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Paul Christakopoulos - One of the best experts on this subject based on the ideXlab platform.
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enzymic production of feruloyl xylo oligosaccharides from Corn Cobs by a family 10 xylanase from thermoascus aurantiacus
Lwt - Food Science and Technology, 2008Co-Authors: Petros Katapodis, Paul ChristakopoulosAbstract:Abstract Feruloyl xylo-oligosaccharides (FeXOSs) were obtained from Corn Cobs (CCs) by treatment with a Thermoascus aurantiacus family 10-β- d -endoxylanase. CCs subjected to a sonication (ST-CC) or an autoclave treatment in order to enhance enzymic access and FeXOS production. Enzymic FeXOS production was increased by CCs thermal treatment up to 3.5 times. The kinetic parameters KE and Vmax, describing enzyme-dependent production rates of FeXOSs from CCs, were estimated at 130±20 nM and 290±10 nM h−1, respectively. The reaction parameters affecting the FeXOS production, such as substrate concentration, enzyme loading and reaction time, have been investigated. The maximum FeXOS production was observed after 24 h incubation of 100 g L−1 AT-CC with 570 nM xylanase. The obtained yield was 12 μmol of FeXOSs per gram of CC.
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production of phenolics from Corn Cobs by coupling enzymic treatment and solid state fermentation
Engineering in Life Sciences, 2004Co-Authors: Evangelos Topakas, E Kalogeris, Dimitris Kekos, B J Macris, Paul ChristakopoulosAbstract:A two-stage process that combined solid-state fermentation (SSF) and subsequent enzymic treatment was used in order to release p-coumaric (p-CA) and ferulic acid (FA) from Corn Cobs. Sporotrichum thermophile was grown on Corn Cobs under SSF conditions, and the production of cinnamoyl esterases and xylanases was studied over 7 days. The time course of enzyme production showed a maximum activity of 1483 nkat/g, 0.3 nkat/g and 0.067 nkat/g for xylanase, feruloyl esterase, and p-coumaroyl esterase, respectively. The importance of the moisture level of the growth substrate was discussed. After SSF, the fermented substrate was directly exposed to autohydrolysis and the in situ produced multienzyme system was successfully used for the partial degradation of cell wall components and the liberation of p-CA and FA. A yield of 0.85 g/kg and 0.38 g/kg FA and p-CA, respectively, of dry matter of Corn Cobs was obtained.
Suren Singh - One of the best experts on this subject based on the ideXlab platform.
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secretome analysis of the thermophilic xylanase hyper producer thermomyces lanuginosus ssbp cultivated on Corn Cobs
Journal of Industrial Microbiology & Biotechnology, 2014Co-Authors: Alison M Winger, Joshua L Heazlewood, Leanne Jade G Chan, Christopher J Petzold, Kugenthiren Permaul, Suren SinghAbstract:Thermomyces lanuginosus is a thermophilic fungus known for its ability to produce industrially important enzymes including large amounts of xylanase, the key enzyme in hemicellulose hydrolysis. The secretome of T. lanuginosus SSBP was profiled by shotgun proteomics to elucidate important enzymes involved in hemicellulose saccharification and to characterise the presence of other industrially interesting enzymes. This study reproducibly identified a total of 74 proteins in the supernatant following growth on Corn Cobs. An analysis of proteins revealed nine glycoside hydrolase (GH) enzymes including xylanase GH11, β-xylosidase GH43, β-glucosidase GH3, α-galactosidase GH36 and trehalose hydrolase GH65. Two commercially produced Thermomyces enzymes, lipase and amylase, were also identified. In addition, other industrially relevant enzymes not currently explored in Thermomyces were identified including glutaminase, fructose-bisphosphate aldolase and cyanate hydratase. Overall, these data provide insight into the novel ability of a cellulase-free fungus to utilise lignocellulosic material, ultimately producing a number of enzymes important to various industrial processes.
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production of β xylanase by a thermomyces lanuginosus mc 134 mutant on Corn Cobs and its application in biobleaching of bagasse pulp
Journal of Bioscience and Bioengineering, 2009Co-Authors: Kuttanpillai Santhosh Kumar, Ayyachamy Manimaran, Kugen Permaul, Suren SinghAbstract:Abstract The production of hemicellulases by Thermomyces lanuginosus SK using oatspelts xylan was examined during submerged cultivation. A high level of extracellular xylanase (346 ± 10 U ml − 1 ) production was observed on the fifth day; however, accessory enzyme levels were low. T. lanuginosus SK was further subjected to UV and N -methyl- N -nitro- N -nitrosoguanidine mutagenesis. The T. lanuginosus MC 134 mutant showed a 1.5 fold increase in xylanase production on oatspelts xylan, compared to the wild type strain. Xylanase production was further enhanced to 3299 ± 95 U ml − 1 by using Corn Cobs under optimized growth conditions. A reduction in xylanase production was observed in a 5 L fermenter. Also, the biobleaching efficiency of crude xylanase was evaluated on bagasse pulp, and a brightness of 46.07 ± 0.05% was observed with the use of 50 U of crude xylanase per gram of pulp. This brightness was 3.6 points higher than that of the untreated samples. Reducing sugars (25.78 ± 0.14 mg g − 1 ) and UV-absorbing lignin-derived compound values were considerably higher in xylanase-treated samples. T. lanuginosus MC 134 has a potential application in the pulp and paper industries.
