Tools from biodiversity: Wild nutraceutical plants

Abstract

Food security and medicine have always been challenging issues. Strategic efforts from 1989 include DeFelic’s term “Nutraceutical” combining “Nutrition” and “Pharmaceutical” uses. Several species of the genus Dioscorea, abundant in Similipal Biosphere Reserve forest, Odisha, India, are locally used as medicine for abdominal pain, birth control, diarrhoea, labour pain (during delivery), abdominal worm, as antidotes for scorpion bite, and in treatment of skin infections. Tubers of Dioscorea species have high proportions of carbohydrate, starch and fibre. Starchy components (nutritional) make them optional food during critical periods of drought and famine among the tribal communities of the region, whereas “anti-nutritional” components give a bitter taste. Anti-nutritional factors may be neutralized using molecular technique. These plants have bioactive compounds including steroids saponin and diosgenin. Recently, a series of pre-clinical and mechanistic studies have been independently conducted to understand beneficial roles of diosgenin against metabolic diseases (hypercholesterolemia, dyslipidemia, diabetes, and obesity), inflammation, and cancer. Diosgenin is also used in commercial synthesis of Cortisone, Progesterone, and other similar products. In experimental models of obesity, diosgenin decreases plasma and hepatic triglycerides and improves glucose homeostasis, by promoting adipocyte differentiation and inhibition of inflammation in adipose tissues. Expression studies are required to ascertain regulatory modulation of genes and to silence bitterness producing genes. Potentially, Dioscerea are new horticultural crop in the farm, of both nutritional and pharmaceutical value, and for increased synthesis of diosgenin and other active secondary metabolites, formulating new drugs as well. Genes involved in biochemical synthesis and pathways are cooperatively expressed to ensure function. Information on co-expression/regulation is the key in understanding biological value at the molecular level. Quantitative genetic/mathematic studies help to dissect the pathway.