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The composition of intestinal microbiota is widely believed to not only affect gut health but also influence behaviour. This study aimed to evaluate the probiotic characteristics, antioxidant activity, and antidepressant- and anxiolytic-like activities of Lactococcus lactis subsp. cremoris LL95. This strain showed probiotic properties such as resistance in a simulated gastric tract model and survival at different concentrations of NaCl and bile salts. Moreover, antioxidant activity of LL95 was demonstrated through DPPH radical scavenging activity, scavenging of ABTS•+ radical and ferric ion reducing antioxidant power (FRAP) assays. Female C57BL/6 mice received LL95 orally at a dose of 109 UFC/day for 28 days. LL95 improved depressive- and anxiety-like behaviour, demonstrated by decreased immobility time in the tail suspension test and forced swim test and increased per cent of time spent in the open arms on the elevated plus maze. These findings indicate the potential antioxidant activity of LL95 and its role in behaviour, suggesting that probiotic may have therapeutic applications.

The aim of this study was to evaluate the probiotic potential and the viability in fermented oat dairy beverage of Lactobacillus curvatus isolate P99. Probiotic potential was assessed through the survival in simulated gastrointestinal tract conditions, autoaggregation, coaggregation, and hydrophobicity capacity and antimicrobial activity. The safety aspects of the isolate were evaluated for application in food, and these were determined by phenotypic and genotypic tests. Isolate P99 was able to survive in simulated gastrointestinal tract conditions and showed hydrophobicity, autoaggregation, and coaggregation with Listeria monocytogenes. Moreover, the isolate and its cell free supernatant showed antimicrobial activity against Gram‐positive and Gram‐negative microorganisms. L. curvatus P99 showed in vitro probiotic potential, fulfilled safety aspects, and remained viable for 35 days in fermented oat dairy beverage stored at 4°C. Moreover, probiotic fermented oat dairy beverage demonstrated high acceptability. Therefore, isolate P99 can be considered a promising microorganism for the manufacture of probiotic foods. Practical applications Probiotics are microorganisms capable of providing health benefits to the host. However, isolates with probiotic potential from foods, when used as adjuvant cultures in foods, promote desirable sensory attributes and ensure microbiologically safe food. In this study, we found that Lactobacillus curvatus P99 presented probiotic potential and remains viable for 35 days when used in the production of fermented oat dairy beverage. Therefore, isolate P99 can be considered a promising microorganism for the manufacture of probiotic foods.

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This study aimed to isolate lactic acid bacteria from sheep milk products and to characterize these microorganisms with a focus on their antimicrobial, proteolytic and lipolytic activities. Raw milk, pasteurized milk, pasteurized cream, and butter samples were collected, lactic acid bacteria were isolated and their proteolytic, lipolytic and antimicrobial activities were evaluated. Lactic acid bacteria counts were higher in raw milk collected at the farm number 4 (8.91 ± 0.05 log CFU/mL), in which adequate hygienic practices were observed for pre-and post-milking. A total of 253 isolates were obtained, and among them 37 were lactic acid bacteria, where 19 showed some type of activity, most of which from raw milk. Among the isolates of lactic acid bacteria, 48.65% (n=18) showed proteolytic activity, 13.51% (n=5) lipolytic activity, 10.81% (n=4) showed both proteolytic and lipolytic activities, and only 2.70% (n=1) showed antimicrobial activity. Osolation of lactic acid bacteria with technological properties demonstrated their potential use as starter cultures in processing of fermented dairy products.