Three organic solvents were used for extracting the wild plant F.  bruguieri: methanol, petroleum ether and n-butanol. One of two concentration levels of each extract (7.5 and 3.7%; 30.0 and 15.0%; 30.0 and 15.0%, respectively) was given to the newly moulted penultimate instar nymphs of the desert locust S. gregaria through the fresh food plant. The influenced transaminase activities were investigated in the haemolymph and fat body of the last instar nymphs and newly emerged adults. The affected GOT activity in haemolymph of the last instar nymphs depended on the age because F. bruguieri extracts exhibited considerable reducing effects on it in both the early- and mid-aged nymphs but promoted enzyme activity was estimated in the late-aged nymphs, irrespective of the solvent or the concentration level. On the other hand, the strongest enhancing effect of F. bruguieri on the enzyme activity in haemolymph of the newly emerged adults (173.3±35.5 vs. 85.0±17.3 U/ml of controls) was exhibited after treatment with the higher concentration level of n-butanolic extract. Also, a remarkable inducing action of F. bruguieri extracts on the GOT activity was observed in the fat body of both late-aged nymphs and newly emerged adults, regardless to the solvent or concentration level. Nymphal treatments with F. bruguieri extracts resulted in an inhibited activity of the enzyme, generally, in the fat body of early- and mid-aged nymphs.       The methanolic extract from F. bruguieri induced the GPT activity in haemolymph along the nymphal life while the petroleum ether and n-butanolic extracts induced such enzyme activity only at the mid- and late-ages of nymphs.  With regard to the newly emerged adults, F. bruguieri, unexceptionally prohibited the enzyme activity in haemolymph, irrespective of the solvent and concentration level. A promoting effect of F. bruguieri extracts on the GPT activity was exhibited in the fat body of late-aged nymphs and newly emerged adults, regardless to the solvent or concentration level.  Otherwise, the F. bruguieri extracts exhibited an inhibitory effect on the enzyme activity in the early- and mid-aged nymphs, after treatment with petroleum ether or n-butanol for.