Untitled

Hamilton, Lynn; Kelly, Catherine T.; Fogarty, William M.

doi:10.1023/a:1005413816101

Cited by 61 publications

(12 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…IMD434 was purified to homogeneity by acetone precipitation, ion exchange chromatography and hydrophobic interaction chromatography [9]. Similarly, Freer has reported the purification of a raw-starch-degrading extracellullar alpha amylase from Streptococcus bovis JB1 by ion exchange chromatography [10].…”

mentioning

confidence: 99%

Biochemical Characterization of Raw-starch-digesting Alpha Amylase Purified from Bacillus amyloliquefaciens

Gangadharan

Nampoothiri

Sivaramakrishnan

et al. 2008

Appl Biochem Biotechnol

View full text Add to dashboard Cite

Alpha amylase (E.C. 3.2.1.1) of Bacillus amyloliquefaciens produced by submerged fermentation was purified to near homogeneity by ion exchange chromatography. Through the process 38.6-fold increase in purity with a specific activity of 72 U/mg proteins was obtained. The apparent molecular weight of the purified enzyme was found to be 58 kDa by SDS-PAGE. The enzyme was relatively stable between pH 5.0-8.0 and temperature between 50 and 60 degrees C. The enzyme did not show any obligate requirement of metal ions but Ca2+ and Cu2+ enhanced the enzyme activity marginally and the thermostability was enhanced in the presence of Ca2+ ions. The purified enzyme exhibited maximal substrate specificity for amylose and efficiency in digesting various raw starches. The K(m) and V(max) of the enzyme was determined using both amylose and soluble starch as substrate. The analysis of the hydrolyzed products of soluble starch by thin layer chromatography showed the yield of maltosaccharides after 6 h of hydrolysis.

show abstract

mentioning

confidence: 99%

Biochemical Characterization of Raw-starch-digesting Alpha Amylase Purified from Bacillus amyloliquefaciens

Gangadharan

Nampoothiri

Sivaramakrishnan

et al. 2008

Appl Biochem Biotechnol

View full text Add to dashboard Cite

show abstract

“…The pH change observed during the growth of the organisms also affects product stability in the medium [25]. Hamilton et al [26] and Kirti [24] reported that amylases are generally stable over a wide range of pH from 4 to 11. In this study, amylase from Aspergillus sp.…”

Section: Discussionmentioning

confidence: 99%

Characterization of Amylase from Some Aspergillus and Bacillus Species Associated with Cassava Waste Peels

Ayansina¹,

Adelaja²,

Mohammed³

2017

AiM

View full text Add to dashboard Cite

Cassava peels are generated as waste on soils during cassava processing in many tropical countries. This work set out to isolate some microorganisms associated with cassava peel degradation and characterize amylase enzymes responsible for the degradation under some physiological conditions. A total of 30 bacteria was isolated from the peels with Bacillus species occurring the most (46.5%) and Enterobacter species (13.3%) being the next. Frequencies of fungal isolations was Rhizopus sp. (35%); Aspergillus niger (25%); Aspegillus flavus (20%) and Penicillium species (20%). Bacillus cereus, Bacillus substilis Bacillus pumillus, Aspergillus niger and Apergillus flavus were selected and screened for their abilities to produce amylase. Amylase activity was highest at day 4 for B. substilis (39.4 units/ml) and A. flavus (66.1 units/ml); at day 3 for B. cereus (55.6 units/ml) and A. niger (44.6 units/ ml). While maximum amylase activity was obtained at day 6 for B. pumilus (80.2 units/ml). Optimum pH for amylases from the two fungal isolate was 6.0 (A. niger = 53.5 units/ml and A. flavus = 65.4 units/ml). While optimum pH for B.cereus (51.7 units/ ml) and B. pumilus (44.6 units/ml) was 6.5 and for B. substilis (56.1 units/ml) at pH 7.0. Amylase activities increased from 20˚C to 40˚C for amylase from Bacillus sp. and 20˚C to 50˚C for amylase from the Aspergillus sp. after which there was a decline in activities as temperature increased to 80˚C. Effect of heating duration (at 70˚C for 5 minutes) on the amylase showed that A. niger has the highest activity of 127 units/ml. Effect of substrate concentration on amylase activity showed that amylase form A. flavus had the highest activity of 72.2 units/ml at 0.4% substrate concentration. The implications of the findings were discussed.

show abstract

“…However, mostly, submerged fermentation systems were used for production due to the ease in controlling the conditions like pH, temperature, and other environmental conditions. Agricultural wastes were also utilized for amylase production, but for commercial production, synthetic media were used through submerged fermentation [4][5][6][7] . In our previous study 8 , the metal profile of α-amylase was studied which showed that the enzyme produced by this strain was Ca 2+ dependent.…”

Section: Study On Some Properties Of Calcium-dependent A-amylase Frommentioning

confidence: 99%

“…The K m and V max values for α-amylase were determined by linear regression analysis by Lineweaver-Burk plot (double reciprocal plot) using various concentrations of starch (5,10,15,20,25, and 30 mg mL -1 ). The experiments were carried out in triplicate and the activity measured according to the standard assay conditions.…”

Section: Enzyme Kineticsmentioning

confidence: 99%

Study on Some Properties of Calcium-dependent a -Amylase from Bacillus subtilis through Submerged Fermentation of Wheat Bran

Irfan¹

2017

Chem.Biochem.Eng.Q.

View full text Add to dashboard Cite

University of the Punjab new campus Lahore PakistanThis study reveals the production of α-amylase through Bacillus subtilis by submerged fermentation of wheat bran as a substrate. Various conditions were optimized and maximum production was observed at initial medium pH of 7.0, incubation temperature of 35 °C with agitation speed of 140 rpm for 48 h of fermentation period. Peptone, ammonium sulphate and soluble starch favored enzyme production as nitrogen and carbon source, respectively. The crude α-amylase was purified 2.03-fold by column (sephadex G-100) chromatography having specific activity of 480.0 U mg -1 . The purified enzyme had molecular mass of 54.18 kDa as determined by 12 % SDS-PAGE. The optimum pH and temperature of the enzyme was 8.5 and 60 °C, respectively. Ca 2+ played an important role in the stability of the enzyme retaining relative activity of 87 % and 67 % at pH 9.5 and 80 °C, revealing the Ca 2+ dependency respectively. The enzyme was highly stable towards surfactants and oxidizing agents. Kinetic study indicated that the enzyme exhibit K m and V max value of 4.4 mg mL -1 and 714.2 U mL -1 using soluble starch as a substrate respectively.

show abstract

Untitled

Cited by 61 publications

References 9 publications

Biochemical Characterization of Raw-starch-digesting Alpha Amylase Purified from Bacillus amyloliquefaciens

Biochemical Characterization of Raw-starch-digesting Alpha Amylase Purified from Bacillus amyloliquefaciens

Characterization of Amylase from Some Aspergillus and Bacillus Species Associated with Cassava Waste Peels

Study on Some Properties of Calcium-dependent a -Amylase from Bacillus subtilis through Submerged Fermentation of Wheat Bran

Contact Info

Product

Resources

About