Influence of temperature, pH and salts on rheological properties of bitter almond gum

Abstract This study focuses on the rheological properties of bitter almond gum (BAG) exudate at different shear rates, concentrations, temperatures, pH, and in the presence of various salts. Rheological data fitted with the Power law model revealed that BAG solutions exhibit non-Newtonian, shear thinning behavior without thixotropic effects at all tested concentrations and temperatures. Apparent viscosity of BAG solutions increased with the increasing gum concentrations and decreased with the increasing shear rate at a specified temperature. The viscosity reached a maximum value at pH 7 and it decreased at lower and higher pH values. Salts caused a reduction in viscosity. Comparatively, CaCl2 had a more pronounced effect than NaCl at a similar concentration. All treatments had significant effects on rheological parameters

The Emulsifier Carboxymethylcellulose Induces More Aggressive Colitis in Humanized Mice with Inflammatory Bowel Disease Microbiota Than Polysorbate-80

Commonly used synthetic dietary emulsifiers, including carboxymethylcellulose (CMC) and polysorbate-80 (P80), promote intestinal inflammation. We compared abilities of CMC vs. P80 to potentiate colitis and impact human microbiota in an inflammatory environment using a novel colitis model of ex-germ-free (GF) IL10−/− mice colonized by pooled fecal transplant from three patients with active inflammatory bowel diseases. After three days, mice received 1% CMC or P80 in drinking water or water alone for four weeks. Inflammation was quantified by serial fecal lipocalin 2 (Lcn-2) and after four weeks by blinded colonic histologic scores and colonic inflammatory cytokine gene expression. Microbiota profiles in cecal contents were determined by shotgun metagenomic sequencing. CMC treatment significantly increased fecal Lcn-2 levels compared to P80 and water treatment by one week and throughout the experiment. Likewise, CMC treatment increased histologic inflammatory scores and colonic inflammatory cytokine gene expression compared with P80 and water controls. The two emulsifiers differentially affected specific intestinal microbiota. CMC did not impact bacterial composition but significantly decreased Caudoviricetes (bacteriophages), while P80 exposure non-significantly increased the abundance of both Actinobacteria and Proteobacteria. Commonly used dietary emulsifiers have different abilities to induce colitis in humanized mice. CMC promotes more aggressive inflammation without changing bacterial composition