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1
Pedrolli, Danielle Biscaro y Eleonora Cano Carmona. "Purification and Characterization of a Unique Pectin Lyase from Aspergillus giganteus Able to Release Unsaturated Monogalacturonate during Pectin Degradation". Enzyme Research 2014 (31 de diciembre de 2014): 1–7. http://dx.doi.org/10.1155/2014/353915.
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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.
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Chandrayan, Puja. "Biological Function(s) and Application (s) of Pectin and Pectin Degrading Enzymes". Biosciences, Biotechnology Research Asia 15, n.º 1 (25 de marzo de 2018): 87–100. http://dx.doi.org/10.13005/bbra/2611.
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Pectin is an integral part of plant cell wall and since centuries pectin extracted from plants is widely used in food and fruit juice processing. Moreover, in last half century, the applications have also invaded into many bio-processing applications such as pharmaceutical, bioenergy, textile, paper and tea processing. In these growing industries, the use of pectinases has grown with a significant amount i.e. approximately 10 % of total global enzyme market comes from pectinases. Herein comprehensive analyses of information related to structure and function of pectin in plant cell wall as well as structural classes of pectins have been discussed. The major function of pectin is in cementing the cellulose and hemicelluloses network, cell-cell adhesion and plant defence. Keeping the wide use of pectin in food industry and growing need of environment friendly technology for pectin extraction has accelerated the demand of pectin degrading enzymes (PDEs). PDEs are from three enzyme classes: carbohydrate esterases from CE8 and CE12 family, glycoside hydrolases from GH28 family and lyases from PL1, 2, 3, 9 and 10. We have reviewed the literature related to abundance and structure-function of these abovementioned enzymes from bacteria. From the current available literature, we found very limited information is present about thermostable PDEs. Hence, in future it could be a topic of study to gain the insight about structure-function of enzymes together with the expanded role of thermostable enzymes in development of bioprocesses based on these enzymes.
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Nakagawa, Tomoyuki, Kaichiro Yamada, Shuki Fujimura, Takashi Ito, Tatsuro Miyaji y Noboru Tomizuka. "Pectin utilization by the methylotrophic yeast Pichia methanolica". Microbiology 151, n.º 6 (1 de junio de 2005): 2047–52. http://dx.doi.org/10.1099/mic.0.27895-0.
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The methylotrophic yeast Pichia methanolica was able to grow on pectic compounds, pectin and polygalacturonate, as sole carbon sources. Under the growth conditions used, P. methanolica exhibited increased levels of pectin methylesterase, and pectin-depolymerizing and methanol-metabolizing enzyme activities. On the other hand, P. methanolica has two alcohol oxidase (AOD) genes, MOD1 and MOD2. On growth on pectin, the P. methanolica mod1Δ and mod1Δmod2Δ strains showed a severe defect in the growth yield, although the mod2Δ strain could grow on polygalacturonate to the same extent as the wild-type strain. The expression of MOD1 was detected in pectin-grown cells, but the MOD2-gene expression detected by pectin was much lower than that of MOD1. Moreover, pectin could induce peroxisome proliferation in P. methanolica, like methanol and oleic acid. These findings showed that P. methanolica was able to utilize the methylester moiety of pectin by means of methanol-metabolic enzymes in peroxisomes, and that the functional AOD subunit for pectin utilization was Mod1p in P. methanolica.
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Takasawa, Toshihide, Keiko Sagisaka, Koichi Yagi, Kyoko Uchiyama, Atsushi Aoki, Kyo Takaoka y Katsuhiro Yamamato. "Polygalacturonase isolated from the culture of the psychrophilic fungus Sclerotinia borealis". Canadian Journal of Microbiology 43, n.º 5 (1 de mayo de 1997): 417–24. http://dx.doi.org/10.1139/m97-059.
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A polygalacturonase was isolated from the culture medium of Sclerotinia borealis, a psychrophilic fungus that grows on lawn and wheat seedling under the snow in winter and induces the snow mold disease. Pectic acid was a better substrate of this enzyme than pectin when the activity was determined by measuring the reducing sugar produced. However, when the activity was measured by viscosity change, the viscosity of pectin decreased more rapidly than that of pectic acid. The results of viscosity change apparently indicate that the polygalacturonase catalyzes pectin hydrolysis as an endo-type enzyme. Highly methyl-esterified pectin was a poor substrate, as determined by measurements of reducing sugar production and viscosity change. It is suggested from the results that the methoxy group of pectin affects the polygalacturonase reaction. A reaction mechanism was proposed for the polygalacturonase reaction. Molecular mass of this enzyme was 40 kDa and its isoelectric point was pH 7.5. Optimum pH of the enzyme reaction was 4.5 and its optimum temperature was 40–50 °C. Thirty percent of the maximum activity was observed at 5 °C, but it was only slightly active above 60 °C. The activity was preserved for more than 2 years at 5 °C and pH 4.5, but it was lost when kept at room temperature overnight or heated at 50 °C for 30 min. The amino acid sequence of the N-terminal region of the psychrophilic polygalacturonase of Sclerotinia borealis is compared with those of polygalacturonases of mesophilic fungi. The function of this enzyme against the target plants is discussed with reference to the reaction of polygalacturonases of mesophilic fungi.Key words: polygalacturonase, pectin-hydrolyzing enzyme, psychrophilic fungi, snow mold disease, Sclerotinia borealis.
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Widowati, Esti, Ardhea Mustika Sari y Rokhimah Sudarmi Ningsih. "KOMBINASI ENZIM POLIGALAKTURONASE DAN ENZIM PEKTINESTERASE PADA KLARIFIKASI SARI BUAH NAGA SUPER MERAH (Hylocereus Costaricensis) DALAM PEMBUATAN SIRUP". Jurnal Teknologi Hasil Pertanian 12, n.º 1 (19 de febrero de 2020): 29. http://dx.doi.org/10.20961/jthp.v12i1.37625.
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<em>The aim of this research was to investigated the effect of polygalacturonase enzyme (PG) from Bacillus licheniformis strain GD2a AR2 0.09%, 0.1%, and 0.11% concentration combine with pectinesterase enzyme (PE) from Bacillus licheniformis strain GD2a KK2 0.5%, 1%, and 1.5% concentration on the super red dragon fruit juice calrification in syrup production based in pH, total soluble solids, transmittance, and viscosity. Polygalacturonase enzyme hydrolized the α-1,4- D-glycosidic form galacturonic acid while the pectinesterase enzyme break the metoxyl group of pectin form pectat acid. Both PG and PE work together to hydrolized pectin. Pectinesterase catalyzed pectin become pectat acid as the substrat for polygalacturonase. In the lower acid degree, polygalcturonase and pectinesterase enzyme combination cause the viscosity and total soluble solids decrease. Degradation of pectin cause the transmittance of super red dragon fruit syrup increase. The result of this research were obtained a partially pure polygalacturonase enzyme with enzyme activity 0.31 U/ml while the pectinesterase enzyme activity was 1.167 U/ml. Samples with the addition 0.11% concentration of poligalakturonase enzyme and 0.5% concentration of pectinesterase enzyme with pH value of 4.303, total soluble solid value of 38.133<sup>o</sup>Brix, transmittance value of 74.5%T, and viscocity value of 0.128cP was selected sample. </em>
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Fissore, E. N., N. M. Ponce, C. A. Stortz, A. M. Rojas y L. N. Gerschenson. "Characterisation of Fiber Obtained from Pumpkin (cucumis moschata duch.) Mesocarp Through Enzymatic Treatment". Food Science and Technology International 13, n.º 2 (abril de 2007): 141–51. http://dx.doi.org/10.1177/1082013207077914.
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Cell wall-enriched pumpkin ( Cucumis moschata Duch.) powder was submitted to enzymatic hydrolysis by cellulase or hemicellulase in order to evaluate the performance of these cell wall-degrading enzymes on that substrate. Different enzyme-substrate ratios were evaluated and the effect exerted by the buffer on cell wall polysaccharides. Cellulase produced the release of pectin macromolecules which include homogalacturonans side chains, the rhamnogalacturonan I core and rhamnogalacturonan II, in conjunction with xylogalacturonans. The content of galacturonic acid in product obtained ranged from 545 to 781 g/kg of fiber. Hemicellulases produced intense pectin hydrolysis leading to fiber-fractions with galacturonic acid contents ranging from 390 to 444 g/kg of fiber and enriched in glucose polymers as the enzyme proportion increased. Few rhamnogalacturonan-I was present.The acidic citrate buffer (pH 5.2) used for allowing enzyme activity could per se remove noncovalent cross-links like ionic bonds. As a consequence, pectin-in-extensin entanglements, pectins joined by Ca2+-bridges through the homogalacturonan side chains, and some pectins that are originally soluble in cold water due to little or no binding to the cell wall, could be removed by this citrate buffer. Enzymatic hydrolysis as well as buffer extraction produced fiber-products with an important thickening effect of aqueous systems. This effect was smaller as the ratio enzyme-substrate was increased and, in general, the fiber fractions isolated produced an in vitro glucose diffusion retardation.
