الفهرس 
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Abstract
SUMMARY
Ten microalgae strains, i.e., five cyanobacteria strains viz. Anabaena fertilissima, Nostoc sp. B, Nostoc humifusum and Phormidium fragile strains and Wollea sp. were obtained from the cyanobacteria stock culture of Agric. Res. Microbiol. Dept., Soils, Water & Environ. Res. Inst. (SWERI), Agric. Res. Center, Giza (ARC), Egypt., other three cyanobacteria strains isolated from textile wastewater effluent (TWE) viz. Anabaena circinalis, Nostoc sp. A and Nostoc entophytum. As well as, two green algae viz. Chlorella vulgaris and Scenedesmus abundance, the first one was also obtained from the stock culture of Agric. Res. Microbiol. Dept., (SWERI) (ARC) Giza, Egypt, while the other one was obtained from Botany Department, Fac. Sci., Benha University, Kalubia, Egypt. The screened cyanobacterial strains are morphologically belonging to genus Nostoc. Phylogenetic analysis of the 16S rRNA gene sequences affiliated the isolates strains clearly to genus Nostoc with the closest similarity to KT763391.1 Nostoc sp. Bahar_E and KT763390.1 Nostoc sp. Bahar_M. Previously strain Nostoc sp A was identified as Anabaena orientalies, while strain Nostoc sp. B was identified as Nostoc muscorum. They were tested for their efficiency of removing color and heavy metals contaminants of the textile wastewater effluent (TWE) with red color collected from El-Shafie Factory for Garments located in EL-Mahalla EL-Kobra, East Delta, Gharbia Governorate, Egypt. It was stored in a holding tank before discharge into the river, which is solely generated by the dye house. The crude textile wastewater effluent was exposed to Lab work and greenhouse work in which the treated TWE with the most active microalgae strains in bioremediation process, i.e., (Nostoc sp. B and Nostoc sp. A) was applied for the irrigation of Vicia faba plants.
Results can be summarized:
Laboratory Work
General characters of TWE water was with dark red color a slight alkaline pH (7.50), Electric Conductivity (1.09 dSm-1), COD (20.19 ppm), total soluble salts (TS) (1.85 g/L), total dissolved solids (TDS) (1.67 g/L) and total suspended solids (TSS) (0.18 g/L). and the TWE water was dominated with the heavy metals of iron (Fe), manganese (Mn), boron (B), lead (Pb), arsenic (As), aluminum (Al), molybdenum (MO) and copper (Cu).
● All tested microalgae can successfully remove the heavy metals from TWE with different percentages ratio ranged from 3.73 to 97.40 % after 4 weeks incubation. All tested microalgae can successfully remove the color from TWE with different percentages ratio ranged from 31.15 to 100% after 4 weeks incubation, with priority to both of Nostoc sp. B and Nostoc sp. A which recorded 100% color removal.
● Growing the studied microalgae in TWE water for 4 weeks showed their ability to grow well with different values. However, the highest dry weight of 12.15 mg l-1 was recorded by Nostoc sp. B.
● Results revealed that all the tested microalgae strains decreased both COD, BOD and the EC for the TWE compared to those of the initial values.
Greenhouse work:
Irrigation the Vicia faba plants with the textile wastewater effluent gave the least values of plant height, plant dry weight, root length and root dry weight, (N, P and K), total carbohydrate, crude protein content and (chlorophyll a, b and carotenoids) of Vicia faba plants against when they irrigated with normal tab greenhouse water. The TWE water treated with Nostoc sp. B gave values which were not significantly different from those recorded by normal tab greenhouse water.
Irrigation the Vicia faba plants with the textile wastewater effluent gave the least values of soil available N, P and K against the highest values for soil available N, P and K when they irrigated with normal tab greenhouse water. The TWE water treated with Nostoc sp. B gave values for these parameters which were not significantly different from those recorded by normal tab greenhouse water.
The use of untreated (TWE) (T2) in irrigation of Vicia faba plants led to decrease the rhizosphere soil biological activity of Vicia faba plants compared to the TWE treated by any of Nostoc sp. B or Nostoc sp. A and\or the normal greenhouse tab water for total count bacteria, CO2 evolution, dehydrogenase activity (DHA) and nitrogenase activity (N2-ase).
In conclusion, microalgae can be considered as a pioneer and a promise bio agent used in bioremediation for wastewater especially cyanobacteria.