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Enzymatic hydrolysis

Zongwei Guo, Zhe Ling, Chao Wang, Xueming Zhang, Feng Xu
In this study, a novel biomass pretreatment process using three kinds of deep eutectic solvents (DESs) was developed to improve saccharification efficiency and lignin valorization. The major components of xylose residue including cellulose and lignin fractions were released, recovered and utilized. Pretreatment with betaine/lactic acid system at 120 °C for 2 h was found to be the optimal conditions with prominently increased enzymatic digestibility (from 55.3% to 96.8%). The efficient conversion was mainly ascribed to the significant delignification efficiency of 81...
June 12, 2018: Bioresource Technology
Ruifan Jiang, Yibin Qiu, Weiwei Huang, Li Zhang, Feng Xue, Hao Ni, Difen Mei, Jian Gao, Hong Xu
Inulo-oligosaccharides (IOSs), a novel food additive and health product, represent a promising alternative to antibiotics. As prebiotics, IOSs can be obtained from inulin by endo-inulinase-mediated hydrolysis. Nonetheless, enzymatic catalysis is not feasible industrially because of the required catalytic conditions and cost. In this study, a 2331-bp optimized gene inuQ (from Pseudomonas mucidolens) encoding endo-inulinase was cloned into shuttle vector PHY300PLK and transfected into Bacillus subtilis WB800-R, with the simultaneous deletion of gene sacC encoding levanase...
June 18, 2018: Applied Biochemistry and Biotechnology
Yanyan Qin, Bin Jian, Gang Guo, Yingfang Niu
OBJECTIVE: To develop a method for determination of bisphenol A in human blood by fast phospholipid removal solid phase extraction method-ultra performance liquid chromatography tandem mass spectrometry( UPLC-MS/MS). METHODS: Enzymatic hydrolysis( β-glucuronidase/arylsulfatase) and phospholipid removal solid phase extraction were used to treat the blood samples under the acidic condition, a Infinity Lab Poroshell 120 PFP column( 100 mm × 3. 0 mm, 2. 7 μm) was used for LC separation, ESI negative ion scan was used with multiple reaction monitoring( MRM) mode...
January 2018: Wei Sheng Yan Jiu, Journal of Hygiene Research
Liyuan Wang, Yan Zou, Pinggu Wu, Tianbin Bian, Ying Ying, Tianjiao Wang, Zhengyan Hu, Jun Tang
OBJECTIVE: A method for the determination of 5 kinds of phthalate monoesters in urine by solid-phase extraction and gas chromatography-mass spectrometry was developed. METHODS: After urine enzymatic hydrolysis by β-glucuronidase, the sample was pretreated by SPE. Phthalate monoesters were eluted by boron trifluoridemethanol complex, and determined by gas chromatograph-mass spectrometer with DB-5 ms Phenomenex( 30 m × 0. 25 mm, 0. 25 μm). RESULTS: Within the concentration range of25...
November 2017: Wei Sheng Yan Jiu, Journal of Hygiene Research
Mariusz Kuglarz, Merlin Alvarado-Morales, Katarzyna Dąbkowska, Irini Angelidaki
The aim of this study was to develop an integrated biofuel (cellulosic bioethanol) and biochemical (succinic acid) production process from rapeseed straw after dilute-acid pretreatment. Rapeseed straw pretreatment at 20% (w/v) solid loading and subsequent hydrolysis with Cellic® CTec2 resulted in high glucose yield (80%) and ethanol output (122-125 kg of EtOH/Mg of rapeseed straw). Supplementation the enzymatic process with 10% dosage of endoxylanases (Cellic® HTec2) reduced the hydrolysis time required to achieve the maximum glucan conversion by 44-46% and increased the xylose yield by 10% compared to the process with Cellic® CTec2...
May 29, 2018: Bioresource Technology
Duleepa Pathiraja, Saeyoung Lee, In-Geol Choi
3,6-Anhydro-L-galactose (L-AHG) is a bioactive constituent of agar polysaccharides. To be used as a cosmetic or pharmaceutical ingredient, L-AHG is more favorably prepared by enzymatic saccharification of agar using a combination of agarolytic enzymes. Determining the optimum enzyme combination from natural repertoire is a bottleneck for designing an efficient enzymatic hydrolysis process. We consider all theoretical enzymatic saccharification routes in the natural agarolytic pathway of a marine bacterium, Saccharophagus degradans 2-40...
June 13, 2018: Journal of Agricultural and Food Chemistry
Miriam P Koetzler, Kyle Robinson, Hong-Ming Chen, Mark Okon, Lawrence P McIntosh, Stephen G Withers
Understanding the detailed mechanisms of enzyme-catalyzed hydrolysis of the glycosidic bond is fundamentally important, not only to the design of tailored cost-efficient, stable and specific catalysts, but also to the development of specific glycoside hydro-lase inhibitors as therapeutics. Retaining glycosidases employ two key carboxylic acid residues, typically glutamic acids, in a double-displacement mechanism involving a covalent glycosyl-enzyme intermediate. One Glu functions as a nucleophile while the other acts as a general acid/base...
