Students and biology professor aim to rid compost of deadly bacteria

A group of Randolph researchers hope to save lives by fighting bad cheese bacteria with good cheese bacteria.

The bad cheese microorganism is Listeria monocytogenes, which is dangerous and potentially deadly to the elderly, children, and pregnant women, and is sometimes found in soft cheeses. The good cheese bacterium is Lactococcus lactis, which is used to make cheddar cheese. They are studying whether putting Lactococcus lactis in compost will kill any Listeria and make the fertilizer safer to use.

Meron Demeki ’15 probes the temperature of compost.

“Municipalities and commercial entities are starting to get into mass composting,” said Adam Houlihan, a Randolph College biology professor. “If that compost becomes contaminated with some sort of food-born pathogens, those could possibly contaminate produce grown with the compost.” That contamination could result in more illness and death.

Houlihan asked Elizabeth Delery ’14 and Meron Demeke ’15 to work with him on this research project.

They turned four trash cans into composting bins and filled each with compost. One bin contains only the compost, while another contains the compost and Listeria (although a non-deadly form). The other two contain compost, Listeria, and different forms of Lactococcus lactis. Their theory is that the lactic acid and nicin produced by the Lactococcus lactis will help kill the Listeria.

Each day, the research team takes the temperature of each batch of compost. They also take samples to test for acidity and bacteria levels. Within a couple of weeks, the data should show hints about the validity of their theory, but Houlihan said the research will continue throughout the summer.

Elizabeth Delery ’14 prepares to streak a petri dish.

Delery has already started another research project with Houlihan to investigate a cancer treatment idea that she had. She said the compost research has helped her to develop laboratory skills that would be useful in her desired career as a medical doctor or in other careers she may choose. “I enjoy the research and the hands-on experience with lab techniques,” she said.

Demeke, who is weighing the options of attending medical school or pursuing a Ph.D., looks forward to finding out whether their method of killing Listeria works. “If we succeed in what we’re doing, we’ll be saving lives, which is the ultimate goal,” she said.

Randolph students teach science at local elementary school

A group of fifth graders leaned over their tables and listened to Treasa Bryant ’13. She held up one of the petri dishes the students had started experimenting with the day before and pointed out how bacteria had grown on the dish overnight.

Maddy Carmain ’13 teaches fifth-grade students about micro-
organisms at Dearington Elementary School in Lynchburg.

“Are they eating now?” one student asked.

“Yes, they are eating now, like this,” Bryant said, drawing smiles from the students by mimicking chomping sounds.

In another classroom a few feet away, another elementary student asked Maddy Carmain ’13 numerous questions about microbiology. “What was the first bacteria on earth?” he asked.

“I don’t think scientists know,” Carmain answered.

Fifth graders at Dearington Elementary School in Lynchburg learned about the microscopic world last week with the help of Randolph College students like Bryant and Carmain.

“I saw some natural-born teachers emerge,” said Lisa Stewart, a teacher at Dearington. “My kids have understood everything they said, and every student is engaged.”

Adam Houlihan, a Randolph biology professor, brings his microbiology students to the school once each year. On the first day, the Randolph students taught the fifth graders about bacteria and showed them how to collect bacterial samples from their environment. On the second day of the project, the students analyzed the amount of bacteria that had grown.

Sergio Rodriguez ’14 points out bacteria for a Dearington Elementary student.

The hands-on lesson helped the elementary students picture themselves working in science later on. “We had one student yesterday saying, ‘This makes me want to be a doctor,’” said Tawanda Johnson ’90, an alumna who now teaches science at Dearington.

Johnson was happy to see Randolph students helping younger students gain an interest in science. “Randolph was where I first got motivated to go into science,” Johnson said. “It’s good to see them still sending scientists out into the field.”

The annual project was featured on a news segment by WSET, a Lynchburg-based ABC Affiliate, Monday morning. Watch the report here: http://www.wset.com/story/20302622/college-students-teach-fifth-graders-about-germs

For more pictures of the project, browse this Facebook photo album.