Guest Lecture Flashcards
Why use probiotics
Natural benefits
Restore microbial balance
Safe alternative/ complement to medicines
Localised or systemic ebenfits
Origins of probiotics
Commensal bacteria
Dominate target surface (pathogen exclusion)
Properties of bacteria to be successful probiotics
Safe
Commensal of target site (sticks around)
Competitor exclusion
Anti-competitor behaviour eg production of bacteriocins, metabolites
Production of enzymes
Sensitive to common antibiotics
Actions of probiotics
Immune system modulation
Biofilm modulation
Production of beneficial enzymes
Colonisation
Exclusion by binding and blocking others
Killing (bacteriocin)
What does Blis make
Orobiotics for the oral cavity
Discovery of S.salivarius with probiotic potential
Found from studying children with sore throats
Dominant commensal on human tongue (also in breast milk and intestine)
Found in certain foods (cheese)
Early coloniser of newborns and stays for life
Demonstrates desirable properties of probiotic (natural site, colonisation, antibacterials)
What makes BLIS probiotics unique
Commensal to oral cavity (mouth, throat, teeth)
Produce bacteriocin-like inhibitory substances (BLIS)- small peptide missiles and generally kill closely related bacteria incl pathogenic bacteria
Many modes of action
Are not produced by all bacteria
Focus on BLIS producing probiotics
Colonises and protects oral cavity from pathogens
Patented strains (S.salivarius K12 in oral cavity infections, M18 in dental infections)
Clinical efficacy of daily S.salivarius K12 probiotic use
Led to reduced occurrence of sore throat and otitis media
90% reduction in infection rate during trial period
65% continued reduction 3 months post intervention
Reduced need for antibiotics
Development of a new probiotic
Selection stage- identify lead candidates, history of strain
Development- safety, stability, efficacy, pilot clinical trials, final product format, full clinical trials
Production- inhouse vs outsource, quality assurance
Selection stage
Strain screening (in vitro analysis- colonisation/ BLIS/ enzymes/ adherence)
Lead candidates undergo background checks (safety, genome/ transcriptome, literature search, legal/ freedom to operate)
Patent strain/ deposit
Development
Fermentation (cell production)
Stability (shelf life testing, accelerated stability based on climate, packaging)
Safety (mammalian models, animal trials dose response and toxicity, human trial- can outsource to eliminate conflict of interest)
Efficacy- is it optimal strain (further in vitro testing including broadening of initial screen parameters, immune effects)
Final product format (needs to closely match format used in clinical trials used to make claims of efficacy)
Full clinical trials (initial pilot trials good, large scale trials need to be designed with market in mind- what claims do you want to make)
Production
Inhouse vs outsource (size of fermentation, contract vs in house adv and disadv, cost/ expertise/ facilities/ control of operation eg timing)
Quality assurance (assurance and procedures for a safe product, why, monitoring, continual
Goals of fermentation
High yield
High cell count (CFU/g)
Retains key features eg plasmids
Stable product (key)
Safe: genetically stable, free from pathogens, heavy metals, foreign matter or cross contamination
Probiotic fermentation process
Media prep- make inoculum- used to inoculate main 5000L fermenter
Ultra high temp sterilisation- cells clarified and mixed with lyoprotectant
Fermenter
Centrifuge
Concentrate vessel
Freeze dryer- snap frozen and freeze dried
After fermentation
Milled
Quality check
Bagged and sold
