Effects of bleach powder on the midgut digestive enzymes of silkworms
Author of the article:LI Chang1** ZHOU Yi1** ZHANG Yu-Qin1 CHEN Lin1 YANG Ren-Kui2*** FENG Li-Chun1***
Author's Workplace:1. Key Laboratory of Sericulture Biology and Genetic Breeding in Ministry of Agriculture and Rural Science, College of Biotechnology, Southwest University, Chongqing 400716, China; 2. Sericulture Science and Technology Research Institute, Chongqing 400700, China
Key Words: bleaching powder; silkworm; midgut; enzyme producing bacteria
Abstract:
[Objectives] To
investigate the effect of bleach powder on silkworm intestinal bacteria and
digestive enzymes, [Methods] Silkworms were either fed mulberry leaves that
had been disinfected with bleach powder or untreated mulberry leaves, and their intestinal bacteria were
isolated and identified by 16S rDNA sequencing. [Results] The overall amount of bacteria, and of enzyme-producing bacteria,in the
midgut was generally inhibited by bleach powder, regardless of the effective chlorine concentration although
there was a positive correlation between the strength of this inhibitory effect
and chlorine concentration, Compared
to the Control, the abundance of
amylase-producing bacteria, as
well as the average production of protease, were significantly lower in larvae that had been fed leaves
treated with bleach powder, With
the exception of the the lowest effective chlorine concentration, 0.3%, exposure to all other concentrations of bleach powder
reduced the diversity of mid-gut bacteria to a single genus; Staphylococcus sp., In
contrast, the control group
and the 0.3% treatment group had relatively diverse enzyme-producing bacteria, including Staphylococcus sp., Lelliottia sp., and Buttiauxella sp. [Conclusion] Both intestinal bacterial community diversity
and bacterial digestive enzymes werre significantly inhibited by bleach powder, particularly bacterial protease
production and the abundance of amylase-producing bacteria.