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Leone, G. y J. Van den Heuvel. "Regulation by carbohydrates of the sequential in vitro production of pectic enzymes by Botrytis cinerea". Canadian Journal of Botany 65, n.º 10 (1 de octubre de 1987): 2133–41. http://dx.doi.org/10.1139/b87-294.
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Cultures of Botrytis cinerea in a basal salt medium supplemented with different pectin-related polysaccharides (French bean cell walls; citrus pectin; sodium polygalacturonate) as the only carbon source were examined daily for polygalacturonase activity, type of pectic enzymes present, and mycelial growth. Total polygalacturonase activity and number of enzymes detectable were influenced by type and concentration of the substrate and by the conidial concentration at which the cultures were started. A consistent sequence in the production of pectic enzymes was found. The polygalacturonase PG2 was always the first enzyme present in the culture filtrates and was followed by a number of polygalacturonase and pectinesterase isoenzymes. PG2 was also found in ungerminated conidia. Its production is the expression of a constitutive gene as it was independent of the presence of the substrate and strictly correlated with fungal growth. D-Galacturonic acid at 2 mM induced the production of some of the pectic enzymes. At 10 mM and above, however, it repressed PG2 and the subsequent production of the whole pectic isoenzyme complex, indicating a feedback repression. The results suggest that the pectic isoenzymes produced by B. cinerea constitute a coordinated catabolic pathway for the complete degradation of pectic polysaccharides.
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Huang, Cian-Song, Qiao-Lin Li, Diana Lo, Yuh-Tai Wang y Ming-Chang Wu. "Anti-inflammatory activity of pectic enzyme-treated pectin on lipopolysaccharide-induced RAW 264.7 cells". Journal of Functional Food and Nutraceutical 1, n.º 1 (21 de agosto de 2019): 23–30. http://dx.doi.org/10.33555/jffn.v1i1.14.
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The purpose of this study was to investigate the ability and pathway of the pectic enzyme-treated (PET) pectin to inhibit the inflammation of macrophage RAW 264.7 induced by lipopolysaccharide. Results showed that PET-pectin produced from 1% substrate and 48 h reaction time had the highest antioxidative activity, thus these parameters were used to produce PET-pectin used in this study. PET-pectin showed no cell cytotoxicity to normal macrophage RAW 264.7 and reduce the nitrite secretion from LPS-induced RAW 264.7 by 20%. Finally, the expression of cytokines, including NO synthase (iNOS), nitric oxide (NO), cyclooxygenase-2 (COX-2), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and tumor necrosis factor (TNF-α) were analyzed by western blot. In the western blot method, it was found that iNOS, COX-2, NF-κB, TNF-α and other proteins that activated NO production had a downtrend. It was found that PET-pectin possess promising activity to mitigate the inflammatory response.
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Yuan, Ye, Xin-Yu Zhang, Yan Zhao, Han Zhang, Yi-Fa Zhou y Juan Gao. "A Novel PL9 Pectate Lyase from Paenibacillus polymyxa KF-1: Cloning, Expression, and Its Application in Pectin Degradation". International Journal of Molecular Sciences 20, n.º 12 (22 de junio de 2019): 3060. http://dx.doi.org/10.3390/ijms20123060.
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Pectate lyases play an important role in pectin degradation, and therefore are highly useful in the food and textile industries. Here, we report on the cloning of an alkaline pectate lyase gene (pppel9a) from Paenibacillus polymyxa KF-1. The full-length gene (1350 bp) encodes for a 449-residue protein that belongs to the polysaccharide lyase family 9 (PL9). Recombinant PpPel9a produced in Escherichia coli was purified to electrophoretic homogeneity in a single step using Ni2+-NTA affinity chromatography. The enzyme activity of PpPel9a (apparent molecular weight of 45.3 kDa) was found to be optimal at pH 10.0 and 40 °C, with substrate preference for homogalacturonan type (HG) pectins vis-à-vis rhamnogalacturonan-I (RG-I) type pectins. Using HG-type pectins as substrate, PpPel9a showed greater activity with de-esterified HGs. In addition, PpPel9a was active against water-soluble pectins isolated from different plants. Using this lyase, we degraded citrus pectin, purified fractions using Diethylaminoethyl (DEAE)-sepharose column chromatography, and characterized the main fraction MCP-0.3. High-performance gel permeation chromatography (HPGPC) analysis showed that the molecular mass of citrus pectin (~230.2 kDa) was reduced to ~24 kDa upon degradation. Ultra-performance liquid chromatography - tandem mass spectrometer (UPLC-MS) and monosaccharide composition analyses demonstrated that PpPel9a worked as an endo-pectate lyase, which acted primarily on the HG domain of citrus pectin. In vitro testing showed that the degradation product MCP-0.3 significantly promotes the growth of Lactobacillus plantarum and L. rhamnosus. In this regard, the enzyme has potential in the preparation of pharmacologically active pectin products.
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Pieczywek, Piotr Mariusz, Justyna Cybulska y Artur Zdunek. "An Atomic Force Microscopy Study on the Effect of β-Galactosidase, α-l-Rhamnosidase and α-l-Arabinofuranosidase on the Structure of Pectin Extracted from Apple Fruit Using Sodium Carbonate". International Journal of Molecular Sciences 21, n.º 11 (5 de junio de 2020): 4064. http://dx.doi.org/10.3390/ijms21114064.
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The enzyme driven changes in plant cell wall structure during fruit ripening result in debranching, depolymerization and solubilization of pectin polysaccharides, which has an effect in terms of the postharvest quality losses in fruit. Atomic force microscopy (AFM) has revealed that diluted alkali soluble pectins (DASP) from fruit and vegetables have an interesting tendency to self-assemble into regular structures. However, the mechanism is not yet fully understood. The current study is aimed at investigating the role of neutral sugars, namely galactose, rhamnose and arabinose in the formation of the branched structure of DASP. β-galactosidase, α-l-rhamnosidase and α-l-arabinofuranosidase enzymes were used for the treatment of DASP extracted from Golden Delicious apple flesh (Malus domestica cv. Golden Delicious). The effects of the selective degradation of pectic polysaccharides after 15, 30, 60, 90 and 120 min of incubation were observed using AFM. The α-l-rhamnosidase enzyme activity on pectin extracted with Na2CO3 did not cause any visible or measurable degradation of the molecular structure. The moderate effects of β-galactosidase enzymatic treatment suggested the possible role of galactose in the branching of DASP molecules deposited on mica. Data obtained for α-l-arabinofuranosidase indicated the crucial role of arabinose in the formation and preservation of the highly branched structure of the DASP fraction.
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Pardo, C., M. A. Lapeña y M. Gacto. "Purification and characterization of an extracellular exopolygalacturonase from Geotrichum lactis". Canadian Journal of Microbiology 37, n.º 12 (1 de diciembre de 1991): 974–77. http://dx.doi.org/10.1139/m91-168.
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Geotrichum lactis ATCC 48590 produced extracellular polygalacturonase (EC 3.2.1.67) in media containing pectate, pectin, or galacturonic acid as inducers. The synthesis of the enzyme was strongly repressed by glucose. The polygalacturonase was purified 80-fold by ammonium sulphate precipitation, Sephadex G-100 filtration, and DEAE Sephadex ion-exchange chromatography. Polyacrylamide gel electrophoresis with copolymerized substrate indicated that the isolated material was a single enzyme with polygalacturonase activity. The main product of enzyme action was galacturonic acid. The enzyme shows a molecular weight close to 53 000 by gel filtration and degrades preferentially de-esterified substrates. Km values for pectate and pectin (64% esterified) were 0.09 and 0.49 mg mL−1, respectively. The optimum pH for enzyme activity was 5.0, while the optimum temperature was 40 °C. The polygalacturonase was precipitated by concanavalin A – Sepharose, and treatment with endoglycosidase H reduced its precipitation by the lectin, suggesting that the enzyme is a glycoprotein. In addition to being found extracellularly, the polygalacturonase is also present in the periplasm of the cells. A different form of the polygalacturonase showing a lower molecular weight was located inside the cells. Key words: polygalacturonase, pectic enzymes, Geotrichum lactis.
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Tasgin, Esen, Aynur Babagil, Hayrunnisa Nadaroglu y Patricia E. Allegretti. "Immobilization of Purified Pectin Lyase from Acinetobacter calcoaceticus onto Magnetic Carboxymethyl Cellulose Nanoparticles and Its Usability in Food Industry". Journal of Chemistry 2020 (29 de septiembre de 2020): 1–12. http://dx.doi.org/10.1155/2020/4791408.
