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Enzymatic hydrolysis

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https://www.readbyqxmd.com/read/28214697/characterization-of-white-poplar-and-eucalyptus-after-ionic-liquid-pretreatment-as-a-function-of-biomass-loading-using-x-ray-diffraction-and-small-angle-neutron-scattering
#1
Xueming Yuan, Yonghao Duan, Lilin He, Seema Singh, Blake Simmons, Gang Cheng
A systematic study was performed to understand interactions among biomass loading during ionic liquid (IL) pretreatment, biomass type and biomass structures. White poplar and eucalyptus samples were pretreated using 1-ethyl-3-methylimidazolium acetate (EmimOAc) at 110°C for 3h at biomass loadings of 5, 10, 15, 20 and 25wt%. All of the samples were chemically characterized and tested for enzymatic hydrolysis. Physical structures including biomass crystallinity and porosity were measured by X-ray diffraction (XRD) and small angle neutron scattering (SANS), respectively...
February 8, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28213541/accurate-quantification-of-laminarin-in-marine-organic-matter-with-enzymes-from-marine-microbes
#2
Stefan Becker, André Scheffel, Martin F Polz, Jan-Hendrik Hehemann
Marine algae produce varieties of glycans, which fulfill diverse biological functions and fuel the carbon and energy demand of heterotrophic microbes. A common approach to analyze marine organic matter uses acid to hydrolyze its glycans into measurable monosaccharides. These, however, may derive from different glycans that are built with the same monosaccharides, hence this approach does not distinguish between glycans in natural samples. Here we use enzymes to selectively digest and thereby quantify laminarin in particulate organic matter...
February 17, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28213109/screening-of-plants-used-in-the-european-traditional-medicine-to-treat-memory-disorders-for-acetylcholinesterase-inhibitory-activity-and-anti-amyloidogenic-activity
#3
Eva S Lobbens, Karina J Vissing, Lene Jorgensen, Marco van de Weert, Anna K Jäger
ETHNOPHARMACOLOGICAL RELEVANCE: Plants used in the traditional medicine of Europe to treat memory dysfunction and/or to enhance memory were investigated for activity against the underlying mechanisms of Alzheimer's disease. AIM OF THE STUDY: To investigate 35 ethanolic extracts of plants, selected using an ethnopharmacological approach, for anti-amyloidogenic activity as well as an ability to inhibit the enzymatic activity of acetylcholinesterase. MATERIALS AND METHODS: The anti-amyloidogenic activity of the extracts against amyloid beta was investigated by Thioflavin T fibrillation assays and the ability to inhibit the enzymatic activity of acetylcholinesterase was evaluated monitoring the hydrolysis of acetylthiocholine RESULTS: Under the experimental conditions investigated, extracts of two plants, Carum carvi and Olea sylvestris, inhibited amyloid beta fibrillation considerably, eight plant extracts inhibited amyloid beta fibrillation to some extent, 16 plant extracts had no effect on amyloid beta fibrillation and nine extracts accelerated fibrillation of amyloid beta...
February 14, 2017: Journal of Ethnopharmacology
https://www.readbyqxmd.com/read/28212329/enzyme-assisted-discovery-of-antioxidant-peptides-from-edible-marine-invertebrates-a-review
#4
REVIEW
Tsun-Thai Chai, Yew-Chye Law, Fai-Chu Wong, Se-Kwon Kim
Marine invertebrates, such as oysters, mussels, clams, scallop, jellyfishes, squids, prawns, sea cucumbers and sea squirts, are consumed as foods. These edible marine invertebrates are sources of potent bioactive peptides. The last two decades have seen a surge of interest in the discovery of antioxidant peptides from edible marine invertebrates. Enzymatic hydrolysis is an efficient strategy commonly used for releasing antioxidant peptides from food proteins. A growing number of antioxidant peptide sequences have been identified from the enzymatic hydrolysates of edible marine invertebrates...
February 16, 2017: Marine Drugs
https://www.readbyqxmd.com/read/28208065/lignocellulosic-butanol-production-from-napier-grass-using-semi-simultaneous-saccharification-fermentation
#5
Chi-Ruei He, Yu-Yuan Kuo, Si-Yu Li
Napier grass is a potential feedstock for biofuel production because of its strong adaptability and wide availability. Compositional analysis has been done on Napier grass which was collected from a local area of Taiwan. By comparing acid- and alkali-pretreatment, it was found that the alkali-pretreatment process is favorable for Napier grass. An overall glucose yield of 0.82g/g-glucosetotal can be obtained with the combination of alkali-pretreatment (2.5wt% NaOH, 8wt% sample loading, 121°C, and a reaction time of 40min) and enzymatic hydrolysis (40FPU/g-substrate)...
