The effect of levofloxacin (LEV) and vitamin-C (VIT-C) individually or in combinations on initial bacterial adherence and pre-formed (mature) biofilms on the surface of urethral catheters was studied. The isolated and studied uropathogens in the present study showed considerable diversity, where the major pathogens were identified as E.coli, Klebsiella sp., Citrobacter sp., Enterobacter sp., Proteus sp. and Pseudomonas sp. Using the static adherence assay, addition of LEV and VIT-C each alone at sub MIC concentrations (0.25 MIC and 0.5 MIC) and (80 and 100 mg ml-1) respectively, reduced the initial adherence ability of bacteria to the catheter by 35-94%. Besides, the inhibitory effect on the mature biofilm was estimated to be 40-90% in the presence of (MIC and 2MIC) LEV or (80 and 100 mg/ml) VIT-C. The highest inhibitory effects on both the initial adherence and mature biofilm were recorded when 0.5 MIC levofloxacin was added. Combination of LEV and VIT-C significantly increased the inhibitory effect of both initial biofilm formation and the mature biofilm to 80-100%. In addition, scanning electron microscope (SEM) was used to verify the effect of the tested drugs on biofilm production. The obtained results confirmed the significant role of this combination in inhibition of urethral catheter biofilm formation.

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To the best of our knowledge, this is the first time to identify bioactive antimicrobial metabolites from retrieved compost microorganisms in Egypt. So, compost could be a beneficial area for research as a reliable and continuous natural source for different uncountable communities of bacteria. This article is protected by copyright. All rights reserved.

Thevetia peruviana and Plumeria rubra (family Apocyanaceae) are shrubs cultivated in Egypt for ornamental purposes. This study was done to compare the volatile oils of T. peruviana and P. rubra which were prepared by using the hydrodistillation method from fresh flowers and leaves of each plant. Identification and quantification of the oil components were carried out by GC/MS analysis. The major components of T. peruviana flowers oil were Nonadecane (37.69 %), followed by 1-Nonylcycloheptane (18.39%), while Perilla alcohol (20.49%), β-ylangene(10.62%) and β-Elemene (7.19%) were predominant in the leaves oil. On the other hand, the major constituents of P. rubra flowers oil were Methyl dihydroepi-jasmonate (35.41%), Linalool (14.31%) and Methyl jasmonate (11.99%), while 1-Nonylcycloheptane (32.16%) and Menthol (17.89%) were of highest abundance in the leaves oil. Also, the antimicrobial activity was investigated against Staphylococcus aureus ATCC 4175, Escherichia coli ATCC 10536, Pseudomonas aeruginosa CNCM A21, and Candida albicans ATCC 60193. The minimum inhibitory concentrations (MIC) were determined and compared with those of standard antibiotics (Ofloxacin and Amphotericin B), the tested oils showed a good inhibitory effect against the investigated microbial strains with a minimum inhibitory concentration (MIC) range of 25 to 300 µg/mL except for the P. rubra leaves oil, which showed no activity against Pseudomonas aeruginosa.

Aims: Lower respiratory tract infections (LRTIs) have been identified by the World Health Organization as the most deadly infectious diseases and a pervasive public health problem, causing increased hospital admissions, mortality and antibiotic use.This study aims to determine the most common and resistant bacteria that cause LRTIs and prepare an appropriate vaccine to reduce and prevent potential future infections. Methods and Results:Our survey was conducted by collecting respiratory exudate specimens. The most predominant and resistant types were Klebsiella pneumonia and Pseudomonas aeruginosa. The lipopolysaccharides (LPS) were extracted using a modified hot phenol method to prepare the vaccine. The LPS were then activated and conjugated. The immunogenicity of the prepared singles and combined vaccines was determined through an in vivo assay using BALB/c mice. The prepared vaccine provided high protection against the lethal dose of both bacteria in mice. The combined vaccine shows a significant value in achieving high immunization. Conclusion:These findings demonstrate the potential of the bacterial LPS molecules to be used as effective vaccines.Significance and Impact of Study: Developing an effective single and combined vaccine against P. aeruginosa and K. pneumonia can protect and reduce LRTI incidence.

Background: Cellulose, the major component of the plant cell wall, is the most abundant and cheap polymer on earth. It can be used by varieties of cellulolytic enzymes. Cellulases can hydrolyze cellulose to its glucose monomers, which can be fermented to many biotechnological products, such as biochemicals, bioplastics, and biofuels. Actinomycetes are potential sources of cellulases. Objective: The current study sheds light on the cellulolytic activity of Thermobifida cellulosilytica, a previously isolated thermophilic actinomycete, and the analysis of the lignocellulases produced in the secretome as a result of induction by different carbon sources. Methods: The cellulolytic activity was qualitatively confirmed by Congo red method showing a large halo zone around the colonies. The activity was also assayed using the 3,5-dinitrosalicylic acid (DNS) method. The secretome analysis was conducted by liquid chromatography-tandem mass spectroscopy (LC-MS/MS) based proteomic approach. Results: The cellulolytic activity increased by two folds upon the growth of T. cellulosilytica on rice straw (RS) as a complex substrate comparatively to Carboxymethylcellulose (CMC) as a simple one. These results were highly assured by LC-MS/MS. Where more proteins (n=31) were produced in the RS secretome, CMC produced only six proteins, including only one cellulase. Different classes of proteins produced in the RS secretome were cellulases (26%), hemicellulases (16%), proteases (10%), and others (48%). Conclusion: Lignocellulases are inducible enzymes. RS as a complex substrate induced T. cellulosilytica for the expression of more lignocellulolytic enzymes than CMC.