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An important component of the pectinase enzyme complex is pectin lyase (polymethylgalacturonate lyase; EC 4.2.2.10). In this study, extracellular pectin lyase enzyme was produced from Acinetobacter calcoaceticus bacteria. Pectin lyase was then purified using three-phase precipitation (TPP) technique with 25.5% yield. The pectin lyase was immobilized covalently via the L-glutaraldehyde spacer to the carboxymethyl cellulose. The immobilized pectin lyase was magnetized using Fe3O4 nanoparticles. Purified pectin lyase was connected to magnetized support material after 90 min at the rate of 80%. The most appropriate immobilization conditions were determined as pH 8 and 30°C. By characterizing the free and immobilized enzyme, KM, Vmax, and optimum pH and optimum temperature values were determined. It was optimum pH 8 and temperature 50°C for both free and immobilized pectin lyase. The structural characterization of the immobilized pectin lyase modified with Fe3O4 nanoparticles was carried out by SEM, FT-IR, and XRD chromatographic analyses. At the end of the study, free and immobilized enzymes were used for purification of some fruit juices and results were compared.
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Soriano, Margarita, Pilar Diaz y Francisco I. Javier Pastor. "Pectate lyase C from Bacillus subtilis: a novel endo-cleaving enzyme with activity on highly methylated pectin". Microbiology 152, n.º 3 (1 de marzo de 2006): 617–25. http://dx.doi.org/10.1099/mic.0.28562-0.
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The gene yvpA from Bacillus subtilis was cloned and expressed in Escherichia coli. It encoded a pectate lyase of 221 amino acids that was denominated PelC. The heterologously expressed enzyme was purified by His-tag affinity chromatography and characterized. PelC depolymerized polygalacturonate and pectins of methyl esterification degree from 22 % to 89 %, exhibiting maximum activity on 22 % esterified citrus pectin. It showed an absolute Ca2+ requirement and the optimum temperature and pH were 65 °C and pH 10, respectively. The deduced amino acid sequence of PelC showed 53 % identity to pectate lyase PelA from Paenibacillus barcinonensis, which was also characterized. Similarly to PelC, purified PelA showed activity on polygalacturonate and pectins with a high degree of methyl esterification. The two enzymes cleaved pectic polymers to a mixture of oligogalacturonates, indicating an endo mode of action. Analysis of activity on trigalacturonate showed that PelC cleaved it to galacturonic acid and unsaturated digalacturonate, whereas PelA did not show activity on this substrate. PelC and PelA showed high homology to a few recently identified pectate lyases of family 3 and form with them a cluster of small-sized pectate lyases from non-pathogenic micro-organisms.
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Wikiera, Agnieszka, Maja Grabacka, Łukasz Byczyński, Bożena Stodolak y Magdalena Mika. "Enzymatically Extracted Apple Pectin Possesses Antioxidant and Antitumor Activity". Molecules 26, n.º 5 (6 de marzo de 2021): 1434. http://dx.doi.org/10.3390/molecules26051434.
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The biological activity of apple pectin extracted conventionally or enzymatically using endo-xylanase and endo-cellulase, was tested in vitro. The analyses were performerd in tetraplicates and the statistical significance of the differences were assessed using ANOVA, Tukey post hoc and LSD (the least significant difference) tests. Multivariate regression analysis was applied to determine the structural components that have a crucial importance for antioxidant and antitumor properties of pectins. The pectins extracted by enzymes contained up to four times more ferulic acid and showed twice as great ability to neutralize free radicals and Fe(III) reduction. The antiradical potential positively correlated with phenols, fucose and rhamnose content. In the assays performed on HT-29 human adenocarcinoma and B16F10 melanoma cell cultures, the “green” pectins, contrary to acid isolated ones, exhibited remarkable anti-neoplastic potential while being nontoxic to nontransformed L929 cell line. The pectins in the dose of 1 mg/mL were capable of inhibiting adhesion (max 23.1%), proliferation (max 40.4%), invasion (max 76.9%) and anchorage-independent growth (max 90%) of HT-29 cells (significance level p < 0.001). These pectin preparations were slightly less active towards B16F10 cells. The enzyme-isolated apple pectins may be useful as a functional food additive and an ingredient of the ointment formulas for post-surgical melanoma treatment.
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Teller, David C., Craig A. Behnke, Kirk Pappan, Zicheng Shen, John C. Reese, Gerald R. Reeck y Ronald E. Stenkamp. "The structure of rice weevil pectin methylesterase". Acta Crystallographica Section F Structural Biology Communications 70, n.º 11 (25 de octubre de 2014): 1480–84. http://dx.doi.org/10.1107/s2053230x14020433.
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Rice weevils (Sitophilus oryzae) use a pectin methylesterase (EC 3.1.1.11), along with other enzymes, to digest cell walls in cereal grains. The enzyme is a right-handed β-helix protein, but is circularly permuted relative to plant and bacterial pectin methylesterases, as shown by the crystal structure determination reported here. This is the first structure of an animal pectin methylesterase. Diffraction data were collected to 1.8 Å resolution some time ago for this crystal form, but structure solution required the use of molecular-replacement techniques that have been developed and similar structures that have been deposited in the last 15 years. Comparison of the structure of the rice weevil pectin methylesterase with that fromDickeya dandantii(formerlyErwinia chrysanthemi) indicates that the reaction mechanisms are the same for the insect, plant and bacterial pectin methylesterases. The similarity of the structure of the rice weevil enzyme to theEscherichia colilipoprotein YbhC suggests that the evolutionary origin of the rice weevil enzyme was a bacterial lipoprotein, the gene for which was transferred to a primitive ancestor of modern weevils and other Curculionidae. Structural comparison of the rice weevil pectin methylesterase with plant and bacterial enzymes demonstrates that the rice weevil protein is circularly permuted relative to the plant and bacterial molecules.
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Tasgin, Esen, Hayrunnisa Nadaroglu, Aynur Babagil y Nazan Demir. "Immobilization of Purified Pectin Lyase from Pseudomonas putida onto Magnetic Lily Flowers (Lilium candidum L.) Nanoparticles and Applicability in Industrial Processes". Molecules 25, n.º 11 (9 de junio de 2020): 2671. http://dx.doi.org/10.3390/molecules25112671.
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Pectinases are an important class of enzymes distributed in many higher plants and microorganisms. One of these enzymes is pectin lyase which has an important role in industrial applications such as clarification of fruit juices. Pectin lyase was purified with 73% yield from Pseudomonas putida bacteria and was 220.7-fold using three phase precipitation technique. Molecular weight of purified pectin lyase was determined as 32.88 kDa with SDS-polyacrylamide gel electrophoresis. The pectin lyase was immobilized covalently via the L-glutaraldehyde spacer to the cellulosic structures of lily flowers (Lilium candidum L.). The immobilized enzyme was then magnetized by modifying with γ-Fe3O4 nanoparticles and determined the most appropriate immobilization conditions as pH 6 and 30 °C. Purified pectin lyase was connected to magnetized support material after 60 min at the rate of 86.4%. The optimum pH and temperatures for the free and immobilized pectin lyase was found to be 6.0 and 40 °C. pH and thermal stabilities of the free and immobilized pectin lyase enzyme have been preserved at high-low temperatures and pH. The structural characterization of the immobilized pectin lyase was performed by SEM, FT-IR, and XRD chromatographic analyses and it was observed that the support materials structure was appropriated to immobilization with pectin lyase and to modify with Fe3O4 nanoparticles.
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Talekar, Sachin, Shamraja Nadar, Asavari Joshi y Gandhali Joshi. "Pectin cross-linked enzyme aggregates (pectin-CLEAs) of glucoamylase". RSC Adv. 4, n.º 103 (2014): 59444–53. http://dx.doi.org/10.1039/c4ra09552a.
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Wongkaew, Malaiporn, Bow Tinpovong, Korawan Sringarm, Noppol Leksawasdi, Kittisak Jantanasakulwong, Pornchai Rachtanapun, Prasert Hanmoungjai y Sarana Rose Sommano. "Crude Pectic Oligosaccharide Recovery from Thai Chok Anan Mango Peel Using Pectinolytic Enzyme Hydrolysis". Foods 10, n.º 3 (16 de marzo de 2021): 627. http://dx.doi.org/10.3390/foods10030627.
