Taking the fight to aflatoxins

At one point in his life, Rishipal Bansode, Ph.D., seemed destined for a career as a food engineer.

His university education trained him in food science — how to process and preserve foods, how to keep them shelf stable and safe to eat while maintaining their flavor and color. But along the way, Bansode became alarmed by the direction the food industry seemed to be taking, putting cheaper and more efficient processes ahead of good health and good nutrition.

Bansode worried that fellow food scientists weren’t aware of the damage their work was having on human health, and he grew concerned that health care professionals weren’t aware of changes in the food industry. Consumers, meanwhile, were demanding healthier choices: plant-based foods, natural compounds and foods made with ingredients they recognized instead of additives and preservatives they didn’t.

“The whole system seemed disjointed,” Bansode said. “I thought, let’s bring these things together and contribute in a positive way and make some impact where nutrition and food science can go along together.”

He has done just that as a research scientist at the N.C. A&T Center for Excellence in Post-Harvest Technologies, which is housed at the North Carolina Research Campus in Kannapolis. Since he joined the center in 2010, Bansode has worked to unlock the healthy secrets of peanut skins and purple sweet potatoes at the molecular level. Now he has turned his attention to eradicating a toxic mold from food and liquids that can sicken humans and their pets.

Bansode is researching aflatoxins, a family of harmful compounds produced by the common Aspergillus mold. Aflatoxins are most often found in corn, peanuts and tree nuts, which can become contaminated when crops are growing, harvested or stored. Humans and animals can be exposed to aflatoxins if they eat food products infested with mold or if they consume meat or milk from animals that have eaten contaminated feed.

Aflatoxins are a threat to public health worldwide. They’re considered carcinogens and are potentially deadly to humans and animals. In 2021, the deaths of more than 130 pets in the United States were blamed on dry dog food that contained aflatoxin concentrations that were nearly 30 times the limit set by the U.S. Food and Drug Administration. In humans, excessive exposure can cause illness, liver damage and liver cancer. Children who come in contact with aflatoxins can experience stunted growth or developmental delays.

In 2014, Bansode joined a research team based at Tennessee State University that was researching novel ways to reduce aflatoxins in whole milk. The team is led by Ankit Patras, Ph.D., an associate professor of food science and engineering at Tennessee State. The project has been funded by a U.S. Department of Agriculture grant.

This team is focused on Aflatoxin M1, a hydroxylated version of Aflatoxin B1 — the most potent of the four main types of aflatoxins — commonly found in whole milk.

Liquid food products are typically treated with heat to remove harmful substances. Aflatoxins, however, generally resist heat. The Tennessee State team wanted to see if it could degrade aflatoxins in water and then in whole milk by using light-emitting diodes to apply ultraviolet light. Apple juice and apple cider are commonly treated with UV light.

There was one problem: Milk is opaque, and UV rays can’t get deep enough into a vat of whole milk to degrade all the toxins. So the Tennessee State researchers engineered a process that directed the milk into a thin stream and applied a specific wavelength of UV light (UV-A) that could reduce aflatoxins below limits set by the regulatory agencies.

Bansode, a co-principal investigator on this project, is conducting a series of experiments involving UV-treated milk. So far, he said, the results have been promising. In vitro studies using human hematoma cells found no signs of aflatoxins, and in vivo studies using animal models found significant decreases in aflatoxin levels in urine samples. Studies of tissue and blood samples are still to come.

“We’re talking about food safety and public health,” Bansode said. “We are trying to come up with a process where we can reduce toxic levels in food products.”

A lifetime of work led Bansode to this research on aflatoxins.

Bansode grew up in India around agriculture. His father worked for a government ministry that exported agricultural products grown in tribal areas. When it was time for Bansode to go to college, his father recommended a new program at the local university: food technology, which applied chemical engineering principles to food production.

“My dad told me, ‘I have been based in this field for 10 or 15 years. I know the potential. Go for it,’ ” Bansode recalled. “I took it.”

After Bansode earned his degree, he worked for a couple of years in the food industry in India before coming to the United States for graduate school. He earned master’s and doctoral degrees in food science at Louisiana State University and did postdoctoral research at The Ohio State University Wexner Medical Center.

During his 12 years in North Carolina, Bansode has focused many of his research efforts on phytochemicals found in fruits, vegetables and grains. Plants produce these compounds to ward off bacteria, viruses and fungi. But recent research suggests that phytochemicals —beta-carotene in carrots and resveratrol in red wine, for instance — can improve immune health, reduce inflammation and prevent cancer and other chronic diseases.

In one ongoing project, Bansode is investigating whether certain chemical compounds found in purple sweet potatoes might help regulate blood-sugar levels in people with diabetes. Grown in North Carolina, purple sweet potatoes are rich in antioxidants known as anthocyanins that mimic the effects of a drug given to treat diabetes. Bansode’s research has found how anthocyanins work at the cellular level to regulate glucose.

For the past eight years, Bansode has worked with North Carolina State University researchers on ways to lessen the life-threatening reactions some people have to peanuts. By using animal models and cell culture techniques, Bansode, Leonard L. Williams, Ph.D., director of A&T’s post-harvest technologies center, and researchers from other universities have identified ways to bind a chemical compound known as proanthocyanidin with peanut allergens in peanut flour and reduce the allergic response. Bansode had previously researched the effects of proanthocyanidins, a chemical compound extracted from peanut skins that has shown promise for preventing cardiovascular disease.

Bansode said he was brought into the research team working with aflatoxins because of his background, which includes traditional disciplines such as biochemistry and molecular biology as well as nutrigenomics — how genes and nutrition interact.

Bansode didn’t know Patras before he joined Patras’ research team but suspects a colleague he worked with at some point during his career recommended him.

“I never say no,” Bansode said. “As a government servant, especially when there is a chance for collaborative work, and it’s taking you in directions where you can work things out and learn something – I am up for it.”

Preventing disease and improving human health are important issues, Bansode said, and this project lets him play a role in this fight.

“With any toxin, if we can reduce exposure to the public, that’s one step in the right direction,” he said. “The consequences with Aflatoxin B1 being a carcinogen — it has a huge impact on society.”