Limits...
Molecular Identification of a Newly Isolated Bacillus subtilis BI19 and Optimization of Production Conditions for Enhanced Production of Extracellular Amylase.

Dash BK, Rahman MM, Sarker PK - Biomed Res Int (2015)

Bottom Line: Rice flour (1.25%) as a cheap natural carbon source was found to induce amylase production mostly.Addition of surfactants like Tween 80 (0.25 g/L) and sodium lauryl sulfate (0.2 g/L) resulted in 28% and 15% increase in enzyme production, respectively.These results suggest that B. subtilis BI19 could be exploited for production of amylase at relatively low cost and time.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology and Genetic Engineering, Faculty of Applied Science and Technology, Islamic University, Kushtia 7003, Bangladesh ; Department of Genetic Engineering and Biotechnology, Faculty of Biological Science and Technology, Jessore University of Science and Technology, Jessore 7408, Bangladesh.

ABSTRACT
A study was carried out with a newly isolated bacterial strain yielding extracellular amylase. The phylogenetic tree constructed on the basis of 16S rDNA gene sequences revealed this strain as clustered with the closest members of Bacillus sp. and identified as Bacillus subtilis BI19. The effect of various fermentation conditions on amylase production through shake-flask culture was investigated. Rice flour (1.25%) as a cheap natural carbon source was found to induce amylase production mostly. A combination of peptone and tryptone as organic and ammonium sulfate as inorganic nitrogen sources gave highest yield. Maximum production was obtained after 24 h of incubation at 37 °C with an initial medium pH 8.0. Addition of surfactants like Tween 80 (0.25 g/L) and sodium lauryl sulfate (0.2 g/L) resulted in 28% and 15% increase in enzyme production, respectively. Amylase production was 3.06 times higher when optimized production conditions were used. Optimum reaction temperature and pH for crude amylase activity were 50 °C and 6.0, respectively. The crude enzyme showed activity and stability over a fair range of temperature and pH. These results suggest that B. subtilis BI19 could be exploited for production of amylase at relatively low cost and time.

No MeSH data available.


Related in: MedlinePlus

Partial characterization of crude amylase. (a) Effect of temperature on activity of crude amylase. (b) Effect of temperature on stability of crude amylase. (c) Effect of pH on activity of crude amylase. (d) Effect of pH on stability of crude amylase.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4477212&req=5

fig5: Partial characterization of crude amylase. (a) Effect of temperature on activity of crude amylase. (b) Effect of temperature on stability of crude amylase. (c) Effect of pH on activity of crude amylase. (d) Effect of pH on stability of crude amylase.

Mentions: The effect of temperature on amylase activity was assayed at different temperatures ranging from 30 to 90°C at optimum pH 8.0. The optimum temperature for amylase activity was found to be between 40 and 60°C (Figure 5(a)). Amylase retained 100% relative activity when incubated at 50°C and, as temperature increased from 60 to 80°C, the activity was swiftly declined. At 80°C, the activity was the least (12%) and no activity was found at 90°C. These findings are comparable with that reported for the production of α-amylase using B. amyloliquefaciens by Demirkan (2011) [48]. In our study, crude amylase was heated at different temperatures for 1 h followed by testing its activity. The results showed that room temperature (25°C) was suitable for a long term stability of enzyme activity retaining 100% relative activity (Figure 5(b)). The enzyme retained above 60% relative activity even after heating at 50°C for 1 h. Thus these results concluded that the crude enzyme is moderately temperature stable. These findings agree with that reported by Yang and Liu, 2004 [49].


Molecular Identification of a Newly Isolated Bacillus subtilis BI19 and Optimization of Production Conditions for Enhanced Production of Extracellular Amylase.

Dash BK, Rahman MM, Sarker PK - Biomed Res Int (2015)

Partial characterization of crude amylase. (a) Effect of temperature on activity of crude amylase. (b) Effect of temperature on stability of crude amylase. (c) Effect of pH on activity of crude amylase. (d) Effect of pH on stability of crude amylase.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4477212&req=5

fig5: Partial characterization of crude amylase. (a) Effect of temperature on activity of crude amylase. (b) Effect of temperature on stability of crude amylase. (c) Effect of pH on activity of crude amylase. (d) Effect of pH on stability of crude amylase.
Mentions: The effect of temperature on amylase activity was assayed at different temperatures ranging from 30 to 90°C at optimum pH 8.0. The optimum temperature for amylase activity was found to be between 40 and 60°C (Figure 5(a)). Amylase retained 100% relative activity when incubated at 50°C and, as temperature increased from 60 to 80°C, the activity was swiftly declined. At 80°C, the activity was the least (12%) and no activity was found at 90°C. These findings are comparable with that reported for the production of α-amylase using B. amyloliquefaciens by Demirkan (2011) [48]. In our study, crude amylase was heated at different temperatures for 1 h followed by testing its activity. The results showed that room temperature (25°C) was suitable for a long term stability of enzyme activity retaining 100% relative activity (Figure 5(b)). The enzyme retained above 60% relative activity even after heating at 50°C for 1 h. Thus these results concluded that the crude enzyme is moderately temperature stable. These findings agree with that reported by Yang and Liu, 2004 [49].

Bottom Line: Rice flour (1.25%) as a cheap natural carbon source was found to induce amylase production mostly.Addition of surfactants like Tween 80 (0.25 g/L) and sodium lauryl sulfate (0.2 g/L) resulted in 28% and 15% increase in enzyme production, respectively.These results suggest that B. subtilis BI19 could be exploited for production of amylase at relatively low cost and time.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology and Genetic Engineering, Faculty of Applied Science and Technology, Islamic University, Kushtia 7003, Bangladesh ; Department of Genetic Engineering and Biotechnology, Faculty of Biological Science and Technology, Jessore University of Science and Technology, Jessore 7408, Bangladesh.

ABSTRACT
A study was carried out with a newly isolated bacterial strain yielding extracellular amylase. The phylogenetic tree constructed on the basis of 16S rDNA gene sequences revealed this strain as clustered with the closest members of Bacillus sp. and identified as Bacillus subtilis BI19. The effect of various fermentation conditions on amylase production through shake-flask culture was investigated. Rice flour (1.25%) as a cheap natural carbon source was found to induce amylase production mostly. A combination of peptone and tryptone as organic and ammonium sulfate as inorganic nitrogen sources gave highest yield. Maximum production was obtained after 24 h of incubation at 37 °C with an initial medium pH 8.0. Addition of surfactants like Tween 80 (0.25 g/L) and sodium lauryl sulfate (0.2 g/L) resulted in 28% and 15% increase in enzyme production, respectively. Amylase production was 3.06 times higher when optimized production conditions were used. Optimum reaction temperature and pH for crude amylase activity were 50 °C and 6.0, respectively. The crude enzyme showed activity and stability over a fair range of temperature and pH. These results suggest that B. subtilis BI19 could be exploited for production of amylase at relatively low cost and time.

No MeSH data available.


Related in: MedlinePlus