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Pectin recovered from mango peel biomass can be used as a potential source for pectic oligosaccharide hydrolysate with excellent probiotic growth-enhancing performance and prebiotic potentials. Consequently, the objectives of the current study were to optimise the enzyme hydrolysis treatment of mango peel pectin (MPP) and to evaluate the pectic oligosaccharide effects of Lactobacillus reuteri DSM 17938 and Bifidobacterium animalis TISTR 2195. Mango of “chok anan” variety was chosen due to its excessive volume of biomass in processing and high pectin content. The optimal treatment for mango peel pectic oligosaccharide (MPOS) valorisation was 24 h of fermentation with 0.3% (v/v) pectinase. This condition provided small oligosaccharides with the molecular weight of 643 Da that demonstrated the highest score of prebiotic activity for both of B. animalis TISTR 2195 (7.76) and L. reuteri DSM 17938 (6.87). The major sugar compositions of the oligosaccharide were fructose (24.41% (w/w)) and glucose (19.52% (w/w)). For the simulation of prebiotic fermentation, B. animalis TISTR 2195 showed higher proliferation in 4% (w/v) of MPOS supplemented (8.92 log CFU/mL) than that of L. reuteri (8.53 CFU/mL) at 72 h of the fermentation time. The main short chain fatty acids (SCFAs) derived from MPOS were acetic acid and propionic acid. The highest value of total SCFA was achieved from the 4% (w/v) MPOS supplementation for both of B. animalis (68.57 mM) and L. reuteri (69.15 mM). The result of this study therefore conclusively advises that MPOS is a novel pectic oligosaccharide resource providing the opportunity for the sustainable development approach through utilising by-products from the fruit industry.
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Kitamoto, Noriyuki y Norihiro Tsukagoshi. "Fungal Pectin Degrading Enzyme Genes." Nippon Nōgeikagaku Kaishi 69, n.º 3 (1995): 369–72. http://dx.doi.org/10.1271/nogeikagaku1924.69.369.
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Nari, J., G. Noat y J. Ricard. "Pectin methylesterase, metal ions and plant cell-wall extension. Hydrolysis of pectin by plant cell-wall pectin methylesterase". Biochemical Journal 279, n.º 2 (15 de octubre de 1991): 343–50. http://dx.doi.org/10.1042/bj2790343.
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The hydrolysis of p-nitrophenyl acetate catalysed by pectin methylesterase is competitively inhibited by pectin and does not require metal ions to occur. The results suggest that the activastion by metal ions may be explained by assuming that they interact with the substrate rather than with the enzyme. With pectin used as substrate, metal ions are required in order to allow the hydrolysis to occur in the presence of pectin methylesterase. This is explained by the existence of ‘blocks’ of carboxy groups on pectin that may trap enzyme molecules and thus prevent the enzyme reaction occurring. Metal ions may interact with these negatively charged groups, thus allowing the enzyme to interact with the ester bonds to be cleaved. At high concentrations, however, metal ions inhibit the enzyme reaction. This is again understandable on the basis of the view that some carboxy groups must be adjacent to the ester bond to be cleaved in order to allow the reaction to proceed. Indeed, if these groups are blocked by metal ions, the enzyme reaction cannot occur, and this is the reason for the apparent inhibition of the reaction by high concentrations of metal ions. Methylene Blue, which may be bound to pectin, may replace metal ions in the ‘activation’ and ‘inhibition’ of the enzyme reaction. A kinetic model based on these results has been proposed and fits the kinetic data very well. All the available results favour the view that metal ions do not affect the reaction through a direct interaction with enzyme, but rather with pectin.
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Glover, H. y CJ Brady. "Pectinesterases From Mature, Unripe Peach Fruit Bind Strongly to Pectic Polysaccharides". Functional Plant Biology 22, n.º 6 (1995): 977. http://dx.doi.org/10.1071/pp9950977.
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Contrary to previous findings, the level of the pectin de-esterifying enzyme, pectinesterase (PE; EC 3.1 .1. 11), is shown to be much higher in mature, green peach fruit than in ripe fruit. Aqueous buffers readily extracted three pectinesterase isoforms from ripe fruit but only a portion of the activity from mature, green fruit. In mature, green fruit extracts the enzyme precipitated when the ionic strength was lowered; consequently isoforms could not be recovered by ion exchange chromatography. In extraction residues from mature, green fruit, residual PE could be measured as active enzyme and, when denatured, could be detected by immunological techniques. Extraction of the enzyme was enhanced after digestion of the tissue with pectin lyase. The extracted enzyme fractionated as a large molecular weight complex rich in uronic acid, rhamnose, galactose and arabinose. After further digestion with endo-β-1,4- galactanase, the enzyme was in two fractions of smaller size but with residual carbohydrate. When mature, green and ripe fruit tissue were co-extracted, the recovered activity was as predicted from independently extracted tissues demonstrating that enzyme activity was not influenced by inhibitors contributed by either tissue type. Isoforms known to be present in the ripe fruit were recovered from extracts of the mixed tissues. It is concluded that PE in extracts of mature, green fruit has a strong association with pectic polymers and this has lead to its underestimation in previous studies. It is suggested that such an association with pectin polymers in vivo may regulate enzyme activity and enzyme turnover.
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Aisien, E. T., E. R. Elaho y F. A. Aisien. "Effects of Linear Alkyl Benzene Sulfonate Detergent on the Activity of Cassava Fermenting Enzyme". Advanced Materials Research 62-64 (febrero de 2009): 258–62. http://dx.doi.org/10.4028/www.scientific.net/amr.62-64.258.
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The effect of linear alkyl benzene sulfonate (LAS) detergent on the activity of cassava fermenting enzymes was investigated for 72 hrs. Enzymatic assay methods were used to determine the activity of cassava fermenting enzymes: cellulase, α-amylase, pectin methyl esterase and phosphorylase. The cassava fermenting media were made up of LAS detergent concentration of between 1g/L to 5g/L. The results show that the LAS detergent of 2g/L and 3g/L gave optimum enzyme activity. The order of enzyme activity was pectin methyl esterase > α-amylase > phosphorylase > cellulase.
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Blumer, J. M., R. P. Clay, C. W. Bergmann, P. Albersheim y A. Darvill. "Characterization of changes in pectin methylesterase expression and pectin esterification during tomato fruit ripening". Canadian Journal of Botany 78, n.º 5 (1 de mayo de 2000): 607–18. http://dx.doi.org/10.1139/b00-035.
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The production, accumulation, and in situ location of pectin methylesterase (EC 3.1.11) was examined in ripening fruit of the processing tomato cv. UC82B. Pectin methylesterase detected with a monoclonal antibody (PME-1) first appeared adjacent to seeds in immature green fruit and was later detected only in tissue adjacent to the cuticle (i.e., exopericarp) during ripening. Enzyme-linked immunosorbant assay and Western blot analysis using PME-1 demonstrated that the fresh-market cultivars Celebrity and Better Boy accumulated lower levels of this immunologically detectable pectin methylesterase during maturation than did processing cv. UC82B, and that the immunologically detected pectin methylesterase and the total detectable pectin methylesterase activities of 'Celebrity' and 'Better Boy' increased throughout ripening. In contrast, processing cv. UC82B displayed a total detectable pectin methylesterase activity profile that peaked during the breaker stage, a finding supported immunologically by tissue-printing. To correlate pectin methylesterase expression during ripening to the degree of methylesterification of pectins in exopericarp cell walls, we subjected exopericarp tissue from 'UC82B' fruit to an immunocytochemical and ultrastructure study. Esterified pectin decreased in some regions of the exopericarp cell walls during fruit development but persisted in some regions as well. Less-esterified pectin was localized in the middle lamella of exopericarp cell walls during preripe stages, while in ripe fruit, this labeling was largely absent.Key words: pectin methylesterase (PME), immunocytochemistry, tissue-print, pectin esterification, Lycopersicon esculentum.
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Degani, Ofir. "Synergism between Cutinase and Pectinase in the Hydrolysis of Cotton Fibers’ Cuticle". Catalysts 11, n.º 1 (9 de enero de 2021): 84. http://dx.doi.org/10.3390/catal11010084.
