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thus allowing the re-use of wastewater for the irrigation of plants that produce abundant bio-oils and for the irrigation of low-quality soils. Chlorella vulgaris was grown in Om El-Resh drain water as growth medium, after enrichment with nitrogen and phosphorous. Castor seeds were cultivated in a greenhouse at the Algal Biotechnology Unit, National Research Centre, Egypt. Fifteen days later, transplants were irrigated by untreated wastewater (WW); wastewater treated with microalgae (WW+A); or wastewater treated with microalgae followed by removal of microalgae (WW-A). Oil extraction was performed by seed warming and grinding with n-hexane, followed by soaking, filtration, and passage through Silica gel 60. Esterification was performed, and then fatty acid methyl esters (FAMEs) were determined. The results indicated that the wastewater treatment markedly affected seed oil content. The WW+A treatment led to the highest seed oil yield (41.8%), followed WW-A treatment (28.14%), and the WW treatment (25.12%). FAME analysis indicated that the presented fatty acids of castor oil were C16 and C18 and ricinoleic acid (C18:1) was the most abundant (83.1 to 84.63%). In spite of the higher seed oil content when plants were grown in WW+A, there were differences in the fuel proprieties of seed oils in the different groups, based on American Society for Testing and Materials criteria. Our results suggest that wastewater can be successfully used for irrigation of soils that have poor fertility to produce bio-oils during land reclamation.

Spirulina platensis, a blue-green alga of Cyanophyta family, was isolated from Wady El-Natron district, El-Behara Governorate, 30.58333°N 30.33333°E. The dried biomass was determined to have a nutritional value of 61.0% protein, 23.5% carbohydrates, and 6.21% lipids. HPLC analysis revealed presence of eight essential amino acids (23.7 g•100 g −1 ) and nine non-essential amino acids (28.7 g•100 g −1 ). The major essential amino acid is methionine (4.8 g•100 g −1 ). However, glutamic acid is a significant non-essential amino acid in dried powder (7.8 g/100 g). Additionally, three major sugars totaling 3.108 g•100 g −1 of dried S. platensis are identified. Along with minerals and a few polyphenolic compounds, various forms of vitamin B (B-1, 2,3,6,9, and 12) were detected. C-phycocyanin was extracted from wet biomass using organic acid extraction and cold maceration methods, followed by purification with various concentrations of ammonium sulfate. The two procedures were compared to determine the most efficient one for maximum C-PC recovery, and then the extract was screened an antioxidant using DPPH & ABTS beside to anticancer agents against the human breast (MCF-7), human colon (HCT-116), and human liver (HepG 2) carcinoma cell lines by 5.1%, 14.3%, and 31.2% inhibition, respectively, with cold maceration being the most efficient and effective process.