# Probiotics and Beneficial Microorganisms in Biopreservation of Plant-Based Foods and Beverages
## 4 Biopreservative Properties of Probiotics  
The major mechanisms of probiotic activity in the human body are depicted in Figure 1. Antimicrobial properties are one of the core benefits associated with probiotics. A number of commercially used probiotics and beneficial microorganisms have demonstrated various inhibitory actions against a variety of pathogenic and spoilage microorganisms in foods. The study of mechanisms of probiotic action reveals novel functions of probiotic microor \begin{table}
\begin{tabular}{c c c} \hline \hline
**Genus** & **Probiotic/Potential Probiotic** & **Food Matrix** & **Reference** \\ \hline _Lactobacillus_ & _Lactobacillus rhamnus_ GG & Kefir & [36] \\ _Lactobacillus casei_ ATCC 393 & Fermented milk & [37] \\ _Lactobacillus casei_ Q14 & Yoghurt & [38] \\ _Lactobacillus casei_ 01 & Sheep milk ice cream & [39] \\ _Lactobacillus paracasei_ LBC-81 & Maize-based beverage & [40] \\ _Lactobacillus plantarum_ L7 & Rice-based fermented & [41] \\ _Lactobacillus acidophilus_ NCIMB 8821 & Oat flour and barley malt beverage & [42] \\ _Lactobacillus reuteri_ NCIMB 11951 & Oat flour and barley malt beverage & [42] \\ _Lactobacillus fermentutum_ ATCC 9338 & Prickly pear juice & [43] \\ _Lactobacillus fermentutum_ KKL1 & Rice-based fermented & [44] \\ _Bifthobacterium_ & _B. longum_ subsp. longum YS108R & Fermented milk & [45] \\ _B. antimalis_ & Milk supplemented with seaweed extract & [46] \\ _B. breve_ & Probiotic-fermented blended juices & [47] \\ _Saccharomyces_ & _Saccharomyces cerevisiae_ KU200284 & Kefir & [48] \\ _Pediococcus_ & _Pediococcus pentosacues_ Lbf2 & Soursop juice & [49] \\ _Pediococcus_ & _Pediococcus_ & Antibiotic orange juice & [50] \\ _Propionibacterium_ & _Propionibacterium_ & _Propionibacterium_ & _Propionibacterium_ \\  & subsp. shermani & & \\ _Streptococcus_ & _Streptococcus thermophilus_ & Probiotic chocolate, novel probiotic fermented & [53; 54] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Commonly used probiotics and beneficial microorganisms in dairy and non-dairy plant-based food products. ganisms. A clear understanding of the mode of action enables the selection of suitable probiotic strains for specific applications. The antagonistic effects of the probiotics on other microorganisms may be due to a number of mechanisms including gut microbiota modification, enhanced gut epithelial barrier, increased adherence to the epithelium and intestinal mucosa, and immune system modulation to offer benefits to the host [55]. However, not all of these mechanisms are important for their biopreservative properties. The production of antimicrobial substances seems to be the main contributor to the biopreservative properties of probiotics. The mechanism of probiotics' antimicrobial activity is largely associated with the formation of organic acids, ethanol, and bacteriocins and thereby the inhibition of foodborne and spoilage microorganisms present in food material [56]. Hence, bacteriocin production by probiotic microorganisms can be considered as an integral part of their antagonistic ability in biopreservation. However, this phenomenon warrants further research. Research dedicated to investigating the antimicrobial properties of the probiotics, as well as potential probiotic strains, provides suggestions for a long list of potential candidates that can be used as biopreservative agents in plant-based foods. For instance, [PERSON] et al. [57] reported the antimicrobial properties of _Lactobacillus kefri_ which is a potent probiotic strain isolated from kefri grains. Co-culturing of _Bifidobacterium longum_IPLA2002 and _Bifidobacterium breve_IPLA20006 in the presence of short-chain fructologosaccharides as carbon source significantly reduces the growth of pathogenic _Clostridium difficile_[58]. Among these, potential probiotic strains isolated from food sources have the great advantage of using as biopreservative agents in another food matrix.