Synergistic effects of probiotic Leuconostoc mesenteroides and Bacillus subtilis in malted ragi (Eleucine corocana) food for antagonistic activity against V. cholerae and other beneficial properties

Abstract

Finger millet (Elucine corocana), locally known as ragi, and probiotics have been recognized for their health benefits. In the present work we describe novel probiotic ragi malt (functional food) that has been prepared using ragi and probiotic Leuconostoc mesenteroides (Lm) and Bacillus subtilis natto (Bs), alone and in combination, for antagonistic activity against Vibrio cholerae (Vc). In vitro studies using pure cultures showed that each probiotic strain (Lm or Bs) was able to inhibit the planktonic growth of Vc as well as its ability to make biofilms and adhere to extracellular matrix proteins (fibronectin, Fn) that may function in vivo as initial ports of entrance of the pathogen. Interestingly, the combination of both probiotic strains (Lm plus Bs) produced the strongest activity against the Vc. When both cultures were used together in the ragi malt the antimicrobial activity against Vc was enhanced due to synergistic effect of both probiotic strains. The inclusion of both probiotic strains in the functional food produced higher amounts of beneficial fatty acids like linoleic and linolenic acid and increased the mineral content (iron and zinc). The viability and activity of Lm and Bs against Vc was further enhanced with the use of adjuvants like ascorbic acid, tryptone, cysteine hydrochloride and casein hydrolysate in the ragi malt. In sum, the intake of probiotic ragi malt supplemented with Lm and Bs may provide nutrition, energy, compounds of therapeutic importance and antagonistic activity against Vc to a large extent to the consumer.

Transcriptional regulation of adhesive properties of Bacillus subtilis to extracellular matrix proteins through the fibronectin‐binding protein YloA

“…The specific and high adherence ability of Bs n to fibronectin (Fig. ) suggested that this property would be of importance for the enhancement of the beneficial properties of this probiotic strain in the host gastrointestinal tract (Duc et al ., ; Hosoi and Kiuchi, ; Hong et al ., ; Mackowiak, ; Vidyalaxme et al ., ; Donato et al ., ). Supporting this hypothesis, our in vitro experimental evidences suggested the suitability of probiotic RG4365 B. subtilis cells to efficiently interfere with the fibronectin‐binding proficiency of different Gram‐positive pathogens (Fig.…”

“…Even though the abundant information related to the biochemistry of ECM‐binding adhesins, very little is known about its genetic regulation. One attractive probiotic and genetically‐tractable model‐organism to investigate the genetic regulation of adherence to ECM components and competition with the adherence of bacterial pathogens is B. subtilis (Kearns et al ., ; Willians, ; Hong et al ., ; Vidyalaxme et al ., ; Grau et al ., ; Hanifi et al ., ; Donato et al ., ). In the present study, we characterize the adhesive properties of different wild strains of B. subtilis to components of the ECM and identify a novel gene encoding for a fibronectin‐binding protein and its genetic regulation.…”

“…The most common microorganisms used as probiotics are lactic acid bacteria, LAB, (Lee et al, 2011). In addition to LAB, some beneficial spore-forming bacteria of the genus Bacillus (i.e., B. subtilis and B. coagulans) have emerged as a new type of probiotic for human consumption (Senesi et al, 2004;Willians, 2007;Endres et al, 2009;Feldman et al, 2009;Cutting, 2011;Benson et al, 2012;Vidyalaxme et al, 2014;Donato et al, 2017). The difference between probiotic bacilli and LAB primarily relies on two beneficial properties: refrigeration is not required for maintaining bacilli viability, and these bacteria can be added to a wide range of foods and beverages in addition to dairy products (Duc et al, 2004;Bar ak et al, 2005;Cutting, 2011).…”

Antimicrobial Effect of Probiotics against Common Pathogens

“…Probiotic candidates have been accessed from very diverse habitats including faeces of breastfed human infants [65,69,80,85,95], faeces of healthy adults [9,15,65,70], faeces of elderly [81], faeces of children [25,96], breast milk [42], human saliva [52], vaginal isolates of healthy women [66,75], various fermented foods or beverages including raw or fermented milk [23,35,44], kefir [97], cheese [51,56,98], whey [99], yogurt [16,41], dahi [100,101], other dairy products [25,36,61], sourdough [102], sausages [17], fermented meat [24], kimchi [10,62], maize [25,59], fermented olives [103], Yerba mate [79], ragi [64], soy sauce [86], soil [104], as well as animal origin including rat faeces [71], geese [68], c...…”

Personalized Probiotics Based on Phenotypes and Dietary Habit: A Critical Evaluation

“…Probiotics with demonstrated antagonistic interaction with pathogens [28,29] would benefit people living in unhygienic environment but may impart no obvious benefit to people living in modern hygienic cities. Interestingly, GI Enterococcus faecalis which is an opportunistic and nosocomial pathogen [30,31] may serve to modulate inflammatory responses of children in unhygienic condition [32,33].…”