Distillers Grain Particles Studied in Cancer Drug Research
by Sara Eiesland
By incorporating a co-product of ethanol production, researchers at South Dakota State University (SDSU) are working to expedite and localize the delivery of drugs to cancer-infected cells.
SDSU Assistant Professor Omathanu Perumal and his team in the Department of Pharmaceutical Sciences have been working with zein – a protein found in distillers grain – to more effectively deliver medications.
Zein is unique in its ability to prevent water absorption, and is found in some common products such as chewing gum. These nanoparticles, tiny particles only visible through an electron microscope, are the medium for moving the drug through the patient’s immune system. Because these zein particles are so tiny – 500 times smaller than the diameter of a strand of human hair – they are able to treat cancer cells without affecting healthy cells in the surrounding area.
These drug-loaded zein nanoparticles are now being delivered by injection in animal experiments, but future tests may explore oral, topical, and other delivery methods.
“ As far as biomedical applications are concerned, zein is a unique protein as it is water insoluble and therefore can sustain drug release for prolonged periods,” Perumal explained. “Our main interest is to use zein as a protein biopolymer to develop nanoparticles where in the drug is encapsulated inside.”
In the technique SDSU researchers are exploring, medication is encapsulated within the zein nanoparticles and delivered to the cancer-affected cells. By experimenting with dosage and the effectiveness of the process as compared to traditional methods of delivery, the results of Perumal’s research show the treatment is meeting expectations.
Perumal’s study of these distillers grain particles has been funded by the South Dakota Corn Utilization Council, and his team’s ongoing research is supported by the South Dakota Board of Regents. The university has filed a provisional patent, and the researchers are moving forward with early pre-clinical studies using mice.
Although his team is now only working with human breast cancer cells, Perumal anticipates the possibility of expanding zein nanoparticle treatment for other conditions, such as artery blockage. For those with blockage around the heart, synthetic stents are inserted to help to keep the artery open. However, these stents often function as foreign objects in the body, sometimes causing the body to combat the stent’s existence, causing inflammation. But by coating the stent with drug-loaded zein nanoparticles, he hopes that this rejection would be prevented.
Perumal noted that zein is now commercially extracted from corn gluten meal, a byproduct of wet mill ethanol production. But, Perumal said, there are also published methods to extract zein from DDGS.
“The key is to develop an economical extraction process,” Perumal said. “In my opinion, there are tremendous opportunities for developing a cost-effective extracting procedure by using a part of the ethanol to extract zein from DDGS using combinations of ethanol with water and other solvents.”