Browsing by Subject "Cellulase"
  • Item
    Isolation and purification of cellulase from alkaline-tolerant Bacillus subtilis
    (Universitas Katolik Soegijapranata, 2014-09) Passanee Thongthawee ; Malinee Sriariyanun ; Kraipat Cheenkachorn ; Jirapa Phetsom ; Patchanee Yasurin
    Lignocellulosic biomass is one of the most abundant renewable resource in the world. It has high potential to be used as material for biorefinery process because it yields fermentable sugar that can be converted to various bioproducts via microorganism functions. To make the biorefinery process success, the efficient hydrolysis process is needed to be improved to release the maximum amounts of sugars from lignocellulosic biomass. Natural environment is an important source to find an efficient cellulase producing bacteria. Previously, an alkaline-tolerant cellulase-producing bacterium, Bacillus subtilis strain MSB9, was screened and isolated from Botanic garden in Mahasarakham province, Thailand. In this study, we focused on the purification and characterization of cellulase enzyme produced by B. subtilis strain MSB9. The crude cellulase enzyme was partially purified and concentrated by ammonium sulfate precipitation and fractionated by using size exclusion chromatography using sephacryl S-100 HR column. Two of purified cellulase have relative molecular mass of 35 and 45 kDa, as determined by SDS-PAGE combined with CMC-zymogram.
  • Item
    Production, purification and characterization of an ionic liquid tolerant cellulase from Bacillus sp. isolated from rice paddy field soil
    ( 2015) Patchanee Yasurin
    Background: Lignocellulosic biomass is a renewable, abundant, and inexpensive resource for biorefining process to produce biofuel and valuable chemicals. To make the process become feasible, it requires the use of both efficient pretreatment and hydrolysis enzymes to generate fermentable sugars. Ionic liquid (IL) pretreatment has been demonstrated to be a promising method to enhance the saccharification of biomass by cellulase enzyme; however, the remaining IL in the hydrolysis buffer strongly inhibits the function of cellulase. This study aimed to isolate a potential IL-tolerant cellulase producing bacterium to be applied in biorefining process. Result: One Bacillus sp., MSL2 strain, obtained from rice paddy field soil was isolated based on screening of cellulase assay. Its cellulase enzyme was purified and fractionated using a size exclusion chromatography. The molecular weight of purified cellulose was 48 kDa as revealed by SDS-PAGE and zymogram analysis. In the presence of the IL, 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) concentration of 1 M, the cellulase activity retained 77.7% of non-IL condition. In addition, the optimum temperature and pH of the enzyme is 50°C and pH 6.0, respectively. However, this cellulase retained its activity more than 90% at 55°C, and pH 4.0. Kinetic analysis of purified enzyme showed that the Km and Vmax were 0.8 mg/mL and 1000 μM/min, respectively. Conclusion: The characterization of cellulase produced from MSL2 strain was described here. These properties of cellulase made this bacterial strain become potential to be used in the biorefining process.
  • Item
    Purification and identification of bacterial cellulase activity of Bacillus subtilis W48 for biofuel production
    (School of Biotechnology, Assumption University of Thailand, 2014-07) Patchanee Yasurin
    Lignocellulosic biomass is a renewable, inexpensive, and abundant resource with high potential for biofuel production to implement the sustainable energy worldwide. An important key of biofuel production is the hydrolysis of lignocellulosic biomass to fermentable sugars. Screening for a novel cellulase, as a biocatalyst, is challenge for development of biofuel production to be the economic and environmental friendly process. Natural environment is an important source to find an efficient cellulase producing bacteria. Previously, Bacillus subtilis strain W48 was screened and isolated from rainforest park at Assumption University, Bangkok, Thailand. In this study, we focused on the purification and characterization of cellulase enzyme produced by B. subtilis strain W48. The crude cellulase enzyme was collected by culture grown at 45°C in carboxy-methyl-cellulose (CMC) media. Then, it is concentrated by ammonium sulfate precipitation and fractionated by using size exclusion chromatography using sephacryl S- 100 HR column. In this study, the fractions that has highest CMCase activity (0.017 mg/ml), as endoglucanase, and FPase activity (0.013 mg/ml), exoglucanase, are fraction no. 13 and 11, respectively.