Production of Bacillus licheniformis ATCC 21415 alkaline protease in batch, repeated batch and continuous culture

Bacillus licheniformis ATCC 21415 cells were immobilized on different carriers using different methods of immobilization including physical adsorption, covalent binding, ionic binding and entrapment. The immobilized cells were prepared by covalent binding on wool (as a new carrier) through 1% glutaraldehyde had the highest enzyme activity (9.0 U/mL) with the highest specific productivity (6.17 U/g wet cells/h). Alkaline protease production and the stability of biocatalyst were investigated in both free and immobilized cells. The results showed that the immobilized cells were more efficient for enzyme production by repeated batch fermentation (5 cycles, 480 h) with 57% residual activity whereas the free cells retained 35% after 2 cycles. In continuous production the highest enzyme activity (9.9 U/mL) was obtained at a dilution rate of 0.1/h while the highest enzyme yield (763.6 U/h) and the highest reactor productivity (3.32 U/mL/h) were attained at a dilution rate of 0.4/h. Packed-bed bioreactor was a successful method for continuous production of alkaline protease for a long time (168 h) with 53% relative activity. The bioreactor affected the highest specific productivity (118.2 U/g wet cells/h) which was 12-24 times higher than other systems of enzyme production.

Preparation and properties of xylanase produced by penicillium funiculosum 258

Some properties of the crude lyophilized xylanase produced by shaken cultures of Penicillium funiculosum 258 using sugar cane bagasse xylan were studied. The enzyme showed its maximal activity at pH 5 and 50C. Maximal enzymes activity was reached on using 35 mg of xylan and 0.25 mg enzymes protein indicating an enzyme: substrate ratio of 1: 140. Thus, the enzyme could release 26.4 times its own weight of reducing sugars in 20 minutes at 50C and pH 5. However, saccharification of xylan was maximal [43.3%] on using enzyme/substrate ratio of 1: 624. The enzyme was more stable above pH 5 than below it. Partial purification of the lyophilized enzyme preparation was achieved by fractional precipitation with ethanol acetone and ammonium sulfate which allowed the recovery of 49.2, 13.3 and 95.9% xylanase activity, respectively. Of the 16 fractions obtained, the fraction salted out at 75% ammonium sulfate saturation was the most active and effected 4.42-fold purification. Besides, the culture filtrate of P. Funiculosum 258 showed feeble beta-xylosidase activity [0.053 U mg protein]

Purification and kinetic studies of xylanase and beta-xylosidase from penicillium funiculosum 258

Purification of xylanase and beta-xylosidase produced by Penicillium funiculosum 258 was achieved by chromatography on Ecteola cellulose Et 11 column using the stepwise elution technique with acetate buffer solution. The column effected 6-3-fold purification of xylanase and 1.88-fold purification for beta-xylosidase. Xylooligosaccharides were the major hydrolysis products by the action of xylanase on xylan. Xylanase was consistently rich in aspartic acid, glutamic acid, serine and threonine residues. Using p-nitrophenyl beta-D-xyloside as a substrate, beta-xylosidease had a Km value of 1.6 mM, a Vmax of 0.02 mu moles mg-1 min-1 and showed its maximal activity at pH 5.5 and 55 degree. In absence of substrate, the enzyme was thermolabile. The pure beta-xylosidase was strongly inhibited by Co+2 and Mg+2 and completely inhibited by 1 mM Mn2+, Hg2+ or 0.05 mM xylose. The enzyme was consistently rich in serine, threonine and histidine residue by contained small proportion of aspartic acid. Both xylanase and beta-xylosidase were devoid of the sulphur-containing amino acids cystine and cysteine

Production of fibrinolytic and proteolytic enzymes by fungi isolated from Egyptian soil

Production of fibrinolytic, caseinase, gelatinase and milk-clotting enzymes by 10 local soil fungal isolates was investigated. Surface cultures enhanced the proteolytic, activities. The age and type of culture influenced the production of the different tested proteolytic enzymes. Cell-free extracts of most fungal cultures showed feeble fibrinolytic activity. Extracellular enzymes showed high FA/CA ratio. Penicillium Chrysogenum H9 in 3-day, old static culture was the most promising as a fibrinolytic producer

Isolation and properties of fibrinolytic enzymes produced by immobilized penicillium chrysogenum H9

Some properties of the crude fibrinolytic enzyme produced by immobilized Penicillium chrysogenum H9 were studied. A para11e1 relationship existed between enzyme concentration fibrinolytic activity up to a level of 0.8 mg/ml. Substrate concentration of 12 mg/ml showed maximal activity. The fibrinolytic enzyme showed an optimum temperature of 45°C for the reaction and a pH optimum of 6.64 upon using sorensen phosphate buffer. Isolation of the fibrinolytic enzymes from the immobilized cultures of Penicillium chrysogenum H9 by fractional precipitation was carried out with various agents. Of all the obtained fractions, that precipitated at 50% ammonium sulphate saturation was the most promising enzyme fraction possessing good thrombolytic properties

Purification and characteristics of pure fibrinolytic enzymes from immobilized penicillium chrysogenum H9

Two fibrinolytic enzymes, A[1][MW 48,000] and A[2]a [MW 39,000], use purified from the culture filtrate of immobilized cells of Penicillium chrysogenum H9. This was achieved by using Sephadex G-150 gel filtration and DEAE-cellulose column chromatography successively. The homogenecity of both enzymes was checked by disc gel-electrophoresis. The pure enzymes were more active on man than on bovine fibrin. They also showed weak caseinase activity. The fibrinolytic enzyme A[2]a was more thermostable than[A]1, and relatively resistant to acidic pH. Iodine, iodo-acetic acid and Hg[+2] ions partially inhibited the activity of both enzymes indicating the lack of -SH groups in their active sites