Prebiotic potential of melon (Cucumis melo L.) and watermelon (Citrullus lanatus) shell flours

A potential alternative way of using agricultural waste such as melon and watermelon shells is its use as a prebiotic ingredient, which may improve the production of beneficial metabolites during microbial fermentation in the intestinal section of the host, through probiotic bacteria. The objective of this study wasto evaluate the prebiotic potential of melon and watermelon, which were subjected to an in vitro digestion process and subsequently analyzed by scanning electron microscope. The digest was used as a source of carbohydrates during fermentation by 3 probiotic bacteria (Lactobacillus brevis, L. paracasei, and L. rhamnosus) at 24 and 48 h, evaluating bacterial growth, carbohydrate consumption and the production of short-chain fatty acids (acetic, propionic and butyric acids). Results indicated a degradation of melon and watermelon shells after the digestion process, likewise, the growth of lactic acid bacteria was observed using melon and watermelon shells as a source of carbohydrates.These compounds were significantly reduced at 24 and 48 h. Finally, at 48 h, a higher content of short-chain fatty acids was present with a concentration of 922.31 μmol/L of acetic acid with L. brevis and melon shell, 27.6 μmol/L of propionic acid with L. rhamnosus and melon shell, and 4.96 x10⁻¹³ μmol/L of butyric acid with L. rhamnosus with melon and watermelon shells, which suggests that these types of shells have prebiotic potential.