Mining millets

Millets are ancient grains and cereals with origins in Africa, the Middle East and Asian countries including China and India, where they are food staples. In addition to growing in harsh environments and enduring drought or attacks by pests, millets are often less processed and yield higher nutritional benefits than grains such as corn, rice and wheat.

University of Illinois at Chicago

A bowl of little millet, one of the five grains profiled in this study, before oil and lipid extraction.

Those conventional grains of the Western diet are well studied, but scientists know little about the bioactive food species in major and minor millets, including the distribution of lipids, or fat-soluble compounds; the composition of fatty acids, or lipid building blocks; and the presence of nutraceuticals, or substances in millets and food that benefit physiological health.

Sugasini Dhavamani, a research assistant professor at the University of Illinois at Chicago, and her team have studied the nutri-lipidomic profiles of major and minor millet seeds and oils.

“I am passionate about lipid research,” Dhavamani said, “I love working at the University of Illinois because we have amazing equipment and facilities, and great means for collaboration.”

The oils of grains are not commercially available, so the researchers first extracted lipids from the millets, then analyzed samples using high-performance liquid chromatography and gas chromatography-mass spectrometry.

“The oil extraction takes time,” Dhavamani said, adding that the researchers face other challenges. “After extraction we often get a low quantity of lipids, which can also cause difficulty. Stability is a concern because the lipids are easily oxidized.”

University of Illinois at Chicago

Sugasini Dhavamani in her lab at the University of Illinois at Chicago, processing and analyzing gas chromatography–mass spectrometry data obtained from the millet seeds and oils.

After profiling sorghum millet, little millet, finger millet, proso millet, kodo millet, pearl millet and foxtail millet, Dhavamani and colleagues found that oleic acid, linoleic acid and alpha-linoleic acid, or omega-9,-6 and -3, are the three major fatty acid species present in millets and seed oils.

“Most of the millets evaluated contained omega-9 and omega-6 and a small amount of omega-3 fatty acids, which help to lower cholesterol and blood pressure levels, and can benefit chronic disease,” Dhavamani said. “Millets also have nutraceuticals, which are helpful for lowering inflammation.”

In the future, the researchers want to expand this work into animal models, where Dhavamani can assess the health benefits of millet consumption, followed by examining proteomics and metabolomics of millets; however, experiments of this scale require increased funding.