Academic literature on the topic 'Pectinase enzyme'
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Journal articles on the topic "Pectinase enzyme"
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Roy, Karabi, Sujan Dey, Md Kamal Uddin, Rasel Barua, and Md Towhid Hossain. "Extracellular Pectinase from a Novel Bacterium Chryseobacterium indologenes Strain SD and Its Application in Fruit Juice Clarification." Enzyme Research 2018 (March 21, 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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-, Shilpa, Mandheer Kaur, and Yogita Jadon. "Isolation and Screening of Pectinase Producing Bacteria from Soil Sample." CGC International Journal of Contemporary Technology and Research 3, no. 2 (July 17, 2021): 166–70. http://dx.doi.org/10.46860/cgcijctr.2021.06.31.166.
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The vast majority of the industrial use of enzymes is covered from microorganisms. Microorganisms are favoured in industry because of their several advantages for example rapid growth, short life expectancy and simplicity in doing genetic alterations. Microbial enzymes are thus amply provided, very much standardized and promoted by many companies. Among various enzymes, Pectinases hold an exceptional place because of its different uses in various sectors like food, textile and biofuel industries.A total of 25% of total enzyme market is being shared by Pectinase alone.The current study was carried out to evaluate the pectinase activity of the pectinolytic bacteria. 40 Bacterial strains were isolated from different soil samples and screened for Pectinase production. Primary and Secondary screening showed 3 potential isolates I38 , I39 and I40 showing pectin degradation on Vincent’s media. Further, extracellular pectinase was partially purified by ammonium sulphate precipitation and dialysis. Sequential ammonium sulphate saturations from 20-80% i.e. (20, 40, 60 and 80%) showed 60% ammonium sulphate was optimum for precipitation of intracellular enzyme whereas 80% was optimum for extracellular enzyme.
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Berutu, Cocok Ana Maryani, Fahrurrozi Fahrurrozi, and Anja Meryandini. "Pectinase Production and Clarification Treatments of Apple (Malus Domestica) Juice." ANNALES BOGORIENSES 21, no. 2 (February 28, 2018): 63. http://dx.doi.org/10.14203/ab.v21i2.311.
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Pectinases are a group of an enzyme that break down pectin, a polysaccharide that is found in plant cell walls. Today, the application of pectinolytic enzymes plays an important role in food technology for the maceration of fruits and vegetables, including for the extraction and clarification of juice. This research aimed to produce pectinase enzyme for clarifying of apple juice. A microbial culture was selected from cocoa bean fermentation samples and identified as Bacillus sp.. The highest enzyme activity was investigated after 48 hours of incubation. Citrus pectin as the carbon source and peptone as the nitrogen source was found as the best component for pectinase production. The optimum condition of pectinase activity was observed at pH 5, temperature 40 °C and the crude enzyme had the higher activity at one hour storage. Apple juice was treated with the enzyme at different concentrations (0%, 0.5%, 1%, 2%, 4%). Apple juice clarification was evaluated for its percent clarity and viscosity. The result showed that enzyme treatment at 4% in apple juice promoted juice clarification and decreased pH and viscosity. In conclusion, the quality of apple juice can be improved by enzymatic treatment using pectinase.
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Berutu, Cocok Ana Maryani, Fahrurrozi Fahrurrozi, and Anja Meryandini. "Pectinase Production and Clarification Treatments of Apple (Malus Domestica) Juice." ANNALES BOGORIENSES 21, no. 2 (December 22, 2017): 63. http://dx.doi.org/10.14203/ann.bogor.2017.v21.n2.63-68.
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Pectinases are a group of an enzyme that break down pectin, a polysaccharide that is found in plant cell walls. Today, the application of pectinolytic enzymes plays an important role in food technology for the maceration of fruits and vegetables, including for the extraction and clarification of juice. This research aimed to produce pectinase enzyme for clarifying of apple juice. A microbial culture was selected from cocoa bean fermentation samples and identified as Bacillus sp.. The highest enzyme activity was investigated after 48 hours of incubation. Citrus pectin as the carbon source and peptone as the nitrogen source was found as the best component for pectinase production. The optimum condition of pectinase activity was observed at pH 5, temperature 40 °C and the crude enzyme had the higher activity at one hour storage. Apple juice was treated with the enzyme at different concentrations (0%, 0.5%, 1%, 2%, 4%). Apple juice clarification was evaluated for its percent clarity and viscosity. The result showed that enzyme treatment at 4% in apple juice promoted juice clarification and decreased pH and viscosity. In conclusion, the quality of apple juice can be improved by enzymatic treatment using pectinase.
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Amanat, Fatima, Amna Yaqoob, Asif Ali, and Muhammad Sajjad. "Extracellular Production of Pectinase from Bacteria Isolated from Rotten Apples from Lahore, Pakistan." BioScientific Review 01, no. 03 (September 2019): 37–45. http://dx.doi.org/10.32350/bsr.0103.05.
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Pectins are intricate blends of polysaccharides which make up around 33% of plantcell wall. Despite of their presence in the greater part of plant body and in other sources, commercial production of pectin is extremely difficult. This is a systematic study that aimed to produce pectinase from bacterial species isolated from rotten apple samples. Zymography and enzyme assay through DNS method were performed to check the pectinolytic activity of bacteria isolated from rotten apple samples. Of all five bacterial species (Serratia marcescens, Klebseilla pneumoniea, Pseudomonas aeruginosa and Escherichia coli) maximum enzyme concentration was showed in Pseudomonas aeruginosa and it was 6.2 U/mL. The major achievement of this study was to screen out the most efficient pectinases producing isolate of Serratia marcescens from rotten apples that has never been reported to produce pectinase, previously.
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Mohan, Nayana, and Archana Prabhat. "Isolation, Production and Application of Bacterial Pectinase for Industrial Use." Indian Journal of Nutrition and Dietetics 55, no. 4 (October 9, 2018): 442. http://dx.doi.org/10.21048/ijnd.2018.55.4.22116.
