scholarly journals High Enzymatic Recovery and Purification of Xylooligosaccharides from Empty Fruit Bunch via Nanofiltration

Processes ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 619
Author(s):  
Hans Wijaya ◽  
Kengo Sasaki ◽  
Prihardi Kahar ◽  
Nanik Rahmani ◽  
Euis Hermiati ◽  
...  
Keyword(s):  
Membrane Separation ◽  
Specific Activity ◽  
High Yield ◽  
Dual Function ◽  
Empty Fruit Bunch ◽  
Alkali Pretreatment ◽  
Nanofiltration Membranes ◽  
Degree Of Separation ◽  
Main Component ◽  
High Degree

Xylooligosaccharides (XOS) are attracting an ever-increasing amount of interest for use as food prebiotics. In this study, we used efficient membrane separation technology to convert lignocellulosic materials into a renewable source of XOS. This study revealed a dual function of nanofiltration membranes by first achieving a high yield of xylobiose (a main component of XOS) from alkali-pretreated empty fruit bunch (EFB) hydrolysate, and then by achieving a high degree of separation for xylose as a monosaccharide product. Alkali pretreatment could increase the xylan content retention of raw EFB from 23.4% to 26.9%, which eventually contributed to higher yields of both xylobiose and xylose. Nanofiltration increased the total amount of XYN10Ks_480 endoxylanase produced from recombinant Streptomyces lividans 1326 without altering its specific activity. Concentrated XYN10Ks_480 endoxylanase was applied to the recovery of both xylobiose and xylose from alkali-pretreated EFB hydrolysate. Xylobiose and xylose yields reached 41.1% and 17.3%, respectively, and when unconcentrated XYN10Ks_480 endoxylanase was applied, those yields reached 35.1% and 8.3%, respectively. The last step in nanofiltration was to separate xylobiose over xylose, and 41.3 g.L−1 xylobiose (90.1% purity over xylose) was achieved. This nanofiltration method should shorten the processes used to obtain XOS as a high-value end product from lignocellulosic biomass.

scholarly journals Optimal Design of a Hydrolysis Sugar Membrane Purification System Using a Superstructure-Based Approach

Processes ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 168
Author(s):  
Chien-Yuan Su ◽  
Bo-Yan Ji ◽  
Pei-Jung Yu ◽  
Ming-Hua Wang ◽  
Wei-Chun Hung ◽  
...  
Keyword(s):  
Membrane Separation ◽  
High Yield ◽  
Separation System ◽  
Nanofiltration Membranes ◽  
Membrane Unit ◽  
Membrane Performance ◽  
Proposed Model ◽  
Purification System ◽  
Membrane Type ◽  
Membrane Networks

As an alternative to gasoline, bioethanol can be produced from lignocellulosic biomass through hydrolysis using an ionic solution containing zinc chloride (ZnCl2). This method allows for a high yield of glucose from lignocellulose, but entails the removal of ZnCl2 from the hydrolysate using multiple nanofiltration membranes before the fermentation of glucose. This paper presents a mathematical technique for designing such a multistage membrane separation system. The optimization model for the synthesis of membrane networks is based on a superstructure with all feasible interconnections between the membrane units, and consists of mass balances, logical constraints and product specifications. A case study of the separation of a bagasse hydrolysis solution is used to demonstrate the application of the proposed model. Results show that using both types of nanofiltration membranes allows higher ZnCl2 removal ratios at each membrane unit, hence a decrease in the number of membrane units required and a reduction of about 35% in capital cost compared to the cases in which only one membrane type is used. Further analysis is performed to examine the effect of membrane performance on the economics of the separation system.

scholarly journals Whole cell-based catalyst for enzymatic production of the osmolyte 2-O-α-glucosylglycerol

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Katharina N. Schwaiger ◽  
Monika Cserjan-Puschmann ◽  
Gerald Striedner ◽  
Bernd Nidetzky
Keyword(s):  
Specific Activity ◽  
Dry Mass ◽  
High Yield ◽  
Sucrose Phosphorylase ◽  
Bifidobacterium Adolescentis ◽  
Enzymatic Production ◽  
Intracellular Enzyme ◽  
Whole Cell ◽  
Freeze Thaw ◽  
Thaw Cycle

