Bacterial challenge-associated metabolic phenotypes in Hermetia illucens defining nutritional and functional benefits

Abstract

Black soldier fly (BSF, Hermetia illucens) is popular for its applications in animal feed, waste management and antimicrobial peptide source. The major advantages of BSF larva include their robust immune system and high nutritional content that can be further developed into more potential agricultural and medical applications. Several strategies are now being developed to exploit their fullest capabilities and one of these is the immunity modulation using bacterial challenges. The mechanism underlying metabolic responses of BSF to different bacteria has, however, remained unclear. In the current study, entometabolomics was employed to investigate the metabolic phenoconversion in response to either Escherichia coli, Staphylococcus aureus, or combined challenges in BSF larva. We have, thus far, characterised 37 metabolites in BSF larva challenged with different bacteria with the major biochemical groups consisting of amino acids, organic acids, and sugars. The distinct defense mechanism-specific metabolic phenotypes were clearly observed. The combined challenge contributed to the most significant metabolic phenoconversion in BSF larva with the dominant metabolic phenotypes induced by S. aureus. Our study suggested that the accumulation of energy-related metabolites provided by amino acid catabolism is the principal metabolic pathway regulating the defense mechanism. Therefore, combined challenge is strongly recommended for raising BSF immunity as it remarkably triggered amino acid metabolisms including arginine and proline metabolism and alanine, aspartate and glutamate metabolism along with purine metabolism and pyruvate metabolism that potentially result in the production of various nutritional and functional metabolites.

Genotype-by-Diet Interactions for Larval Performance and Body Composition Traits in the Black Soldier Fly, Hermetia illucens

“…Immune counter-defences, not only in insects, are generally considered costly and governed by trade-offs [ 114 , 120 , 121 , 122 ]. The BSF possesses a remarkable repertoire of immune genes [ 52 ], permitting complex response cascades [ 114 , 123 , 124 ], among which antimicrobial peptides are of transdisciplinary interest [ 6 , 125 ]. The latter were indeed previously shown to be alternatively expressed on different diets, including upregulation on protein and lipid-rich feed [ 126 ].…”

1H NMR metabolic profiling of Staphylococcus pseudintermedius isolated from canine uroliths

“…Then, the mixture was centrifuged at 12,000 rpm at 4°C for 19 min and 580 μL of supernatant was transferred into a NMR tube with 5 mm diameter for metabolic profiling. 1 H NMR spectra were acquired using a 400 MHz NMR spectrometer (Bruker, USA) with CryoProbe Prodigy and the Carr−Purcell−Meiboom−Gill (CPMG) pulse sequence [RD−90˚−(τ−180˚−τ)n−acquisition] was applied to analyze the AU samples at 310 K in 64 scans [ 10 ].…”