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Production of microbial enzymes at the industrial scale and their commercialization has gained a lot of focus and importance. Some of the industrially important enzymes from microbial origin include lipases, amylases, proteases, xylynases, pectinases etc. The objective of the study was production and application of bacterial pectinase for industrial use (clarification of fruit juices). Here the isolation of microorganism and characterization was done, then pectinase assay was performed and finally fruit juice was clarified using this enzyme. Here decayed orange peel was used as the sample and it was collected from a local market, South Kalamsseri- Cochin. The collected decayed orange part was subjected to serial dilution in order to isolate the organism. The dilutions were then plated on appropriate media (pecin agar media) and spread plate was performed. After the incubation time, colonies with zone were obtained which showed the production of pectinase enzyme. These isolated colonies were then inoculated to the petri plate containing pectin agar media and streak plate was performed. After 24 h incubation, the isolated colonies were subjected to Gram’s staining. It was Gram negative bacilli. The biochemical characterization (IMViC test) was done and VP Citrate tests were positive. Then the colonies were inoculated in Pectinase Production Broth. After 24 h incubation, the media was centrifuged for the isolation of enzymes. The enzyme assay was done by titration technique and the enzyme activity was found to be 0.78 U. This isolated enzyme was used for the clarification of apple juice and lime juice. According to the findings obtained from the study, the clarification of fruit juice by the use of bacterial pectinase is most cost effective and yield good results for industrial use.
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Alqahtani, Yahya S., Sunil S. More, Keerthana R., Ibrahim Ahmed Shaikh, Anusha K. J., Veena S. More, Francois N. Niyonzima, Uday M. Muddapur, and Aejaz A. Khan. "Production and Purification of Pectinase from Bacillus subtilis 15A-B92 and Its Biotechnological Applications." Molecules 27, no. 13 (June 29, 2022): 4195. http://dx.doi.org/10.3390/molecules27134195.
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Enzymes that degrade pectin are called pectinases. Pectinases of microbial origin are used in juice clarification as the process is cost-effective. This study screened a pectinase-producing bacterium isolated from soil and identified as Bacillus subtilis 15A B-92 based on the 16S rRNA molecular technique. The purified pectinase from the isolate showed 99.6 U/mg specific activity and 11.6-fold purity. The molecular weight of the purified bacterial pectinase was 14.41 ± 1 kD. Optimum pectinase activity was found at pH 4.5 and 50 °C, and the enzyme was 100% stable for 3.5 h in these conditions. No enzymatic inhibition or activation effect was seen with Fe2+, Ca2+, or Mg2+. However, a slight inhibition was seen with Cu2+, Mn2+, and Zn2+. Tween 20 and 80 slightly inhibited the pectinase, whereas iodoacetic acid (IAA), ethylenediaminetetraacetate (EDTA), urea, and sodium dodecyl sulfate (SDS) showed potent inhibition. The bacterial pectinase degraded citrus pectin (100%); however, it was inactive in the presence of galactose. With citrus pectin as the substrate, the Km and Vmax were calculated as 1.72 mg/mL and 1609 U/g, respectively. The high affinity of pectinase for its substrate makes the process cost-effective when utilized in food industries. The obtained pectinase was able to clarify orange and apple juices, justifying its application in the food industry.
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Aguilar, Guillermo, Blanca A. Trejo, Juan M. García, and Carlos Huitrón. "Influence of pH on endo- and exo-pectinase production by Aspergillus sp. CH-Y-1043." Canadian Journal of Microbiology 37, no. 12 (December 1, 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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KC, Sudeep, Jitendra Upadhyaya, Dev Raj Joshi, Binod Lekhak, Dhiraj Kumar Chaudhary, Bhoj Raj Pant, Tirtha Raj Bajgai, et al. "Production, Characterization, and Industrial Application of Pectinase Enzyme Isolated from Fungal Strains." Fermentation 6, no. 2 (June 9, 2020): 59. http://dx.doi.org/10.3390/fermentation6020059.
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Pectinases are the group of enzymes that catalyze the degradation of pectic substances. It has wide applications in food industries for the production and clarification of wines and juices. The aim of this study was to isolate, screen and characterize pectinase from fungi isolated from various soil samples and evaluate its application in juice clarification. Fungal strains were isolated and screened primarily using 1% citruspectin incorporated potato dextrose agar (PDA) and secondarily using pectinase screening agar medium (PSAM) for pectinolytic organisms. The enzyme was produced by submerged state fermentation and assayed using the dinitro salicylic acid (DNS) method. From 20 different soil samples, 55 fungal isolates were screened primarily and, among them, only 14 isolates were subjected for secondary screening. Out of 14, only four strains showed the highest pectinolytic activity. Among four strains, Aspergillus spp. Gm showed the highest enzyme production at a 48-h incubation period, 1% substrate concentration, and 30 °C temperature. The thermal stability assessment resulted that the activity of pectinase enzyme declines by 50% within 10 min of heating at 60 °C. The optimum temperature, pH, and substrate concentration for the activity of enzyme was 30 °C (75.4 U/mL), 5.8 (72.3 U/mL), and 0.5% (112.0 U/mL), respectively. Furthermore, the yield of the orange juice, the total soluble solid (TSS), and clarity (% transmittance) was increased as the concentration of the pectinase increased, indicating its potential use in juice processing. Overall, the strain Aspergillus spp. Gm was identified as a potent strain for pectinase production in commercial scale.
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CHAMANI, Esmaeil, Seyyed Karim TAHAMI, Nasser ZARE, Rasool Asghari-ZAKARIA, Mehdi MOHEBODINI, and Daryl JOYCE. "Effect of Different Cellulase and Pectinase Enzyme Treatments on Protoplast Isolation and Viability in Lilium ledebeourii Bioss." Notulae Botanicae Horti Agrobotanici Cluj-Napoca 40, no. 2 (November 5, 2012): 123. http://dx.doi.org/10.15835/nbha4028055.
