Evaluation of the synergism of papaya and kale in their prebiotic effect in rats

Papaya fruits contain insoluble diet fibre and are used in popular medicine as a laxative, whereas kale leaves contain mainly soluble diet fibre that has beneficial effects on intestinal flora. The aim of this study is to evaluate if the concurrent administration of both vegetables to rats results in a synergism in their prebiotic effects. Four groups of rats were used: control group without treatment, and three treated groups, which received orally papaya (P), kale (K) or a mixture of both (M) (60% K and 40% P) at 130mg/rat/day. Lactobacilli and bifidobacteria (beneficial bacteria) as well as aerobic and enterobacteria (potential pathogens) counts were determined in the colonic and ceacum contents. The percentage of water was evaluated both in faeces and in intestinal contents. The administration of M significantly increased the ratio of the beneficial bacteria to potential pathogens in both intestinal segments analysed, colon (1.43±0.2 vs. 1.32±0.01; p<0.01) and ceacum (1.4±0.2 vs. 1.3±0.01; p<0.01); however this effect was not observed with each vegetable. In addition, all treatments significantly increased the percentage of water in the faeces (52.3±7.3%, 51.9±8.4% and 51.6±8.9%, K, M and K, respectively, vs. 48.5±0.8% in controls; p<0.01); whereas only the mixture significantly increased this in ceacum contents (79±12% vs. 75±0.5%; p<0.05) and colonic contents (78±12% vs. 70±2.6%; p<0.05). The combination of both vegetables facilitates the prebiotic effects showed by each one when administered separately.

Acknowledgements: Fapesp and Capes