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1.
Biotechnol Bioeng ; 116(11): 2874-2883, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31286482

RESUMO

Compact 1 H NMR and Raman spectrometers were used for real-time process monitoring of alcoholic fermentation in a continuous flow reactor. Yeast cells catalyzing the sucrose conversion were immobilized in alginate beads floating in the reactor. The spectrometers proved to be robust and could be easily attached to the reaction apparatus. As environmentally friendly analysis methods, 1 H NMR and Raman spectroscopy were selected to match the resource- and energy-saving process. Analyses took only a few seconds to minutes compared to chromatographic procedures and were, therefore, suitable for real-time control realized as a feedback loop. Both compact spectrometers were successfully implemented online. Raman spectroscopy allowed for faster spectral acquisition and higher quantitative precision, NMR yielded more resolved signals thus higher specificity. By using the software Matlab for automated data loading and processing, relevant parameters such as the ethanol, glycerol, and sugar content could be easily obtained. The subsequent multivariate data analysis using partial linear least-squares regression type 2 enabled the quantitative monitoring of all reactants within a single model in real time.


Assuntos
Etanol/análise , Química Verde , Análise Espectral Raman , Fermentação , Espectroscopia de Ressonância Magnética
2.
RSC Adv ; 9(17): 9783-9791, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35520694

RESUMO

Antimicrobial finishes for textiles and other surfaces that act without the release of biocides to the environment (contact biocides) or by inhibiting microbial adhesion (antifouling action) are viewed as promising and environmentally friendly alternatives to current products. We have used polyvinylamine polymers that were functionalized with zwitterionic sulfobetaine side chains with different degrees of substitution (DS) for the finishing of poly(ethylene terephthalate) (PET) and cotton fabrics in a water-based pad-dry-cure process. After washing with different surfactants, a stable finish with total polymer add-ons of 0.2-0.5 wt% was achieved. The finished textiles efficiently inhibited the adhesion of proteins and bacteria to the surface even with a small DS as low as 20%. Textiles finished with polymers with a low DS also showed significant antibacterial activity, most notably against Staphylococcus aureus. Accordingly, textile finishes with either pure antiadhesive (DS > 50%) or combined antiadhesive and antibacterial properties (DS = 20-50%) are accessible using this approach.

3.
Int J Med Mushrooms ; 20(11): 1107-11119, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30806234

RESUMO

Lentinus edodes (shiitake) ranks among the most well-known medicinal mushrooms worldwide. Immune-modulating effects of shiitake extracts have been widely demonstrated in animals and humans. Apart from providing highly purified compounds such as lentinan, crude mushroom extracts also show antitumor activities. The direct cytotoxicity of crude preparations still requires investigation. The focus of our study lies in the molecular weight cutoff distribution of ß-glucans and proteins in a cold aqueous extract from L. edodes. We applied cross-flow ultrafiltration to obtain 6 fractions with different molecular sizes. ß-glucan and protein contents were quantified. We were able to show that only small amounts of ß-glucans were extracted and that protein content decreases with fraction size. The cytotoxic potential of the cold aqueous preparation was demonstrated by analyzing inhibition of the growth of non-small cell lung cancer and triple-negative breast cancer cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cogumelos Shiitake/química , Ultrafiltração/métodos , Células A549 , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Humanos
4.
Int J Med Mushrooms ; 18(8): 671-680, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27910785

RESUMO

ß-glucans from Basidiomycetes like Grifola frondosa (the maitake mushroom) are well known for their health benefits. Polysaccharide preparations from medicinal mushrooms such as G. frondosa have been successfully tested in a vast number of studies. Many mushroom extracts have been developed and today are merchandized for use medicinally and commercially. Studies could show that, in particular, chemical structural features such as the molecular size of ß-glucans significantly influence their bioactivity. Thus it is highly important to explore the composition and structural properties of ß-glucans extracted from medicinal mushrooms and their effects on human tumor cell viability. Our study focuses on the molecular weight cutoff distribution of ß-glucans in hot water-based extracts from maitake mushrooms. Cross-flow ultrafiltration was applied to obtain 5 fractions of different molecular size. ß-glucan content was quantified using an enzyme-based test kit, specialized to 1,3-1,6-ß-glucans. Here we show that only small amounts of ß-glucans with a high molecular weight (>100 kDa) could be detected from an aqueous extract of G. frondosa. The main compounds encompass substances with a low molecular weight (<5 kDa), composing about 35% of the whole extract. In addition, tumor cell viability studies demonstrate significant cytotoxic potential in 2 different solid cancer cell types for the fraction with a high molecular weight (>100 kDa) and for 1 fraction with a low molecular weight (5-10 kDa). In summary, our experiments prove that cross-flow ultrafiltration serves as a quick and easy method for dividing crude aqueous mushroom extracts into different molecular-weight fractions that inhibit tumor cell viability in vitro.


Assuntos
Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Grifola/química , Células A549 , Antineoplásicos/química , Humanos , Células MCF-7 , beta-Glucanas/química , beta-Glucanas/farmacologia
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