crypt and overall survival following lethal TBI. C57BL/6 mice received a 6% pectin diet and 0.5% pectin drinking water (pre-IR mice received pectin one week before TBI until death; post-IR mice received pectin after TBI until death). Animals were exposed to TBI (14 Gy) and euthanized at 24 and 84h post-IR to assess ISC deletion and crypt survival respectively. Animals were also subjected to overall survival studies following TBI. In pre-IR treatment group, we observed a three-fold increase in ISC/crypt survival, a two-fold increase in Dclk1+ stem cells, increased overall survival (median 10d vs. 7d), and increased expression of Dclk1, Msi1, Lgr5, Bmi1, and Notch1 (in small intestine) post-TBI in pectin treated mice compared to controls. We also observed increased survival of mice treated with pectin (post-IR) compared to controls. Dietary pectin is a radioprotective agent; prevents IR-induced deletion of potential reserve ISCs; facilitates crypt regeneration; and ultimately promotes overall survival. Given the anti-cancer activity of pectin, our data support a potential role for dietary pectin as an agent that can be administered to patients receiving radiation therapy to protect against radiation-induces mucositis.

  4. 超高压技术对草莓汁果胶甲酯酶钝化作用的研究%Study on high pressure(HP) treatments on Pectin methylesterase(PME)activity in strawberry beverage

    Institute of Scientific and Technical Information of China (English)

    张波波; 王丹; 马越; 张超; 赵晓燕; 霍乃蕊

    2013-01-01

    研究不同条件超高压处理及超高温瞬时灭菌(UHT)对调配草莓汁果胶甲酯酶(PME)钝化作用的影响.以完成调配的草莓汁为对照,分别考察处理压力、保压时间、协同温度以及处理次数对样品的影响.结果表明,不同超高压处理及UHT处理与对照组相比都能导致PME酶活性降低(p<0.05).200、400MPa(30℃,20mm)处理对PME钝化效果与UHT处理相当,达到一定压力(600MPa)钝化效果明显强于UHT处理;超高压处理时间越长,PME钝化效果越明显;超高压协同温度30~60℃处理对PME钝化无显著差异;超高压处理时间一定,增加处理次数对PME钝化作用不明显.贮藏30d后,不同处理PME酶活性基本无变化.

  5. Expression Analysis of Pectin Methylesterase Genes in Postharvest Longan Fruit during Aril Breakdown%采后龙眼果肉自溶过程中PME基因的表达分析

    Institute of Scientific and Technical Information of China (English)

    赵明磊; 邝健飞; 陆旺金; 陈建业

    2011-01-01

    采用RT-PCR和RACE-PCR相结合的方法,研究了果胶甲酯酶基因(PME)表达与采后龙眼(Dimocarpus longan Lour.)果肉自溶的关系.从龙眼果实中分离得到3个包含3'非翻译区的PME基因片段,分别命名为DlPME1、DlPME2和DlPME3,其推导的氨基酸序列与多种植物的PME蛋白有较高的同源性.采用半定量RT-PCR的方法分析了常温(22℃)和低温(4℃)贮藏下的龙眼果肉自溶过程中3个PME基因的表达特征,结果表明:常温贮藏下,果肉自溶过程中DlPME1的表达逐渐减弱,DlPME2和DlPME3的表达先增高后降低;低温贮藏下,果肉自溶过程中DlPMEl和DlPME3的表达先增强后降低,而DlPME2的表达持续减弱.这些表明,龙眼果实PME基因在常温和低温下的果肉自溶中可能具有不同的响应机制,常温下可能与DlPME2和DlPME3的表达有关,而低温下可能与DlPME1和DlPME3的表达有关.

  6. High performance liquid chromatography time of flight electrospray ionization mass spectrometry for quantification of sesquiterpenes in Chrysanthemi indici Flos active extract

    Science.gov (United States)

    Fu, Ling; Wang, Pan; Sun, Yiqun; Wang, Yangyang; Zhao, Jing; Ye, Yuting; Zhang, Yanbin; Bi, Yuefeng

    2015-01-01

    Background: Chrysanthemi indici Flos, a traditional herbal medicine is used to clearing heat–toxicity, removing the liver fire, and improving eyesight. In our preliminary work, an active extract of CTC in C. An indici Flos with anti-hepatitis B virus and liver protective activity was found by HepG2.2.1.5 test and experiment of protein synthesis in mice's injured liver. In this work, we aimed to study the active faction CTC further by qualitative and quantitative analysis method. Materials and Methods: High performance liquid chromatography time of flight electrospray ionization mass spectrometry (HPLC TOF ESI-MS) analysis method of the CTC was established. Cumambrin A and angeloylcumambrin B in CTC were analyzed by high performance liquid chromatography-ultraviolet-evaporative light scattering detector (HPLC-UV-ELSD) analysis methods. A binary gradient elution program was conducted for chromatographic separation with acetonitrile (A) and ultrapure water (B) as follows: 0–10 min, 42–46% A; 10–20 min, 46–55% A; 20–25 min, 55–60% A; and 25–35 min, 60–75% A. The column temperature and UV wavelength were set at 30°C and 205 nm. Result: Ten constituents including (3R, 5R, 6S, 7S, 10R)-7-(2-hydroxy-2-propyl)-10-methyl-4-methyleneperhy, dronaphthal-ene-3, 5, 6-triol acetone solvate; (+)-edusmance-4, (14)-ene-11, 13-diol; linarin; luteolin; apigenin; tricin; 5, 3’,4’- trimethyl-6,7-dimethoxy flavones; cumambrin A; acacetin; and angeloylcumambrin B in CTC were identified by HPLC TOF ESI-MS. The contents of sesquiterpenes in CTC were decreased by storing years. Conclusions: The results showed that both UV and ELSD methods were feasible, accurate, and the determination results were in good consistency. The contents of two sesquiterpenes decreased with storing years. Two sesquiterpenes could be used as quality control for C. indici flos CTC. PMID:26600718

  7. 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...

  8. 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

  9. 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 visco

  10. Characterisation of biodegradable pectin aerogels and their potential use as drug carriers.

    Science.gov (United States)

    Veronovski, Anja; Tkalec, Gabrijela; Knez, Željko; Novak, Zoran

    2014-11-26

    The purpose of this work was to prepare stable citrus (CF) and apple (AF) pectin aerogels for potential pharmaceutical applications. Different shapes of low ester pectin aerogels were prepared by two fundamental methods of ionic cross-linking. Pectins' spherical and multi-membrane gels were first formed by the diffusion method using 0.2M CaCl2 solution as an ionic cross-linker. The highest specific surface area (593 m(2)/g) that had so far been reported for pectin aerogels was achieved using this method. Monolithic pectin gels were formed by the internal setting method. Pectin gels were further converted into aerogels by supercritical drying using CO2. As surface area/volume is one of the key parameters in controlling drug release, multi-membrane pectin aerogels were further used as drug delivery carriers. Theophylline and nicotinic acid were used as model drugs for the dissolution study. CF aerogels showed more controlled release behaviour than AF pectin aerogels. Moreover a higher release rate (100%) was observed with CF aerogels.

  11. 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.

  12. 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.

  13. 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 a

  14. 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

  15. An experimental design approach to the chemical characterisation of pectin polysaccharides extracted from Cucumis melo Inodorus.

    Science.gov (United States)

    Denman, Laura J; Morris, Gordon A

    2015-03-06

    Extracted pectins have been utilised in a number of applications in both the food and pharmaceutical industries where they are generally used as gelling agents, thickeners and stabilisers, although a number of pectins have been shown to be bioactive. These functional properties will depend upon extraction conditions. A statistical experimental design approach was used to study the effects of extraction conditions pH, time and temperature on pectins extracted from Cucumis melo Inodorus. The results show that the chemical composition is very sensitive to these conditions and that this has a great influence on for example the degree of branching. Higher temperatures, lower pHs and longer extraction times lead to a loss of the more acid labile arabinofuranose residues present on the pectin side chain. The fitting of regression equations relating yield and composition to extraction conditions can therefore lead to tailor-made pectins for specific properties and/or applications.

  16. 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...

  17. Adsorptional photocatalytic degradation of methylene blue onto pectin-CuS nanocomposite under solar light.

    Science.gov (United States)

    Gupta, Vinod Kumar; Pathania, Deepak; Agarwal, Shilpi; Singh, Pardeep

    2012-12-01

    This study describes the effect of adsorption on methylene blue degradation using pectin-CuS nanocomposite (PCSNC). The nanocomposite was synthesized using co-precipitation methods followed by direct encapsulation with pectin. The synthesized nanocomposite was characterized by SEM, TEM, XRD, FTIR and UV-vis spectral technique. The adsorption and photocatalytic efficiencies of PCSNC were compared with copper sulphide nanoparticle (CSNP). The dye removal was studied under different reaction conditions. The adsorption capacity of pectin based nanocomposite was higher due to other free functional group on pectin surface after connecting to nanoparticles. The simultaneous adsorption and photodegradation process (A+P) was the most efficient process due to rapid destruction of adsorbed dye molecules. The complete COD removal was attained in 10h using PCSNC/A+P process. On comparing with CSNP, pectin-CuS nano composite showed more degradation efficiency and reusability for MB degradation.

  18. 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.

  19. Studies on pectins as potential hydrogel matrices for controlled-release drug delivery.

    Science.gov (United States)

    Sungthongjeen, S; Pitaksuteepong, T; Somsiri, A; Sriamornsak, P

    1999-12-01

    Polymeric hydrogels are widely used as controlled-release matrix tablets. In the present study, we investigated high-methoxy pectins for their potential value in controlled-release matrix formulations. The effects of compression force, ratio of drug to pectin, and type of pectin on drug release from matrix tablets were also investigated. The results of the in vitro release studies show that the drug release from compressed matrix tablets prepared from pectin can be modified by changing the amount and the type of pectin in the matrix tablets. However, compression force did not significantly affect the drug release. The mechanisms controlling release rate were discussed with respect to drug diffusion through the polymer matrices, but may be more complex.

  20. Anti-cancer activities of pH- or heat-modified pectin

    Directory of Open Access Journals (Sweden)

    Lionel eLeclere

    2013-10-01

    Full Text Available Despite enormous efforts that have been made in the search for novel drugs and treatments, cancer continues to be a major public health problem. Moreover, the emergence of resistance to cancer chemotherapy often prevents complete remission. Researchers have thus turned to natural products mainly from plant origin to circumvent resistance. Pectin and pH- or heat-modified pectin have demonstrated chemopreventive and antitumoral activities against some aggressive and recurrent cancers. The focus of this review is to describe how pectin and modified pectin display these activities and what are the possible underlying mechanisms. The failure of conventional chemotherapy to reduce mortality as well as serious side effects makes natural products, such as pectin-derived products, ideal candidates for exerting synergism in combination with conventional anticancer drugs.

  1. 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

    Pectin production is complex, and final product quality assessment is generally accomplished at the end of the process using time-consuming off-line laboratory analysis. In this study, pectin was extracted from lime peel either by acid or by enzymes. Fourier transform infrared spectroscopy...... 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...

  2. 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.

  3. Development and in vitro evaluation of a buccal drug delivery system based on preactivated thiolated pectin.

    Science.gov (United States)

    Hauptstein, Sabine; Hintzen, Fabian; Müller, Christiane; Ohm, Moritz; Bernkop-Schnürch, Andreas

    2014-11-01

    The aim of this study was to evaluate the potential of preactivated thiolated pectin (Pec-Cys-MNA) for buccal drug delivery. Therefore, a gel formulation containing this novel polymer and the model drug lidocaine was prepared and investigated in vitro in terms of rheology, mucoadhesion, swelling behavior and drug release in comparison to formulations based on pectin (Pec) and thiolated pectin (Pec-Cys). Both pectin derivatives showed gel formation without addition of any other excipient due to self-crosslinking thiol groups. Under same conditions, pectin did not show gel formation. Viscosity of Pec-Cys-based formulation increased 92-fold and viscosity of Pec-Cys-MNA-based formulations by 4958-fold compared to pectin-based formulation. Gels did not dissolve in aqueous environment during several hours and were able to take up water. Mucoadhesion of pectin on buccal tissue could be improved significantly, value of total work of adhesion increased in the following rank order: Pec-Cys-MNA > Pec-Cys > Pec. The retention time of a model drug incorporated in gel formulations on buccal mucosa under continuous rinsing with phosphate-buffered saline was prolonged, after 1.5 h 3-fold higher amount of a model drug was to be found on tissue after application of Pec-Cys-MNA-based formulation compared to pectin-based and 2-fold compared to Pec-Cys-based formulation. The Pec-Cys-MNA-based gel showed a more sustained release of lidocaine than Pec-Cys-based gel, whereas pectin solution revealed an immediate release. According to these results, the self-crosslinking pectin-derivative is a promising tool for buccal application.

  4. Encapsulated Escherichia coli in alginate beads capable of secreting a heterologous pectin lyase

    Directory of Open Access Journals (Sweden)

    Trikka Fotini A

    2005-12-01

    Full Text Available Abstract Background Production of heterologous proteins in the E. coli periplasm, or into the extracellular fluid has many advantages; therefore naturally occurring signal peptides are selected for proteins translocation. The aim of this study was the production in high yields of a recombinant pectin lyase that is efficiently secreted and the encapsulation of transformed E. coli cells for pectin degradation in a biotechnological process. Results The nucleotide sequence of Bacillus subtilis α-amylase's signal peptide was fused to the N-terminal of an heterologously expressed pectin lyase in E. coli BL21 [DE3]. Thus pectin lyase secretion was achieved into the extracellular growth medium. E. coli cells harboring the recombinant plasmid heterologously express pectin lyase to around 22% of the total cellular proteins, as it was estimated by SDS-PAGE and image analysis. IPTG induces the heterologously expressed enzyme, which is initially distributed extracellularly (7 hour and later on at the periplasmic (9 hours or cytosolic fraction (20 hours. No pectin lyase activity was found in the membranes fraction and in the inclusion bodies. Encapsulation of the recombinant strains of E. coli in alginate or alginate/silica beads 1:5 showed that pectin lyase could degrade effectively its substrate, for at least ten operational cycles. Conclusion Secretion of an heterologously overexpressed pectin lyase in E. coli BL21 [DE3] was achieved in this study. For this purpose the signal peptide of α-amylase from B. subtilis was fused to the N-terminal domain of pectin lyase. Encapsulated E. coli BL21 [DE3] cells harboring pET29c/exPNL were used successfully for pectin degradation up to ten operational cycles indicating that under special conditions this might have biotechnological implementations.

  5. 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

  6. 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.

  7. Degradation of different pectins by fungi: correlations and contrasts between the pectinolytic enzyme sets identified in genomes and the growth on pectins of different origin

    Directory of Open Access Journals (Sweden)

    Benoit Isabelle

    2012-07-01

    Full Text Available Abstract Background Pectins are diverse and very complex biomolecules and their structure depends on the plant species and tissue. It was previously shown that derivatives of pectic polymers and oligosaccharides from pectins have positive effects on human health. To obtain specific pectic oligosaccharides, highly defined enzymatic mixes are required. Filamentous fungi are specialized in plant cell wall degradation and some produce a broad range of pectinases. They may therefore shed light on the enzyme mixes needed for partial hydrolysis. Results The growth profiles of 12 fungi on four pectins and four structural elements of pectins show that the presence/absence of pectinolytic genes in the fungal genome clearly correlates with their ability to degrade pectins. However, this correlation is less clear when we zoom in to the pectic structural elements. Conclusions This study highlights the complexity of the mechanisms involved in fungal degradation of complex carbon sources such as pectins. Mining genomes and comparative genomics are promising first steps towards the production of specific pectinolytic fractions.

  8. Characterization of Pectin Nanocoatings at Polystyrene and Titanium Surfaces

    DEFF Research Database (Denmark)

    Gurzawska, Katarzyna; Dirscherl, Kai; Yihua, Yu;

    2013-01-01

    study was to physically characterize and compare polystyrene and titanium surfaces nanocoated with different Rhamnogalacturonan-Is (RG-I) and to visualize RG-I nanocoatings. RG-Is from potato and apple were coated on aminated surfaces of polystyrene, titianium discs and titanium implants...... wettability, without any major effect on surface roughness (Sa, Sdr). Furthermore, we demonstrated that it is possible to visualize the pectin RG-Is molecules and even the nanocoatings on titanium surfaces, which have not been presented before. The comparison between polystyrene and titanium surface showed...

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

    Science.gov (United States)

    Maxwell, Ellen G; Colquhoun, Ian J; Chau, Hoa K; Hotchkiss, Arland T; Waldron, Keith W; Morris, Victor J; Belshaw, Nigel J

    2016-01-20

    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 have been compared. Pectin extracted from sugar beet pulp only weakly affected the viability of colon cancer cells. Alkali treatment increased the anti-cancer effect of sugar beet pectin via an induction of apoptosis. Alkali treatment decreased the degree of esterification (DE) and increased the ratio of rhamnogalacturonan I (RGI) to homogalacturonan. Low DE per se did not play a significant role in the anti-cancer activity. However, the enzymatic removal of galactose and, to a lesser extent, arabinose from the pectin decreased the effect on cancer cells indicating that the neutral sugar-containing RGI regions are important for pectin bioactivity.

  10. Performance evaluation of pectin as ecofriendly corrosion inhibitor for X60 pipeline steel in acid medium: experimental and theoretical approaches.

    Science.gov (United States)

    Umoren, Saviour A; Obot, Ime B; Madhankumar, A; Gasem, Zuhair M

    2015-06-25

    The corrosion inhibition effect of pectin (a biopolymer) for X60 pipeline steel in HCl medium was investigated using weight loss, electrochemical, water contact angle measurements, and scanning electron microscopy techniques. The results obtained show that pectin acts as a good corrosion inhibitor for X60 steel. Inhibition efficiency increased with increase in pectin concentration and temperature. Potentiodynamic polarization results reveal that pectin could be classified as a mixed-type corrosion inhibitor with predominant control of the cathodic reaction. The effective corrosion inhibition potential of pectin could be related to the adsorption of pectin molecules at the metal/solution interface which is found to accord with the Langmuir adsorption isotherm model and a protective film formation. Quantum chemical calculations provided insights into the active sites and reactivity parameters governing pectin activity as a good corrosion inhibitor for X60 steel.

  11. Biodegradation and ecotoxicological assessment of pectin production wastewater

    Institute of Scientific and Technical Information of China (English)

    V. Reginatto; E. R. Amante; K. Gerhardy; S. Kunst; N. Duran

    2009-01-01

    In this study,the chemical composition of pectin production wastewater and its toxicity during biological treatment were investigated.Samples of wastewater from different steps of a pectin production wastewater biological treatment plant were investigated including the influent of the treatment (1),after denitrification tank (2),after anaerobic treatment (3) and final effluent (4).The conventional physico-chemical characteristics of samples did not indicate wastewater toxicity.However,toxicity assessments carried out on Vibrio fischeri and Scenedesmus subspicatus indicated low EC50 values.The fractionation of the samples using an XAD resin showed that the toxicity was associated with the organic matter.Wastewater apparent molecular mass distributions were 14.3,25.0,24.4 and 29.6 kDa for samples 1 to 4,respectively.Finally,characteristics of the sample by pyrolisis-gas chromatography-mass spectrometry (Py-CG-MS) demonstrated its polyphenolic nature and a 23% increase in the levels of such compounds after the first biological treatment step.

  12. Pectin-based colon-specific drug delivery

    Directory of Open Access Journals (Sweden)

    Shailendra Shukla

    2011-01-01

    Full Text Available Colon-specific drug delivery have a great importance in the delivery of drugs for the treatment of local colonic, as well as systemic diseases like Crohn′s disease, ulcerative colitis, colorectal cancer, amoebiasis, asthma, arthritis and inflammation which can be achieved by targeted delivery of drug to colon. Specific systemic absorption in the colon gave interesting possibilities for the delivery of protein and peptides. It contains relatively less proteolytic enzyme activities in the colon compared to the upper gastrointestinal tract (GIT. Recommended treatments included the administration of anti-inflammatory drugs, chemotherapeutic agents and antibiotics which must be released in the colon. Pectin is a naturally occurring polysaccharide has in recent years gained increasingly in importance in advance drug delivery. It was employed in pharmaceutical industry, health promotion and treatment. Owing to its gelling properties it has been used potentially as a carrier for drug delivery to the GIT, such as matrix tablets, gel beads, film-coated dose form. This review will discuss the important chemistry and general properties of pectin, its gel formation mechanism properties and its uses in novel drug delivery to the colon.

  13. Pectin matrix as oral drug delivery vehicle for colon cancer treatment.

    Science.gov (United States)

    Wong, Tin Wui; Colombo, Gaia; Sonvico, Fabio

    2011-03-01

    Colon cancer is the fourth most common cancer globally with 639,000 deaths reported annually. Typical chemotherapy is provided by injection route to reduce tumor growth and metastasis. Recent research investigates the oral delivery profiles of chemotherapeutic agents. In comparison to injection, oral administration of drugs in the form of a colon-specific delivery system is expected to increase drug bioavailability at target site, reduce drug dose and systemic adverse effects. Pectin is suitable for use as colon-specific drug delivery vehicle as it is selectively digested by colonic microflora to release drug with minimal degradation in upper gastrointestinal tract. The present review examines the physicochemical attributes of formulation needed to retard drug release of pectin matrix prior to its arrival at colon, and evaluate the therapeutic value of pectin matrix in association with colon cancer. The review suggests that multi-particulate calcium pectinate matrix is an ideal carrier to orally deliver drugs for site-specific treatment of colon cancer as (1) crosslinking of pectin by calcium ions in a matrix negates drug release in upper gastrointestinal tract, (2) multi-particulate carrier has a slower transit and a higher contact time for drug action in colon than single-unit dosage form, and (3) both pectin and calcium have an indication to reduce the severity of colon cancer from the implication of diet and molecular biology studies. Pectin matrix demonstrates dual advantages as drug carrier and therapeutic for use in treatment of colon cancer.

  14. Adsorption of Cd(II) by two variable-charge soils in the presence of pectin.

    Science.gov (United States)

    Wang, Ru-Hai; Zhu, Xiao-Fang; Qian, Wei; Zhao, Min-Hua; Xu, Ren-Kou; Yu, Yuan-Chun

    2016-07-01

    Batch experiments were conducted to investigate cadmium(II) (Cd(II)) adsorption by two variable-charge soils (an Oxisol and an Ultisol) as influenced by the presence of pectin. When pectin dosage was less than 30 g kg(-1), the increase in Cd(II) adsorption with the increasing dose of pectin was greater than that when the pectin dosage was >30 g kg(-1). Although both Langmuir and Freundlich equations fitted the adsorption isotherms of Cd(II) and electrostatic adsorption data of Cd(II) by the two soils well, the Langmuir equation showed a better fit. The increase in the maximum total adsorption of Cd(II) induced by pectin was almost equal in both the soils, whereas the increase in the maximum electrostatic adsorption of Cd(II) was greater in the Oxisol than in the Ultisol because the former contained greater amounts of free Fe/Al oxides than the latter, which, in turn, led to a greater increase in the negative charge on the Oxisol. Therefore, the presence of pectin induced the increase in Cd(II) adsorption by the variable-charge soils mainly through the electrostatic mechanism. Pectin increased the adsorption of Cd(II) by the variable-charge soils and thus decreased the activity and mobility of Cd(II) in these soils.

  15. 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.

  16. Evaluation of Pectin derived from Orange peel as a Pharmaceutical Excipient

    Directory of Open Access Journals (Sweden)

    M Ravindrakullai reddy

    2013-06-01

    Full Text Available The objective of the present work is extraction of pectin from waste of orange fruit peel and further characterization for useful alternative pharmaceutical excipient. The pectin was subjected to phytochemical and physicochemical characterization of its safety and suitability to use as binding and suspending agent. FT-IR spectroscopy, DSC studies were performed for drug, orange peel pectin powder, prepared tablet and suspension formulations. Aceclofenac tablets were prepared by wet granulation method containing mannitol as diluent; using 2.5, 5, 7.5 and 10 %w/w of orange peel pectin powder and 7.5 %w/w of PVP (reference as binding agents in the tablet formulation. Aceclofenac suspensions were prepared with orange peel pectin powder at 0.5, 1, 1.5 and 2 %w/v as suspending agent and 1.5 %w/v of sodium CMC as reference suspending agent. Pharmaceutical properties of granules and tablets such as carr’s index, Haunser’s ratio and angle of repose and post compression parameters like friability, hardness, and disintegration time studies were determine and found satisfactory. The evaluation test of suspension like sedimentation volume, redispersibility, pH, degree of flocculation were found satisfactory. In vitro release studies shows that release rate of drug is decreased with increase in the orange peel pectin powder percentage in the formulation. Orange peel pectin powder showed good binding and suspending properties at 10 %w/w and 2 %w/v, respectively.

  17. CaSO4 and cationic polyelectrolyte as possible pectin precipitants in sugar beet juice clarification

    Directory of Open Access Journals (Sweden)

    Kuljanin Tatjana

    2015-01-01

    Full Text Available Three pectin preparations were isolated from fresh sugar beet pulp during the 150 minutes of extraction, at pH values of 1, 3.5 and 8.5. CaSO4 precipitant was added to 100 cm3 of 0.1% (wt solution of pectin. Studies were performed with 9 different concentrations of CaSO4 solution (50-450 mg dm-3 with the addition of a cationic polyelectrolyte (cationic PAM in concentrations of 3 and 5 mg dm-3. The efficiency of pectin precipitation was monitored by measuring the zeta potential of pectin preparations. Optimal amounts of precipitant CaSO4, without the use of a cationic polyelectrolyte, were as follows: 490-678 mg CaSO4/g pectin. After the use of a cationic polyelectrolyte, the optimal amounts of CaSO4 were smaller (353-512 mg/g pectin. These quantities are significantly lower than the average amount of CaO used in the conventional clarification process of sugar beet juice (about 9 g/g pectin of sugar beet juice. [Projekat Ministarstva nauke Republike Srbije, br. TR -31055

  18. Effect of extraction conditions on the yield and chemical properties of pectin from cocoa husks.

    Science.gov (United States)

    Chan, Siew-Yin; Choo, Wee-Sim

    2013-12-15

    Different extraction conditions were applied to investigate the effect of temperature, extraction time and substrate-extractant ratio on pectin extraction from cocoa husks. Pectin was extracted from cocoa husks using water, citric acid at pH 2.5 or 4.0, or hydrochloric acid at pH 2.5 or 4.0. Temperature, extraction time and substrate-extractant ratio affected the yields, uronic acid contents, degrees of methylation (DM) and degrees of acetylation (DA) of the extracted pectins using the five extractants differently. The yields and uronic acid contents of the extracted pectins ranged from 3.38-7.62% to 31.19-65.20%, respectively. The DM and DA of the extracted pectins ranged from 7.17-57.86% to 1.01-3.48%, respectively. The highest yield of pectin (7.62%) was obtained using citric acid at pH 2.5 [1:25 (w/v)] at 95 °C for 3.0 h. The highest uronic acid content (65.20%) in the pectin was obtained using water [1:25 (w/v)] at 95 °C for 3.0 h.

  19. Acetylesterase-Mediated Deacetylation of Pectin Impairs Cell Elongation, Pollen Germination, and Plant Reproduction

    Energy Technology Data Exchange (ETDEWEB)

    Gou J. Y.; Liu C.; Miller, L. M.; Hou, G.; Yu, X.-H.; Chen, X.-Y.

    2012-01-01

    Pectin is a major component of the primary cell wall of higher plants. Some galacturonyl residues in the backbone of pectinaceous polysaccharides are often O-acetylated at the C-2 or C-3 position, and the resulting acetylesters change dynamically during the growth and development of plants. The processes involve both enzymatic acetylation and deacetylation. Through genomic sequence analysis, we identified a pectin acetylesterase (PAE1) from black cottonwood (Populus trichocarpa). Recombinant Pt PAE1 exhibited preferential activity in releasing the acetate moiety from sugar beet (Beta vulgaris) and potato (Solanum tuberosum) pectin in vitro. Overexpressing Pt PAE1 in tobacco (Nicotiana tabacum) decreased the level of acetyl esters of pectin but not of xylan. Deacetylation engendered differential changes in the composition and/or structure of cell wall polysaccharides that subsequently impaired the cellular elongation of floral styles and filaments, the germination of pollen grains, and the growth of pollen tubes. Consequently, plants overexpressing PAE1 exhibited severe male sterility. Furthermore, in contrast to the conventional view, PAE1-mediated deacetylation substantially lowered the digestibility of pectin. Our data suggest that pectin acetylesterase functions as an important structural regulator in planta by modulating the precise status of pectin acetylation to affect the remodeling and physiochemical properties of the cell wall's polysaccharides, thereby affecting cell extensibility.

  20. CHEMICAL MODIFICATION AND CHARACTERIZATION OF PECTIN AS A POTENTIAL DRUG RELEASE RETARDANT

    Directory of Open Access Journals (Sweden)

    Harika Puppala Satya Krishna

    2011-02-01

    Full Text Available The present study deals with the chemical modification of pectin by acetylation of their free hydroxyl groups to yield high ester pectin and to evaluate its solubility and swelling behaviour along with the effect on the release pattern of the drug. Modified pectins were prepared by acetylation process using various strengths of 20%, 40% and 60% v/v acetyl chloride in ethanol. The prepared modified pectins were subjected to various physico-chemical characteristics like solubility, gelling studies, acid value, saponification value and ester value. FTIR studies were carried out to confirm the chemical modification of pectin. Matrix tablets of tramadol were formulated using various strengths of modified pectins in different concentrations and its impact on drug release was studied. All the formulated batches were subjected to weight variation, hardness, friability, drug content and the values obtained were within the acceptable range. The in-vitro drug release characteristics from the formulated tablets were compared with commercial sustained release tablet of tramadol. The optimized tablet formulation F4 sustained the drug release over a period of 8hours as comparable to the marketed product. Thus the synthesized modified pectin proved to be an ideal drug release retarding polymer.

  1. Stabilisation of strawberry (Fragaria x ananassa Duch.) anthocyanins by different pectins.

    Science.gov (United States)

    Buchweitz, M; Speth, M; Kammerer, D R; Carle, R

    2013-12-01

    The objective of the present study was to evaluate the effects of different pectins on strawberry anthocyanins in viscous model solutions at pH 3.0. For this purpose, low esterified amidated, low and high methyl esterified citrus and apple pectins, and a sugar beet pectin (SBP), respectively, were added to strawberry extracts. The latter were predominantly composed of pelargonidin-glycosides, containing either reduced (E-1) or original amounts of non-anthocyanin phenolics (E-2). Model systems were stored for 18 weeks at 20±0.5 °C protected from light, and anthocyanins were quantitated in regular intervals by HPLC-DAD analyses. Half-life (t1/2) and destruction (D) values were calculated based on first-order kinetics. Generally, significant differences in pigment retention could be ascribed to differing pectin sources, while variation in the degree of esterification and amidation, respectively, had negligible effects. Compared to systems without added pectin, apple pectins and SPB enhanced anthocyanin stability moderately, while stabilising effects of citrus pectins were poor or even imperceptible. Generally, the amount of non-anthocyanin phenolics and the addition of citrate did not markedly affect anthocyanin stability. However, pectins had no influence on total phenolic contents (Folin-Ciocalteu assay) and antioxidant capacities (FRAP and TEAC assay) of strawberry phenolics over time. For pelargonidin-3-glucoside and -rutinoside largely consistent stabilities were found in all model systems. In contrast, pelargonidin-3-malonylglucoside was less stable in the blank, and stabilisation by pectins was always negligible. The findings of the present study are contrary to results reported previously for the stabilisation of cyanidin- and delphinidin-glycosides in similar model systems prepared with black currant extracts, indicating a high impact of the number of hydroxyl groups in the anthocyanin B-ring.

  2. Pectin-cysteine conjugate: synthesis and in-vitro evaluation of its potential for drug delivery.

    Science.gov (United States)

    Majzoob, Sayeh; Atyabi, Fatemeh; Dorkoosh, Farid; Kafedjiiski, Krum; Loretz, Brigitta; Bernkop-Schnürch, Andreas

    2006-12-01

    This study was aimed at improving certain properties of pectin by introduction of thiol moieties on the polymer. Thiolated pectin was synthesized by covalent attachment of cysteine. Pectin-cysteine conjugate was evaluated for its ability to be degraded by pectinolytic enzyme. The toxicity profile of the thiolated polymer in Caco-2-cells, its permeation enhancing effect and its mucoadhesive and swelling properties were studied. Moreover insulin-loaded hydrogel beads of the new polymer were examined for their stability in simulated gastrointestinal conditions and their drug release profile. The new polymer displayed 892.27 +/- 68.68 micromol thiol groups immobilized per g polymer, and proved to have retained its biodegradability, upon addition of Pectinex Ultra SPL in-vitro, determined by viscosity measurements and titration method. Pectin-cysteine showed no severe toxicity in Caco-2 cells, as tested by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. Moreover, the synthesized polymer exhibited a relative permeation enhancement ratio of 1.61 for sodium fluorescein, compared to unmodified pectin. Pectin-cysteine conjugate exhibited approximately 5-fold increased in in-vitro adhesion duration and significantly improved cohesive properties. Zinc pectin-cysteine beads showed improved stability in simulated gastrointestinal media; however, insulin release from these beads followed the same profile as unmodified zinc pectinate beads. Due to favourable safety and biodegradability profile, and improved cohesive and permeation-enhancing properties, pectin-cysteine might be a promising excipient in various transmucosal drug delivery systems.

  3. Rheological properties and the mechanism of a viscous flow of aqueous pectin solutions

    Science.gov (United States)

    Netesova, G. A.; Kotov, V. V.; Bodyakina, I. M.; Lukin, A. L.