June 12, 2018: Journal of the American Chemical Society
Violeta T Pardío, Argel Flores, Karla M López, David I Martínez, Ofelia Márquez, Krzysztof N Waliszewski
Endogenous and exogenous enzymatic hydrolysis carried out to obtain vanilla extracts with higher concentrations of vanillin using green vanilla beans. Sequences initiated with freezing of green vanilla beans at - 1 °C for 24 h, followed by endogenous hydrolysis under optimal β-glucosidase activity at 4.2 and 35 °C for 96 h, exogenous hydrolysis with Crystalzyme PML-MX at pH 5.0 and 40 °C for 72 h, and ethanol extraction at 40% (v v-1 ) for 30 days. In the proposed method, 200 g of fresh green vanilla beans with 84% moisture (32 g dry base) were used to obtain a liter of single fold vanilla extract...
June 2018: Journal of Food Science and Technology
Alexander Gissibl, Andrew Care, Lindsay M Parker, Sameera Iqbal, Graham Hobba, Helena Nevalainen, Anwar Sunna
A hydrothermal microwave pretreatment was established to facilitate the enzymatic production of soluble bioactive β-1,3-glucans from the recalcitrant substrate paramylon. The efficacy of this pretreatment was monitored with a newly developed direct Congo Red dye-based assay over a range of temperatures. Microwave pretreatment at 170 °C for 2 min resulted in a significantly enhanced enzymatic hydrolysis of paramylon. The action of endo-β-1,3- and exo- β-1,3-glucanases on the microwave-pretreated paramylon produced soluble β-1,3-glucans with degrees of polymerisation (DP) ranging from 2-59 and 2-7, respectively...
September 15, 2018: Carbohydrate Polymers
Haiyan Zhang, Junbao Li, Guangqun Huang, Zengling Yang, Lujia Han
A thorough assessment of the microstructural changes and synergistic effects of hydrothermal and/or ultrafine grinding pretreatment on the subsequent enzymatic hydrolysis of corn stover was performed in this study. The mechanism of pretreatment was elucidated by characterizing the particle size, specific surface area (SSA), pore volume (PV), average pore size, cellulose crystallinity (CrI) and surface morphology of the pretreated samples. In addition, the underlying relationships between the structural parameters and final glucose yields were elucidated, and the relative significance of the factors influencing enzymatic hydrolyzability were assessed by principal component analysis (PCA)...
May 26, 2018: Bioresource Technology
Hongdan Zhang, Gaojin Lyu, Aiping Zhang, Xin Li, Jun Xie
An efficient pretreatment with various concentrations of FeCl3 (0.005-0.2 mol/L) was developed to extract hemicellulose in sugarcane bagasse and enhance the enzymatic hydrolysis of cellulose in pretreated solids. It was found that 0.025 mol/L FeCl3 pretreated substrate yielded a high glucose yield of 80.1% during enzymatic hydrolysis. Then the characterization of raw material and pretreated solids was carried out to better understand how hemicellulose removal affected subsequent enzymatic hydrolysis. In addition, Tween 80 and Bovine Serum Albumin (BSA) were added to promote enzymatic hydrolysis of pretreated substrate...
June 1, 2018: Bioresource Technology
Simel Bağder Elmacı, Filiz Özçelik
In this study, it was aimed to enhance the enzymatic hydrolysis of recalcitrant yellow pine wood and subsequently to produce ethanol efficiently through the application of 1-ethyl-3-methylimidazolium acetate (EMIMAc) ionic liquid. The effect of biomass particle size (<2.5 mm, 500-850 μm, 363-500 μm and <363 μm) prior to pretreatment and pretreatment time (15, 30 and 45 min) on the structural properties and enzymatic hydrolysis yield of EMIMAc pretreated pine wood were also investigated. In general, EMIMAc functioned more efficiently at larger biomass particle sizes compared to smaller ones...
June 9, 2018: Biotechnology Progress
Hongliang Guo, Xiao-Dong Wang, Duu-Jong Lee
Protective action of lignin/hemicellulose networks and crystalline structures of embedded cellulose render lignocellulose material resistant to external enzymatic attack. To eliminate this bottleneck, research has been conducted in which advanced proteomic techniques are applied to identify effective commercial hydrolytic enzymes. This mini-review summarizes researches on lignocellulose-degrading enzymes, the mechanisms of the responses of various lignocellulose-degrading strains and microbial communities to various carbon sources and various biomass substrates, post-translational modifications of lignocellulose-degrading enzymes, new lignocellulose-degrading strains, new lignocellulose-degrading enzymes and a new method of secretome analysis...
May 31, 2018: Bioresource Technology
Ornella M Ontañon, Silvina Ghio, Rubén Marrero Díaz de Villegas, Florencia E Piccinni, Paola M Talia, María L Cerutti, Eleonora Campos
Biomass hydrolysis constitutes a bottleneck for the biotransformation of lignocellulosic residues into bioethanol and high-value products. The efficient deconstruction of polysaccharides to fermentable sugars requires multiple enzymes acting concertedly. GH43 β-xylosidases are among the most interesting enzymes involved in hemicellulose deconstruction into xylose. In this work, the structural and functional properties of β-xylosidase EcXyl43 from Enterobacter sp. were thoroughly characterized. Molecular modeling suggested a 3D structure formed by a conserved N-terminal catalytic domain linked to an ancillary C-terminal domain...
