ANTIMICROBIAL PROPERTIES OF VARIOUS GREEN TEA PRODUCTS WITH AND WITHOUT THE ADDITION OF SUGAR T3 Members: Samantha Acevedo, Conan Chen, Ethan France, Brian Goldspiel, Anna Kim, Amanda Li, Florence Ma, Sana Siddiqui, Stephanie Tarlowe, Anthony Yakely, Leanna Zhan Advisor: Mrs. Rachel Sandler Assistant: Gillian Bradley

What is Green Tea? Camellia sinensis plant leaves Fermentation Types Green, oolong, and black teas Types Matcha: powdered leaves Sencha: Uji leaves Loose: dried leaves Bagged: filtered tea bag Bottled: Snapple ® brand Instant: powdered mix http://www.plantoftheweek.org/week046.shtml 

Chemical Composition http://www.nature.com/onc/journal/v25/n13/fig_tab/1209227f1.html

Streptococcus mutans Gram-positive bacteria produce lactic acid http://en.wikipedia.org/wiki/File:Streptococcus_mutans_Gram.jpg Gram-positive bacteria produce lactic acid Breaks down tooth enamel Causes cavities and bad breath Unique genes serve as drug targets

Health Benefits Multiple studies have been conducted LDL Obesity Diabetes Cancer Dental Health Antimicrobial properties due to low degree of fermentation May destroy catechins http://www.bostonteacampaign.com/en-us/7_5/encyclopedia-of-tea.html

HYPOTHESES http://www.bitemarket.com/store/index.php?main_page=product_info&cPath=1_40&products_id=237 http://awesomebeautysupply.com/diet-snapple-singles-to-go-antioxidants-green-tea/

Preparation of Teas 240 mL boiled, deionized water Cooled to 90° Steep 15 minutes 15 g sugar per sample Diet Snapple ® On-the-Go powder

Process of Diffusion Cover plates with bacterial lawn None on control Soak disks 5 minutes Place on plate Incubate ~48 hours at 37° C Measure zones of inhibition

In Vitro Procedure Sterilize loop Inoculate and make line on plate Submerge loop in liquid 2 minutes 10 second intervals 5 in liquid, 5 in air Stir gently Scope ® 30 seconds Constant agitation Swab loop and make line on plate

Paper Disk Diffusion: Zone of Inhibition Scope ® mouthwash 1.77 cm diameter Antimicrobial compounds Alcohol Poloaxamer Polysorbate Sodium benzoate No observable zone of inhibition around disks of any teas

Paper Disk Diffusion: Possible Errors Contaminated plates Open disks exposed to fungus in lab Lapses in aseptic technique Excess liquid on disks

Paper Disk Diffusion: Zone of Growth Lipton ® tea with sugar 0.95 cm diameter No growth on control Sugar may have boosted Inconclusive Gram stain More research needed

In Vitro: Results Control had more bacteria before than after All results compared to control Less bacteria not necessarily significant Sugar appeared to have no effect Control (Water) Matcha with Sugar

In Vitro: Best Results Loose Leaves Scope ®

In Vitro: Results Discussion More subjective and qualitative Visual observation Little clear evidence of antimicrobial benefits against S. mutans Loose tea leaves had strongest effect

In Vitro: Alternate Method for Scope ® Known antibacterial agent Loop immersed in Scope ® for 30 seconds Simulated difference between rinsing with mouthwash and sipping a beverage May have attributed to differing results

In Vitro: Errors Preparation method Small sample size Discrepancies

Future Research Different preparation methods Potency of green tea on other microbes Chemical compositions of teas Loose leaf tea (in vitro) Effects of sugar Modeled after realistic experience Different concentrations

Conclusions Scope ® is most effective Loose sencha leaves (in vitro) Sugar inconclusive Possibly detrimental in one case

Acknowledgements John and Laura Overdeck The Crimmins Family Charitable Foundation NJGSS Alumni and Parents (1984-2011) Bristol-Myers Squibb Roche Kinder Morgan Bain Capital GlaxoSmithKline Novartis Bayer HealthCare Dr. Miyamoto, Dr. Surace, Dr. Quinn, Myrna Papier, Mrs. Sandler, Gillian Bradley

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