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Scouring is one of the initial steps in the processing of natural textile fibers (e.g., cotton), performed to remove waxes and pectins, together with spinning oils and other impurities of the plant cell cuticle. Traditional chemical bleaching with boiling NaOH led to harsh removal of the entire fabric’s cuticle waxy layer accompanied by an unwanted alkaline waste. Extracellular lytic enzymes such as lipases, cellulases and pectinases play an essential role in host plant-pathogen interactions. They degrade the plant cuticle and tissue and enable pathogen invasion. Such enzymes, specifically cutinase and pectinase, have been considered potential bio-scouring agents to degrade the cotton fabric cuticle’s outer layer at low temperature and alleviate environmental pollution. In this work, the combined effect of cutinase, pectin lyase, or polygalacturonase on the scouring of cotton fabrics was studied using evaporative light-scattering reverse-phase HPLC and GC-MS analysis of the reaction components, and measuring changes in the cotton fabrics’ properties. The traditional method of cotton fabrics’ scouring with NaOH resulted in decreased pectin content and increased cellulose fibers accessibility, evaluated by specific staining. Treating the cotton fibers’ cuticle with cutinase led to the acidification of the reaction mixture, a decrease in enzyme-specific activity, and elevation in hexadecanoic acid and octadecanoic acids in the reaction fluid. These two saturated fatty acids are the main wax constituents of raw cotton fabrics, identified using GC-MS after dichloromethane reflux overnight. Treating cotton fabrics with each of the three enzymes, cutinase, pectin lyase, or polygalacturonase, increased their pectin removal, as measured by high concentrations of D-galacturonic acid and other pectin constituents in the reaction fluid. A synergistic effect was found in the combined treatment of cutinase and pectin lyase in the hydrolysis of the cotton fibers’ cuticle. This effect was expressed in high water absorbency of the treated fibers, increased fabric weight loss and sharp elevation of a cutin and pectin monomer’s related peaks (retention time [RT] = 4.1 min and 2.9, 4.5 min, respectively). A model was suggested for the synergistic action between cutinase and pectin lyase. It assumes that the cuticle’s digestion by cutinase results in the enlargement and formation of outer layer micropores, which enables the rapid penetration of pectinase into the inner pectin layer.
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Degani, Ofir. "Synergism between Cutinase and Pectinase in the Hydrolysis of Cotton Fibers’ Cuticle". Catalysts 11, n.º 1 (9 de enero de 2021): 84. http://dx.doi.org/10.3390/catal11010084.
Texto completoResumen
Scouring is one of the initial steps in the processing of natural textile fibers (e.g., cotton), performed to remove waxes and pectins, together with spinning oils and other impurities of the plant cell cuticle. Traditional chemical bleaching with boiling NaOH led to harsh removal of the entire fabric’s cuticle waxy layer accompanied by an unwanted alkaline waste. Extracellular lytic enzymes such as lipases, cellulases and pectinases play an essential role in host plant-pathogen interactions. They degrade the plant cuticle and tissue and enable pathogen invasion. Such enzymes, specifically cutinase and pectinase, have been considered potential bio-scouring agents to degrade the cotton fabric cuticle’s outer layer at low temperature and alleviate environmental pollution. In this work, the combined effect of cutinase, pectin lyase, or polygalacturonase on the scouring of cotton fabrics was studied using evaporative light-scattering reverse-phase HPLC and GC-MS analysis of the reaction components, and measuring changes in the cotton fabrics’ properties. The traditional method of cotton fabrics’ scouring with NaOH resulted in decreased pectin content and increased cellulose fibers accessibility, evaluated by specific staining. Treating the cotton fibers’ cuticle with cutinase led to the acidification of the reaction mixture, a decrease in enzyme-specific activity, and elevation in hexadecanoic acid and octadecanoic acids in the reaction fluid. These two saturated fatty acids are the main wax constituents of raw cotton fabrics, identified using GC-MS after dichloromethane reflux overnight. Treating cotton fabrics with each of the three enzymes, cutinase, pectin lyase, or polygalacturonase, increased their pectin removal, as measured by high concentrations of D-galacturonic acid and other pectin constituents in the reaction fluid. A synergistic effect was found in the combined treatment of cutinase and pectin lyase in the hydrolysis of the cotton fibers’ cuticle. This effect was expressed in high water absorbency of the treated fibers, increased fabric weight loss and sharp elevation of a cutin and pectin monomer’s related peaks (retention time [RT] = 4.1 min and 2.9, 4.5 min, respectively). A model was suggested for the synergistic action between cutinase and pectin lyase. It assumes that the cuticle’s digestion by cutinase results in the enlargement and formation of outer layer micropores, which enables the rapid penetration of pectinase into the inner pectin layer.
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Horie, Hideki y Garry A. Rechnitz. "Hybrid tissue/enzyme biosensor for pectin". Analytica Chimica Acta 306, n.º 1 (abril de 1995): 123–27. http://dx.doi.org/10.1016/0003-2670(94)00669-d.
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Markovič, Oskar y Eva Machová. "Immobilization of pectin esterase from tomatoes and Aspergillus foetidus on various supports". Collection of Czechoslovak Chemical Communications 50, n.º 9 (1985): 2021–27. http://dx.doi.org/10.1135/cccc19852021.
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The pectin esterases from tomatoes and Aspergillus foetidus were immobilized by covalent attachment to CNBr-activated Sepharose 4B and by adsorption to polyethylene terephthalate and the properties of the immobilized enzymes were compared. The relative activity of tomato pectin esterase after the immobilization to both supports was almost 7%, whereas the activity of A. foetidus pectin esterase covalently immobilized on CNBr-activated Sepharose 4B was close to 11.5% and a value of almost 23% was measured with the enzyme immobilized by adsorption to polyethylene terephthalate. The pH-optima of both pectin esterases were unchanged after their immobilization, their temperature stability and temperature optimum of activity, however, significantly increased. The differences in the action of free and immobilized pectin esterases were also observed when the final esterification degree of the substrate was compared: the immobilized enzymes, unlike the free pectin esterases, did not act on pectin showing a higher esterification degree. An increase in Km.app which was 5-fold for the tomato pectin esterase and 4-7-fold for the A. foetidus pectin esterase was observed after the immobilization. The immobilization of both pectin esterases on Enzacryl AA which had been activated by diazotization resulted in complete loss of activity; this indicates the role of the residues of tyrosine (and histidine, resp.) in the catalytic action of these enzymes, which has been observed in earlier experiments.
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Wahlström, Kjell, Jan-Olof Karlsson, Ottmar Holdenrieder y Jan Stenlid. "Pectinolytic activity and isozymes in European Armillaria species". Canadian Journal of Botany 69, n.º 12 (1 de diciembre de 1991): 2732–39. http://dx.doi.org/10.1139/b91-343.
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Pectinolytic activities in Armillaria ostoyae, Armillaria mellea, Armillaria gallica, Armillaria borealis, and Armillaria cepistipes were assessed by measuring the ability of fungal strains to reduce the viscosity of their pectic growth media. Isozyme patterns of pectin esterases and polygalacturonases were determined directly from the culture filtrate. A total of 94 strains, representing isolations from various parts of Europe, were analyzed for their isozyme patterns. Armillaria mellea and A. borealis caused a 50% reduction in viscosity within 7 and 9 days, respectively. Growth medium from the other species were slower to reach the 50% level, i.e., means were 13 days for A. ostoyae and 17 days for A. cepistipes and A. gallica. All species produced more isozymes on spruce wood than on citrus pectin medium, and pectic isozyme patterns differed between media. The pectic isozyme pattern for A. mellea differed distinctly from those of the other four species by having two bands of polygalacturonase not found in the others. The pectic isozyme patterns of the other four species were separated using multivariate analysis. The value of such analyses for use in distinguishing between European Armillaria species is discussed, as is the relation between enzyme activity and fungal pathogenicity. Key words: root rot, diagnostic tests, Agaricales, polygalacturonase, pectin esterase.
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Mahmoud, Khaled F., Heba I. Abo-Elmagd y Manal M. Housseiny. "Micro- and nano-capsulated fungal pectinase with outstanding capabilities of eliminating turbidity in freshly produced juice". Food Science and Technology International 24, n.º 4 (22 de enero de 2018): 330–40. http://dx.doi.org/10.1177/1082013217753898.
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The present study aimed to compare the pectinase forms produced from Trichoderma viride—free, micro-capsule, and nano-capsule—in sodium alginate to analyze the pectin that causes the turbidity of orange juice. This was performed along with an estimation of viscosity, residual of pectin, and turbidity. The extracted and purified enzyme was 24.35-fold better than that of the crude enzyme. After application of free one, it loses most of the activity on low degrees of acidity and remains constant on the temperatures of pasteurization. Therefore, the tested enzyme was encapsulated by two different ways using the same polymer. The morphology of the three pectinase forms was obtained by transmission electron microscopy, and the micrographs clearly showed the pores on the surface of sodium alginate matrix after encapsulation. The size of the wall (sodium alginate) ranged from 3.24 to 3.76 µm diameter but was 3.15 µm for core of enzyme. Micro-capsuled and nano-capsuled pectinase can be used in the hydrolysis of pectic substances in orange juice with natural ways and maintaining the quality of final product. Consequently, the cost of juice clarifying can be reduced due to reusing the enzyme several times.
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Çelik, Safinur Yildirim, Nazan Demir, Yaşar Demir, Ahmet Adiguzel y Medine Gulluce. "Production of pectin lyase from Geobacillus pallidus p26, purification, characterization and fruit juice application". Acta Chimica Slovaca 7, n.º 1 (1 de abril de 2014): 57–63. http://dx.doi.org/10.2478/acs-2014-0011.