E Gueguim B Kana - One of the best experts on this subject based on the ideXlab platform.
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simultaneous saccharification and bioethanol production from Corn Cobs process optimization and kinetic studies
Bioresource Technology, 2018Co-Authors: Yeshona Sewsynkersukai, E Gueguim B KanaAbstract:Abstract This study investigates the simultaneous saccharification and fermentation (SSF) process for bioethanol production from Corn Cobs with prehydrolysis (PSSF) and without prehydrolysis (OSSF). Two response surface models were developed with high coefficients of determination (>0.90). Process optimization gave high bioethanol concentrations and bioethanol conversions for the PSSF (36.92 ± 1.34 g/L and 62.36 ± 2.27%) and OSSF (35.04 ± 0.170 g/L and 58.13 ± 0.283%) models respectively. Additionally, the logistic and modified Gompertz models were used to study the kinetics of microbial cell growth and ethanol formation under microaerophilic and anaerobic conditions. Cell growth in the OSSFmicroaerophilic process gave the highest maximum specific growth rate (µmax) of 0.274 h−1. The PSSFmicroaerophilic bioprocess gave the highest potential maximum bioethanol concentration (Pm) (42.24 g/L). This study demonstrated that microaerophilic rather than anaerobic culture conditions enhanced cell growth and bioethanol production, and that additional prehydrolysis steps do not significantly impact on the bioethanol concentration and conversion in SSF process.
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development of a sequential alkalic salt and dilute acid pretreatment for enhanced sugar recovery from Corn Cobs
Energy Conversion and Management, 2018Co-Authors: Yeshona Sewsynkersukai, Terence N Suinyuy, E Gueguim B KanaAbstract:Abstract This study presents a sequential sodium phosphate dodecahydrate (Na3PO4·12H2O) and sulfuric acid (H2SO4) pretreatment to enhance sugar release from Corn Cobs. The effects of Na3PO4·12H2O concentration, H2SO4 concentration and solid to liquid ratio on the reducing sugar yield were investigated. The developed model had a coefficient of determination value (R2) of 0.98. Maximum reducing sugar yield of 0.99 ± 0.01 g/g was obtained with 12.70% Na3PO4·12H2O, 1.04% H2SO4 and 14.49% solid to liquid ratio. A 9-fold increase in the sugar yield was observed compared to previous reports on Corn Cobs. An intelligent model was developed to determine functional relationships between the input and output parameters. Reducing sugar yield was majorly dependent on Na3PO4·12H2O concentration and fits a Weibull type of relationship. Sequential pretreatment of lignocellulosic material with alkalic salt and dilute acid significantly enhanced sugar recovery and demonstrated high efficiency for microbial production of biofuels and bioproducts.
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optimization of a novel sequential alkalic and metal salt pretreatment for enhanced delignification and enzymatic saccharification of Corn Cobs
Bioresource Technology, 2017Co-Authors: Yeshona Sewsynkersukai, E Gueguim B KanaAbstract:Abstract This study presents a sequential sodium phosphate dodecahydrate (Na 3 PO 4 ·12H 2 O) and zinc chloride (ZnCl 2 ) pretreatment to enhance delignification and enzymatic saccharification of Corn Cobs. The effects of process parameters of Na 3 PO 4 ·12H 2 O concentration (5–15%), ZnCl 2 concentration (1–5%) and solid to liquid ratio (5–15%) on reducing sugar yield from Corn Cobs were investigated. The sequential pretreatment model was developed and optimized with a high coefficient of determination value (0.94). Maximum reducing sugar yield of 1.10 ± 0.01 g/g was obtained with 14.02% Na 3 PO 4 ·12H 2 O, 3.65% ZnCl 2 and 5% solid to liquid ratio. Scanning electron microscopy (SEM) and Fourier Transform Infrared analysis (FTIR) showed major lignocellulosic structural changes after the optimized sequential pretreatment with 63.61% delignification. In addition, a 10-fold increase in the sugar yield was observed compared to previous reports on the same substrate. This sequential pretreatment strategy was efficient for enhancing enzymatic saccharification of Corn Cobs.
