The industrial production of short-chain fructooligosaccharides (FOS) and inulooligosaccharides is expanding rapidly due to the pharmaceutical importance of these compounds. These compounds, ...concisely termed prebiotics, have biofunctional properties and hence health benefits if consumed in recommended dosages. Prebiotics can be produced enzymatically from sucrose elongation or via enzymatic hydrolysis of inulin by exoinulinases and endoinulinases acting alone or synergistically. Exoinulinases cleave the non-reducing β-(2, 1) end of inulin-releasing fructose while endoinulinases act on the internal linkages randomly to release inulotrioses (F3), inulotetraoses (F4) and inulopentaoses (F5) as major products. Fructosyltransferases act by cleaving a sucrose molecule and then transferring the liberated fructose molecule to an acceptor molecule such as sucrose or another oligosaccharide to elongate the short-chain fructooligosaccharide. The FOS produced by the action of fructosyltransferases are 1-kestose (GF2), nystose (GF3) and fructofuranosyl nystose (GF4). The production of high yields of oligosaccharides of specific chain length from simple raw materials such as inulin and sucrose is a technical challenge. This paper critically explores recent research trends in the production and application of short-chain oligosaccharides. Inulin and enzyme sources for the production of prebiotics are discussed. The mechanism of FOS chain elongation and also the health benefits associated with prebiotics consumption are discussed in detail.
Biosorption has emerged as a low-cost and often low-tech option for removal or recovery of base metals from aqueous wastes. The conditions under which precious metals such as gold, platinum and ...palladium are sorbed by biomass are often very different to those under which base metals are sorbed. This, coupled with the increasingly high demand for precious metals, drives the increase in research into efficient recovery of precious metal ions from all waste material, especially refining wastewaters. Common biosorbents for precious metal ions include various derivatives of chitosan, as well as other compounds with relatively high surface amine functional group content. This is generally due to the ability of the positively charged amine groups to attract anionic precious metal ions at low pH. Recent research regarding the biosorption of some precious metals is reviewed here, with emphasis on the effects of the biosorption environment and the biosorption mechanisms identified.
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•Pregnancy-induced rise in fecal progesterone metabolites was detected only by EIA.•11-deoxycortisol was the main fecal glucocorticoid detected by UPC2-MS/MS.•Fecal ...11-ketoandrostenedione was detected by UPC2-MS/MS in males and females.•Bacteroidia was the most abundant fecal microbe class in both sexes.•Spirochaetia abundance was decreased in response to immobilization in a male.
Increased poaching in northern South Africa has necessitated relocation of large numbers of southern white rhinoceros (Ceratotherium simum simum) to the Eastern Cape Province. The climate and grassland ecology of this province differ from that of northern South Africa which may impact the health of this species. This assessment of fecal steroid levels and microbiome in 10 free-ranging southern white rhinoceros in the Eastern Cape will provide insights into white rhinoceros physiology in this biome. Fecal steroid metabolites were analyzed using enzyme immunoassay (EIA) and ultra-performance convergence chromatography tandem mass spectrometry (UPC2-MS/MS). Fecal microbial composition was assessed via next generation sequencing. EIAs with antibodies raised against progesterone (P4; mouse monoclonal – CL425 clone), testosterone (T; rabbit polyclonal), corticosterone (B; sheep polyclonal) were utilized. Pregnant females had large quantities of fecal progesterone metabolites (FPMs) detected by CL425 EIA. Pregnant females also had native P4 and 11α-hydroxydihydroprogesterone (11αOHDHP4; 4-pregnen-11α-ol-3,20-dione) detected by UPC2-MS/MS but these concentrations were 1000-fold less than the concentrations of FPMs detected by the CL425 EIA. By contrast, non-pregnant females had FPM concentrations detected by CL425 EIA which were similar to native P4 and 11αOHDHP4 concentrations detected by UPC2-MS/MS. Mean fecal androgen metabolite (FAM) concentrations detected by the T EIA were similar between males and females. 11-ketoandrostenedione (11KA4) detected by UPC2-MS/MS was higher in females than males. However, there was no difference between males and females in the concentration of fecal glucocorticoid metabolites (FGMs) detected by the B EIA. Bacteroidia, followed by Clostridia, was the most abundant classes of fecal microbes. The unfiltered microbiome of females was more diverse than that of males. The core fecal microbiome of young rhinoceros had a higher observed species richness (Shannon diversity index, and Simpson diversity index) than that of old rhinoceros. In the alpha male, immobilization was associated with an increase in FGMs detected by 11-deoxycortisol (S) detected by UPC2-MS/MS coupled with decreased abundance of Spirochaetia. We detected substantially different FAM and FPM concentrations from those previously reported for both captive and wild white rhinoceros. Comparison of our UPC2-MS/MS and EIA results underscores the fact that most EIAs are highly cross reactive for many steroid metabolites. Our data also demonstrates a distinct effect of stress not only on FGMs but also on the fecal microbiome. This is the first non-invasive assessment of fecal steroid metabolites by UPC2-MS/MS and the fecal microbiome in wild white rhinoceros.