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For overcoming interspecific incompatibility, protoplast combination method is a proper procedure for making a new plant withdesired traits. For this purpose, protoplast preparation is a first and important step. Hence, experiments were conducted to evaluatevarious combinations of cellulose, pectinase and their treatment times on protoplast production and protoplast viability in Liliumledebeourii Bioss. The results of experiment revealed that the protoplast yield was significantly affected by different treatment levels.Cellulase at 4% gave the highest numbers of protoplasts at 3.71×105 protoplast/g FW. Pectinase at 1% gave the highest numbers ofprotoplast. For treatment times, the highest yield of protoplast was with leaf explants treated for 24 h. Analysis of variance indicated thatconcentration, time and three-way interaction of cellulase, pectinase and time were significant at p<0.01. Cellulase at 4% and pectinase at0.2% for 24 h gave the highest viability. Interactions of cellulase × pectinase, cellulase × time, pectinase × time and cellulase × pectinase× treatment time were significant at P≤0.05 for protoplast number. The highest and lowest protoplast numbers were produced in mediacontaining 4% cellulase and 1% pectinase for 24 h (6.65×105 protoplast/g FW) and 1% cellulase and 0.2% pectinase for 12 h, respectively.It’s concluded that, the best treatment for isolation of Lilium protoplast was 4% cellulase and 1% pectinase for 24 h.
Dissertations / Theses on the topic "Pectinase enzyme"
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Göğüş, Nihan Tarı Canan. "Effect of The Morphology of Aspergillus Sojae on Pectinase Enzyme and The Optimization of Fermentation Conditions/." [s.l.]: [s.n.], 2006. http://library.iyte.edu.tr/tezlerengelli/master/gidamuh/T000578.pdf.
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Dalagnol, Luíza Merlini Garcia. "Avaliação do uso do ultrassom na extração do mosto da uva cabernet sauvignon e na atividade enzimática." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/158743.
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O processamento da uva para produção de suco e vinho engloba diferentes processos tecnológicos, como por exemplo, o tratamento enzimático, onde usualmente são utilizadas preparações de enzimas comerciais, buscando-se aprimorar processos como clarificação e extração. Entretanto, esse é um tratamento que demanda elevado tempo de processamento, sendo relevante a busca por novas tecnologias a fim de apurar o processo. O ultrassom pode ser utilizado como uma alternativa para reduzir o tempo de processamento e acrescer qualidade ao produto, pois além de ser uma técnica sustentável, pode proporcionar benefícios no uso combinado com enzimas, favorecendo as reações em decorrência de seus efeitos. Neste trabalho, o uso em conjunto de tratamento enzimático (ET), ultrassom (US), e agitação mecânica (MS) foi avaliado na extração do mosto da uva Cabernet Sauvignon, a fim de compreender os efeitos das técnicas combinadas. Inicialmente, nove preparados enzimáticos comerciais foram caracterizados segundo suas atividades enzimáticas e aplicados para extração do mosto, avaliando a variação de temperatura (40, 50 e 60 °C), tempo (15 e 30 min), e concentração de enzima (0,01 a 2,0 U.g-1). Os melhores resultados foram obtidos com o preparado Zimopec PX5® nas condições de 1,0 U.g-1 de pectinase a 50 °C por 30 min. A extração do mosto apresentou aumento significativo nos parâmetros de qualidade avaliados (cor, sólidos solúveis totais, rendimento de extração, capacidade antioxidante, antocianinas totais) quando os três métodos de extração (US, MS e ET) foram combinados, principalmente na presença do ultrassom. Tendo em vista o efeito sinérgico obtido entre a aplicação enzimática e o ultrassom na extração do mosto, um novo estudo foi conduzido buscando investigar a influência da sonicação na eficiência catalítica das enzimas pectinase (PE), xilanase (XLN) e celulase (CE). Para isso, as atividades enzimáticas foram avaliadas em diferentes pHs e em amostras de enzima e substratos submetidas a um tratamento prévio de sonicação por tempos determinados (0 – 30 min). Os parâmetros cinéticos e termodinâmicos foram estimados, apresentando um efeito positivo do US na atividade das enzimas. A sonicação prévia do substrato contribuiu significativamente para o aumento da atividade de XLN, enquanto a sonicação prévia da enzima melhorou a atividade da CE e PE. Os resultados apresentaram um aumento na velocidade de hidrólise das enzimas com o uso do US, assim como um aumento da eficiência catalítica (Vmax/Km), mostrando o potencial da aplicação do US para ativação das enzimas. De acordo com os resultados obtidos, pode-se afirmar que o ultrassom proporcionou melhorias na extração do mosto, podendo ser utilizado como uma técnica alternativa de processo, bem como apresentou efeitos benéficos sobre as atividades enzimáticas.Grape processing for juice and wine production encompasses different technological processes, such as enzymatic treatment, that usually uses commercial enzyme preparations to improve clarification and extraction processes. However, this is a treatment that demands high processing time, being relevant the search for new technologies in order to improve the whole process. Ultrasound (US) can be used as an alternative to reduce the processing time and improve the quality of the product, moreover, it can provide benefits in the combined use with enzymes, favoring the enzymatic reactions. In this work, the combined use of enzymatic treatment (ET), ultrasound (US), and mechanical agitation (MS) was studied in order to understand the effects of the techniques on Cabernet Sauvignon must extraction. Initially, nine commercial enzyme preparations were characterized according to their enzymatic activities and applied to must extraction, evaluating temperature (40, 50 and 60 °C), time (15 and 30 min), and enzyme concentration (0.01 to 2.0 Ug-1). The best results were obtained for the preparation Zimopec PX5® under conditions of 1.0 U.g-1 of pectinase at 50 °C for 30 min. A significant increase on quality parameters (color, °Brix, yield, antioxidant capacity, total anthocyanins) was obtained to extraction combining the three methods (US, MS and ET), mainly when US were applied. Based on these previous results, a new study was conducted to investigate the influence of sonication on the catalytic efficiency of the enzymes pectinase (PE), xylanase (XLN) and cellulase (CE). The enzymatic activities were evaluated at different pH and in samples of enzyme and substrates submitted to a previous treatment of sonication by determined times (0 - 30 min). The kinetic and thermodynamic parameters were estimated, showing a positive effect of the ultrasonic treatment on the enzymatic activity. Previous sonication of the substrate contributed significantly to the increase in XLN activity, whereas the previous sonication of the enzyme improved the activity of CE and PE. This research showed the potential benefits of ultrasound treatment on reaction rate and catalytic efficiency (Vmax/Km) improvement of enzymes, attesting that US can be used to increase the catalytic efficiency of pectinase, xylanase and cellulase enzymes. According to the obtained results, it can be affirmed that ultrasound improved the extraction process, and can be applied as an alternative technique, as well as provided beneficial effects on the enzymatic activity.