Abstract Background Glucosylglycerol (2-O-α-d-glucosyl-sn-glycerol; GG) is a natural osmolyte from bacteria and plants. It has promising applications as cosmetic and food-and-feed ingredient. Due to its natural scarcity, GG must be prepared through dedicated synthesis, and an industrial bioprocess for GG production has been implemented. This process uses sucrose phosphorylase (SucP)-catalyzed glycosylation of glycerol from sucrose, applying the isolated enzyme in immobilized form. A whole cell-based enzyme formulation might constitute an advanced catalyst for GG production. Here, recombinant production in Escherichia coli BL21(DE3) was compared systematically for the SucPs from Leuconostoc mesenteroides (LmSucP) and Bifidobacterium adolescentis (BaSucP) with the purpose of whole cell catalyst development. Results Expression from pQE30 and pET21 plasmids in E. coli BL21(DE3) gave recombinant protein at 40–50% share of total intracellular protein, with the monomeric LmSucP mostly soluble (≥ 80%) and the homodimeric BaSucP more prominently insoluble (~ 40%). The cell lysate specific activity of LmSucP was 2.8-fold (pET21; 70 ± 24 U/mg; N = 5) and 1.4-fold (pQE30; 54 ± 9 U/mg, N = 5) higher than that of BaSucP. Synthesis reactions revealed LmSucP was more regio-selective for glycerol glycosylation (~ 88%; position O2 compared to O1) than BaSucP (~ 66%), thus identifying LmSucP as the enzyme of choice for GG production. Fed-batch bioreactor cultivations at controlled low specific growth rate (µ = 0.05 h−1; 28 °C) for LmSucP production (pET21) yielded ~ 40 g cell dry mass (CDM)/L with an activity of 2.0 × 104 U/g CDM, corresponding to 39 U/mg protein. The same production from the pQE30 plasmid gave a lower yield of 6.5 × 103 U/g CDM, equivalent to 13 U/mg. A single freeze–thaw cycle exposed ~ 70% of the intracellular enzyme activity for GG production (~ 65 g/L, ~ 90% yield from sucrose), without releasing it from the cells during the reaction. Conclusions Compared to BaSucP, LmSucP is preferred for regio-selective GG production. Expression from pET21 and pQE30 plasmids enables high-yield bioreactor production of the enzyme as a whole cell catalyst. The freeze–thaw treated cells represent a highly active, solid formulation of the LmSucP for practical synthesis.

Synthesis and N.M.R. Spectra of Substituted Aminoiodoacridines

1979 ◽  
Vol 32 (12) ◽  
pp. 2637 ◽  
Author(s):  
RF Martin ◽  
DP Kelly
Keyword(s):  
Electron Density ◽  
Electrophilic Substitution ◽  
Specific Activity ◽  
Diazonium Salt ◽  
High Specific Activity ◽  
High Yield ◽  
Model Compounds ◽  
Iodide Ion ◽  
Ion Substitution ◽  
Chloramine T

3-Amino-6-iodoacridine (10), 3,6-diiodoacridine (11) and 9-amino-2-ethoxy-6-iodoacridine (14) were prepared by iodide ion substitution of the corresponding diazonium salt whereas 3,6-diamino-4,5-diiodoacridine (12) and 6,9-diamino-2-ethoxy-5-iodoacridine (13) were prepared by direct iodination with iodide ion in the presence of chloramine-T. The latter reaction proceeded in relatively high yield and has been used for the synthesis of high specific activity 125I-labelled compounds (12), (13). The 1H and 13C N.M.R. spectra of (10)-(14) and model compounds indicate higher electron density at C4(C5) than at C2(C7) in 3(6)-amino-substituted acridines in agreement with the observed pattern of electrophilic substitution.

scholarly journals A Novel Purification Procedure for Active Recombinant Human DPP4 and the Inability of DPP4 to Bind SARS-CoV-2

