Bran-Derived Hydrogels Show Potential for Targeted Oral Drug Delivery to the Colon

Researchers at KTH Royal Institute of Technology in Sweden are investigating plant-based hydrogels derived from wheat and rye bran as a potential platform for delivering therapeutic compounds to the colon. As News-Medical reports, the research focuses on hydrogels made from arabinoxylan, a dietary fiber found in cereal bran. The material is being evaluated for its ability to encapsulate and release small-molecule compounds and proteins in response to enzymes produced by bacteria in the gut. The approach could eventually support oral delivery of medicines targeting gastrointestinal conditions, including ulcerative colitis, Crohn’s disease and colorectal cancer.

Unlike conventional oral drug coatings, which are generally designed to dissolve when they encounter a specific pH level, the bran-based system relies on enzymatic activity in the colon to trigger drug release. Specifically, the researchers are examining the role of β-xylanase, an enzyme produced by certain gut bacteria that breaks down plant fibers. When exposed to the enzyme, the arabinoxylan hydrogel network degrades, potentially allowing its encapsulated therapeutic payload to be released at the intended site.

In laboratory testing, hydrogels formulated from rye-derived arabinoxylan demonstrated the ability to retain a model protein within the gel structure. Exposure to β-xylanase subsequently triggered the release of a substantial portion of the encapsulated protein.

The team also investigated ways to modify the physical properties of the hydrogels, including the use of freeze-drying, to better understand how formulation and processing conditions could influence their performance.

Francisco Vilaplana, director of the PLENTY research center and professor of glycoscience at KTH, says the technology could eventually have applications in oral delivery systems for medicines and probiotics intended to reach the intestine. However, further research will be necessary before the platform can be considered for therapeutic applications. One of the key unanswered questions is whether the hydrogel can remain intact during passage through the stomach and small intestine before reaching the colon. Its behavior and ability to protect an active ingredient under actual gastrointestinal conditions have not yet been established.

The findings provide an early indication that cereal-bran fibers could serve as a foundation for enzyme-responsive drug delivery materials, although additional studies will be needed to establish their stability, release characteristics and suitability for use in vivo.

For more information, visit https://www.kth.se.