Raniere Fagundes Melosilveira - One of the best experts on this subject based on the ideXlab platform.
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antiproliferative xylan from Corn Cobs induces apoptosis in tumor cells
Carbohydrate Polymers, 2019Co-Authors: Raniere Fagundes Melosilveira, Rony Lucas Silva Viana, Rodrigo A Da Silva, Daisy Machado, Diego Araujo Sabry, Ana Karina Lima Nascimento, Katia Castanho Scortecci, Carmen Verissima Ferreirahalder, Guilherme L Sassaki, Hugo Alexandre Oliveira RochaAbstract:Abstract Xylan is one of the most abundant hemicellulose constituents in the plant kingdom. We extracted xylan from Corn Cobs (XCC) using ultrasound. The structure of XCC was determined by NMR analysis, which revealed a composition of xylose:glucose:arabinose:galactose:mannose:glucuronic acid in a molar percentage ratio of 48:21:16:10:2.5:2.5. XCC induced the proliferation of murine macrophage cells (RAW 264.7) and inhibited the proliferation of human lung adenocarcinoma epithelial cells (A549) by 20% and human cervical adenocarcinoma cells (HeLa) by 60%. Several cell death-associated morphological changes were observed after the exposure of HeLa cells to XCC for 24 h. In addition, by using fluorescent probes, we observed a larger number of irregular and pyknotic nuclei with condensed chromatin bodies (nuclear condensation). FACS analysis showed an increase in the number of annexin V-positive and propidium iodide (PI)-positive cells (37.0%) in the presence of XCC compared with that of the negative control cells (5.0%). XCC also increased the ratio of Bax:Bcl-2 (3.5:1) and the levels of cytochrome c, caspase 3, and apoptosis-inducing factor (AIF) in treated cells. Therefore, the results demonstrated the antiproliferative potential of XCC, which induced apoptosis in HeLa cells.
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antioxidant and antiproliferative activities of methanolic extract from a neglected agricultural product Corn Cobs
Molecules, 2014Co-Authors: Raniere Fagundes Melosilveira, Gabriel Pereira Fidelis, Rony Lucas Silva Viana, Vinicius Campelo Soeiro, Rodrigo A Da Silva, Daisy Machado, Leandro Silva Costa, Carmen Verissima Ferreira, Hugo Alexandre Oliveira RochaAbstract:Neglected agricultural products (NAPs) are defined as discarded material in agricultural production. Corn Cobs are a major waste of agriculture maize. Here, a methanolic extract from Corn Cobs (MEC) was obtained. MEC contains phenolic compounds, protein, carbohydrates (1.4:0.001:0.001). We evaluated the in vitro and in vivo antioxidant potential of MEC. Furthermore, its antiproliferative property against tumor cells was assessed through MTT assays and proteins related to apoptosis in tumor cells were examined by western blot. MEC showed no hydroxyl radical scavenger capacity, but it showed antioxidant activity in Total Antioxidant Capacity and DPPH scavenger ability assays. MEC showed higher Reducing Power than ascorbic acid and exhibited high Superoxide Scavenging activity. In tumor cell culture, MEC increased catalase, metallothionein and superoxide dismutase expression in accordance with the antioxidant tests. In vivo antioxidant test, MEC restored SOD and CAT, decreased malondialdehyde activities and showed high Trolox Equivalent Antioxidant Capacity in animals treated with CCl4. Furthermore, MEC decreased HeLa cells viability by apoptosis due an increase of Bax/Bcl-2 ratio, caspase 3 active. Protein kinase C expression increased was also detected in treated tumor cells. Thus, our findings pointed out the biotechnological potential of Corn Cobs as a source of molecules with pharmacological activity.