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Abstract A bacterial strain was isolated from Pasinler hot spring, Erzurum, Turkey. The purified thermophilic isolate was identified as Geobacillus pallidus P26 and used to produce extracellular pectin lyase (EC 4.2.2.10). Pectin lyase enzyme was purified 34 fold by using DEAE-cellulose anion exchange column chromatography and characterized. Molecular weight of the enzyme was determined as 56 kDa by using Sephadex G-100 gel filtration chromatography. Purification of enzyme was verified by SDS-PAGE. The pH- and temperature optima of enzyme were determined (pH 9.0 and 60°C, respectively). Pectin lyase was mostly stable at 50 oC for 24 hours. Its’ activity decreased to 50 % for 24 h at 60°C. KM and Vmax were calculated as 24.8 mg/mL and 2.28 μmol/L min, respectively. Purified pectin lyase was inhibited by Fe3+, Zn2+, Cu2+, Ca2+, Co2+ and Hg2+ but not by Mg2+. The purified pectin lyase enzyme was used for getting fruits juices. It was found that yields of fruits juices increased when they were compared with control.
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Hansen, Karin M., Annette B. Thuesen y Jørgen R. Soderberg. "Enzyme Assay for Identification of Pectin and Pectin Derivatives, Based on Recombinant Pectate Lyase". Journal of AOAC INTERNATIONAL 84, n.º 6 (1 de noviembre de 2001): 1851–54. http://dx.doi.org/10.1093/jaoac/84.6.1851.
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Abstract A simple method was developed for fast identification of pectin, based on a recombinant endopectate lyase cloned from Aspergillus niger. When pectin was demethylated and treated with pectate lyase, β-elimination occurred, resulting in a double bond between C-4 and C-5 in the galacturonic acid residue of the released nonreducing end. The formation of double bonds produced an increase in light absorption, which was detected at 235 nm. The assay was tested on pectin of different origins (apple, orange, sugar beet, sunflower, celery, lemon), pectin derivatives (amidated pectin), and speciality types such as low molecular weight and low %DE (degree of esterification, percentage of galacturonic acid groups esterified with methanol) pectin. The highest response was given by pectate (pectin with %DE<5) and the lowest by pectin extracted from sugar beet. No other gums (carboxymethylcellulose, carrageenan, locust bean gum, tragacanth, gellan, tamarind, xanthan, amylogum, sodium alginate, or agar) gave any response. Members of IPPA (International Pectin Producers Association) have evaluated the validity of the assay in a ring test. All members of the Association were able to identify pectin from other gums in a blind test. The method can replace more laborious and ambiguous identification tests which exist today.
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Mangat, Navjot K. y Jiwan P. Palta. "Inhibition of Polygalacturonase in Tomato Pericarp Tissue by Lysophosphatidylethanolamine: Implications in Fruit Shelf-life". HortScience 30, n.º 4 (julio de 1995): 889A—889. http://dx.doi.org/10.21273/hortsci.30.4.889a.
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The pericarp tissue of red mature tomato (Lycopersicon esculentum cv. Gagliano) was used to exctract polygalacturonase (PG) enzyme. The technique for assaying PG activity involves measurement of released reducing groups that were linked together in pectin. Since the crude extract of PG from pericarp will contain considerable reducing groups, we found that repeated washings of the cell wall pulp removed much of the sugars and thus minimized the background absorbance without loss of PG activity. There is an inherent perplexity concerning the selection of blank for PG assay. This is because (i) the enzyme extract contains both the substrate (pectin) and product (free reducing groups) involved in the reaction; (ii) the color development with cyanoacetamide requires heating for 10 min. Thus, even though the reaction is terminated with borate buffer (pH 9.0) the breakdown of pectin continues chemically by heat; (iii) the absorbance from both pectin and enzyme together at zero time termination was always lower than the sum of absorbances from pectin alone and enzyme alone. This suggests that when together in the same tube, the enzyme appears to protect the pectin from physical breakdown during the period of 10 min. boil needed to develop color using the cyanoacetamide. Thus, the most appropriate blank is processing separately the solutions of enzyme alone and substrate pectin alone for color development and then adding the two absorbances. Using this improved assay we found that lysophosphatidylethanolamine (LPE) inhibited tomato PG activity. This inhibition appears to depend on the ripening stage of the fruit. Our results suggest that LPE is able to impart firmness to tomato fruit by reducing the PG activity, which in turn could protect the pectin/middle lamellae from enzymic breakdown. The effects of LPE on PG activity are distinct from those of Triton X-100 and lysophosphatidylcholine.
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Roy, Karabi, Sujan Dey, Md Kamal Uddin, Rasel Barua y Md Towhid Hossain. "Extracellular Pectinase from a Novel Bacterium Chryseobacterium indologenes Strain SD and Its Application in Fruit Juice Clarification". Enzyme Research 2018 (21 de marzo de 2018): 1–7. http://dx.doi.org/10.1155/2018/3859752.
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Pectinase is one of the important enzymes of industrial sectors. Presently, most of the pectinases are of plant origin but there are only a few reports on bacterial pectinases. The aim of the present study was to isolate a novel and potential pectinase producing bacterium as well as optimization of its various parameters for maximum enzyme production. A total of forty bacterial isolates were isolated from vegetable dump waste soil using standard plate count methods. Primary screening was done by hydrolysis of pectin. Pectinase activity was determined by measuring the increase in reducing sugar formed by the enzymatic hydrolysis of pectin. Among the bacterial isolates, the isolate K6 exhibited higher pectinase activity in broth medium and was selected for further studies. The selected bacterial isolate K6 was identified as Chryseobacterium indologenes strain SD. The isolate was found to produce maximum pectinase at 37°C with pH 7.5 upon incubation for 72 hours, while cultured in production medium containing citrus pectin and yeast extract as C and N sources, respectively. During enzyme-substrate reaction phase, the enzyme exhibited its best activity at pH of 8.0 and temperature of 40°C using citrus pectin as substrate. The pectinase of the isolate showed potentiality on different types of fruit juice clarification.
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Weis, K. G., V. S. Polito y J. M. Labavitch. "Microfluorometry of pectic materials in the dehiscence zone of almond (Prunus dulcis [Mill.] DA Webb) fruits." Journal of Histochemistry & Cytochemistry 36, n.º 8 (agosto de 1988): 1037–41. http://dx.doi.org/10.1177/36.8.3392393.
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We examined the middle lamella and the primary and secondary walls in almond pericarp dehiscence zone cells using a fluorescent cytochemical method which permitted specific, quantitative detection of pectic cell wall materials. Glycol methacrylate-embedded sections were stained with coriphosphine and pectin-specific fluorescent emissions at 630 nm were quantified using green excitation (546 nm). Examination of sectioned material extracted with purified pecto-lytic enzyme preparations was used to demonstrate the relative specificity of the staining reaction for pectic substances.
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KAMIMIYA, Shuwsei. "Pectin decomposing enzyme in genus Erwinia. Purification and properties of pectin lyase." Journal of the agricultural chemical society of Japan 62, n.º 9 (1988): 1363–65. http://dx.doi.org/10.1271/nogeikagaku1924.62.1363.
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KAPYSHEVA, U., S. BAKHTIYAROVA, B. ZHAKSYMOV, Z. SMAGULOVA y E. TALGATOV. "EFFECT OF PECTIN/MONTMORILLONITE INTESTINAL ADSORBENTS ON BLOOD BIOCHEMICAL PARAMETERS DURING CHRONIC TREATMENT WITH ACETYLSALICYLIC ACID". Periódico Tchê Química 16, n.º 33 (20 de marzo de 2019): 920–26. http://dx.doi.org/10.52571/ptq.v16.n33.2019.935_periodico33_pgs_920_926.pdf.
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Chronic treatment with non-steroidal anti-inflammatory drugs such as acetylsalicylic acid may cause a number of adverse effects and chronic conditions. Intestinal adsorbents based on natural materials are used to prevent or treat various intoxications. In this study, it was described detoxification and protective effect of composite pectin/montmorillonite intestinal adsorbents in rats receiving high doses of acetylsalicylic acid. 60 Wistar rats received 100 mg/kg of acetylsalicylic acid without or together with composite intestinal adsorbents based on montmorillonite and 5%, 10%, and 20% pectin. After 16 days of the experiment, blood samples were collected to measure blood biochemistry profiles, including levels of total protein, albumin, glucose, cholesterol and liver enzymes. It was observed significant changes in blood biochemistry profile as well as in liver enzyme levels in rats receiving acetylsalicylic acid for 16 days. Concomitant administration of acetylsalicylic acid and composite intestinal adsorbents based on montmorillonite and 5%, 10%, and 20% pectin provided a protective effect as judged by recovery of blood biochemistry and liver enzyme profiles to control levels. The composite adsorbent with 20% pectin had maximum effect. Therefore, pectin/montmorillonite intestinal adsorbents can be used to decrease gastrointestinal irritation and adverse effects of drugs, such as acetylsalicylic acid.
