Phenylalanine 314 is essential for the activity of maltogenic amylase from Corallococcus sp. EGB

AbstractThe cyclodextrin glucanotransferase from Paenibacillus pabuli US132 (US132 CGTase) was engineered using a rational approach in an attempt to provide it with anti-staling properties comparable to those of the commercial maltogenic amylase (Novamyl). The study aimed to concurrently decrease the cyclization activity and increase the hydrolytic activity of US132 CGTase. A five-residue loop (PAGFS) was inserted, alone or with the substitution of essential residues for cyclization (G180, L194 and Y195), mimicking the case of Novamyl. The findings indicate that, unlike the case of the CGTase of Thermoanerobacterium thermosulfurigenes strain EM1 whose initial high hydrolytic activity was exceptional, these mutations completely abolished the cyclization and hydrolytic activities of the US132 CGTase. This suggests that those mutations are not able to convert conventional CGTases, whose hydrolytic activities are very weak, into hydrolases. Accordingly, and for the first time, a structural barrier at subsite −3 was advanced as an influential factor which might explain the low hydrolytic activity of conventional CGTases.

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A new maltogenic amylase from Bacillus licheniformis R-53 significantly improves bread quality and extends shelf life

Food Chemistry ◽

10.1016/j.foodchem.2020.128599 ◽

2020 ◽

pp. 128599

Author(s):

Yingqi Ruan ◽

Yan Xu ◽

Wenchi Zhang ◽

Rongzhen Zhang

Keyword(s):

Shelf Life ◽

Bacillus Licheniformis ◽

Bread Quality ◽

Maltogenic Amylase

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Effects of enzymes and hydrocolloids on physical, sensory, and shelf-life properties of wheat bread

Chemical Papers ◽

10.2478/s11696-012-0286-4 ◽

2013 ◽

Vol 67 (3) ◽

Cited By ~ 8

Author(s):

Ľubomír Mikuš ◽

Mária Kováčová ◽

Ladislav Dodok ◽

Alžbeta Medveďová ◽

Lucia Mikušová ◽

...

Keyword(s):

Shelf Life ◽

Xanthan Gum ◽

Guar Gum ◽

Sensory Properties ◽

Life Extension ◽

Wheat Bread ◽

Bakery Product ◽

White Wheat ◽

Activity Test ◽

Maltogenic Amylase

AbstractThis study compares two types of enzymes: maltogenic amylase (Novamyl 10000 BG) and lipase (Lipopan F BG, Lipopan Xtra BG), both separately and in combination, and seven hydrocolloids (guar gum, xanthan gum, carrageenan, β-glucan, carob gum, and carboxymethyl cellulose (CMC)) on the physical and sensory properties of a bakery product (white wheat bread). Their effect was observed on the baking characteristics of volume, specific volume, shape, mass, shelf-life (penetration and water activity test), and overall taste. The best results in shelf-life extension from the hydrocolloids were shown by β-glucan, a combination of xanthan gum + carrageenan and guar gum. From the enzymes, the best results were achieved with Lipopan Xtra BG and Novamyl 10000 BG + Lipopan F BG combination. The sensory properties (e.g. taste, colour, shape, aroma, elasticity, hardness) were evaluated by ten trained panellists, holding certification in sensory analysis. β-Glucan and Novamyl 10000 BG + Lipopan F BG combination increased the bread volume significantly and also were deemed to afford the most favourable taste.

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