    2012-09-01

    The rheological properties and mechanisms of a viscous flow of diluted apple pectin solutions are investigated. It is found that the rise in solution viscosity upon an increase in concentration and a drop in temperature is, along with the corresponding degree to which the interaction between pectin molecules and solvent is reduced, associated with the processes of structuring. The entropy of a viscous flow of pectin solutions is found to be positive: it grows with a rise in concentration is virtually temperature independent. It is established that the entropy factor makes the main contribution to the free energy value of a viscous flow.

  4. Effects of Low-Ester Pectin on Wheat Dough's Physical Properties Detected by Rheological Method

    OpenAIRE

    Peilong Xu; Na Na; Qing Lin

    2013-01-01

    The study examined the influence of low-ester pectin on the rheological property of wheat dough through capillary rheological method. The experimental results showed that the more the content of low-ester pectin in wheat dough, the less viscosity of the dough, meanwhile, the higher of the dough strength, the weaker the maximum drawing force endured by the dough. Therefore, the content of low-ester pectin had a direct impact on gluten index of the dough, namely, the stability and stirring resi...

  5. Simultaneous ingestion of high-methoxy pectin from apple can enhance absorption of quercetin in human subjects.

    Science.gov (United States)

    Nishijima, Tomohiko; Takida, Yoshiki; Saito, Yasuo; Ikeda, Takayuki; Iwai, Kunihisa

    2015-05-28

    Chronic ingestion of apple pectin has been shown to increase the absorption of quercetin in rats. The present study was designed to elucidate whether the simultaneous ingestion of quercetin with apple pectin could enhance the absorption of quercetin in humans, and the effects of dose dependency and degree of pectin methylation on quercetin absorption were also investigated. Healthy volunteers (n 19) received 200 ml of 0.5 mg/ml of quercetin drinks with or without 10 mg/ml of pectin each in a randomised cross-over design study with over 1-week intervals; urine samples from all the subjects were collected within 24 h after ingestion of the test drinks, and urinary deconjugated quercetin and its metabolites were determined using HPLC. The sum of urinary quercetin and its metabolites excreted was increased by 2.5-fold by the simultaneous ingestion of pectin. The metabolism of methylated quercetin (isorhamnetin and tamarixetin) was not affected by pectin ingestion. In six volunteers, who received quercetin drinks containing 0, 3 and 10 mg/ml of pectin, the sum of urinary quercetin and its metabolites excreted also increased in a pectin dose-dependent manner. Furthermore, the simultaneous ingestion of quercetin with low-methoxy and high-methoxy pectin, respectively, increased the sum of urinary excretion of quercetin and its metabolites by 1.69-fold and significantly by 2.13-fold compared with the ingestion of quercetin without pectin. These results elucidated that apple pectin immediately enhanced quercetin absorption in human subjects, and that its enhancing effect was dependent on the dose and degree of pectin methylation. The results also suggested that the viscosity of pectin may play a role in the enhancement of quercetin absorption.

  6. Study of nanocomposites based on iron oxides and pectin

    Science.gov (United States)

    Chistyakova, Nataliya I.; Shapkin, Alexey A.; Sirazhdinov, Ruslan R.; Gubaidulina, Tatiana V.; Kiseleva, Tatiana Yu.; Kazakov, Alexander P.; Rusakov, Vyacheslav S.

    2014-10-01

    Mössbauer and X-ray diffraction study of nanocomposites based on iron oxides and pectin (PC) was carried out involving magnetization measurements. The concentrations of PC in nanocomposites varied from 0 to 10%. Mössbauer investigations of nanocomposites were carried out in the temperature range from 5 to 300 K. Many-state superparamagnetic relaxation model was used for spectra fitting. The magnetization, M(T,H), was measured in the temperature interval of 80-300 K and magnetic field up to 10 kOe. Formation of the "iron-polymer" interface was not observed. Particle sizes were estimated using the Mössbauer and X-ray powder diffraction data.

  7. Study of nanocomposites based on iron oxides and pectin

    Energy Technology Data Exchange (ETDEWEB)

    Chistyakova, Nataliya I., E-mail: nchistyakova@yandex.ru; Shapkin, Alexey A., E-mail: nchistyakova@yandex.ru; Sirazhdinov, Ruslan R., E-mail: nchistyakova@yandex.ru; Gubaidulina, Tatiana V., E-mail: nchistyakova@yandex.ru; Kiseleva, Tatiana Yu., E-mail: nchistyakova@yandex.ru; Kazakov, Alexander P., E-mail: nchistyakova@yandex.ru; Rusakov, Vyacheslav S., E-mail: nchistyakova@yandex.ru [M. V. Lomonosov Moscow State University, Faculty of Physics, Leninskie gory, 119991 Moscow (Russian Federation)

    2014-10-27

    Mössbauer and X-ray diffraction study of nanocomposites based on iron oxides and pectin (PC) was carried out involving magnetization measurements. The concentrations of PC in nanocomposites varied from 0 to 10%. Mössbauer investigations of nanocomposites were carried out in the temperature range from 5 to 300 K. Many-state superparamagnetic relaxation model was used for spectra fitting. The magnetization, M(T,H), was measured in the temperature interval of 80-300 K and magnetic field up to 10 kOe. Formation of the 'iron-polymer' interface was not observed. Particle sizes were estimated using the Mössbauer and X-ray powder diffraction data.

  8. Mechanistic aspects of the nucleophilic substitution of pectin. On the formation of chloromethane

    DEFF Research Database (Denmark)

    Sailaukhanuly, Yerbolat; Sárossy, Zsuzsa; Carlsen, Lars

    2014-01-01

    Chloromethane, accounting for approximately 16% of the tropospheric chlorine, is mainly coming from natural sources. However anthropogenic activities, such as combustion of biomass may contribute significantly as well. The present study focuses on the thermal solid state reaction between pectin, ...

  9. Optimization of the preparation of pectin from Aloe using a Box-Behnken design.

    Science.gov (United States)

    Geng, Lijing; Zhou, Wei; Qu, Xingyuan; Chen, Weijie; Li, Yingchang; Liu, Chang; Sun, Jing; Yu, Xiaolei; Wang, Hui; Zhang, Zhen; Li, Jing; Wang, Lijie

    2014-05-25

    The extraction condition of pectin from Aloe vera barbadensis Mill was optimized by a Box-Behnken design. The effect of parameters of extraction water proportion (EWP), extraction pH (EpH), extraction temperature (ETe), extraction time (ETi), alcohol precipitation pH (APpH)and alcohol precipitation temperature (APTe) on the extraction yield of pectin was investigated by a software of Design Export 8.0.5b. The maximum extraction yield was obtained with the EWP of 20:1, EpH of 1.5, ETe of 90°C, ETi of 120min, APpH of 3.0 and APTe of 50°C, which was consistent with the experimental value. We also found out that the pectin content decreased gradually during storage and sucrose concentration had a significant impact on the viscosity of pectin.

  10. Study on swelling behaviour of hydrogel based on acrylic acid and pectin from dragon fruit

    Science.gov (United States)

    Abdullah, Mohd Fadzlanor; Lazim, Azwani Mat

    2014-09-01

    Biocompatible hydrogel based on acrylic acid (AA) and pectin was synthesized using gamma irradiation technique. AA was grafted onto pectin backbone that was extracted from dragon fruit under pH 3.5 and extracts and ethanol ratios (ER) 1:0.5. The optimum hydrogel system with high swelling capacity was obtained by varying the dose of radiation and ratio of pectin:AA. FTIR-ATR spectroscopy was used to verify the interaction while thermal properties were analyzed by TGA and DSC. Swelling studies was carried out in aqueous solutions with different pH values as to determine the pH sensitivity. The results show that the hydrogel with a ratio of 2:3 (pectin:AA) and 30 kGy radiation dose has the highest swelling properties at pH of 10.

  11. Pectin functionalised by fatty acids: Diffuse reflectance infrared Fourier transform (DRIFT) spectroscopic characterisation

    Science.gov (United States)

    Kamnev, Alexander A.; Calce, Enrica; Tarantilis, Petros A.; Tugarova, Anna V.; De Luca, Stefania

    2015-01-01

    Chemically modified pectin derivatives obtained by partial esterification of its hydroxyl moieties with fatty acids (FA; oleic, linoleic and palmitic acids), as well as the initial apple peel pectin were comparatively characterised using diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. Characteristic changes observed in DRIFT spectra in going from pectin to its FA esters are related to the corresponding chemical modifications. Comparing the DRIFT spectra with some reported data on FTIR spectra of the same materials measured in KBr or NaCl matrices has revealed noticeable shifts of several polar functional groups both in pectin and in its FA-esterified products induced by the halide salts. The results obtained have implications for careful structural analyses of biopolymers with hydrophilic functional groups by means of different FTIR spectroscopic methodologies.

  12. Spatial frequency behavior of holograms made with pectin and oxidizing agents

    Science.gov (United States)

    Ordóñez-Padilla, M. J.; Olivares-Pérez, A.; Grijalva-Ortiz, N.; Fuentes-Tapia, I.

    2013-03-01

    Preparation of holographic gratings using photosensitive films pectin-H2O-oxidizing agent exposed to a He-Cd laser, wavelength of 442nm. For the photo-oxidation, we used two agents: ammonium dichromate and iron ammonium citrate. Parallel studies performed experimental variation of angles between overlapping beams that generate the interference pattern, generating different spatial frequencies in the holographic gratings. Were prepared from pectin-water-ammonium dichromate and pectin-water-ammoniacal iron citrate. Results module of the transfer function (MTF) of the materials used, to determine the diffraction efficiencies as a function of the spatial frequency (line/mm) of each holographic gratings, which were prepared with different pectin and oxidizing agents. We made an experimental analysis of the MTF, comparing each of the films with different photosensitizers applied.

  13. Application of Celluclast 1.5L in apple pectin extraction.

    Science.gov (United States)

    Wikiera, Agnieszka; Mika, Magdalena; Starzyńska-Janiszewska, Anna; Stodolak, Bożena

    2015-12-10

    Pectins were extracted from apple pomace with Celluclast 1.5L at a dose of 25, 50 and 75 μl per 1g of material. In obtained pectin, the galacturonic acid (GalA) content, the neutral sugars (NS) profile, the degree of methylation (DM) and acetylation (DAc), the molecular mass, protein, ash and polyphenol levels as well as antioxidant and antitumor activity were determined. The lowest dose of enzymatic preparation resulted in the yield of pectin isolation comparable with acidic treatment (15.3%). Application of higher dose caused further, almost 4% increase in polymer recovery. Enzymatically isolated pectin was characterised by larger molecular mass and contained more GalA of higher DM and DAc than polymer extracted with acid. It was also richer in protein and polyphenols, and had different NS profile, which resulted in higher antiradical activity as well as the ability to inhibit the proliferation and invasion of Caco-2 adenocarcinoma cells.

  14. Extraction, characterization and spontaneous emulsifying properties of pectin from sugar beet pulp.

    Science.gov (United States)

    Ma, Sen; Yu, Shu-juan; Zheng, Xue-ling; Wang, Xiao-xi; Bao, Qing-Dan; Guo, Xiao-ming

    2013-10-15

    The effects of organic acid extractants on the yield and characteristics of pectin from sugar beet pulp were investigated with citric acid, malic acid and lactic acid at different pH (1.5 and 2.0) and time (1 h and 2 h). The results demonstrated that the yields of pectins were directly correlated with the decrease of pH and reaction time, and the optimum yield of 17.2% was obtained at pH 1.5 and 2 h. Furthermore, the acid type also affected the physicochemical characteristics of pectin, especially on the esterification degree (42-71), galacturonic acid content (60.2-77.8%), emulsion activity (35.2-40.1%) and emulsion stability (62.1-79.4%), and a relatively single pectin mainly consisted of homogalacturonan could be obtained under a suitable reaction condition, which was an excellent crude material for the production of emulsion activity.

  15. 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

    2014-11-01

    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.

  16. 玉米细菌性茎腐病的发生为害调查%Surveys of the occurrence and damage of corn bacterial stalk rots (Erwinia chrysanthemi pv.zeae)

    Institute of Scientific and Technical Information of China (English)

    李巧芝; 高明; 王自伟; 高清珍; 罗秦岳

    2002-01-01

    系统调查表明,玉米细菌性茎腐病由玉米细菌性茎腐病菌 (Erwinia chrysanthemi pv.zeae)所致,在玉米植株中部叶鞘和茎秆上发生水渍状腐烂,引起组织软化.病菌随病残组织在田间、地边越冬.夏季暴雨多、空气湿度大、虫害发生重等对病害发生有利.提出及时清除病残体、防治虫害、适时施药的防治措施.

  17. An Endophytic Erwinia chrysanthemi Strain Antagonistic against Banana Fusarium Wilt Disease%一株对香蕉枯萎病菌具有良好拮抗作用的菊欧氏杆菌

    Institute of Scientific and Technical Information of China (English)

    殷晓敏; 陈弟; 吴红萍; 郑服丛

    2009-01-01

    在香蕉枯萎病重病园区,从生长正常香蕉假茎内分离获得一株细菌E353菌株.经对峙培养、孢子萌发抑制测定,E353对香蕉枯萎病菌菌丝生长、孢子萌发具有良好抑制效果.盆栽试验表明,E353活菌培养液(750ml/株)浸根处理,对香蕉枯萎病的防效为60.67%.经形态学、生理生化和16S rDNA序列比对,将E353鉴定为菊欧氏杆菌Erwinia chrysanthemi.

  18. Pathogenicity and Biological Characters of Erwinia chrysanthemi pv. zeae in Guangdong Province%广东水稻细菌性基腐病的致病性及生物学特性研究

    Institute of Scientific and Technical Information of China (English)

    刘琼光; 曾宪铭

    1999-01-01

    通过一系列的细菌学性状和致病性试验,鉴定出广东省水稻一种新病害--水稻细菌性基腐病的病原为菊欧氏杆菌玉米致病变种Erwinia chrysanthemi pv. zeae,并对该病原菌的生物学特性进行了进一步的研究.结果表明:病菌生长的最低温度为12 ℃,适宜温度范围28~36 ℃,其中以32 ℃最适,最高温度41 ℃,致死温度53 ℃、10 min.该病菌生长的pH值范围为pH 5~11,其中pH7最适宜.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Resistance identification of banana varieties to banana bacterial soft rot caused by Dickeya ( Pectobacterium chrysanthemi pv.paradisiaca )%香蕉品种对香蕉细菌性软腐病的抗性鉴定

    Institute of Scientific and Technical Information of China (English)

    蒲小明; 林壁润; 吕顺; 沈会芳; 周佳暖; 周建坤; 韩秀香

    2012-01-01

    Banana bacterial soft rot caused by Dickeya paradisiaca {Pectobacterium chrysanthemi pv. Paradisiaca) was a new devastating invasive disease in China, and using resistant varieties would be an effective method to control the disease. Detached leaf method and pot experiments were used to identify the resistance of 39 banana varieties. The results showed that the levels of resistance of these 39 banana varieties were different, among which 'Huangdi Banana' was highly resistant (HR), 'Red Dwarf' was resistant (R), and 'Aijiao Dundilei' and 'Long-zhou Zhongba' were moderately resistant (MR). Such method could identify resistant varieties effectively, rapidly and accurately, and the resistance results by detached leaf and pot experiments were consistent with those by the field experiments.%由菊欧文氏杆菌香蕉致病变种[Dickeya paradisiaca(原名Pectobacterium chrysanthemi pv.paradisiaca)]引起的香蕉细菌性软腐病是我国新入侵的毁灭性香蕉病害,应用抗病品种将是防治该病害的有效方法.采用离体叶片法和盆栽法相结合的筛选方法对39个香蕉品种进行抗性鉴定,结果表明,供试品种对香蕉细菌性软腐病菌的抗性存在明显差异,其中表现高抗(HR)的品种为‘皇帝蕉’,抗病(R)品种为‘红河矮’,中抗(MR)品种为‘矮脚遁地蕾’和‘龙州中把’.离体和盆栽鉴定结果与品种田间抗病性一致,可有效、快速、准确地筛选出抗病品种.

  1. Optimization of microwave assisted extraction of pectin from sour orange peel and its physicochemical properties.

    Science.gov (United States)

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

    2016-04-20

    Microwave assisted extraction technique was used to extract pectin from sour orange peel. Box-Behnken design was used to study the effect of irradiation time, microwave power and pH on the yield and degree of esterification (DE) of pectin. The results showed that the optimum conditions for the highest yield of pectin (29.1%) were obtained at pH of 1.50, microwave power of 700W, and irradiation time of 3min. DE values of pectin ranged from 1.7% to 37.5%, indicating that the obtained pectin was low in methoxyl. Under optimal conditions, the galacturonic acid content and emulsifying activity were 71.0±0.8% and 40.7%, respectively. In addition, the emulsion stability value ranged from 72.1% to 83.4%. Viscosity measurement revealed that the solutions of pectin at low concentrations showed nearly Newtonian flow behavior, and as the concentration increased, pseudoplastic flow became dominant.

  2. Sustainable production of pectin from lime peel by high hydrostatic pressure treatment.

    Science.gov (United States)

    Naghshineh, Mahsa; Olsen, Karsten; Georgiou, Constantinos A

    2013-01-15

    The application of high hydrostatic pressure technology for enzymatic extraction of pectin was evaluated. Cellulase and xylanase under five different combinations (cellulase/xylanase: 50/0, 50/25, 50/50, 25/50, and 0/50 U/g lime peel) at ambient pressure, 100 and 200 MPa were used to extract pectin from dried lime peel. Extraction yield, galacturonic acid (GalA) content, average molecular weight (M(w,ave)), intrinsic viscosity [η](w), and degree of esterification (DE) were compared to those parameters obtained for pectins extracted using acid and aqueous processes. Pressure level, type and concentration of enzyme significantly (ppectin. Enzyme and high pressure extraction resulted in yields which were significantly (pextraction. Although pressure-induced enzymatic treatment improves pectin yield, it does not have any significant effect on M(w,ave) and [η](w) of pectin extracts indicating the potential of high pressure treatment for enzymatic pectin production as a novel and sustainable process.

  3. Quanti-qualitative evaluation of pectins in the dietary fibre of 24 foods

    Directory of Open Access Journals (Sweden)

    Mario Bonsembiante

    2010-01-01

    Full Text Available The dietary fibre of 24 foods was analysed for its proportions of insoluble and soluble (SDF fractions and for its contentof high methoxyl pectins (HM, low methoxyl pectins (LM and protopectin. The fractional extraction and quantitativedetermination of pectins were performed on the total dietary fibre residue, following the procedure suggested byRobertson (1979. Total pectin content (TP, calculated as sum of the three fractions, ranged from 2.4 to 49.8 g/kg ofdry matter. The variation coefficient of TP measurements repeated on the same foods were, on average, 2%. Total pectincontent was 49.8 g/kg DM in dried beet pulp and averaged 33.8+_0.3 g/kg DM in fruits and vegetables, 13.2+_8.4 g/kgDM in legumes and tubers and only 2.8+_0.5 g/kg DM in cereals. HM fraction prevailed in apple and pear samples (>40%of TP, while LM and protopectin largely prevailed in legumes and vegetables. A strong variability among foods was foundfor the TP/SDF ratio. In general, within each food category, increasing levels of SDF were associated with decreasing valuesof TP/SDF ratio. Since many foods contain low amounts of pectins, care in the development of calibration curves forspectrophotometric reading is required. Finally, the whole procedure for pectin extraction and quantification on dietaryfibre of food is very complex and time-consuming.

  4. 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.

  5. Viscous-flow properties and viscosity-average molecular mass of orange peel pectin

    Institute of Scientific and Technical Information of China (English)

    周尽花; 吴宇雄; 沈志强

    2008-01-01

    The viscous-flow properties of pectin from the residue of orange peel after extraction of essential oil and flavonoid were studied and the viscosity-average molecular mass(Mv,ave) of this kind of pectin was determined.Experimental results show that Arrhenius viscous-flow equation can be applied to describing the effect of temperature on viscosity of this kind of orange peel pectin solutions with the average viscous-flow activation energy being 17.91 kJ/mol(depending on the concentration).Neither power equation,η =K1 cA1,nor exponential equation,η=K2exp(A2c) can describe the effect of concentration on viscosity of this kind of orange peel pectin solutions well.However,it seems that exponential equation model is more suitable to describe their relation due to its higher linear correlation coefficient.Schulz-Blaschke equation can be used to calculate the intrinsic viscosity of this kind of orange peel pectin.The Mv,ave of the orange peel pectin is 1.65×105 g/mol.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Characterization of pectins extracted from pomegranate peel and their gelling properties.

    Science.gov (United States)

    Abid, Mouna; Cheikhrouhou, S; Renard, Catherine M G C; Bureau, Sylvie; Cuvelier, Gérard; Attia, Hamadi; Ayadi, M A

    2017-01-15

    The composition of pomegranate peel, the main by-product during pomegranate processing, and some of the characteristics of the water-soluble pectins were investigated. Four tunisian pomegranate peels were subjected to hot aqueous extractions (86°C, 80min, 20mM nitric acid). Pomegranate peels yielded between 6.8% and 10.1% pectins. The extracted pectins were low methylated and were characterized by the predominance of homogalacturonan regions. Principal component analysis applied on FT-IR spectral data in the region between 4000 and 650cm(-1) differentiated the samples according to their degree of methylation. At pH 3, in the presence of 0.7% pectin, all solutions showed a rapid gel formation with G'>G″. With decreasing temperature from 90°C to 10°C, G' increased to reach a plateau at 10°C. The variation in the pectin gel formation between varieties was attributed to difference in pectin characteristics particularly the hydrodynamic volume and the neutral sugar content.

  8. Impact of hemicelluloses and pectin on sphere-like bacterial cellulose assembly

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Jin; Catchmark, Jeffrey M

    It has been shown previously that certain strains of the bacterium Gluconacetobacter xylinus produce a spherical form of cellulose where the cellulose was formed in a layered fashion. The spherical cellulose was used as a model system to study cellulose–hemicellulose and cellulose–pectin composite formation. Cultures were produced in the presence of 0.5% (w/v) xyloglucan, xylan, arabinogalactan and pectin under agitating conditions. Cellulose samples with xyloglucan and pectin had different macro structures compared to other culture conditions. The micro structures showed that these two samples formed dense cellulose layers and had fewer cellulose fiber connections between layers. Cellulose samples with xylan and xyloglucan were found to contain more Iβ cellulose as found in higher plants, and exhibited decreases in crystallinity and crystalline sizes according to X-ray diffraction patterns. IR spectroscopy confirmed the changes in crystal allomorph. Cellulose was also grown in cultures containing different blends of both xyloglucan and pectin. Results show that xyloglucan had the dominant impact on the assembly of cellulose, suggesting that xyloglucan and pectin may interact with cellulose at different points in the assembly process, or in different regions. Bacterial cellulose and biomass yields indicated that xyloglucan and pectin could also stimulate the growth of cellulose.

  9. Pectin-Lipid Self-Assembly: Influence on the Formation of Polyhydroxy Fatty Acids Nanoparticles

    Science.gov (United States)

    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. PMID:25915490

  10. Characterization and functional properties of mango peel pectin extracted by ultrasound assisted citric acid.

    Science.gov (United States)

    Wang, Miaomiao; Huang, Bohui; Fan, Chuanhui; Zhao, Kaili; Hu, Hao; Xu, Xiaoyun; Pan, Siyi; Liu, Fengxia

    2016-10-01

    Pectin was extracted from 'Tainong No. 1' mango peels, using a chelating agent-citric acid as extraction medium by ultrasound-assisted extraction (UAE) and conventional extraction (CE) at temperatures of 20 and 80°C. Chemical structures, rheological and emulsifying properties of mango peel pectins (MPPs) were comparatively studied with laboratory grade citrus pectin (CP). All MPPs exhibited higher protein content (4.74%-5.94%), degree of methoxylation (85.43-88.38%), average molecular weight (Mw, 378.4-2858kDa) than the CP, but lower galacuronic acid content (GalA, 52.21-53.35%). CE or UAE at 80°C resulted in significantly higher pectin yield than those at 20°C, while the extraction time for UAE-80°C (15min) was significantly shorter compared to CE-80°C (2h) with comparable pectin yield. Moreover, MPPs extracted at 80°C were observed with higher GalA and protein content, higher Mw, resulting in higher viscosity, better emulsifying capacity and stability, as compared to those extracted at 20°C and the CP. Therefore, these results suggested that MPPs from 'Tainong No. 1' may become a highly promising pectin with good thickening and emulsifying properties, using ultrasound-assisted citric acid as an efficient and eco-friendly extraction method.

  11. Small-angle X-ray scattering study on pectin-chitosan mixed solutions and thermoreversible gels.

    Science.gov (United States)

    Ventura, Irit; Bianco-Peled, Havazelet

    2015-06-01

    Hot solutions containing pectin and chitosan with pectin weight fraction of 0.75, in acidic pH, demonstrate gelation occurring upon cooling to room temperature. This study explores the origin of this gelation using small angle X-ray scattering (SAXS) as the main experimental tool. Modeling SAXS patterns revealed rigid rod conformation in chitosan solutions, whereas pectin formed a self-avoiding chain. In addition, nanometric aggregates were detected in pectin solutions. Pectin and chitosan in mixed solutions adopted a similar semiflexible conformation. The only sample that created a visually stable gel displayed a different pattern, characteristic to polymers gels. Manipulating the composition by adding urea and salts highlighted the important role of hydrogen bonding, which governs the gelation mechanism. Nevertheless, electrostatic interactions were also found to take part in the gelation. To the best of our knowledge, this is the first comprehensive and systematic SAXS study on these pectin-chitosan mixtures.

  12. Effect of pectin on adsorption of Cu(II) by two variable-charge soils from southern China.

    Science.gov (United States)

    Wang, Ru-hai; Zhu, Xiao-fang; Qian, Wei; Yu, Yuan-chun; Xu, Ren-kou

    2015-12-01

    The influence of pectin on Cu(II) adsorption by two variable-charge soils (an Oxisol and an Ultisol) was investigated. Pectin increased the adsorption, and the extent of adsorption increased linearly with the dose of pectin, being greater in the Oxisol than that in the Ultisol because the adsorption of pectin by the Oxisol was greater. Both Langmuir and Freundlich equations fitted the adsorption isotherms of Cu(II) for both soils well. The fitting parameters of both equations indicated that pectin increased not only the adsorption capacity of the soils for Cu(II) but also the adsorption strength of Cu(II). The effect of pectin decreased with rising pH in the pH range 3.5-6.0, although the extent of electrostatic adsorption of Cu(II) by both soils was markedly greater over the pH range. Fourier-transformed infrared spectroscopy analysis and zeta potential measurement of soil colloids indicated that adsorption of pectin by the soils made the negative charge on both soils more negative, which was responsible for the increase in the electrostatic adsorption of Cu(II) induced by the addition of pectin. In conclusion, pectin-enhanced adsorption of Cu(II) especially at low pH would be beneficial to the soils as it would decrease the activity and mobility of Cu(II) in acidic variable-charge soils.

  13. Protective role of pectin against cadmium-induced testicular toxicity and oxidative stress in rats.

    Science.gov (United States)

    Koriem, Khaled M M; Fathi, Gamal E; Salem, Huda A; Akram, Nabil H; Gamil, Sofie A

    2013-05-01

    Cadmium has been classified as an environmental pollutant and human carcinogen. Pectin is a family of complex polysaccharides that function as hydrating agents and cementing materials for the cellulosic network. The aim of this study was to evaluate the protective role of pectin against cadmium-induced testicular toxicity and oxidative stress in rats. Forty male Wistar rats were divided into five equal groups. Groups 1 and 2 were injected intraperitoneally (i.p.) saline (1 mg/kg) and pectin (50 mg/kg), respectively, two days/weeks over three weeks period. Groups 3-5 were injected i.p. with 1 mg/kg cadmium two days/week while groups 4 and 5 co-administrated i.p. with 25 and 50 mg/kg pectin, respectively, three days/week over three weeks period. The results of the present work revealed that cadmium-exposed rats showed decrease in serum testosterone, dehydroepiandrosterone sulfate and lactate dehydrogenase. Testicular cholesterol, total protein, glucose-6-phosphate dehydrogenase, 3β-hydroxysteroid dehydrogenase, superoxide dismutase, glutathione peroxidase, catalase, glutathione S-transferase and reduced glutathione levels were also decreased while testicular malondialdehyde level was increased after cadmium injection. On the other hand, serum luteinizing hormone, follicle stimulating hormone, sex hormone binding globulin and γ-glutamyl transpeptidase were increased after cadmium exposure. Cadmium also induced sperms loss. Co-administration of pectin with cadmium restores all the above parameters and sperms to the normal levels where pectin at higher dose was more effective than lower one. These results were supported by histochemical investigations. In conclusion, pectin can counteract the testicular toxicity and oxidative stress induced by cadmium and the effect was dose-dependent.

  14. 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

    2014-07-01

    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.

  15. Pectin May Hinder the Unfolding of Xyloglucan Chains during Cell Deformation: Implications of the Mechanical Performance of Arabidopsis Hypocotyls with Pectin Alterations

    Institute of Scientific and Technical Information of China (English)

    Willie Abasolo; Michaela Eder; Kazuchika Yamauchi; Nicolai Obel; Antje Reinecke; Lutz Neumetzler; John W.C. Dunlop; Gregory Mouille; Markus Pauly; Herman H(o)fte; Ingo Burgert

    2009-01-01

    Plant cell walls, like a multitude of other biological materials, are natural fiber-reinforced composite materials. Their mechanical properties are highly dependent on the interplay of the stiff fibrous phase and the soft matrix phase and on the matrix deformation itself. Using specific Arabidopsis thaliana mutants, we studied the mechanical role of the matrix assembly in primary cell walls of hypocotyls with altered xyloglucan and pectin composition. Standard microtensile tests and cyclic loading protocols were performed on rnurl hypocotyls with affected RGII borate diester cross-links and a hin-dered xyloglucan fucosylation as well as qua2 exhibiting 50% less homogalacturonan in comparison to wild-type. As a con-trol, wild-type plants (Col-0) and tour2 exhibiting a specific xyloglucan fucosylation and no differences in the pectin network were utilized. In the standard tensile tests, the ultimate stress levels (-tensile strength) of the hypocotyls of the mutants with pectin alterations (rnurl, qua2) were rather unaffected, whereas their tensile stiffness was noticeably reduced in comparison to Col-0. The cyclic loading tests indicated a stiffening of all hypocotyls after the first cycle and a plastic deformation during the first straining, the degree of which, however, was much higher for murl and qua2 hypo-cotyls. Based on the mechanical data and current cell wall models, it is assumed that folded xyloglucan chains between cellulose fibrils may tend to unfold during straining of the hypocotyls. This response is probably hindered by geometrical constraints due to pectin rigidity.

  16. CGR2 and CGR3 have critical overlapping roles in pectin methylesterification and plant growth in Arabidopsis thaliana.

    Science.gov (United States)

    Kim, Sang-Jin; Held, Michael A; Zemelis, Starla; Wilkerson, Curtis; Brandizzi, Federica

    2015-04-01

    Pectins are critical polysaccharides of the cell wall that are involved in key aspects of a plant's life, including cell-wall stiffness, cell-to-cell adhesion, and mechanical strength. Pectins undergo methylesterification, which affects their cellular roles. Pectin methyltransferases are believed to methylesterify pectins in the Golgi, but little is known about their identity. To date, there is only circumstantial evidence to support a role for QUASIMODO2 (QUA2)-like proteins and an unrelated plant-specific protein, cotton Golgi-related 3 (CGR3), in pectin methylesterification. To add to the knowledge of pectin biosynthesis, here we characterized a close homolog of CGR3, named CGR2, and evaluated the effect of loss-of-function mutants and over-expression lines of CGR2 and CGR3 in planta. Our results show that, similar to CGR3, CGR2 is a Golgi protein whose enzyme active site is located in the Golgi lumen where pectin methylesterification occurs. Through phenotypical analyses, we also established that simultaneous loss of CGR2 and CGR3 causes severe defects in plant growth and development, supporting critical but overlapping functional roles of these proteins. Qualitative and quantitative cell-wall analytical assays of the double knockout mutant demonstrated reduced levels of pectin methylesterification, coupled with decreased microsomal pectin methyltransferase activity. Conversely, CGR2 and CGR3 over-expression lines have markedly opposite phenotypes to the double knockout mutant, with increased cell-wall methylesterification levels and microsomal pectin methyltransferase activity. Based on these findings, we propose that CGR2 and CGR3 are critical proteins in plant growth and development that act redundantly in pectin methylesterification in the Golgi apparatus.

  17. New polyelectrolyte complex from pectin/chitosan and montmorillonite clay.

    Science.gov (United States)

    da Costa, Marcia Parente Melo; de Mello Ferreira, Ivana Lourenço; de Macedo Cruz, Mauricio Tavares

    2016-08-01

    A new nanocomposite hydrogel was prepared by forming a crosslinked hybrid polymer network based on chitosan and pectin in the presence of montmorillonite clay. The influence of clay concentration (0.5 and 2% wt) as well as polymer ratios (1:1, 1:2 and 2:1) was investigated carefully. The samples were characterized by different techniques: transmission and scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, swelling degree and compression test. Most samples presented swelling degree above 1000%, which permits characterizing them as superabsorbent material. Images obtained by transmission electron microscopy showed the presence of clay nanoparticles into hydrogel. The hydrogels' morphological properties were evaluated by scanning electron microscope in high and low-vacuum. The micrographs showed that the samples presented porous. The incorporation of clay produced hydrogels with differentiated morphology. Thermogravimetric analysis results revealed that the incorporation of clay in the samples provided greater thermal stability to the hydrogels. The compression resistance also increased with addition of clay.

  18. 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.