A transferase was isolated, purified and characterised from
Aspergillus aculeatus. The enzyme exhibited a pH and temperature optima of 6.0 and 60
°C, respectively and under such conditions remained ...stable with no decrease in activity after 5
h. The enzyme was purified 7.1 fold with a yield of 22.3% and specific activity of 486.1
U
mg
−1 after dialysis, concentration with polyethyleneglycol (30%) and DEAE-Sephacel chromatography. It was monomeric with a molecular mass of 85
kDa and K
m and V
max values of 272.3
mM and 166.7
μmol
min
−1
ml
−1. The influence of pH, temperature, reaction time, and enzyme and sucrose concentration on the formation of short-chain fructooligosaccharides (FOS) was examined by statistical response surface methodology (RSM). The enzyme showed both transfructosylation and hydrolytic activity with the transfructosylation ratio increasing to 88% at a sucrose concentration of 600
mg
ml
−1. Sucrose concentration (400
mg
ml
−1) temperature (60
°C), and pH (5.6) favoured the synthesis of high levels of GF
3 and GF
4. Incubation time had a critical effect on the yield of FOS as the major products were GF
2 after 4
h and GF
4 after 8
h. A prolonged incubation of 16
h resulted in the conversion of GF
4 into GF
2 as a result of self hydrolase activity.
ZusammenfassungHintergrundInterdisziplinäre Fallkonferenzen sind im onkologischen Bereich fest etabliert, um Patienten:innen mit komplexen Krankheitsbildern, die mehrere Fachgebiete überschneiden, ...die bestmögliche Therapie anzubieten.MethodenIn einem interdisziplinären Kollegengespräch wurden nach Studium vorliegender Literatur Ziele, Indikationen, Frequenz, Anmelde- und Dokumentationsmodalitäten, erforderliche Fachdisziplinen zur Erstellung des rekonstruktiven Plans sowie Evaluationsparameter des Boards und der Behandlung konsentiert. Die Nutzung des Extremitäten-Boards und demografischen Merkmale der innerhalb der ersten 6 Monate im Extremitäten-Board vorgestellten Patienten:innen wurden anschließend deskriptiv analysiert.ErgebnisseDas konsentierte primäre Ziel des Extremitäten-Boards ist die hochqualitative, transparente und frühzeitige Erstellung eines ganzheitlichen rekonstruktiven Plans zur optimierten Behandlung eines herausfordernden Kollektivs aus Patienten:innen mit Komplexverletzungen. Entscheidende Schnittstellen eines Extremitäten-Boards sind die Partizipation der interdisziplinären Disziplinen, etablierte Anmelde- und Dokumentationsmodalität sowie eine longitudinale Analyse von Parametern der medizinischen Akutversorgung, der langfristigen Funktion und Lebensqualität der Betroffenen. Das bisherige Patientenkollektiv umfasst v. a. unter 40-jährige Männer mit Weichteildefekten und kombinierten Verletzungen. Durchschnittlich wurden pro Sitzungstermin Rekonstruktionspläne für einen bis 2 Patienten:innen im interdisziplinären Team konsentiert.SchlussfolgerungenDas Extremitäten-Board wird für die Planung der Behandlung von Komplexverletzungen angenommen. Personeller und zeitlicher Aufwand stellen die größten Herausforderungen bei der erfolgreichen Umsetzung dar. Das Extremitäten-Board ermöglicht ein hohes Maß an interdisziplinärer Vernetzung. Die digitale Anmelde- und Dokumentationsmodalität innerhalb des krankenhausinternen Dokumentationssystems ist von größter Relevanz. Die Erstellung des rekonstruktiven Plans ist von entscheidender Bedeutung für den qualitativen Erfolg der Behandlung und die Funktionswiederherstellung. Um die Versorgungsqualität zu messen, ist die longitudinale Analyse geeigneter Parameter zwingend notwendig.
Oligosaccharides of chain length up to degree of polymerisation (DP) 5 have been synthesised using a purified endoinulinase and response surface methodology with central composite experimental design ...for the optimisation of the product yield. The endoinulinase was purified through a three-step procedure in a yield of 1.11% and 3.5-fold and its molecular weight was 68.1
kDa by SDS-PAGE. It had optimum pH and temperature values of 6 and 60
°C, respectively with only 10% loss in activity over 60
min under these conditions. From the kinetic studies
K
m and
V
max were estimated at 3.53
mM and 666.7
μmol
min
−1
ml
−1, respectively. Using the purified endoinulinase preparation isolated from
Aspergillus niger, at a temperature (60
°C), inulin concentration (150
mg
ml
−1), incubation time (48
h), pH (6.0) and enzyme dosage (60
U
ml
−1) produced high yields of inulotrioses (70.3
mM), inulotetraoses (38.8
mM), and inulopentaoses (3.5
mM). Response surface regression predicted similar product levels under the same conditions. A comparative analysis of the yields of individual oligosaccharides produced from both the crude and purified enzyme is also presented.
