Spirulina platensis as a super prebiotic to enhance the antibacterial effect of Lactobacillus casei.

• Assessing the effect of prebiotic on Lactobacillus casei. • Combining Spirulina platensis and L. casei. • Using molecular studies to confirm the mixture efficacy. • The present work elucidated the magnificent role of Spirulina as an immunomodulatory agent through being a prebiotic agent to mediate the antibacterial responses of L. casei. Microalgae are diminutive unicellular magnificent creatures that exist in the microscopic form. Within this classification, two notable subtypes, namely Spirulina platensis and Chlorella vulgaris , have garnered significant attention. S. platensis is mostly known for its therapeutic benefits due to proteins, vitamins, essential amino acids, minerals, and essential fatty acids abundance. The subsequent work aimed to investigate the prebiotic effect of S. platensis enhancing Lactobacillus casei microbiome growth rate and antibacterial effect. Different concentrations of S. platensis were prepared (0, 0.5, 5, and 50 mg/mL) then co-cultured with L. casei. Live probiotic enumeration, molecular characterization and scanning electron microscopy studies were performed. Data revealed that 5 mg/mL of S. platensis significantly enhanced the probiotic live count and consequently the antibacterial activity. The antibacterial and antibiofilm effects of L. casei / S. platensis mixture showed complete inhibition to the growth of bacterial cells after 4- and 8-h incubation with Staphylococcus epidermidis 12228 and Escherichia coli 25922, respectively. Moreover, minimal biofilm eradication concentration (MBEC) value of 16 µg/mL was recorded for L. casei / S. platensis mixture [ABSTRACT FROM AUTHOR]