  19. Fat reduction in the formulation of frankfurter sausages using inulin and pectin

    Directory of Open Access Journals (Sweden)

    Gerardo Méndez-Zamora

    2015-03-01

    Full Text Available The aim of this study was to evaluate the influence of different concentrations of inulin and pectin as fat substitutes on the chemical composition, texture, and sensory acceptance of frankfurter sausages. Six treatments were evaluated to test fat replacement: control (T0; low fat control (T1; low fat with 15% inulin (T2; low fat with 30% inulin (T3; low fat with 7.5% inulin and 7.5% pectin (T4; and low fat with 15% inulin and 15% pectin (T5. The addition of fibers increased the yield (T3 and T5; 98.96%, and the color parameters were slightly reduced (T3. Moisture (61.14% and ashes (6.96% of sausages with inulin and pectin were higher (T5, while shear force, hardness, fracturability, gumminess, and chewiness (T3 and T5 were slightly lower than those of the control. The addition of inulin (T2 increased the sensory acceptance of the sausages (5.75. Fat can be replaced with inulin and pectin in frankfurter sausages to produce healthy and functional products.

  20. 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 (X1), microwave power (X2), pH (X3) and solid-to-liquid ratio (X4) on the extraction yield was examined. The optimum conditions of MAE were as follows: X1=2.15min; X2=517W; X3=2.26 and X4=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.

  1. Oxidized pectin cross-linked carboxymethyl chitosan: a new class of hydrogels.

    Science.gov (United States)

    Fan, Lihong; Sun, Yi; Xie, Weiguo; Zheng, Hua; Liu, Shuhua

    2012-01-01

    Oxidation of pectin was performed with sodium periodate to prepare pectin dialdehyde (PD). In this study we used the cross-linking reaction of the active aldehyde of PD and the amino of carboxymethyl chitosan (CMC) to prepare the hydrogels. By controlling the proportion of pectin dialdehyde and CMC we made different kinds of hydrogels. We systematically studied the characters of the hydrogels using Fourier transform infrared spectroscopy analysis of the pectin dialdehyde, CMC and the hydrogels, and also X-ray diffractometry and scanning electron microscopy analysis of the instrument of the hydrogels. Equilibrium swelling showed that the gels retained about 88-93% water. The water vapor transmission rate (WVTR) and the evaporation of water from gels showed that such hydrogels were optimal for maintaining a moist environment conducive for wound healing. Examination of the hemolytic potential showed that the hydrogels were nonhemolytic in nature. The hydrogels were non-toxic and blood-compatible. This hydrogel prepared from oxidized pectin and CMC without employing any extraneous cross-linking agents is expected to have potential as wound-dressing material.

  2. An investigation into the suitability of amidated pectin hydrogel beads as a delivery matrix for chloroquine.

    Science.gov (United States)

    Munjeri, O; Hodza, P; Osim, E E; Musabayane, C T

    1998-08-01

    The aim of the present study was to delay the release of chloroquine to distal parts of the gastrointestinal tract by using a multiparticulate hydrogel formulation. Amidated pectin chloroquine beads (PC) with varying pectin-to-chloroquine ratios (PC) w/w loadings of 4:1, 2:1, and 1:1 in the dried beads were prepared by the gelation of drug-loaded pectin solutions in the presence of calcium. In vitro release studies of chloroquine from pectin-chloroquine hydrogel beads and chloroquine diphosphate powder were carried out in simulated gastric and intestinal fluids. The total release of the entrapped chloroquine from the hydrogel beads was achieved between 4 and 7 h in simulated intestinal fluid, but total release was not achieved in simulated gastric fluid. However, total release from chloroquine diphosphate powder was achieved by 1.5 and 2 h in gastric and intestinal fluids, respectively. The plasma pharmacokinetics of chloroquine from pectin hydrogel beads and chloroquine diphosphate solution following single or repeated dosing were compared in male Sprague-Dawley rats over a period of 60 h. Oral administration of the hyrogel beads to rats produced maximum plasma concentrations by 7 h, but highest plasma concentrations following chloroquine solution administration were observed by 2 h. The dissolution data and appearance of significant plasma concentrations of chloroquine 2 to 4 h after oral administration suggests release in duodenum, jejunum, or ileum.

  3. Silk-pectin hydrogel with superior mechanical properties, biodegradability, and biocompatibility.

    Science.gov (United States)

    Numata, Keiji; Yamazaki, Shoya; Katashima, Takuya; Chuah, Jo-Ann; Naga, Naofumi; Sakai, Takamasa

    2014-06-01

    A new method is developed to prepare silk hydrogels and silk-pectin hydrogels via dialysis against methanol to obtain hydrogels with high concentrations of silk fibroin. The relationship between the mechanical and biological properties and the structure of the silk-pectin hydrogels is subsequently evaluated. The present results suggest that pectin associates with silk molecules when the silk concentration exceeds 15 wt%, suggesting that a silk concentration of over 15 wt% is critical to construct interacting silk-pectin networks. The silk-pectin hydrogel reported here is composed of a heterogeneous network, which is different from fiber-reinforced, interpenetrated networks and double-network hydrogels, as well as high-stiffness hydrogels (elastic modulus of 4.7 ± 0.9 MPa, elastic stress limit of 3.9 ± 0.1 MPa, and elastic strain limit of 48.4 ± 0.5%) with regard to biocompatibility and biodegradability.

  4. Endo-xylanase and endo-cellulase-assisted extraction of pectin from apple pomace.

    Science.gov (United States)

    Wikiera, Agnieszka; Mika, Magdalena; Starzyńska-Janiszewska, Anna; Stodolak, Bożena

    2016-05-20

    Pectins were extracted from apple pomace with monoactive preparation of endo-xylanase and endo-cellulase. The process was conducted for 10 h in conditions of pH 5.0 at 40 °C, with constant shaking. Endo-xylanase application resulted in the highest extraction efficiency of pectins (19.8%). The obtained polymer was characterised by a very high molecular mass, high level of neutral sugars - mainly arabinose, galactose and glucose, and very high DM (73.4). It also contained the highest level of protein and phenols. Pectin extracted with endo-cellulase had 1.5 fold lower molecular mass but contained significantly more GalA (70.5%) of a high degree of methylation (66.3%). The simultaneous application of both enzymatic preparations resulted in their cooperation, leading to a decrease of both the extraction efficiency and the molecular mass of pectin. However, this pectin was distinguished by the highest GalA (74.7%) and rhamnose contents.

  5. 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.

  6. 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.

  7. Effect of pectin particles and cotton fibers on properties of thermoplastic cassava starch composites

    Directory of Open Access Journals (Sweden)

    Jutarat Prachayawarakorn

    2016-04-01

    Full Text Available Due to poor mechanical properties and high water uptake of thermoplastic starch (TPS, this research focused on property improvement of thermoplastic cassava starch (TPCS using natural compatible polymers, i.e. pectin particles and cotton fibers. Different TPCS composites, reinforced by the pectin particles and/or the cotton fibers, were compounded and shaped using an internal mixer and a compression molding machine, respectively. It was found from infrared (IR spectra that the peak position of O-H stretching of the TPCS polymer clearly shifted to lower wavenumber by the addition of the pectin particles and/or the cotton fibers. Moreover, the significant increase of stress at maximum load and Young’s modulus of the TPCS/pectin particle and the TPCS/cotton fiber composites was observed. The drop of water uptake was also found when the cotton fibers were incorporated into the TPCS matrix with/without pectin particles. In addition, X-Ray Diffraction, Scanning Electron Microscopy and Thermogravimetric Analysis were used to characterize different TPCS composites.

  8. 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.

  9. Double emulsions stabilized by a charged complex of modified pectin and whey protein isolate.

    Science.gov (United States)

    Lutz, Rachel; Aserin, Abraham; Wicker, Louis; Garti, Nissim

    2009-08-01

    Double emulsions based on naturally occurring stabilizers for food applications were studied. Two charged biopolymers, whey protein isolate (WPI) and enzymatic modified pectins, interacted in aqueous solution to form a charge-charge complex that was utilized as a hydrophilic polymeric steric stabilizer improving the double emulsion stability. The main factors that influence the interaction between protein and pectin were investigated in relation to double emulsion stability: creaming, coalescence, and water transport between aqueous phases. The pH determined the size of the complex formed. Thus at pH 6, where a soluble complex was obtained between some molecular positively charged patches on the protein and negatively charged fractions of the hydrocolloids, the double emulsion was the most stable. With the smallest droplet size (ca. 15 microm), the lowest creaming, highest yield, and minimized water transport were obtained. The best concentration and ratio to form the soluble complex are 4 wt% WPI and 0.5 wt% pectin (for 30 wt% of the W/O inner phase). The influence of the charge distribution (degree of order of the carboxylic groups) of the pectin on the associated complex was also investigated, and it was found that the more "ordered" pectin (U63) formed the most stable double emulsion against water transport.

  10. 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.

  11. Effects of dietary pectin and fat on the small intestinal contents and exocrine pancreas of rats.

    Science.gov (United States)

    Forman, L P; Schneeman, B O

    1980-10-01

    The effects of dietary pectin and fat level on digestive enzyme activities in the pancreas and small intestine and on intestinal bile acid levels were investigated. In unfed rats, dietary pectin did not influence the pancreatic enzymes studied, but a higher level of corn oil in the diet lowered the amylase activity in the pancreas, increased pancreatic lipase activity and slightly lowered the chymotrypsin and trypsin activities. Diet did not change the dry weight of the pancreas. In the fed rats, dietary pectin increased the dry weight of the small gut wash plus the mucosal scraping. Dietary pectin increased the small intestinal lipase and chymotrypsin levels and at the low level of fat only, increased amylase and trypsin activities in the small intestine of fed rats. Intestinal lipase levels were higher and amylase levels lower in rats consuming the high level of corn oil. These results indicate that changes in dietary fat level led to changes in the amylase and lipase content of secreted pancreatic juice and that differences in absorption associated with diets containing pectin could be the result of increased material in the small intestine.

  12. Polyamines as new cationic plasticizers for pectin-based edible films.

    Science.gov (United States)

    Esposito, Marilena; Di Pierro, Prospero; Regalado-Gonzales, Carlos; Mariniello, Loredana; Giosafatto, C Valeria L; Porta, Raffaele

    2016-11-20

    Zeta potential and particle size were determined on pectin aqueous solutions as a function of pH and the effects of calcium ions, putrescine and spermidine on pectin film forming solutions and derived films were studied. Ca(2+) and polyamines were found to differently influence pectin zeta potential as well as thickness and mechanical and barrier properties of pectin films prepared at pH 7.5 either in the presence or absence of the plasticizer glycerol. In particular, Ca(2+) was found to increase film tensile strength and elongation at break only in the presence of glycerol and did not affect film thickness and permeability to both water vapor and CO2. Conversely, increasing polyamine concentrations progressively reduced film tensile strength and markedly enhanced film thickness, elongation at break and permeability to water vapor and CO2, both in the presence and absence of glycerol. Our findings indicate that polyamines give rise to a structural organization of the heteropolysaccharide different from that determined by calcium ions, previously described as "egg box" model, and suggest their possible application as plasticizers to produce pectin-based "bioplastics" with different features.

  13. Preparation and biocompatibility evaluation of pectin and chitosan cryogels for biomedical application.

    Science.gov (United States)

    Konovalova, Mariya V; Markov, Pavel A; Durnev, Eugene A; Kurek, Denis V; Popov, Sergey V; Varlamov, Valery P

    2017-02-01

    Today, there is a need for the development of biomaterials with novel properties for biomedical purposes. The biocompatibility of materials is a key factor in determining its possible use in biomedicine. In this study, composite cryogels were obtained based on pectin and chitosan using ionic cryotropic gelation. For cryogel preparation, apple pectin (AP), Heracleum L. pectin (HP), and chitosan samples with different physical and chemical characteristics were used. The properties of pectin-chitosan cryogels were found to depend on the structural features and physicochemical characteristics of the pectin and chitosan within them. The addition of chitosan to cryogels can increase their mechanical strength, cause change in surface morphology, increase the degradation time, and enhance adhesion to biological tissues. Cryogels based on AP were less immunogenic when compared with cryogels from HP. Cryogels based on AP and HP were hemocompatible and the percentage of red blood cells hemolysis was less than 5%. Unlike cryogels based on HP, which exhibited moderate cytotoxicity, cryogels based on AP exhibited light cytotoxicity. Based on the results of low immunogenicity, light cytotoxicity data as well as a low level of hemolysis of composite cryogels based on AP and chitosan are biocompatible and can potentially be used in biomedicine. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 547-556, 2017.

  14. 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.

  15. Effect of dietary high- and low-methylated citrus pectin on the activity of the ileal microflora and morphology of the small intestinal wall of broiler chicks

    NARCIS (Netherlands)

    Langhout, D.J.; Schutte, J.B.; Leeuwen, P. van; Wiebenga, J.; Tamminga, S.

    1999-01-01

    1. A study was conducted with broiler chicks to evaluate the effects of dietary high-methylated citrus pectin (HMC) or low-methylated citrus pectin (LMC) on the performance, nutrient digestibility, morphology of the small intestinal wall and ileal microbial activity. 2. Both pectin products were tes

  16. Alkali-Soluble Pectin Is the Primary Target of Aluminum Immobilization in Root Border Cells of Pea (Pisum sativum).

    Science.gov (United States)

    Yang, Jin; Qu, Mei; Fang, Jing; Shen, Ren Fang; Feng, Ying Ming; Liu, Jia You; Bian, Jian Feng; Wu, Li Shu; He, Yong Ming; Yu, Min

    2016-01-01

    We investigated the hypothesis that a discrepancy of Al binding in cell wall constituents determines Al mobility in root border cells (RBCs) of pea (Pisum sativum), which provides protection for RBCs and root apices under Al toxicity. Plants of pea (P. sativum L. 'Zhongwan no. 6') were subjected to Al treatments under mist culture. The concentration of Al in RBCs was much higher than that in the root apex. The Al content in RBCs surrounding one root apex (10(4) RBCs) was approximately 24.5% of the total Al in the root apex (0-2.5 mm), indicating a shielding role of RBCs for the root apex under Al toxicity. Cell wall analysis showed that Al accumulated predominantly in alkali-soluble pectin (pectin 2) of RBCs. This could be attributed to a significant increase of uronic acids under Al toxicity, higher capacity of Al adsorption in pectin 2 [5.3-fold higher than that of chelate-soluble pectin (pectin 1)], and lower ratio of Al desorption from pectin 2 (8.5%) compared with pectin 1 (68.5%). These results indicate that pectin 2 is the primary target of Al immobilization in RBCs of pea, which impairs Al access to the intracellular space of RBCs and mobility to root apices, and therefore protects root apices and RBCs from Al toxicity.

  17. Effects of calcium pH, and blockiness on kinetic rheological behaviour and microstructure of HM pectin gels

    NARCIS (Netherlands)

    Lofgren, C.; Guillotin, S.E.; Evenbratt, E.; Schols, H.A.; Hermansson, A.M.

    2005-01-01

    The kinetic behavior during gel formation and the microstructure of 0.75% high methoxyl (HM) pectin gels in 60% sucrose have been investigated by oscillatory measurements and transmission electron microscopy for three comparable citrus pectin samples differing in their degree of blockiness (DB). Ca2

  18. The preparation of polyelectrolyte complexes carboxymethyl chitosan(CMC)-pectin by reflux method as a Pb (II) metal ion adsorbent

    Science.gov (United States)

    Hastuti, Budi; Mudasir, Siswanta, Dwi; Triyono

    2016-02-01

    Aim of this research is to synthesized a chemically stable polyelectrolyte complexs carboxymetyl chitosan CMC-pectin as Pb(II) ion adsorbent by reflux method. During synthesis process, the optimum mass ratio of CMC and pectin was pre-determined and the active groups of the CMC-pectin complex was characterized by using IR spectrofotometer. Finally, adsorption capacity of the adsorbent material for Pb (II) ions was studied under optimum condition, i.e. adsorbent mass, contact time, and pH. Result shows that CMC could be succesfully combined with pectin to produce CMC-pectin complex. The optimum mass ratio CMC: pectin to form the polyelectrolyte complexs CMC-pectin was 70% : 30%. The active groups identified in the CMC-pectin complex was a hydroxyl (OH) and carboxylate (-COOH) groups. The optimum conditions for Pb (II) ion absoprtion was 10 mg of the adsorbent mass, 75 min of contact time, and pH 5. This material can be effectively used as adsorbents for Pb (II) ions, where up to 91% Pb (II) metal ions was adsorbed from aqueous solution and the adsorption capacity of the adsorbent was 41.63 mg/g.

  19. Alkali-Soluble Pectin Is the Primary Target of Aluminum Immobilization in Root Border Cells of Pea (Pisum sativum)

    Science.gov (United States)

    Yang, Jin; Qu, Mei; Fang, Jing; Shen, Ren Fang; Feng, Ying Ming; Liu, Jia You; Bian, Jian Feng; Wu, Li Shu; He, Yong Ming; Yu, Min

    2016-01-01

    We investigated the hypothesis that a discrepancy of Al binding in cell wall constituents determines Al mobility in root border cells (RBCs) of pea (Pisum sativum), which provides protection for RBCs and root apices under Al toxicity. Plants of pea (P. sativum L. ‘Zhongwan no. 6’) were subjected to Al treatments under mist culture. The concentration of Al in RBCs was much higher than that in the root apex. The Al content in RBCs surrounding one root apex (104 RBCs) was approximately 24.5% of the total Al in the root apex (0–2.5 mm), indicating a shielding role of RBCs for the root apex under Al toxicity. Cell wall analysis showed that Al accumulated predominantly in alkali-soluble pectin (pectin 2) of RBCs. This could be attributed to a significant increase of uronic acids under Al toxicity, higher capacity of Al adsorption in pectin 2 [5.3-fold higher than that of chelate-soluble pectin (pectin 1)], and lower ratio of Al desorption from pectin 2 (8.5%) compared with pectin 1 (68.5%). These results indicate that pectin 2 is the primary target of Al immobilization in RBCs of pea, which impairs Al access to the intracellular space of RBCs and mobility to root apices, and therefore protects root apices and RBCs from Al toxicity. PMID:27679639

  20. Covalent TiO(2)/pectin microspheres with Fe(3)O(4) nanoparticles for magnetic field-modulated drug delivery.

    Science.gov (United States)

    da Silva, Elisangela P; Sitta, Danielly L A; Fragal, Vanessa H; Cellet, Thelma S P; Mauricio, Marcos R; Garcia, Francielle P; Nakamura, Celso V; Guilherme, Marcos R; Rubira, Adley F; Kunita, Marcos H

    2014-06-01

    Covalent TiO(2)-co-pectin microspheres containing Fe(3)O(4) nanoparticles were developed through an ultrasound-induced crosslinking/polymerization reaction between the glycidyl methacrylate from vinyl groups in TiO(2) and in pectin. ζ-potentials became less negative in the nanostructured microspheres, caused by the presence of both inorganic particles in the negatively charged pectin. The nanostructured pectin microspheres showed an amoxicillin release rate slower than that of pure pectin microspheres. The proposed microspheres were found to be a sustained release system of amoxicillin in the acid medium. Furthermore, the antibiotic release may be modulated by exposition of the microspheres to a remote magnetic field. In practical terms, the nanostructured microspheres could deliver a larger proportion of their initial load to specific site of action. The cytotoxic concentrations for 50% of VERO cells (CC(50)), calculated as the concentration required to reduce cell viability by 50% after 72h of incubation, for pectin-only microspheres and nanostructured pectin microspheres were 217.7±6.5 and 121.5±4.9μgmL(-1), respectively. The obtained CC(50) values indicated acceptable cytotoxic levels for an incubation period of 72h, showing that the pectin microspheres have a great pharmacological potential for uses in biological environments, even after the introduction of both Fe(3)O(4) and TiO(2).

  1. Reducing the content of carrier polymer in pectin nanofibers by electrospinning at low loading followed with selective washing.

    Science.gov (United States)

    Cui, Sisi; Yao, Bing; Sun, Xue; Hu, Junli; Zhou, Yifa; Liu, Yichun

    2016-02-01

    Nanofibers of natural polymers represent an essential class of materials in biomedicine. Pectin is a plant-sourced anionic polysaccharide widely used in food products and biomedicine owning to its abundance, biocompatibility and inherent bioactivity. However, current electrospun pectin nanofibers are suffered from high content of carrier polymer, which may lead to low integrity and mechanical strength as well as in vivo toxicity. We report here a strategy to reduce the content of carrier polymer, polyethylene oxide (PEO) in our study, in pectin nanofibers, via electrospinning at low loading followed with selective washing. With improved electrospinning condition, we first enabled electrospinning of pectin nanofibers at low PEO loading. Then the PEO was removed by washing with a selective solvent to give pectin nanofibers containing only 1.5% PEO. The strategy was versatile to pectins from various sources and of various degree of esterification. The pectin nanofibers exhibited Young's modulus as high as 358.5MPa. In view of their rich bioactivity, the pectin nanofibers of low content of carrier polymer are promising materials for a wide range of biomedical applications.

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

    2017-01-01

    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 e

  3. 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

    2017-01-01

    SCOPE: We aimed to investigate the effects of three different soluble pectins on the digestion of other carbohydrates consumed, 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 enri

  4. Identification of amino acid residues critical for catalysis and stability in Aspergillus niger family 1 pectin lyase A

    NARCIS (Netherlands)

    Sanchez-Torres, P.; Visser, J.; Benen, J.A.E.

    2003-01-01

    Site-directed-mutagenesis studies were performed on family 1 pectin lyase A (PL1A) from Aspergillus niger to gain insight into the reaction mechanism for the pectin lyase-catalysed beta-elimination cleavage of methylesterified polygalacturonic acid and to stabilize the enzyme at slightly basic pH. O

  5. A kinetic study of a poorly water soluble drug released from pectin microcapsules using diffusion/dissolution model

    Science.gov (United States)

    A new microcapsular system for controlled drug delivery was developed from pectins obtained from various sources, with different molecular weight and degree of esterification. The release kinetics of a poorly water-soluble drug from the pectin microcapsules was investigated in simulated gastrointes...

  6. Physicochemical and functional performance of pectin extracted by QbD approach from Tamarindus indica L. pulp.

    Science.gov (United States)

    Sharma, Radhika; Kamboj, Sunil; Khurana, Rajneet; Singh, Gursharan; Rana, Vikas

    2015-12-10

    The aim of present investigation was to utilize quality by design (QbD) approach for extraction of tamarind pectin (TP) from Tamarindus indica L. pulp employing purity descriptors as indicator. The software generated quadratic equations showed significant effect of polarity index as compared to pulp concentration and boiling temperature on percentage yield and purity characteristics of TP. An insignificant effect on purity descriptors and percentage yield of TP upon replacement of acetone with methanol during predicted vs observed correlation studies (being similar polarity index of 5.1) pointed towards overwhelming influence of solvent polarity. Further, the FTIR-ATR, (1)H NMR, DSC and mass spectroscopy suggested TP was rhamnogalacturonan pectin with no tartaric acid content. TP was found to have significantly higher antioxidant activity as compare to apple pomace pectin, citrus peel pectin and commercial pectin. Overall, the physicochemical properties and antioxidant potential of TP could be utilized as an excipient for food and pharmaceutical industry.

  7. Application of D-optimal design to extract the pectin from lime bagasse using microwave green irradiation.

    Science.gov (United States)

    Thirugnanasambandham, K; Sivakumar, V

    2015-01-01

    The main objective of the present study is to extract the pectin from lime bagasse under various extraction conditions such as microwave power, extraction time, temperature, pH and mass of the sample. RSM coupled with D-optimal experimental design was used to optimize and investigate the extraction conditions on the pectin yield. Second order polynomial equation was developed and its adequacy was analyzed by analysis of variance (ANOVA). The optimal extraction was found to be as follows; microwave power of 400 W, extraction time of 500 s, temperature of 30 °C, pH of 1 and mass of the sample of 6g. Under these optimal scheme, 7.8 g/100g of pectin was extracted. Molecular weight of the pectin polymer and the distribution of the pectin compounds were determined by gel filtration chromatography.

  8. 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 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.

  9. Combined rheological and ultrasonic study of alginate and pectin gels near the sol-gel transition.

    Science.gov (United States)

    Audebrand, Michel; Kolb, Max; Axelos, Monique A V

    2006-10-01

    The sol-gel transition of biopolymer mixtures has been investigated by rheological and ultrasonic measurements. A scaling analysis of the data was performed for both types of measurements. A gel time was determined from rheology for the pure pectin samples, and the data could be fitted to a universal scaling form near the transition point. Its critical exponents are in good agreement with the predictions of scalar percolation theory. In addition, the ultrasonic signal of the pectin samples close to the transition was analyzed in terms of a high-frequency scaling approach for the attenuation and the velocity. For the alginate samples and the mixtures, for which the gel point cannot be determined reliably from rheology, the ultrasonic measurements were analyzed using the same scaling form as for the pectin sample, thus providing a method for estimating the gel point, even in the absence of rheological data.

  10. External and internal gelation of pectin solutions: microscopic dynamics versus macroscopic rheology

    Science.gov (United States)

    Secchi, E.; Munarin, F.; Alaimo, M. D.; Bosisio, S.; Buzzaccaro, S.; Ciccarella, G.; Vergaro, V.; Petrini, P.; Piazza, R.

    2014-11-01

    Pectin is a natural biopolymer that forms, in the presence of divalent cations, ionic-bound gels typifying a large class of biological gels stabilized by non-covalent cross-links. We investigate and compare the kinetics of formation and aging of pectin gels obtained either through external gelation via perfusion of free Ca2+ ions, or by internal gelation due to the supply of the same ions from the dissolution of CaCO3 nanoparticles. The microscopic dynamics obtained with photon correlation imaging, a novel optical technique that allows obtaining the microscopic dynamics of the sample while retaining the spatial resolution of imaging techniques, is contrasted with macroscopic rheological measurements at constant strain. Pectin gelation is found to display peculiar two-stage kinetics, highlighted by non-monotonic growth in time of both microscopic correlations and gel mechanical strength. These results are compared to those found for alginate, another biopolymer extensively used in food formulation.

  11. External and internal gelation of pectin solutions: microscopic dynamics versus macroscopic rheology.

    Science.gov (United States)

    Secchi, E; Munarin, F; Alaimo, M D; Bosisio, S; Buzzaccaro, S; Ciccarella, G; Vergaro, V; Petrini, P; Piazza, R

    2014-11-19

    Pectin is a natural biopolymer that forms, in the presence of divalent cations, ionic-bound gels typifying a large class of biological gels stabilized by non-covalent cross-links. We investigate and compare the kinetics of formation and aging of pectin gels obtained either through external gelation via perfusion of free Ca(2+) ions, or by internal gelation due to the supply of the same ions from the dissolution of CaCO3 nanoparticles. The microscopic dynamics obtained with photon correlation imaging, a novel optical technique that allows obtaining the microscopic dynamics of the sample while retaining the spatial resolution of imaging techniques, is contrasted with macroscopic rheological measurements at constant strain. Pectin gelation is found to display peculiar two-stage kinetics, highlighted by non-monotonic growth in time of both microscopic correlations and gel mechanical strength. These results are compared to those found for alginate, another biopolymer extensively used in food formulation.

  12. A Miniature Membrane Reactor for Evaluation of Process Design Options on the Enzymatic Degradation of Pectin

    DEFF Research Database (Denmark)

    Zainal Alam, Muhd Nazrul Hisham; Pinelo, Manuel; Arnous, Anis

    2011-01-01

    The objective of this paper is to assess if a membrane microbioreactor system could potentially be used to diagnose consequences of different process design and reactor operation options relevant for larger-scale enzymatic degradation of pectin reactions. The membrane microbioreactor prototype...... was demonstrated by performing a continuous enzymatic degradation of pectin experiment for a range of reactor conditions: different membrane molecular weight cutoff (MWCO) values, enzyme-to-substrate ratios (E/S), and substrate feeding rates (F) were assessed. Based on the experimental data, it was found...... design affected the membrane rejection profile. The results obtained thus underlined the suitability of a miniature membrane reactor system for evaluating different process design options that are relevant for larger-scale reactions of enzymatic pectin degradation....

  13. Preparation and characterization of amidated pectin based hydrogels for drug delivery system.

    Science.gov (United States)

    Mishra, R K; Datt, M; Pal, K; Banthia, A K

    2008-06-01

    In the current studies attempts were made to prepare hydrogels by chemical modification of pectin with ethanolamine (EA) in different proportions. Chemically modified pectin products were crosslinked with glutaraldehyde reagent for preparing hydrogels. The hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR), organic elemental analysis, X-ray diffraction studies (XRD), swelling studies, biocompatibility and hemocompatibility studies. Mechanical properties of the prepared hydrogels were evaluated by tensile test. The hydrogels were loaded with salicylic acid (used as a model drug) and drug release studies were done in a modified Franz's diffusion cell. FTIR spectroscopy indicated the presence of primary and secondary amide absorption bands. XRD studies indicated increase in crystallinity in the hydrogels as compared to unmodified pectin. The degree of amidation (DA) and molar and mass reaction yields (YM and YN) was calculated based on the results of organic elemental analysis. The hydrogels showed good water holding properties and were found to be compatible with B-16 melanoma cells & human blood.

  14. Sodium hydroxide-mediated hydrogel of citrus pectin for preparation of fluorescent carbon dots for bioimaging.

    Science.gov (United States)

    Zhao, Xi Juan; Zhang, Wen Lin; Zhou, Zhi Qin

    2014-11-01

    The citrus process industry produces annually a huge amount of pomace, which is a rich source of citrus pectin. Here, we report the hydrogel of citrus pectin mediated by sodium hydroxide can be used to prepare fluorescent carbon dots (CDs). The introduction of hydrogel can not only make the temperature of the hydrothermal reaction down to 100 °C, but also avoid visually carbonized precipitates in the synthesis process even up to 180 °C. The as-synthesized CDs are well dispersed in water with an average size of 2.7 nm and show cyan fluorescence with high photostability, good biocompatibility. Furthermore, the CDs can act as a potential fluorescent probe for cell imaging. Citrus pectin as a non-toxic carbonaceous precursor for preparation of fluorescent CDs provides a new approach for the efficient utilization of citrus germplasm in future.

  15. Application of ionic liquids in the microwave-assisted extraction of pectin from lemon peels.

    Science.gov (United States)

    Guolin, Huang; Jeffrey, Shi; Kai, Zhang; Xiaolan, Huang

    2012-01-01

    Microwave-assisted extraction of pectin from lemon peels by using ionic liquid as alternative solvent was investigated. The extracted pectin was detected by Fourier transform infrared spectra. The extraction conditions were optimized through the different experiments in conjunction with the response surface methodology. A pectin yield of 24.68 % was obtained under the optimal parameters: the extraction temperature of 88°C, the extraction time of 9.6 min, and a liquid-solid ratio of 22.7 ml · g(-1). The structure of the pretreated lemon peel samples and the samples after microwave-assisted extraction were characterized by a field emission scanning electron microscope.

  16. Physicochemical Properties of Pectin from Retama raetam Obtained using Sequential Extraction

    Science.gov (United States)

    Kacem, I.; Majdoub, H.; Roudesli, S.

    Water-soluble polysaccharides were extracted sequentially from Retama raetam. Dried Alcohol-Insoluble Residues (AIR) of Retama raetam were treated sequentially with deionised water, ammonium oxalate and basic solutions and purified by ultrafiltration. The resulting pectin extracts analysed for some physicochemical parameters. The results show that pectin yield (62% dry AIR), uronic acid (260-640 mg g-1), neutral sugars (320-540 mg g-1), degree of methylation (20-31%) and acetylation (2-19%), molar mass (8. 93x104-3.42x105 g mol-1) and intrinsic viscosity (27- 47 mL g-1) varied with the various extraction methods used. Extraction with ammonium oxalate solution gave the highest pectin yield, with high molar mass and degree of methylation.

  17. Microwave assisted extraction of pectin from waste Citrullus lanatus fruit rinds.

    Science.gov (United States)

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

    2014-01-30

    In this present study, microwave-assisted extraction (MAE) was applied to extraction of pectin from waste Citrullus Lanatus fruit rinds. Extraction parameters which are employed in this study are microwave power (160-480 W), irradiation time (60-180s), pH (1-2) and solid-liquid ratio (1:10-1: 30 g/ml) and they were optimized using a four factor three levels Box-Behnken response surface design (BBD) coupled with desirability function methodology. The results showed that, all the process variables have significant effect on the extraction yield of pectin. Optimum MAE conditions for the highest pectin yield from waste C. Lanatus fruit rinds (25.79%) were obtained with microwave power of 477 W, irradiation time of 128 s, pH of 1.52, solid-liquid ratio of 1:20.3g/ml respectively. Validation experiment results were well agreed with predicted value.

  18. Process variables influence on microwave assisted extraction of pectin from waste Carcia papaya L. peel.

    Science.gov (United States)

    Maran, J Prakash; Prakash, K Arun

    2015-02-01

    The objectives of the present study were to evaluate and optimize the influence of process variables such as microwave power, pH, time and solid-liquid ratio on the extraction of pectin from waste Carcia papaya L peel. The experiments were carried out based on a four factors three level Box-Behnken response surface design. A quadratic model was developed from the experimental data in order to predict the pectin yield. The optimal condition was found to be: microwave power of 512 w, pH of 1.8, time of 140 s and solid-liquid ratio of 1:15 g/ml with maximum pectin yield (25.41%).

  19. Extraction of pectin from Premna microphylla turcz leaves and its physicochemical properties.

    Science.gov (United States)

    Chen, Jun; Liang, Rui-hong; Liu, Wei; Luo, Shun-jing; Liu, Cheng-mei; Wu, Shuang-shuang; Wang, Zhao-jun

    2014-02-15

    Premna microphylla turcz leaves (PMTL) have been used for preparing a "green tofu" by Chinese for a long history. Chemical composition analysis indicated alcohol insoluble solids (AIS) of PMTL contained high amount of pectin. Water, ammonium oxalate, hydrochloric acid and sodium hydroxide were used to extract different pectic fractions sequentially. Ammonium oxalate was found to be the most effective extracting agent, reflecting on a high yield (20.61%) and a significant change of morphology of AIS. The resulted oxalate-soluble pectin (OXSP) showed high galacturonic acid content (76.15%) and average molecular weight (980.67kDa), low neutral sugar content (6.41%) and degree of methoxylation (14.90%). All of the characteristics have contributed excellent gelling and thickening properties of OXSP. These results may allow an improved use of PMTL as a resource of low-methoxyl pectin, and observation of the morphology of residues can be helpful for evaluating the efficiency of extracting agents.

