1.Purification and Characterization of Intracellular Cellulase from Aspergillus oryzae ITCC-4857.01.
Most Ferdousi BEGUM ; Nurul ABSAR
Mycobiology 2009;37(2):121-127
Purification and characterization of intracellular cellulase produced by A. oryzae ITCC-4857.01 are reported. The enzyme was purified by ion-exchange chromatography using DEAE-cellulose followed by Gel filtration. The purification achieved was 41 fold from the crude extract with yield of 27%. The purified enzyme showed single band on poly acrylamide gel. The molecular weight as determined by SDS-PAGE and gel filtration was 38 KDa and 38.6 KDa respectively and contained only one subunit. The enzyme is glycoprotien as nature and contained 0.67% neutral sugar. The apparent Km value of the enzyme against cellulose was 0.83%. The enzyme showed the highest relative ativities on CMC followed by avicel, salicin and filter paper. The optimum pH of activity was 5.5 and very slight activity was observed at or above pH 7.5 as well as bellow pH 3.5. The optimum tempreture of the activity was 45degrees C and the highest activity was exhibited in 35 to 45degrees C. The enzyme lost their activities almost completely (95~100%) at 80 degrees C or above and as well as bellow 25degrees C.
Acrylamide
;
Aspergillus
;
Aspergillus oryzae
;
Benzyl Alcohols
;
Cellulase
;
Cellulose
;
Chromatography, DEAE-Cellulose
;
Chromatography, Gel
;
Chromatography, Ion Exchange
;
DEAE-Cellulose
;
Electrophoresis, Polyacrylamide Gel
;
Glucosides
;
Hydrogen-Ion Concentration
;
Molecular Weight
;
Oryza
2.Study of antimicrobial activities of chitinases from a potato prototype cultivated in Bangladesh
Syed Rashel Kabir ; Md. Azizul Haque ; Md. Nurujjaman ; Imtiaj Hasan ; Md. Abu Zubair ; Md. Robiul Hassan Chowdhury ; Md. Belal Uddin ; Narayan Roy ; Md. Kamrul Islam ; Nurul Absar
Malaysian Journal of Microbiology 2011;7(2):92-96
Chitinases (designated as SPCs) were isolated from „Shilbilati‟ potatoes, a potato prototype cultivated in Bangladesh by affinity chromatography on a chitin column. SPCs agglutinated rat erythrocytes at the minimum concentration of 7 μg/mL and showed toxicity against brine shrimp nauplii with the LC50 value of 20 μg/mL. The chitinases also agglutinated seven bacterial strains among the twelve as studied. Pseudomonas aeruginosa, Bacillus subtilis and Salmonella typhi were the most sensitive towards the SPCs and were agglutinated at 1.2, 2.5 and 5.0 μg/mL protein concentrations respectively. Antibacterial tests demonstrated that SPCs showed inhibitory activity against the pathogenic bacteria Staphylococcus aureus, Bacillus subtilis and Salmonella typhi. Antifungal activity was investigated by the disc diffusion method. Five fungal species (Candida albicans, Aspergillus niger, Fusarium vasinfectum, Aspergillus fumigatus and Aspergillus flavus) and two fungal genus (Penicillium and Mucor sp.) were examined in the assay. SPCs showed antifungal activity against Candida albicans, Fusarium vasinfectum and Penicillium sp.