Azo-Barley Glucan is supplied at 1% w/v. This can be used in an agar plate. It is provided unbuffered but with 0.2% sodium azide as a preservative.  Perhaps a concentration in the gel of 0.2% would work fine.  If instead, you wished to use AZCL-Beta-Glucan in agar plates, simply suspend the AZCL-Beta-Glucan in the agar solution before pouring (this substrate does not dissolve; it hydrates to give gel particles).

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