Recombinant triosephosphate isomerase from Plasmodium falciparum (PfTIM) and humans (hTIM) were expressed, purified and characterised. High specific activity (1207 U x mg(-1)) with a fold ...purification of -1.8 and a yield of 48% were obtained for hTIM after gel filtration while, in contrast PfTIM afforded a specific activity of 1387 U x mg(-1) with a fold purification of -6.8 and a yield of 57% after gel filtration and prior to dialysis. PfTIM had an optimal pH and temperature, K(m) and V(max) of 5.25, 25 degrees C, 12.8 mM and 1.13 μmol x mL(-1) min(-1) respectively while for hTIM the pH and temperature optima, K(m) and V(max) were 6.75, 30 degrees C; 8.2 mM and 1.35 μmol x ml(-1) min(-1). Polyvinylpyrrolidone stabilised silver nanoparticles (60 nM; 2-6 nm diameter) selectively inhibited PfTIM with a 7-fold decrease in enzyme catalytic efficiency (K(cat)/K(m)) over hTIM. Respective K(i) values were 283 nM hTIM and 85.7 nM PfTIM. Key structural differences between the two enzyme variants, especially with Cys13 at the dimer interface of PfTIM, were significant enough to suggest unique characteristics allowing for selective targeting of PfTIM by AgNPs.
Interdisciplinary case conferences are well-established in the field of oncology in order to provide the best possible treatment for patients with complex disease patterns which overlap several ...disciplines.
After studying the available literature the aims, indications, frequency, patient enrolment and documentation modalities, disciplines necessary to create the reconstruction plan and evaluation parameters of the board, were agreed in an interdisciplinary discussion among colleagues. The utilization of the extremity board and demographic features of the cases presented in the extremity board within the first 6 months were subsequently descriptively analyzed.
The agreed primary aim of an extremity board is the timely and transparent preparation of a high-quality holistic reconstruction plan for optimized treatment of a challenging patient collective with complex injuries of the extremities. Decisive interfaces of an extremity board are the participation of interdisciplinary disciplines, established enrolment and documentation modalities and a longitudinal analysis of parameters of the acute medical treatment, the long-term function and quality of life of those affected. The patient collective so far mostly includes men under 40 years old with traumatic soft tissue defects and combined injuries. On average, reconstruction plans for 1-2 patients were approved in an interdisciplinary team per session.
The extremity board serves as a platform for coordinated planning of treatment for patients with complex injuries. The limited personnel and time resources represent the greatest challenge for the successful implementation. The extremity board enables a high degree of interdisciplinary networking. The digital registration and documentation modality within the internal hospital documentation system is of utmost relevance. The preparation of the reconstruction plan is of decisive importance for the qualitative success of treatment and the restoration of function. The longitudinal analysis of appropriate parameters is imperative to measure the quality of treatment.
•Recombinant His-tagged thiazole kinase isolated, purified from genomic DNA of Plasmodium falciparum.•Monomeric enzyme with mass 34kDa, specific activity 295nmolmg−1 temperature and pH optima of 37°C ...and 7.5.•Km (65μM) and Vmax (36.8μmolml−1min−1) purified by FPLC on Sephacryl S100HR.•Non-competitive inhibition by Ag (79%; Ki=6.45μM).•Nanoparticles interact through Met1, Cys206 on surface of enzyme.
Malaria, a mosquito-borne infectious disease, is caused by the Plasmodium genus, and remains one of the greatest health challenges worldwide. The malarial parasite possess a biosynthetic pathway for the B-group vitamin incorporating the thiamine metabolizing enzymes; humans on the other hand cannot synthesize the vitamin and require it from within their diet. The vitamin B1 biosynthetic enzyme 5-(2-hydroxyethyl)-4-methylthioazolekinase EC. 2.7.1.50 from Plasmodium (PfThzK) is particularly attractive as a biomedical target since any inhibition of this enzyme may lead to an effective treatment for malaria. In the present study, PfThzK was recombinantly produced as a 6× His fusion protein in Escherichia coli BL21(DE3) and purified using nickel affinity and size exclusion chromatography. The enzyme was monomeric with a molecular mass of 34kDa, a specific activity of 295.04nmolmin−1mg−1 and showed an optimum temperature and pH of 37°C and 7.5, respectively. The purified PfThzK was non-competitively inhibited (79%) by silver nanoparticles (2–6nm); Ki=6.45μM. A mechanism is suggested for the interaction of the silver nanoparticle with PfThzK through two sulphur bearing amino acids (Met1, Cys206) on the surface of each subunit of the enzyme.
Gasification of renewable fuels is not common practice due to the high costs of technologies and the absence of reliably working refractories. Refractory degradation is of such high significance that ...improved refractory durability was ranked first by industry experts in a list of 20 research and development areas related to the economic viability of gasification. Therefore, for improvement of the reliability and durability of refractory linings, this work is dealing with the corrosion resistance of nine commercial refractories to a variety of emissions from potential fuels. The refractories were exposed to a gasifier-like, water vapour and alkali rich atmosphere. Exposures with a duration of 250 h produced corrosion effects that were investigated by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction. Furthermore, thermodynamic calculations were included to further explain the equilibrium chemistry. The results show that extremely low silica refractories are promising candidates for gasifier utilisation.