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Gacura, Matthew David. "Drivers of Fungal Community Composition and Function In Temperate Forests." Kent State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=kent1543579763552776.
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Byarugaba-Bazirake, George William. "The effect of enzymatic processing on banana juice and wine." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/1633.
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Pedrolli, Danielle Biscaro [UNESP]. "Caracterização físico-química de pectinases extracelulares purificadas de Aspergillus giganteus." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/95014.
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pedrolli_db_me_rcla.pdf: 676301 bytes, checksum: a4723de4ae9b6c5b9f1e2619ab7118b5 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O fungo Aspergillus giganteus produz uma única poligalacturonase (PG) quando cultivado em meio líquido com pectina de citrus como única fonte de carbono, e pelo menos três pectina liases (PL) quando cultivado em meio líquido com resíduo de laranja como fonte de carbono. A PG de A. giganteus foi purificada em duas etapas: precipitação de proteínas com 70% de saturação com sulfato de amônio e troca aniônica. A PG purificada apresentou massa molar de 69,7±0,07 kDa. A máxima atividade da enzima foi observada em pH 6,0 a 55-60ºC, sendo essa estável em meio neutro e alcalino. A PG apresentou meias-vidas de 115, 18 e 6 min quando incubada a 40, 50 e 55 ºC, respectivamente. A enzima mostrou-se ativa sobre substratos de qualquer grau de metilação, com maior especificidade para substratos de baixa ou nenhuma metilação, apresentando Vmax 669,6 e 602,8 μmol/mg.min, Km 3,25 e 1,16 mg/mL, kcat 770 e 690 s-1 sobre pectina de citrus 34 % esterificada e ácido poligalacturônico, respectivamente. A PG apresentou atividade exo liberando apenas ácido galacturônico como produto de hidrólise. 2-Mercaptoetanol, DTT, Co2+, Mn2+, Mg2+, NH4 + e Na+ agiram como estimulantes da atividade PG. Já Hg2+, EDTA, citrato de sódio, ácido iodoacético, SDS, Ba2+, Cu2+, Pb2+ e Zn2+ inibiram essa atividade enzimática. A principal pectina liase de A. giganteus, a PL I, foi purificada em três etapas: troca aniônica, troca catiônica e filtração em gel. A massa molar da PL I foi estimada em 55,7±1,4 kDa. A máxima atividade da enzima foi obtida em pH 8,5 a 50ºC. A PL I apresentou meias-vidas de 19, 9 e 6 min a 40, 45 e 50ºC, respectivamente. As maiores atividades da PL I foram observadas em pectinas de citrus com 34 e 72% de metilação, nas quais apresentou Vmax 1.488,1 e 1.129,8 U/mg.min, respectivamente, e Km 4,8 mg/mL para ambos os substratos. O padrão de degradação da pectina...
Aspergillus giganteus produces one polygalacturonase (PG) on liquid medium with citrus pectin as the only carbon source, and at least three pectin lyases (PL) with orange waste. Homogenous PG was obtained after two steps: protein precipitation with 70 % ammonium sulphate saturation and anionexchange chromatography. The purified PG showed molecular weight of 69.7±0,07 kDa. The enzyme exhibited maximal activity at pH 6.0 and 55-60 °C, and was stable in neutral and alkaline medium. The half-live for PG at 40, 50 and 55 °C was 115, 18 and 6 min, respectively. The enzyme was active on substrates with any methyl-esterification degree, and hydrolysed better low esterified and not esterified substrates, showing Vmax 669.6 and 602.8 μmol. mg-1.min-1, Km 3.25 and 1.16 mg/mL, kcat 770 and 690 s-1 on 34 % esterified citrus pectin and polygalacturonic acid, respectively. The unique soluble product released in the reaction with pectin and polygalacturonic acid was monogalacturonic acid, and according to this results the enzyme can be classified as exoPG. PG activity enhanced in presence of 2-mercaptoethanol, DTT, Co2+, Mn2+, Mg2+, NH4 + and Na+, and was completely inhibited in presence of Hg2+. EDTA, sodium citrate, iodoacetic acid, SDS, Ba2+, Cu2+, Pb2+ and Zn2+ inhibited enzyme activity. The main PL from A. giganteus was called PL I and was purified after three steps: anion-exchange and cation-exchange chromatographies, and gel filtration. The purified PL I showed molecular weight of 55.7±1.4 kDa. The enzyme exhibited maximal activity at pH 8.5 and 50 °C, and was stable in neutral and acid medium. The half-live for PL I at 40, 45 and 50 °C was 19, 9 and 6 min, respectively. The enzyme was more active on citrus pectins with 34 and 72% of esterification, showing Vmax 1,488.1 and 1,129.8 U. mg-1.min-1, repectively, and Km 4.8 mg/mL on both substrates. The degradation pathern on 34% esterified...(Complete abstract click electronic access below)
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Hassan, Sozan. "Caractérisation de nouvelles enzymes impliquées dans la dégradation de polysaccharides végétaux à partir de la bactérie Dickeya dadantii 3937." Thesis, Lyon, INSA, 2011. http://www.theses.fr/2011ISAL0115.
