Microbes in insect gut significantly influence host physiology. While Lepidoptera is a diverse insect order, the relationship between microbial symbiosis and host development remains elusive, especially concerning role of gut-colonizing bacteria in metamorphosis. We investigated the gut microbial diversity in Galleria mellonella throughout its life cycle using 16S rRNA amplicon sequencing. Our findings revealed a predominance of Enterococcus spp. in larvae and Enterobacter spp. in pupae. Remarkably, removing Enterococcus spp. hastened the larval-to-pupal transition. Transcriptome analysis showed an upregulation of immune response genes in pupae and hormone genes in larvae. Notably, the production of antimicrobial peptides in the host gut varied with developmental stages. Some of these peptides suppressed the growth of Enterococcus innesii, a dominant gut bacterium in G. mellonella larvae. This research underscores the pivotal role of gut microbiota shifts in metamorphosis, driven by the secretion of antimicrobial peptides in the G. mellonella digestive system.

Radish (Raphanus sativus L.) is a species of the Brassicaceae family and an important root vegetable crop, produced worldwide. A total of 82 radish accessions with various morphological and physiological characteristics analyzed for total sugars content. These accessions includes five subspecies and classified as wild, wild-relative, traditional and improved cultivar. The four sugars, glucose, fructose, sucrose and maltose, showed various contents in 82 accessions. Total sugar content ranged from 5.64 to 46.68 ㎎/g and showed average 25.33 ㎎/g. Total sugar content was not statistically significant among the five subspecies, but individual sugar ratio varied. The wild, wild-relatives and traditional cultivars were not significantly among average total sugars content compared with improved cultivars. On the other hand, the wild and traditional cultivars were showed high ratio of individual sugars. These results could be valuable information for the development of new radish cultivars and regulation of sugars biosynthesis in radish.