Screening for hydrolytic enzymes produced from indigenous bacterial isolates

Abstract: By screening different soil samples collected from Monofia governorate in Egypt,twelve bacterial isolates were isolated and tested against different root rot fungi namely,Aspergillus niger var. niger Tiegh., Botrytis fabae Sardiña, Fusarium oxysporum var. orthoceras,Botrytis cinerea Pers., Fusarium avenaceum, Fusarium oxysporum Schltdl., Helminthosporiumspp., Alternaria alternata (Fr.) Keissl., Fusarium solani (Mart.) Sacc., Bipolaris oryzae (S. Ito &Kurib.), Rhizoctonia solani J. G. Kühn, Pythium ultimum (Trow). Different inhibition zones anddifferent hydrolytic enzyme production obtained from these bacterial isolates. Four of themdesignated as D, F, E and G showed a high inhibition zone and a high production of differenthydrolytic enzymes identified as genera Pseudomonas (D), Bacillus (two different isolates, E andG), and Acinetobacter (F); according to biochemical testes using API Kits, and confirmed withmolecular identification using 16S rDNA. Isolate D (Pseudomonas sp.) have 96% inhibitionagainst Fusarium solani. All isolates have more or less 90% inhibition against wilt diseasescaused by different species of Fusarium. Strain E and G (Bacillus sp.) showed 88, 89% inhibitionagainst these harmful fungi. Also strain F (Acinetobacter) showed 96% inhibition againstPythium ultimum causing damping off to very economic plants. High production of severalhydrolytic enzymes like glucanase, protease, chitinase and lipase were detected by these bacterialisolates.