Laboratory and greenhouse experiments were conducted to assess the efficacy of Eucalyptus citriodora, Ipomoea carnea, Cuminum cyminum, Allium sativum and Hyoscyamus muticus leaf extracts, and Streptomyces exfloliatus (S) and Trichoderma harzianum (T) for controlling Botrytis fabae causing chocolate spot disease of faba bean. Laboratory study supported the use of E. citriodora (Ex 1 ) and I. carnea (Ex 2) extracts than the others for controlling the growth of B. fabae. S+Twas the best for inhibiting spore germination followed by Ex 1 +Ex 2 after 8 h of testing, whereas Ex 1 +Ex 2 produced the lowest percent of germination after 16 h. After 4 days, the inhibiting order of the growth of B. fabae was S+T > Ex 1 +Ex 2 > T > Ex 2 > Ex 1 = S. Greenhouse experiments showed the highest activities of peroxidase, catalase and pectinase in the infected plants. These activities were markedly reduced in healthy plants and widely changed by the biocontrol treatments. Applying biocontrol agents to the infected plants increased minerals (N, P, K and Mg), and both Chl biosynthesis and the photosynthetic activity, which in turn led to accumulation of metabolites. This served the plant to resist the detrimental effects of B. fabae on the plant growth and yield. In this concern, the efficiency of test biocontrol agents seemed to be in the order: T+S > Ex 1 +Ex 2 > T > S > Ex 2 > Ex.

Polymeric antimicrobial agents represent a new and important direction that is developing in the field of antimicrobial agents. Antimicrobial activity of two newly synthesized polymers: a modified poly (methylmethacrylate-co-vinylbenzoylchloride) and a modified linear poly (chloroethylvinylether-co-vinylbenzoylchloride) have been investigated and found to be active. Both polymers have showed a broad antimicrobial activity against C. albicans and C. tropicalis. Minimal inhibitory concentrations (MIC's) for poly (methylmethacrylate-co-vinylbenzoyl chloride) were 100, 75 and 100 microg/ml in case of C. albicans (ATCC 2091), C. albicans (SC5314) and C. tropicalis, respectively. However, polycholoroethylvinylether-covinylbenzoylchloride inhibited C. albicans (ATCC 2091), C. albicans (SC5314) and C. tropicalis with minimum inhibitory concentration values (MIC's) of 150 microg/ml against the three tested Candida strains. Mode of action studies of both polymers on the medically important yeasts, C. albicans and C. tropicalis revealed that poly (methylmethacrylate-co-vinylbenzoylchloride) induced cytotoxicity, DNA damage, and altered cell permeability and morphology, which was manifested as aggregated and swollen yeast cells (C. albicans ATCC 2091) by fluorescent microscopy examination. Poly (chloroethylvinylether-co-vinylbenzoylchloride) increased cell permeability, and respiration for C. albicans and C. tropicalis. The tested polymers at 50 microg/ml had pronounced effects on C. albicans and C. tropicalis cell wall phosphopeptidomannane, proteins, sugars and phosphorus. Generally, the two polymers proved effective against the tested microorganisms, but growth inhibitory effect varied according to the composition of the polymer active group. Many investigators consider polymeric antimicrobial agents as a potential new approach for enhancing the efficiency of some existing antimicrobial agents, including prolonged activity, reduce their toxicity, as well as reduce the environmental issues associated with product use.

