The study provides insights into the detoxification mechanisms employed by Spodoptera littoralis to counteract glucosinolate-derived isothiocyanates (ITCs) from Brassicales plants. The findings demonstrate the versatility of glutathione-S-transferases (GSTs) in metabolizing a diverse range of ITCs, highlighting the biochemical flexibility of this generalist herbivore. The evidence that multiple GSTs exhibit broad substrate specificity and are constitutively expressed across various larval tissues supports the hypothesis that this detoxification system facilitates dietary adaptation. Moreover, the observed relationship between GST activity and larval performance underscores the ecological relevance of this mechanism in overcoming plant chemical defenses.