Senior Paper: Antibiotic Efficacy of Natural Plant Substances


You are camping in Napa Valley with your buddy. You are walking through the woods, chatting about life when he stumbles over a tree root and falls. As bad luck would have it he cuts his knee on a piece of rusted scrap metal. His cut is bleeding badly. You manage to stem the flow of blood with water from your bottle, and dig in your supply kit for some antibiotics and a Band-Aid. But you forgot the Neosporin back at home! The wound looks like it needs treatment, or might get infected.

You have two options. Do you cut the camping trip short and drive back home, which is a days-ride away, during which an infection might occur anyway? Or do you attempt to find an alternative solution?

A simple poultice of garlic or ginger, plenty of which you have back at camp, will be enough to stave off infection. If you know this, chances are that you read Harriet Baayeh’s senior experimental project paper.

For her senior project, Harriet, an international student from Ghana pursuing a BSc. in Biology, decided to compare the antibiotic efficacy of natural plant substances such as ginger and garlic against established commercially-produced antibiotics such as Penicillin, Cefazolin, Ticarcillin, Cefotaxime and Tobramycin.

“The inspiration for my project was two-fold,” Harriet said when I asked how she came to work on such an interesting project. “One, I took a microbiology class last year, which is where I first got the idea for my project. Two, I come from a family big on using natural plant stuff for everything, so I was really curious to see how substances like garlic and ginger would fare against some of the more popular commercially-marketed antibiotics like Penicillin or Ticarcillin.”

Harriet worked in the lab on her project since July of last summer, conducting experiments with help and professional supervision from some Bryn Athyn College professors in charge of the biology major program: Dr. Stella Evans and Dr. Higgins – her two main supervisors, as well as additional aid from Dr. Cooper and Dr. Bryntesson.

“They were immensely helpful and generous with their time,” Harriet says of her lab partners. “I mostly had no idea where to begin or what to do, and they were there to guide me every step of the way. We figured out the solutions to problems that rose up together, and I had a lot of fun working with them. Without them I wouldn’t have gotten anything done.”

In her experiments, Harriet prepared cultures from bacterial strains such as Staph. aureus (which causes food poisoning and sinusitis), Staph. epidermidis (responsible for a lot of hospital-acquired infections) and E. coli (which can cause urinary tract infections, urinary tract infections, gastroenteritis, and food poisoning. These cultures were plated and then treated with crushed ginger and garlic extracts, as well as antimicrobial wafers made from commercial antibiotics such as Penicillin, Cefazolin, Ticarcillin, Cefotaxime and Tobramycin.

The treated cultures were then observed for a certain time period, for zones of inhibition. A zone of inhibition is region around an antibiotic which remains clear in a bacterial culture, showing the extent to which that antibiotic inhibits bacterial growth. The higher the zone of inhibition, the more effective the antibiotic is.

I asked Harriet how the natural plant substances matched up against the manufactured brands, and she was really excited with the results.

“They performed very well,” was Harriet’s response. “There wasn’t a clear winner in the Natural vs. Artificial argument, but overall the natural plant substances were generally as effective as the commercially-packaged brands.”

In spite of this stalemate, two factors really sold her on the benefits of using natural plant substances like honey and ginger over brands like Penicillin or Tobramycin.

“First ginger and garlic are a lot cheaper and easier to get – I use them all the time,” she laughed. “Garlic, cayenne pepper, tumeric, etc are all easily incorporated in the everyday diet. Secondly and more importantly, there’s the issue of acquired resistance – some bacteria gain resistance if they are treated repeatedly with the same antibiotic, or if an infected patient does not stick strictly to an antibiotic course.”

Bacterial resistance is a very serious issue as it really hinders antibiotic treatment against infections like during medical procedures like surgeries. In addition there’s a mounting worry about the use of chemical products for household cleaning, lotions, soaps, detergents, etc, when a simple solution, such as one of warm water and lemon juice is just as effective. A lot of medical and health experts insist that antibiotics should only be used when strictly necessary, otherwise natural remedies are the way to go. Most germs and bacteria do not readily acquire resistance to these natural remedies, which unlike commercial antibiotics, have the added benefit of not having any negative side effects.

Harriet left me with this parting advice – Try to use natural remedies as much as you can. They’re cheap to get and easy to use, and healthier to boot! The next time you want to use Chlorox to clean that kitchen sink, consider crushing some lemons into warm water instead – you’ll save more money that way!

Harriet Baayeh just completed her senior paper and is awaiting the grading process. She graduates in the summer of this year. Her ultimate plan, should everything work out, is to go on to medical school and eventually work with kids for a career. So far she’s an excellent experience at Bryn Athyn College – one she wouldn’t trade for anything in the world – and she’s really grateful to everyone here who has supported her in her journey thus far – her professors, lab supervisors, her friends from the school and community, and her family.


Written by Philip Gyasi, Class of 2014