They show a high toxicity against Spodoptera litura larvae by inhibiting sodium channels, leading to strong paralytic activity and eventually to the death of the insect.
The anthraquinone aldehyde nordamnacanthal (1,3-dihydroxy-anthraquinone-2-al) present in G. aparine has an antifeedant activity against Spodoptera litura, the Oriental leafworm moth, a species which is considered an agricultural pest.