Characterization of alkaline xylanases from Bacillus pumilus

Abstract

Alkaline xylanases produced by four different strains of Bacillus pumilus were characterized. The optimal pH and temperature were pH 9.0 and 60ºC for strain 13 a , and pH 8.0 and 55ºC for strains 5 2 , 5 14 , and 4 a. Under these conditions the following activities were found after 10 min in the presence of 1% xylan (birchwood): 328 U.ml-1 , 131 U.ml-1 , 90 U.ml-1 , and 167 U.ml-1 , respectively, for the four strains. The enzymes were stable at 40ºC, with 40% of the xylanase activity remaining after 2 hours for the enzymes of strain 5 2 and 60% for the other three strains. Stability at 50ºC was improved by addition of glycerol. Taking into account the conditions under which kraft pulps are bleached during the manufacture of paper, xylanases from B. pumilus exhibit favorable potential for application to bleaching in the paper making process.

Screening and identification of xylanase-producing bacteria from Thai soils

“…has been reported (Archana and Satyanarayana, 2003;Beg et al, 2001;Breccia et al, 1999;Chang et al, 2004;Duarte et al, 2000;Kim et al, 2005;Rapp and Wagner, 1986;Rawashdeh et al, 2005;Rivas et al, 2004;Sunna et al,1997). In this study, a lot of Microbacterium barkeri, Bacillus niabensis, B. funiculus, B. megaterium, Pseudoxanthomonas suwonensis, Cupriavidus gilardii, and Rhodococcus rhodochrous strains could produce xylanase as mentioned above.…”

Use of Bacillus pumilus CBMAI 0008 and Paenibacillus sp. CBMAI 868 for colour removal from paper mill effluent

“…Bacillus pumilus CBMAI 0008 and Paenibacillus sp. CBMAI 868 previously isolated, respectively, from wood decomposition material and paper mill effluent were identified by the Coleção Brasileira de Microrganismos de Ambiente e Indústria -CBMAI and are able to produce alkaline enzymes under thermophilic conditions, including xylanases and manganese-dependent peroxidase (1,2,3,8,10). In this study we evaluated the ability of these bacteria for colour removal of the paper mill effluent.…”

Atividade de extratos de Arrabidaea chica (Humb. & Bonpl.) Verlot obtidos por processos biotecnológicos sobre a proliferação de fibroblastos e células tumorais humanas

“…As outras duas antocianidinas (6,7,3,4´-tetra-hidoxi-5-metoxiflavilio e 6,7,4´-tri-hidroxi-5-metoxiflavilio) não sofreram alterações significativas após processo de fermentação das folhas. 15 Contatou-se que o processo de hidrolise enzimático favoreceu o aumento do rendimento global da carajiruna (Figura 3).…”