Impact of photoperiod on circadian trehalose and trehalase rhythms in the digestive system of silkworm, Bombyx mori

Abstract

Circadian trehalose and trehalase rhythms were studied in the digestive system of Bombyx mori under 12 hr light-dark cycle (LD), continuous light (LL) and continuous dark (DD). The rhythmic changes were interpreted as synthetic cycles in gut wall and release cycles in gut lumen. The trehalose rhythm of gut wall comprised 8 trehalose synthetic cycles (TS cycles) under LD and LL and 7 under DD. The 24 hr trehalose rhythm of LD and LL was clock shifted to 27.2 hr under DD. The trehalose rhythm included 4 TR cycles under LD, 5 under LL and DD in the gut lumen and the 24 hr rhythm of LD was clock shifted to 19.2 hr under LL and DD. In the gut wall trehalase rhythm maintained 8 trehalase enzyme synthetic cycles (TES cycles) under LD, 10 LL and 7 under DD and the 24 hr rhythm of LD was clock shifted to 19.2 hr under LL and 27.2 hr under DD. In the gut lumen it included 4 TER cycles under LD and DD, 5 under LL and its 24-hr rhythm was advanced to 19.2 hr. Further analysis of data showed that LD favours trehalose synthesis, while LL and DD favour trehalase synthesis.

Effect of spirulina fortification on the digestive protease, carbohydrases and cocoons economic traits of mulberry silkworm Bombyx mori

“…A group of carbohyrases and their activations are controlled by different factors; the silkworm gut does not have the potential for all carbohydrases, and the microbial community existing in it will synthesize, release, and act on the complex carbohydrates. (Jenner, 1982;Strobl et al, 1998;Bhuvaneswari et al, 2012b). The results show that the amylase activity has been modulated by the supplementation of spirulina.…”

“…The treatment T3 has shown the highest percentage difference (PD) value of 15.81% with respect to T1 (control), followed by PD values of 7.51% by T4 and 3.95% by T2 (Figure 3). Since the gut content is the biochemical reactor for the digestive biochemical reaction and the site for digestion, the higher possibilities of protein release from food have been pinpointed (Bhuvaneswari et al, 2012a). In addition, spirulina (for human consumption) supplementation geared up the protein level slightly in the gut wall and at the highest rate in the gut content.…”

“…Because of the high ingestion of mulberry and sucrose accumulation, this clearly shows that spirulina has an effective role in the elevation of sucrase activity. Cellulose is a chief dietary carbohydrate, a linear polymer of D-glucose residues; the primary structural component of plant cells is digested by a series of enzymes known as cellulases in the digestive system of the silkworm Bombyx mori (Bhuvaneswari et al, 2015). Interestingly, cellulasesynthesising genes were not found in the organism; its digestion is aided by the symbiotic microbial flora present in it (Anand et al, 2010;Shi et al, 2011).…”

“…Bhuvaneswari et al (2015),Thirupathaiah et al (2018) andAnand et al (2010) are well documented the functional role of gut microbes and their impact on carbohydrate digestion. The mutualism of gut microbes further enhances the digestive function of silkworms.…”