1. MINI PROJECT: MICROBIOLOGY TITLE: EFFECT OF TIME OF MICROORGANISMS TO GROW AFTER THE FOOD DROPPED ON THE FLOOR

2. THE EFFECT OF TIME FOR MICROORGANISMS TO GROW AFTER THE FOOD DROPPED ON THE FLOOR NAME: ERIC TING CHUN WEI (15UHF06380) FOONG LI MIN (15UHF03652) WONG YEE PING (15UHF03890)

3. INTRODUCTION

4. Five seconds rule is a rule that food are allowed to eat if the food dropped on the floor less than 5 seconds. Jillian Clark founder of ‘5 seconds rule’ awarded an Ig Nobel prize in 2004 at Harvard University (Thibault, 2004)

5. Types of food Time taken for the food placed on the floor Types of the floor surface Dryness of the food These condition will affect the amount of bacteria collected from the floor

6. 87% of surveyed people stated that they would eat fallen food 55% of them are females 81% of the ladies would eat fallen food according to the 5 seconds rule Anthony Hilton, Professor of Microbiology at Aston University and his students carried out a survey and found that (Hilton, 2014)

7. Bacteria that found on the floor Escherichia coli (E. coli) Staphylococcus aureus Streptococcus Salmonella typhimurium High risk of getting food poisoning and diarrhea

8. Images of bacteria under microscope

9. Gram negative bacteria: Escherichia coli Salmonella typhimurium bacteria under scanning electron microscope (SEM) Gram positive bacteria: Staphyloccocus aureus Image of Staphyloccocus aureus under scanning electron microscope (SEM) Image of Escherichia coli under scanning electron microscope (SEM)

10. Hypothesis : The longer the duration of time the white bread dropped on the floor, the higher the amount of microorganisms on the white bread Objective : To determine the amount of microorganism found on the bread at different duration of time

11. Manipulated variable: Time of bread dropped on the floor Responding variable: Amount of microorganism grow on the bread Fixed variable: Types of food used, Environment condition

12. APPARATUS

13. MICROSCOPE INOCULATING LOOP GLASS SLIDE BOILING TUBE PETRI DISH STOPWATCH BUNSEN BURNER INCUBATOR

14. MATERIALS

15. BREAD DISTILLED WATER METHYLENE BLUE NUTRIENT AGAR

16. PROCEDURES

17. Put one piece of fresh, untouched bread under a glass slide and view using a microscope. Drop the same piece of bread on the floor for one minute.

18. Pick up the bread and place under the microscope. Observe and record the result.

19. The dropped bread is wiped lightly on a nutrient agar and is left for one day on the petri dish incubator. Place a loop of bacteria colony with an inoculating loop into a boiling tube of sterile distilled water to make a suspension of bacterial cells in the water.

20. Place a loop of this bacterial suspension on a clean slide. Allow the bacteria on the slide to air dry. Heat fixing the cells by passing through the slide quickly through the flame of a bunsen burner (2-3 times) with the glass surface exposed to the flame for 2 to 3 seconds.

21. Flood the slide with methylene blue stain for 30 seconds. Rinse the slide with distilled water, blot it dry and examine it under the microscope.

22. Record the observation. Repeat the experiment with the time of 30s, 5s and 3s.