  20. Application of Ionic Liquids in the Microwave-Assisted Extraction of Pectin from Lemon Peels

    Directory of Open Access Journals (Sweden)

    Huang Guolin

    2012-01-01

    Full Text Available Microwave-assisted extraction of pectin from lemon peels by using ionic liquid as alternative solvent was investigated. The extracted pectin was detected by Fourier transform infrared spectra. The extraction conditions were optimized through the different experiments in conjunction with the response surface methodology. A pectin yield of 24.68 % was obtained under the optimal parameters: the extraction temperature of 88°C, the extraction time of 9.6 min, and a liquid-solid ratio of 22.7 ml⋅g-1. The structure of the pretreated lemon peel samples and the samples after microwave-assisted extraction were characterized by a field emission scanning electron microscope.

  1. 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.

  2. The Role of Pectin Acetylation in the Organization of Plant Cell Walls

    DEFF Research Database (Denmark)

    Fimognari, Lorenzo

    adopt defined 3D organization to allow their composition/interactions to be tweaked upon developmental need. Failure to build functional cell wall architecture will affect plant growth and resistance to stresses. In this PhD dissertation I explored the role of pectin acetylation in controlling...... reduction in pectin and hemicellulose acetylation. We found that the increased resistance to pathogens in this mutant was due to the constitutive upregulation of defenses responses and the concomitant loss of integrity in the cell wall. Based on the results obtained in Manuscript I, we hypothesized...... that the loss of structural integrity in the cell wall was the underlying cause for triggering defenses response. This hypothesis was tested in Manuscript II. Through a suppressor screen of 30.000 Arabidopsis rwa2 plants and mapping of mutations by next generation sequencing, we pinpointed pectin deacetylation...

  3. 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.

  4. Transdermal delivery of chloroquine by amidated pectin hydrogel matrix patch in the rat.

    Science.gov (United States)

    Musabayane, C T; Munjeri, O; Matavire, T P

    2003-07-01

    The aim of the present study was to investigate the suitability of amidated pectin matrix patch for transdermal chloroquine delivery in an effort to mask the bitter taste when orally administered. Chloroquine has easily measurable outputs that are linked to increased renal Na+ excretion. We thus monitored urinary Na+ output in separate groups intravenously administered chloroquine or topically applied pectin hydrogel chloroquine matrix patch. Male groups of anesthetized Sprague-Dawley rats were placed on a continuous jugular infusion of 0.077 M NaCl at 150 microL min(-1). After 3 h equilibration period, consecutive 20 min urine collections were made over the subsequent 4 h of 1 h control, 1 h 20 min treatment, and 1 h 40 min recovery periods for measurements of urine flow and Na+ and K+ excretion rates. The effects of intravenous chloroquine infusion or topical application of pectin hydrogel chloroquine matrix patch were examined in rats in which the drug was added to the infusate or patch applied onto the shaved area during the 1 h 20 min treatment period. The animals were switched back to the infusate alone for the final 1 h 40 min recovery period. Vehicle infused animals acted as controls. Trunk blood was collected after the treatment period from parallel groups for chloroquine measurements. The plasma chloroquine concentrations following iv chloroquine or application of pectin chloroquine hydrogel matrix patch were 9.3 +/- 0.8 mg L(-1) and 7.3 +/- 1.1 mg L(-1) respectively (n = 7 in both groups). Chloroquine infusion and pectin chloroquine patch significantly (p pectin chloroquine patch matrix preparation has potential applications for transdermal delivery of chloroquine and perhaps in the management of malaria.

  5. Therapeutic effect of pectin on octylphenol induced kidney dysfunction, oxidative stress and apoptosis in rats.

    Science.gov (United States)

    Koriem, Khaled M M; Arbid, Mahmoud S; Emam, Kawther R

    2014-07-01

    Octylphenol (OP) is one of ubiquitous pollutants in the environment. It belongs to endocrine-disrupting chemicals (EDC). It is used in many industrial and agricultural products. Pectin is a family of complex polysaccharides that function as a hydrating agent and cementing material for the cellulose network. The aim of this study was to evaluate the therapeutic effect of pectin in kidney dysfunction, oxidative stress and apoptosis induced by OP exposure. Thirty-two male albino rats were divided into four equal groups; group 1 control was injected intraperitoneally (i.p) with saline [1 ml/kg body weight (bwt)], groups 2, 3 & 4 were injected i.p with OP (50 mg/kg bwt) three days/week over two weeks period where groups 3 & 4 were injected i.p with pectin (25 or 50 mg/kg bwt) three days/week over three weeks period. The results of the present study revealed that OP significantly decreased glutathione-S-transferase (GST), glutathione peroxidase (GPx), catalase (CAT), reduced glutathione (GSH), glutathione reductase (GR) and superoxide dismutase (SOD) levels while increased significantly lipid peroxidation (MDA), nitric oxide (NO) and protein carbonyls (PC) levels in the kidney tissues. On the other hand, OP increased serum urea and creatinine. Furthermore, OP increased significantly serum uric acid but decreased significantly the kidney weight. Moreover, OP decreased p53 expression while increased bcl-2 expression in the kidney tissue. The treatment with either dose of pectin to OP-exposed rats restores all the above parameters to approach the normal values where pectin at higher dose was more effective than lower one. These results were supported by histopathological investigations. In conclusion, pectin has antioxidant and anti-apoptotic activities in kidney toxicity induced by OP and the effect was dose-dependent.

  6. Characterization of microstructure, viscoelasticity, heterogeneity and ergodicity in pectin-laponite-CTAB-calcium nanocomposite hydrogels.

    Science.gov (United States)

    Joshi, Nidhi; Rawat, Kamla; Bohidar, H B

    2016-01-20

    In order to customize the viscoelastic properties of pectin gels, it is necessary to work on a composite platform. Herein, the gelation kinetics, and viscoelastic characterization of anionic polysaccharide pectin dispersion prepared in presence of nanoclay laponite are reported using dynamic light scattering and rheology measurements. The ratio Rg/Rh (Rg and Rh are radius of gyration and hydrodynamic radius respectively) determined from light scattering data revealed the presence of random coils of pectin chains inside the gel matrix. When nanoclay laponite was added to the pectin chains solution, two-phase separation was noticed instantaneously. Therefore, the surfactant cetyltrimethylammonium bromide [CTAB] was added to exfoliate the clay platelets in the dispersion, and also in its gel phase. The exfoliating agent cetyltrimethylammonium bromide ([CTAB]≈ cmc/10) helped to enhance the homogeneity and stability of the pectin-clay sols and gels. The storage and loss moduli (G' and G") of the composite gel changed significantly as function of nanoclay laponite content for concentration up to 0.03% (w/v) causing the softening of the gels (gel strength reduced by close to 50%) compared to pectin-calcium gel. However, as the concentration of nanoclay laponite was maintained between 0.01% and 0.03% (w/v), the gel rigidity (G') recovered by 30% (35-45 Pa). The transition from ergodic to non-ergodic state occurred during sol-gel transition owing to the presence of the nanoclay laponite. The gelation time was not too different from the ergodicity breaking time. Thus, the presence of nanoclay laponite in such minute concentration is shown to cause considerable change in the thermo-physical property of the composite gels. This material property modulation will facilitate designing of soft gels having storage modulus continuously varying in the wide range of 10-70 Pa while keeping the gelation temperature mostly unaltered.

  7. 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.

  8. Dispersion of halloysite loaded with natural antimicrobials into pectins: Characterization and controlled release analysis.

    Science.gov (United States)

    Gorrasi, Giuliana

    2015-01-01

    This paper reports the preparation and characterization of green composites based on pectins and nano-hybrids composed of halloysite nanotubes (HNTs) loaded with rosemary essential oil. Different hybrid percentages were mixed into a pectin matrix, by ball milling in the presence of water. Cast films were obtained and analyzed. Structural organization and physical properties (thermal, mechanical, barrier to water vapor) were correlated to the nano-hybrid content. A preliminary study on the kinetics of release of the rosmarinic acid, chosen as a model molecule, was also performed. This work showed the potential of these systems in the active packaging field where controlled release of active species is required.

  9. Anti-diabetic effect of citrus pectin in diabetic rats and potential mechanism via PI3K/Akt signaling pathway.

    Science.gov (United States)

    Liu, Yanlong; Dong, Man; Yang, Ziyu; Pan, Siyi

    2016-08-01

    This study was performed to investigate the anti-diabetic effect of citrus pectin in type 2 diabetic rats and its potential mechanism of action. The results showed that fasting blood glucose levels were significantly decreased after 4 weeks of citrus pectin administration. Citrus pectin improved glucose tolerance, hepatic glycogen content and blood lipid levels (TG, TC, LDL-c and HDL-c) in diabetic rats. Citrus pectin also significantly reduced insulin resistance, which played an important role in the resulting anti-diabetic effect. Moreover, after the pectin treatment, phosphorylated Akt expression was upregulated and GSK3β expression was downregulated, indicating that the potential anti-diabetic mechanism of citrus pectin might occur through regulation of the PI3K/Akt signaling pathway. Together, these results suggested that citrus pectin could ameliorate type 2 diabetes and potentially be used as an adjuvant treatment.

  10. Stabilization of a magnetic nano-adsorbent by extracted pectin to remove methylene blue from aqueous solution: A comparative studying between two kinds of cross-likened pectin

    Energy Technology Data Exchange (ETDEWEB)

    Rakhshaee, Roohan, E-mail: rakhshaei@iaurasht.ac.ir [Department of Applied Chemistry, Faculty of Science, Islamic Azad University, Rasht Branch, P.O. Box 41335-3516, Rasht (Iran, Islamic Republic of); Panahandeh, Mohammad [Environmental Research Institute of Jahad Daneshgahi (Iran, Islamic Republic of)

    2011-05-15

    The removal of methylene blue (MB) as a cationic dye from aqueous solution by the stabilized Fe{sub 3}O{sub 4} nano-particles with the extracted pectin from apple waste (FN-PA) increased due to using the cross-linked forms of the bound pectin on the nano-particles surface by glutaraldehyde (FN-PAG) and adipic acid (FN-PAA) as the cross-linking agents. This increase happened in spite of binding some of the adsorbent functional groups of pectin with nano-particles. It can be due to the local concentrate of other free functional groups after connecting with nano-scale particles. Thermodynamic studies showed that the adsorption equilibrium constant and the maximum adsorption capacities increased with increasing temperature for all of the nano-bioparticles. The kinetic followed the second-order models with the highest rate constants viz. 16.23, 19.76 and 23.04 (x10{sup -3} g/mg min) by FN-PAA. The adsorption force arrangement of MB by these nano-biosorbents regarding their activation energy was obtained as: FN-PAA > FN-PAG > FN-PA.

  11. Comparative effects of hawthorn (Crataegus pinnatifida Bunge) pectin and pectin hydrolyzates on the cholesterol homeostasis of hamsters fed high-cholesterol diets.

    Science.gov (United States)

    Zhu, Ru-Gang; Sun, Yan-Di; Li, Tuo-Ping; Chen, Gang; Peng, Xue; Duan, Wen-Bin; Zheng, Zheng-Zheng; Shi, Shu-Lei; Xu, Jing-Guo; Liu, Yan-Hua; Jin, Xiao-Yi

    2015-08-05

    This study aims to compare the effects of feeding haw pectin (HP), haw pectin hydrolyzates (HPH), and haw pectin pentasaccharide (HPPS) on the cholesterol metabolism of hypercholesterolemic hamsters induced by high-cholesterol diets. The animals were fed a standard diet (SD), high-cholesterol diet (HCD), or HCD plus HP, HPH, or HPPS at a dose of 300mg/kg body weight for 4weeks. Results showed that HPPS was more effective than HP and HPH in decreasing the body weight gain (by 38.2%), liver weight (by 16.4%), and plasma and hepatic total cholesterol (TC; by 23.6% and 27.3%, respectively) of hamsters. In addition, the bile acid levels in the feces were significantly higher by 39.8% and 132.8% in the HPH and HPPS groups than in the HCD group. Such changes were not noted in the HP group. However, the HP group had higher cholesterol excretion capacities than the HPH and HPPS groups by inhibiting cholesterol absorption in the diet, with a 21.7% increase in TC excretion and a 31.1% decrease in TC absorption. Thus, HPPS could be a promising anti-atherogenic dietary ingredient for the development of functional food to improve cholesterol metabolism.

  12. 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+.

  13. Addition of pectin and soy soluble polysaccharide affects the particle size distribution of casein suspensions prepared from acidified skim milk.

    Science.gov (United States)

    Liu, JinRu; Nakamura, Akihiro; Corredig, Milena

    2006-08-23

    Pectins are negatively charged polysaccharides employed as stabilizers in acidified milk dispersions, where caseins aggregate because of the low pH and serum separation needs to be prevented. The objective of this research was to study the effect of charge on the stabilizing functionality of the polysaccharide in acid milk drinks. Unstandardized pectins with various charges (as degree of esterification, DE) as well as soybean soluble polysaccharide (SSPS) were tested for their stabilizing behavior as a function of pH and concentration. Skim milk was acidified by glucono-delta-lactone and then homogenized in the presence of polysaccharide at different pH values (in the range from 4.2 to 3.0). Measurements of particle size distribution demonstrated that pectins with a DE of 71.4, 68.6, and 67.4 stabilized milk at pH > 4.0. Pectins with a lower DE (63.9%) needed a higher concentration (0.4%) at the same pH to show a monomodal distribution of particle sizes. Pectins with lower DE (milk, at pH milk dispersion was pH-dependent, and results were similar to those for samples containing pectin alone. This suggested that in the mixture, pectin dominated the behavior over SSPS, even when an excess of SSPS was added to the dispersions before homogenization.

  14. Optimizing delivery systems for cationic biopolymers: competitive interactions of cationic polylysine with anionic κ-carrageenan and pectin.

    Science.gov (United States)

    Lopez-Pena, Cynthia Lyliam; McClements, David Julian

    2014-06-15

    Polylysine is a cationic biopolymer with a strong antimicrobial activity against a wide range of microorganisms, however, its functional performance is influenced by its interactions with anionic biopolymers. We examined the stability of polylysine-pectin complexes in the presence of carrageenan, and vice versa. Polylysine-pectin or polylysine-carrageenan complexes were formed at mass ratios of 1:0 to 1:32 (pH 3.5), and then micro-electrophoresis, turbidity, microscopy, and isothermal titration calorimetry (ITC) were used to characterise them. Solutions containing polylysine-pectin complexes were slightly turbid and relatively stable to aggregation at high mass ratios, whereas those containing polylysine-carrageenan complexes were turbid and unstable to aggregation and precipitation. Pectin did not strongly interact with polylysine-carrageenan complexes, whereas carrageenan displaced pectin from polylysine-pectin complexes, which was attributed to differences in electrostatic attraction between polylysine, carrageenan, and pectin. These results have important implications for the design of effective antimicrobial delivery systems for foods and beverages.

  15. 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

  16. 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

    Pectin is a high value functional food ingredient widely used as a gelling agent and stabilizer. It is also an abundant, ubiquitous and multifunctional component of the cell walls of all land plants. Food scientists and plant scientists therefore share a common goal to better understand the struc...

  17. 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. ...

  18. Water sorption properties of HM-pectin and liposomes intended to alleviate dry mouth.

    Science.gov (United States)

    Adamczak, Małgorzata I; Martinsen, Ørjan G; Smistad, Gro; Hiorth, Marianne

    2016-06-15

    Pharmaceutical formulations intended for treatment of xerostomia (dry mouth) should be able to keep the oral mucosa hydrated for a prolonged period of time. The products already existing on the market contain water-soluble polymers, however their ability to moisturize the oral mucosa for a longer period of time seems limited. In this paper the sorption properties of water vapor of high-methoxylated pectin (HM-pectin, a hydrophilic biopolymer) and phosphatidylcholine-based (Soya-PC) liposomes have been studied and compared using a gravimetric method. The kinetics of water desorption and sorption have been recorded over the relative humidity range RH=95-0-95%, at 35°C. The obtained isotherms were found to be well described by the n-layer Brunauer-Emmet-Teller (BET) adsorption model. The water isotherms on HM-pectin were Type II (IUPAC), while water isotherms on liposomes were Type III. The maximum water sorption capacity of liposomes (1.2mg water per mg of adsorbent at 95% RH) was found to be twice as high as for pectin. Due to the slower water release from the liposomes, as well as their high water sorption capacity, they seem to have great potential in relieving the symptoms of dry mouth syndrome.

  19. Effect of cotton pectin content and bioscouring on alkyl-dimethyl-benzyl-ammonium chloride adsorption

    Science.gov (United States)

    Our previous research has shown both the rate and the total amount of alkyl-dimethyl-benzyl-ammonium chloride (ADBAC) exhausted from a bulk solution of ADBAC are significantly greater for greige cotton nonwovens than cotton nonwovens that have been both scoured and bleached. The presence of pectin ...

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

    Science.gov (United States)

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

    2016-11-01

    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.

  1. 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.

  2. Improvement of starch digestion using α-amylase entrapped in pectin-polyvinyl alcohol blend.

    Science.gov (United States)

    Cruz, Maurício; Fernandes, Kátia; Cysneiros, Cristine; Nassar, Reginaldo; Caramori, Samantha

    2015-01-01

    Polyvinyl alcohol (PVA) and pectin blends were used to entrap α-amylase (Termamyl) using glutaraldehyde as a cross-linker. The effect of glutaraldehyde concentration (0.25, 0.5, 0.75, 1.0, and 1.25%) on the activity of the immobilized enzyme and rate of enzyme released was tested during a 24 h period. Characteristics of the material, such as scanning electron microscopy (SEM), tensile strength (TS), elongation, and rate of dissolution in water (pH 5.7), ruminal buffering solution (pH 7.0), and reactor containing 0.1 mol L(-1) sodium phosphate buffer (pH 6.5), were also analyzed. SEM results showed that the surfaces of the pectin/PVA/amylase films were highly irregular and rough. TS values increased as a function of glutaraldehyde concentration, whereas percentage of elongation (%E) decreased. Pectin/PVA/amylase films presented similar values of solubility in the tested solvents. The material obtained with 0.25% glutaraldehyde performed best with repeated use (active for 24 h), in a phosphate buffer reactor. By contrast, the material obtained with 1.25% glutaraldehyde presented higher performance during in vitro testing using an artificial rumen. The results suggest that pectin/PVA/amylase is a highly promising material for biotechnological applications.

  3. Improvement of Starch Digestion Using α-Amylase Entrapped in Pectin-Polyvinyl Alcohol Blend

    Directory of Open Access Journals (Sweden)

    Maurício Cruz

    2015-01-01

    Full Text Available Polyvinyl alcohol (PVA and pectin blends were used to entrap α-amylase (Termamyl using glutaraldehyde as a cross-linker. The effect of glutaraldehyde concentration (0.25, 0.5, 0.75, 1.0, and 1.25% on the activity of the immobilized enzyme and rate of enzyme released was tested during a 24 h period. Characteristics of the material, such as scanning electron microscopy (SEM, tensile strength (TS, elongation, and rate of dissolution in water (pH 5.7, ruminal buffering solution (pH 7.0, and reactor containing 0.1 mol L−1 sodium phosphate buffer (pH 6.5, were also analyzed. SEM results showed that the surfaces of the pectin/PVA/amylase films were highly irregular and rough. TS values increased as a function of glutaraldehyde concentration, whereas percentage of elongation (%E decreased. Pectin/PVA/amylase films presented similar values of solubility in the tested solvents. The material obtained with 0.25% glutaraldehyde performed best with repeated use (active for 24 h, in a phosphate buffer reactor. By contrast, the material obtained with 1.25% glutaraldehyde presented higher performance during in vitro testing using an artificial rumen. The results suggest that pectin/PVA/amylase is a highly promising material for biotechnological applications.

  4. Effects of pectin supplementation on the fermentation patterns of different structural carbohydrates in rats

    NARCIS (Netherlands)

    Tian, Lingmin; Scholte, Jan; Borewicz, Klaudyna; Bogert, van den Bartholomeus; Smidt, Hauke; Scheurink, Anton J.W.; Gruppen, Harry; Schols, Henk A.

    2016-01-01

    Scope: We aimed to investigate and compare the effects of four types of pectins on dietary fiber (DF) fermentation, microbiota composition, and short chain fatty acid (SCFA) production throughout the large intestine in rats. Methods and results: Male Wistar rats were given diets supplemented with

  5. Composite Films from Sodium Alginate and High Methoxyl Pectin - Physicochemical Properties and Biodegradation in Soil

    Directory of Open Access Journals (Sweden)

    Ayten O. Solak

    2014-12-01

    Full Text Available The increased public attention on the waste pollution and the awareness of the hard environmental problems is the reason for the need of new materials which are susceptible to degradation in nature for a short period of time. The biopolymer films and coatings based on renewable natural sources are suitable for obtaining of biodegradable packaging. The newly developed composite films based on sodium alginate and apple high methoxyl pectin were studied for total soluble matter, swelling in water, water vapors transmission rate and biodegradation in soil. The analysis of their behavior in water medium showed a considerably higher rate and degree of dissolution of the pectin monocomponent film compared to the composite and alginate films. The composite alginate-pectin films showed lower water vapors transmission rate even under extreme conditions (38ºC, RH 90 % compared to the monocomponent films. All investigated films degraded in soil up to 80 days. The good barrier properties to water vapors and the complete biodegradation in soil make the films based on sodium alginate and high methoxyl pectin potential ecological materials for packing and coating of foods and pharmaceutical products.

  6. 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....

  7. Eudragit-coated aceclofenac-loaded pectin microspheres in chronopharmacological treatment of rheumatoid arthritis.

    Science.gov (United States)

    Ramasamy, Thiruganesh; Ruttala, Hima Bindu; Shanmugam, Suresh; Umadevi, Subbiah Kandasamy

    2013-02-01

    The aim of this study was to develop a pectin-based colon-specific multiparticulate delivery system. Aceclofenac was used as a model drug owing to its potential therapeutic efficacy in rheumatoid arthritis. Pectin microspheres were prepared using emulsion dehydration technique. These microspheres were coated with Eudragit S-100 using solvent evaporation method. The effect of different variables (polymer, emulsifier, stirring speed and stirring time) was investigated in terms of size, surface morphology, entrapment efficiency, in vitro release and in vivo studies. The size of uncoated microspheres ranged from 30 to 55 µm and exhibited 5-40% of drug release in the upper gastrointestinal tract; however, continuous high release of drug was observed at colonic pH. In addition, the release of drug from the microspheres was found to be higher in the presence of rat cecal contents with maximum release at the 8th hour. This is one of the prerequisites for the effective treatment of rheumatoid arthritis, indicating the effect of colonic enzymes on the pectin microspheres. In vivo studies suggest the maintenance of therapeutic concentration of drug for 24 h with significant anti-inflammatory effect. Therefore, these findings clearly suggest that the Eudragit-coated pectin microspheres offer an exciting mode of aceclofenac delivery to colon in the chronopharmacological treatment of rheumatoid arthritis.

  8. Biocompatibility of Pectin-Protein Gels and Microencapsulates: In Vivo Study on Rats

    Science.gov (United States)

    Pectin-protein complex hydrogel beads were tested in vivo on rats. The beads were pre-loaded with a model drug, piroxicam (PX), in ethanol at different loading rates. The rats were starved 8 hr prior to experiment. The rats were then fed with the beads. Blood samples were taken in 2, 4, 6, 12, and 2...

  9. 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...

  10. Influence of pectin supplementation on feed fermentation characteristics in rats and pigs

    NARCIS (Netherlands)

    Tian, L.

    2016-01-01

    The physiological effects of dietary fiber (DFs) depend on several factors including structural features of the DFs, composition and activity of colonic microbiota, and products formed during fermentation. In this thesis, the influence of pectin supplementation to feed fermentation characteristics i

  11. Nutraceutically inspired pectin-Mg(OH)₂ nanocomposites for bioactive packaging applications.

    Science.gov (United States)

    Moreira, Francys K V; De Camargo, Lais A; Marconcini, José M; Mattoso, Luiz H C

    2013-07-24

    This paper reports on the development of bioactive edible films based on pectin as a dietary matrix and magnesium hydroxide (Mg(OH)2) nanoplates as a reinforcing filler. Nanocomposites of high-methoxyl (HM) and low-methoxyl (LM) pectins were prepared using the casting method at concentrations of Mg(OH)2 ranging from 0.5 to 5 wt %. Atomic force microscopy and FTIR spectroscopy were employed to characterize the nanocomposite structure. The tensile properties and thermal stability of the nanocomposites were also examined to ascertain the effect of Mg(OH)2 inclusion and degree of methoxylation. The results provided evidence that the Mg(OH)2 nanoplates were uniformly dispersed and interacted strongly with the film matrix. The mechanical and thermal properties were significantly improved in the nanocomposite films compared to the control. Mg(OH)2 nanoplates were more effective in improving properties of LM pectin. Preliminary migration studies using arugula leaves confirmed that pectin-Mg(OH)2 nanocomposites can release magnesium hydroxide by contact, demonstrating their potential for magnesium supplementation in bioactive packaging.

  12. Injectable pectin hydrogels produced by internal gelation: pH dependence of gelling and rheological properties.

    Science.gov (United States)

    Moreira, Helena R; Munarin, Fabiola; Gentilini, Roberta; Visai, Livia; Granja, Pedro L; Tanzi, Maria Cristina; Petrini, Paola

    2014-03-15

    The production of injectable pectin hydrogels by internal gelation with calcium carbonate is proposed. The pH of pectin was increased with NaOH or NaHCO3 to reach physiological values. The determination of the equivalence point provided evidence that the pH can be more precisely modulated with NaHCO3 than with NaOH. Degradation and inability to gel was observed for pectin solutions with pH 5.35 or higher. Therefore, pectin solutions with pH values varying from 3.2 (native pH) to 3.8 were chosen to produce the gels. The increase of the pH for the crosslinked hydrogels, as well as the reduction of the gelling time and their thickening, was dependent upon the amount of calcium carbonate, as confirmed by rheology. Hydrogel extracts were not cytotoxic for L-929 fibroblasts. On the overall, the investigated formulations represent interesting injectable systems providing an adequate microenvironment for cell, drug or bioactive molecules delivery.

  13. Development of pH sensitive polyacrylamide grafted pectin hydrogel for controlled drug delivery system.

    Science.gov (United States)

    Sutar, Prashant B; Mishra, Rakesh K; Pal, Kunal; Banthia, Ajit K

    2008-06-01

    In the present study an attempt was made to graft polyacrylamide on pectin. The grafted polymer was characterized by FTIR spectroscopy, differential scanning calorimetry and X-ray diffraction. Rheological property of pectin solution was compared with the product solution. The grafted polymer was cross-linked with varying amount of glutaraldehyde. The swelling properties of the cross-linked product were also studied. The salicylic acid, an antipyretic drug, was incorporated in the cross-linked gel as a model drug and the drug release studies were done in a modified Franz's diffusion cell. The effect of cross-linking density on the release property of salicylic acid was studied through the cross-linked product. The product showed better film forming property and gelling property than pectin. The comparative rheological properties of pectin and grafted copolymer indicated change in the property of the product. FTIR studies indicated incorporation of amide group. Differential scanning calorimetry and XRD suggested formation of a new polymer. Swelling study indicated pH dependent swelling of the cross-linked hydrogel. Salicylic acid release indicated pH dependent release from the hydrogel.

  14. Synthesis and characterization of pectin/PVP hydrogel membranes for drug delivery system.

    Science.gov (United States)

    Mishra, Rakesh K; Datt, Mahesh; Banthia, Ajit K

    2008-01-01

    The purpose of the present study was to develop and design pectin and polyvinyl pyrrolidone (PVP) blended hydrogel membranes (PEVP), with different pectin: PVP ratios (1:0.2, 1:0.4, 1:0.6, 1:0.8 and 1:1 w/w), which were prepared by using a conventional solution casting technique. An attempt has been made to characterize the hydrogel membranes by various instrumental techniques like, FTIR (Fourier transform infrared) spectroscopy, X-ray diffraction (XRD), Differential scanning calorimetry (DSC), tensile strength test and scanning electron microscopy (SEM). The release patterns of the drug (salicylic acid) from the hydrogel membrane were done in three different release mediums (pH 1.4, pH 7.4 and distilled water) and samples were analyzed spectrophotometrically at 294 nm wavelength on a UV Vis spectrophotometer. MTT assay was done to ensure cytocompatibility of the pectin/PVP hydrogel membranes using B16 melanoma cells. FTIR spectroscopy indicated the presence of secondary amide (I) absorption bands. The XRD study shows decrease in crystallinity of the hydrogel membranes with increase in PVP ratio. DSC study shows an increase in T(g) of pectin after blending with PVP. It was found that tensile strength increases with increasing PVP ratios in the hydrogel membranes. The prepared hydrogel membranes were found to be biocompatible with B16 melanoma cells.

  15. 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 measure...

  16. Encapsulation of a model compound in pectin delays its release from a biobased polymeric material

    Science.gov (United States)

    A model compound was encapsulated in pectin and then extruded with thermoplastic starch to form a composite. The intended product was a food-contact tray made of biobased polymers infused with an anti-microbial agent; however, caffeine was used as the model compound in the preliminary work. The mode...

  17. Formation and Properties of Protamine/Pectin LbL-Coatings

    Science.gov (United States)

    Hileuskaya, K.; Agabekov, V. E.

    The adsorption regularities of protamine sulfate and pectin on the surfaces from solution with different ionic strength were investigated in situ using quartz substrate via the quartz crystal microbalance technique. Both polymers were observed to absorb according to Langmuir's adsorption isotherm. The value of Langmuir adsorption constant (k) is equal to 74,48 and 1,12 sm3/μg for pectin and protamine respectively. Maximum amount of biopolymer (A∞) adsorbed on resonator is 0,87 μg/sm2 for Pect and 0,57 μg/sm2 for PtS. Ultrathin (pectin)8 LbL films were formed and adsorption kinetics of both polyions were studied. The rate constant of protamine and pectin adsorption are (3,9 ± 0,9)·10-2 s-1 and (3,4 ± 0,3)·10-2 s-1 respectively. It was shown, that film thickness increases by 2.5 times with polymers concentration in solution increasing from 0.1 to 3.0 mg/ml.

  18. Environmentally Friendly Preparation of Gold and Silver Nanoparticles for Sers Applications Using Biopolymer Pectin

    Science.gov (United States)

    Balachandran, Y. L.; Panarin, A. Y.; Khodasevich, I. A.; Terekhov, S. N.; Gutleb, A. C.; Girijaa, S.

    2015-01-01

    A facile, one-step, and environmentally friendly fabrication of anisotropic gold nanostructures and size-controlled spherical silver nanoparticles (NP) using biopolymer pectin is reported. The reduction of Au and Ag ions was carried out at room temperature using an increasing concentration of pectin, which acts as the single source of reducing and stabilizing agent. The as-formed NPs were studied by UV-vis, infrared Fourier transform and surface-enhanced Raman spectroscopies, as well as transmission electron microscopy and energy dispersive X-ray spectroscopy. A high yield of anisotropic gold nanostructures was observed at low concentrations of pectin, while its increase results in the formation of smaller sharp edged perfect triangles with a considerable number of quasi-spherically shaped gold NP. On the other hand, the size of spherical silver NP decreased as the biopolymer concentration in the solution increased. The surface-enhanced Raman scattering enhancement of different NPs was evaluated using a Cu-complex of cationic tetrakis(4-N-methylpyridyl)porphyrin as a probe molecule at 441.6 and 532 nm excitation. Great enhancement of Raman signal was obtained with a pectin-silver NP and for most of them their levels were higher than that for the routinely synthesized citrate silver NP.

  19. Optimization of pectin extraction from banana peels with citric acid by using response surface methodology.

    Science.gov (United States)

    Oliveira, Túlio Ítalo S; Rosa, Morsyleide F; Cavalcante, Fabio Lima; Pereira, Paulo Henrique F; Moates, Graham K; Wellner, Nikolaus; Mazzetto, Selma E; Waldron, Keith W; Azeredo, Henriette M C

    2016-05-01

    A central composite design was used to determine effects of pH (2.0-4.5), extraction temperature (70-90 °C) and time (120-240 min) on the yield, degree of methoxylation (DM) and galacturonic acid content (GA) of pectins extracted from banana peels with citric acid. Changes in composition during the main steps of pectin extraction were followed by Fourier transform infrared (FTIR) spectroscopy. FTIR was also used to determine DM and GA of pectins. Harsh temperature and pH conditions enhanced the extraction yield, but decreased DM. GA presented a maximum value at 83 °C, 190 min, and pH 2.7. The yield of galacturonic acid (YGA), which took into account both the extraction yield and the pectin purity, was improved by higher temperature and lower pH values. The optimum extraction conditions, defined as those resulting in a maximum YGA while keeping DM at a minimum of 51%, were: 87 °C, 160 min, pH 2.0.

