I need help anwering questions 6-10 only. Thanks. 3. Suggest a control for this experiment?4. What is the optimal temperature range for Listeria monocyogenes? Is L. monocyogenes apsychrophile, psychrophile, mesophile, or themophile?5. What the optimal pH range for Lactobacillus plantarum? Is Lb. plantarum an acidophile,neutraphile, or alkalophile?6. What is the toxin produced by E. coli O157:H7 that was encode by phage as aconsequence of lysogenic conversion? Explain the medical importance.7. Which bacterial culture (Lb. plantarum, P. acidilactici, or P. pentosaceus) was mosteffective against L. monocytogenes and Salmonella? Explain why.8. What are the limitations of using an agar disk diffusion assay to assess theeffectiveness of an antiseptic, disinfectant, or, in this case, a biological control agenton the growth of bacteria of interest?9. LAB produce organic acids that have shown to be effective against controlling thegrowth of foodborne pathogens. What specific organic acid is produced by LAB duringfermentation?10. What is the logical next step to validate the efficacy of the biological control agent? Experiment #1 From Antoinette de Senna's Master's thesis on "Screening of biological controlorganisms for the management of phytopathogenic fungi and foodborne pathogens on produce".Objective: To screen three LAB (Lactobacillus plantarum, Pediococcus acidilactici, andPediococcus pentosaceus) for antimicrobial activity against the foodborne pathogens Listeriamonocytogenes, Salmonella, and Escherichia coli.Methods: 1 ml of the pathogen was placed into a petri dish. Then, 15-20 ml molten tryptic soyagar (TSA) tempered to 50°C was added. When the TSA solidified, a loopful of LAB wasspotted onto the agar. Plates were incubated at 35°C for 24 hours then the zone of inhibition wasmeasured from the boarder of the bacterial colony to the perimeter of the clearing.Results:LmonocytogenesSalmonellaE col O157-H7Questions:1. What is the independent variable?2. What is the dependent variable?Pacidilactici

Lactobacillus bacteria are found in rich carbohydrates containing products like milk, cheese, yogurt, fermented milk products and fermented beverages (example- wine and Cider) Lactobacillus Bacteria are a part of microbial flora in human blody. They are found in gastrointestinal system, urinary system and genital system. Lactobacillus Bacteria are present in human intestines, they protect the gut by preventing colonization of pathogen in gut. They are also present in vagina, they maintain the low vaginal pH by producing lactic acid . Lactobacillus are gram positive, rod shaped Bacteria. Interesting features of lactobacillus Bacteria are Lactobacillus convert sugars/carbohydrates into lactic acid through anaerobic Fermentation. Lactobacillus have a symbiotic/ mutualistic relationship with human , human provides them with food and shelter and in turn they protect human gut from pathogen.Question 1: Independant variable is the pathogen that is added to the petridish (i.e. Listeria monocytogenes or Salmonella or Escherechia coli) Question 2: Dependant variable is the growth of the LAB bacterial strains having antimicrobial activities (i.e. Lactobacillus plantarum or Pediococcus acidilactici or Pediococcus pentosaceus) Question 3: A control for this experiment would be addition of three petridish having the three pathogens but no LAB bacterial strains i.e. no antimicrobial agent. This can act as a negative control and tell us what we should expect if the LAB strains do not have antimicrobial activity. Question 4: Listeria monocytogenes grows best in the temperature range of 1 to 45 degree celsius with optimal growth seen somewhere between 30 to 37 degree celsius. Listeria monocytogenes is a Mesophile i.e. it is an organism that grows best in a moderate range of temperature (the temperature should neither be too hot nor too cold). Question 5: Lactobacillus plantarum grows best in the pH range of 4 to 8 with optimal growth seen at the pH of 6. Lactobacillus plantarum is an acidophile i.e. it is an organism that grows best in the acidic environment (low pH value).