A study published in Food Research International has found that nanoencapsulating anthocyanins can enhance their absorption in the gut, while also preventing their degradation in the digestive system.
Researchers at the São Paulo Research Foundation also found that the plant-based nutraceuticals could reach organs and tissues better than their unencapsulated counterparts, meaning they are more likely to exhibit a positive effect on a user.
Anthocyanins are a type of polyphenol extracted from blue, red and purple fruits and vegetables, and have commonly been touted for their anti-inflammatory and antioxidant capabilities.
Therefore, they are often incorporated into dietary supplements and functional foods — though their bioavailability is often affected by environmental conditions such as temperature, light and pH.
Optimising gut absorption
The gut can be an unforgiving location for sensitive nutritional compounds, owing to the action of digestive enzymes, as well as the gut microbiota.
As anthocyanins can be easily degraded, they often exhibit a limited bioavailability in their pure form, which can affect their efficacy as a nutraceutical significantly.
“Several previous studies showed that when anthocyanins are taken orally, a very small amount is absorbed and stays in the organism only for a very short time,” said Thiécla K. O. Rosales, first author of the article and a researcher in the Department of Food and Experimental Nutrition at the University of São Paulo.
To determine how best functional ingredient developers can utilise anthocyanins, researchers evaluated the use of nanotechnology in boosting anthocyanin bioavailability.
To achieve this, they extracted and purified anthocyanins from blackberries and radiolabelled them to compare the extent of degradation between nanoencapsulated and non-encapsulated iterations.
Researchers nanoencapsulated the anthocyanin molecules with both citrus peel-derived pectin and the lysozyme enzyme found in egg whites.
Nanoencapsulation significantly impacts anthocyanin bioavailability
During the study in mice, it was demonstrated that the biodistribution and bioavailability of nanoencapsulated anthocyanin was significantly higher than anthocyanin on its own.
It was also found that anthocyanins connected to a nanostructure moved through the digestive tract slowly and remained in the animal's system for a sustained period of time.
The absorption of anthocyanins was also enhanced, and targeted tissue delivery was made possible.
It was also noted that anthocyanins that didn't undergo encapsulation were excreted rapidly from the body.
The nanoparticles were also proven to be safe in both in vitro and in vivo studies, highlighting the potential of this method in dietary supplement or functional food formulations.
“We continue to contribute to this research field while developing the technology and expect to be able to publish new results soon. We’re also studying the possibility of industrial-scale production,” Fabi concluded.