January 30, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28205234/stability-studies-of-potent-opioid-analgesic-morphine-6-o-sulfate-in-various-buffers-and-biological-matrices-by-hplc-dad-analysis
#6
Jai Shankar K Yadlapalli, Zaineb A F Albayati, Narasimha R Penthala, Howard P Hendrickson, Peter A Crooks
The 6-O-sulfate ester of morphine, (M6S), has previously been shown to be an analgesic with greater potency and fewer side effects than to morphine. However, being a sulfate ester derivative of morphine, the question exists as to whether this compound is stable in biological fluids and tissues with regard to pH- and esterase-mediated degradation. To date, no studies have focused on the stability profile of M6S across the physiologically relevant pH range of 1.2 - 7.4. In addition, the stability of M6S is not known in rat plasma and rat brain homogenate, or in simulated rat gastric and intestinal fluids...
February 15, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28203276/a-biorefinery-scheme-to-fractionate-bamboo-into-high-grade-dissolving-pulp-and-ethanol
#7
Zhaoyang Yuan, Yangbing Wen, Nuwan Sella Kapu, Rodger Beatson, D Mark Martinez
BACKGROUND: Bamboo is a highly abundant source of biomass which is underutilized despite having a chemical composition and fiber structure similar as wood. The main challenge for the industrial processing of bamboo is the high level of silica, which forms water-insoluble precipitates negetively affecting the process systems. A cost-competitive and eco-friendly scheme for the production of high-purity dissolving grade pulp from bamboo not only requires a process for silica removal, but also needs to fully utilize all of the materials dissolved in the process which includes lignin, and cellulosic and hemicellulosic sugars as well as the silica...
2017: Biotechnology for Biofuels
https://www.readbyqxmd.com/read/28202667/lrrk2-from-kinase-to-gtpase-to-microtubules-and-back
#8
REVIEW
Marian Blanca Ramírez, Antonio Jesús Lara Ordóñez, Elena Fdez, Sabine Hilfiker
Mutations in the Leucine-Rich Repeat Kinase 2 (LRRK2) gene are intimately linked to both familial and sporadic Parkinson's disease. LRRK2 is a large protein kinase able to bind and hydrolyse GTP. A wealth of in vitro studies have established that the distinct pathogenic LRRK2 mutants differentially affect those enzymatic activities, either causing an increase in kinase activity without altering GTP binding/GTP hydrolysis, or displaying no change in kinase activity but increased GTP binding/decreased GTP hydrolysis...
February 8, 2017: Biochemical Society Transactions
https://www.readbyqxmd.com/read/28202305/enzymatic-synthesis-of-2-o-methylribonucleosides-with-a-nucleoside-hydrolase-family-enzyme-from-lactobacillus-buchneri-lbk78
#9
Yuuki Mitsukawa, Makoto Hibi, Narihiro Matsutani, Nobuyuki Horinouchi, Satomi Takahashi, Jun Ogawa
2'-O-Methylribonucleosides (2'-OMe-NRs) are promising raw materials for the production of nucleic acid drugs. We previously reported that LbNH, a nucleoside hydrolase from Lactobacillus buchneri LBK78 (NITE P-01581), was the first enzyme found to act on 2'-OMe-NRs. In the present study, we determined that LbNH also has the transribosylation activity between 2'-OMe-NRs and nucleobases, in addition to the hydrolyzing activity towards 2'-OMe-NRs. When 2'-O-methyluridine (2'-OMe-UR) and adenine were reacted with LbNH, 2'-O-methyladenosine (2'-OMe-AR) was produced...
February 12, 2017: Journal of Bioscience and Bioengineering
https://www.readbyqxmd.com/read/28202050/cd73-promotes-proliferation-and-migration-of-human-cervical-cancer-cells-independent-of-its-enzyme-activity
#10
Zhao-Wei Gao, Hui-Ping Wang, Fang Lin, Xi Wang, Min Long, Hui-Zhong Zhang, Ke Dong
BACKGROUND: CD73 has both enzymatic and non-enzymatic functions in cells. As a nucleotidase, CD73 plays its enzymatic function by catalyzing the hydrolysis of AMP into adenosine and phosphate. In addition to this, accumulating data have shown that CD73 is a key regulatory molecule involved in cancer growth and metastasis, but this non-enzymatic function of CD73 in cervical cancer cells has not been well studied. METHODS: CD73 was overexpressed by pcDNA-NT5E expression vector transfection in Hela and SiHa cells...
