Physiological factors affecting the production of an antimicrobial substance by Streptomyces violatus in batch cultures

Egyptian Journal of Biology Vol.3 2001: 1-1

STR-990: SUSTAINABLE GROUTED HELICAL PILES: MATERIALS AND PERFORMANCE

Cementitious materials are widely used as a construction material all over the world. However, cement industry has high environmental impact such as the release of CO2 and the consumption of natural resources for its manufacturing energy. Therefore, reducing cement consumption is vital to achieve sustainable green construction practices. In this study, the effects of using treated oil sand waste (TOSW) as a partial replacement of cement in grouted helical pile applications were investigated. Fresh and hardened properties of the green grout incorporating different percentages of TOSW were evaluated. In addition, a model scale grouted helical pile with the green grout was tested to characterize its performance. The experimental results show that the properties of TOSW grout mixes were comparable to conventional grout and satisfy the strength and construction requirements of grouted piles. Moreover, tested grouted helical pile using the developed mixture exhibited similar geotechnical performance as those installed using conventional grout mix. Hence, TOSW can be implemented in grouted helical pile applications, which would assist in achieving sustainable construction

Evaluation of Feeding Stimulant Mixed with Chemical and Bio Insecticides on Certain Lepidopterous Pests and their Natural Enemies in Cotton and Soybean Fields

The Efficiency of feeding stimulants (Bioenhencer) was studied alone and in combinations with chemical insecticides or entomopathogens against the defoliating pests, Spodoptera littoralis (Boisd.) and Spodoptera exigua Hbn. (in fields of cotton and soybean) and the bollworms Pectinophora gossypiella Saunders and Earias insulana Boisd. (in cotton field), at Kafr El-Sheikh governorate during the season 2003. Its adversely influence on the natural enemies associated these pests in the two fields, were also undertaken. Laboratory results indicated that the feed stimulant was exhibited at a high degree of efficiency against the target lepidopterous larvae when combined with the chemical insecticide and the bioinsecticides. But no obvious effect was found when it was used alone. Field results indicated that, the addition of Bioenhencer (5%) to the chemical and bio insecticides enhanced their activity, where the damaged rate significantly affected in these treated plots as compared to the untreated ones, on both cotton and soybean fields. Moreover, bioenhancer and the bioinsecticide had the least harmful effect on the entomophagous insect populations. @JASE

Searching for molecular markers in head and neck squamous cell carcinomas (HNSCC) by statistical and bioinformatic analysis of larynx-derived SAGE libraries

Background: Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies in humans. The average 5-year survival rate is one of the lowest among aggressive cancers, showing no significant improvement in recent years. When detected early, HNSCC has a good prognosis, but most patients present metastatic disease at the time of diagnosis, which significantly reduces survival rate. Despite extensive research, no molecular markers are currently available for diagnostic or prognostic purposes. Methods: Aiming to identify differentially-expressed genes involved in laryngeal squamous cell carcinoma (LSCC) development and progression, we generated individual Serial Analysis of Gene Expression (SAGE) libraries from a metastatic and non-metastatic larynx carcinoma, as well as from a normal larynx mucosa sample. Approximately 54,000 unique tags were sequenced in three libraries. Results: Statistical data analysis identified a subset of 1,216 differentially expressed tags between tumor and normal libraries, and 894 differentially expressed tags between metastatic and non-metastatic carcinomas. Three genes displaying differential regulation, one down-regulated (KRT31) and two up-regulated (BST2, MFAP2), as well as one with a non-significant differential expression pattern (GNA15) in our SAGE data were selected for real-time polymerase chain reaction (PCR) in a set of HNSCC samples. Consistent with our statistical analysis, quantitative PCR confirmed the upregulation of BST2 and MFAP2 and the downregulation of KRT31 when samples of HNSCC were compared to tumor-free surgical margins. As expected, GNA15 presented a non-significant differential expression pattern when tumor samples were compared to normal tissues. Conclusion: To the best of our knowledge, this is the first study reporting SAGE data in head and neck squamous cell tumors. Statistical analysis was effective in identifying differentially expressed genes reportedly involved in cancer development. The differential expression of a subset of genes was confirmed in additional larynx carcinoma samples and in carcinomas from a distinct head and neck subsite. This result suggests the existence of potential common biomarkers for prognosis and targeted-therapy development in this heterogeneous type of tumor.Fundação de Amparo a Pesquisa do Estado de São Paulo/FAPESP [05/51467-0]; [04/12054-9]; [07/50894-7]Ludwig Institute for Cancer ResearchConselho Nacional de Pesquisas/CNPqCoordenacao de Aperfeicoamento do Pessoal do Ensino Superior/CAPE

The Application of Mediated Biosynthesized Green Silver Nanoparticles by Streptomyces griseorubens in Water Treatment

