Biochemical constituents and master elements (Pb, Cr, Cd, Fe, Cu, Zn, Hg, B, Al, SO, Na, K, Li, Ca, Mg, and F) were investigated in six different seaweed species from Abu Qir Bay in the Egyptian Mediterranean Sea coast. The moisture level ranged from 30.26% in Corallina mediterranea to 77.57% in Padina boryana. On dry weight basis, the ash contents varied from 25.53% in Jania rubens to 88.84% in Sargassum wightii. The protein contents fluctuated from 8.26% in S. wightii to 28.01% in J. rubens. Enteromorpha linza showed the highest lipids (4.66%) and carbohydrate contents (78.95%), whereas C. mediterranea had the lowest lipid (0.5%), and carbohydrate contents (38.12%). Chlorophylls and carotenoid contents varied among the species. Total antioxidant capacity of the tested green seaweeds had the highest activities followed by brown and red seaweeds which had a similar trend of phenol and tannins contents. High reducing power was observed in all tested seaweeds extract except Ulva lactuca. Brown species had the highest amount of elements followed by red and green seaweeds. Notably, SO recorded the highest level in the tested green species (108.05 mg/g dry weight (DW)). The Ca/Mg and K/Na ratios reflected highly significant difference between seaweed species. This study keeps an eye on 29 parameters and by applying stepwise multiple regression analysis, prospective equations have been set to describe the interactions between these parameters inside seaweeds. Accordingly, the tested seaweeds can be recommended as a source of healthy food with suitable ion quotient and estimated daily intake values.

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Eutrophication of coastal waters is considered one of the major threats in marine ecosystems. Therefore, continuous monitoring is urgently needed to define potential risk zones. The present study is an attempt to test the applicability of the trophic state indices (TRIX) and Carlson's indice for scaling the eutrophication status of Lake Mariout in concert with a number of physicochemical descriptors aimed to select the most relevant of their ecological quality directed to increase fish production. Water samples were investigated seasonally during 2014. The range and annual average values of Physicochemical parameters were 18-27.5°C (23.20±0.52°C) for Temperature; 0.28-7.40‰ (3.70‰±1.69‰) for Salinity; 7.84-8.84 for pH; 0.60-5.24meq/l (1.97 ±0.43meq/l) for Total alkalinity; 0.14-10.71mg/l (4.91±2.98mg/l) for DO; 0.01-2.6mg/l (1.35±0.32mg/l) for BOD; 3.2-134.4mg/l (56.35±27.89 mg/l) for OOM; and 16.30-161.00 mg/l (63.80±24.70) for Total suspended solids;. The results of nutrient salts range and mean concentration (μM) were from 0.20 to 118.30 (15.61±15.46) for Ammonium; from 0.05 to 22.48 (3.43±3.38) for Nitrite; from 0.14 to 66.67 (13.50±7.78) for Nitrate; from 0.39 to 157.26 (39.28±43.79) for DIN; from 0.32 to 123.55 (33.64±18.77) for total nitrogen; from 0.10 to 45.30 (8.27±10.28) for reactive phosphate; from 0.04 to 49.60 (7.98±6.93) for total phosphorus; and from 2.14 to 226.16 (39.97±21.85) for silicate. Chlorophyll-a ranged from 3.95 to 130.3µg/l (28.51±21.99µg/l). According to seasonally calculated TRIX and Carlson's trophic state indices values, the sites are ranked in a descending order from very high to moderate eutrophic level for most stations, revealing the existence of anthropogenic stress. MATERIALS AND METHODS Area of study and sampling: Lake Mariout is one of the main fishing grounds of Alexandria located between longitude 29° 47.1′ to 29° 50.4′ E and latitude 31° 7.5′ to 31° 9′ N (Saad et al. 2017). The Lake is a shallow brackish water basin, its water depth ranges from 60 to 150 cm. It lies at the north of the Nile Delta, southeast of Alexandria; the lake is divided by artificial embankments into four basins (Fig. 1). In recent years, Lake Mariout was considered as an oxidation pond for Alexandrian waste water and agricultural wastes, discharged to it by the newly constructed plant stations. In order to evaluate the lake's water quality, 10 surface water samples from the Lake beside Qalaa, El-Umum drains, and Nubaria canal were collected seasonally in winter, spring, summer, and autumn 2014 (Fig. 1). Water samples were taken manually by attaching a cleaned 1Lpolyethylene bottle immersing to a depth 20-cm below the surface water. Methods of Analysis Water temperature was measured using a thermometer sensitive to 0.1°C; water pH and salinity were measured using a pocket pH meter (model 201/digital pH meter) and a Beckman salinometer (Model NO.R.S.10), respectively. Total alkalinity was determined according to standard Methods (APHA 1995).

A novel marine fungus was isolated and classified as Aspergillus flavus strain EGY11. The heat-inactivated form of isolated Aspergillus flavus was investigated and evaluated as a new eco-friendly and highly efficient biosorbent for removal of toxic heavy metals such as Cd(II), Hg(II), and Pb(II) from aqueous solutions. The SEM morphological studies of biosorbent-loaded metal ions confirmed their direct binding on the surface of heat-inactivated Aspergillus flavus. The metal biosorption capacity values were determined and optimized by the batch technique in the presence of various experimental controlling factors such as pH, contact time, biosorbent dosage, initial metal ion concentration, and coexisting species. The maximum metal capacity values of Cd(II), Hg(II), and Pb(II) were cauterized as 1550 (pH 7.0), 950 (pH 7.0), and 1000 μmol g (pH 6.0), respectively. The equilibrium time for removal of metal ions was identified as 40 min. The maximum sorption capacity values (1200.0-4000.0 μmol g) were established by 5.0 mg as the optimum mass of biosorbent. The collected biosorption data obtained from the equilibrium studies using the initial metal ion concentration were described by the Langmuir, Freundlich, Brunauer-Emmett-Teller (BET), and Dubinin-Radushkevich isotherm (D-R) isotherm models. The potential implementation of heat-inactivated Aspergillus flavus biosorbent for heavy metal removal from different water samples was successfully accomplished using multistage microcolumn technique. The results refer to excellent percentage recovery values in the ranges 92.7-99.0, 91.3-95.6, and 95.3-98.2% for the biosorptive removal of Cd(II), Hg(II), and Pb(II), respectively, from the examined environmental samples.