Isolation of lactic acid bacteria from Northwest Argentinean pseudocereal flour and grains. Evaluation of B group vitamin production

CARRIZO, S.L.; JUAREZ DEL VALLE, M.; LAIÑO, J. E.; VIGNOLO, G.; LEBLANC, J.G.; ROLLAN, G.

Egmond aan Zee

Simposio; 11th International Symposium on Lactic Acid Bacteria; 2014

The pseudocereals quinoa (Chenopodium quinoa) and amaranth (sp.) are ancient Andean crops with high nutritional value; they contain elevated concentrations of proteins, and different levels of vitamins and minerals. However, many of these compounds are altered or removed during milling, processing or cooking. Lactic acid bacteria (LAB) are widely used as starter cultures for the fermentation of different foods. LAB are usually auxotrophic for several vitamins although some strains have the ability to synthesize B vitamins, suggesting that the use of adequately selected strains could increase the concentration of these vitamins in fermented foods and their nutritional value. The aim of this study was to evaluate the LAB microbiota of quinoa and amaranth flour and grains of Northwestern Argentina (NOA) and determine their capacity to produce B vitamins, folate (B9) and riboflavin (B2). LAB were identified by biochemical and molecular methods. More than seventy strains of LAB were isolated and identified as belonging to the species Lactobacillus (L.) pentosus, L. rhamnosus, L. sakei and L. plantarum. Intra-, extracellular and total concentrations of B2 and B9 were determined using microbiological methods. Of the total tested strains, most grew on the B2 free medium and produced different levels of this vitamin (between 0.08 and 285 ng / ml), Almost 90% of the isolated LAB grew in synthetic medium without B9 and produced between 14 and 80 ng / ml.The results obtained put in evidence that native LAB isolated from quinoa and amaranth from NOA, produce significant levels of vitamin B2 and B9, indicating their potential to be included as starter cultures in pseudocereals containing food preparation with higher nutritional value.