Preservative transcriptome

Silkworm pupae are recognized as a novel, nutritionally valuable bioresource. Silkworm rearing with an artificial diet can be achieved throughout the year to ensure extensive pupa production. However, artificial diets are prone to spoilage caused by bacterial contamination. Here, we evaluated the antiseptic effect of ethylparaben (EP, a chemical synthetic preservative) and medium-chain fatty acids (MCFAs, from natural sources) in the artificial diet. Results showed that both preservatives effectively inhibited pathogenic bacterial growth. Furthermore, the addition of EP or MCFAs did not exert a negative impact on the homeostasis of gut microbiota. However, the expression of genes related to detoxification such as Ugt2 and immune-related genes Cecropin B was up-regulated in silkworms after EP consumption. Therefore, as a natural preservative, MCFAs emerge as a suitable option from a safety perspective. These findings offer valuable direction for improving silkworm artificial diet formulas in the future.