  20. Performance of Inclined Baffle Column for Pectin Continuous Extraction Process from Cocoa Peel (Theobromacacao

    Directory of Open Access Journals (Sweden)

    Soemargono

    2016-01-01

    Full Text Available Pectin from cocoa peel was successfully prepared by extraction method in the bubble column reactor. The process could be carried out in batch and continuous, with co-current or counter current flow. Bubble pipe reactor with inclined baffle is expected to reduce the problem from gas flow patterns, jagged sloping bulkhead serves as a bubble breaker that could replace mechanical stirrer. In this study the reactor column sloping bulkhead was used as extractor to recover pectin in the cocoa peel by citric acid (1 N solvent. Cocoa peel paste and citric acid were entered to the top of the column at 1 : 1 rate ratio by streamed using dosing pump. Nitrogen gas as a medium stirrer flowed counter current from the bottom of the column. Once extraction was completed, the liquid then precipitated by acid alcohol. Pectin solids were washed with alcohol (96%. The temperature of extraction process is maintained at 70° C. The residence time in the column material was determined by feed flow rate (cocoa paste and citric acid, and the volume of suspension that remains in the reactor (V. Residence time equation obtained is: t = (7045.86G-0.1275/L. The yield of yellowish white precipitate reached up to 5.2973% and methoxyl concentration reached 5,21% for 72 minutes. The experiment shows that the continuous extraction process of pectin in baffle columns is better than batch process.

  1. Optimization for Ultrasound-microwave Assisted Extraction of Pectin from Jujube Waste using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Fengqi Bai

    2015-02-01

    Full Text Available Optimization of conditions for Jujube pectin extraction was investigated using Response Surface Methodology (RSM. Extraction parameters which are employed in this study are Liquid-Solid Ratio (LSR (5-15, pH (1.5-2.5, ultrasonic time (10-20 min and microwave irradiation time (40-60 s and they were optimized using a four factor three levels Box-Behnken response surface design (BBD coupled with desirability function methodology. The results showed that, all the process variables have significant effect on the yield of pectin. The satisfactory conditions for Jujube pectin extraction were obtained as follows: 10.03 mL/g of LSR, 1.97 of pH of sulfuric, 17.66 min of ultrasonic time and 52.73 s of microwave irradiation time. Among the studied factors, microwave irradiation time had the greatest influence on yield. Under these conditions, the experimental yield of Jujube pectin was 1.95±0.06%, which is well in close agreement with the value predicted by the model.

  2. Structural alteration of cell wall pectins accompanies pea development in response to cold.

    Science.gov (United States)

    Baldwin, Laëtitia; Domon, Jean-Marc; Klimek, John F; Fournet, Françoise; Sellier, Hélène; Gillet, Françoise; Pelloux, Jérôme; Lejeune-Hénaut, Isabelle; Carpita, Nicholas C; Rayon, Catherine

    2014-08-01

    Pea (Pisum sativum) cell wall metabolism in response to chilling was investigated in a frost-sensitive genotype 'Terese' and a frost-tolerant genotype 'Champagne'. Cell walls isolated from stipules of cold acclimated and non-acclimated plants showed that cold temperatures induce changes in polymers containing xylose, arabinose, galactose and galacturonic acid residues. In the tolerant cultivar Champagne, acclimation is accompanied by increases in homogalacturonan, xylogalacturonan and highly branched Rhamnogalacturonan I with branched and unbranched (1→5)-α-arabinans and (1→4)-β-galactans. In contrast, the sensitive cultivar Terese accumulates substantial amounts of (1→4)-β-xylans and glucuronoxylan, but not the pectins. Greater JIM7 labeling was observed in Champagne compared to Terese, indicating that cold acclimation also induces an increase in the degree of methylesterification of pectins. Significant decrease in polygalacturonase activities in both genotypes were observed at the end of cold acclimation. These data indicate a role for esterified pectins in cold tolerance. The possible functions for pectins and their associated arabinans and galactans in cold acclimation are discussed.

  3. Stabilization of oil-in-water emulsions by enzyme catalyzed oxidative gelation of sugar beet pectin

    DEFF Research Database (Denmark)

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

    2013-01-01

    Enzyme catalyzed oxidative cross-linking of feruloyl groups can promote gelation of sugar beet pectin (SBP). It is uncertain how the enzyme kinetics of this cross-linking reaction are affected in emulsion systems and whether the gelation affects emulsion stability. In this study, SBP (2.5% w...

  4. Overexpression of the plg1 gene encoding pectin lyase in Penicillium griseoroseum.

    Science.gov (United States)

    Cardoso, Patrícia Gomes; Ribeiro, João Batista; Teixeira, Janaina Aparecida; de Queiroz, Marisa Vieira; de Araújo, Elza Fernandes

    2008-03-01

    The pectin lyase (PL) is an industrially important enzyme since it is used for maceration and clarification in the process of fruit juice production in food industries. In order to increase the yields of pectin lyase we cloned the plg1 (pectin lyase 1) from Penicillium griseoroseum gene under the control of the strong constitutive promoter of the glyceraldehyde-3-phosphate dehydrogenase gene (gpdA) and the terminator region of the tryptophan synthetase (trpC) gene from Aspergillus nidulans (plasmid pAN52-Plg1) and transformed this construct into the P. griseoroseum strain PG63. One of the pAN52-Plg1 multi-copy transformants (strain 105) grown in culture medium containing glucose or sugar cane juice showed PL activities of 4,804 or 5,202 U ml(-1) respectively, which represented 57- and 132-fold increases. In addition, the apparent specific activity of PL produced by this strain was much higher than the one observed for a commercial pectinase preparation. Evaluation of the extracellular proteins in the culture supernatant of strain 105 by SDS-PAGE showed the presence of a clear and strong band of approximately 40 kDa that probably corresponds to PL. The enzyme yields reported here demonstrate that the system we developed is able to express pectin lyase at levels comparable to, or exceeding, previously reported data.

  5. Antimicrobial activity of nisin incorporated in pectin and polylactic acid composite films against Listeria monocytogenes

    Science.gov (United States)

    Extruded composite films from 20% pectin and 80% polylactic acids (PLA) were developed and nisin was loaded into films by a diffusion post extrusion. Inhibitory activities of the films against Listeria monocytogenes were evaluated in brain heart infusion (BHI) broth, liquid egg white and orange juic...

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

    Science.gov (United States)

    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.

  7. New insights into the mucoadhesion of pectins by AFM roughness parameters in combination with SPR

    DEFF Research Database (Denmark)

    Joergensen, Lars; Klösgen, Beate; Simonsen, Adam Cohen;

    2011-01-01

    The object of this study was to assess the mucoadhesion of the three main commercially available types of pectin by atomic force microscopy (AFM) and surface Plasmon resonance (SPR). Polyacrylic acid and polyvinyl pyrrolidone were used as positive and negative control, respectively. Image analysis...

  8. Temperature-independent pectin gel method for aerobic plate count in dairy and nondairy food products: collaborative study.

    Science.gov (United States)

    Roth, J N

    1988-01-01

    Ten laboratories participated in a collaborative study to compare the pectin-based plate count (PC) Redigel method with the aerobic plate count and standard plate count agar-based standard methods for the estimation of total bacterial counts in 9 different nondairy food and dairy food products. The foods were cream, homogenized milk, raw milk, cheese, raw chicken, raw oysters, frozen broccoli, flour, and spices. Each laboratory analyzed 6 samples (3 sample pairs) of each food group. Counts obtained by the pectin-based plate count and agar-based plate count methods differed significantly (P less than 0.05) only for homogenized milk, where the pectin gel method resulted in higher counts. The actual counts were higher in the pectin gel method in 8 of the 9 food groups. The log means for pectin gel and agar-based media, respectively, for the 9 food groups were: cream 8.106 and 7.844; homogenized milk 8.642 and 8.231; raw milk 8.711 and 8.423; chicken 7.654 and 7.645; oysters 7.201 and 7.180; broccoli 7.102 and 6.798; cheese 8.045 and 8.055; flour 4.112 and 3.988; spice 5.379 and 5.314. The repeatability standard deviations favored the pectin gel method in 6 of the 9 foods tested. The reproducibility standard deviations favored the pectin gel method in 7 of the 9 foods tested. These results strongly support the suitability of the pectin gel method as an alternative to agar-based plate count and other methods for total bacterial counts in nondairy and dairy food products. The pectin gel method has been adopted official first action.

  9. 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.

    2014-01-01

    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 (1H NMR) and carbon-13 nuclear magnetic resonance spectroscopy (13C 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.

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

    Directory of Open Access Journals (Sweden)

    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. 

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

    DEFF Research Database (Denmark)

    Stranne, Maria

    wall acetylation (Chapter 2), identification of a candidate gene required for acetylation of pectin (Chapter 3), screening of pectin mutants for susceptibility to the nectrotrophic fungal pathogen Botrytis cinerea (Chapter 4), and identification and functional characterization of an arabinan......-degrading enzyme secreted by B. cinerea during infection of plants (Chapter 5). The results described resulted in valuable new knowledge regarding the role of pectin acetylation and arabinosylation in the model plant Arabidopsis thaliana documented in three published research papers, one manuscript and one...

  12. 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.

  13. 苹果果胶研究进展%Research progress of apple pectin

    Institute of Scientific and Technical Information of China (English)

    孙立军; 郭玉蓉; 田兰兰

    2012-01-01

    苹果(Malus pumila Mill.)是我国北方广泛种植的经济作物。近年来,很多学者从苹果渣中提取分离得到苹果果胶。现代医学和生物学研究表明,苹果果胶具有抗氧化、降血脂、抗菌及抗癌的功效。本文介绍了苹果果胶的结构、组分分级与特性研究,着重阐述了目前国内外对于苹果果胶的提取、分离的最新进展及其生物活性,讨论了目前研究中存在的问题,并对其发展前景进行了展望。%Apple(Malus pumila Mill.) tree is a common kind of plant in the northern part of our country.In recent years,apple pectin has been isolated from apple pomace by many researchers.Researchers in medicine and biology have proved that apple pectin has many biology activities such as oxidation resistance,hypolipemic,antibiosis and anticancer.In this review,structure of apple pectin,pectin fraction and properties of different molecular weights were reviewed and the latest methods of extraction,biological activities,problems of studies on apple pectin and its prospects were also elaborated.

  14. Extraction and characterization of Foeniculum vulgare pectins and their use for preparing biopolymer films in the presence of phaseolin protein.

    Science.gov (United States)

    Giosafatto, Concetta V L; Mariniello, Loredana; Ring, Steve

    2007-02-21

    Pectins from Foeniculum vulgare were extracted under acidic conditions. The obtained pectins were mainly composed of uronic acid but also contained traces of rhamnose, galactose, and arabinose. Extracted pectins were used as a carbohydrate source to prepare biopolymer films in the absence and in the presence of phaseolin protein. The swelling characteristics of the films were examined as a function of ionic strength, pH, and the applied osmotic stress. The swelling behavior was dominated by a Donnan-type effect, which decreases with increasing ionic strength and counterion valency. In all cases the swelling of films containing phaseolin was reduced, suggesting a network formation between protein and pectins. Mechanical property studies have also estimated the validity of the obtained novel biopolymer films in terms of mechanical resistance.

  15. The effects of pectin on hawthorn processing%果胶对山楂加工的影响

    Institute of Scientific and Technical Information of China (English)

    于铭章

    2009-01-01

    Pectin is a natural polymer with macromolecule. There is pectin in all fmit. h has a role of coacervation tenacity and emulsification. Pectin content reaches 6.4% in hawthorn, ranking the fast position in all fruits. Pectin- rich material determines the specific processing perfonnance and unique products in hawthorn, making it rich and varied products.%果胶是一种天然高分子化合物,广泛存在于各种水果中,具有凝胶、粘韧、增稠乳化等作用.山楂中果胶含量达6.4%,居所有水果之首.丰富的果胶物质决定着山楂特有的加工性能和特有的加工产品,从而使其加工产品丰富多彩.

  16. Preparation and chemical and biological characterization of a pectin/chitosan polyelectrolyte complex scaffold for possible bone tissue engineering applications.

    Science.gov (United States)

    Coimbra, P; Ferreira, P; de Sousa, H C; Batista, P; Rodrigues, M A; Correia, I J; Gil, M H

    2011-01-01

    In this work, porous scaffolds obtained from the freeze-drying of pectin/chitosan polyelectrolyte complexes were prepared and characterized by FTIR, SEM and weight loss studies. Additionally, the cytotoxicity of the prepared scaffolds was evaluated in vitro, using human osteoblast cells. The results obtained showed that cells adhered to scaffolds and proliferated. The study also confirmed that the degradation by-products of pectin/chitosan scaffold are noncytotoxic.

  17. Design, development and in vitro evaluation of sennosides tablets containing pectin HPMC for colonic drug delivery

    OpenAIRE

    Momin Munira; Pundarikakshudu K

    2007-01-01

    The purpose of the present investigation was to achieve colon specific delivery of sennosides using the polysaccharide pectin as a compression-coating agent. In this study, pectin along with hydroxypropylmethylcellulose was used for compression coating of the core tablets of calcium sennoside. Drug dissolution and erosion studies were carried out in pH 1.2 and phosphate buffer pH 7.4 using a pectinolytic enzyme. The system was designed based on the gastrointestinal transit time concept, assum...

  18. Oregano essential oil-pectin edible films as anti-quorum sensing and food antimicrobial agents

    Directory of Open Access Journals (Sweden)

    Victoria eAlvarez

    2014-12-01

    Full Text Available Edible films can be used as carriers for antimicrobial compounds to assure food safety and quality; in addition, pathogenesis of food bacteria is related to a cell to cell communication mechanism called quorum sensing (QS. Oregano essential oil (OEO has proved to be useful as food antimicrobial; however, its food applications can be compromised by the volatile character of its active constituents. Therefore, formulation of edible films containing OEO can be an alternative to improve its food usages. QS inhibitory activity of OEO and pectin-OEO films was evaluated using Chromobacterium violaceum as bacterial model. Additionally, antibacterial activity was tested against Escherichia coli O157:H7, Salmonella Choleraesuis, Staphylococcus aureus, and Listeria monocytogenes. OEO was effective to inhibit bacterial growth at MIC of 0.24 mg/mL for all tested bacteria and MBC of 0.24, 0.24, 0.48, and 0.24 mg/mL against E. coli O157:H7, S. Choleraesuis, S. aureus, and L. monocytogenes, respectively. Pectin-films incorporated with 36.1 and 25.9 mg/mL of OEO showed inhibition diameters of 16.3 and 15.2 mm for E. coli O157:H7; 18.1 and 24.2 mm for S. Choleraesuis; 20.8 and 20.3 mm for S. aureus; 21.3 and 19.3 mm for L. monocytogenes, respectively. Pectin-OEO film (15.7 mg/mL was effective against E. coli O157:H7 (9.3 mm, S. aureus (9.7 mm, and L. monocytogenes (9.2 mm, but not for S. Choleraesuis. All concentrations of OEO (0.0156, 0.0312, 0.0625 and 0.125 mg/mL and pectin-OEO films (15.7, 25.9 and 36.1 mg/mL showed a significant anti-QS activity expressed as inhibition of violacein production by C. violaceum. Additionally, the application of pectin-OEO films was effective reducing total coliforms, yeast, and molds of shrimp and cucumber slices stored at 4 °C during 15 d. These results demonstrated the potential of pectin films enriched with OEO as food related microorganisms and QS inhibitors.

  19. Oregano essential oil-pectin edible films as anti-quorum sensing and food antimicrobial agents

    Science.gov (United States)

    Alvarez, Maria V.; Ortega-Ramirez, Luis A.; Gutierrez-Pacheco, M. Melissa; Bernal-Mercado, A. Thalia; Rodriguez-Garcia, Isela; Gonzalez-Aguilar, Gustavo A.; Ponce, Alejandra; Moreira, Maria del R.; Roura, Sara I.; Ayala-Zavala, J. Fernando

    2014-01-01

    Edible films can be used as carriers for antimicrobial compounds to assure food safety and quality; in addition, pathogenesis of food bacteria is related to a cell to cell communication mechanism called quorum sensing (QS). Oregano essential oil (OEO) has proved to be useful as food antimicrobial; however, its food applications can be compromised by the volatile character of its active constituents. Therefore, formulation of edible films containing OEO can be an alternative to improve its food usages. QS inhibitory activity of OEO and pectin-OEO films was evaluated using Chromobacterium violaceum as bacterial model. Additionally, antibacterial activity was tested against Escherichia coli O157:H7, Salmonella Choleraesuis, Staphylococcus aureus, and Listeria monocytogenes. OEO was effective to inhibit bacterial growth at MIC of 0.24 mg/mL for all tested bacteria and MBC of 0.24, 0.24, 0.48, and 0.24 mg/mL against E. coli O157:H7, S. Choleraesuis, S. aureus, and L. monocytogenes, respectively. Pectin-films incorporated with 36.1 and 25.9 mg/mL of OEO showed inhibition diameters of 16.3 and 15.2 mm for E. coli O157:H7; 18.1 and 24.2 mm for S. Choleraesuis; 20.8 and 20.3 mm for S. aureus; 21.3 and 19.3 mm for L. monocytogenes, respectively. Pectin-OEO film (15.7 mg/mL) was effective against E. coli O157:H7 (9.3 mm), S. aureus (9.7 mm), and L. monocytogenes (9.2 mm), but not for S. Choleraesuis. All concentrations of OEO (0.0156, 0.0312, 0.0625 and 0.125 mg/mL) and pectin-OEO films (15.7, 25.9 and 36.1 mg/mL) showed a significant anti-QS activity expressed as inhibition of violacein production by C. violaceum. Additionally, the application of pectin-OEO films was effective reducing total coliforms, yeast, and molds of shrimp and cucumber slices stored at 4°C during 15 d. These results demonstrated the potential of pectin films enriched with OEO as food related microorganisms and QS inhibitors. PMID:25566215

  20. Ultrasound-assisted extraction of pectins from grape pomace using citric acid: a response surface methodology approach.

    Science.gov (United States)

    Minjares-Fuentes, R; Femenia, A; Garau, M C; Meza-Velázquez, J A; Simal, S; Rosselló, C

    2014-06-15

    An ultrasound-assisted procedure for the extraction of pectins from grape pomace with citric acid as the extracting agent was established. A Box-Behnken design (BBD) was employed to optimize the extraction temperature (X1: 35-75°C), extraction time (X2: 20-60 min) and pH (X3: 1.0-2.0) to obtain a high yield of pectins with high average molecular weight (MW) and degree of esterification (DE) from grape pomace. Analysis of variance showed that the contribution of a quadratic model was significant for the pectin extraction yield and for pectin MW whereas the DE of pectins was more influenced by a linear model. An optimization study using response surface methodology was performed and 3D response surfaces were plotted from the mathematical model. According to the RSM model, the highest pectin yield (∼32.3%) can be achieved when the UAE process is carried out at 75°C for 60 min using a citric acid solution of pH 2.0. These pectic polysaccharides, composed mainly by galacturonic acid units (citric acid from grape pomace at industrial level.

  1. Interaction of a dietary fiber (pectin) with gastrointestinal components (bile salts, calcium, and lipase): a calorimetry, electrophoresis, and turbidity study.

    Science.gov (United States)

    Espinal-Ruiz, Mauricio; Parada-Alfonso, Fabián; Restrepo-Sánchez, Luz-Patricia; Narváez-Cuenca, Carlos-Eduardo; McClements, David Julian

    2014-12-31

    An in vitro gastrointestinal model consisting of oral, gastric, and intestinal phases was used to elucidate the impact of pectin on the digestion of emulsified lipids. Pectin reduced the extent of lipid digestion, which was attributed to its binding interactions with specific gastrointestinal components. The interaction of pectin with bile salts, lipase, CaCl2, and NaCl was therefore investigated by turbidity, microstructure, electrophoresis, and isothermal titration calorimetry (ITC) at pH 7.0 and 37 °C. ITC showed that the interaction of pectin was endothermic with bile salts, but exothermic with CaCl2, NaCl, and lipase. Electrophoresis, microstructure, and turbidity measurements showed that anionic pectin formed electrostatic complexes with calcium ions, which may have decreased lipid digestion due to increased lipid flocculation or microgel formation because this would reduce the surface area of lipid exposed to the lipase. This research provides valuable insights into the physicochemical and molecular mechanisms of the interaction of pectin with gastrointestinal components that may affect the rate and extent of lipid digestion.

  2. 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.

  3. 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.

  4. 野菊花乙醚提取物的理化性质及抗氧化能力%Physicochemical Characterization and Antioxidant Activity of Ether Extract from Flos chrysanthemi indici

    Institute of Scientific and Technical Information of China (English)

    申海进; 郭巧生; 房海灵

    2012-01-01

    Physicochemical proprieties and antioxidant activity of ether extract from Flos chrysanthemi indici were investigated in this study.The yield of dried ether extract from crude materials(dry weight) was 2.15%.The content of carotenoids in dried extract was(165.51 ± 1.42) mg/g.The ether extract was added to four kinds of edible oil including peanut oil,soybean oil,sunflower oil and corn oil to evaluate its antioxidant activity.Our results indicated that the ether extract could effectively inhibit lipid oxidation and displayed a potential antioxidant activity in a dose-dependent manner.Therefore,this ether extract may be considered as a potential antioxidant agent.%研究野菊花乙醚提取物的基本理化性质及其抗氧化特性。结果表明:野菊花乙醚提取物中类胡萝卜素含量为(165.51±1.42)mg/g,β-胡萝卜素含量为(2537.96±11.57)μg/g;抗氧化实验显示提取物均能够有效阻止花生油、大豆油、葵花籽油、玉米油的脂质快速氧化,且具有剂量效应关系。野菊花乙醚提取物是一种潜在的油脂氧化保护剂,具备一定的抗氧化能力。

  5. Research progress on chemical constituents and pharmacological activities of Chrysanthemi Flos%杭白菊化学成分和药理活性的研究进展

    Institute of Scientific and Technical Information of China (English)

    钟爱娇; 姜哲; 李雪征; 李宁

    2014-01-01

    杭白菊具有较高的药用价值,民间应用广泛,是卫生部首批批准的药食同源的道地药材之一。杭白菊主要含有黄酮、挥发油、三萜、甾体、酚类、多糖及微量元素等多种成分,具有心血管保护、降血脂、血糖、血压、抗氧化、抗癌、神经保护、肝保护等多种药理活性。为了进一步开发和合理利用该药用植物资源,综述了近年来国内外对杭白菊的化学成分和药理活性的研究进展。%Chrysanthemi Flosis widely used in folk with high medicinal value. It was firstly approved as one of the medicinal and edible herbals by Ministry of Public Health. Phytochemical studies revealed that it contained flavonoids, volatile oils, triterpenes, sterols, phenols, polysaccharides, trace elements and other physiologically active substances. Furthermore, it showed many pharmaceutical effects, such as cardiovascular protective and hypolipidemic, hyperglycemic and hypotesive activities, antioxidative, anti-cancer, neuroprotective effects, hepatoprotective effects, and so on. To further develop and rationally use this plant resource, this article summarizes the chemical constituents and pharmacological activities ofChrysanthemi Flosin recent years.

  6. Solvent-Free Synthesis of Modified Pectin Compounds Promoted by Microwave Irradiation

    Directory of Open Access Journals (Sweden)

    Vittoria Vittoria

    2012-10-01

    Full Text Available Microwave-assisted solvent-free modification of pectin was successfully accomplished, consisting in the esterification of several fatty acids by pectin alcoholic functions. The reaction was performed by simply mixing the reagents with a catalytic amount of the inorganic base (potassium carbonate and irradiating the obtained mixture with microwaves for a short time (3–6 min. The replacement of the traditional heating with a microwave source allowed the development of a new synthetic protocol which provided increased yield of the final products, since it eliminates the small amount of degraded polysaccharide produced during traditional oil bath heating. The desired esters were fully characterized by FT-IR spectroscopy and thermogravimetric analysis.

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

    DEFF Research Database (Denmark)

    Lund, Christian Have

    GALACTURONOSYLTRANSFERASE1 (GAUT1) and GAUT7 has beesn identified and is essential for pectin biosynthesis. Interestingly, GAUT1 has been shown to be proteolytic processed from its transmembrane anchor domain and its catalytic domain is retained by GAUT7, thus ensuring biosynthesis of HG in the Golgi apparatus. Many...... methods exist in identifying protein-protein interaction (PPI) but many of these are developed for other organisms than plants and are most applicable for PPI detection in other organelles than the Golgi apparatus where pectin biosynthesis occurs. In this work, different PPI detection methods are examined...... for their ability to detect PPI inside the Golgi lumen. The first method tested was the commercially available splitubiquitin system from Dualsystems Biotech AG. This was applied to test binary interactions between proteins involved in HG and Rhamnogalacturonan I (RG-I) biosynthesis (see Manuscript II...

  8. Facile synthesis of pectin coated Fe3O4 nanospheres by the sonochemical method

    Science.gov (United States)

    Dai, Junjun; Wu, Shixi; Jiang, Wei; Li, Pingyun; Chen, Xiaolong; Liu, Li; Liu, Jie; Sun, Danping; Chen, Wei; Chen, Binhua; Li, Fengsheng

    2013-04-01

    Pectin coated Fe3O4 magnetic nanospheres (PCMNs) were synthesized by the sonochemical method. The Fe3O4 nanoparticles were prepared by chemical precipitation as reported in the previous articles, and the PCMNs were characterized by transmission electron microscopy, dynamic light scattering, thermogravimetric analysis, Fourier-transform infrared spectroscopy, a vibrating sample magnetometer and energy dispersive X-ray spectrum. The results indicated that the magnetic nanoparticles have been coated by pectin, magnetite content of which was up to 63%, with the saturation magnetization being 32.69 emu/g. The formation mechanism and further application of PCMNs have also been discussed. The results show that the PCMNs can be applied to biomedical applications.

  9. Response surface optimization of ultrasound assisted extraction of pectin from pomegranate peel.

    Science.gov (United States)

    Moorthy, I Ganesh; Maran, J Prakash; Surya, S Muneeswari; Naganyashree, S; Shivamathi, C S

    2015-01-01

    Ultrasound assisted extraction of pectin from waste pomegranate peel was investigated and optimized using Box-Behnken response surface design coupled with numerical optimization technique. The individual and interactive effect of process variables (solid-liquid ratio, pH, extraction time and temperature) on the pectin yield was studied. The experimental data obtained were analyzed by Pareto analysis of variance (ANOVA) and second-order polynomial models were developed using multiple regression analysis. The models developed from the experimental design were predictive and good fit with the experimental data with high coefficient of determination (R(2)) value. The optimal extraction condition was found to be 1:17.52 g/ml of solid-liquid ratio, 1.27 of pH, 28.31 min of extraction time and 61.90 °C of extraction temperature respectively. Under the optimal conditions, experimental yield was very close to the predicted values.

  10. Statistical optimization of aqueous extraction of pectin from waste durian rinds.

    Science.gov (United States)

    Maran, J Prakash

    2015-02-01

    The objectives of this present study was to investigate and optimize the aqueous extraction conditions such as solid-liquid (SL) ratio (1:5-1:15 g/ml), pH (2-3), extraction time (20-60 min) and extraction temperature (75-95 °C) on maximum extraction of pectin from durian rinds using four factors, three levels Box-Behnken response design. The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis and analyzed by analysis of variance (ANOVA). The optimum extraction condition was found to be as follows: SL ratio of 1:10 g/ml, pH of 2.8, extraction time of 43 min and extraction temperature of 86 °C respectively. Under the optimal conditions, the experimental pectin yield (9.1%) was well correlated with predicted yield (9.3%).

  11. Studies on alpha-amylase induced degradation of binary polymeric blends of crosslinked starch and pectin.

    Science.gov (United States)

    Bajpai, A K; Shrivastava, Jyoti

    2007-05-01

    A blend matrix of crosslinked starch and pectin was prepared and characterized by infra-red (IR) spectroscopy, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). The prepared blends were investigated kinetically for water sorption studies and alpha-amylase induced degradation adopting a gravimetric procedure. Based on the experimental findings, a plausible mechanism including both diffusion and surface enhanced degradation was suggested and degradation profiles were interpreted. The influence of various factors such as chemical architecture of the blend, pH and temperature of alpha-amylase solution were examined for the swelling and degradation kinetics of crosslinked starch-pectin blends. The effect of concentration of enzyme solution was also studied on the degradation profile of the blends. A correlation was established between the extent of degradation and water imbibing capacity of the degrading blends.

  12. [Late hypoglycaemia in chemical diabetes. Abnormalities of pancreatic glucagon secretion and effect of pectine (author's transl)].

    Science.gov (United States)

    Mirouze, J; Orsetti, A; Monnier, L; Bringer, J; Pham, T C

    1979-12-01

    Nineteen patients suffering from chemical diabetes either with (group A, ten cases) or without (group B, nine cases) reactive hypoglycaemia were included in the study and compared with seven control (group C). The following variables were measured over a 5 hour period during a standard oral glucose tolerance test (OGTT): (i) blood glucose by continuous monitoring; (ii) plasma insulin and glucagon levels by radioimmunoassay. Furthermore, in five diabetics of group A, the data from the standard OGTT were compared with those from a pectin-supplemented OGTT (9 g per square meter of body surface). Although the insulin response was similar glucagon levels were significantly higher (45.1 +/- 11.8 pmol/l) (p less than 0.01) in group B than in group A (9.6 +/- 1.3) and C (8.1 +/- 1.4 at 30 minutes). The high glucagon levels noted in group B may explain the absence of reactive hypoglycaemia. The pectin supplementation improved the OGTT pattern by blunting the blood glucose peak (p less than 0.05), and avoiding the reactive hypoglycaemia (p less than 0.01). The addition of pectin did not produce any significant effect on the insulin response while a significant increase in glucagon concentrations (p less than 0.05) was observed beyond the 150th minute. Therefore, the data suggest that pectin may improve the OGTT pattern by increasing the glucagon response in the late period of the test. The development of postprandial reactive hypoglycaemia seldom coincides with a plasma glucagon peak, while the absence of reactive hypoglycaemia tends to be associated with high levels of glucagon, as is the case in overt diabetes mellitus.

  13. Research of frequency descriptions, parameters conductometric differential sensors with pectinate topology.

    OpenAIRE

    2011-01-01

    In differential conductometric systems, for example in biosensor systems, often use co-planar thinly-pellicle structure double-sensors with pectinate topology. Simple and useful devices could be realized with help of them. But sensitivity and producibility of results those devices depends on parameters of sensors which we probe. On base of metrological research frequency descriptions, parameters conductometric differential sensors was analyzed effectiveness of using this sensors with differen...

  14. 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)

  15. Pectin lyase overproduction by Penicillium griseoroseum mutants resistant to catabolite repression.

    Science.gov (United States)

    Lima, Juliana Oliveira; Pereira, Jorge Fernando; Araújo, Elza Fernandes de; Queiroz, Marisa Vieira de

    2017-02-09

    Expression of pectinolytic genes is regulated by catabolic repression limiting the production of pectin lyase (PL) if the natural inducer, pectin, is missing from the growth medium. Here, we report the isolation of Penicillium griseoroseum mutants resistant to 2-deoxy-d-glucose (DG) that show resistance to catabolite repression and overproduce PL. Three spontaneous and nine UV-induced mutants were obtained. Some mutants produced sectors (segments morphologically different) that were also studied. The mutants were analyzed for pectinases production on pectinase-agar plates and five mutants and two sectors showing larger clearing zones than the wild type were selected for quantitative assay. Although PL production higher than the wild type has been found, phenotype instability was observed for most of the mutants and, after transfers to nonselective medium, the DG resistance was no longer present. Only mutants M03 and M04 were stable maintaining the DG-resistance phenotype. When growing for 120h in liquid medium containing glucose with or without pectin, both mutants showed higher PL production. In the presence of glucose as sole carbon source, the mutant M03 produced 7.8-fold more PL than the wild type. Due its phenotypic stability and PL overproduction, the mutant M03 presents potential for industrial applications.

  16. Characterization of Two Homogalacturonan Pectins with Immunomodulatory Activity from Green Tea

    Directory of Open Access Journals (Sweden)

    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.

  17. Development of calcium pectinate-tamarind seed polysaccharide mucoadhesive beads containing metformin HCl.

    Science.gov (United States)

    Nayak, Amit Kumar; Pal, Dilipkumar; Santra, Kousik

    2014-01-30

    Novel mucoadhesive beads containing metformin HCl made of low methoxy (LM) pectin-tamarind seed polysaccharide (TSP) polymer-blend was developed through ionotropic-gelation technique and optimized using 3(2) factorial design. Effects of LM pectin and TSP amounts on drug encapsulation efficiency (DEE), and cumulative drug release at 10h (R10h) were analyzed using response surface methodology. The optimized calcium pectinate-TSP beads containing metformin HCl showed DEE of 95.12 ± 4.26%, R10h of 46.53 ± 3.28%, and mean diameter of 1.93 ± 0.26 mm. The in vitro drug release from these beads was followed controlled-release (zero-order) pattern with super case-II transport mechanism. These beads were also characterized by SEM and FTIR. The optimized beads also exhibited pH-dependent swelling, good mucoadhesivity with goat intestinal mucosa and significant hypoglycemic effect in alloxan-induced diabetic rats over prolonged period after oral administration.

  18. Biodegradable IPN hydrogel beads of pectin and grafted alginate for controlled delivery of diclofenac sodium.

    Science.gov (United States)

    Giri, Tapan Kumar; Thakur, Deepa; Alexander, Amit; Ajazuddin; Badwaik, Hemant; Tripathy, Minaketan; Tripathi, Dulal Krishna

    2013-05-01

    A novel diclofenac sodium (DS) loaded interpenetrating polymer network (IPN) beads of pectin and hydrolyzed polyacrylamide-graft-sodium alginate (PAAm-g-SA) was developed through ionotropic gelation and covalent cross-linking. The graft copolymer was synthesized by free radical polymerization under the nitrogen atmosphere followed by alkaline hydrolysis. The grafting, alkaline hydrolysis, and characterization of beads were confirmed by Fourier transforms infrared spectroscopy. The crystalline structure of drug after encapsulation into IPN beads were evaluated by differential scanning colorimetry and X-ray diffraction analyses. DS encapsulation was up to 96.45 %. The effect of hydrolyzed graft copolymer/pectin ratios and glutaraldehyde concentration on drug release in acidic and phosphate buffer solutions were investigated. The release of drug was significantly increased with increase of pH. The release of drug depends on the extent of cross-linking. The results indicated that IPN beads of hydrolyzed PAAm-g-SA and pectin could be used for sustained release of DS.