February 15, 2017: BMC Cancer
https://www.readbyqxmd.com/read/28198766/the-differential-effect-of-apyrase-treatment-and-hcd39-overexpression-on-chronic-renal-fibrosis-following-ischemia-reperfusion-injury
#11
Veena Roberts, Duncan J Campbell, Bo Lu, Joanne Chia, Peter J Cowan, Karen M Dwyer
BACKGROUND: Renal ischemia reperfusion injury (IRI) leads to acute kidney injury and renal fibrosis. CD39 is a key purinergic enzyme in the hydrolysis of ATP and increased CD39 enzymatic activity protects from acute IRI but its effect on renal fibrosis is not known. METHODS: Using a mouse model of unilateral renal IRI, the effects of increased CD39 activity (using soluble apyrase and mice expressing human CD39 transgene) on acute and chronic renal outcomes were examined...
February 14, 2017: Transplantation
https://www.readbyqxmd.com/read/28197730/mechanisms-of-the-inhibition-of-enzymatic-hydrolysis-of-waste-pulp-fibers-by-calcium-carbonate-and-the-influence-of-nonionic-surfactant-for-mitigation
#12
Byeong Cheol Min, Bandaru V Ramarao
Recycled paper mills produce large quantities of fibrous rejects and fines which are usually sent to landfills as solid waste. These cellulosic materials can be enzymatically hydrolyzed into sugars for the production of biofuels and biomaterials. Paper mill wastes also contain large amounts of calcium carbonate which inhibits cellulase activity. The calcium carbonate (30%, w/w) decreased 40-60% of sugar yield of unbleached softwood kraft pulp. The prime mechanisms for this are by pH variation, competitive and non-productive binding, and aggregation effect...
February 14, 2017: Bioprocess and Biosystems Engineering
https://www.readbyqxmd.com/read/28197132/combined-carbohydrates-support-rich-communities-of-particle-associated-marine-bacterioplankton
#13
Martin Sperling, Judith Piontek, Anja Engel, Karen H Wiltshire, Jutta Niggemann, Gunnar Gerdts, Antje Wichels
Carbohydrates represent an important fraction of labile and semi-labile marine organic matter that is mainly comprised of exopolymeric substances derived from phytoplankton exudation and decay. This study investigates the composition of total combined carbohydrates (tCCHO; >1 kDa) and the community development of free-living (0.2-3 μm) and particle-associated (PA) (3-10 μm) bacterioplankton during a spring phytoplankton bloom in the southern North Sea. Furthermore, rates were determined for the extracellular enzymatic hydrolysis that catalyzes the initial step in bacterial organic matter remineralization...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28192924/revealing-and-resolving-the-restrained-enzymatic-cleavage-of-dna-self-assembled-monolayers-on-gold-electrochemical-quantitation-and-esi-ms-confirmation
#14
Xiaoyi Gao, Mingxi Geng, Yunchao Li, Xinglin Wang, Hua-Zhong Yu
Herein, we report a combined electrochemical and ESI-MS study of the enzymatic hydrolysis efficiency of DNA self-assembled monolayers (SAMs) on gold, platform systems for understanding nucleic acid surface chemistry, and for constructing DNA-based biosensors. Our electrochemical approach is based on the comparison of the amounts of surface-tethered DNA nucleotides before and after exonuclease I (Exo I) incubation using electrostatically bound [Ru(NH3)6](3+) as redox indicators. It is surprising to reveal that the hydrolysis efficiency of ssDNA SAMs does not depend on the packing density and base sequence, and that the cleavage ends with surface-bound shorter strands (9-13 mers)...
February 9, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28192910/online-monitoring-of-enzymatic-reactions-using-time-resolved-desorption-electrospray-ionization-mass-spectrometry
#15
Si Cheng, Qiuhua Wu, He Xiao, Hao Chen
Electrospray ionization mass spectrometry (ESI-MS) is powerful for determining enzymatic reaction kinetics because of its soft ionization nature. However, it is limited to use ESI-favored solvents containing volatile buffers (e.g., ammonium acetate). In addition, lack of a quenching step for online ESI-MS reaction monitoring might introduce inaccuracy, due to the possible acceleration of reaction in the sprayed microdroplets. To overcome these issues, this study presents a new approach for online measuring enzymatic reaction kinetics using desorption electrospray ionization mass spectrometry (DESI-MS)...
