Characteristics of intestinal microbiota and enzyme activities in mice fed with lily bulb

The aim was to investigate the effect of lily bulbs on the microecological characteristics of intestinal microbiota and enzyme activities in normal mice. Thirty SPF Kunming mice were randomly divided into the control group, Lilium lancifolium (LL) group and Lilium davidii var. unicolor (LDU) group. Mice of the latter two groups were given 0.15 g·mL^-1 lily bulb solution, respectively, by gavage twice a day, while the control group was given the same volume of sterilized water. After 49 days, intestinal contents and mucosa of all mice were collected and the characteristics of intestinal microbiota and enzyme activities were analyzed. Results showed that the number of Lactobacillus spp. and Bifidobacteria spp. in the LL group was significantly higher than that in the control group (t = 2.68 × 10⁷, P = 0.000; t = 5.96 × 10⁷; P = 0.000) and the LDU group (t = 6.12 × 10⁷, P = 0.000; t = 2.71 × 10⁷, P = 0.000), while the number of total bacteria was significantly lower (P = 0.040). Microbial activity in intestinal contents and mucosa of the LDU group (t = 0.43, P = 0.001; t = 0.69, P = 0.000) decreased, and microbial activity in intestinal mucosa of the LL group decreased significantly (t = 0.89, P = 0.000) but increased significantly in intestinal contents of the LL group (t = 0.81, P = 0.000). The activities of amylase (t = 455.73, P = 0.000; t = 206.56, P = 0.000) and protease (t = 52.32, P = 0.000) increased but the activities of lactase (t = 443.51, P = 0.000; t = 15.71, P = 0.000) and sucrase (t = 5.82, P = 0.000; t = 366.82, P = 0.000) decreased significantly in contents from the LL group and LDU group. Except for the sucrase activity, enzyme activities in mucosa of the LL group were completely opposite to those in contents (t = 44.15, P = 0.000; t = 1.25, P = 0.007; t = 14.64, P = 0.011). In conclusion, dietary lily bulbs increased intestinal contents amylase activities and mucosa lactase activity significantly. Lily bulbs, especially Lilium lancifolium, can promote the growth of Lactobacillus spp. and Bifidobacteria spp., and inhibit the growth of total bacteria in the intestines of normal mice. Lilium lancifolium bulbs have the potential to be a functional food.