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Dartora, Adriana B., Telma E. Bertolin, Denise Bilibio, Mauricio M. Silveira y Jorge A. V. Costa. "Evaluation of Filamentous Fungi and Inducers for the Production of Endo-Polygalacturonase by Solid State Fermentation". Zeitschrift für Naturforschung C 57, n.º 7-8 (1 de agosto de 2002): 666–70. http://dx.doi.org/10.1515/znc-2002-7-820.
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Five strains of filamentous fungi (Aspergillus niger strains NRRL 3122 and T0005007-2, Aspergillus oryzae CCT 3940, Aspergillus awamori NRRL 3112 and a Trichoderma sp.) were compared for their capacity to produce endo-polygalacturonase (endo-PG) in solid state fermentation. Maximum pectinolytic activity was reached in 72 h of growth, the best two fungal strains being A. niger T0005007-2 and A. oryzae CCT 3940. Three types of commercial purified pectin and four of unprocessed pectin (tangerine, orange, Tahiti lime and sweet lime rind) were used to assess the effect of pectin on the production of endo-PG by A. niger T0005007-2. Maximum pectinolytic activity was achieved using 6 and 10% (w/w) of purified pectin as inducer. Depending on the origin of the commercial pectin used as inducer, maximum endo-PG levels varied from 223 to 876 units per gram of dry medium (one endo-PG unit (U) was defined as the quantity of enzyme which caused a reduction in viscosity of 50% in a 1% w/v solution of pectin in 30 min), indicating that care should be taken when choosing this component of the medium. When the crude pectins were used as inducers at the same concentration as purified pectin, maximum endo-PG activities were 250-300 units/g. However, by increasing the amount of Tahiti lime rind to 50% (w/w) maximum endo-PG was 919 U/g, thus opening up the possibility of a low cost medium for endo-PG production.
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Ben-Othman, Sana y Toonika Rinken. "Immobilization of Pectinolytic Enzymes on Nylon 6/6 Carriers". Applied Sciences 11, n.º 10 (18 de mayo de 2021): 4591. http://dx.doi.org/10.3390/app11104591.
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Pectinolytic enzymes are an important tool for sustainable food production, with a wide range of applications in food processing technologies as well as the extraction of bioactive compounds from pectin-rich raw materials. In the present study, we immobilized commercial pectinase preparation onto pellet and thread shaped nylon 6/6 carriers and assessed its stability and reusability. Five commercial pectinase preparations were tested for different pectin de-polymerizing activities (pectinase, polygalacturonase, and pectin lyase activities). Thereafter, Pectinex® Ultra Tropical preparation, exhibiting the highest catalytic activities among the studied preparations (p < 0.0001), was immobilized on nylon 6/6 using dimethyl sulfate and glutaraldehyde. The immobilization yield was in accordance with the carrier surface area available for enzyme attachment, and it was 1.25 ± 0.10 U/g on threads, which was over 40 times higher than that on pellets. However, the inactivation of immobilized enzymes was not dependent on the shape of the carrier, indicating that the attachment of the enzymes on the surface of nylon 6/6 carriers was similar. The half-life of enzyme inactivation fast phase at 4 °C was 12.8 days. After 5 weeks, the unused threads retained 63% of their initial activity. Reusability study showed that after 20 successive cycles the remaining activity of the immobilized pectinase was 22%, indicating the good prospects of reusability of the immobilized enzyme preparations for industrial application.
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Kim, Jongkee y Kenneth C. Gross. "STUDIES ON RHAMNOGALACTURONASE IN FRUIT". HortScience 27, n.º 6 (junio de 1992): 653d—653. http://dx.doi.org/10.21273/hortsci.27.6.653d.
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Rhamnogalacturonase (RGase) is a new fungal enzyme which degrades the highly branched regions of apple fruit cell wall pectin by cleaving the glycosyl linkage between rhamnosyl and galacturonosyl residues (Schols et al., 1990. Carhohydr. Res. 206:105.). This enzyme, if present in fruit, could play a significant role in fruit softening. Partial purification of RGase was accomplished from a fungal enzyme preparation (Pectinex Ultra SP-L, NOVO Ferment) produced from Aspergillus niger. The crude enzyme hydrolyzed chelator-soluble pectin from red ripe tomato fruit. Methylation linkage analysis of the product suggested that an increase in terminal-rhamnosyl residues accompanied pectin hydrolysis, indicative of RGase activity. Cross-linked alginate, hydroxyapatite, and DEAE-Sephadex chromatography were used to partially purify RGase. Polygalacturonase was efficiently removed using the alginate column. Crude pectin obtained from mature-green tomato fruit cell wall by extracting with 0.5 M imidazole buffer (pH 7) and 50 mM Na-carbonate was incubated with pure polygalacturonase and the residue hydrolyzed with 0.1 N trifluoroacetic acid. This modified pectin was used as a substrate to investigate the presence of RGase in tomato and other fruit.
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IZAKI, Kazuo. "Pectin decomposing enzyme in genus Erwinia. Introduction." Journal of the agricultural chemical society of Japan 62, n.º 9 (1988): 1357–59. http://dx.doi.org/10.1271/nogeikagaku1924.62.1357.
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Chakiath, Chacko, Margaret J. Lyons, Robert E. Kozak y Craig S. Laufer. "Thermal Stabilization of Erwinia chrysanthemi Pectin Methylesterase A for Application in a Sugar Beet Pulp Biorefinery". Applied and Environmental Microbiology 75, n.º 23 (9 de octubre de 2009): 7343–49. http://dx.doi.org/10.1128/aem.01010-09.
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ABSTRACT Directed evolution approaches were used to construct a thermally stabilized variant of Erwinia chrysanthemi pectin methylesterase A. The final evolved enzyme has four amino acid substitutions that together confer a Tm value that is approximately 11°C greater than that of the wild-type enzyme, while maintaining near-wild-type kinetic properties. The specific activity, with saturating substrate, of the thermally stabilized enzyme is greater than that of the wild-type enzyme when both are operating at their respective optimal temperatures, 60°C and 50°C. The engineered enzyme may be useful for saccharification of biomass, such as sugar beet pulp, with relatively high pectin content. In particular, the engineered enzyme is able to function in biomass up to temperatures of 65°C without significant loss of activity. Specifically, the thermally stabilized enzyme facilitates the saccharification of sugar beet pulp by the commercial pectinase preparation Pectinex Ultra SPL. Added pectin methylesterase increases the initial rate of sugar production by approximately 50%.
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Rushing, James W. y Donald J. Huber. "Mobility Limitations of Bound Polygalacturonase in Isolated Cell Wall from Tomato Pericarp Tissue". Journal of the American Society for Horticultural Science 115, n.º 1 (enero de 1990): 97–101. http://dx.doi.org/10.21273/jashs.115.1.97.
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Enzymically active cell wall isolated from mature-green and ripening tomato (Lycopersicon esculentum Mill cv. `Rutgers') fruit was employed to investigate the mobility of the enzyme polygalacturonase (PG, EC 3.2.1.15). Cell walls from mature-green `Rutgers' fruit or from the ripening mutant rin, which alone exhibits little or no release of pectin, were unaffected by the addition of enzymically active cell wall from ripening `Rutgers' fruit, indicating that PG is either not transferred at all or is not transferred to sites of pectin hydrolysis. The quantity of pectin released by the addition of soluble PG to enzymically active wall depended on the quantity of enzyme added. Similar data were obtained using purified PG2. Pectin solubilization from all wall isolates exhibiting enzymically mediated pectin release diminished with time; however, transfer to fresh buffer initiated a resumption of autolytic activity, indicating that an inhibitor is released during the course of pectin hydrolysis.
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Hennessey-Ramos, Licelander, Walter Murillo-Arango, Juliana Vasco-Correa y Isabel Cristina Paz Astudillo. "Enzymatic Extraction and Characterization of Pectin from Cocoa Pod Husks (Theobroma cacao L.) Using Celluclast® 1.5 L". Molecules 26, n.º 5 (9 de marzo de 2021): 1473. http://dx.doi.org/10.3390/molecules26051473.
