A field experiment was conducted, June 2009 to study the effects of foliar applications of different concentrations of seaweed extract of Ulva lactuca (Ulvaceae) and Gracilaria dendroides (Gracilariaceae) on nutrient uptake, growth and yield of sunflower plant. There were five treatment control and two concentration 0.4 and 0.6 % w/v from each algal extract, this treatment applied at 3 times; first one at the seedling stage (20 days after sowing), the second at the flowering stage (40 days after sowing), while the third one before yield stage (70 days after sowing). Application of algal extract significantly increase fresh and dry weight of root and shoot, chlorophyll a, chlorophyll b and carotenoids rather than the control, especially with 0.6% extract of G. dendroides. At harvest stage, application of seaweed significantly increase both root and shoot fresh and dry weight, plant height, head diameter, seed index (weight of 1000 seed), seed yield as compared to control. Also, the highest growth parameters were observed in plant treated by 0.6% extract of G. dendroides, except plant height. Highest oil content was observed at 0.6 % G. dendroides extract, followed with 0.6% U. lactuca extract application (34.05 and 30.55%, respectively). The application of extract of 0.4 % and 0.6 % for both studied algae significantly increased seed yield of sunflower by 20.94, 40.31, 30.29 and 28.73%, respectively, compared to control. Improved nutrient uptake (Na and K) was also observed with seaweed extract applications. Thus, foliar applications of seaweed extracts could be a promising option for yield enhancement and high oil yield production of sunflower plant.

Chitinolytic activity and antibiosis are gaining prominence in various biotechnological fields. Dead fungal biomass (DFB) was used as a mycostimulator of chitinase production and antibiosis by Aspergillus fumigatus. The presence of DFB stimulated the synthesis of various secondary metabolites by A. fumigatus that were detected by gas chromatography-mass spectrometry analysis such as 6,8-Di-C-á-glucosylluteolin; bistrimethylsilyl N-acetyl eicosasphinga-4,11-dienine; curan-17-oic acid, 19,20-dihydroxy-, methyl ester, (19S)-; spiro[5à-androstane-3,2′-thiazolidine; retinal; Androsta-1,4-dien-3-one; Panaxydol; Costunolide; Cyclo-(glycyl-L-tyrosyl); and 2-amino ethane thiolsulfuric acid. Chitinase activity was 42.9 Units/mL with the presence DFB, where it was 10.3 Units/mL without DFB. The maximum activity of chitinase was observed at 1.5 g of dead fungal biomass, at 4 h, 50 °C and pH 6. Thermodynamic properties showed ∆H° and ∆S° values of 126 KJ mol-1 and 432 J mol-1 K-1, respectively, indicating an endothermic reaction up to 60 °C. Deviation in ∆G° values confirmed that the reaction at 10 to 20 °C is a nonspontaneous reaction, and at 30 to 60 °C the reaction has a spontaneous nature. DFB encouraged the antimicrobial activity against Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, Aspergillus fumigatus, Mucor circinelloides, and Candida albicans with 2.3, 2.2, 2.8, 0.8, 0.7, and 2.2 mm inhibition zones, respectively.

Microalgae have been used widely in bioremediation processes to degrade or adsorb toxic dyes. Here, we evaluated the decolorization efficiency of Chlorella vulgaris and Nostoc paludosum against two toxic dyes, crystal violet (CV) and malachite green (MG). Furthermore, the effect of CV and MG dyes on the metabolic profiling of the studied algae has been investigated. The data showed that C. vulgaris was most efficient in decolorization of CV and MG: the highest percentage of decolorization was 93.55% in case of MG, while CV decolorization percentage was 62.98%. N. paludosum decolorized MG dye by 77.6%, and the decolorization percentage of CV was 35.1%. Metabolic profiling of C. vulgaris and N. paludosum were performed using NMR spectroscopy. Based on 1D and 2D NMR data, 43 compounds were identified in the polar extract of C. vulgaris, while 34 polar metabolites were successfully determined in N. paludosum. The identified compounds included carbohydrates, amino acids, organic acids, dipeptides, steroids and phenols. Statistical analysis was carried out to recognize the pattern of metabolite variation between control and dye treated samples. Principal component analysis (PCA) and hierarchical cluster analysis showed that samples treated with MG are clearly separated from the control in both types of algae. Based on heat map data, the level of carbohydrates and amino acids concentrations are strongly affected by bioremediation of MG dye compared with CV dye. In conclusion, the present study proved that CV and MG dyes are considered as stress factors and the studied algae species exert their bioremediation activity without the dyes being absorbed into the cells.

This study was designed to identify the bioactive constituents of the red alga Gracilaria dendroides and one green alga Chlorella vulgaris and Microcystis sp. (cyanobacteria) by GC /Mass and HPLC analysis and assay the cytotoxic activity of the methanolic extract from the three species against three types of human cancer cell lines (liver HEPG-2, colon and breast MCV-7). The research was performed as an in vitro study. The effect of extract on proliferation of cell lines was measured by Methyl thiazolyl tetra zolium (MTT) colorimetric method. The results showed that the compounds identified by GC-MS were 19 compounds in G. dendroides, 11 compounds in Chlorella and 12 compounds in Microcystis,. The most abundant compounds were fatty acids, methyl esters and terpenoids. HPLC analysis identified 4 compounds in Gracilaria and 6 compounds in Chlorella and Microcystis. Crude extract of Gracilaria had the strongest activity on HepG-2 cell lines with IC 50 value 15.46 μg/ml. Concerning MCF-7 cell lines, the most potent crude extract was the Chlorella vulgaris (IC 50 value of 15.53 μg/ml). On the other hand, evaluation the cytotoxic activity for the three algae species extracts against epithelial colorectal adenocarcinoma cells (CaCO-2) showed higher activity for Chlorella vulgaris with IC 50 = 14.63 μg/ml. Accordingly, we can say that Chlorella had the strongest activity on MCF-7 and (CaCO-2) cell lines while HepG-2 cell lines most affected by Gracilaria extract.

Algal blooms at the major water treatment plants in Egypt have been reported since 2006. While previous studies focused on algal types and their correlation with disinfection by-products, correlation between raw water quality and algal blooms were not explored. Therefore, a survey of Nile water quality parameters at a major water intake in the Greater Cairo Urban Region was conducted from December 2011 to November 2012. Bench-scale experiments were conducted to evaluate the effectiveness of the conventional chloride/alum treatment compared with combined Cl/permanganate pre-oxidation with Al and Fe coagulants during the outbreak period. Addition of permanganate (0.5 mg/L) significantly reduced the chlorine demand from 5.5 to 2.7 mg/L. The applied alum coagulant dose was slightly reduced while residual Al was reduced by 27% and the algal count by 50% in the final treated waters. Applying ferric chloride and ferric sulfate as coagulants to waters treated with the combined pre-oxidation procedure effectively reduced algal count by 60% and better the total organic carbon reduction and residual aluminum in the treated water. Multivariate statistical analysis was used to identify the relationship between water quality parameters and occurrence of algae and to explain the impact of coagulants on the final water quality.