Purification partielle et caractérisation de la dextrinase limite du malt de sorgho Safrari

Limit dextrinase from Safrari sorghum malt was purified by maximizing its ammonium sulfate precipitation followed by dialysis. This purification led to a partially purified extract whose yield was 75% for a purification factor of 6.5. The characteristics of the purified limit dextrinase are as follows: optimum pH for activity and stability of 5.0-5.5; optimum temperature for activity and stability of 50 – 60°C. The kinetic parameters were 0.03 mg.mL-1.sec-1 and 2.4 mg.mL-1 for Vmax and KM respectively. Limit dextrinase is a sulfhydryl enzyme and its activity is enhanced in the presence of ascorbic acid; but also, in the presence of bovine serum albumin or calcium chloride. The filtration of sorghum mash is improved in the presence of purified exogenous limit dextrinase. Practical Applications : It is possible to lower the turbidity of worts by using limit dextrinase, which is derived from the Cameroonian sorghum variety Safrari. This is especially helpful when brewing with cereals, which results in beers that are cloudy. This is quite significant because none of the enzymes utilized in the brewing facilities in Cameroon are sourced from the country's own natural resources.