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La bactérie phytopathogène Dickeya dadantii est responsable de la pourriture molle de nombreux végétaux. Elle sécrète dans le milieu extérieur toute une batterie d’enzymes capables de dégrader les constituants des parois végétales. La première partie de mon travail concerne les féruloyl estérases FaeD et FaeT. Les féruloyl estérases sont responsables de l’hydrolyse de liaisons ester entre l’acide férulique et les chaînes de xylane ou de pectine. En clivant ces liaisons, elles favorisent une dégradation complète de la paroi végétale. L'importance de ces enzymes nous a conduit à rechercher si D. dadantii produit de telles estérases. Le criblage d’une banque de gènes par un test de détection de l’activité féruloyl estérase a permis d’identifier deux gènes qui ont été caractérisés. Alors que faeT est faiblement transcrit dans toutes les conditions, la transcription de faeD est fortement induite en présence d’acide férulique et contrôlée par le régulateur FaeR. Alors que FaeT est une protéine cytoplasmique, FaeD est sécrétée par le système Out qui permet la sécrétion de nombreuses pectinases. Les enzymes FaeD et FaeT ont été surproduites dans E. coli et leurs principales propriétés biochimiques ont été déterminées. La connaissance de la séquence complète du génome de D. dadantii permet d’aborder des études de génomique fonctionnelle. Cette séquence confirme la présence des gènes codant les pectinases déjà caractérisées et révèle que ce génome code de nouvelles pectinases potentielles. La deuxième partie de mon travail concerne le gène pelN identifié par analyse du génome. Les pectate lyases coupent les liaisons glycosidiques du polygalacturonate par une réaction de β-élimination, générant des produits insaturés. Leur mécanisme d’action nécessite des cations comme cofacteur, en général Ca2+. Après clonage du gène pelN, la protéine PelN a été surproduite dans E. coli. Son activité pectate lyase a été prouvée en montrant sa capacité à produire des dérivés insaturés à partir de polygalacturonate ou de pectines plus ou moins méthylées. Cette étude démontre que PelN est la première pectate lyase utilisant les ions Fe2+ comme cofacteur préférentiel. Chez D. dadantii, l’expression du gène pelN dépend de divers régulateurs affectant la synthèse des pectinases, comme PecS ou GacA. PelN est une protéine extracellulaire sécrétée par le système Out. Ces études contribuent à mieux comprendre le rôle respectif des différentes enzymes impliquées dans la dégradation de la paroi végétale et le fonctionnement coopératif de ce système pluri-enzymatiqueThe phytopathogenic bacterium Dickeya dadantii is responsible for soft rot diseases of various plants. It secretes in the external medium a large array of enzymes which are able to degrade the constituents of the plant-cell wall. The first part of my work was related to the féruloyl esterases FaeD and FaeT. Feruloyl esterases are responsible for the hydrolysis of ester linkages between ferulic acid and the xylan or pectin chains. By cleaving these linkages, they improve the complete degradation of the plant-cell wall. The importance of these enzymes led us to search whether D. dadantii produces such esterases. A gene bank screening using a specific detection test for the feruloyl esterase activity allowed us to identify two genes which were characterized. While faeT is weakly transcribed in all the conditions, the faeD transcription is strongly induced in the presence of ferulic acid and it is controlled by the regulator FaeR. Whereas FaeT is a cytoplasmic protein, FaeD is secreted by the Out system responsible for the secretion of several pectinases. The enzymes FaeD and FaeT were overproduced in E. coli and their main biochemical properties were determined. The determination of the complete sequence of the D. dadantii genome makes it possible to develop functional genomic studies. This sequence confirms the presence of genes encoding the previously characterized pectinases and it reveals that this genome encodes new potential pectinases. The second part of my work was related to the gene pelN identified by genome analysis. Pectate lyases cleave the glycosidic bounds in the polygalacturonate chain by a β-elimination reaction, generating unsaturated products. This reaction mechanism requires cations as cofactor, generally Ca2+. After cloning of the gene pelN, the protein PelN was overproduced in E. coli. Its pectate lyase activity was demonstrated by its capacity to produce unsaturated derivatives from polygalacturonate or pectins. This study showed that PelN is the first pectate lyase that uses Fe2+ ions as the preferential cofactor. In D. dadantii, the pelN expression depends on various regulators controlling the pectinase synthesis, such as PecS or GacA. PelN is an extracellular protein secreted by the Out system. These studies contribute to increase the knowledge on the respective role of the different enzymes involved in the degradation of the plant-cell wall and the cooperative interactions in this pluri-enzymatic system
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Zhang, Jing. "Biochemical Study and Technical Applications of Fungal Pectinase." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6295.
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Altan, Asena Yenidünya Ali Fazıl. "Isolation And Molecular Characterization of Extracellular Lipase And Pectinase Producing Bacteria From Olive Oil Mills/." [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/biyoteknoloji/T000497.pdf.
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Sykes, Melissa. "Do zoospores of Phytophthora cinnamomi produce enzymes such as cutinases, cellulases and pectinases?" Thesis, Sykes, Melissa (1995) Do zoospores of Phytophthora cinnamomi produce enzymes such as cutinases, cellulases and pectinases? Honours thesis, Murdoch University, 1995. https://researchrepository.murdoch.edu.au/id/eprint/32817/.
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Sandri, Ivana Greice. "Enzimas pectinolíticas : seleção de linhagens fúngicas produtoras, caracterização e aplicação em processos da indústria de alimentos." reponame:Repositório Institucional da UCS, 2010. https://repositorio.ucs.br/handle/11338/516.