In the present study, a soil actinomycete was isolated from near the river Nile shoreline, Egypt. The identification of this isolate as Streptomyces griseorubens was performed using 16s rDNA. The sequence has been deposited in the Gene Bank with the accession number LC066679. Factors affecting the biogenesis of AgNPs were optimized by applying the Plackett-Burman factorial design. The maximum silver nanoparticles (AgNPs) biosynthesis (2.76 OD at 400 nm) was achieved in the trial No.9 that contained the following ingredients (g/L): Starch (20); MgSO4 (0.05); K‚ HPO4 (1.0); NaNO3 (2.0); AgNO3 (1.0) mmol/l; PH (7); incubated at temperature 30°C for 72 hr. The biosynthesized nanoparticles were characterized using spectroscopic techniques. AgNPs showed the characteristic UV spectra at a wavelength range 300 - 600 nm and a characteristic absorption peak was recorded at the wavelength of 400 nm. For AgNPs with absorbance height ofH≈2.56 a.u. and peak width at half maximum absorbance (PWHM) H≈120 nm which remained constant over a long period of time indicating its stability. FTIR spectra showed the functional group of the biomaterials capping the AgNPs. EDX confirmed the formation of the metallic silver nanoparticles, indicating the presence of proteinaceous cabbing. TEM micrograph showed spherical AgNPs in shape with an average diameter of 22 nm. The biosynthesized AgNPs showed high stability up-to two weeks. The conjugate (AgNPs/cellulosic fiber (C)) of Luffa aeygptiaca and (AgNPs/activated carbon (AC)) was applied for drinking water treatment, which resulted in fecal Coliform bacteria removal with a success of 99.9% as a water treatment application

Isolation and characterisation of an antimicrobial substance produced by Streptomyces violatus

Egyptian Journal of Biology Vol.3 2001: 11-2

Characterization of Carotenogenic Rhodotorula Strains Isolated from Delta Region, Egypt and their Potential for Carotenoids Production

Initial visual screening for most applicable strains visually based on cell-bound pigmented colonies from different sources in the Egyptian environment. Samples (n=25) of soil, milk, laban rayeb, and kareesh and Ras cheeses were screened for strains capable of producing carotenoids. Seven isolates showed fast growth rates and high content of carotenoids were further characterized. Physiological and molecular identification of the isolated yeast was done using API 32C and sequencing of 18S rRNA gene. The produced sequences were compared with reference 18S rRNA gene sequences available in NCBI GenBank database. Five yeasts strains (S-361, S-37, S-33, S-11 and S-10) out of seven were identified as R. diobovata [with accession no. KX866280, KX866279, KX866278, KX866276 and KX866275 respectively] and the rest were classified as R. mucilaginosa (S-5 and M-30) with accession no: KX866274 and KX866277. The carotenoid derivatives produced by R. diobovata S-361 and R. mucilaginosa S-5 strains were identified by chromatographic analysis (TLC and HPLC) to be b-carotene as a major fraction, torulene, torulene-like and torulahodine. The ability of R. diobovata S-361 strain to produce carotenoids from lactose hydrolyzed salt whey in bioreactor and high aeration led to promote growth resulted in high biomass production (22.7 g/l at day five). Also the production of yeast biomass was about 3.5 times higher yield than in Erlenmeyer flasks while high cellular carotenoids production obtained at day four (147 µg/g) and torulene was the most dominant carotenoids fraction, Cellular and volumetric carotenoids production in batch fermentation during 5 days was investigated. The highest cellular carotenoids were recorded in pellets of the culture of R. diobovata S-361

Evaluation of Feeding Stimulant Mixed with Chemical and Bio Insecticides on Certain Lepidopterous Pests and their Natural Enemies in Cotton and Soybean Fields

The Efficiency of feeding stimulants (Bioenhencer) was studied alone and in combinations with chemical insecticides or entomopathogens against the defoliating pests, Spodoptera littoralis (Boisd.) and Spodoptera exigua Hbn. (in fields of cotton and soybean) and the bollworms Pectinophora gossypiella Saunders and Earias insulana Boisd. (in cotton field), at Kafr El-Sheikh governorate during the season 2003. Its adversely influence on the natural enemies associated these pests in the two fields, were also undertaken. Laboratory results indicated that the feed stimulant was exhibited at a high degree of efficiency against the target lepidopterous larvae when combined with the chemical insecticide and the bioinsecticides. But no obvious effect was found when it was used alone. Field results indicated that, the addition of Bioenhencer (5%) to the chemical and bio insecticides enhanced their activity, where the damaged rate significantly affected in these treated plots as compared to the untreated ones, on both cotton and soybean fields. Moreover, bioenhancer and the bioinsecticide had the least harmful effect on the entomophagous insect populations. @JASE