Probiotic Properties of Lactic Acid Bacteria Newly Isolated from Algerian Raw Cow’s Milk

Abstract

This study aims to screen new LAB from Algerian cow’s milk to assess their probiotic properties. Molecular identification and MALDI-TOF mass spectrometry methods were used to identify the LAB isolates. The probiotic potential of isolates was determined with in vitro tests of survival to gastrointestinal conditions (pH 2, 0.3% pepsin, 0.5% bile salts, 0.1% trypsin, and 0.1% pancreatic amylase) and antimicrobial and antioxidant activities. Eight isolates were identified as Lactiplantibacillus plantarum (100%) and one isolate as Lacticaseibacillus rhamnosus (95.75%). The MALDI-TOF MS analysis of the isolates confirms that the strains belong to the group of lactobacilli bacteria, particularly Lactiplantibacillus plantarum. The high survival rate reflects a good strain tolerance to the in vitro host simulated gastrointestinal conditions. All bacteria exhibit an antibacterial activity strain with inhibition zone diameters ranging from 4.9 mm against Aspergillus niger ATCC 106404 to 17.47 mm against Candida albicans ATCC 10231. The antioxidant activity with the highest DPPH scavenging activity (92.15%) was obtained with the LbN09 strain. In light of these results, some of the strains isolated from raw milk of the local Algerian breed cows show promising probiotic properties, giving them a possible use in preserving food from microbial spoilage and oxidation during storage.

Exploring Phenotype, Genotype, and the Production of Promising GABA Postbiotics by Lactiplantibacillus plantarum: A Comprehensive Investigation

“…These findings contribute to the understanding of growth patterns under specific conditions and guide the optimization of bacterial cultures, probiotic formulation, fermentation processes, and antimicrobial research. The results are consistent with previous studies by Kouadri et al [34], who emphasized the robustness of Lactiplantibacillus plantarum strains in in vitro tests, simulating human gastrointestinal conditions.…”

Lacticaseibacillus Strains Isolated from Raw Milk: Screening Strategy for Their Qualification as Adjunct Culture in Cheesemaking

“…casei isolates that originate from raw cow's milk used for cheese manufacturing, as reported by Bancalari and colleagues, who used impedance analysis to measure isolates' technological performance and studied the volatile profile to identify potential adjunct strains for the dairy industry [17]. The raw milk was also used as a source for isolating potential probiotic strains [18][19][20] or starters LAB [21]. The advantage of isolating bacteria from raw milk rather than cheese may be the higher choice of species and strains since the raw milk arbors a higher biodiversity in comparison to the ripened cheese [22].…”