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Johanna Méndez Arias Anelize de Oliveira Moraes Luiz Felipe Amarante Modesto Aline Machado de Castro Nei Pereira Jr 《Applied biochemistry and biotechnology》2017,181(2):593-603
Poly(ethylene glycol) (PEG 4000) and bovine serum albumin (BSA) were investigated with the purpose of evaluating their influence on enzymatic hydrolysis of sugarcane bagasse. Effects of these supplements were assayed for different enzymatic cocktails (Trichoderma harzianum and Penicillium funiculosum) that acted on lignocellulosic material submitted to different pretreatment methods with varying solid (25 and 100 g/L) and protein (7.5 and 20 mg/g cellulose) loadings. The highest levels of glucose release were achieved using partially delignified cellulignin as substrate, along with the T. harzianum cocktail: increases of 14 and 18 % for 25 g/L solid loadings and of 33 and 43 % for 100 g/L solid loadings were reached for BSA and PEG supplementation, respectively. Addition of these supplements could maintain hydrolysis yield even for higher solid loadings, but for higher enzymatic cocktail protein loadings, increases in glucose release were not observed. Results indicate that synergism might occur among these additives and cellulase and xylanases. The use of these supplements, besides depending on factors such as pretreatment method of sugarcane bagasse, enzymatic cocktails composition, and solid and protein loadings, may not always lead to positive effects on the hydrolysis of lignocellulosic material, making it necessary further statistical studies, according to process conditions. 相似文献
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Mass spectrometric approaches for the identification of anthracycline analogs produced by actinobacteria
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Anelize Bauermeister Tiago Domingues Zucchi Luiz Alberto Beraldo Moraes 《Journal of mass spectrometry : JMS》2016,51(6):437-445
Anthracyclines are a well‐known chemical class produced by actinobacteria used effectively in cancer treatment; however, these compounds are usually produced in few amounts because of being toxic against their producers. In this work, we successfully explored the mass spectrometry versatility to detect 18 anthracyclines in microbial crude extract. From collision‐induced dissociation and nuclear magnetic resonance spectra, we proposed structures for five new and identified three more anthracyclines already described in the literature, nocardicyclins A and B and nothramicin. One new compound 8 (4‐[4‐(dimethylamino)‐5‐hydroxy‐4,6‐dimethyloxan‐2‐yl]oxy‐2,5,7,12‐tetrahydroxy‐3,10‐dimethoxy‐2‐methyl‐3,4‐dihydrotetracene‐1,6,11‐trione) was isolated and had its structure confirmed by 1H nuclear magnetic resonance. The anthracyclines identified in this work show an interesting aminoglycoside, poorly found in natural products, 3‐methyl‐rhodosamine and derivatives. This fact encouraged to develop a focused method to identify compounds with aminoglycosides (rhodosamine, m/z 158; 3‐methyl‐rhodosamine, m/z 172; 4′‐O‐acethyl‐3‐C‐methyl‐rhodosamine, m/z 214). This method allowed the detection of four more anthracyclines. This focused method can also be applied in the search of these aminoglycosides in other microbial crude extracts. Additionally, it was observed that nocardicyclin A, nothramicin and compound 8 were able to interact to DNA through a DNA‐binding study by mass spectrometry, showing its potential as anticancer drugs. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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So-Yon Lim Adam Bauermeister Richard A Kjonaas Swapan K Ghosh 《Journal of immune based therapies and vaccines》2006,4(1):5-10
Background
Adjuvants are known to significantly enhance vaccine efficacy. However, commercial adjuvants often have limited use because of toxicity in humans. The objective of this study was to determine the comparative effectiveness of a diterpene alcohol, phyto l and its hydrogenated derivative PHIS-01, relative to incomplete Freund's adjuvant (IFA), a commonly used adjuvant in augmenting protective immunity in mice against E. coli and S. aureus, and in terms of inflammatory cytokines. 相似文献8.
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J. Hoffmann B. Hunger D. Dombrowski R. Bauermeister 《Journal of Thermal Analysis and Calorimetry》1990,36(4):1487-1494
The splitting of water in the temperature range from 470 to 970 K was studied for a series of CoNaX zeolites of a Si/Al ratio of 1.18 and of different degree of exchange and at the parent type NaX. In case of CoNaX zeolites peaks at about 570 and 670 K and a broad flat peak at even higher temperatures could be observed. Both the first peaks are ascribed to the process of dehydroxylation between CoOH and structural OH groups, the latter to the dehydroxylation between structural OH groups only. The parent type provided only a single peak with a maximum at about 570 K.From the dehydroxylation peaks activation parameters have been calculated and a scheme has been suggested for the mechanism.
Zusammenfassung Im Temperaturbereich von 470–970 K wurde bei einer Reihe CoNaX Zeolithen mit einem Si/Al-VerhÄltnis von 1.18 und einem unterschiedlichen Austauschgrad sowie bei dem NaX Stammtyp die Abspaltung von Wasser untersucht. Im Falle von CoNaX Zeolithen können Peaks bei 570 und 670 K und ein breiter flacher Peak bei noch höheren Temperaturen beobachtet werden. Die beiden ersten Peaks werden dem Proze\ der Dehydroxylierung zwischen CoOH- und strukturellen OH-Gruppen, letzterer der Dehydroxylierung nur zwischen strukturellen OH-Gruppen zugeschrieben. Der Stammtyp ergibt nur einen einzigen Peak mit einem Maximum bei 570 K. Aus den Dehydroxylierungspeaks wurden Aktivierungsparameter berechnet und ein Mechanismusschema entwickelt.相似文献
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Six O, O-diethyl-N-acylphosphoramidates ( 1a-f ) were synthesized. The reactions of their conjugate bases with haloalkanes were studied. The N/(phosphoryl)O/(carbonyl)O regioselectivity varied greatly, depending on the substrate, the haloalkane, the base, and other reaction conditions. The earlier [17] reaction of N-formyl substrate 1a that led to the N-phosphorylated formamidine was extended to other substrates 1 . Again, the yields and the selectivity depended strongly on the structure of a substrate. 相似文献