Assessment of the antifungal and probiotic properties of three Lactiplantibacillus plantarum strains

Probiotic use has significantly increased in the past decades as their benefits are well known. Through several in vitro experiments, three strains of lactic acid bacteria (LAB) were tested for their antifungal and probiotic characteristics. The tested strains were defined as Lactiplantibacillus plantarum (Lp. plantarum), and they were designated as 2GP, 4FB, and 10SB; they were isolated from bee pollen, white sorghum, and opuntia ficus-indica fruits (prickly pear), respectively. The results obtained showed that the three LAB possess strong activity and a wide antifungal spectrum. In addition, they do not have any antibiotic resistance or inadequate virulence factors. There were many viable cells after multiple digestive stress factors that demonstrate that the three strains possess excellent resistance to simulated circumstances in the oro-gastro-intestinal tract. On examining their cell surface properties, the three strains showed a significant increase in percentages of pathogen co-aggregation, auto-aggregation, and hydrophobicity. In addition, the strains showed strong antibacterial activity versus three pathogenic bacteria, their antioxidant activity was between 53.09% and 59.95%, and they were able to generate exopolysaccharides. For the first time, three antifungal strains 2GP, 4FB, and 10SB belonging to the same species of Lp. plantarum and isolated from different biotopes have properties that allow them to be used safely as probiotics.