The in vitro effects of artificial and natural sweeteners on the immune system using whole blood culture assays

This article investigates the effects of commercially available artificial (aspartame, saccharin, sucralose) and natural sweeteners (brown sugar, white sugar, molasses) on the immune system. Human whole blood cultures were incubated with various sweeteners and stimulated in vitro with either phytohemagglutinin or endotoxin. Harvested supernatants were screened for cytotoxicity and cytokine release. Results showed that none of the artificial or natural sweeteners proved to be cytotoxic, indicating that no cell death was induced in vitro. The natural sweetener, sugar cane molasses (10 ug=mL), enhanced levels of the inflammatory biomarker IL-6 while all artificial sweeteners (10 ug=mL) revealed a suppressive effect on IL-6 secretion (P<0.001). Exposure of blood cells to sucralose-containing sweeteners under stimulatory conditions reduced levels of the biomarker of humoral immunity, Interleukin-10 (P<0.001). The cumulative suppression of Interleukin-6 and Interleukin-10 levels induced by sucralose may contribute to the inability in mounting an effective humoral response when posed with an exogenous threat.Web of Scienc

Biotechnological production and application of fructooligosaccharides

Currently, prebiotics are all carbohydrates of relatively short chain length. An important group is the fructooligosaccharides, which are a special kind of prebiotics associated to their selective stimulation of the activity of certain groups of colonic bacteria that have a positive and beneficial effect on intestinal microbiota, reducing incidence of gastrointestinal infections, respiratory and also possessing a recognized bifidogenic effect. Traditionally, these prebiotic compounds have been obtained through extraction processes from some plants, as well as through enzymatic hydrolysis of sucrose. However, different fermentative methods have also been proposed for the production of fructooligosaccharides, such as solid-state fermentation utilizing various agroindustrial by-products. By optimizing the culture parameters, fructooligosaccharides yields and productivity can be improved. The use of immobilized enzymes and cells has also been proposed as being an effective and economic method for large-scale production of fructooligosaccharides. This paper is an overview on the results of recent studies on fructooligosacharides biosynthesis, physicochemical properties, sources, biotechnological production and applications.The authors thank the National Council of Science and Technology of Mexico (CONACYT) for funding this study. D. A. Flores-Maltos thank the CONACYT for the financial support provided for her postgraduate studies in the Food Science and Technology Program, Universidad Autonoma de Coahuila, Mexico

Application of Experimental Designs for Optimization the Production of <em>Alcaligenes Faecalis</em> Nyso Laccase

713-722A sequential optimization strategy based on statistical experimental designs was implemented in order to enhance laccase production by a local isolate Alcaligenes faecalis NYSO in a submerged culture. To screen the parameters significantly influencing the laccase productivity, a 2-level Plackett-Burman design was applied. Among the studied variables, the pH, yeast extract, (NH4)2SO4, glucose, and CuSO4.5H2O were selected based on their high positive significant effect on laccase productivity. In order to find out the combination among the most significant variables that brings maximum yield, Response Surface Methodology was applied, where a 3-level Box-Behnken design was utilized to create a polynomial quadratic model correlating the relationship between the five variables and the laccase productivity. The optimal combination of the major medium constituents for laccase production was evaluated using the JMP program, was as follows: yeast extract, 0.896%; (NH4)2SO4, 0.035%; CuSO4.5H2O, 0.0075%; FeSO4.7H2O, 0.000133%; glucose, 0.0943%, pH 10.6 and 30 oC for 24 hrs. The predicted optimum laccase activity was 791U ml-1 min-1, which was 700 times the activity with basal medium. In addition, the further optimization for both pH, CuSO4.5H2O concentration lead the yield to be 2435 U ml-1min at pH 11.0, 200 mg CuSO4.5H2O which achieved after 18 hrs incubation time