Could Mulberry Extract be the Key for Diabetes?

Writing in the Journal of Agricultural and Food Chemistry, the researchers describe the production of a food-grade mulberry powder with an optimised content of 1- deoxynojirimycin (DNJ) content, a compound shown to inhibit the action of the glucosidase enzyme that controls the digestion of carbohydrates. 'This study suggests that the newly developed DNJ-enriched powder can be used as a dietary supplement for preventing diabetes mellitus,' wrote lead author Toshiyuki Kimura from Tohoku University. An estimated 19 million people are affected by diabetes in the EU, equal to four per cent of the total population. This figure is projected to increase to 26 million by 2030. While DNJ has been shown to inhibit glucosidase, the concentration of the compound in commercial mulberry products is extremely low, state the researchers, with levels as low as about 0.1 per cent. Kimura and co-workers set about producing a food-grade mulberry powder with high DNJ content. Through clinical trials they then determined the optimal dose of the powder needed to suppress blood glucose levels after a meal. The researchers eventually obtained a mulberry powder containing 1.5 per cent DNJ. 'Young mulberry leaves taken from the top part of the branches in summer contained the highest amount of DNJ,' wrote the authors. To test the efficacy of the extract, the researchers recruited health volunteers and assigned them to receive varying levels of DNJ-enriched powder. This was followed by 50 g of sucrose. Blood glucose and insulin levels were measured before sucrose consumption, and again 30-180 minutes later. The researchers found that a suitable dose of DNJ reduced the levels of glucose and insulin in the blood after a meal, suggesting that it could be an effective prevention measure for those at risk from diabetes. DNJ is not yet available for general use.