The probiotic properties of Lactiplantibacillus plantarum isolated from plant material

Aim. To identify and study the probiotic properties of a typical representative of lactic acid bacteria isolated from maize sourdough. Methods. The sourdough was prepared by mixing flour with water, followed by incubation for 24 hours. The species identity of Lactiplantibacillus plantarum was determined based on phenotypic characteristics. Stress resistance was assessed by evaluating cell viability after exposure to artificial saliva, low-pH saline solution, and a mixture of bile and simulated duodenal juice. Antibiotic susceptibility was determined using the disk diffusion method with reference values, while autoaggregation ability was evaluated by cell sedimentation through centrifugation and absorbance measurement using a spectrophotometric method. Results. The isolate was identified as L. plantarum. Its survival rates under simulated conditions of the oral cavity, stomach, and duodenum were 97.13±1.12%, 95.06±0.52%, and 91.67±1.66%, respectively. The strain was sensitive to erythromycin, ampicillin, and chloramphenicol, moderately sensitive to streptomycin and tetracycline, and resistant to benzylpenicillin and kanamycin. Autoaggregation levels after 2 and 24 hours were 6.88±0.1% and 41.83±0.4%, respectively. Conclusions. L. plantarum isolated from maize sourdough demonstrated high-stress resistance, sensitivity to several antibiotics (although resistance to kanamycin and benzylpenicillin requires further investigation), and sufficient autoaggregation capacity for a probiotic strain.