Dual application of black soldier fly (Hermetia illucens): Protein-rich animal feed and biological extraction agent for polyhydroxybutyrate

ABSTRACT

Aims@#The primary aim of the present study is to evaluate the effect of rearing substrates on the nutritional content of black soldier fly larvae (BSFL) by incorporating Cupriavidus necator cells containing intracellular polyhydroxybutyrate (PHB) in BSFL diet to further increase the protein content and simultaneously to biologically extract the polymer by utilizing the digestive system of BSFL. The potential application of BSFL as a biological PHB extraction agent was determined.@*Methodology and results@#Two feeding strategies consists of a mixture of protein (P) to carbohydrate (C) with a ratio of P50C50 food waste (control feeding) and feed with bacterial cells (modified feeding). A comparison on the proximate analysis between this research and two commercially available products were conducted. Feeding BSFL with P50C50 food waste revealed the highest crude protein content of 81.3 ± 0.2%. Additional bacteria cells in the BSFL diet, however, showed a negligible decrease in crude protein content of 0.67% as compared to the control feeding. Howbeit, this results comparably higher in contrast to the commercial products, with increment of crude protein content by 12.1% and 40.8%, respectively.@*Conclusion, significance and impact of study@#Two desirable products were obtained from the feeding with cells (1) high protein content of BSFL and (2) biologically extracted polymer. This is the first study to demonstrate the utilization of BSFL as a biological extraction agent to partially extract biopolymer and increase the protein content by feeding with cells.