Antimutagenic and Antibacterial Activity of beta-Cyclodextrin Clathrates with Extensive Hydrolysates of Colostrum and Whey
BIOINTERFACE RESEARCH IN APPLIED CHEMISTRY
Authors: Halavach, Tatsiana M.; Savchuk, Ekaterina S.; Bobovich, Angelina S.; Dudchik, Natalia, V; Tsygankow, Vasili G.; Tarun, Ekaterina, I; Yantsevich, Aleksei, V; Kurchenko, Vladimir P.; Kharitonov, Vladimir D.; Asafov, Vladimir A.
Abstract
: In this study, experimental samples of extensive enzymatic hydrolysates of bovine colostrum and whey, inclusion complexes of beta-cyclodextrin with dairy peptides were derived. 1.6-fold increase in the degree of proteolysis was established for whey hydrolysate compared to cleaved first milk.A significant decline in the bitterness of peptide constituents of clathrates was recorded versus samples of initial extensive hydrolysates. The thermogravimetric analysis confirmed the formation of inclusion complexes of cyclic oligosaccharide with dairy peptides. The Ames test demonstrated comparable induced mutation rates for samples of hydrolysates and clathrates. Antimutagenic activity of the samples reached 23.928.3 % when tested on strain Salmonella typhimurium TA 98 and 19.421.8 % on strain TA 100. According to the impedimetric method, the antibacterial potential of extensive colostrum hydrolysate exceeded the action of cleaved whey against Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 6538. Enhanced antibacterial activity was found for whey and colostrum peptide fractions included in clathrates with a cyclic oligosaccharide. SS-cyclodextrin complexing preserved antimutagenic capacity, promoted antibacterial effect, and improved organoleptic properties of milk peptides. These advantages acquire maximum relevance during the clathrate upgrading of specialized nutrition formulas
Differentiation of meat-related microorganisms using paper-based surface-enhanced Raman spectroscopy combined with multivariate statistical analysis
TALANTA
Authors: Breuch, Rene; Klein, Daniel; Siefke, Eleni; Hebel, Martin; Herbert, Ulrike; Wickleder, Claudia; Kaul, Peter
Abstract
Surface-enhanced Raman spectroscopy (SERS) with subsequent chemometric evaluation was performed for the rapid and non-destructive differentiation of seven important meat-associated microorganisms, namely Brochothrix thermosphacta DSM 20171(T), Pseudomonas fluorescens DSM 4358, Salmonella enterica subsp. enterica sv. Enteritidis DSM 14221, Listeria monocytogenes DSM 19094, Micrococcus luteus DSM 20030(T), Escherichia coli HB101 and Bacillus thuringiensis sv. israelensis DSM 5724. A simple method for collecting spectra from commercial paper-based SERS substrates without any laborious pre-treatments was used. In order to prepare the spectroscopic data for classification at genera level with a subsequent chemometric evaluation consisting of principal component analysis and discriminant analysis, a data pre-processing method with spike correction and sum normalisation was performed. Because of the spike correction rather than exclusion, and therefore the use of a balanced data set, the multivariate analysis of the data is significantly resilient and meaningful. The analysis showed that the differentiation of meat-associated microorganisms and thereby the detection of important meatrelated pathogenic bacteria was successful on genera level and a cross-validation as well as a classification of ungrouped data showed promising results, with 99.5% and 97.5%, respectively.