In Vitro Propagation and Biotechnological Improvement Strategies of Plants with High-Intensity Sweetener and Anti-Diabetic Activities

Diabetes mellitus is an endocrine and metabolic disease with high prevalence worldwide. Moreover, sugar intake has increased in the last decades leading to a higher risk of obesity and type 2 diabetes. Therefore, new compounds have been prospected for the food industry to produce very low-calorie and intense sweeteners from natural sources. Besides, medicinal plants with anti-diabetic activities have become popular as an alternative to drug treatments. This study aimed to perform a systematic review of plants that combine these two properties: sweeteners and anti-diabetic activity. Four plant species were identified following these features, one widely known as a sweetener (Stevia rebaudiana Bertoni) and three less common high-potency sweeteners (Cyclocarya paliurus (Batal.) Iljinsk, Glycyrrhiza glabra L., and Siraitia grosvenorii (Swingle) C. Jeffrey ex A. M. Lu and Zhi Y. Zhang). First, the bioactive compounds and the pathways involved in their biosynthesis are summarized. Afterwards, we describe the anti-diabetic action and other medicinal effects of these species. Moreover, we reviewed the principal in vitro propagation studies and biotechnological strategies reported so far on these species. Finally, the most promising biotechnological approaches and future perspectives for the industrial exploitation of these species are discussed.