By Allison Mudge

Professor Geoffrey Davies and research specialist Elham Ghabbour may have different backgrounds. He is a chemist with an academic background, while she brings experience in environmental science and a focus on research.

But when together in a room, their mutual respect, as well as their passion for research, is obvious.

So now, after 13 years, whether one is completing the other’s sentence or adding to it by filling in a blank, they feed off each other.

In 1984, Ghabbour began researching little-known organic substances that are now called humic acids.

The partnership began in 1993, when she came to Northeastern and presented the research to Davies.

It was some of the first research of its kind, and Northeastern has continued to be one of only a handful of places looking to make new discoveries about the substance.

“She changed my life,” Davies said of Ghabbour. “I dropped everything I was doing as soon as she showed me what she was researching.”

In a small lab on the fourth floor of Hurtig Hall, the two have gathered the largest collection of humic material in the United States.

Humic acid is a substance that acts as a retainer, filtering potentially dangerous toxins, like mercury, from water. It also acts as a buffer in soils, controlling the binding and release of toxins.

“We’d have poisoned ourselves 1,000 times over if not for this material,” said Davies, a tenured chemistry professor.

Though specific structure of humic acid remains unknown, they have been successful in determining the structure is made up of many small “building blocks.”

Humic material no longer exists in deserts because it has all been burned away, Davies said. Understanding how robust, fertile soil deteriorates into grainy, lifeless sand is key to understanding the substance, he said.

Originally, Ghabbour and Davies said the theory on humic acid was that it was made up of large, protein-like molecules. Over the last decade, thanks to much of the research at Northeastern, it has been determined that they are actually quite small and structured like a DNA double helix. The hollow helix allows the structures to better retain water. When the helix fills, it biomineralizes and turns to rock, Davies said.

“You couldn’t make a material like this if you tried,” Davies said.

Northeastern is largely considered the center of the research, Ghabbour said. She and Davies frequently take calls from interested parties, like public works departments from cities nationwide.

But they haven’t been without help.

About 40 undergraduates have assisted Davies and Ghabbour with their research since 1996. It is the largest group of undergraduate researchers at Northeastern, Ghabbour said.

“[They’ve] been great to work with,” said Brianna Kranzel, a junior behavioral neuroscience major. Kranzel, who has been involved with the research since September, said weekly meetings where student groups can catch up with one another are especially helpful.

“They are always understanding when schedules get hectic around exam time,” said Kranzel, who learned of the study through an e-mail Davies sent to former students explaining there were openings for more student researchers. “They both have a genuine interest in teaching us about their area of expertise, and that is what has made it so rewarding for me personally.”

Students usually get involved with the research through word of mouth, Davies said. Most are majoring in some type of science, though pharmacy or physical therapy majors have assisted with research as well. There is no application process to join.

Sharon Soucek heard about the opportunity for research in a class she took with Davies last semester. The sophomore biology major said she finds the research both rewarding and interesting.

There are six students working with humic acids this semester. They assist Davies and Ghabbour with the large amount of research still required for further understanding of the material.

Davis and Ghabbour mentioned how lonely the lab is during school breaks, when their workload increases, and the student researchers have gone home.

Kranzel and a group have been studying humic acid in iron derived from German peat, a type of moss, to see how it binds certain nucleotides, she said. Of the research, Kranzel said she has been able to apply general chemistry skills while learning new laboratory skills, like how to do experiments using liquid nitrogen.

“The data analysis for this project is complex,” she said. “I learned a lot about the theory behind what I was studying.”

Other students are currently studying the water hyacinth, a plant that can be found anywhere water flows, Davies said. It grows so quickly that it chokes up waterways and kills other plants. It sucks up metal in the earth, just as other humic structures do, but it sucks them up so quickly that it dominates the entire ecosystem.

With all of the mystery still surrounding humic acid, Davies and Ghabbour said they rely on their student researchers as a vital source of information.

The students who participate in the study gain research experience prior to graduate school, Ghabbour said. Several students’ names have been mentioned in published work, and in the past, the group has traveled to Brazil and Poland.

Kranzel, who hopes to attend medical school, said the research should give her an edge over others. A former lab partner’s co-op interviews were heavily centered on her experiences in the humic acid lab, she said.

Soucek said she plans to remain involved with the research.

“It’s not something you learn in classes,” she said. “It’s very in-depth. It’s what work’s like.”