Bacterial Beta-Glucanase

Introduction

Barley, barley malt, rye, rice and a number of other cereals contain non-starchy polysaccharides. These polysaccharides are linear hemicelluloses (beta-glucans) primarily consisting of beta-1 and beta-1, 3-linked glucopyranose residues forming a beta-glucose polymer. Aqueous solutions of these polysaccharides are very viscose and can cause processing problems when cereals containing them are used.

Description

Zymafilt L-300 is a food grade beta-glucanase [l.U.B. 3.2.1.6; 1-3-(1,3;1,4)-beta-D-Glucan 2(4) glucanohydrolase] obtained by the controlled fermentation of Bacillus subtilis var. The enzyme is an endo-glucanase capable of rapidly hydrolyzing the interior linkages of beta-glucans. Prolonged hydrolysis yields primarily oligosaccharides of three to four glucose units. Zymafilt L-300 rapidly reduces viscosity of aqueous solutions of beta-glucans, increasing filtration rates, reducing stickiness, foam and other handling problems.

Properties

Activity	300 BGU/g
Form	Non-viscous liquid
Color	Light to dark brown
Solubility	Complete miscible with water
Density	(9.60 to 10.43 lb./gal.)

Cofactors and Activators

No activators or cofactors are necessary for the complete activity of the beta-glucanase portion of Zymafilt L-300.

Activity

One Beta-Glucanase Unit (BGU) is that activity which will liberate one micromole of reducing sugar as glucose equivalent under the conditions of the assay. A copy of the Colorimetric Beta-Glucanase Assay (Reducing Sugar Method) is available upon request.

Effect of pH

Zymafilt L-300 has an optimum pH of 6.0 to 7.0 at 40C under the conditions of the Colorimetric Beta-Glucanase Assay. The enzyme demonstrates excellent solution stability over the pH range of 3.5 to 10.0 at 40C. As the temperature is increased, optimum enzyme stability is demonstrated over the pH range of 4.0 to 6.5.

Optimum pH range	pH 6.0 to 7.0
Effective pH range	pH 3.5 to 10.0

Effect of Temperature

Zymafilt L-300 has an optimum temperature of 50C at pH 6.5 under the conditions of the Colorimetric Beta-Glucanase Assay. The enzyme has excellent temperature stability over the temperature range of 50C to 70C.

Optimum Temperature	50C
Effective Temperature	Up to 70C

Other Enzyme Components

In addition to beta-glucanase activity, Zymafilt L-300 is characterized by significant alpha-amylase activity. The alpha-amylase portion is an endoamylase capable of randomly hydrolyzing the predominating alpha-D-1, 4-glucosidic linkages of starch. The alpha-amylase converts starch to soluble dextrins and small quantities of maltose and glucose. The alpha-amylase demonstrates exceptional thermostability and can liquefy starches at temperatures up to 90C.

Substrate

Zymafilt L-300 may be used to hydrolyze the beta-glucans of barley, barley malt, rice, rye and other cereal grains.

Use Level

The exact use level of Zymafilt L-300 varies with process and use conditions. Typically evaluate Zymafilt L-300 at 0.1% to 0.5% based on the weight of unmalted cereal. With malted cereals that contain some beta-glucanase, the dose of Zymafilt L-300 will normally be lower. Initial evaluation should be at 0.01% to 0.03% of the malted cereal weight.

Storage Stability

In sealed containers, under mild ambient conditions, the loss of activity is normally less than 10% over six months. Storage life can be extended by storing under refrigeration at 50C (41F).