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Nesse trabalho, isolados fúngicos obtidos de vegetais em decomposição foram testados quanto à sua capacidade de produzir pectinases aplicáveis ao tratamento enzimático de sucos de maçã e de mirtilo. Com base na secreção de endo-poligalacturonase (endo-PG), dois isolados identificados e denominados Aspergillus niger LB23 e Aspergillus fumigatus LB39J foram selecionados para uso em processos em estado sólido e submerso, respectivamente. Os extratos enzimáticos dessas linhagens não apresentam teores de aflatoxinas totais (B1, B2, G1, G2) até um limite de detecção de 2 μg/Kg. A preparação enzimática obtida em cultivo em estado sólido de A. niger LB23 apresentou maiores atividades de endo-PG e exo-poligalacturonase (exo-PG) em pH 4,0, enquanto a reação enzimática com os extratos enzimáticos obtidos em cultivos submersos de A. fumigatus LB39J foram favorecidos em pH entre 4,0 e 5,0, para endo-PG, e 5,0, para exo-PG. Com relação à temperatura de reação da preparação pectinolítica de A. niger LB23, endo e exo-PG mostraram melhores desempenhos nas faixas 40-50°C e 50-60°C, respectivamente. Para as poligalacturonases de A. fumigatus LB39J, definiu-se um intervalo entre 40 e 60°C, para endo-PG, e 60ºC, para exo-PG, como as melhores temperaturas. Quando a estabilidade térmica das poligalacturonases presentes em ambas as preparações foi avaliada, observou-se preservação de cerca de 70% das atividades após 150 minutos de exposição a temperaturas de até 40ºC. Foi avaliada a influência de diferentes concentrações de glicose e pectina sobre os resultados do processo em cultivos em estado sólido com A. niger LB23, sendo observado incremento das atividades de endo e exo-PG em meio com 6% (m/m) de pectina e isento de glicose, atingindo-se 65 unidades por grama de meio seco (U/g) e 198 U/g, respectivamente. Em cultivos submersos com A. fumigatus LB39J, maiores atividades foram obtidas em meio com 20 g/L de pectina e sem glicose: 42 U/mL de endo-PG e 32 U/mL de exo-PG. Nas condições definidas para o processo submerso, foram testados diferentes valores de pH inicial do meio. As máximas atividades foram observadas com pH inicial 3,0 para endo-PG (44 U/mL) e 4,0 para exo-PG (37 U/mL). Adicionalmente, em fermentador de bancada, constatou-se que um valor de pH inicial de 4,0, com o valor mínimo sem controle e, após, com o valor máximo controlado em 3,5, proporcionou as maiores atividades com 81 U/mL de endo-PG e 49 U/mL de exo-PG. Comparando-se os extratos enzimáticos produzidos pelas linhagens selecionadas, verificou-se que as pectinases produzidas por A. niger LB23 foram mais eficientes na hidrólise enzimática das substâncias pécticas presentes nos sucos de maçã e mirtilo, proporcionando, maior redução de turbidez (90 e 40%) e viscosidade (40 e 60%) e aumento na clarificação (90 e 55%). Esses resultados indicam o potencial das pectinases de A. niger LB23 para o tratamento enzimático de sucos de frutas, ressaltando-se que o teor de compostos fenólicos e a capacidade antioxidante dos sucos foram, em sua maior parte, preservados após o tratamento.Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-06-02T17:45:32Z No. of bitstreams: 1 Tese Ivana Greice Sandri.pdf: 1824755 bytes, checksum: c0fad543a60bbb77cd7beb3d28893487 (MD5)
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In this work, fungus samples isolated from decomposing vegetables were tested with respect to their capacity of producing pectinases to be applied to the enzymatic treatment of apple and bilberry juices. Taking in account the secretion of endo-polygalacturonase (endo-PG), two isolates which were identified and named Aspergillus niger LB23 e Aspergillus fumigatus LB39J were selected for solid-state and submerged cultivations, respectively. The enzymatic extracts from these strains did not present total aflatoxin (B1, B2, G1, G2) levels up to detection limit of 2 μg/Kg. The enzyme preparation obtained from solid-state cultivation of A. niger LB23 showed the largest activities of both endo-PG and exo-polygalacturonase (exo-PG) at pH 4.0, whereas the reaction with submerged A. fumigatus L39J enzymatic extracts was favoured at pH between 4.0 and 5.0 for endo-PG and 5.0 for exo-PG. With respect to the reaction temperature for A. niger LB23 pectinolytic preparation, endo and exo-PG showed the best performances at the ranges 40-50ºC and 50-60ºC, respectively. For A. fumigatus L39J polygalacturonases, a range from 40 to 60ºC, for endo-PG, and 60ºC, for exo-PG, were defined as the best temperatures. When the thermal stability of polygalacturonases present in both preparations was evaluated, preservation of about 70% of activities was observed after exposing the enzymes to temperatures up to 40ºC for 150 minutes. The influence of different glucose and pectin concentrations on the results of the solid-state process with A. niger LB23 was assessed and an increment in endo and exo-PG activities were observed in medium containing 6% (w/w) of pectin and absence of glucose, with activities of 65 units per gram of dry medium (U/gdm) and 198 U/gdm being achieved. In submerged cultivation of A. fumigatus LB39, highest enzyme activities were obtained in medium with 20 g/L of pectin and without glucose: 42 U/mL for endo-PG and 32 U/mL for exo-PG. In the conditions defined for the submerged process, different medium initial pH values were tested. Maximum activities were observed at initial pH of 3.0 for endo-PG (44 U/mL) and 4.0 for exo-PG (37 U/mL). Furthermore, in bench bioreactor, it was observed that an initial pH of 4.0, with uncontrolled minimum value and, afterwards, maximum value controlled at 3.5 led to the largest enzyme production with 81 U/mL of endo-PG and 49 U/mL of exo-PG. By comparing the enzymatic preparations produced by the selected strains, it was noticed that the pectinase produced by A. niger LB23 were more efficient for the hydrolysis of pectic substances present in both apple and bilberry juices, since it improved reduction of turbidity (90 and 40%) and viscosity (40 and 60%) and increasing clarification (90 and 55%), respectively. These results indicate the potential of A. niger LB23 pectinases for the enzymatic treatment of fruit juices, being remarkable that both the level of phenolic compounds and antioxidant capacity of juices were mostly preserved after treatment.
Book chapters on the topic "Pectinase enzyme"
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Dongowski, G., S. Förster, and H. Kunzek. "Effect of Pectolytic and Cellulolytic Enzyme Treatments on Functional and Nutritional Properties of Cell Wall Materials from Apples." In Advances in Pectin and Pectinase Research, 491–504. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-0331-4_36.
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Favela-Torres, Ernesto, Cristobal Aguilar, Juan Carlos Contreras-Esquivel, and Gustavo Viniegra-González. "Pectinases." In Enzyme Technology, 273–96. New York, NY: Springer New York, 2006. http://dx.doi.org/10.1007/978-0-387-35141-4_14.
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Tewari, Rupinder, Ram P. Tewari, and Gurinder S. Hoondal. "Microbial Pectinases." In Microbial Enzymes and Biotransformations, 191–208. Totowa, NJ: Humana Press, 2005. http://dx.doi.org/10.1385/1-59259-846-3:191.
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Lee, Jason T., and Kyle D. Brown. "Mannanase, α-galactosidase and pectinase: minor players or yet to be exploited?" In Enzymes in farm animal nutrition, 70–88. 3rd ed. Wallingford: CABI, 2022. http://dx.doi.org/10.1079/9781789241563.0005.