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in vitro antioxidant anticoagulant and antimicrobial activity and in inhibition of cancer cell proliferation by xylan extracted from Corn Cobs
International Journal of Molecular Sciences, 2011Co-Authors: Raniere Fagundes Melosilveira, Gabriel Pereira Fidelis, Mariana Santana Santos Pereira Costa, Cinthia Beatrice Silva Telles, Nednaldo Dantassantos, Susana De Oliveira Elias, Vanessa Bley Ribeiro, Afonso Luis Barth, Alexandre Jose Macedo, Edda Lisboa LeiteAbstract:Xylan is one of most abundant polymer after cellulose. However, its potential has yet to be completely recognized. Corn Cobs contain a considerable reservoir of xylan. The aim of this work was to study some of the biological activities of xylan obtained from Corn Cobs after alkaline extraction enhanced by ultrasonication. Physical chemistry and infrared analyses showed 130 kDa heteroxylan containing mainly xylose:arabinose: galactose:glucose (5.0:1.5:2.0:1.2). Xylan obtained exhibited total antioxidant activity corresponding to 48.5 mg of ascorbic acid equivalent/g of xylan. Furthermore, xylan displayed high ferric chelating activity (70%) at 2 mg/mL. Xylan also showed anticoagulant activity in aPTT test. In antimicrobial assay, the polysaccharide significantly inhibited bacterial growth of Klebsiella pneumoniae. In a test with normal and tumor human cells, after 72 h, only HeLa tumor cell proliferation was inhibited (p < 0.05) in a dose-dependent manner by xylan, reaching saturation at around 2 mg/mL, whereas 3T3 normal cell proliferation was not affected. The results suggest that it has potential clinical applications as antioxidant, anticoagulant, antimicrobial and antiproliferative compounds.
Hugo Alexandre Oliveira Rocha - One of the best experts on this subject based on the ideXlab platform.
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antiproliferative xylan from Corn Cobs induces apoptosis in tumor cells
Carbohydrate Polymers, 2019Co-Authors: Raniere Fagundes Melosilveira, Rony Lucas Silva Viana, Rodrigo A Da Silva, Daisy Machado, Diego Araujo Sabry, Ana Karina Lima Nascimento, Katia Castanho Scortecci, Carmen Verissima Ferreirahalder, Guilherme L Sassaki, Hugo Alexandre Oliveira RochaAbstract:Abstract Xylan is one of the most abundant hemicellulose constituents in the plant kingdom. We extracted xylan from Corn Cobs (XCC) using ultrasound. The structure of XCC was determined by NMR analysis, which revealed a composition of xylose:glucose:arabinose:galactose:mannose:glucuronic acid in a molar percentage ratio of 48:21:16:10:2.5:2.5. XCC induced the proliferation of murine macrophage cells (RAW 264.7) and inhibited the proliferation of human lung adenocarcinoma epithelial cells (A549) by 20% and human cervical adenocarcinoma cells (HeLa) by 60%. Several cell death-associated morphological changes were observed after the exposure of HeLa cells to XCC for 24 h. In addition, by using fluorescent probes, we observed a larger number of irregular and pyknotic nuclei with condensed chromatin bodies (nuclear condensation). FACS analysis showed an increase in the number of annexin V-positive and propidium iodide (PI)-positive cells (37.0%) in the presence of XCC compared with that of the negative control cells (5.0%). XCC also increased the ratio of Bax:Bcl-2 (3.5:1) and the levels of cytochrome c, caspase 3, and apoptosis-inducing factor (AIF) in treated cells. Therefore, the results demonstrated the antiproliferative potential of XCC, which induced apoptosis in HeLa cells.
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antioxidant and antiproliferative activities of methanolic extract from a neglected agricultural product Corn Cobs
Molecules, 2014Co-Authors: Raniere Fagundes Melosilveira, Gabriel Pereira Fidelis, Rony Lucas Silva Viana, Vinicius Campelo Soeiro, Rodrigo A Da Silva, Daisy Machado, Leandro Silva Costa, Carmen Verissima Ferreira, Hugo Alexandre Oliveira RochaAbstract:Neglected agricultural products (NAPs) are defined as discarded material in agricultural production. Corn Cobs are a major waste of agriculture maize. Here, a methanolic extract from Corn Cobs (MEC) was obtained. MEC contains phenolic compounds, protein, carbohydrates (1.4:0.001:0.001). We evaluated the in vitro and in vivo antioxidant potential of MEC. Furthermore, its antiproliferative property against tumor cells was assessed through MTT assays and proteins related to apoptosis in tumor cells were examined by western blot. MEC showed no hydroxyl radical scavenger capacity, but it showed antioxidant activity in Total Antioxidant Capacity and DPPH scavenger ability assays. MEC showed higher Reducing Power than ascorbic acid and exhibited high Superoxide Scavenging activity. In tumor cell culture, MEC increased catalase, metallothionein and superoxide dismutase expression in accordance with the antioxidant tests. In vivo antioxidant test, MEC restored SOD and CAT, decreased malondialdehyde activities and showed high Trolox Equivalent Antioxidant Capacity in animals treated with CCl4. Furthermore, MEC decreased HeLa cells viability by apoptosis due an increase of Bax/Bcl-2 ratio, caspase 3 active. Protein kinase C expression increased was also detected in treated tumor cells. Thus, our findings pointed out the biotechnological potential of Corn Cobs as a source of molecules with pharmacological activity.