Comparison of two ELISA methods with commercially available antibodies for prolamin detection in beer

Tradycyjne piwo produkowane jest najczęściej ze słodu jęczmiennego. Ok. 75% białek jęczmienia stanowią polipeptydy tworzące gluten, z czego 50% to prolaminy, a 25% gluteniny. Ze względu na skład surowcowy spożywanie piwa przez osoby z nadwrażliwością na gluten może wywołać niepożądane reakcje organizmu. Celem pracy było oznaczenie prolamin w dostępnych na rynku piwach za pomocą bezpośredniej i pośredniej metody ELISA oraz porównanie możliwości detekcyjnych stosowanych komercyjnie dostępnych przeciwciał. Stwierdzono, że większymi możliwościami detekcyjnymi hordein w piwie charakteryzowały się antygliadynowe przeciwciała znakowane enzymatycznie stosowane w metodzie ELISA bezpośrednia.Traditional beer is made by barley malt. Approx. 75% of the barley proteins are polypeptides formin gluten, of which 50% is prolamines and 25% glutenins. Due to composition of beer consumption by persons with hyperintensitivity to gluten can cause adverse reactions of the body. The aim of this study was to determine the prolamins in beers available in the market with use of direct and indirect ELISA methods and compare detection possibilities of commercially available antibodies. It was found that enzymatically labeled antigliadin antibodies was characterized much more detection possibilities of hordeins in beer

Genetic Control of Biosynthesis and Transport of Riboflavin and Flavin Nucleotides and Construction of Robust Biotechnological Producers†

Summary: Riboflavin [7,8-dimethyl-10-(1′-d-ribityl)isoalloxazine, vitamin B2] is an obligatory component of human and animal diets, as it serves as the precursor of flavin coenzymes, flavin mononucleotide, and flavin adenine dinucleotide, which are involved in oxidative metabolism and other processes. Commercially produced riboflavin is used in agriculture, medicine, and the food industry. Riboflavin synthesis starts from GTP and ribulose-5-phosphate and proceeds through pyrimidine and pteridine intermediates. Flavin nucleotides are synthesized in two consecutive reactions from riboflavin. Some microorganisms and all animal cells are capable of riboflavin uptake, whereas many microorganisms have distinct systems for riboflavin excretion to the medium. Regulation of riboflavin synthesis in bacteria occurs by repression at the transcriptional level by flavin mononucleotide, which binds to nascent noncoding mRNA and blocks further transcription (named the riboswitch). In flavinogenic molds, riboflavin overproduction starts at the stationary phase and is accompanied by derepression of enzymes involved in riboflavin synthesis, sporulation, and mycelial lysis. In flavinogenic yeasts, transcriptional repression of riboflavin synthesis is exerted by iron ions and not by flavins. The putative transcription factor encoded by SEF1 is somehow involved in this regulation. Most commercial riboflavin is currently produced or was produced earlier by microbial synthesis using special selected strains of Bacillus subtilis, Ashbya gossypii, and Candida famata. Whereas earlier RF overproducers were isolated by classical selection, current producers of riboflavin and flavin nucleotides have been developed using modern approaches of metabolic engineering that involve overexpression of structural and regulatory genes of the RF biosynthetic pathway as well as genes involved in the overproduction of the purine precursor of riboflavin, GTP