Effect of some medicinal plants extracts on the growth of the alga microcystis aeruginosa kuetz

الملخص EN

The aim of the present study was to investigate the effect of three aqueous extracts made from three medicinal plants; Glycyrrhiza glabra L, N'igella saliva L.and Pimpinella anisum L., in three graded concentrations as 3.5, 7.0 and 14.0 mg/ml of each extract on growth of M.aeruginosa (an alga belong to Cyanophyceae).

The study criteria included total number of alga, growth rate and growth duplication time .The design of the experiment was CRD in three replications.

Analysis of variance and the least significant difference (LSD) at 0.05% level utilized to detect treatment effects.

Results indicated that aqueous extracts had a significant effect on the study parameter of the experiment.

Extract from Glycyrrhiza glabra L inhibited the growth of the alga (M.aeruginosa ), in which highest GI(85%) was obtained at 14.0 mg/ml in 72 hours after the alga was exposed to the extract solution, while that of Gl (71%) was at 70 mg/ml, 96 hours after exposure.

Black seed (Nigella saliva L.) extract increase the growth rate of the test alga five times that of control treatment at concentration of 14.0 mg/ml and a reduction in multiplication time was noticed.

Extract of Pimpinella anisum L.

in low concentration (3.5, 7.0) enhanced growth rate of the alga while high concentration of 14.0 mg/ml reduced it.