There’s continued interest in the health benefits of acai, which marketers are calling an Amazonian ‘superfruit.’ Researchers from the University of Reading and University of Roehampton argued that its rich anthocyanin content means the fruit may reduce the risk of age related diseases.
“We hypothesize that both fiber and plant polyphenols present in açai (Euterpe oleracea) provide prebiotic and anti-genotoxic benefits in the colon,” they wrote in their report, published in the journal Food Chemistry.
This means that acai may have a prebiotic effect—which means it acts as fodder to the beneficial bacteria living in human organs along the digestive system. Fermentation that comes from the bacteria’s digestion of prebiotics in turn provide health benefits to its hosts, such as anti-inflammatory activities, as well as influencing metabolism and satiety.
As a preliminary study, the researchers looked at how intact the polyphenols of digested acai can remain throughout the digestive system by using an in vitro model.
Despite uncertainty surrounding the precise definition of fiber, demand for prebiotic ingredients is booming, according to one ingredient supplier.
Anthocyanins as a prebiotic
The researchers used acai pulp that was then freeze-dried and then ground to a powder. Then, they simulated intestinal digestion using a standardized method that mimics the human digestive system. This was done to “look at the potential bioavailability and bioactivity of acai polyphenols,” they wrote.
From the process, they found that 49.8% of the total initial polyphenols were available. “Our work demonstrates that polyphenols present in açai may be degraded during the digestion process, but importantly, that they are not fully destroyed and a significant percentage of these compounds may therefore reach the colon,” according to the report.
More in vivo studies, such as RCTs, need to be conducted so that researchers can better pinpoint what the health benefits of anthocyanins actually are.
Multiple studies have emerged in recent years to study how anthocyanin-rich fruits interact with bacteria in the gut, and whether or not this interaction offers health benefits.
Recently, a systematic review by researchers in the Federal University of Sao Paulo shed more light on the prebiotic properties of anthocyanins, stating that the chemical compound indeed feeds beneficial bacteria in the gut, potentially offering health benefits to the host.
Source: Food Chemistry
Published online ahead of print, Volume 234, 1 November 2017, Pages 190-198, https://doi.org/10.1016/j.foodchem.2017.04.164
In vitro approaches to assess the effects of açai (Euterpe oleracea) digestion on polyphenol availability and the subsequent impact on the faecal microbiota"
Authors: R. M. Alqurashi