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Cocoa pod husks are a waste generated during the processing of cocoa beans. We aimed to explore the enzymatic extraction of pectin using cellulases. The extraction process was optimized using a central composite design (CCD) and analyzed by response surface methodology (RSM). The parameters optimized were feedstock concentration (%), enzyme dosage (µL/g), and time (h). Three dependent variables were studied: pectin yield (g/100 g dry husk) (R2 = 97.02), galacturonic acid content (g/100 g pectin) (R2 = 96.90), and galacturonic acid yield (g/100 g feedstock) (R2 = 95.35). The optimal parameters were 6.0% feedstock concentration, 40 µL g−1 of enzyme, and 18.54 h, conditions that produced experimentally a pectin yield of 10.20 g/100 g feedstock, 52.06 g galacturonic acid/100 g pectin, and a yield 5.31 g galacturonic acid/100 g feedstock. Using the chemical extraction method, a yield of 8.08 g pectin/100 g feedstock and a galacturonic acid content of 60.97 g/100 g pectin were obtained. Using assisted sonication, a pectin yield of 8.28 g/100 g feedstock and a galacturonic acid content of 42.77 g/100 g pectin were obtained. Enzymatically optimized pectin has rheological and physicochemical features typical of this biomaterial, which provides an interesting alternative for the valorization of cocoa husks.
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Moustacas, A. M., J. Nari, M. Borel, G. Noat y J. Ricard. "Pectin methylesterase, metal ions and plant cell-wall extension. The role of metal ions in plant cell-wall extension". Biochemical Journal 279, n.º 2 (15 de octubre de 1991): 351–54. http://dx.doi.org/10.1042/bj2790351.
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The study of pectin methylesterase and wall-loosening enzyme activities in situ, as well as the estimation of the electrostatic potential of the cell wall, suggest a coherent picture of the role played by metal ions and pH in cell-wall extension. Cell-wall growth brings about a decrease of local proton concentration because the electrostatic potential difference (delta psi) of the wall decreases. This in turn activates pectin methylesterase, which restores the initial delta psi value. This process is amplified by the attraction of metal ions in the polyanionic cell-wall matrix. The amplification process is basically due to the release of enzyme molecules that were initially bound to ‘blocks’ of carboxy groups. This increase of metal-ion concentration also results in the activation of wall-loosening enzymes. Moreover, the apparent ‘inhibition’ of pectin methylesterase by high salt concentrations may be considered as a device which prevents the electrostatic potential from becoming too high.
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TSUYUMU, Shinji. "Pectin decomposing enzyme in genus Erwinia. Role of pectic enzymes in the pathogenicity of soft-rotting Erwinia." Journal of the agricultural chemical society of Japan 62, n.º 9 (1988): 1373–76. http://dx.doi.org/10.1271/nogeikagaku1924.62.1373.
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Ishii, Tadashi, Junji Ichita, Hajime Matsue, Hiroshi Ono y Ikuko Maeda. "Fluorescent labeling of pectic oligosaccharides with 2-aminobenzamide and enzyme assay for pectin". Carbohydrate Research 337, n.º 11 (junio de 2002): 1023–32. http://dx.doi.org/10.1016/s0008-6215(02)00087-3.
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Aguilar, Guillermo, Blanca A. Trejo, Juan M. García y Carlos Huitrón. "Influence of pH on endo- and exo-pectinase production by Aspergillus sp. CH-Y-1043". Canadian Journal of Microbiology 37, n.º 12 (1 de diciembre de 1991): 912–17. http://dx.doi.org/10.1139/m91-158.
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Aspergillus sp. CH-Y-1043 grown on pectins with various degrees of esterification produces endo- and exo-pectinases at pH values as low as 2.5. Maximal production was attained at this pH, although fungal growth only approximated 50% of that obtained at higher pH values. Endopectinase was produced at pH 2.5–3.5 when the fungus was grown on low degree esterified pectin. With higher degree esterified pectin this enzyme was produced at all pH values analyzed. Exopectinase production was less affected by pH values. Still, maximal production was also reached at pH 2.5–3.5. Exopectinase was found to be associated to the cell and could be released after incubation at different pH values, whereas endo pectinase was not detected in the cellular fraction. Results confirmed by SDS–PAGE coupled with in situ activity assays in pectin–agarose gels allowed the identification of a protein band corresponding to endopectinase and a band with pectin esterase activity. Stability of Aspergillus sp. CH-Y-1043 pectinases at various pH values was also evaluated. Key words: Aspergillus sp. CH-Y-1043, extreme acidic pH pectinase production, in situ pectinase detection, cell-associated exopectinase.
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Wang, Lu, Xiaolan Liu, Xiqun Zheng y Yinghua Tian. "Extraction of pectin from flax fiber by chemical means". International Journal of Clothing Science and Technology 27, n.º 3 (1 de junio de 2015): 390–96. http://dx.doi.org/10.1108/ijcst-03-2014-0037.
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Purpose – Building the relationship between retting termination and pectin content remained in the fiber is crucial for ensuring the identity quality of retted flax. In order to measure the pectin content, pectin must be removed thoroughly from the fiber. The purpose of this paper is to find the most suitable method to extract pectin from flax phloem fiber. Design/methodology/approach – Methods of extracting pectin from fruits were employed to ensure the complete removal of pectin from flax for the first time, including extraction with ethylene diamine tetraacetic acid, hydrochloric acid and ion exchange resin. Traditional ammonium oxalate-KOH method was adopted as control. Each procedure was optimized according to the yield of pectin. A characteristic chromogenic technique for determining the exact pectin amount was used, which ensured the precise measurement of pectin extracted. Findings – Results showed that comparing with the traditional ammonium oxalate-KOH method, methods of hydrochloric acid and ion exchange resin extract >95 percent (w/w) pectin and the extract conditions are much milder. Originality/value – Bulk of literatures have covered the problem of how to define the quality of retted flax. But the flax industry in China still uses sensory method to check the retting termination. Connect the fiber quality with pectin content is a brand new idea. Also, the exaction method employed from fruit pectin extract is applied in flax pectin for the first time. These methods are essential for building the relationship between the pectin content and retting termination and also significant for discovering the suitable enzyme for enzyme retting.
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Morais, Patrícia Lígia Dantas de, Luiz Carlos de Oliveira Lima, Maria Raquel Alcântara de Miranda, José Donizete Alves, Ricardo Elesbão Alves y José Daniel Silva. "Enzyme activities and pectin breakdown of sapodilla submitted to 1-methylcyclopropene". Pesquisa Agropecuária Brasileira 43, n.º 1 (enero de 2008): 15–20. http://dx.doi.org/10.1590/s0100-204x2008000100003.
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The objective of this work was to investigate the influence of 1-methylcyclopropene (1-MCP) at 300 nL L-1 on activities of cell wall hidrolytic enzymes and pectin breakdown changes which Sapodilla (Manilkara zapota cv. Itapirema 31) cell wall undergoes during ripening. Sapodilla were treated with ethylene antagonist 1-MCP at 300 nL L-1 for 12 hours and then, stored under a modified atmosphere at 25º C for 23 days. Firmness, total and soluble pectin and cell wall enzymes were monitored during storage. 1-MCP at 300 nL L-1 for 12 hours delayed significantly softening of sapodilla for 11 days at 25º C. 1-MCP postharvest treatment affected the activities of cell wall degrading enzymes pectinmethylesterase and polygalacturonase and completely suppressed increases in beta-galactosidase for 8 days, resulting in less pectin solubilization. Beta-galactosidase seems relevant to softening of sapodilla and is probably responsible for modification of both pectin and xyloglucan-cellulose microfibril network.
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Ogbonnaya, Nwokoro y Eze Chukwuemeka. "Production of polygalacturonase by Aspergillus niger BC23 isolated from Irvingia gabonensis (African mango) fruit". Chemical Industry 70, n.º 6 (2016): 717–24. http://dx.doi.org/10.2298/hemind150327007o.
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Polygalacturonase was produced from Aspergillus niger BC 23 which was isolated from spoiled Irvingia gabonensis fruit. The influence of carbon substrates on enzyme production showed that the medium containing sucrose produced a maximum enzyme yield of 38.5 U/mg protein after 72 h. Enzyme productivity in this medium was much higher than in the medium that contained only citrus pectin as the sole carbon source. Medium containing yeast extract as a nitrogen source caused the production of specific enzyme activity of 31.2 U/mg protein. Results on the effect of metal ions on enzyme activity showed that Ca2+ gave a percent relative activity of 214% in comparison to the native enzyme activity. The enzyme showed maximum activity in slight acid and neutral pH media with optimal activity at pH 4.0. Temperature activity profile of the enzyme showed best activity at a temperature of 35?C. Dried fruit peels were tested for their abilities to support enzyme production in a media devoid of citrus pectin. The best enzyme productivity of 102.3 U/mg protein was achieved after 72 h in the medium containing orange peel and this level was much higher than that achieved when pure carbon sources or citrus pectin alone were used for enzyme production.