Mealworm larvae (Tenebrio molitor L.) exuviae as a novel prebiotic material for BALB/c mouse gut microbiota

Abstract

The objective of this study was to evaluate the effect of yellow mealworm (Tenebrio molitor L.) exuviae (ME) given as a prebiotic in 20% of the diet fed to BALB/c mice. Analysis of the ME revealed that it was mostly composed of crude protein (52.94%), crude fiber (10.70%), and moisture (10.54%). When ME was fed to mice for 8 weeks, the number of intestinal lactic acid bacteria increased, reaching similar numbers (4.50 ± 0.80 CFU/mL) to those (4.70 ± 0.80 CFU/mL) of the control group not fed ME. Microbiome analysis showed that 8 weeks feeding of ME promoted the growth of Bifidobacteriaceae and Lactobacillaceae compared to the POS group, indicating the positive effects of feeding 20% ME on the intestinal microbiota of mice. These results suggest that ME can be considered as a dietary prebiotics to improve human gut microbial population, but further application study to human is necessary.

Keywords: Bifidobacteriaceae; Exuviae; Lactic acid bacteria; Mealworm; Microbiome.

Fig. 1

The total number of bacteria counted for next-generation sequencing (NGS) and alpha- and beta-diversity analysis depending on the groups and feeding periods. (A) The total number of bacteria counted for NGS. (B) Alpha-diversity analysis. (C) Beta-diversity analysis

Fig. 2

The relative abundance of the major bacteria in BALB/c mice small intestines distinguished by groups and feeding periods. (A) Phylum level bacteria. (B) Firmicutes to Bacteroidetes ratio

Fig. 3

Relative abundance of major bacteria in BALB/c mice small intestine distinguished by groups and feeding periods. (A) Family level bacteria in the small intestine of BALB/c mice fed an experimental diet for 4 weeks (B) Family level bacteria in the small intestine of BALB/c mice fed an experimental diet for 8 weeks. AIN4: CON4, MAIN4: POS4, MIE4: MWE4, AIN8: CON8, MAIN8: POS8, MIE8: MWE8