It’s rare for a study done by undergraduates to be published in nationwide peer review journals. A team of University of Hawaii Maui College students, under lead researcher Dr. Sally V. Irwin, are now among the one percent in the country that have had a research study published.

UH Maui College students Emily Graham, Ashley Malek and Adriel Robidoux; chemistry lecturer Dr. Peter Fisher; and microbiology and genetics professor Irwin recently published their study that shows that a common food preservative can kill beneficial or “good” bacteria that is naturally found in the human gut; the type of bacteria effected are also found in fermented products that are rich in probiotics such as yogurt, kimchee and kombucha.

The researchers found that sulfites in food preservatives killed or inhibited the growth of the good bacteria when tested at levels generally regarded as safe by the FDA.

“Studies show a significant increase over the past 40 years in food allergies, obesity, and metabolic disorders that have a direct correlation to disbiosis, or changes in the microbiome,” Irwin said. “In trying to understand what in our environment may be causing this change, the use of many food preservatives and their effects on beneficial bacteria came to mind.”

Irwin, who is also an adjunct professor in the Cell and Molecular Biology department at UH Manoa John A. Burns School of Medicine (JABSOM), said overuse and misuse of antibiotics has been indicated as having a significant impact on our microbiome, but this is the first time food preservatives have been tested for their effects on beneficial bacteria.

The students were exposed to lab work and overcoming the common obstacles of research, such as learning how to ask questions and when to question the answers. “This is the best education I can give to future scientists,” Irwin said. “It has been exciting and incredibly satisfying for me and the students to present a significant piece of research that others in the scientific community can build upon.”

Irwin’s team intends to continue to study the effects of sulfites and other food preservatives in the lab and in living organisms, such as mice. “We have started some preliminary work looking at the effects of sulfites on enzymes found in human saliva and commensal mouth bacteria,” she said. “We would like to collaborate with another lab to do some mouse studies or use an artificial gut environment to look at effects on a mixture of bacteria.”

The team’s study, Sulfites inhibit the growth of four species of beneficial gut bacteria at concentrations regarded as safe for food, is published in PLOS One, a multidisciplinary open access journal available on line at Journals.plos.org/plosone/article?id=10.1371/journal.pone.0186629.

A public presentation of “The Human Microbiome in Disease and Health”, covering their research and an overview of work done by other researchers on the human microbiome, is scheduled for Wednesday, Nov. 29 at 5:30pm in UH Maui College’s ‘Ike Le‘a Building, Room 144. It’s open to the public.

Photo courtesy of UH Maui College