February 9, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28189069/multitarget-sensing-of-glucose-and-cholesterol-based-on-janus-hydrogel-microparticles
#16
Xiao-Ting Sun, Ying Zhang, Dong-Hua Zheng, Shuai Yue, Chun-Guang Yang, Zhang-Run Xu
A visualized sensing method for glucose and cholesterol was developed based on the hemispheres of the same Janus hydrogel microparticles. Single-phase and Janus hydrogel microparticles were both generated using a centrifugal microfluidic chip. For glucose sensing, concanavalin A and fluorescein labeled dextran used for competitive binding assay were encapsulated in alginate microparticles, and the fluorescence of the microparticles was positively correlated with glucose concentration. For cholesterol sensing, the microparticles embedded with γ-Fe2O3 nanoparticles were used as catalyst for the oxidation of 3,3',5,5'-Tetramethylbenzidine by H2O2, an enzymatic hydrolysis product of cholesterol...
February 7, 2017: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/28188936/cultivation-of-podospora-anserina-on-soybean-hulls-results-in-an-efficient-enzyme-cocktail-for-plant-biomass-hydrolysis
#17
Miia R Mäkelä, Ourdia Bouzid, Diogo Robl, Harm Post, Mao Peng, Albert Heck, Maarten Altelaar, Ronald P de Vries
The coprophilic ascomycete fungus Podospora anserina was cultivated on three different plant biomasses, i.e. cotton seed hulls (CSH), soybean hulls (SBH) and acid-pretreated wheat straw (WS) for four days, and the potential of the produced enzyme mixtures was compared in the enzymatic saccharification of the corresponding lignocellulose feedstocks. The enzyme cocktail P. anserina produced after three days of growth on SBH showed superior capacity to release reducing sugars from all tested plant biomass feedstocks compared to the enzyme mixtures from CSH and WS cultures...
February 7, 2017: New Biotechnology
https://www.readbyqxmd.com/read/28188053/exposure-of-portuguese-children-to-the-novel-non-phthalate-plasticizer-di-iso-nonyl-cyclohexane-1-2-dicarboxylate-dinch
#18
Luísa Correia-Sá, André Schütze, Sónia Norberto, Conceição Calhau, Valentina F Domingues, Holger M Koch
Di-(iso-nonyl)-cyclohexane-1,2-dicarboxylate (DINCH) is used as substitute for high molecular weight phthalate plasticizers such as di-(2-ethylhexyl) phthalate (DEHP) and di-(iso-nonyl) phthalate (DINP). Due to a rapid substitution process, we must assume omnipresent and increasing DINCH exposures. The aim of this study was to evaluate DINCH exposure in 112 children (4-18years old) from Portugal, divided in two groups: 1) normal-/underweight following the usual diet; and 2) obese/overweight but under strict nutritional guidance...
February 7, 2017: Environment International
https://www.readbyqxmd.com/read/28181082/growth-and-expression-of-relevant-metabolic-genes-of-clostridium-thermocellum-cultured-on-lignocellulosic-residues
#19
Vanessa O Leitão, Eliane F Noronha, Brenda R Camargo, Pedro R V Hamann, Andrei S Steindorff, Betania F Quirino, Marcelo Valle de Sousa, Cirano J Ulhoa, Carlos R Felix
The plant cell wall is a source of fermentable sugars in second-generation bioethanol production. However, cellulosic biomass hydrolysis remains an obstacle to bioethanol production in an efficient and low-cost process. Clostridium thermocellum has been studied as a model organism able to produce enzymatic blends that efficiently degrade lignocellulosic biomass, and also as a fermentative microorganism in a consolidated process for the conversion of lignocellulose to bioethanol. In this study, a C. thermocellum strain (designated B8) isolated from goat rumen was characterized for its ability to grow on sugarcane straw and cotton waste, and to produce cellulosomes...
February 8, 2017: Journal of Industrial Microbiology & Biotechnology
https://www.readbyqxmd.com/read/28176545/rapid-quantification-of-free-and-glucuronidated-thccooh-in-urine-using-coated-well-plates-and-lc-ms-ms-analysis
#20
Marianne Hädener, Wolfgang Weinmann, Dave R van Staveren, Stefan König
AIM: Generally, urine drug testing for cannabis abuse involves measuring total concentrations of 11-nor-9-carboxy-Δ(9)-tetrahydrocannabinol (THCCOOH) obtained by enzymatic and/or alkaline hydrolysis of THCCOOH-glucuronide. As hydrolysis can be inconsistent and incomplete, direct measurement of the two metabolites is preferable. Methodology & results: We developed a high-throughput LC-MS/MS method for simultaneous quantification of free and glucuronidated THCCOOH in urine using coated 96-well plates for analyte extraction and column-switching chromatography...
February 8, 2017: Bioanalysis
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