National Institute of Oceanography and Fisheries, Egypt

About: National Institute of Oceanography and Fisheries, Egypt is a facility organization based out in Alexandria, Egypt. It is known for research contribution in the topics: Chemistry & Biology. The organization has 183 authors who have published 139 publications receiving 1665 citations. The organization is also known as: Alexandria Institute of Hydrobiology.

Green synthesis of iron oxide (Fe 3 O 4 ) nanoparticles using two selected brown seaweeds: Characterization and application for lead bioremediation

Abstract: The exploitation of different plant materials for the biosynthesis of nanoparticles is considered a green technology because it does not involve any harmful chemicals. In this study, iron oxide nanoparticles (Fe3O4-NPs) were synthesized using a completely green biosynthetic method by reduction of ferric chloride solution using brown seaweed water extracts. The two seaweeds Padina pavonica (Linnaeus) Thivy and Sargassum acinarium (Linnaeus) Setchell 1933 were used in this study. The algae extract was used as a reductant of FeCl3 resulting in the phytosynthesis of Fe3O4-NPs. The phytogenic Fe3O4-NPs were characterized by surface plasmon band observed close to 402 nm and 415 nm; the obtained Fe3O4-NPs are in the particle sizes ranged from 10 to 19.5 nm and 21.6 to 27.4 nm for P. pavonica and S. acinarium, respectively. The strong signals of iron were reported in their corresponding EDX spectra. FTIR analyses revealed that sulphated polysaccharides are the main biomolecules in the algae extracts that do dual function of reducing the FeCl3 and stabilizing the phytogenic Fe3O4-NPs. The biosynthesized Fe3O4-NPs were entrapped in calcium alginates beads and used in Pb adsorption experiments. The biosynthesized Fe3O4-NPs alginate beads via P. pavonica (Linnaeus) Thivy had high capacity for bioremoval of Pb (91%) while that of S. acinarium (Linnaeus) Setchell 1933 had a capacity of (78%) after 75 min. The values of the process parameters for the maximum Pb removal efficiency by Fe3O4-NPs alginate beads synthesized via P. pavonica (Linnaeus) Thivy were also estimated.

Total and leachable heavy metals in muddy and sandy sediments of Egyptian coast along Mediterranean Sea.

Abstract: The assessment of marine pollution due to metals was made for surficial sediments sampled from 20 sites along Mediterranean coast of Egypt. The samples were dried, acid digested and analyzed for leachable and total heavy metal contents (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) by flame atomic absorption spectrophotometer (air-acetylene) with deuterium background correction. Evaluation of the heavy metals pollution status was carried out using enrichment factors (EFs), the effect range-low (ERL) and the effect range-median (ERM). The study showed high concentrations of Cd, Co, Pb, Ni and moderate concentrations of Cr, Cu and Mn were contaminated in the sediments of studied sites. The results of Spearman correlation, factor and cluster analysis of the heavy metals analyzed in the collected sediment were discussed. The main source of contamination is the offshore oil field and industrial wastes, which arise due to the ineffective and inefficient operation equipments, illegal discharge and lack of supervision and prosecution of offenders.

The Fayum Depression and Its Lakes

Abstract: The Fayum is a depression below sea level, formed by wind erosion 1.8 million years age, covering ca 12,000 km 2 . It consists of two lacustrine complexes, Birket Qarun and the two artificial Wadi el-Rayan lakes. Lake Qarun is a saline rem- nant of the historical freshwater Lake Moeris. It used to be supplied by Nile water between its formation (about 1980 bc) and the Ptolemaic period (323-246 bc). The lake is no longer connected to the Nile and needs to be supplied with pumped water that evaporates in its basin. Consequently, the lake showed a strong increase in salinity, especially during the twentieth century. It evolved from a brackish to a hypersaline state, with incisive repercussions on all biota. In Wadi el-Rayan area, two successive lakes, separated by a waterfall, were created as a reservoir for drainage wastewater. These lakes currently exceed the capacity of Lake Qarun. The physical and chemical variables, phytoplankton, zooplankton, macrobenthos and fish of the two lake com- plexes are discussed. Among other things, it is argued that the rapid change in salinity of Lake Qarun excludes the presence of endemic species in its fauna.

Artificial intelligence modeling of cadmium(II) biosorption using rice straw

Abstract: The biosorption efficiency of Cd2+ using rice straw was investigated at room temperature (25 ± 4 °C), contact time (2 h) and agitation rate (5 Hz). Experiments studied the effect of three factors, biosorbent dose BD (0.1 and 0.5 g/L), pH (2 and 7) and initial Cd2+ concentration X (10 and 100 mg/L) at two levels “low” and “high”. Results showed that, a variation in X from high to low revealed 31 % increase in the Cd2+ biosorption. However, a discrepancy in pH and BD from low to high achieved 28.60 and 23.61 % increase in the removal of Cd2+, respectively. From 23 factorial design, the effects of BD, pH and X achieved p value equals to 0.2248, 0.1881 and 0.1742, respectively, indicating that the influences are in the order X > pH > BD. Similarly, an adaptive neuro-fuzzy inference system indicated that X is the most influential with training and checking errors of 10.87 and 17.94, respectively. This trend was followed by “pH” with training error (15.80) and checking error (17.39), after that BD with training error (16.09) and checking error (16.29). A feed-forward back-propagation neural network with a configuration 3-6-1 achieved correlation (R) of 0.99 (training), 0.82 (validation) and 0.97 (testing). Thus, the proposed network is capable of predicting Cd2+ biosorption with high accuracy, while the most significant variable was X.

Isolation and enumeration of marine actinomycetes from seawater and sediments in Alexandria.

Abstract: Actinomycetes were isolated from near-shore marine sediments and water at four different sites in Alexandria. Statistical analysis revealed that variation in temperature, pH, and dissolved phosphate were of insignificant values, but that variation in total nitrogen and organic matter were significant. The treatment of sediments and water samples by heat resulted in a selective reduction of the nonactinomycetal heterotrophic microflora. Four selective culture media were used for counting actinomycetes in marine water and sediments. The starch nitrate medium favored the growth of these microorganisms. The diversity and counts of actinomycetes varied with the seasonal variation, and the highest counts were detected in dry warm seasons. The numbers of this bacterial group in sediments exceeded by far their numbers in seawater. A positive correlation was found between population size and location. Actinomycetes were found in the highest numbers in the upper layers (0-20 cm depth). In a few cases, the counts of actinomycetes showed bimodal maxima 0-20 and 60-100 cm deep. Sediments were the best source of marine actinomycetes, and their distribution varied depending on the depth from which samples were collected. The ratio of actinomycetes to the total microflora ranged from 0.48 to 2.29, depending on location.