Sanaa S.H. Sarabana, Amal W. Abou El- Khair and Khadiga I.M. El-Gabry( 2014). Fungi are Unique Cellulase-and Zylanase-Producing MicrobiotaMiddle East Journal of Agriculture Research, 3(3): 560-568, 2014 ISSN 2077-4605
Abstract: The objective of this study is to screen cellulose- and zylan-hydrolytic fungi in samples collected from different rotten agricultural wastes (strawberry, grapes, fig and artichoke), decomposed wood and compost. One hundred and seven isolates were secured on cellulose or zylan containing medium. They were tested for their ability to analyze both of cellulose and zylan. Sixty-nine isolates were positive for cellulases and zylanase activities. Fifteen isolates were found to be the most effective producers of cellulolytic enzymes. Seven isolates were identified as Fusarium oxysporum-I, Aspergillus versicolor-1 and 2, Aspergillus oryzae, Penicillium citrinum, Penicillium brevicompactum and Mucor indicus. These isolates were compared with some other fungi known to produce cellulases and zylanase. The latter are Phanerochaete chrysosporium, Pleurotus ostreatus, Fusarium oxysporum, and Rhizoctonia solani. Phanerochaete chrysosporium, Pleurotus ostreatus and Fusarium oxysporum were the superior producers of cellulolytic enzymes. To study the cellulases and zylanase
activities, corncobs (a recycled agricultural waste) and carboxymethylcellulose (CMC) (an intermediate cellulolytic product) were selected and added to Mandel's medium, as carbon sources. The activity of filter paper cellulose activity (FP-ase) of all strains, on the medium containing corn cobs, was higher than its activity on the medium containing CMC. On corn cobs containing medium, P. previcompactum and A. versicolor-2 gave the highest FP-ase activities (7.44 and 7.29 U/ml, respectively). While on CMC containing medium, A. versicolor-1 was the most efficient as, it gave 15.7 U/ml. The activity of CMC-ase was the highest when produced by A. versicolor-2 and A. versicolor-1 on the medium containing corn cobs, which gave 32 and 27.55 IU/ml, respectively. While on the medium containing CMC, A. versicolor-1 gave 33.4 IU/ml. In respect to β- glucosidase, Pleurotus ostreatus was the superior on the medium containing CMC, it gave 570.64 IU/ml. followed by F. oxysporum-I, F. oxysporum, A. oryzae, (353.57, 349.45 and 343.96 IU/ml. respectively). The isolate Mucor indicus gave 325.45 IU/ml on the medium containing corn cobs. Regarding zylanase, its activity tested the isolates was higher than its activity among the known strains on both medium containing corn cobs and CMC. A. versicolor-2 was the superior in its production; it gave 35.24 IU/ml.
Keywords: (Cellulase; zylanase, Phanerochaete sp., Pleurotus sp., Fusarium sp., Aspergillus sp., Penicillium sp., Mucor indicus.)