2020 ◽  
Author(s):  
Cecy Xi ◽  
Arianna Arianna Di Fazio ◽  
Naveed Nadvi ◽  
Karishma Patel ◽  
Michelle Xiang ◽  
...  
Keyword(s):  
Affinity Chromatography ◽  
High Purity ◽  
Specific Activity ◽  
Specific Binding ◽  
Exchange Chromatography ◽  
Cell Surface Receptor ◽  
Spike Protein ◽  
High Yield ◽  
Purification Procedure ◽  
Dipeptidyl Peptidase 4

Proteases catalyse irreversible posttranslational modifications that often alter a biological function of the substrate. The protease dipeptidyl peptidase 4 (DPP4) is a pharmacological target in type 2 diabetes therapy primarily because it inactivates glucagon-like protein-1. DPP4 also has roles in steatosis, insulin resistance, cancers and inflammatory and fibrotic diseases. In addition, DPP4 binds to the spike protein of MERS virus, causing it to be the human cell surface receptor for that virus. DPP4 has been identified as a potential binding target of SARS-CoV-2 spike protein, so this question requires experimental investigation. Understanding protein structure and function requires reliable protocols for production and purification. We developed such strategies for baculovirus generated soluble recombinant human DPP4 (residues 29-766) produced in insect cells. Purification used differential ammonium sulfate precipitation, hydrophobic interaction chromatography, dye affinity chromatography in series with immobilised metal affinity chromatography, and ion exchange chromatography. The binding affinities of DPP4 to the SARS-CoV-2 full-length spike protein and its receptor binding domain (RBD) were measured using surface plasmon resonance. This optimised DPP4 purification procedure yielded 1 to 1.8 mg of pure fully active soluble DPP4 protein per litre of insect cell culture with specific activity >30 U/mg, indicative of high purity. No specific binding between DPP4 and CoV-2 spike protein was detected. In summary, a procedure for high purity high yield soluble human DPP4 was achieved and used to show that, unlike MERS, SARS-CoV-2 does not bind human DPP4.

scholarly journals Characterization of Multiple forms of Human Thrombin

1977 ◽  
Author(s):  
J.J. Gorman ◽  
P.A. Castaldi
Keyword(s):  
Specific Activity ◽  
Peptide Mapping ◽  
Multiple Forms ◽  
Bovine Thrombin ◽  
Molecular Weights ◽  
Human Thrombin ◽  
Affinity Resin ◽  
C 50 ◽  
High Degree

Human thrombin was obtained by activation of partially purified human prothrombin with venom of the Australian Taipan (oxyuranus scutellatus scutellatus).The crude thrombin was precipitated with ammonium sulphate and subsequently purified by chromatography on Sephadex G-75 CM-Sephadex C-50 and the affinity resin am inobenzamidine-CH-Sepharose. The final preparation had a specific activity of 1700 units per absorbance unit (A| cm 280n m Was herterogenous as shown by urea-acrylamide gel electrophoresis at acid pH and by isoelectric focusing. SDS-acrylamide electrophoresis revealed molecular weights of 39,000, 28,000, 25-23,000 and 15-12,000 for these proteins. The 39,000 dalton species predominated (greater than 90%) when the enzyme was inhibited with phenyImethanesuI phony I fluoride prior to dialysis against 0.02M sod i urn phosphate (pH 8.0) containing 0.1% SDS. Lack of such inhibition reduced the amount of the 39,000 dalton species to less than 60% with concomitant increase in the smaller species. Increase in the smaller species also occurred during incubation in 0.IM NaCI-0.I M Tris buffer (pH 8.0).Peptide mapping studies indicated that the smaller species were structurally related to the 39,000 dalton species. Amino acid compositions of tryptic peptides indicated a high degree of homology with bovine thrombin.It has been established that human thrombin can exist in at least two secondary structural forms of different molecular weights, probably due to autolytic degradation of the largest (39,000 dalton) protein species.

