الفهرس 
Importance of the textile industry in EgyptOnly 14 pages are availabe for public view
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Abstract
This study was carried out to investigate the potentiality of some isolated fungi to decolorize synthetic textile dyes. Nine species of fungi belong to five genera were isolated from textile waste water which collected as effluent samples from Egypt Company for textile industry at Mahala El- Kobra, El-Gharbia Governorate, Egypt. All isolated fungi were identified morphologically under light microscope at Mag. 40x. Yeast species identified biochemically using API 20 C AUX (bioMérieux) identification kit, and the resultant yeasts colonies were biochemically identified as Candida albicans 1 and Rhodotorula mucilaginosa 1. While, identification of selected filamentous fungus was confirmed using 18S rRNA gene PCR and the resultant data showed that filamentous fungus was Penicillium chrysogenum MH745129. On other hand Pleurotus eryngii somycel France was obtained from Mushroom Laboratory Culture Collection (MLCC), El-Giza, Egypt and used as standard decolorizing fungal strain due to its ability to decolorize and degrade dyes by enzymes. The results in the present study indicated that all fungal isolates had the ability to decolorize textile dyes with different decolorization percentage ranging between 9.6 % and 98 % after 7 days of incubation. P. chrysogenum MH745129 was chosen because the Aspergillus flavus produce aflatoxins which measured and reached to 9 ppm. P. chrysogenum MH745129 removed about 93.2, 86.3 and 87.4 % of reactive dyes Blue 21, Yellow 160 and Orange 122 respectively, also decolorization percentage of direct Congo red, direct Yellow 5G, acid Eriochrome Black T and acid Methyl orange were 91.1, 43.3, 89.4 and 12.9 % respectively. Decolorization process and growth of the fungus were optimized by studying the effect physiochemical parameters, which the Penicillium chrysogenum MH745129 gave maximum decolorization of 50 mg/l Blue 21 dye in Czapek’s dox media with 5.5 pH and when incubated in shaking incubator at 150 rpm and 30oC after 7 days of incubation which the decolorization percentage reached to 96 % approximately. Mycelia of Pencillium chrysogenum MH745129 after treatment of reactive Blue 21 dye was examined microscopically and compared with mycelia of higher fungus Pleurotus eryngii. It was found that large part of mycelia take blue color and other part of mycelia were colorless, this indicated that P. chrysogenum MH745129 had two mechanism in decolorization of Blue 21 dye by bio-sorption process through uptake and accumulate dye inside the fungal mycelia and biodegradation process which can degrade dye but with low percentage. While the mycelia of P. eryngii appear colorless, in this case the dominant mechanism for decolorization of Blue 21 dye by P. eryngii would be the biodegradation of the dye molecules by releasing enzymes responsible for degradation. After decolorization of Blue 21 dye using free and immobilized P. chrysogenum MH745129 and P. eryngii on different substrate like rice straw, wheat straw, sugar cane waste and wheat bran, the results indicated that the immobilization process improve the efficiency of decolorization than using them in free form. It was clearly noticed that immobilized P. chrysogenum MH745129 and P. eryngii on sugar cane waste had significant ability to decolorize Blue 21 dye with efficiency reached to 66.83 and 83.2 % after 72 h of incubation, while efficiency reached to 38.4 and 50.8 % using them in free form. In this study the laccase, Mn peroxidase, peroxidase and catechol oxidase enzymes activity screened in P. eryngii cultivated on sugar cane waste, which P. eryngii produce high amount of lacasse enzyme compared to other enzyme which the maximum activity of laccase, Mn peroxidase, peroxidase and catechol oxidase enzymes were 4.55 1.37, 0.023, 0.035 U/min/ml respectively after 12 days of cultivation. On other hand the enzyme activity was low in P. chrysogenum MH745129 compared to the enzyme activity of P. eryngii, but P. chrysogenum MH745129 produce amount of laccase enzyme higher than other enzymes and the maximum activity of laccase and Mn peroxidase reached to 0.153 and 0.055 U/min/ml after 5 days of cultivation on sugar cane waste. In this study it was clearly noticed that P. Eryngii immobilized on sugar cane waste had the highest ability to purify textile waste water (textile effluent) as all measured parameters were significantly decreased. Decolorization efficiency of dye in effluent reached to 96.16 %, treatment efficiency of COD, BOD, EC, TSS and TDS were 90, 85.11, 38, 79 and 37.19 % respectively. On other hand immobilized P. chrysogenum MH745129 had ability to purify waste water which the decolorization of dye in effluent reached to 84.76 %, while COD, BOD, EC, TSS and TDS decreased significantly and reached to 84.6, 82.32, 29.4, 72.12 and 24.79 % respectively. Artemia salina larvae were used for the toxicity assessment of treated textile effluent with immobilized Pleurotus eryngii and Pencillium chrysogenum MH745129. The results in this study indicated that the toxicity of the textile effluent was decreased after biological treatment which the survival rate of A. salina in treated textile effluent by immobilized P. eryngii was 100 % at 24 and 48 h but survival rate of A. salina in treated textile effluent by immobilized P. chrysogenum MH745129 was 100 and 90 % after 24 and 48 h comparing to survival rate in untreated textile effluent was zero after 48 h. Concerning the effect of irrigation by untreated and treated textile waste water on the growth of Basil plant (Ocimum basilicum). The results showed that irrigation with treated textile waste water with immobilized Pleurotus eryngii and Pencillium chrysogenum MH745129 on sugar cane waste induced and increased the growth of the Basil plant as compared with irrigation by the untreated one. Treated waste water gave similar results in physical parameters as well as pigmentation, protein and carbohydrate contents of Basil plant to those of plants irrigated with tap water. Finally, immobilized microorganisms for textile waste water treatment provide low costs and energy. Waste water treatment can thus to protect wildlife and enhance environmental quality by the production of high-quality effluent with low toxicity that can be used for irrigation of some plants.