• Food Science and Biotechnology
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• v.14 no.5
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• pp.681-684
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• 2005

A maltopentaose-producing amylase (G5-amylase) from Bacillus megaterium KSM B-404 was applied to retard bread retrogradation. Retrogradation rates were determined by differential scanning calorimetry. Gel permeation chromatography determined changes in maltooligosaccharide composition and the molecular weight profiles of carbohydrate tractions. The baking process produced maltopentaose and maltotriose by the hydrolysis of starch molecules into small units. Amylose and amylopectin degradation as well as maltooligosaccharides produced by the enzyme were likely responsible for retarding starch retrogradation. Overall, addition of G5-amylase reduced the starch retrogradation rate, and was as effective as Novamyl(R), a commercial enzyme.

• KSBB Journal
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• v.16 no.3
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• pp.246-252
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• 2001

We isolated a bacterium that produces an extracellular maltopentaose(G5)-forming amylase from amylose and soluble starch. The bacterium was identified and assigned as a Bacillus sp. AIR-5. The amylase did not hydrolyze maltose, maltotriose, maltotetraose or maltopentaose. Optimum medium composition for maltopentaose production in flask culture was 2%(w/v) soluble starch, 0.4%(w/v) tryptone, 0.5%(w/v) NaCl, 0.5%(w/v) K$_2$HPO$_4$, and 3 mM CaCl$_2$at pH 8.0, 28$^{\circ}C$. The highest yield for maltopentaose production in this condition was 6.45 g/L and was 32.55% of theoretical yield.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.633-637
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• 1994

A bacterial strain KSM-35 producing maltotetraose forming amylase was isolated from compost and identified as Streptomyces based on its morphological, cultural, and physiological characteristics. The amylase from Streptomyces sp. KSM-35 culture filtrate was purified by ammonium sulfate precipitation, followed by the liquid chromatographic procedures using DEAE-Toyo pearl and sephadex G-100 with 27.1% activity recovery. The molecular weight of the enzyme was estimated to be 50,000 and the isoelectric point 4.3. The main product by the amylase from soluble starch was maltotetraose which accounted for 56% of all the oligosaccharides detected after 26 hrs of reaction. Maltose (20%o) and maltotriose (16%) were the next important byproducts while glucose and maltopentaose were detected as traces.