TY  - JOUR
A1  - Garakani, Tayebeh Mirzaei
A1  - Richter, Marina Juliane
A1  - Böker, Alexander
T1  - Controlling the bio-inspired synthesis of silica
JF  - Journal of colloid and interface science
N2  - The influence of different parameters on the silicification procedure using lysozyme is reported. When polyethoxysiloxane (PEOS), an internally crosslinked silica reservoir, is used, regular structures with a narrow size distribution could be obtained only via introducing the silica precursor in two steps including initial dropping and subsequent addition of residual oil phase in one portion. We found that mixing sequence of mineralizing agents in the presence of a positively charged surfactant plays a key role in terms of silica precipitation when tetraethoxyorthosilicate (TEOS) is the oil phase. In contrast, well mineralized crumpled features with high specific surface area could be synthesized in the presence of PEOS as a silica precursor polymer, regardless of mixing sequence. Moreover, introducing sodium dodecyl sulfate (SDS) as a negatively charged surfactant resulted in regular silica sphere formation only in combination with hexylene glycol (MPD) as a specific co-solvent. Finally, it is demonstrated that by inclusion of different nanoparticles even more sophisticated hybrid materials can be generated.
KW  - Silicification
KW  - Lysozyme
KW  - Polyetlioxysiloxane
KW  - High specific surface area
KW  - Surfactant
KW  - Nanoparticles
KW  - Hybrid materials
Y1  - 2016
U6  - https://doi.org/10.1016/j.jcis.2016.10.069
SN  - 0021-9797
SN  - 1095-7103
VL  - 488
SP  - 322
EP  - 334
PB  - Elsevier
CY  - San Diego
ER  - 
TY  - JOUR
A1  - Mengibar, M.
A1  - Ganan, M.
A1  - Miralles, B.
A1  - Carrascosa, A. V.
A1  - Martinez-Rodriguez, Adolfo J.
A1  - Peter, Martin G.
A1  - Heras, A.
T1  - Antibacterial activity of products of depolymerization of chitosans with lysozyme and chitosanase against Campylobacter jejuni
JF  - Carbohydrate polymers : an international journal devoted to scientific and technological aspects of industrially important polysaccharides
N2  - Chitosan has several biological properties useful for the food industry, but the most attractive is its potential use as a food preservative of natural origin due to its antimicrobial activity against a wide range of food-borne microorganisms. Among food-borne pathogens, Campylobacter jejuni and related species are recognised as the most common causes of bacterial food-borne diarrhoeal disease throughout the world. Recently, it has been demonstrated that campylobacters are highly sensitive to chitosan. Even though chitosan is known to have important functional activities, poor solubility makes them difficult to use in food and biomedical applications. Unlike chitosan, the low viscosity and good solubility of chitosan oligosaccharides (COS) make them especially attractive in an important number of useful applications. In the present work, the effect of different COS on C. jejuni was investigated. Variables such as the physicochemical characteristics of chitosan and the enzyme used in COS preparation were studied. The COS had been fractioned using ultrafiltration membranes and each fraction was characterized regarding its FA and molecular weight distribution. It has been demonstrated that the biological properties of COS on Campylobacter depend on the composition of the fraction analysed. COS prepared by enzymatic hydrolysis with chitosanase were more active against Campylobacter that lysozyme-derived COS, and this behaviour seems to be related with the acetylation of the chains. On the other hand. the 10-30 kDa fraction was the most active COS fraction, independently of the enzyme used for the hydrolysis. These results have shown that COS could be useful as antimicrobial in the control of C. jejuni.
KW  - Campylobacter jejuni
KW  - Chitooligosaccharides
KW  - Chitosanase
KW  - Lysozyme
KW  - Depolymerization
Y1  - 2011
U6  - https://doi.org/10.1016/j.carbpol.2010.04.042
SN  - 0144-8617
VL  - 84
IS  - 2
SP  - 844
EP  - 848
PB  - Elsevier
CY  - Oxford
ER  -