Bioinhibition of diarrhogenic Gram-positive bacterial pathogens by potential indigenous probiotics

High level infant mortality rates and onset of drug resistance has led into the possible development of indigenous probiotics as alternative bacteriotherapy in the control of infantile bacterial diarrhoea.This study was to determine the in vitro inhibitory potential of four probiotic candidates obtained from Nigerian indigenous fermented foods and beverages and from faecal specimens of healthy infants on infantile Gram-positive diarrhogenic bacterial pathogens.Potential probiotic candidates,AAOOL4,L.reuteri AAOOCH1,L.plantarum AA0025NN and L.delbrueckii AAOOT20 were assayed for in vitro bactericidal effects on diarrhogenic bacterial test strains-Bacillus cereus 25S,B.cereus 32S,B.licheniformis 26S and B.licheniformis 39S.All the test strains inoculated into an industrial infant weaning food already seeded with the probiotic strains were significantly inhibited within 96 hours.L.acidophilus AAOOL4,L.reuteri AAOOCH1,L.plantarum AAOO25NN and L.delbrueckii AAOOT20 had in vitro bactericidal effects on bacteri isolates implicated in infantile diarrhoea,indicating the probiotic potential of the candidates.

Evaluation of bacterial pathogens in paediatric polioviruspositive faecal specimens

Objective:To evaluate the in vitro inhibitory potential of commonly available antibiotic(discs) and paediatric suspensions against bacterial species from polio-positive faecal specimens.Methods:Commonly available antibiotic (discs) and oral,paediatric suspensions were screened for in vitro inhibitory activities against bacterial species from infantile polio-positive faecal specimens,using agar disc-diffusion and modified agar well-diffusion methods.Results:Isolated bacteria were Bacillus cereus,B.subtilis,Staphylococcus aureus,Streptococcus pneumoniae,Aeromonas hydrophila,Citrobacter aerogenes,Escherichia coli,Enterobacter aerogenes,Klebsiella pneumoniae,Pseudomonas aeruginosa,Proteus mirabilis,Pr.vulgaris,Shigella dysenteriae,Sh.flexneri,Sh. sonnei and Vibrio parahaemolyticus.Overall phenotypic antibiotic susceptibility rates among Gram-positive bacterial species were between 33.3%(augmentin) and 75.0%(chloramphenicol,erythromycin and gentamicin); higher susceptibility rates(48.6%-100.0%) were recorded among Gram-negative bacterial species, while between7.8%/ 10.1%(metronidazole / ampicillin) and 25.2%/28.1%(cotrimoxazole / septrin) were recorded towards paediatric antibiotics.Conclusions:Bacterial species from polio-positive fecal specimens are minimally susceptible to commonly available oral paediatric antibiotic suspensions in Nigeria.