June 6, 2018: Applied Microbiology and Biotechnology
Muhammed Majeed, Shaheen Majeed, Kalyanam Nagabhushanam, Sivakumar Arumugam, Sankaran Natarajan, Kirankumar Beede, Furqan Ali
Health benefits of dietary fibers are currently being widely recognized. However, the assessment of dietary fiber as a prebiotic is essential and also important for the development of an improved synbiotic commercial preparation. Thus, the aim of this study was to evaluate the potential of galactomannan extracted from fenugreek seeds as a prebiotic fiber and also its fermentation by the probiotic strain Bacillus coagulans MTCC 5856. Nondigestibility by the gastric acid and pancreatic enzyme hydrolysis of galactomannan were determined using an in vitro model mimicking the in vivo conditions...
May 2018: Food Science & Nutrition
Crina Anastasescu, Silviu Preda, Adriana Rusu, Dana Culita, Gabriel Plavan, Stefan Strungaru, Jose Maria Calderon-Moreno, Cornel Munteanu, Catalina Gifu, Mirela Enache, Radu Socoteanu, Daniel Angelescu, Mihai Anastasescu, Mariuca Gartner, Ioan Balint, Maria Zaharescu
A wide range of hybrid biomaterials has been designed in order to sustain bioremediation processes by associating sol-gel SiO₂ matrices with various biologically active compounds (enzymes, antibodies). SiO₂ is a widespread, chemically stable and non-toxic material; thus, the immobilization of enzymes on silica may lead to improving the efficiency of biocatalysts in terms of endurance and economic costs. Our present work explores the potential of different hybrid morphologies, based on hollow tubes and solid spheres of amorphous SiO₂, for enzyme immobilization and the development of competitive biocatalysts...
June 5, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Shu-Ying Xu, Jie Kan, Zhong Hu, Yang Liu, Hong Du, Guang-Chang Pang, Kit-Leong Cheong
Neoagaro-oligosaccharides (NAOS) have health benefits that are related to their amount and degree of polymerization (DP). However, the current methods that are used to quantify enzymatically released NAOS are un-specific and time-consuming. Agar has been extracted from Gelidium amansii and has been degraded by AgaXa (a recombinant β-agarase). Polysaccharide analysis using carbohydrate gel electrophoresis (PACE) has been adapted in order to quantify NAOS. In addition, the anti-oxidant activity of the degraded samples has been assessed...
June 5, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Leehyeon Kim, Do Hoon Kwon, Bong Heon Kim, Jiyeon Kim, Mi Rae Park, Zee-Yong Park, Hyun Kyu Song
Conventional ubiquitylation occurs through an ATP-dependent three-enzyme cascade (E1, E2, and E3) that mediates the covalent conjugation of the C-terminus of ubiquitin to a lysine on the substrate. SdeA, which belongs to the SidE effector family of Legionella pneumophila, can transfer ubiquitin to endoplasmic reticulum-associated Rab-family GTPases in a manner independent of E1 and E2 enzymes. The novel ubiquitin-modifying enzyme SdeA utilizes NAD+ as a cofactor to attach ubiquitin to a serine residue of the substrate...
June 2, 2018: Journal of Molecular Biology
Hong Fang, Gurshagan Kandhola, Kalavathy Rajan, Angele Djioleu, Danielle Julie Carrier, Kendall R Hood, Elizabeth E Hood
Loblolly pine residues have enormous potential to be the raw material for advanced biofuel production due to extensive sources and high cellulose content. Hot water (HW) pretreatment, while being a relatively economical and clean technology for the deconstruction of lignocellulosic biomass, could also inhibit the ensuing enzymatic hydrolysis process because of the production of inhibitors. In this study, we investigated the effect of oligosaccharide fractions purified from HW pre-hydrolyzate of pinewood using centrifugal partition chromatography (CPC) on three recombinant cellulolytic enzymes (E1, CBHI and CBHII), which were expressed in the transgenic corn grain system...
2018: Frontiers in Bioengineering and Biotechnology
Dustin R Middleton, Amy V Paschall, Jeremy A Duke, Fikri Y Avci
Despite a century of investigation, Streptococcus pneumoniae ( Spn ) remains a major human pathogen, causing a number of diseases such as pneumonia, meningitis, and otitis media. Like many encapsulated pathogens, the capsular polysaccharide (CPS) of Spn is a critical component for colonization and virulence in mammalian hosts. This study aimed to evaluate the protective role of a glycoside hydrolase, Pn3Pase, targeting the CPS of type 3 Spn , which is one of the most virulent serotypes. We have assessed the ability of Pn3Pase to degrade the capsule on a live type 3 strain...
June 4, 2018: Infection and Immunity
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