  19. Investigation of Pectin/Chitosan Multilayers Build-up on Corona Charged Polylactide Substrates

    Science.gov (United States)

    Yovcheva, T. A.; Marudova, M. G.; Viraneva, A. P.; Gencheva, E. A.; Mekishev, G. A.; Sainov, S. H.

    2010-01-01

    The aim of the present research is to investigate the formation and stability of pectin/chitosan multilayer films on preliminary corona charged polylactide substrate with different polarity. For this purpose two different multilayer structures with alternative ordering of polycation and polyanion layers were prepared. Layer-by-layer (LbL) deposition technique was used for multilayer build-up. The FT-IR transmittance spectra of the substrates with multilayers indicated of the presence of pectin and chitosan. The intensity of the typical bands was found to increase with increasing of the number of the deposited layers. The stability and physico-chemical properties of the multilayer structures were investigated by determination of surface refractive index and swelling behaviour. Multilayers are stable enough in distilled water and their equilibrium degree of swelling increases with the increase of build-up layers. This relation is correlated with the increased amount of hydrophilic biopolymers. It was found out that chitosan/pectin multilayers buil-up on negatively charged substrate consist of higher amount of polyelectrolytes and are more stable in distilled water.

  20. Yield of albedo flour and pectin content in the rind of yellow passion fruit

    Directory of Open Access Journals (Sweden)

    Eliana Monteiro Soares de Oliveira

    2012-09-01

    Full Text Available In this study, it was evaluated the influence of different shapes, sizes, and maturation stages on the yield of albedo flour and pectin content of yellow passion fruit rinds. Random samples of 40 fruits were used, and the data were compared using significance intervals at 5%. Weight, skin color, fruit size and shape, pulp yield, mesocarp thickness, amount of epicarp and mesocarp, moisture content, and pectin yield were determined. The maturation stages were defined according to measurements of the yellow color of the skin. The shape and size patterns were defined according to the length/width ratio (equatorial diameter of fruits. It was found that the epicarp thickness was not correlated to fruit shape and size, but it was thicker in ripe fruits. The mesocarp was thiner in small ripe fruits, but it did not change with fruit shape. Pulp yield was higher in ripe fruits, and it was not influenced by shape and size of fruits. It was concluded that the content of albedo flour can account for 3.9% of the weight of processed fruits, whereas the amount of pectin powder can account for up to 0.9% of the fruit weight.

  1. In Vitro and In Vivo Evaluation of Pectin/Copper Exchanged Faujasite Composite Membranes.

    Science.gov (United States)

    Ninan, Neethu; Muthiah, Muthunarayanan; Park, In-Kyu; Elain, Anne; Wong, Tin Wui; Thomas, Sabu; Grohens, Yves

    2015-09-01

    The biocompatibility and excellent ion exchange capacity make faujasites ideal candidates for tissue engineering applications. A novel pectin/copper exchanged faujasite hybrid membrane was synthesized by solvent casting technique, using calcium chloride as the crosslinking agent. AFM images revealed the egg-box model organization of calcium cross-linked pectin chains used as a matrix. The morphology of composite membranes was characterized by SEM and their elemental composition was determined using EDX. The higher contact angle of P (1%) when compared to that of native pectin figured out an enhanced hydrophobicity of hybrid material. The embedded faujasite particles maintained their crystalline structure as revealed by XRD and their interactions with the polymer matrix was evaluated by FTIR. The composite membrane with 1% (w/w) of copper exchanged faujasite, P(1%), exhibited better thermal stability, excellent antibacterial activity, controlled swelling and degradation. Finally, it displayed cell viability of 89% on NIH3T3 fibroblast cell lines and aided in improving wound healing and re-epithelialisation in Sprague Dawley rats. The obtained data suggested their potential as ideal matrices for efficient treatment of burn wounds.

  2. 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

  3. Structure formation in sugar containing pectin gels - influence of tartaric acid content (pH) and cooling rate on the gelation of high-methoxylated pectin.

    Science.gov (United States)

    Kastner, H; Kern, K; Wilde, R; Berthold, A; Einhorn-Stoll, U; Drusch, S

    2014-02-01

    The aim of the study was the application of a recently published method, using structuring parameters calculated from dG'/dt, for the characterisation of the pectin sugar acid gelation process. The influence of cooling rate and pH on structure formation of HM pectin gels containing 65 wt.% sucrose were investigated. The results show that the structure formation process as well as the properties of the final gels strongly depended on both parameters. With increasing cooling rates from 0.5 to 1.0 K/min the initial structuring temperature slightly decreased and the maximum structuring velocity increased. The lower the cooling rates, the firmer and more elastic were the final gels. With increasing acid content (decreasing pH from 2.5-2.0) the initial structuring temperatures were nearly constant. The final gel properties varied visibly but not systematically. Gels with the lowest and highest pH were less elastic and weaker compared to those with medium acid concentrations.

  4. Extraction and camparison of amount of pectin, degree of estrification and galacturonic acidcontent in some citrus fruit peels

    Directory of Open Access Journals (Sweden)

    M.A. Ebrahimzadeh

    2006-01-01

    Full Text Available Background and purpose: Pectin is widely used in food, cosmetic and drug industries. Because of high production and consumption of citrus fruits in Mazandaran, fruit peel is available in large quantities. The objective of the current investigation was to determine the amount of pectin, degree of estrification, a key factor in rheological properties of pectin, and galacturonic acid content as a criterion for pectin purity.Materials and Methods: Thirteen species of commonly used citrus fruits, orange cultivates (Citrus sinensis; Washington navel, Sanguinello, Valencia, Acidless, Moro, Shahsavari, Italian orange, Clementine, Unshiu, Grapefruit (C. paradisi, Bitter (sour orange (C. aurantium, Lemon (C. limon and Tangelo were collected at the ripening stage. All the trees were cultivated in the experimental fields, Fajr citrus experimental institute. Amount of pectin was determined by acidic extraction from dry albedos of fruits. Degree of estrification and galacturonic acid content were determined by USP standard titrimetric procedure.Results: The highest amount of pectin was found in Italian orange (27%, Shahsavari orange (25% and Sanguinello (20 % on the basis of dry weight. The highest degree of estrification (11.5% , 10.9% and 9.6% was found in Lemon, Washington navel and Bitter (sour orange respectively. The highest galacturonic acid contents were found in Washington navel, Lemon and Italian orange (89.3, 85.4 and 77.7 respectively.Conclusion: Six fruits were suitable for utilization in drug industries including: Washington navel, Acidless, Shahsavari, Italian orange, Bitter (sour orange (C. aurantium, Lemon (C. limon. Washington navel and Lemon had the most suitable pectin for pharmaceutical purposes

  5. 橘皮果胶的提取及果胶膜制备工艺参数的优化%Optimization of Process Parameters on Pectin Extraction from Orange Peel and Preparation of Pectin Film

    Institute of Scientific and Technical Information of China (English)

    许茹; 武文洁; 南岳

    2011-01-01

    采用3种不同的方法从橘皮中提取果胶,探讨果胶膜成膜因素对制备膜性能的影响,研究制备膜的最佳工艺.结果表明:酒石酸酸解盐析法提取果胶效果最好,提取率达10.35%;果胶质量分数、变性淀粉质量分数及助膜剂质量分数均影响制备果胶膜的抗拉强度;影响制备果胶膜抗拉强度的主要因素顺序为助膜剂质量分数>果胶质量分数>变性淀粉质量分数,果胶质量分数2.5%、助膜剂质量分数3.0%、变性淀粉质量分数10.0%为制备膜的最佳工艺条件.%Pectin was extracted from orange peel by three different methods.The effects of pectin concentration,glycerol concentration and modified starch on the properties of pectin film were investigated and optimal process was studied.The results showed that the total pectin extraction efficiency is 10.35% by the tartaric acid hydrolysis and salting-out method.Finally,the results indicate the effects of glycerol concentration ,pectin concentration,and modified starch addition on intensity of tension of the pectin film is significant.The main sequence of the factors affecting tensile strength of pectin film is as follows:glycerol concentration>pectin concentration>modified starch addition.The optimum concentrations of pectin,glycerol and modified starch are 2.5%,3.0% and 10.0%,respectively.

  6. An in situ crosslinked compression coat comprised of pectin and calcium chloride for colon-specific delivery of indomethacin.

    Science.gov (United States)

    Wei, Xiuli; Lu, Yi; Qi, Jianping; Wu, Baojian; Chen, Jian; Xu, Huinan; Wu, Wei

    2015-05-01

    The use of pectin for colon-specific drug delivery has been extensively investigated; however, when used alone, pectin is often compromised due to its high solubility. This study explored the feasibility of using an in situ compression-coated crosslinking system, composed of pectin and calcium chloride, for colon-specific drug delivery. A pectin/calcium chloride (P/Ca) coating was compressed onto a core tablet. The colon specificity of the compression-coated tablet was verified by dissolution, pharmacokinetics and scintigraphy with (99m)Tc labeling. The in situ pectin and calcium chloride gel slowed the release of indomethacin. The lag time varied between 3 h and 7 h depending on the amount of calcium chloride and the coating weight. Pectinase triggered the release of indomethacin from the compression-coated tablet, which was then accelerated by the calcium chloride in the coating layer. The compression-coated tablet had a prolonged tmax and apparent t1/2, as well as a decreased Cmax and AUC0-t, compared with the core tablet counterpart. Evaluation with γ-scintigraphy verified colon-specific delivery of the compression-coated tablet. In conclusion, the P/Ca in situ crosslinking system worked well for colon-specific drug delivery.

  7. The Development, Physicochemical Characterisation and in Vitro Drug Release Studies of Pectinate Gel Beads Containing Thai Mango Seed Kernel Extract

    Directory of Open Access Journals (Sweden)

    Hatem Fessi

    2013-06-01

    Full Text Available Pectinate gel beads containing Thai mango seed kernel extract (MSKE, cultivar ‘Fahlun’ were developed and characterised for the purpose of colon-targeted delivery. The MSKE-loaded pectinate beads were prepared using ionotropic gelation with varying pectin-to-MSKE ratios, MSKE concentrations, and concentrations of two cross-linkers (calcium chloride and zinc acetate. The formulated beads were spherical in shape and ranged in size between 1.13 mm and 1.88 mm. Zinc-pectinate (ZPG beads containing high amounts of MSKE showed complete entrapment efficiency (EE of MSKE (100%, while calcium-pectinate (CPG beads demonstrated 70% EE. The in vitro release tests indicated that MSKE-loaded CPG beads were unstable in both simulated gastric medium (SGM and simulated intestinal medium (SIM, while MSKE-loaded ZPG beads were stable in SIM but unable to prevent the release of MSKE in SGM. The protection of ZPG beads with gastro-resistant capsules (Eudragit® L 100-55 resulted in stability in both SGM and SIM; they disintegrated immediately in simulated colonic medium containing pectinolytic enzymes. MSKE-loaded ZPG beads were stable at 4, 25 and 45 °C during the study period of four months. The present study revealed that ZPG beads in enteric-coated capsules might be a promising carrier for delivering MSKE to the colon.

  8. Pectin-chitosan-PVA nanofibrous scaffold made by electrospinning and its potential use as a skin tissue scaffold.

    Science.gov (United States)

    Lin, Hsin-Yi; Chen, Hsin-Hung; Chang, Shih-Hsin; Ni, Tsung-Sheng

    2013-01-01

    Scaffolds made of chitosan nanofibers are often too mechanically weak for their application and often their manufacturing processes involve the use of harmful and flammable organic solvents. In the attempt to improve the mechanical properties of nanofibrous scaffolds made of chitosan without the use of harmful chemicals, pectin, an anionic polymer was blended with chitosan, a cationic polymer, to form a polyelectrolyte complex and electrospun into nanofibers for the first time. The electrospun chitosan-pectin scaffolds, when compared to electrospun chitosan scaffolds, had a 58% larger diameter, a 21% higher Young's modulus, a 162% larger strain at break, and a 104% higher ultimate tensile strength. Compared to the chitosan scaffolds, the chitosan-pectin scaffolds' swelling ratios decreased by 55% after 60 min in a saline solution and more quickly released the preloaded tetracycline HCl. The L929 fibroblast cells proliferated slightly slower on the chitosan-pectin scaffolds than on the chitosan scaffolds. Nonetheless, cells on both materials deposited similar levels of extracellular type I collagen on a per DNA basis. In conclusion, a novel chitosan-pectin nanofibrous scaffold with superior mechanical properties than a chitosan nanofibrous scaffold was successfully made without the use of harmful solvents.

  9. Chemical Composition, Functional Properties, and Effect of Inulin from Tunisian Agave americana L. Leaves on Textural Qualities of Pectin Gel

    Directory of Open Access Journals (Sweden)

    Mohamed Ali Bouaziz

    2014-01-01

    Full Text Available In this study, the chemical composition and functional properties of Agave americana L. (AA leaves were determined. The Agave leaves powder had a high amount of total dietary fiber (38.40%, total sugars (45.83%, and protein (35.33%, with a relatively low content in ash (5.94% and lipid (2.03%. The Agave leaves were exhibited with potential food application. The Agave inulin showed a significant difference compared with the commercial inulin as for aw (0.275 against 0.282, pH (5.53 against 5.98, ash (2.89% against 1.19%, protein (3.46% against 1.58%, water holding capacity (2.42% against 1.59%, solubility (73 g/L against 113 g/L, and emulsion capacity (14.48% against 21.42%, respectively. The textural properties of Agave inulin-pectin mixed gels were examined using instrumental Texture Profile Analysis (TPA. Firmness of the prepared Agave inulin-pectin mixed gels was lower than the pectin gel (0.3554 N against 5.7238 N, resp.. This reduction of firmness showed a synergetic effect between pectin and inulin. These results suggested a positive interaction between Agave inulin and pectin to decrease the firmness of mixed gels and open a good alternative to obtain value added products from this resource.

  10. The development, physicochemical characterisation and in vitro drug release studies of pectinate gel beads containing Thai mango seed kernel extract.

    Science.gov (United States)

    Nithitanakool, Saruth; Pithayanukul, Pimolpan; Bourgeois, Sandrine; Fessi, Hatem; Bavovada, Rapepol

    2013-06-03

    Pectinate gel beads containing Thai mango seed kernel extract (MSKE, cultivar 'Fahlun') were developed and characterised for the purpose of colon-targeted delivery. The MSKE-loaded pectinate beads were prepared using ionotropic gelation with varying pectin-to-MSKE ratios, MSKE concentrations, and concentrations of two cross-linkers (calcium chloride and zinc acetate). The formulated beads were spherical in shape and ranged in size between 1.13 mm and 1.88 mm. Zinc-pectinate (ZPG) beads containing high amounts of MSKE showed complete entrapment efficiency (EE) of MSKE (100%), while calcium-pectinate (CPG) beads demonstrated 70% EE. The in vitro release tests indicated that MSKE-loaded CPG beads were unstable in both simulated gastric medium (SGM) and simulated intestinal medium (SIM), while MSKE-loaded ZPG beads were stable in SIM but unable to prevent the release of MSKE in SGM. The protection of ZPG beads with gastro-resistant capsules (Eudragit® L 100-55) resulted in stability in both SGM and SIM; they disintegrated immediately in simulated colonic medium containing pectinolytic enzymes. MSKE-loaded ZPG beads were stable at 4, 25 and 45 °C during the study period of four months. The present study revealed that ZPG beads in enteric-coated capsules might be a promising carrier for delivering MSKE to the colon.

  11. 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.

  12. 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 hydrop...

  13. 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...

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

    Directory of Open Access Journals (Sweden)

    G.P. Ganda-Putra

    2010-08-01

    Full Text Available 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 of cocoa beans produced and to study the role of those fermentation process in reducing fermentation time to produce cocoa beans with standard quality. This research used split plot design, with treatments of process condition of cocoa fermentation as main plot and fermentation period as split plot. Treatment of process condition of cocoa fermentation consisted of optimum condition for pulp pectin depolymerization by PGs (temperature 47.5OC; initial pulp pH 4.6; optimum condition of depolymerization on sequence depolymerization by PGs (temperature 48.5OC; initial pulp pH 8.0 during 1 day; last temperature 47.5OC; initial pulp pH 4.6 during 6 days, and natural fermentation process a control. While treatment of fermentation period consisted of 0, 1, 2, 3, 4, 5, 6 and 7 days. Evaluation of fermentation period was carried out based on pursuant to criteria of unfermented beans content and fermentation index. The results showed that process condition and fermentation time of cocoa affected quality characteristic of cocoa beans produced. Period of cocoa fermentation process based on optimum condition for pulp pectin depolymerization using endogenous pectolytic enzymes was 2 days shorter compared to natural fermentation. Cocoa beans quality of grade I and II were obtained from fermentation time of 4 and 2 days, respectively, using fermentation process based on optimum condition of pulp pectin depolymerization using endogenous pectolytic enzymes, whereas 6 and 4 days

  15. 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.

    Science.gov (United States)

    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.

  16. Colour and stability assessment of blue ferric anthocyanin chelates in liquid pectin-stabilised model systems.

    Science.gov (United States)

    Buchweitz, M; Brauch, J; Carle, R; Kammerer, D R

    2013-06-01

    The formation of blue coloured ferric anthocyanin chelates and their colour stability during storage and thermal treatment were monitored in a pH range relevant to food (3.6-5.0). Liquid model systems were composed of different types of Citrus pectins, juices (J) and the respective phenolic extracts (E) from elderberry (EB), black currant (BC), red cabbage (RC) and purple carrot (PC) in the presence of ferric ions. For EB, BC and PC, pure blue colours devoid of a violet tint were exclusively observed for the phenolic extracts and at pH values ≥ 4.5 in model systems containing high methoxylated and amidated pectins, respectively. Colour and its stability strongly depended on the amount of ferric ions and the plant source; however, colour decay could generally be described as a pseudo-first-order kinetics. Despite optimal colour hues for RC-E and RC-J, storage and heat stabilities were poor. Highest colour intensities and best stabilities were observed for model systems containing PC-E at a molar anthocyanin:ferric ion ratio of 1:2. Ascorbic and lactic acids interfered with ferric ions, thus significantly affecting blue colour evolution and stability. Colour loss strongly depended on heat exposure with activation energies ranging between 60.5 and 78.4 kJ/mol. The comprehensive evaluation of the interrelationship of pigment source, pH conditions and pectin type on chelate formation and stability demonstrated that ferric anthocyanin chelates are promising natural blue food colourants.

  17. 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.

  18. 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.

  19. Effect of Drug Loading Method on Drug Content and Drug Release from Calcium Pectinate Gel Beads

    OpenAIRE

    2010-01-01

    Drug-loaded calcium pectinate gel (CaPG) beads were prepared by either mixing, absorption, or swelling method. The effects of drug loading method as well as the drug loading factors (i.e., drug concentration, soaking time in drug solution, type of solvent) on drug content and drug release were investigated. The amount of drug uptake (i.e., drug content) into CaPG beads increased as the initial drug concentration increased and varied depending on the loading method. The in vitro release studie...

  20. Crystallization and preliminary X-ray analysis of pectin lyase A from Aspergillus niger.

    Science.gov (United States)

    Jenkins, J; Scott, M; Mayans, O; Pickersgill, R; Harris, G; Connerton, I; Gravesen, T

    1996-03-01

    The major secreted pectin lyase (E.C. 4.2.2.10) from Aspergillus niger, strain 4M-147, has been purified and crystallized by the hanging-drop method using polyethylene glycol as precipitant. The crystals belong to the space group P2(1)2(1)2(1) with cell dimensions a = 45.2, b = 83.2, c = 93.1 A (1 A = 0.1 nm) and a single molecule in the asymmetric unit. The crystals diffract to at least 2.0 A resolution and are suitable for structure determination.

  1. Nanocoating with plant-derived pectins activates osteoblast response in vitro

    Science.gov (United States)

    Folkert, J; Meresta, A; Gaber, T; Miksch, K; Buttgereit, F; Detert, J; Pischon, N; Gurzawska, K

    2017-01-01

    A new strategy to improve osseointegration of implants is to stimulate adhesion of bone cells, bone matrix formation, and mineralization at the implant surface by modifying surface coating on the nanoscale level. Plant-derived pectins have been proposed as potential candidates for surface nanocoating of orthopedic and dental titanium implants due to 1) their osteogenic stimulation of osteoblasts to mineralize and 2) their ability to control pectin structural changes. The aim of this study was to evaluate in vitro the impact of the nanoscale plant-derived pectin Rhamnogalacturonan-I (RG-I) from potato on the osteogenic response of murine osteoblasts. RG-I from potato pulps was isolated, structurally modified, or left unmodified. Tissue culture plates were either coated with modified RG-I or unmodified RG-I or – as a control – left uncoated. The effect of nanocoating on mice osteoblast-like cells MC3T3-E1 and primary murine osteoblast with regard to proliferation, osteogenic response in terms of mineralization, and gene expression of Runt-related transcription factor 2 (Runx2), alkaline phosphate (Alpl), osteocalcin (Bglap), α-1 type I collagen (Col1a1), and receptor activator of NF-κB ligand (Rankl) were analyzed after 3, 7, 14, and 21 days, respectively. Nanocoating with pectin RG-Is increased proliferation and mineralization of MC3T3-E1 and primary osteoblast as compared to osteoblasts cultured without nanocoating. Moreover, osteogenic transcriptional response of osteoblasts was induced by nanocoating in terms of gene induction of Runx2, Alpl, Bglap, and Col1a1 in a time-dependent manner – of note – to the highest extent under the PA-coating condition. In contrast, Rankl expression was initially reduced by nanocoating in MC3T3-E1 or remained unaltered in primary osteoblast as compared to the uncoated controls. Our results showed that nanocoating of implants with modified RG-I beneficially 1) supports osteogenesis, 2) has the capacity to improve

  2. Research of frequency descriptions, parameters conductometric differential sensors with pectinate topology.

    Directory of Open Access Journals (Sweden)

    D. A. Makarov

    2011-06-01

    Full Text Available In differential conductometric systems, for example in biosensor systems, often use co-planar thinly-pellicle structure double-sensors with pectinate topology. Simple and useful devices could be realized with help of them. But sensitivity and producibility of results those devices depends on parameters of sensors which we probe. On base of metrological research frequency descriptions, parameters conductometric differential sensors was analyzed effectiveness of using this sensors with different geometrical parameters and materials for better descriptions of biosensor system with them.

  3. Fractionation, solid-phase immobilization and chemical degradation of long pectin oligogalacturonides. Initial steps towards sequencing of oligosaccharides

    DEFF Research Database (Denmark)

    Guillaumie, Fanny; Justesen, Sune Frederik Lamdahl; Mutenda, K.E.

    2006-01-01

    This work presents the optimized separation of pectin oligomers, their analysis by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), their subsequent immobilization to supports, and our initial steps towards solid-support assisted sequencing. The ambient...... pressure strong anion-exchange resin Source 15Q combined with ammonium formate buffer (AF) was used for the separation of unsaturated and saturated pectic oligogalacturonides (OGAs) derived from enzymatic digestion of pectin. Routinely, multi-milligram quantities of defined sizes OGAs with DPs from 5 to 19...

  4. Fractionation, solid-phase immobilization and chemical degradation of long pectin oligogalacturonides. Initial steps towards sequencin of oligosaccharides

    DEFF Research Database (Denmark)

    Guillaumie, Fanny; Justesen, Sune F. L.; Mutenda, Kudzai E.

    2006-01-01

    This work presents the optimized separation of pectin oligomers, their analysis by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), their subsequent immobilization to supports, and our initial steps towards solid-support assisted sequencing. The ambient...... pressure strong anion-exchange resin Source 15Q combined with ammonium formate buffer (AF) was used for the separation of unsaturated and saturated pectic oligogalacturonides (OGAs) derived from enzymatic digestion of pectin. Routinely, multi-milligram quantities of defined sizes OGAs with DPs from 5 to 19...

  5. 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

  6. Erwinia chrysanthemi分离株CSCL006 hrpN基因的克隆与高效表达%Molecular Characterization and Overexpression of Erwinia chrysanthemi Strain CSCL006 hrpNCSCL006 Gene, which Encodes An Elicitor of the Hyperdensitive Reaction

    Institute of Scientific and Technical Information of China (English)

    汤承; 崔亚亚; 吴伯骥; 李名扬

    2006-01-01

    通过构建Erwinia chrysanthemi分离株CSCL006的DNA文库,克隆出hrpN CSCL006基因,测序结果显示该基因编码区长1 020 bp;推导的harpinCSCL006与Erwinia chrysanthemi ECl6和3937编码的harpin蛋白同源性高,但与其它软腐菌的harpin蛋白同源性较低;在大肠杆菌中(Escherichia coli)高效表达了hrpN CSCL006基因,重组harpinCSCL006蛋白分子量为34kD.以抗harpinEOC的抗体为探针,Western blot证实该蛋白确为harpin;纯化的harpinCSCL006,能引起烟叶的过敏反应.

  7. 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.

  8. Use of pectin-thorium (IV) tungstomolybdate nanocomposite for photocatalytic degradation of methylene blue.

    Science.gov (United States)

    Gupta, Vinod Kumar; Agarwal, Shilpi; Pathania, Deepak; Kothiyal, N C; Sharma, Gaurav

    2013-07-01

    Pectin-thorium (IV) tungstomolybdate (Pc/TWM) nanocomposite was prepared by mixing biopolymer pectin with its inorganic counterpart thorium (IV) tungstomolybdate (TWM) using the sol-gel method. The nanocomposite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). Distribution coefficient, thermal stability, pH titrations, elution and concentration behaviour were investigated to explore the ion exchange behaviour of nanocomposite material. Pc/TWM exhibited higher ion exchange capacity (1.10 mequiv/g) than its inorganic counterpart (0.62 mequiv/g). The Pc/TWM nanocomposite ion exchanger was thermally stable as it retained 59% of its ion exchange capacity upto 400°C. The pH titrations study revealed the bifunctional nature of Pc/TWM. In order to explore the environmental applicability of the Pc/TWM nanocomposite material, its antibacterial and photocatalytic activities was investigated. 76% of methylene blue dye was photocatalytically degraded after five hours exposure. It also totally inhibited Escherichia coli at 400 μg/ml concentration of Pc/TWM nanocomposite.

  9. Formulation, Evaluation and Optimization of Pectin- Bora Rice Beads for Colon Targeted Drug Delivery System

    Directory of Open Access Journals (Sweden)

    Kuldeep Hemraj Ramteke

    2014-03-01

    Full Text Available Purpose: The purpose of this research was to established new polysaccharide for the colon targeted drug delivery system, its formulation and in vitro and in vivo evaluation. Methods: Microspheres containing pectin and bora rice were prepared by ionotropic gelation technique using zinc acetate as cross linking agent and model drug used was glipizide. A 32 full factorial design was employed to study the effect of independent variables, polymer to drug ratio (A, and concentration of cross linking agent (B on dependent variables, particle size, swelling index, drug entrapment efficiency and percentage drug release. Results: Results of trial batches indicated that polymer to drug ratio and concentration of cross linking agent affects characteristics of beads. Beads were discrete, spherical and free flowing. Beads exhibited small particle size and showed higher percentage of drug entrapment efficiency. The optimized batch P2 exhibited satisfactory drug entrapment efficiency 68% and drug release was also controlled for more than 24 hours. The polymer to drug ratio had a more significant effect on the dependent variables. In vivo gamma scintigraphy study of optimized pectin-bora rice beads demonstrated degradation of beads whenever they reached to the colon. Conclusion: Bora rice is potential polysaccharide for colon targeted drug delivery system.

  10. Eudragit S100 Coated Citrus Pectin Nanoparticles for Colon Targeting of 5-Fluorouracil

    Directory of Open Access Journals (Sweden)

    M. Biswaranjan Subudhi

    2015-02-01

    Full Text Available In the present study, Eudragit S100 coated Citrus Pectin Nanoparticles (E-CPNs were prepared for the colon targeting of 5-Fluorouracil (5-FU. Citrus pectin also acts as a ligand for galectin-3 receptors that are over expressed on colorectal cancer cells. Nanoparticles (CPNs and E-CPNs were characterized for various physical parameters such as particle size, size distribution, and shape etc. In vitro drug release studies revealed selective drug release in the colonic region in the case of E-CPNs of more than 70% after 24 h. In vitro cytoxicity assay (Sulphorhodamine B assay was performed against HT-29 cancer cells and exhibited 1.5 fold greater cytotoxicity potential of nanoparticles compared to 5-FU solution. In vivo data clearly depicted that Eudragit S100 successfully guarded nanoparticles to reach the colonic region wherein nanoparticles were taken up and showed drug release for an extended period of time. Therefore, a multifaceted strategy is introduced here in terms of receptor mediated uptake and pH-dependent release using E-CPNs for effective chemotherapy of colorectal cancer with uncompromised safety and efficacy.

  11. DESIGN AND EVALUATION OF PECTIN BASED MATRIX FOR TRANSDERMAL PATCHES OF MELOXICAM

    Directory of Open Access Journals (Sweden)

    PALLAVI SRIVASTAVA, G.T.KULKARNI, MANISH KUMAR, SHARAD VISHT

    2013-09-01

    Full Text Available Transdermal drug delivery system was developedusing meloxicam as a model drug. Meloxicam is anon steroidal anti-inflammatory (NSAID drug.The suitability of drug with respect to solubility,lower molecular weight and short half life makesthis drug as a suitable candidate for administrationby transdermal route. The polymer selected for thestudy is pectin. The polymer is non-toxic andbiodegradable in nature. In the presentinvestigation various concentration ratios ofpolymer were used for the fabrication of the matrixdiffusion controlled transdermal drug deliverysystem by solvent evaporation technique. Thesetransdermal drug delivery systems werecharacterized for their thickness, weight variation,folding endurance, swelling index, contentuniformity, compatibility, in-vitro release and skinirritation studies of the drug from the polymericmatrix. Meloxicam was found to be compatiblewith pectin as revealed by Fourier TransformInfrared Spectroscopy (FTIR studies and showedsatisfactory physiochemical characteristics. In-vitrorelease studies were carried out with modifiedFranz diffusion cell using pH 7.4 phosphate bufferas receptor medium and it showed controlledrelease of drug. Thus the prepared transdermalfilms can be used to achieve controlled release andimproved bioavailability of meloxicam.

  12. Utilization of cast seaweed and waste from pectin production for anaerobic digestion

    DEFF Research Database (Denmark)

    Fredenslund, Anders Michael; Christensen, Thomas Budde; Kjær, Tyge

    2011-01-01

    The paper describes a preliminary study on the environmental consequences of realizing a biogas plant using locally available biomass fractions in Solrød, Denmark. The biomass, which will be used at the plant, will consist of: cast seaweed (app. 20,000 tons year-1), waste from pectin production...... (app. 80,000 tons year-1) and manure (app. 50,000 tons year-1) and other materials in lesser amounts. Methane potentials of the two “new” biomass fractions were measured to predict their contribution to the biogas production. Measured methane potentials were: Pectin waste: 370 to 460 ml CH4 g VS-1...... and cast seaweed (winter sample): 118 ml CH4 g VS-1. The predicted annual biogas production of the plant was 5.4 million m3 CH4. An environmental assessment concluded that a biogas plant using the aforementioned organic materials will reduce greenhouse gas emissions between 25,000 tons CO2 year-1 and 40...

  13. 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).

  14. Thermal-Responsive Behavior of a Cell Compatible Chitosan/Pectin Hydrogel.

    Science.gov (United States)

    Birch, Nathan P; Barney, Lauren E; Pandres, Elena; Peyton, Shelly R; Schiffman, Jessica D

    2015-06-01

    Biopolymer hydrogels are important materials for wound healing and cell culture applications. While current synthetic polymer hydrogels have excellent biocompatibility and are nontoxic, they typically function as a passive matrix that does not supply any additional bioactivity. Chitosan (CS) and pectin (Pec) are natural polymers with active properties that are desirable for wound healing. Unfortunately, the synthesis of CS/Pec materials have previously been limited by harsh acidic synthesis conditions, which further restricted their use in biomedical applications. In this study, a zero-acid hydrogel has been synthesized from a mixture of chitosan and pectin at biologically compatible conditions. For the first time, we demonstrated that salt could be used to suppress long-range electrostatic interactions to generate a thermoreversible biopolymer hydrogel that has temperature-sensitive gelation. Both the hydrogel and the solution phases are highly elastic, with a power law index of close to -1. When dried hydrogels were placed into phosphate buffered saline solution, they rapidly rehydrated and swelled to incorporate 2.7× their weight. As a proof of concept, we removed the salt from our CS/Pec hydrogels, thus, creating thick and easy to cast polyelectrolyte complex hydrogels, which proved to be compatible with human marrow-derived stem cells. We suggest that our development of an acid-free CS/Pec hydrogel system that has excellent exudate uptake, holds potential for wound healing bandages.

  15. Extraction and Characterization of Highly Gelling Low Methoxy Pectin from Cashew Apple Pomace

    Directory of Open Access Journals (Sweden)

    Beda M. Yapo

    2013-12-01

    Full Text Available Investigation on the pectic substances of cashew (Anacardium occidentale L. apple under different acid-extraction conditions (pH 1.0, 1.5, and 2.0 showed that more than 10%–25% of A. occidentale pectins (AOP could be extracted, depending on the extractant strength. The extracted AOP contained high amounts of galacturonic acid (GalA: 69.9%–84.5% with some neutral sugars of which rhamnose (Rha: 1.3%–2.5%, arabinose (Ara: 2.6%–5.4%, and galactose (Gal: 4.7%–8.6% were the main constituents. The degree of methoxylation (DM was in the range of 28%–46% and was only slightly affected by the extractant strength, thereby indicating isolation of naturally low methoxy pectins (LMP. In terms of gelling capability, AOP yielded firmer Ca2+-mediated LMP gels than commercial citrus LMP with comparable DM. Cashew apple pomace, therefore, appears to be a potentially viable source for possible production of “non-chemically or enzymatically-tailored” LMP.