Preparation of 14C-Labeled Penicillic Acid with High Specific Activity and Yield

1977 ◽  
Vol 40 (2) ◽  
pp. 90-93 ◽  
Author(s):  
DOUGLAS L. PARK ◽  
PHILIP B. MISLIVEC ◽  
JAMES L. HEATH
Keyword(s):  
Acid Production ◽  
Specific Activity ◽  
High Specific Activity ◽  
High Yield ◽  
Liquid Media ◽  
Penicillic Acid ◽  
Stationary Culture ◽  
Radioactive Compound ◽  
Growth Substrates ◽  
Label Incorporation

14C-Labeled penicillic acid was produced by stationary culture incubation of Penicillium cyclopium (NRRL 1888) on a modified Raulin-Thom broth medium containing 14C-labeled acetate. Approximately 1.2 g of radioactive compound, with a specific activity of 23.0 μCi/mmole, was produced in 9 days in 1500 ml of the broth. Incorporation of the isotope into penicillic acid was 11. 9%. Production of the radiolabeled compound with high specific activity was achieved by correlating the monitoring of expired 14C-CO2 with production of penicillic acid during the fermentation. The effects of various growth substrates, pH, and incubation times on production of non-labeled penicillic acid also were investigated. Results show that sterile rice is an excellent substrate, that among liquid media examined, higher yields were obtained in stationary rather than in shake cultures, and that higher yields of penicillic acid were obtained at pH 3.5 or lower. Simultaneous monitoring of penicillic acid production and 14C-label incorporation is essential to detect and isolate a high yield of labeled compound with high specific activity.

scholarly journals 188W/188Re Generator System and Its Therapeutic Applications

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
A. Boschi ◽  
L. Uccelli ◽  
M. Pasquali ◽  
A. Duatti ◽  
A. Taibi ◽  
...  
Keyword(s):  
Specific Activity ◽  
Maximum Energy ◽  
Beta Particle ◽  
High Yield ◽  
Generator System ◽  
Therapeutic Applications ◽  
Radioactive Concentration ◽  
Decay Pattern ◽  
Chemical Strategies ◽  
Very High

The188Re radioisotope represents a useful radioisotope for the preparation of radiopharmaceuticals for therapeutic applications, particularly because of its favorable nuclear properties. The nuclide decay pattern is through the emission of a principle beta particle having 2.12 MeV maximum energy, which is enough to penetrate and destroy abnormal tissues, and principle gamma rays (Eγ=155 keV), which can efficiently be used for imaging and calculations of radiation dose.188Re may be conveniently produced by188W/188Re generator systems. The challenges related to the double neutron capture reaction route to provide only modest yield of the parent188W radionuclide indeed have been one of the major issues about the use of188Re in nuclear medicine. Since the specific activity of188W used in the generator is relatively low (<185 GBq/g), the elutedRe188O4-can have a low radioactive concentration, often ineffective for radiopharmaceutical preparation. However, several efficient postelution concentration techniques have been developed, which yield clinically usefulRe188O4-solutions. This review summarizes the technologies developed for the preparation of188W/188Re generators, postelution concentration of the188Re perrhenate eluate, and a brief discussion of new chemical strategies available for the very high yield preparation of188Re radiopharmaceuticals.

scholarly journals A New Procedure for Purification of Crotalase From Crotalus Adamanteus Venom

1977 ◽  
Author(s):  
F.S. Markland ◽  
J. Chou ◽  
Y. Shih ◽  
H. Pirkle
Keyword(s):  
Sodium Chloride ◽  
Large Scale ◽  
Specific Activity ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Fold Increase ◽  
Tris Buffer ◽  
High Yield ◽  
Crude Venom ◽  
Diamondback Rattlesnake

