Characterization of a <i>Lactiplantibacillus plantarum</i> R23 Isolated from Arugula by Whole-Genome Sequencing and Its Bacteriocin Production Ability

• Main Authors: Joana Barbosa, Helena Albano, Beatriz Silva, Maria Helena Almeida, Teresa Nogueira, Paula Teixeira
• Format: Article
• Language: English
• Published: MDPI AG 2021-05-01
• Series: International Journal of Environmental Research and Public Health
• Subjects: bio-preservation; Coagulin A; food safety; pediocin; plantaricin; starter culture
• Online Access: https://www.mdpi.com/1660-4601/18/11/5515
• ISSN: 1661-7827; 1660-4601

<i>Lactiplantibacillus plantarum</i> is one of the lactic acid bacteria species most used as probiotics and starter cultures in food production. Bacteriocin-producers <i>Lpb. plantarum</i> are also promising natural food preservatives. This study aimed to characterize <i>Lpb. plantarum</i> R23 and its bacteriocins (R23 bacteriocins). The genome sequence of <i>Lpb. plantarum</i> R23 was obtained by whole-genome sequencing (WGS) in an Illumina NovaSeq platform. The activity of <i>Lpb. plantarum</i> R23-produced bacteriocin against two <i>Listeria monocytogenes</i> strains (L7946 and L7947) was evaluated, and its molecular size was determined by tricine-SDS-PAGE. No virulence or antibiotic resistance genes were detected. Four 100% identical proteins to the class II bacteriocins (Plantaricin E, Plantaricin F, Pediocin PA-1 (Pediocin AcH), and Coagulin A) were found by WGS analysis. The small (<6.5 kDa) R23 bacteriocins were stable at different pH values (ranging from 2 to 8), temperatures (between 4 and 100 °C), detergents (all, except Triton X-100 and Triton X-114 at 0.01 g/mL), and enzymes (catalase and α-amylase), did not adsorb to the producer cells, had a bacteriostatic mode of action and their maximum activity (AU/mL = 12,800) against two <i>L. monocytogenes</i> strains occurred between 15 and 21 h of <i>Lpb. plantarum</i> R23 growth. <i>Lactiplantibacillus plantarum</i> R23 showed to be a promising bio-preservative culture because, besides being safe, it produces a stable bacteriocin or bacteriocins (harbors genes encoding for the production of four) inhibiting pathogens as <i>L. monocytogenes</i>. Further studies in different food matrices are required to confirm this hypothesis and its suitability as a future starter culture.