Bacteriological and Physicochemical Screening of Some Irrigation Canals at Nile Delta, Egypt

Abstract

The present study aims to examine the water quality through several physico-chemical and bacteriological analysis. Thirty two water samples were collected from different 22 irrigation canals at Nile Delta. Some environmental parameters were monitored using AQUA meter water quality device. The temperature values varied from 14.3 to 17.6°C, pH values from 7.5 - 8.4, oxidation - reduction potential from 229.1 to 436.6 mV and specific conductivity from 76 to 820.8 µS/cm. Whereas, turbidity values ranged from 0.5 to 244.9 NTU and dissolved oxygen from 92.8 to 98.6 % Sat. One hundred isolates were selected and purified then divided into groups according to their morphological characteristics. Five distinct predominant organisms were selected and identified by 16S rRNA gene sequencing as Pseudomonas aeruginosa strain E1, Proteus mirabilis strain E2, Enterobacter cloacae strain E3, Pseudomanos otitidis strain E4 and Enterobacter canceroqenus strain E5. The total bacterial count ranged from (158 ± 32) x 105 to (0.1 ± 0.04) x 105 CFU/ml while, lactose-utilizing Gram-negative bacterial count ranged between (93 ± 7) x 103 to (0.1 ± 0.1) x 103 CFU/ml. There were positive correlations between lactose-utilizing Gram-negative bacterial count and both total bacterial count (r = 0.85) and Temperature values (r = 0.62).