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The activity concentrations of some radionuclides ( 238 U, 234 U, 230 Th, 226 Ra, 232 Th, 40 K and 235 U) were measured by γ-ray spectrometry in order to study their behavior and the relation between them in Carboniferous rock samples collected from Gabal (mountain) Um-Hamd, southwestern Sinai, Egypt. The whole samples are located in the two limbs and trough of a synclinal form structure to identify the radionuclides migration processes which have occurred in these rock samples. The average activity concentrations of 238 U

The search of novel strains continues to be of great importance in research around the world for pharmaceutical, industrial, agricultural and biomining applications. The present study aims to investigating the microbial diversity of rock samples collected from Um Bogma formation, southwestern Sinai, Egypt which was chosen for its unique location, geological and physicochemical properties. The studied samples showed small microbial diversity and low microbial count. A total of ten isolates of actinobacteria and ten isolates of fungi were isolated and characterized phenotypically. The results indicated that all the isolated actinobacteria belong to the genus Streptomyces. They were all halotolerant with some showing antimicrobial activities when tested against Bacillus subtilis, Pseudomonas aeruginosa ATCC 9027, Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 8739, Candida albicans and Aspergillus flavus. On the other hand, all the studied fungal isolates belong to the genus Aspergillus. They showed resistance to the antifungal nystatin when a concentration of 50 µg per ml was used. The studied locations is characterized by their harsh conditions which does not support the growth of most microorganisms which includes a temperature ranging from below 0°C at night to above 46°C throughout the day, low water content and organic matter hosting radioactive and heavy elements. Rock-dwelling microbial communities that survived such conditions open further

The capacity of the microorganisms in ore transformations makes bioleaching technique a very interesting alternative to conventional processes. Radiometric studies indicate high uranium contents in ore and waste samples. This paper describes the suitable fungus species for mobilization of U from low-grade U ores and their resulting wastes. The high bioleaching efficiency in waste samples is mainly attributed to the presence of high sulfate contents in these samples which converted by the aiding of microorganisms into sulphuric acids and hence, increase the bioleaching efficiency. Fungal leaching technique demonstrated an adequate recovery of uranium, with an efficient and cost-effective means from waste samples and respect to the reuse of waste for economic and environmental purposes

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