Abstract
The banana is one of the most cultivated and consumed fruits in the world. Among its many varieties, the cultivar Musa cavendish and Musa paradisiaca are among the most widespread. Despite this status, the scientific literature on the nutritional and health effects is very limited. However, the available data indicate an interesting health potential, in particular on metabolic drifts related to lifestyle changes such as oxidative stress, inflammation, obesity, hypertension, associated with their complications. The objective of our research was to evaluate the health effects of Guinea bananas (Cavendish and plantain) in relation to the type of dry extract obtained by freeze-drying, grinding, delipidation and maceration in a mixed solvent (water, alcohol and acid). After obtaining the dry extract of the two bananas, we proceeded to the determination of total polyphenols (TPC) by the Folin Ciocalteu reagent. The antioxidant capacity was evaluated by combining the following methods: DPPH, ORAC and Mito-tracker. The anti-inflammatory activity of the hydroalcoholic dry extracts was evaluated in vitro on a model of inflammatory macrophages by the NO (Nitric Oxide) assay.The TPC (Total Polyphenol Content) assay revealed that banana peels contain slightly more polyphenols than the pulp. This would be well related to the biological activities of banana as well as various tropical fruits.At 1 mg/ml, all extracts showed moderate antioxidant activity with a slightly higher antioxidant potential in banana peel extracts (cavendish and plantain). The Mitosox red method has indeed proven that bananas from Guinea protect mitochondrial membranes against ROS in a moderate way.Evaluation of anti-inflammatory capacity proved that our Guinea banana extracts (cavendish and plantain) did not produce any anti-inflammatory effect at the different doses tested (100 µg/ml, 50 µg/ml and 25 µg/ml) with 4 h pretreatment and during 24 h of LPS/IFNγ stimulation. On the other hand, hydroalcoholic extracts of the pulps gave an anti-inflammatory effect at all of the above doses, although this remained moderate. NO inhibition was observed as the dose of banana dry extract was increased.This preliminary study proves that Guinea bananas have an unexploited antioxidant potential and an anti-inflammatory capacity of the pulps correlated to the test dose. Furthermore, it also demonstrates that Guinea banana peel would not have any anti-inflammatory effect at 25, 50 and 100 µg/ml.Key words: Banana, biological activities