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Abstract This chapter describes the composition, chemical structure, modes of action, application and effects on animal performance of beta-mannanase, alpha-galactosidase and pectinase as feed additives in animal diets.
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Vohra, Anuja, and Reena Gupta. "Pectinases and their Biotechnological Applications." In Microbial Enzyme Technology in Food Applications, 145–61. Boca Raton, FL : CRC Press, [2016] | Series: Food biology series | “A science publishers book.”: CRC Press, 2017. http://dx.doi.org/10.1201/9781315368405-10.
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Gunjal, Aparna B., Neha N. Patil, and Sonali S. Shinde. "Pectinase in Degradation of Lignocellulosic Wastes." In Enzymes in Degradation of the Lignocellulosic Wastes, 71–103. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-44671-0_5.
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Benen, J. A. E., G. J. W. M. van Alebeek, A. G. J. Voragen, and J. Visser. "Mode of Action Analysis and Structure-Function Relationships of Aspergillus Niger Pectinolytic Enzymes." In Advances in Pectin and Pectinase Research, 235–56. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-0331-4_18.
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Antony, Cecil, Praveen Kumar Ghodke, and Saravanakumar Thiyagarajan. "The Role of Pectinases in Waste Valorization." In Enzymes in the Valorization of Waste, 127–53. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003187684-6.
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Voragen, A. G. J., P. J. H. Daas, and H. A. Schols. "Enzymes as tools for structural studies of pectins." In Bioactive Carbohydrate Polymers, 129–45. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-015-9572-8_11.
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de Vries, J. A., A. G. J. Voragen, F. M. Rombouts, and W. Pilnik. "Structural Studies of Apple Pectins with Pectolytic Enzymes." In ACS Symposium Series, 38–48. Washington, DC: American Chemical Society, 1986. http://dx.doi.org/10.1021/bk-1986-0310.ch004.
Full textConference papers on the topic "Pectinase enzyme"
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Doković, Vladimir, and Snežana Bogosavljević-Bošković. "ENZIMI U ISHRANI BROJLERA." In XXVII savetovanje o biotehnologiji. University of Kragujevac, Faculty of Agronomy, 2022. http://dx.doi.org/10.46793/sbt27.229d.
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The paper presents the most important aspects of the action of exogenous enzymes (amylase, xylanase, glucanase, cellulase, hemicellulase, pectinase, phytase and protease) added to broiler feed. The addition of broiler feed enzymes has nutritional, health, economic and environmental justification. The use of complexes of exogenous enzymes (enzyme cocktails) as additives to complete mixtures for feeding broiler chickens in different phases of fattening, significantly increases the availability of reserve polysaccharides, fats, proteins and some minerals, better energy efficiency from food, better health of chickens, better quality carcasses and chicken meat, reducing the cost of feeding fattening chickens (and thus the total cost of production), as well as reducing environmental pollution and is one of the easiest feasible alternatives to improve the profitability of production in poultry.
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Kabir, Md Fauzul, and Lu-Kwang Ju. "Temperature effects on enzyme stability for carbohydrate hydrolysis of soy materials." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/srjx5896.
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Carbohydrate makes up one-third of the soybean mass. The oligo-/poly-meric carbohydrate lowers the value of soy protein products. Carbohydrate-rich byproducts like soy molasses are undervalued without large-volume applications. It is highly desirable to selectively remove carbohydrate and convert it to monosaccharides, as good fermentation feedstock for making biofuels and bioproducts. Enzymatic hydrolysis is an environment-friendly method to accomplish these, but it requires a complex mixture of enzymes including at least a-galactosidase, sucrase, pectinase, cellulase, and xylanase. Further, while the hydrolysis benefits from being done at elevated temperatures for faster reaction rates, the high temperatures pose challenges to the stability of enzymes. Here we investigated the short-term and long-term effects of high temperatures on these enzymes, to determine their optimum temperatures. For the short-term effects, enzyme broths produced from Aspergillus niger fermentations were analyzed at different temperatures for individual enzyme activities (a-galactosidase, sucrase, ...). The enzyme-assisted Arrhenius model developed by DeLong et al., which considered the temperature effects on enzyme conformation, was used to fit the temperature-dependent activity and determine its short-term optimum temperature. For long-term stability effects, enzyme broths were incubated at multiple temperatures for up to 72 h, and samples were taken at different times and analyzed to follow the activity changes. Regression with kinetic degradation models using the time-dependent activity changes gave the best-fit degradation constant for each enzyme at each temperature. Fitting these constants with the Arrhenius law gave a model that incorporated both effects of temperature and time on enzyme activity. As an application example, we also evaluated the performance of soybean molasses hydrolysis at the selected optimum temperature where the reaction rate was fast enough while denaturation of a-galactosidase, the key enzyme for stachyose and raffinose hydrolysis, was not too fast. Detailed results and discussion will be presented.
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Hai-ning Zhang, Jia He, Dan Luo, Chun-yang Zheng, Gai-ping Zhai, and Shuo-guo Zhang. "Study on effect on pulp enzyme and pectinase on the juice yield of kiwi fruit." In 2011 International Conference on New Technology of Agricultural Engineering (ICAE). IEEE, 2011. http://dx.doi.org/10.1109/icae.2011.5943991.
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Alpiger, Simone Bleibach, and Milena Corredig. "Influence of Process Conditions on Enzyme Assisted Aqueous Extraction of Protein from Whole Rapeseed Using Pectinase." In Virtual 2021 AOCS Annual Meeting & Expo. American Oil Chemists’ Society (AOCS), 2021. http://dx.doi.org/10.21748/am21.51.
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SINGHAL, ANSHUL, AMY LANGHORST, MIHAELA BANU, and ALAN TAUB. "EFFECT OF ENZYMATIC RETTING CONDITIONS ON THE DIAMETER AND MECHANICAL PROPERTIES OF FLAX FIBERS." In Proceedings for the American Society for Composites-Thirty Seventh Technical Conference. Destech Publications, Inc., 2022. http://dx.doi.org/10.12783/asc37/36478.