A new procedure has been developed for large scale, rapid purification of crotalase, the thrombin-1ike enzyme from the venom of the eastern diamondback rattlesnake (Crotalus adamanteus). The three step procedure involves: (1) molecular sieve chromatography on Sephadex G-100 in 0.04 M Tris buffer containing 0.10 M sodium chloride, pH 7.1; (2) gradient elution from DEAE-cellulose with sodium acetate buffer, pH 7.0; and (3) affinity chromatography on p-aminobenzamidine Sepharose using a spacer of 6-aminohexanoic acid. Crotalase was eluted from the affinity resin by 0.05 M Tris buffer containing 0.10 M sodium chloride and 0.15 M benzamidine-hydrochloride, pH 9.0, after first washing with the Tris buffer containing 0.40 M sodium chloride. From the crude venom, pure enzyme was obtained with an overall recovery of 40-60% of clotting activity and a 90-100 fold increase in specific activity. Crotalase was shown to be pure by Polyacrylamide disk gel electrophoresis which gave one band. The molecular weight was estimated to be approximately 31,000 by gel filtration on a calibrated Sephadex G-100 column. Amino acid analysis was performed and the composition was shown to be very similar to that reported earlier (F.S. Markland and P.S. Damus, J. Biol. Chem. 246: 6460, 1971). Clotting activity of the enzyme was not inhibited by heparin, either with or without plasma, whereas, thrombin was rapidly inactivated by heparin in the presence of plasma. In conclusion, we have developed a rapid and reproducible procedure for isolation in high yield of large quantities of the thrombin-like enzyme from the venom of the eastern diamondback rattlesnake. Studies are continuing on the primary structure and possible clinical applications of this enzyme.

High yield of second-generation ethanol in an ionic Liquid-Cellulase integrated system for single-step processing of empty fruit bunch

Biofuels ◽  
2019 ◽  
pp. 1-12 ◽  
Author(s):  
Amal A.M. Elgharbawy ◽  
MD. Zahangir Alam ◽  
Muhammad Moniruzzaman ◽  
Nassereldeen Ahmad Kabbashi ◽  
Parveen Jamal
Keyword(s):  
Ionic Liquid ◽  
Second Generation ◽  
Single Step ◽  
Integrated System ◽  
High Yield ◽  
Empty Fruit Bunch ◽  
Second Generation Ethanol

scholarly journals A Novel Purification Procedure for Active Recombinant Human DPP4 and the Inability of DPP4 to Bind SARS-CoV-2

Molecules ◽  
2020 ◽  
Vol 25 (22) ◽  
pp. 5392
Author(s):  
Cecy R Xi ◽  
Arianna Di Fazio ◽  
Naveed Ahmed Nadvi ◽  
Karishma Patel ◽  
Michelle Sui Wen Xiang ◽  
...  
Keyword(s):  
Surface Plasmon Resonance ◽  
Affinity Chromatography ◽  
Surface Plasmon ◽  
Plasmon Resonance ◽  
High Purity ◽  
Specific Activity ◽  
Cell Surface Receptor ◽  
Spike Protein ◽  
High Yield ◽  
Purification Procedure

Proteases catalyse irreversible posttranslational modifications that often alter a biological function of the substrate. The protease dipeptidyl peptidase 4 (DPP4) is a pharmacological target in type 2 diabetes therapy primarily because it inactivates glucagon-like protein-1. DPP4 also has roles in steatosis, insulin resistance, cancers and inflammatory and fibrotic diseases. In addition, DPP4 binds to the spike protein of the MERS virus, causing it to be the human cell surface receptor for that virus. DPP4 has been identified as a potential binding target of SARS-CoV-2 spike protein, so this question requires experimental investigation. Understanding protein structure and function requires reliable protocols for production and purification. We developed such strategies for baculovirus generated soluble recombinant human DPP4 (residues 29–766) produced in insect cells. Purification used differential ammonium sulphate precipitation, hydrophobic interaction chromatography, dye affinity chromatography in series with immobilised metal affinity chromatography, and ion-exchange chromatography. The binding affinities of DPP4 to the SARS-CoV-2 full-length spike protein and its receptor-binding domain (RBD) were measured using surface plasmon resonance and ELISA. This optimised DPP4 purification procedure yielded 1 to 1.8 mg of pure fully active soluble DPP4 protein per litre of insect cell culture with specific activity >30 U/mg, indicative of high purity. No specific binding between DPP4 and CoV-2 spike protein was detected by surface plasmon resonance or ELISA. In summary, a procedure for high purity high yield soluble human DPP4 was achieved and used to show that, unlike MERS, SARS-CoV-2 does not bind human DPP4.

Sign in / Sign up

Export Citation Format

Share Document