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Summary: Vegetable and fruit snacks emerge as an innovative non‐dairy functional food of probiotic carriers and a valuable alternative to consumers with dietary restrictions. However, enriching snacks with probiotics is challenging as several factors may affect cell viability making it difficult to maintain adequate microbial doses at consumption time. This article aimed to review the most recent advances in the design of probiotic fruit and vegetable snacks to provide the current state of knowledge on this cutting‐edge topic. In particular, the technologies applied to introduce probiotics into the food matrix, classical and novel drying methods, and strategies to improve microbial survival during processing, storage and gastrointestinal passage, are discussed. Most of the published works report bacterial counts above 7 log cfu g−1 in snacks, which is a proper dose of probiotics to promote health benefits. However, many of these studies did not evaluate the survival rate during storage or considered short periods. The design of fruit‐ or vegetable‐based snacks enriched with probiotics appears to be a worthwhile strategy at laboratory scale but further studies to validate results both at pilot and industrial scale are necessary. [ABSTRACT FROM AUTHOR]

Vitamin B12 or cobalamin is an essential metabolite for humans, which makes it an interesting compound for many research groups that focus in different producer-strains synthesis pathways. In this work, we report the influence of key intermediaries for cobalamin synthesis added to the culture medium in two Lactobacillus (L.) strains, L. reuteri CRL 1098 and L. coryniformis CRL 1001. Here, we report that addition of Co2+ and 5,6-dimethylbenzimidazole increased the corrinoid compounds production in both strains while addition of L-threonine increased only the corrinoid compounds production by CRL 1001 strain. Then, we purified and characterized by LC-MS the corrinoid compounds obtained. Physiological studies besides in silico analysis revealed that L. reuteri CRL 1098 and L. coryniformis CRL 1001 follow different pathways for the last steps of the corrinoid compounds synthesis. [ABSTRACT FROM AUTHOR]

In artisanal tanneries, the skins are immersed in cereals fermented by natural microbial flora in order to reduce the pH of the skin, an essential condition for carrying out the final step. The environmental thermal variation alters the fermentation process and affects the quality of the final product. The aim of this work was to isolate lactic acid bacteria from cereals mixture fermented in an artisanal tannery and to evaluate in vitro the acidifying activity of the strains as a first step for the formulation of a starter culture. In most samples, a prevalence of cocci (95%) was observed with respect to bacilli. The best acidifying strains were identified by phenotypic and genotypic techniques as Enterococcus faecium CRL 1943 (rapid acidification at 37 °C) and Leuconostoc citreum CRL 1945 (high acidifying activity at 18 °C). In addition, the biomass production of the selected strains was analyzed at free and controlled pH (bioreactors 1.5 L). The production of biomass was optimal at controlled pH, with a higher growth (0.5–1.1 log units). Both strains were compatible, allowing their inclusion in a mixed culture. These lactic strains could contribute to the systematization of the tanning process. [ABSTRACT FROM AUTHOR]

Background: Despite the fact that most vitamins are present in a variety of foods, malnutrition, unbalanced diets or insufficient intake of foods are still the cause of vitamin deficiencies in humans in some countries. Vitamin B12 (Cobalamin) is a complex compound that is only naturally produced by bacteria and archea. It has been reported that certain strains belonging to lactic acid bacteria group are capable of synthesized water-soluble vitamins such as those included in the B-group, as vitamin B12. In this context, the goal of the present paper was to evaluate and characterize the production of vitamin B12 in Lactobacillus coryniformis CRL 1001, a heterofermentative strain isolated from silage. Results: Cell extract of L. coryniformis CRL 1001, isolated from silage, is able to correct the coenzyme B12 requirement of Salmonella enterica serovar Typhimurium AR 2680 in minimal medium. The chemical characterization of the corrinoid-like molecule isolated from CRL 1001 cell extract using HPLC and mass spectrometry is reported. The majority of the corrinoid produced by this strain has adenine like Coα-ligand instead 5,6-dimethylbenzimidazole. Genomic studies revealed the presence of the complete machinery of the anaerobic biosynthesis pathway of coenzyme B12. The detected genes encode all proteins for the corrin ring biosynthesis and for the binding of upper (β) and lower (α) ligands in one continuous stretch of the chromosome. Conclusions: The results here described show for the first time that L. coryniformis subsp. coryniformis CRL 1001 is able to produce pseudocobalamin containing adenine instead of 5,6-dimethlbenzimidazole in the Coα-ligand. Genomic analysis allowed the identification and characterization of the complete de novo biosynthetic pathway of the corrinoid produced by the CRL 1001 strain. [ABSTRACT FROM AUTHOR]