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The current industrial method of extracting natural plant fibers, originally intended for their textile use, can degrade the inherent mechanical properties, making them difficult to replace e-glass fibers for reinforcement in polymer composites. Microorganisms during the initial dew/field retting step of fiber extraction process not only degrades the fiber-stem interphase bond constituting primarily pectin and lignin, but also degrades the structural components of the fiber such as cellulose, resulting in non-uniform technical fibers with poor mechanical properties. Also, current single fiber testing standards used for mechanical properties characterization of these fibers are suitable for assessing homogenous and uniform fiber properties correctly, which is not the case in natural fibers. In this study, the flax stems were treated with Pectinase Ultra SPL enzyme targeted to degrade the pectin bonds between the fibers and plant stem, without affecting the structural component cellulose. In this study, the size of technical fibers hand extracted from dew and enzyme retted flax are compared. The hand extracted enzyme retted stem fibers showed more uniform, finer diameters resulting in better tensile properties when compared with dew/field retted stem fibers. The improved properties are related to the diameter effect in which as the area of these fibers is reduced, the reduction of defects during the fiber extraction.
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Unluturk, S., S. Oncu, C. Tari, and N. Gogus. "Various Factors Affecting the Pellet Morphology, Broth Reology and Pectinase Enzyme Production in Submerged Fermentation of Aspergillus Sojae." In 13th World Congress of Food Science & Technology. Les Ulis, France: EDP Sciences, 2006. http://dx.doi.org/10.1051/iufost:20060271.
Full textReports on the topic "Pectinase enzyme"
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Lurie, Susan, John Labavitch, Ruth Ben-Arie, and Ken Shackel. Woolliness in Peaches and Nectarines. United States Department of Agriculture, 1995. http://dx.doi.org/10.32747/1995.7570557.bard.
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The overall goal of the research was to understand the processes involved in the development of woolliness in peaches and nectarines. Four specific hypotheses were proposed and in the course of the research evidence was gathered t support two of them and to not support two others. The hypotheses and a summary of the evidence are outlined below. 1. That woolliness arises from an imbalance between the activities of the cell wall pectin degrading enzymes. Using 'Flavortop' nectarines and 'Hermoza' peaches as model systems, storage regimes were manipulated to induce or prevent woolliness. The expression (mRNA abundance), protein content (Western blotting), and activity of polygalacturonase (PG) and pectin esterase (PE) were followed. Expression of the enzymes was not different, but activity and the ratio between PG and PE activities were quite different in fruits developing woolliness or ripening normally. This was also examined by looking at the substrate, the pectin moiety of the cell wall, and i woolly fruit there were more high molecular weight pectins with regions of non-methylated galacturonic acid residues. Taking an in vitro approach it was found a) that PE activity was stable at 0oC while PG activity decreased; b) incubating the calcium pectate fraction of the cell wall with PE extracted from peaches caused the polymers to form a gel characteristic of the visual woolly symptoms in peaches. 2. That continued cell wall synthesis occurs during storage and contributes to structural changes i cell walls and improper dissolution and softening after storage. We tried to adapt our technique of adding 13C-glucose to fruit discs, which was used successfully to follow cell wall synthesis during tomato ripening. However, the difference in sugar content between the two fruits (4% in tomato and 12% in peach) meant that the 13C-glucose was much more diluted within the general metabolite pool. We were unable to see any cell wall synthesis which meant that either the dilution factor was too great, or that synthesis was not occurring. 3. That controlled atmosphere (CA) prevents woolliness by lowering all enzyme activities. CA was found to greatly reduce mRNA abundance of the cell wall enzymes compared to regular air storage. However, their synthesis and activity recovered during ripening after CA storage and did not after regular air storage. Therefore, CA prevented the inhibition of enzyme activation found in regular air storage. 4. That changes in cell wall turgor and membrane function are important events in the development of woolliness. Using a micro pressure probe, turgor was measured in cells of individual 'O'Henry' and 'CalRed' peaches which were woolly or healthy. The relationship between firmness and turgor was the same in both fruit conditions. These data indicate that the development and expression of woolliness are not associated with differences in membrane function, at least with regard to the factors that determine cell turgor pressure. In addition, during the period of the grant additional areas were explored. Encoglucanase, and enzyme metabolizing hemicellulose, was found to be highly expressed air stored, but not in unstored or CA stored fruit. Activity gels showed higher activity in air stored fruit as well. This is the first indication that other components of the cell wall may be involved in woolliness. The role of ethylene in woolliness development was also investigated at it was found a) that woolly fruits had decreased ability to produce ethylene, b) storing fruits in the presence of ethylene delayed the appearance of woolliness. This latter finding has implication for an inexpensive strategy for storing peaches and nectarines.
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Joel, Daniel M., John C. Steffens, and Alfred M. Mayer. Host-Elicited Germination and Mechanism of Penetration in Broomrape (Orobanche Spp.). United States Department of Agriculture, August 1993. http://dx.doi.org/10.32747/1993.7568107.bard.
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Orobanche is an important parasitic weed. For developing novel methods for its control, a thorough understanding of crucial stages of its development is needed. Therefore, the objectives of this project were characterization of Orobanche germination stimulants, analysis of mechanisms of haustorial penetration, and characterization and isolation of penetration enzymes. The first highly potent natural germination stimulant for Orobanche was isolated from sunflower and identified by high-field 1D (1H and 13C), 2D (1H-1H COSY, HMQC, HMBC)-NMR, GC.FT-IR, and GC.MS as costuslactone, a guaiane type sesquiterpene lactone that resembles strigol only in possessing a lactone moiety that is required for activity. The first direct in situ evidence for the enzymatic nature of the infection process of a parasitic angiosperm was established. Pectin deesterification and depletion of pectins in host cell walls were shown adjacent to haustorial cells. Pectin methyl esterase and polygalacturonase were immunocytochemically detected in intrusive cells and in adjacent host apoplast. Orobanche tissues contain inhibitors of PGase activity. PME and three PGases were isolated from Orobanche calli. PME was characterized and purified, and antibodies were prepared against it. This study presents novel findings regarding parasitism in Orobanche, which may help to open up new approaches for controlling broomrapes.