Microbial content of Yarmuk River and King Abdulla Canal waterways in Jordan.

AIM: The aim of this study was to monitor the microbiological contamination of the water of Yarmuk River (YR) and King Abdulla Canal (KAC) in Jordan for 6 months (June-November 2000) for their aerobic plate count, total coliforms, fecal coliforms, fecal Streptococci, Staphylococcus aureus, Salmonella, fungi, algae, and protozoa. MATERIAL AND METHODS: Water samples were collected monthly for 6 months (June-November 2000) from three generally representable locations of each of YR and KAC. The procedures of Standard Methods for the Examination of Water and Waste Water were, in general, used. RESULTS: The average counts in log colony forming units/ml water were 5.4, 4.9 aerobic plate counts; 3.4, 3.5 total coliforms; 2.0, 1.9 fecal coliforms; 1.7, 1.6 S.aureus; and 1.7, 1.7 fungi (molds and yeasts), respectively. The presumptive tests for Salmonellae were positive in all samples of the two waterways. Average algae and protozoa counts during 4 months (July-October) in 5-l water samples as log/liter were 6.7, 6.9 in Yarmuk River and 3.2, 3.4 in King Abdulla Canal, respectively. The microbial contents of the sediments of the two waterways and temperature, pH, electric conductivity, turbidity, and dissolved oxygen were also recorded. CONCLUSION AND RECOMMENDATIONS: From the public point of view, the microbial water quality of the two waterways is not suitable for drinking before treatment; it is, however, suitable for agricultural restricted irrigation.

Inhibition of Bacillus cereus by Garlic Extracts.

Aqueous extract of garlic ( Allium sativum , L.) was prepared from a 1:2 (wt/vol) ratio of fresh garlic bulbs to sterilize distilled water. Garlic extracts of 3%, 5% and 10% inhibited the growth of Bacillus cereus on nutrient agar plates 31.3%, 58.2% and 100%, respectively. Extracts from garlic bulbs stored at -18°C are slightly more inhibitory to the growth of B. cereus than extracts from bulbs stored at 15-35°C for 6 months. The greatest extract activity was found when garlic bulbs were extracted and left at 30°C for 4 h before filtration. When the macerate was held at 4°C, 6 h of storage were needed for the extract to reach its greatest activity. Gamma irradiation, at the dose of 570 krads, of garlic bulbs with subsequent freezing before extraction decreased the extracts original activity up to 50%. Exposing the extracts to heat treatments of 80-90°C for a total heating time of 5 min completely destroyed the antibacterial activity of the extract.