ISSN : 2708-7743 (print), eISSN : 2708-5422

Effects of gibberellic acid on the synthesis of alpha and beta-amylase during sorghum malting (Sorghum bicolor L. (Moench)


Description of the subject. The use of red sorghum in brewing offers several benefits including the absence of gluten. But it is problematic because it contains huge amounts of polyphenols and has low alpha and beta-amylase activations compared to barley, hence the need to improve them.
Objectives. The overall goal is to contribute to the utilization of red sorghum in modern brewing. Specifically, the study aims to evaluate the effect of added gibberellic acid on the synthesis of alpha and beta-amylase during red sorghum and corn malting.
Methods. To improve alpha and beta-amylase activities, the effects of a treatment factor with 3 modalities (CORN: corn; NDRS: non-discolored sorghum and DRS: discolored sorghum) in 4 soaking solutions (distilled water, distilled water +500 ppm gibberellic acid (GA), distilled water + 500 ppm acetone/water extract (70/30: V/V), distilled water + 500 ppm, GA + 500 ppm acetone/ water extract (70/30: V/V), a gibberellic acid content factor and an acetone / water extract factor (70/30: V/V) were studied.
Results. The results showed that GA has a significant effect on α-amylase synthesis during DRS malnutrition whereas no evidence is given in this study neither on the reasons for this lack of response during α-amylase malnutrition NDRS, nor on the lack of effect of GA addition on beta-amylase synthesis.
Conclusion. This study showed that increasing the acetone/water extract content (70/30: V/V) decreases the synthesis of both alpha-amylase and beta-amylase activity during of discolored red sorghum malting (DRS).

Keywords : Red sorghum, alpha and beta-amylase, phenolic compounds, gibberellic acid.

Arthur Amisi Kapepa, Déogracias Mava, Robby Kasonga Tshilewu, Richard Makaba Ma Eloko, Jean-Claude Bwanganga Tawaba