Adansonia digitata L. (baobab) fruit is commonly found throughout Africa and India, with medicinal properties, such as the ability to help control glycaemic levels. With a lack of studies published in the literature to confirm the functional properties of baobab, researchers from Portugal analysed the glycaemic effect, bioactive compounds and antioxidant activity of baobab aqueous extract (DOI: https://doi.org/10.3390/nu14020398).
In this randomised, blinded clinical trial, 31 participants—aged 18 to 40 years old—were separated into a control (n = 16; 9 female and 7 male) and intervention (n = 15; 12 female and 3 male) groups. Before receiving the intervention supplementation, participants fasted for a period of eight to ten hours. Those in the control group carried out an oral glucose tolerance test (OGTT), and the intervention group also received OGTT plus 250 mL of aqueous baobab extract.
For the aqueous baobab extract, baobab fruit from Angola was cooked and boiled in water for 5 mins. Once cooled to room temperature, researchers moved the solution to the fridge for about eight hours; researchers then sieved the solution. They noted, "The final concentration of the aqueous extract obtained, for both clinical trial and chemical analysis, was 0.1333 g Adansonia digitata L. (AD)/mL extract fresh weight (FW).” The control OGTT solution contained 75 g of anhydrous oral glucose in 200 mL of water. For the intervention group, participants’ blood glucose was measured 30 mins, 60 mins, 90 mins, and 120 mins post baobab aqueous extract ingestion.
When looking at how baobab extract affected postprandial glycemia, researchers found no significant differences among groups at 0 mins post-intervention, and they couldn't conclude from the results differences in postprandial blood glucose over time. They noted a small decrease in capillary blood glucose levels following baobab supplementation. Further, maximum glucose concentration and capillary blood glucose level incremental under the curve were much lower in the baobab intervention group, “suggesting a promising effect of baobab ingestion on blood glucose control in healthy subjects”—researchers added.
When looking at baobab composition and antioxidant properties, researchers found high levels of phenolic compounds, proanthocyanidins and hydrolysable tannins.
Though showing promising results for the functional properties of baobab fruits, the current study has some limitations, including sample size, female to male ratio, the effect and evaluation baobab extract has on the plasma-glucagon-like peptide (GLP-1) and insulin levels, or for example, the impact of baobab extract with the combination of other daily meal intake or over a longer period: days, weeks or months.
Researchers concluded: “The present study revealed that Adansonia digitata L. (baobab) fruit extract ingestion by healthy adults significantly reduces glycemia incremental AUC, as well as revealed its possessing a considerably antioxidant activity and inhibition capacity of reactive oxygen species. Therefore, the present results encourage the use of this food component as a promising source of natural antioxidants and a hypoglycaemic agent under glucose load acute conditions.”