  16. 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.

  17. Comparison of the moisturization efficacy of two vaginal moisturizers: Pectin versus polycarbophil technologies.

    Science.gov (United States)

    Caswell, Michael; Kane, Michael

    2002-01-01

    This study was designed to compare the vaginal deposition and moisturization of two vaginal moisturizers, Summer's Eve (SE), based on pectin, and Replens (Rp), based on polycarbophil, in a double-blind crossover study design. Fifty-one female patients were each randomly assigned to one of two treatment groups. After a one-week washout period, the products were used for two weeks. After another one-week washout period, product assignments were switched. Colposcopy examinations were performed at the beginning and at the end of each product use. Of the forty-seven patients completing the study, 41 (87%) were found to have no vaginal residue after SE vaginal moisturizer, while only 25 (53%) were found to have no vaginal residue after using Rp vaginal moisturizer. No difference in relief of vaginal dryness or in product acceptance was found between the two products. This study shows that the use of SE vaginal moisturizer, based on pectin, resulted in significantly less vaginal residue compared to Rp vaginal moisturizer, based on polycarbophil, and in comparable relief of vaginal dryness. These results strongly suggest that bioadhesion is not important in vaginal moisturizers.

  18. 柑橘皮果胶提取条件优化及其组分益生作用的研究%Optimization of extraction of pectin from the citrus peel and the prebiotic function of pectin fraction

    Institute of Scientific and Technical Information of China (English)

    杨蕾; 蔡为荣; 王伟霜; 孙涛涛

    2015-01-01

    采用盐酸水解、乙醇沉淀法从柑橘皮中提取果胶.在单因素实验结果基础上,选择浸提 pH、浸提温度、浸提时间、浸提固液比为自变量,果胶得率为响应值,采用 Box-Behnken 响应面分析方法研究各自变量交互作用及其对果胶得率的影响.模拟得到二次多项式回归方程的预测模型,并确定柑橘皮果胶的最佳提取条件为:浸提 pH 1.75,浸提温度83℃,浸提时间88 min,固液比1∶40,在此条件下,果胶得率达到22.01%.除杂后的果胶经超滤获得分子量不同的4个组分,双歧杆菌体外发酵结果显示,4个果胶组分均有双歧杆菌增殖作用.说明果胶具有潜在益生功能,且果胶组分分子量小,增殖效果更好.%The crude pectin were extracted from the citrus peel with hydrochloric acid and precipitated with ethanol.The pH,extraction temperature,extraction time,and liquid-solid ratio were selected as the argument based on the result of single factors.The Box-Benhnken of response surface method were used to study the interaction of each argument and their effect on the yield of pectin,and the second-order pol-ynomial equation was obtained.The optimum values of extraction pH,temperature,time and solid-liquid ratio were determined to be 1.75,83 ℃,88 min and 1∶40 respectively,under these conditions,the pectin yield was 22.01%.Pectin was purified and divided into four molecular weight fraction.The result showed that the four pectin fractions can promote the growth of the bifidobacterium,which showed that pectin-oligosaccharides have the potential prebiotic function and the prebiotic effect of the pectin fraction in-creased with the molecular weight decreased.

  19. Extração de pectina de goiaba desidratada Extraction of pectin from dehydrated guava

    Directory of Open Access Journals (Sweden)

    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

  20. Two-step sequential cross-linking of sugar beet pectin for transforming zein nanoparticle-based Pickering emulsions to emulgels.

    Science.gov (United States)

    Soltani, Sahar; Madadlou, Ashkan

    2016-01-20

    Nanosized (<100 nm) zein spheres were employed for fabrication of a series of fish O/W Pickering emulsions. Although surface tension measurement informed the high potency of zein particles for interfacial adsorption, the prepared emulsions destabilized shortly. Electrostatic deposition of sugar beet pectin onto zein particles interfacial layer at pH 4.0 increased significantly the emulsion stability which was attributed to enhanced steric and electrostatic repulsions based on ζ-potential measurements. Pectin enrichment also increased the viscosity of the continuous phase of emulsion. Injection of the oxidative enzyme laccase into the pectin-enriched emulsion to cross-link the feruloyl-bearing pectin molecules and the subsequent addition of CaCl2 to set ion-mediated cross-linkages between carboxyl groups of pectin chains transformed Pickering emulsions to emulgels. The higher the pectin content, the shorter was the gelation time of emulsions. The obtained emulgels were self-standing and became harder along with increasing pectin content.

  1. Novel pectin-based nanoparticles prepared from nanoemulsion templates for improving in vitro dissolution and in vivo absorption of poorly water-soluble drug.

    Science.gov (United States)

    Burapapadh, Kanokporn; Takeuchi, Hirofumi; Sriamornsak, Pornsak

    2012-10-01

    The purpose of this study was to improve in vitro dissolution and in vivo absorption of itraconazole (ITZ), a poorly water-soluble drug, by means of novel pectin-based nanoparticles prepared from nanoemulsion templates. Nanoemulsion templates were prepared by a high-pressure homogenization using pectin (i.e., 0.5-3.0%w/w low-methoxyl pectin (LMP), amidated low-methoxyl pectin (ALMP), or high-methoxyl pectin (HMP)) as an emulsifier and chloroform as an oil phase. HMP provided good oil-in-water emulsions with ITZ loaded in the oil phase. The chloroform in nanoemulsions was then removed to produce the suspensions of nanoparticles dispersed in water phase. After lyophilization, the dried core-shell nanoparticles with good properties in terms of redispersibility, dissolution, and stability were obtained. The alteration of ITZ crystallinity was clearly observed from powder X-ray diffractogram while no interaction between ITZ and pectin was found in the nanoparticles. The ITZ-loaded nanoparticles showed high percent drug dissolved, especially those prepared from HMP, and could maintain their good dissolution properties even after 6-month storage. The in vivo absorption study in fasted rats demonstrated that pectin-based nanoparticles prepared from nanoemulsion templates could improve absorption of ITZ, that is, 1.3-fold higher than the ITZ commercial product (pin vivo plasma profile. These findings suggested that HMP-based nanoparticles seem to be a promising formulation due to their high AUC(0-24h) and C(max).

  2. 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

  3. Ultrasound-assisted heating extraction of pectin from grapefruit peel: optimization and comparison with the conventional method.

    Science.gov (United States)

    Wang, Wenjun; Ma, Xiaobin; Xu, Yuting; Cao, Yongqiang; Jiang, Zhumao; Ding, Tian; Ye, Xingqian; Liu, Donghong

    2015-07-01

    The extraction of pectin from grapefruit peel by ultrasound-assisted heating extraction (UAHE) was investigated using response surface methodology and compared with the conventional heating extraction (CHE). The optimized conditions were power intensity of 12.56 W/cm(2), extraction temperature of 66.71°C, and sonication time of 27.95 min. The experimental optimized yield was 27.34%, which was well matched with the predicted value (27.46%). Compared with CHE, UAHE provided higher yield increased by 16.34% at the temperature lowered by 13.3°C and the time shortened by 37.78%. Image studies showed that pectin extracted by UAHE showed better color and more loosen microstructure compared to that extracted by CHE, although Fourier Transform Infrared Analysis indicated insignificant difference in their chemical structures. Furthermore, UAHE pectin possessed lower viscosity, molecular weight and degree of esterification, but higher degree of branching and purity than CHE pectin, indicating that the former was preliminarily modified during the extraction process.

  4. 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

    fibre separation. Hemicellulose removal by NaOH further improved fibre surface cleanliness. Removal of epidermal and parenchyma cells combined with improved fibre separation decreased composite porosity factor. As a result, pectin removal increased composite stiffness and ultimate tensile strength (UTS...

  5. 1H NMR and Rheological Studies of the Calcium Induced Gelation Process in Aqueous Low Methoxyl Pectin Solutions

    Science.gov (United States)

    Dobies, M.; Kuśmia, S.; Jurga, S.

    2006-07-01

    The 1H NMR relaxometry in combination with water proton spin-spin relaxation time measurements and rheometry have been applied to study the ionic gelation of 1% w/w aqueous low methoxyl pectin solution induced by divalent Ca2+ cations from a calcium chloride solution. The model-free approach to the analysis of 1H NMR relaxometry data has been used to separate the information on the static (β) and dynamic () behaviour of the systems tested. The 1H NMR results confirm that the average mobility of both water and the pectin molecules is largely dependent on the concentration of the cross-linking agent. The character of this dependency (β, and T2 vs. CaCl2 concentration) is consistent with the two-stage gelation process of low methoxyl pectin, in which the formation of strongly linked dimer associations (in the range of 0-2.5 mM CaCl2) is followed by the appearance of weak inter-dimer aggregations (for CaCl2≥ 3.5 mM). The presence of the weak gel structure for the sample with 3.5 mM CaCl2 has been confirmed by rheological measurements. Apart from that, the T1 and T2 relaxation times have been found to be highly sensitive to the syneresis phenomenon, which can be useful to monitor the low methoxyl pectin gel network stability.

  6. Hydrolytic and oxidate stability of L-(+) -ascorbic acid supported in pectin films: Influence of the macromolecular structure and calcium presence

    Science.gov (United States)

    The hydrolytic and oxidative stability of L-(+)-ascorbic acid (AA) into plasticized pectin films were separately studied in view of preserving vitamin C activity and/or to achieve localized antioxidant activity at pharmaceutical and food interfaces. Films were made with each one of the enzymatically...

  7. 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 aberrati

  8. Facile synthesis of pectin-stabilized magnetic graphene oxide Prussian blue nanocomposites for selective cesium removal from aqueous solution.

    Science.gov (United States)

    Kadam, Avinash A; Jang, Jiseon; Lee, Dae Sung

    2016-09-01

    This work focused on the development of pectin-stabilized magnetic graphene oxide Prussian blue (PSMGPB) nanocomposites for removal of cesium from wastewater. The PSMGPB nanocomposite showed an improved adsorption capacity of 1.609mmol/g for cesium, compared with magnetic graphene oxide Prussian blue, magnetic pectin Prussian blue, and magnetic Prussian blue nanocomposites, which exhibited adsorption capacities of 1.230, 0.901, and 0.330mmol/g, respectively. Increased adsorption capacity of PSMGPB nanocomposites was attributed to the pectin-stabilized separation of graphene oxide sheets and enhanced distribution of magnetites on the graphene oxide surface. Scanning electron microscopy images showed the effective separation of graphene oxide sheets due to the incorporation of pectin. The optimum temperature and pH for adsorption were 30°C and 7.0, respectively. A thermodynamic study indicated the spontaneous and the exothermic nature of cesium adsorption. Based on non-linear regression, the Langmuir isotherm fitted the experimental data better than the Freundlich and Tempkin models.

  9. Pectin extraction from quince (Cydonia oblonga) pomace applying alternative methods: effect of process variables and preliminary optimization.

    Science.gov (United States)

    Brown, Valeria Anahí; Lozano, Jorge E; Genovese, Diego Bautista

    2014-03-01

    The objectives of this study were to introduce alternative methods in the process of pectin extraction from quince pomace, to determine the effect of selected process variables (factors) on the obtained pectin, and to perform a preliminary optimization of the process. A fractional factorial experimental design was applied, where the factors considered were six: quince pomace pretreatment (washing vs blanching), drying method (hot air vs LPSSD), acid extraction conditions (pH, temperature, and time), and pectin extract concentration method (vacuum evaporation vs ultrafiltration). The effects of these factors and their interactions on pectin yield (Y: 0.2-34.2 mg/g), GalA content (44.5-76.2%), and DM (47.5-90.9%), were determined. For these three responses, extraction pH was the main effect, but it was involved in two and three factors interactions. Regarding alternative methods, LPSSD was required for maximum Y and GalA, and ultrafiltration for maximum GalA and DM. Response models were used to predict optimum process conditions (quince blanching, pomace drying by LPSSD, acid extraction at pH 2.20, 80 , 3 h, and concentration under vacuum) to simultaneously maximize Y (25.2 mg/g), GalA (66.3%), and DM (66.4%).

  10. 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 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...

  11. 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.

  12. Facile synthesis of pectin coated Fe{sub 3}O{sub 4} nanospheres by the sonochemical method

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Junjun; Wu, Shixi [National Special Superfine Powder Engineering Research Center, Nanjing University of Science and Technology, Nanjing 210094 (China); Jiang, Wei, E-mail: climentjw@126.com [National Special Superfine Powder Engineering Research Center, Nanjing University of Science and Technology, Nanjing 210094 (China); Li, Pingyun; Chen, Xiaolong; Liu, Li; Liu, Jie; Sun, Danping; Chen, Wei; Chen, Binhua; Li, Fengsheng [National Special Superfine Powder Engineering Research Center, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2013-04-15

    Pectin coated Fe{sub 3}O{sub 4} magnetic nanospheres (PCMNs) were synthesized by the sonochemical method. The Fe{sub 3}O{sub 4} nanoparticles were prepared by chemical precipitation as reported in the previous articles, and the PCMNs were characterized by transmission electron microscopy, dynamic light scattering, thermogravimetric analysis, Fourier-transform infrared spectroscopy, a vibrating sample magnetometer and energy dispersive X-ray spectrum. The results indicated that the magnetic nanoparticles have been coated by pectin, magnetite content of which was up to 63%, with the saturation magnetization being 32.69 emu/g. The formation mechanism and further application of PCMNs have also been discussed. The results show that the PCMNs can be applied to biomedical applications. -- Highlights: ► Using the sonochemical method to synthesize the pectin coated magnetic nanospheres makes it easier to load the drugs. ► Pectin is difficult to digest and can only be degraded in colon; it has a bright future in colon targeting. ► This method can control the particle size distribution and magnetic content effectively.

  13. The combination of atomic force microscopy and sugar analysis to evaluate alkali-soluble Canna edulis Ker pectin.

    Science.gov (United States)

    Zhang, Juan; Cui, Junhui; Xiao, Lin; Wang, Zhengwu

    2014-08-01

    Alkali-soluble pectin, which has been extracted from Canna edulis Ker, was characterized by single sugar determination and atomic force microscopy (AFM). The results indicated that the amounts of four predominant sugars including arabinose (Ara), glucose (Glc), galactose (Gal) and galacturonic acid (GalA) significantly decreased during the process of mild acid hydrolysis. The decreasing rates of these four sugars followed a sequential order of Ara>Gal>Glc>GalA. The homogalacturonan (HG) chain present in pectin, and the quantity of branched material is greater than the sample containing the main neutral sugars. The results indicated that the neutral sugar and HG side chains are attached to pectin as part of the rhamnogalacturonan I (RGI) complex. Moreover, hydrolysis leads to the reduction of mean lengths of backbone and branch, as well as the number/weight-average molecular weight. Meanwhile, the amount of short chain fractions increased during hydrolysis. Furthermore, the decrease of the polymerization degree of alkali-soluble C. edulis pectin as a function of the hydrolysis time could be described by a first-order exponential decay function.

  14. Extraction and Determination of Pectin from Sisal Residue%剑麻渣果胶提取与测定

    Institute of Scientific and Technical Information of China (English)

    陶进转; 陈伟南

    2014-01-01

    从剑麻的麻渣、纤维中提取果胶,测定果胶的含量、纯度和酯化度。将湿麻渣在密封与敞开空气中自然发酵后提取果胶,探讨湿麻渣在发酵后对果胶品质的影响。结果表明,果胶得率最高的是湿麻渣(13.342%),最低的是直纤维(0.450%),干麻渣的果胶得率(1.662%)略高于湿纤维(1.326%)与乱纤维(1.264%)的;果胶纯度最高的是直纤维(73.360%),最低的是干麻渣(32.567%)。直纤维果胶的酯化度(45.452%)略大于麻渣和乱纤维的(32%~35%);湿麻渣经过自然发酵后,果胶得率与纯度均降低,但湿麻渣完全发酵后的果胶酯化度(33.432%)接近于干麻渣的(33.156%)。%To extract pectin from sisal residue and fiber , the content , purity and esterification de-gree of pectin were determined.Pectin was extracted from fresh sisal residue after fermentation in the air-proof and ample air , and the effects on the quality of pectin were investigated.The results showed that fresh sisal residue yields the most pectin ( 13.342%) , and the fiber yields the least ( 0.450%) .The yield of pectin extracted from dry sisal residue (1.662%) was higher than these extracted from wet kinky fiber (1.326%) and dry kinky fiber ( 1.264%) slightly.The highest purity of pectin was from fiber (73.360%) , and the lowest was from dry sisal residue (32.567%) .The esterification degree of pec-tin extracted from fiber (45.452%) was higher than these of dry sisal residue and the kinky fiber (32%~35%) .The yield and purity of pectin decreased while the fresh sisal residue was fermented in nature condition.But the result of esterification degree of pectin extracted from sisal residue ( 33.432%) fer-mented completely was close to the one of dry sisal residue (33.156%) .

  15. Pectin Biosynthesis: GALS1 in Arabidopsis thaliana Is a β-1,4-Galactan β-1,4-Galactosyltransferase [C][W][OA

    DEFF Research Database (Denmark)

    Liwanag, April Jennifer Madrid; Ebert, Berit; Verhertbruggen, Yves

    2012-01-01

    β-1,4-Galactans are abundant polysaccharides in plant cell walls, which are generally found as side chains of rhamnogalacturonan I. Rhamnogalacturonan I is a major component of pectin with a backbone of alternating rhamnose and galacturonic acid residues and side chains that include α-1,5-arabinans......, β-1,4-galactans, and arabinogalactans. Many enzymes are required to synthesize pectin, but few have been identified. Pectin is most abundant in primary walls of expanding cells, but β-1,4-galactan is relatively abundant in secondary walls, especially in tension wood that forms in response...

  16. Formulation development and evaluation of novel oral jellies of carbamazepine using pectin, guar gum, and gellan gum

    Directory of Open Access Journals (Sweden)

    Katakam Prakash

    2014-01-01

    Full Text Available Medicated jelly formulations are more suitable for pediatric, geriatric and dysphagic patients, which offer rapid dissolution and absorption of drugs thereby early onset of action. The aim was to develop and evaluate oral jelly formulations of carbamazepine (CBZ. Carbamazepine oral jellies were prepared to employ pectin, guar gum and gellan gum alone and pectin-guar gum combination. Preformulation studies, organoleptic, physical characteristics, drug content, pH, spreadability, rheological properties, syneresis, taste masking, in vitro dissolution testing, drug release kinetics and stability studies were conducted. The Fourier transform infrared and differential scanning calorimeter studies showed that there was no interaction between drug and excipients. The pH of all the formulations was found between pH 6.37 ± 0.03 and 6.83 ± 0.04. The concentration of gelling agents influenced the spreadability. Syneresis was observed in jellies made from guar gum alone, whereas those made from pectin and guar gum it was absent. The optimized formulations (F3, F11 and F15 masked the bitter taste of CBZ and demonstrated acceptable flavor and mouth feel. All formulations showed more than 50% drug release in 15 min except those made of gellan gum alone. The formulations F3, F11 and F15, were found stable for 90 days as per International Conference on Harmonization stability protocol. Carbamazepine jellies made from pectin (F3, 1.2%, gellan gum (F11, 1.5% and pectin-guar gum (F15, 1:0.4% were found more successful and could be employed to improve the palatability and acceptability by pediatric, geriatric and dysphagic patients. The jellies could be useful to overcome the problems of poorly soluble CBZ.

  17. 芦柑皮中果胶提取研究%Study on Extraction of Pectin from Citrus Peel

    Institute of Scientific and Technical Information of China (English)

    吴环

    2012-01-01

    [Objective] The aim was to obtain the optimum method for extracting pectin from citrus peel. [ Method] With dried citrus peel powder as raw material, by using the method of acid hydrolysis deposition and L9 (34 ) orthogonal test, the extraction conditions were optimized. [Result] The optimum conditions were pH 2.0, temperature 80 ℃, time 70 min, solid-liquid ratio 1:30 g/ml. Under the above conditions, the average yield of pectin was 16. 6% , pectin purity was 87. 6% , the content of methoxyl pectin was 76. 8% . [ Conclusion] The study will provide reference for comprehensive utilization of citrus peel and pectin autonomous production in China.%[目的]研究从芦柑皮中提取果胶的最佳方法.[方法]以烘干的芦柑皮粉末为原料,采用酸水解乙醇沉淀法提取果胶,并应用L9(34)正交试验对提取条件进行了优化.[结果]确定最佳提取条件为pH 2.0、提取温度80℃、提取时间70 min、料液比1:30g/ml,在此条件下果胶平均得率为16.60%,果胶纯度为87.6%,甲氧基果胶含量为76.8%.[结论]为芦柑皮的综合利用和我国果胶自主生产提供了参考.

  18. 香蕉枯萎病菌果胶甲基酯酶基因的克隆与生物信息学分析%Cloning and Bioinformatic Analysis of Pectin Methylesterase Gene from Fusarium oxyporum f.sp.cubense

    Institute of Scientific and Technical Information of China (English)

    董章勇; 王振中

    2012-01-01

    旨在了解香蕉枯萎病菌(Fusarium oxysporum f.sp.cubense)4号生理小种(FOC4) PME基因序列特征,根据同源物种PME相关序列设计引物,利用PCR和RT-PCR技术,克隆FOC4序列基因和开放阅读框,命名为Foc4Pme.结果表明,所获得的PME基因均含有2个内舍子和3个外显子,990 bp的片段,编码329个氨基酸.预测编码蛋白有信号肽,具有1个功能位点,其分子质量和等电点分为34.894 8 kD和9.17,该蛋白为稳定存在的蛋白.该蛋白疏水性最大值为2.022,最小值为-2.156,大部分区域为亲水区.该基因编码的蛋白具有一定保守性,进化上与镰刀菌亲缘关系最近.

  19. Extraction and characterization of the pectin methylesterase (PME of waste agroindustrial of the pineapple pearlExtração e caracterização de pectinametilesterase (PME de resíduos agroindustrais de abacaxi pérola

    Directory of Open Access Journals (Sweden)

    Marcelo Franco

    2012-12-01

    Full Text Available The objective was to obtain and characterize pectinmethylesterase (PME of industrial residue from the Pearl Pineapple. Specific activities, the optimum conditions of pH and temperature, and also the thermal stability partially purified and concentrated PME were determined. The PME specific activity was 6.36 U/mg. The pH optimum of 7.5 PME was extracted, also considering alkaline. During the trial time, the partially purified PME maintained itself stable upon exposure to the temperatures of 25 and 60ºC. It obtained an activity elevation between 40 and 50ºC. In temperatures above 70ºC, there was a substantial reduction in a specific activity. The partially purified PME showed three gel polyacrylamide SDS-PAGE bands of apparent molar mass (MM of 25.4 and 23.1 kDa and 16.4 kDa. These results demonstrate the feasibility of PME extraction from the Pearl Pineapple’s processed residue and its potential for use in manufacturing pulp and fruit juices, since the currently applied enzymes are imported and expensive. Objetivou obter e caracterizar pectinametilesterase (PME de resíduos industriais de abacaxi Pérola. Foram determinadas a atividade específica, as condições ótimas de pH e temperatura, bem como a estabilidade térmica da PME concentrada (PME-C e PME parcialmente purificada (PME-PP. A atividade específica da PME foi de 6,36 U/MG. O pH ótimo da PME extraída foi 8,5, classificada como alcalina. Durante o tempo de ensaio, a PME-PP manteve-se estável mediante exposição a temperaturas entre 25 e 60°C, obtendo uma elevação da atividade em 40 e 50°C. Em temperaturas superiores a 70°C, houve uma redução na atividade específica. A PME-PP mostrou três bandas no gel poliacrilamida SDS-PAGE de massas molares aparentes (MM de 25,4 e 23,1 kDa e 16,4 kDa. Os resultados obtidos demonstram ser possível explorar o potencial de uso da PME extraída a partir do subproduto do processamento de abacaxi Pérola. Esta enzima está presente em praticamente todas as preparações enzimáticas comerciais para proteção e melhoramento da textura e firmeza de frutas e vegetais processados, na extração e clarificação de sucos de frutas. Atualmente, são importadas e tem elevado custo.

  20. Aluminum-induced changes in cell-wall pectin methylesterase activity of wheat seedlings in relation to their aluminum tolerance%铝胁迫下小麦根细胞壁果胶甲酯酶活性的变化及其与耐铝性的关系

    Institute of Scientific and Technical Information of China (English)

    唐剑锋; 罗湖旭; 林咸永; 章永松; 李刚

    2006-01-01

    研究了2个小麦基因型西矮麦1号(耐性)和辐84系(敏感)在铝胁迫下根尖细胞壁果胶甲酯酶(PME)活性的变化及其与根系对铝毒反应的关系.结果表明,30 μmol·L-1 AlCl3处理6 h和24 h后,小麦根系伸长受到了明显的抑制,但辐84系受抑制更为明显.小麦根系0~10 mm根段的铝含量显著高于10~20 mm根段,且辐84系在0~10 mm根段铝含量高于西矮麦1号.铝胁迫下小麦根尖0~10 mm根段细胞壁果胶糖醛酸含量提高,但辐84系不仅果胶糖醛酸含量较高而且提高幅度更为明显.铝处理下,西矮麦1号根尖果胶甲酯酶(PME)活性无明显变化,但辐84系0~10 mm根段PME活性在铝处理6 h后提高,处理24 h则略有下降.敏感基因型根尖细胞壁PME活性高于耐性基因型,在短期胁迫(6 h)下敏感基因型0~10 mm根段细胞壁PME活性明显提高,在24 h时则略有降低;而耐铝基因型没有明显的变化.上述结果显示,辐84系在无铝胁迫下根尖细胞壁果胶甲基酯酶活性较高,而且在短期铝胁迫下果胶含量和果胶甲基酯酶活性提高幅度较大,增加了细胞壁铝的结合位点,导致较多的铝在根尖积累是其根系伸长受铝抑制程度较高的可能原因.

  1. A continuous membrane microbioreactor system for development of integrated pectin modification and separation processes

    DEFF Research Database (Denmark)

    Zainal Alam, Muhd Nazrul Hisham Bin; Pinelo, Manuel; Samanta, Kama

    2011-01-01

    Evaluation of novel enzyme reactions and reactor systems is often hampered by costs related to obtaining sufficient amounts of enzymes. In this respect, it will be advantageous to assess new enzymatic processes in microbioreactors designed to resemble genuine reactor systems. In this work, we...... present a continuous membrane microbioreactor prototype for development of enzyme catalyzed degradation of pectin. Membrane reactors are becoming increasingly important for the novel ‘biorefining’ type of processes that either require product removal to avoid product inhibition or rest on partial...... hydrolysis of the substrate to obtain e.g. value-added oligosaccharides from complex biopolymers. The microbioreactor prototype was fabricated from poly(methylmethacrylate) (PMMA) and poly(dimethylsiloxane) (PDMS) and designed as a loop reactor (working volume approximately 190μL) integrated...

  2. Influence of phytic acid and its metal complexes on the activity of pectin degrading polygalacturonase.

    Science.gov (United States)

    Asghar, Uzma; Rehman, Haneef Ur; Qader, Shah Ali Ul; Maqsood, Zahida Tasneem

    2013-06-05

    Polygalacturonase is one of the important requirements of different microorganism to cause pathogenicity and spoilage of fruits and vegetables that involved in degradation of pectin during plant tissue infections. In current study, 20 mM phytic acid inhibited 70% activity of polygalacturonase. The effect of different concentration of metal ions such as Cu(+2), Al(+3) and V(+4) were studied separately and it was found that the 20 mM of these metal ions inhibited 37.2%, 79%, and 53% activity of polygalacturonase, respectively. Finally, the complexes of phytic acid and these metals ions were prepared and 1:1 ratio of phytic acid and metal ions complexes showed maximum inhibitory activity of enzyme as compared to complexes having 1:2 and 1:3 ratio except phytate-copper complexes which showed no inhibitory effect on the activity of polygalacturonase.

  3. Tamarindus indica pectin blend film composition for coating tablets with enhanced adhesive force strength.

    Science.gov (United States)

    Khurana, Rajneet; Singh, Kuldeep; Sapra, Bharti; Tiwary, A K; Rana, Vikas

    2014-02-15

    Tablet coating is the most useful method to improve tablet texture, odour and mask taste. Thus, the present investigation was aimed at developing an industrially acceptable aqueous tablet coating material. The physico-chemical, electrical and SEM investigations ensures that blending of Tamarindus indica (Linn.) pectin (TP) with chitosan gives water resistant film texture. Therefore, CH-TP (60:40) spray coated tablets were prepared. The evaluation of CH-TP coated tablets showed enhanced adhesive force strength (between tablet surface to coat) and negligible cohesive force strength (between two tablets) both evaluated using texture analyzer. The comparison of CH-TP coated tablets with Eudragit coated tablets further supported superiority of the former material. Thus, the findings pointed towards the potential of CH-TP for use as a tablet coating material in food as well as pharmaceutical industry.

  4. Enzymatic accessibility of fiber hemp is enhanced by enzymatic or chemical removal of pectin.

    Science.gov (United States)

    Pakarinen, A; Zhang, J; Brock, T; Maijala, P; Viikari, L

    2012-03-01

    Pectinolytic enzymes, steam explosion and alkaline treatment were used to assess the role of pectin for the accessibility of hydrolytic enzymes in the enzymatic hydrolysis of biomass. Hemp (Cannabis sativa L.), a potential energy crop especially in boreal climate with a low need of fertilizers, was used in the study either as untreated or anaerobically preserved raw material. Addition of pectinases increased the hydrolysis yield by 26%, 54%, and 64% from the theoretical carbohydrates of untreated, acid, and alkali-preserved materials, respectively. Steam explosion and hot alkali treatment increased the conversion of the total carbohydrates by 78% and 60%, respectively, compared to the untreated hemp. Elevated separation of cells within the hemp stalk tissues and an increased surface area was revealed after hot alkali or pectinase treatments, contributing to the increased conversion to sugars by commercial enzymes.

  5. 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.

  6. 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).

  7. 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

  8. 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.

  9. 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.

  10. Studies on PVA pectin cryogels containing crosslinked enzyme aggregates of keratinase.

    Science.gov (United States)

    Martínez, Yanina N; Cavello, Ivana; Cavalitto, Sebastián; Illanes, Andres; Castro, Guillermo R

    2014-05-01

    Polyvinyl alcohol-pectin (PVA-P) films containing enrofloxacin and keratinase were developed to treat wounds and scars produced by burns and skin injuries. However, in order to prevent enzyme inactivation at the interface between the patch and the scars, crosslinked enzyme aggregates (CLEAs) from a crude extract of keratinase produced by Paecilomyces lilacinus (LPSC#876) were synthesized by precipitation with acetone and crosslinking with glutaraldehyde. Soluble vs. CLEA keratinase (K-CLEA) activities were tested in 59% (v/v) hydrophobic (isobutanol and n-hexane) and hydrophilic (acetone and dimethylsulfoxide) solvents mixtures. K-CLEA activity was 1.4, 1.7 and 6.6 times higher in acetone, n-hexane and isobutanol than the soluble enzyme at 37 °C after 1 h of incubation, respectively. K-CLEA showed at least 45% of enzyme residual activity in the 40-65 °C range, meanwhile the soluble biocatalyst was fully inactivated at 65 °C after 1h incubation. Also, the soluble enzyme was completely inactivated after 12 h at pH 7.4 and 45 °C, even though K-CLEA retained full activity. The soluble keratinase was completely inactivated at 37 °C after storage in buffer solution (pH 7.4) for 2 months, meanwhile K-CLEAs kept 51% of their activity. K-CLEA loaded into polyvinyl alcohol (PVA) and PVA-P cryogels showed six times lower release rate compared to the soluble keratinase at skin pH (5.5). Small angle X-ray scattering (SAXS) analysis showed that K-CLEA bound to pectin rather than to PVA in the PVA-P matrix.

  11. Plant-derived pectin nanocoatings to prevent inflammatory cellular response of osteoblasts following Porphyromonas gingivalis infection

    Science.gov (United States)

    Meresta, Anna; Folkert, Justyna; Gaber, Timo; Miksch, Korneliusz; Buttgereit, Frank; Detert, Jacqueline; Pischon, Nicole; Gurzawska, Katarzyna

    2017-01-01

    Background Bioengineered plant-derived Rhamnogalacturonan-Is (RG-Is) from pectins are potential candidates for surface nanocoating of medical devices. It has recently been reported that RG-I nanocoatings may prevent bacterial infection and improve the biocompatibility of implants. The aim of the study was to evaluate in vitro impact of bioengineered RG-I nanocoatings on osteogenic capacity and proinflammatory cytokine response of murine osteoblasts following Porphyromonas gingivalis infection. Methods Murine MC3T3-E1 osteoblasts and isolated primary calvarial osteoblasts from C57BL/6J (B6J osteoblasts) mice were infected with P. gingivalis and incubated on tissue culture polystyrene plates with or without nanocoatings of unmodified RG-Is isolated from potato pulps (PU) or dearabinanated RG-Is (PA). To investigate a behavior of infected osteoblasts cultured on RG-Is cell morphology, proliferation, metabolic activity, mineralization and osteogenic and pro-inflammatory gene expression were examined. Results Following P. gingivalis infection, PA, but not PU, significantly promoted MC3T3-E1 and BJ6 osteoblasts proliferation, metabolic activity, and calcium deposition. Moreover, Il-1b, Il-6, TNF-α, and Rankl gene expressions were downregulated in cells cultured on PU and to a higher extent on PA as compared to the corresponding control, whereas Runx, Alpl, Col1a1, and Bglap gene expressions were upregulated vice versa. Conclusion Our data clearly showed that pectin RG-Is nanocoating with high content of galactan (PA) reduces the osteoblastic response to P. gingivalis infection in vitro and may, therefore, reduce a risk of inflammation especially in immunocompromised patients with rheumatoid or periodontal disorders. PMID:28138240

  12. KARAKTERISASI KOMPOSIT FILM EDIBLE PEKTIN DAGING BUAH PALA (Myristica fragrans Houtt DAN TAPIOKA [Characterization of Edible Film Composite Made of Pectin from Nutmeg Mesocarp and Tapioca

    Directory of Open Access Journals (Sweden)

    Payung Layuk 1

    2002-08-01

    Full Text Available The objective of the research was to investigate the properties of pectin derived from mesocarp of nutmeg (Mysristica fragrans Houtt and edible film made from the pectin and added tapioca. Pectin was extracted from mesocarp of nutmeg using 0.5% of EDTA at pH 1.5-2, and temperature at 90°C for 1 hour. The first group of edible film was prepared using 1% (w/v of pectin, 1.6% CaCl2, 1% glycerol and various concentration of tapioca (0-2%, w/v. Second group of edible film was prepared using 1% of pectin, 1.6 % CaCl2, 1% glycerol and 2% tapioca and various concentration of palmitic acid (0-0,08 w/v. Physical, mechanical and barrier properties of the films were examined and its capability to reduce weight loss of small pieces of apples during storage was also measured.The result showed that yield of isolated pectin was 20.73% (w/w having methoxyl content 11.43%, and polygalacturonic acid of 79.47%. Proximate analysis showed that protein, ash and water content in the isolated pectin were 7.86, 3.03 and 7.60%, respectively. Characteristics of first group of film showed that the higher concentration of tapioca added resulted in the higher of tensile strength and thickness. Data of the second groups of films showed that addition of palmitic acid up to 0,08% has no effects on tensile strength, thickness, elongation and water vapour transmission rate (WVTR of films. Small piece of apples coated or wrapped with edible film (1% pectin – 1,6% CaCl2-2% tapioca-1% glycerol and 0.04% palmitic acid had lower weight loss and better colour than those of control during storage.

