Abstract
<title>Abstract</title> <p>Hermetia illucens larvae are increasingly recognized as a promising bioconversion platform for transforming diverse organic substrates into lipid-rich biomass suitable for biodiesel production. In this study, newly hatched larvae were reared for 30 days on wheat bran, vegetable leftovers, and restaurant waste to evaluate substrate effects on larval performance and biodiesel-related lipid production. Larval survival, biomass accumulation, lipid yield, and fatty acid methyl ester (FAME) composition were determined following acid/base transesterification. Larvae fed with restaurant waste exhibited significantly higher fresh (0.085 g) and dry (0.021 g) biomass and the highest survival rate compared with other treatments (P < 0.01). Lipid extraction from 10 g of dried larval biomass yielded 6.5 g and 4.5 g of biodiesel from the restaurant waste and vegetable leftover treatments, respectively, while lipid recovery from wheat bran-fed larvae was insufficient for biodiesel production. GC/MS analysis revealed 17 and 10 FAMEs in larvae reared on restaurant waste and vegetable leftovers, respectively, with dodecanoic acid methyl ester as the predominant component, followed by hexadecanoic acid methyl ester. Overall, the results indicate that both vegetable leftovers and restaurant waste are suitable substrates for biodiesel production via H. illucens larvae; however, restaurant waste offers superior larval growth performance and lipid yield, supporting its technical feasibility as a scalable feedstock for biodiesel-oriented bioconversion processes.</p>