Lake Bardawil represents a hyper-saline shallow (50-600 cm deep) water basin lying along the northern shore of Sinai. Surface water samples were collected monthly from this lake for physico-chemical and microbiological analysis. Seasonal variations in the averages of temperature, pH and transparency of the tested water samples were determined. Seasonal averages of the total bacterial counts at 22 and 37°C, biovolumes of cells and bacterial biomass of the lake's water at different regions were also determined. In addition to the gram-negative pathogen, Edwardsiella tarda, faecal contamination indicators, total coliforms, faecal coliforms and faecal streptococci were counted in the lake's water samples from various regions during different seasons. The number of actinomycetes per milliliter of the lake's water samples were determined. Fifteen actinomycetes were isolated and screened for their antibacterial activity against E. coli and pathogenic E. tarda isolated from the same water samples. Five isolates of these actinomycetes showed antibacterial activities and nine of them were identified as Streptomyces. The most antibacterially active isolate was subjected to morphological, physiological and biochemical studies and identified as Streptomyces viridiviolaceus. The identified organism exhibited antimicrobial activities against the main indicator of water pollution, E. coli, pathogenic E. tarda, Corynebacterium michiganese B-33, Pseudomonas solanacearum B-3212 and Staphylococcus. No antimicrobial activities were recorded against Bacillus cereus, Micrococcus, Mycobacterium, Aspergillus niger, Candida albicans, C. tropicalis or Rhizopus nigricans.

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Gram-negative bacilli (GNB) are commonly implicated in clinical diseases. However, with their increasing resistance to antimicrobial agents, treatment becomes a challenge. This study has been conducted at King Abdulaziz University Hospital in Jeddah, Saudi Arabia over a period of one month from July to August 2011. Identification and antibiotic sensitivity tests of GNB were performed using standard microbiological methods and Vitek2 system. Extended spectrum beta lactamase (ESBLs) strains were detected using double disc synergy test and Vitek 2 system. A total of 176 Gram-negative bacilli were studied. The most frequently isolated organism was E. coli (38.07%) followed by Klebsiella pneumoniae (15.91%), Pseudomonas aeruginosa (11.93%), Proteus mirabilis (9.66%) and Acinetobacter baumannii (6.82%). Other Gram-negative bacilli were less frequent. Isolates were detected most frequently from ICU patients (26.70%). Urinary tract, wound and respiratory tract infections were implicated most often. Extended spectrum beta lactamase strains accounted for 20% of all Enterobacteriacae. The vast majority of the GNB isolates were resistant to many antibiotics. Carbapenems, tigecycline and amikacin were effective against most multi-drug resistant Enterobacteriacae. Pseudomonas aeruginosa was resistant to several antibiotics; most effective agents were ceftazidime (80.95%), aztreonam (76.19%), carbapenem (90.48%), amikacin (90.48%), fluoroquinolones (80.95%) and piperacillin (61.90%). Isolates of Acinetobacter baumannii and Stenotrophomonas maltophilia were mainly multi-drug resistant to most tested antibiotics. In view of high levels of antibiotic resistance encountered, continuous surveillance of antimicrobial susceptibility patterns is warranted.

The biodegradation of morpholine has attracted much interest because morpholine causes environmental pollution. Ten species belonging to nine genera were tested for their abilities to degrade morpholine in mineral salts medium containing morpholine (1 g/l). Mycobacterium sp. isolated from polluted water sample collected from Abu Za"baal lakes, effectively utilized morpholine as carbon, nitrogen and energy source. The tested Mycobacterium was able to grow in high concentrations of morpholine but the rapidly increase in pH of the growth medium and accumulation of ammonia inhibited bacterial growth and complete mineralization of morpholine. The molar conversion ratio of morpholine to ammonia was 1:0.89. Growing of the selected bacterium in liquid medium with 1 g/l morpholine at 37°C and pH 6.5, enhanced morpholine degradation. Addition of metyrapone to the growth medium inhibited morpholine degradation. Immobilization of Mycobacterium cells in sodium alginate increased morpholine degradation compared with free cells. At high concentrations of morpholine (4 to 6 g/l), there was a decrease in both cell viability and respiration of Mycobacterium but no genotoxicity was found.

This study aimed to determine the emergence and spread of resistant bacteria in Jeddah Ministry of Health hospitals. Sixteen month follow-up (January 2010 to April 2011) study was carried out and clinical isolates of hospitalized patients were collected, identified and their antimicrobial resistance was determined using two automated systems, Phoenix and Vitek 2. Results revealed that 6195 isolates were identified of which 94% (5846/6195) were Gram negatives. In Escherichia coli, the resistance was 40% ( M. A. Halwani et al.781