  13. 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

  14. Extraction of Pectin from Sisal Residue%剑麻渣果胶提取工艺的研究

    Institute of Scientific and Technical Information of China (English)

    陈芳艳; 王林川; 杨艳; 陈希; 刘伟强

    2012-01-01

    The method of pectin extraction from sisal residue was optimized by orthogonal experiments, and pectin separation and decoloration were also studied. The optimized extraction conditions were as follows ; 2. 2 mol ? L"' oxalic acid-ammonium oxalate buffer as extracting agent, the solid to liquid ratio 0. 1 g ? mL"', time 90 min, temperature 80 t. Pectin was precipitated by alcohol at pH 4. 0; the yield of sisal pectin was 14. 87%. The primrose yellow pectin was decolored by 1. 8% -2.4% H2O2. The results of physicochemical property were that the degree of esterification of sisal pectin was 23% , galactu-ronic acid 66% , pH and ash all complying with Chinese light industey standards.%以剑麻渣为原料提取果胶,采用正交试验优化提取条件,并对剑麻果胶的分离及脱色进行研究,得出制备剑麻果胶的最佳工艺条件为:以2.2 mol· L-1的草酸-草酸铵缓冲溶液为提取剂,料液比为0.1 g· mL-1,时间90min,温度80℃,在pH4.0条件下用乙醇沉淀果胶,果胶产率为14.87%;用ω为1.8%~2.4%的过氧化氢脱色,获得浅黄色果胶.理化性质研究表明,剑麻果胶为酯化度23%的低酯果胶,ω(半乳糖醛酸)为66%,pH、灰分等指标均符合国家轻工行业标准.

  15. Localization of pectins and Ca2+ ions in unpollinated and pollinated wet (Petunia hybrida Hort. and dry (Haemanthus albiflos L. stigma.

    Directory of Open Access Journals (Sweden)

    Elzbieta Bednarska

    2005-12-01

    Full Text Available The subcellular localization of Ca2+ ions as well as esterified and deesterified pectins in unpollinated and pollinated wet (Petunia hybrida and dry (Haemanthus albiflos stigma was analyzed. Stigmas with different surfaces were found to differ in Ca2+ and pectin localization. In a wet Petunia hybrida stigma, Ca2+ ions were present in the exudate occurring in the intercellular spaces of secretory tissue before pollination. The exudate of an unpollinated stigma was the site of the localization of large amounts of deesterified pectins. Stigma penetration by pollen tubes induced the lysis of this category of pectins. The epidermal cells walls of the dry Haemanthus albiflos stigma before pollination lacked free and loosely bound Ca2+ ions. Pollination induced an accumulation of these ions in the apoplast of the stigma epidermal cells. In cells walls of an unpollinated stigma, mainly esterified pectins were present. Their deesterification took place after pollination at the site of pollen grain adhesion and then at the site of pollen tube growth. These results have shown that wet and dry stigmas differ in pectin metabolism and in the mechanism of forming a calcium environment at the site of pollen grain germination.

  16. Studies on sorption, desorption, regeneration and reuse of sugar-beet pectin gels for heavy metal removal

    Energy Technology Data Exchange (ETDEWEB)

    Mata, Y.N. [Department of Materials Science and Metallurgical Engineering, Complutense University of Madrid, Ciudad Universitaria s/n 28040 Madrid (Spain); Blazquez, M.L., E-mail: mlblazquez@quim.ucm.es [Department of Materials Science and Metallurgical Engineering, Complutense University of Madrid, Ciudad Universitaria s/n 28040 Madrid (Spain); Ballester, A.; Gonzalez, F.; Munoz, J.A. [Department of Materials Science and Metallurgical Engineering, Complutense University of Madrid, Ciudad Universitaria s/n 28040 Madrid (Spain)

    2010-06-15

    This work reports the effectiveness of sugar-beet pectin xerogels for the removal of heavy metals (cadmium, lead and copper) after multiple batch sorption-desorption cycles, with and without a gels regeneration step. Metals were recovered from xerogel beads without destroying their sorption capability and the beads were successfully reused (nine cycles) without significant loss in both biosorption capacity and biosorbent mass. Metals uptake levelled off or increased after using a 1 M CaCl{sub 2} regeneration step after each desorption. Calcium, as a regenerating agent, increased the stability and reusability of the gels repairing the damage caused by the acid and removing the excess protons after each elution providing new binding sites. Because of their excellent reusability, pectin xerogels are suitable for metal remediation technologies.

  17. 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.

  18. Core-shell biopolymer nanoparticle delivery systems: synthesis and characterization of curcumin fortified zein-pectin nanoparticles.

    Science.gov (United States)

    Hu, Kun; Huang, Xiaoxia; Gao, Yongqing; Huang, Xulin; Xiao, Hang; McClements, David Julian

    2015-09-01

    Biopolymer core-shell nanoparticles were fabricated using a hydrophobic protein (zein) as the core and a hydrophilic polysaccharide (pectin) as the shell. Particles were prepared by coating cationic zein nanoparticles with anionic pectin molecules using electrostatic deposition (pH 4). The core-shell nanoparticles were fortified with curcumin (a hydrophobic bioactive molecule) at a high loading efficiency (>86%). The resulting nanoparticles were spherical, relatively small (diameter ≈ 250 nm), and had a narrow size distribution (polydispersity index ≈ 0.24). The encapsulated curcumin was in an amorphous (rather than crystalline form) as detected by differential scanning calorimetry (DSC). Fourier transform infrared (FTIR) and Raman spectra indicated that the encapsulated curcumin interacted with zein mainly through hydrophobic interactions. The nanoparticles were converted into a powdered form that had good water-dispersibility. These core-shell biopolymer nanoparticles could be useful for incorporating curcumin into functional foods and beverages, as well as dietary supplements and pharmaceutical products.

  19. Study on Extraction Technology of Pectin From Apple%苹果果胶提取工艺研究

    Institute of Scientific and Technical Information of China (English)

    杨本华; 要晓丽

    2015-01-01

    The extraction technology of pectin from apple was studied by using acid extraction .The experimental results showed that: the optimum conditions of extraction of pectin from apple is using citric acid as extraction solution , the pH of 1, extraction temperature of 65 ℃, the extracting time for 2 h, and solid -liquid ratio of 1:8.%采用酸法来提取苹果中的果胶粗多糖,并研究其提取工艺。实验结果表明,最佳提取条件为:提取液用柠檬酸,pH 值为1,提取温度为65℃,提取时间为2h,料液比为1:8。

  20. Isolation of pectin-enriched products from red beet (Beta vulgaris L. var. conditiva) wastes: composition and functional properties.

    Science.gov (United States)

    Fissore, E N; Ponce, N M A; Matkovic, L; Stortz, C A; Rojas, A M; Gerschenson, L N

    2011-12-01

    The present work was dedicated to the development of an extraction process for red beet (Beta vulgaris L. var. conditiva) by-products that preserves the high molecular weight of the macromolecules with the primary aim of waste upgrading. Our study concerns the extraction of pectin-enriched products with potential thickening properties for their usage in food formulation, as well as with some healthy physiological effect, by using citrate buffer (pH = 5.2) either alone or with enzymes (hemicellulase or cellulase) active on cell wall polysaccharide networks. Considering that red beet tissue contains ferulic acid, which cross-links pectin macromolecules through arabinose residues to anchor them into the cell wall, an alkaline pretreatment was also evaluated in order to perform polysaccharide hydrolysis in the cell wall network to accomplish higher renderings. Chemical composition and yield, as well as the in vitro glucose retention exerted by the isolated fiber products were finally analyzed.

  1. Improving the controlled delivery formulations of caffeine in alginate hydrogel beads combined with pectin, carrageenan, chitosan and psyllium.

    Science.gov (United States)

    Belščak-Cvitanović, Ana; Komes, Draženka; Karlović, Sven; Djaković, Senka; Spoljarić, Igor; Mršić, Gordan; Ježek, Damir

    2015-01-15

    Alginate-based blends consisting of carrageenan, pectin, chitosan or psyllium husk powder were prepared for assessment of the best formulation aimed at encapsulation of caffeine. Alginate-pectin blend exhibited the lowest viscosity and provided the smallest beads. Alginate-psyllium husk blend was characterised with higher viscosity, yielding the largest bead size and the highest caffeine encapsulation efficiency (83.6%). The release kinetics of caffeine indicated that the porosity of alginate hydrogel was not reduced sufficiently to retard the diffusion of caffeine from the beads. Chitosan coated alginate beads provided the most retarded release of caffeine in water. Morphological characteristics of beads encapsulating caffeine were adversely affected by freeze drying. Bitterness intensity of caffeine-containing beads in water was the lowest for alginate-psyllium beads and chitosan coated alginate beads. Higher sodium alginate concentration (3%) for production of hydrogel beads in combination with psyllium or chitosan coating would present the most favourable carrier systems for immobilization of caffeine.

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

    Science.gov (United States)

    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...

  3. KdgF, the missing link in the microbial metabolism of uronate sugars from pectin and alginate

    Science.gov (United States)

    Hobbs, Joanne K.; Lee, Seunghyae M.; Robb, Melissa; Hof, Fraser; Barr, Christopher; Abe, Kento T.; Hehemann, Jan-Hendrik; McLean, Richard; Abbott, D. Wade; Boraston, Alisdair B.

    2016-01-01

    Uronates are charged sugars that form the basis of two abundant sources of biomass—pectin and alginate—found in the cell walls of terrestrial plants and marine algae, respectively. These polysaccharides represent an important source of carbon to those organisms with the machinery to degrade them. The microbial pathways of pectin and alginate metabolism are well studied and essentially parallel; in both cases, unsaturated monouronates are produced and processed into the key metabolite 2-keto-3-deoxygluconate (KDG). The enzymes required to catalyze each step have been identified within pectinolytic and alginolytic microbes; yet the function of a small ORF, kdgF, which cooccurs with the genes for these enzymes, is unknown. Here we show that KdgF catalyzes the conversion of pectin- and alginate-derived 4,5-unsaturated monouronates to linear ketonized forms, a step in uronate metabolism that was previously thought to occur spontaneously. Using enzyme assays, NMR, mutagenesis, and deletion of kdgF, we show that KdgF proteins from both pectinolytic and alginolytic bacteria catalyze the ketonization of unsaturated monouronates and contribute to efficient production of KDG. We also report the X-ray crystal structures of two KdgF proteins and propose a mechanism for catalysis. The discovery of the function of KdgF fills a 50-y-old gap in the knowledge of uronate metabolism. Our findings have implications not only for the understanding of an important metabolic pathway, but also the role of pectinolysis in plant-pathogen virulence and the growing interest in the use of pectin and alginate as feedstocks for biofuel production. PMID:27185956

  4. Pectina: da matéria-prima ao produto final Pectin: from raw material to the final product

    Directory of Open Access Journals (Sweden)

    Maria H. G. Canteri

    2012-01-01

    Full Text Available A pectina, provavelmente a mais complexa macromolécula natural, é um heteropolissacarídeo contendo predominantemente resíduos de ácido galacturônico. Este polímero, do grupo das fibras dietéticas, é amplamente utilizado como geleificante e estabilizante na indústria de alimentos. O principal processo industrial para obtenção de pectina está baseado na solubilização da protopectina do bagaço de maçã e casca de frutos cítricos, realizada em condições levemente ácidas sob aquecimento. Estudos recentes têm reportado a extração de pectina de novas matérias-primas sob diferentes condições, com influência sobre a qualidade e sobre o rendimento do produto final, para aumentar sua qualidade reológica. Esta revisão descreve a estrutura, as fontes, as aplicações, o processo de extração industrial assim como as principais técnicas de caracterização da pectina.Pectin, probably the most complex macromolecule in nature is a hetero-polysaccharide containing predominantly residues of galacturonic acid (GalA. This polymer, which belongs to a group of dietary fibers, is widely used as a gelling agent and stabilizer in the food industry. The main industrial processing to obtain pectin is based on the solubilization of protopectin from apple pomace and citrus peels, which is done under low acidity and heated conditions. Recent studies have reported the extraction of pectin from new raw materials and using different extraction conditions, which influence the yield and quality of the final product, and may improve the rheological properties. This review describes the structure, sources, applications and industrial extraction processes, as well as the analysis methods of physicochemical characterization of pectin.

  5. 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.

  6. Effect of Quantity of Low–Methoxyl Pectin on Physical Properties of Freeze–Dried Strawberry Jellies

    Directory of Open Access Journals (Sweden)

    Ciurzyńska Agnieszka

    2015-12-01

    Full Text Available The development of fruit-based products with a high proportion of fruit and good nutritional, sensory and functional properties may help to diversify market supply. These products ought to be attractive, especially to young people, easy to consume and have a reasonably long shelf life. Three recipes of freeze-dried strawberry jelly with low-methoxyl pectin (LMP (2.0, 2.5, 3.5% LMP with the use of strawberry pulp were obtained and physical properties were investigated to choose the sample with the best quality factors. The quantity of added low-methoxyl pectin influences the physical properties of freeze-dried strawberry jellies. The recipe with 2.5% addition of low-methoxyl pectin was chosen based on the results obtained. Despite the relatively high friability and low hardness, and higher shrinkage, it has a fast rate of rehydration. It is also characterised by high porosity and the parameters of the colour most similar to the raw material and low water content and activity.

  7. Characterization of natural low-methoxyl pectin from sunflower head extracted by sodium citrate and purified by ultrafiltration.

    Science.gov (United States)

    Kang, Jiaqi; Hua, Xiao; Yang, Ruijin; Chen, Ying; Yang, Hui

    2015-08-01

    Sunflower head pectin was extracted by 0.6% (w/v) sodium citrate under 85°C, 3.5h with a solid to liquid ratio of 1:40, giving the maximum uronic acid yield of 16.90% (w/w). The extract was purified by an ultrafiltration membrane with the molecular weight cut-off of 8000 Da and dried by spray-drying to obtain SFHP(A) powders with particle diameters of 2-5 μm. In comparison to the SFHP(B) extracted by ammonium oxalate and isolated by alcohol, SFHP(A) had a close DM (22.56%) but a considerably lower DAm (3.42%). HPSEC-MALLS analysis suggested that SFHP(A) has undergo a deeper degradation resulting in smaller Mw and Mn. HPAEC-PAD showed that SFHP(A) contains more neutral sugars since the degraded RG fragments have been retained during ultrafiltration. Finally, pectin aggregation in aqueous was investigated by FEG-SEM, which reveals that pectin network structure is constructed by microfilaments via coiling, intertwining and crosslinking.

  8. Evaluation of folic acid release from spray dried powder particles of pectin-whey protein nano-capsules.

    Science.gov (United States)

    Assadpour, Elham; Jafari, Seid-Mahdi; Maghsoudlou, Yahya

    2017-02-01

    Our main goal was to evaluate release kinetics of nano-encapsulated folic acid within a double W1/O/W2 emulsion. First, W1/O nano-emulsions loaded with folic acid were prepared and re-emulsified into an aqueous phase (W2) containing single whey protein concentrate (WPC) layer or double layer complex of WPC-pectin to form W1/O/W2 emulsions. Final double emulsions were spray dried and their microstructure was analyzed in terms of scanning electron microscopy (SEM), and Fourier Transform Infrared spectroscopy (FTIR). Also the release trends of folic acid were determined and fitted with experimental models of zero and first order, Higuchi, and Hixson-Crowell. It was revealed that folic acid nano-capsules made with Span as the surfactant had the lowest release rate in acidic conditions (pH=4) and highest release in the alkaline conditions (pH=11). The best model fitting for folic acid release data was observed for single layer WPC encapsulated powders with the highest R(2). Our FTIR data showed there was no chemical interaction between WPC and pectin in double layered capsules and based on SEM results, single WPC layered capsules resulted in smooth and uniform particles which by incorporating pectin, some wrinkles and shrinkage were found in the surface of spray dried powder particles.

  9. Air plasma or UV-irradiation applied to surface modification of pectin/poly(vinyl alcohol) blends

    Science.gov (United States)

    Kowalonek, Jolanta; Kaczmarek, Halina; Dąbrowska, Aldona

    2010-10-01

    Poly(vinyl alcohol), pectin and their blends with different components ratio were exposed to low-temperature air plasma or high energy UV-irradiation ( λ = 254 nm) for the purpose of surface modification. The physico-chemical changes in surface properties have been studied by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and contact angle measurements. Surface free energy of polymeric films, its polar and dispersive components have been calculated by Owens-Wendt method. Moreover, the work of adhesion was estimated and the recovery of hydrophobic properties of modified films after storage have been also studied. The few seconds air-plasma treatment caused more effective surface modification than 5-6 h UV-irradiation. The observed changes were partially reversible, contrary to these caused by photo-modification. It was found that pectin/PVA (50:50) blend was characterised by larger susceptibility to plasma modification compared to pure pectin and pure PVA, whereas the photosensitivity to radiation of 254 nm wavelength was the lowest for this specimen in comparison to other studied samples.

  10. Optimization of enzymatic hydrolysis conditions for extraction of pectin from rapeseed cake (Brassica napus L.) using commercial enzymes.

    Science.gov (United States)

    Jeong, Han-Seob; Kim, Ho-Yong; Ahn, Sye Hee; Oh, Sei Chang; Yang, In; Choi, In-Gyu

    2014-08-15

    The aims of this study were to extract pectin from rapeseed cake (RSC) by enzymatic hydrolysis using commercial enzymes (Celluclast and Alcalase) and to investigate the effects of different reaction conditions, such as enzymatic hydrolysis time, enzyme-RSC ratio, and Celluclast-Alcalase ratio, on the degradation of RSC and pectin yield. RSC was treated using a combined extraction process that consisted of a fat removal process, enzymatic hydrolysis, and isopropanol/ethanol precipitation. After the fat removal process and enzymatic hydrolysis, defatted-RSC was suitably decomposed, and the loss of liberated reducing sugars was minimized when the hydrolysis condition reached a hydrolysis time of 270 min or an enzyme-RSC ratio of 1:50. Based on these results, various Celluclast-Alcalase ratios were applied. Alcalase led to the destruction of protein-carbohydrate complex in defatted-RSC, whereas Celluclast cleaved some linkages of carbohydrate slightly. As a result, the highest pectin yield was 6.85% at the Celluclast-Alcalase ratio of 1:4.

  11. Combined effects of independent variables on yield and protein content of pectin extracted from sugar beet pulp by citric acid.

    Science.gov (United States)

    Li, De-Qiang; Du, Guang-Ming; Jing, Wei-Wen; Li, Jun-Fang; Yan, Jia-Yu; Liu, Zhi-Yong

    2015-09-20

    The extraction of pectin from sugar beet pulp by citric acid was carried out under different conditions using Box-Behnken design for four independent variables (pH, temperature, time and liquid to solid ratio). The yield of sugar beet pulp pectin ranged from 6.3% to 23.0%, and the content of protein from 1.5% to 4.5%. All independent variables significantly affected the yield, and all variables except liquid to solid ratio significantly affected the protein content. The yield increased as decreasing pH of extracting solution, extending time and advancing temperature, and an opposite relationship of effects between variables and content of protein was obtained. The chemical composition of collected samples was determined. Moreover, from the results of emulsifying properties study, the extracted pectin from sugar beet pulp could prepare steady oil-in-water emulsions. Therefore, it was inferred that the extraction conditions could influence yield and protein content, resulting in different emulsifying property.

  12. Immunolocalization of Arabinogalactan Proteins and Pectins in Floral Buds of Cucumber (Cucumis sativus L.) During Sex Determination

    Institute of Scientific and Technical Information of China (English)

    Yi-Ben PENG; Cheng ZOU; Hua-Qin GONG; Shu-Nong BAI; Zhi-Hong XU; Yi-Qin LI

    2005-01-01

    Arabinogalactan proteins (AGPs) and pectins were detected in the floral buds of cucumber (Cucumis sativus L.) during its sex determination using the following monoclonal antibodies: MAC 207 (recognizes AGP epitopes); JIM 8 (recognizes a subset ofAGP epitopes); and JIM 5 and JIM 7 (epitopes of pectins esterified to various degrees). In the stem apex meristem (SAM) of the cucumber, epitopes of MAC 207, JIM 7, and JIM 5 were localized in the cells from second to third peripheral layers when the sex organ primodium began to differentiate; epitopes of MAC 207 and JIM 5 were also detected in the ragged edge cells. A very dense labeling signal with MAC 207 was observed in the carpel and pistil primodium. The AGP epitopes recognized by JIM 8 were localized in the anther of the male flower and the anther-like portion of the stagnant stamen of the female flower. This suggests that the AGPs and pectins in the SAM of the cucumber are closely associated with the differentiation of the SAM, from meristematic cells to floral primodium. The subset of AGPs recognized by JIM 8 may play an important role in stamen formation.

  13. Preparation and evaluation of electrospun nanofibers containing pectin and time-dependent polymers aimed for colonic drug delivery of celecoxib

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    A. Akhgari

    2016-01-01

    Full Text Available Objective(s:The aim of this study was to prepare electrospun nanofibers of celecoxib using combination of time-dependent polymers with pectin to achieve a colon-specific drug delivery system for celecoxib. Materials and Methods:Formulations were produced based on two multilevel 22 full factorial designs. The independent variables were the ratio of drug:time-dependent polymer (X1 and the amount of pec­tin in formulations (X2. Electrospinning process was used for preparation of nanofibers. The spinning solutions were loaded in 5 mL syringes. The feeding rate was fixed by a syringe pump at 2.0 mL/h and a high voltage supply at range 10-18 kV was applied for electrospinning. Electrospun nanofibers were collected and evaluated by scanning electron microscopy and drug release in the acid and buffer with pH 6.8 with and without pectinase. Results:Electrospun nanofibers of celecoxib with appropriate morphological properties were produced via electrospinning process. Drug release from electrospun nanofibers was very low in the acidic media; while, drug release in the simulated colonic media was the highest from formulations containing pectin. Conclusion: Formulation F2 (containing drug:ERS with the ratio of 1:2 and 10% pectin exhibited acceptable morphological characteristics and protection of drug in the upper GI tract and could be a good candidate as a colonic drug delivery system for celecoxib.

  14. 不同产地野菊花中绿原酸、4,5-二咖啡酰奎尼酸的含量测定%Content Determination of Chlorogenic Acid and 4,5-O-Dicaffeoylquinic Acid in Chrysanthemi Indici Flos from Different Areas

    Institute of Scientific and Technical Information of China (English)

    崔永霞; 吴明侠; 许闽; 王丽果

    2012-01-01

    OBJECTIVE To determine the content of chlorogenic acid and 4,5-O-dicaffeoylquinic acid in Chrysanthemi Indici Flos from different areas. METHODS HPLC was used. The chromatographic separation was performed on a Diamonsil C18(4.6 mm × 250 mm,5 μm) column with gradient elute. The detection wavelength was 327 nm and column temperature was 30℃. RESULTS Good linear relationship between the peak area and content of chlorogenic acid and 4,5-O-dicaffeoylquinic acid was achieved when the amount was within 0.011-0.22 ug,0.0175-0.35 μg; the recoveries were 99.1% and 98.8%; RSD were 1.93% and 1.54%(n=9). CONCLUSION The method is accurate,reproducible and suitable to determine chlorogenic acid and 4,5-O-dicaffeoylquinic acid in Chrysanthemi Indici Flos.%目的 建立不同产地野菊花中绿原酸、4,5-二咖啡酰奎尼酸的含量测定方法.方法 采用HPLC,色谱柱为Diamonsil C18(4.6mm×250 mm,5μm);采用梯度洗脱;检测波长327 nm;柱温30℃;流速1.0 mL·min-1.结果 绿原酸、4,5-二咖啡酰奎尼酸的线性范围分别为0.011~0.22 μg,0.0175~0.35 μg.加样回收率分别为99.1%和98.8%; RSD分别为1.93%和1.54%(n=9).结论 本方法操作简便,分析速度快,结果准确,重复性好,可用于野菊花中绿原酸和4,5-二咖啡酰奎尼酸含量的测定.

  15. Cellulose-Pectin Spatial Contacts Are Inherent to Never-Dried Arabidopsis Primary Cell Walls: Evidence from Solid-State Nuclear Magnetic Resonance.

    Science.gov (United States)

    Wang, Tuo; Park, Yong Bum; Cosgrove, Daniel J; Hong, Mei

    2015-07-01

    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 (13)C spectra, two-dimensional (13)C-(13)C 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.

  16. Plant-derived pectin nanocoatings to prevent inflammatory cellular response of osteoblasts following Porphyromonas gingivalis infection

    Directory of Open Access Journals (Sweden)

    Meresta A

    2017-01-01

    Full Text Available Anna Meresta,1 Justyna Folkert,1 Timo Gaber,2 Korneliusz Miksch,1 Frank Buttgereit,2 Jacqueline Detert,2 Nicole Pischon,3,* Katarzyna Gurzawska3,4,* 1Environmental Biotechnology Department, Faculty of Power and Environmental, Silesian University of Technology, Gliwice, Poland; 2Department of Rheumatology and Clinical Immunology, 3Department of Periodontology, Charité University Medicine, Berlin, Germany; 4Oral Surgery Department, The School of Dentistry, University of Birmingham, Birmingham, UK *These authors contributed equally to this work Background: Bioengineered plant-derived Rhamnogalacturonan-Is (RG-Is from pectins are potential candidates for surface nanocoating of medical devices. It has recently been reported that RG-I nanocoatings may prevent bacterial infection and improve the biocompatibility of implants. The aim of the study was to evaluate in vitro impact of bioengineered RG-I nanocoatings on osteogenic capacity and proinflammatory cytokine response of murine osteoblasts following Porphyromonas gingivalis infection.Methods: Murine MC3T3-E1 osteoblasts and isolated primary calvarial osteoblasts from C57BL/6J (B6J osteoblasts mice were infected with P. gingivalis and incubated on tissue culture polystyrene plates with or without nanocoatings of unmodified RG-Is isolated from potato pulps (PU or dearabinanated RG-Is (PA. To investigate a behavior of infected osteoblasts cultured on RG-Is cell morphology, proliferation, metabolic activity, mineralization and osteogenic and pro-inflammatory gene expression were examined.Results: Following P. gingivalis infection, PA, but not PU, significantly promoted MC3T3-E1 and BJ6 osteoblasts proliferation, metabolic activity, and calcium deposition. Moreover, Il-1b, Il-6, TNF-α, and Rankl gene expressions were downregulated in cells cultured on PU and to a higher extent on PA as compared to the corresponding control, whereas Runx, Alpl, Col1a1, and Bglap gene expressions were upregulated vice

  17. Management of predictable pain using fentanyl pectin nasal spray in patients undergoing radiotherapy

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    Bell BC

    2013-12-01

    Full Text Available Brent C Bell, E Brian Butler Department of Radiation Oncology, Houston Methodist Hospital, The Texas Medical Center, Houston, TX, USA Background: Studies report the need for improved pain management in the radiation oncology setting. Many patients with well controlled background pain experience breakthrough pain in cancer (BTPc that can interrupt their treatment schedule with a potentially negative impact on outcomes. BTPc can be unpredictable and predictable; both types of pain can be managed with fast-acting analgesics, but predictable pain lends itself to anticipatory management. Methods: Five consecutive cases are described in which fentanyl pectin nasal spray (FPNS was used to manage BTPc, with an emphasis on the anticipatory management of predictable pain in cancer patients receiving radiotherapy. Results: Patients (four men, one woman, age range 32–84 years, were diagnosed with various cancers. All patients were receiving opioid treatment for chronic pain, and experienced predictable pain with radiotherapy which included pain associated with lying on a treatment table for a sustained time during an average of 29 radiotherapy treatments; pain associated with radiation simulation and radiotherapy; pain associated with odynophagia related to increasing mucositis during treatment, resulting in decreased nutritional intake; pain associated with the customized immobilization mask for head and neck cancer patients; and pain associated with defecation. Some patients also reported pain awakening them randomly at night (eg, sleep interruption. All patients attained lower pain intensity scores (2/10 to 3/10, reduced from approximately 7/10, when they were treated with FPNS 20 minutes before a predictable pain event. No patient experienced any pain-related interruptions to their course of radiotherapy. The average number of radiotherapy sessions was 29 per patient, excluding one short-course treatment for one patient. Conclusion: FPNS offers a good

  18. Orally administered, insulin-loaded amidated pectin hydrogel beads sustain plasma concentrations of insulin in streptozotocin-diabetic rats.

    Science.gov (United States)

    Musabayane, C T; Munjeri, O; Bwititi, P; Osim, E E

    2000-01-01

    We report successful oral administration of insulin entrapped in amidated pectin hydrogel beads in streptozotocin (STZ)-diabetic rats, with a concomitant reduction in plasma glucose concentration. The pectin-insulin (PI) beads were prepared by the gelation of humilin-pectin solutions in the presence of calcium. Separate groups of STZ-diabetic rats were orally administered two PI beads (30 micrograms insulin) once or twice daily or three beads (46 micrograms) once daily for 2 weeks. Control non-diabetic and STZ-diabetic rats were orally administered pectin hydrogel drug-free beads. By comparison with control non-diabetic rats, untreated STZ-diabetic rats exhibited significantly low plasma insulin concentration (0.32+/-0. 03 ng/ml, n=6, compared with 2.60+/-0.44 ng/ml in controls, n=6) and increased plasma glucose concentrations (25.84+/-1.44 mmol/l compared with 10.72+/- 0.52 mmol/l in controls). Administration of two PI beads twice daily (60 micrograms active insulin) or three beads (46 micrograms) once a day to STZ-diabetic rats increased plasma insulin concentrations (0.89+/-0.09 ng/ml and 1.85+/- 0.26 ng/ml, respectively), with a concomitant reduction in plasma glucose concentration (15.45+/-1.63 mmol/l and 10.56+/-0.26 mmol/l, respectively). However, a single dose of PI beads (30 micrograms) did not affect plasma insulin concentrations, although plasma glucose concentrations (17.82+/-2.98 mmol/l) were significantly reduced compared with those in untreated STZ-diabetic rats. Pharmacokinetic parameters in STZ-diabetic rats show that the orally administered PI beads (30 micrograms insulin) were more effective in sustaining plasma insulin concentrations than was s.c. insulin (30 micrograms). The data from this study suggest that this insulin-loaded amidated pectin hydrogel bead formulation not only produces sustained release of insulin, but may also reduce plasma glucose concentration in diabetes mellitus.

  19. Tomato fruit cell wall : I. Use of purified tomato polygalacturonase and pectinmethylesterase to identify developmental changes in pectins.

    Science.gov (United States)

    Koch, J L; Nevins, D J

    1989-11-01

    Cell wall isolation procedures were evaluated to determine their effect on the total pectin content and the degree of methylesterification of tomato (Lycopersicon esculentum L.) fruit cell walls. Water homogenates liberate substantial amounts of buffer soluble uronic acid, 5.2 milligrams uronic acid/100 milligrams wall. Solubilization appears to be a consequence of autohydrolysis mediated by polygalacturonase II, isoenzymes A and B, since the uronic acid release from the wall residue can be suppressed by homogenization in the presence of 50% ethanol followed by heating. The extent of methylesterification in heat-inactivated cell walls, 94 mole%, was significantly greater than with water homogenates, 56 mole%. The results suggest that autohydrolysis, mediated by cell wall-associated enzymes, accounts for the solubilization of tomato fruit pectin in vitro. Endogenous enzymes also account for a decrease in the methylesterification during the cell wall preparation. The heat-inactivated cell wall preparation was superior to the other methods studied since it reduces beta-elimination during heating and inactivates constitutive enzymes that may modify pectin structure. This heat-inactivated cell wall preparation was used in subsequent enzymatic analysis of the pectin structure. Purified tomato fruit polygalacturonase and partially purified pectinmethylesterase were used to assess changes in constitutive substrates during tomato fruit ripening. Polygalacturonase treatment of heat-inactivated cell walls from mature green and breaker stages released 14% of the uronic acid. The extent of the release of polyuronides by polygalacturonase was fruit development stage dependent. At the turning stage, 21% of the pectin fraction was released, a value which increased to a maximum of 28% of the uronides at the red ripe stage. Pretreatment of the walls with purified tomato pectinesterase rendered walls from all ripening stages equally susceptible to polygalacturonase. Quantitatively

  20. 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.

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    Clare L Adam

    Full Text Available 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.