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Journal : Microbiology Indonesia

The Process of Xylanase Production from Bacillus pumilus RXAIII-5 NUR RICHANA; TUN TEDJA IRAWADI; M. ANWAR NUR; ILLAH SAILAH; KHASWAR SYAMSU
Microbiology Indonesia Vol. 1 No. 2 (2007): August 2007
Publisher : Indonesian Society for microbiology

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (324.944 KB) | DOI: 10.5454/mi.1.2.6

Abstract

The optimum conditions for the growth of Bacillus pumilus RXAIII-5 (a potential xylanase producer) were sought, these included temperature, pH, aeration, and agitation of the culture batch. Afterwards a mathematical model based on the parameter of cultivation kinetics was formulated. At the same time, the rheology of the fluid used for bacterial cultivation in a bioreactor was studied. The data obtained was used for estimating the ‘scaling up’ of enzyme production. The results of the study indicate that the optimum condition for processing in 50 ml Erlenmeyer flask are used temperature of 35 oC (308oK), pH 7, and an agitation rate of 140 rpm. The highest xylanase activity and its specific activity are 297.132 U.ml-1 and 655.32 U.g-1protein, respectively. Subsequent experiments in a bioreactor using all of the experiment parameters mentioned above, except for the agitation rate, shows that the results are as follows. The highest specific growth was at 0.082 hour-1 at an aeration and agitation rate of 0.5 vvm and 150 rpm, respectively. Based on the data of the cultivation kinetics, the optimum conditions for the fermentation in Biostat 2L-bioreactor is 1 vvm and 200 rpm of aeration and agitation, respectively . The efficiency of substrate (Yp/s) and of cell biomass (Yp/x) to produce xylanase is 50.744 U.g-1 and 43.906 U.g-1, respectively. The efficiency of substrate to cell production (Yx/s) is 1.178g.g-1. The liquid cultivation-medium has non-Newtonian properties. Based on a mathematical model it is found that the consistency index (k constant) and index of liquid behavior (n value) are 0.179 g.cm-1.second-1 and 0.3212, respectively. Becouse the value of 0
Isolation and Characterization of Antimicrobial Substance from Marine Streptomyces sp. ROFIQ SUNARYANTO; BAMBANG MARWOTO; TUN TEDJA IRAWADI; ZAINAL ALIM MAS'UD; LIESBETINI HARTOTO
Microbiology Indonesia Vol. 4 No. 2 (2010): August 2010
Publisher : Indonesian Society for microbiology

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (6996.369 KB) | DOI: 10.5454/mi.4.2.7

Abstract

Isolation and purification of antimicrobial active substance produced by marine Actinomycetes has been carried out. Marine sediment samples were obtained from six different places at Banten West Coast. Isolation was conducted using two pretreatment methods, acid and heat shock pre-treatment. A total of 29 Actinomycetes isolates were obtained from the various sediment samples collected, then tested for antimicrobial activity against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC25923, Pseudomonas aeruginosa ATCC27853, Bacillus subtilis ATCC 66923, Candida albicans BIOMCC00122, and Aspergillus niger BIOMCC00134. Among the isolates, isolate A11 was the most activity to Gram-positive and Gram-negative bacteria, and morphological observation and identification using 16S rRNA showed that the isolate was similar to Streptomyces sp. Production of active compound from A11 isolate used yeast peptone medium. Purification of active compounds was carried out using silica-gel-column chromatography and preparative HPLC. A single peak of active compounds was detected by HPLC, which showed a retention time of 8.35 min and maximum absorbance in UV visible at 210 nm and 274.5 nm respectively.