Mitigation of CaCO3 Influences on Ipomoea batatas Plants Using Bacillus megaterium BSM 2894 var.

Under Egyptian soil conditions, when phosphorus fertilizers were applied to the soil, it gets fixed and converts to unavailable form, leading to low solubility for the plant. This study were fulfilled on sweet potato (cv. Beauregard) under undesirable soil properties (CaCO3 10.8 vs 11.3%) using Bacillus megaterium DSM 2894 strain under different five mono calcium phosphate (CSP) levels [(69(CSP20); 138(CSP40); 207 (CSP60); 276 (CSP80) and 345 ((CSP100) kg ha-1 of calcium superphosphate (CSP)] to arise the potential efficiency of some nutrients uptake and decease the applied total amount of CSP in 2019 and 2020 seasons. The results mentioned that highest values were obtained by inoculated plants with DSM2894 strain under 20, 60 and 100% of CSP for all studied nutrients content in both seasons, except Mn content in the 2019. Also, inoculated plants with DSM2894 under previous treatments for all tuberous root nutrients content, except Fe and Zn contents in both seasons, in addition protein and anti-radical power and total yield. Statistically, leaf nutrients uptake and tuberous root content were highly significant affected by DSM and CSP combination. Appling of phosphorus fertilizer with DSM2894 mixture was gave the best values as compared with phosphorus fertilizer or DSM2894, individually.

Diverse thermophilic Bacillus species with multiple biotechnological activities are associated within the Egyptian soil and compost samples

Thermophilic strains of Bacillus can express enzymes of higher thermal stability, which allows carrying out industrial fermentations under higher temperatures. This lowers the contamination potential, accelerates mixing rates and facilitates the recovery of fermentation end products. The present study was thus designed to isolate and characterize thermophilic Bacillus cultures from soil and compost samples. Forty-two thermophilic Bacillus isolates could be identified employing morphological, physiological and the 16S rRNA gene sequencing analyses. The isolates showed a high degree of biological diversity involving 13 Bacillus species and 1 subspecies but were dominated by Bacillus licheniformis. Phylogenetic analysis of B. licheniformis isolates based on the DNA sequencing of gyrA and rpoB genes presented them in two main genetic groups. Isolates of five thermophilic species including B. licheniformis, Bacillus altitudinis, Bacillus paralicheniformis, Bacillus subtilis and Bacillus thermoamylovorans showed multiple activities to degrade all of cellulose, hemicellulose and lignin. Those multifunctional thermophilic Bacillus isolates can be harnessed in the degradation of plant wastes for the production of biofuels and compost.

Inoculation and colonization of isolated entomopathogenic fungi Beauveria bassiana in rice plants, Oryza sativa L. through seed immersion method

Background The aims of the present study were to isolate and identify native entomopathogenic fungi, Beauveria bassiana from the Egyptian soil and to evaluate the artificial establishment of B. bassiana as endophytes in rice plants through seeds immersion. Results Ten soil samples were collected from different cultivated fields at the Ismailia Governorate. Only one sample was positive with a ratio of 10%. Sequencing of the internal transcribed spacer (ITS) region indicated that the isolate obtained from the soil sample belongs to B. bassiana and was registered under the accession no. MN337282. To test the endophytic colonization of B. bassiana, rice seeds were soaked by B. bassiana with a concentration of 5 × 107 spores/ml, to test when B. bassiana become an endophyte in rice plants. The plants were examined for endophytic presence of B. bassiana, 30 days post treatment. PCR amplification using fungal specific primers for a conserved region of β-tubulin gene yielded identical 360 bp products from both B. bassiana and rice treated plants. Conclusion The results showed that seeds immersion with a conidial suspension proved to be a good method to introduce B. bassiana into rice leaves to protect the rice plants against stem borers.

Isolation and optimized production of putative antimicrobial compounds from Egyptian soil isolate Streptomyces sp. MS. 10

Background The rapid spread of antibiotic resistance has increased research interest in the discovery of natural products, mainly from actinomycetes, which have been the primary source of antimicrobial compounds. This study aimed to isolate, characterize, and optimize the production of some of the bioactive compounds from bioactive soil actinomycetes. Results One promising soil actinomycete, which was molecularly identified as Streptomyces sp. and designated as Streptomyces sp. MS. 10, showed broad-spectrum antimicrobial activity, including activity against methicillin-resistant Staphylococcus aureus. Thus, it was selected for isolation of its major bioactive compounds. Polymerase chain reaction amplification of the genes responsible for antibiotic biosynthesis showed the presence of genes encoding type I and type II polyketide synthase. Liquid chromatography-mass spectrometry analysis found that the major antimicrobial compounds produced by Streptomyces sp. MS. 10 were weakly ionized bioactive secondary metabolites. A large-scale fermentation experiment of Streptomyces sp. MS. 10 using pre-optimized culture conditions followed by bioassay-guided chromatographic separation of its secondary metabolites resulted in the isolation of putative bioactive compounds that were identified as fatty acids using proton nuclear magnetic resonance spectroscopy. Conclusions Egyptian soil is still a good source for exploring bioactive actinomycetes. Additionally, this study highlighted the importance of combining both physicochemical and genotypic characterization with spectroscopic analysis of the major natural products when isolating bioactive metabolites.

The Libyans

Our picture of the Libyans in the New Kingdom and Third Intermediate Periods is heavily dependent upon Egyptian textual and visual evidence. This chapter reviews the much sparser archaeological evidence for Libyan culture, combining material from the fringes of Egypt with data from information from Libya proper. The models that scholars have used to assess this material are discussed particularly in the light of the sparse material evidence on Egyptian soil during the times of Libyan rule. Recent work on the archaeology of nomads is also refining these models and shining light upon their social complexity and adaptability across the nomadic-settled continuum.