Medicinal Plants Classification Biosynthesis and ... - Index of

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Vandana Gulati, Ian H. Harding and Enzo A. Palombo
that there is increased risk of developing Type II diabetes from lack of exercise and sedentary
lifestyle (16).
Many studies have confirmed the benefits of medicinal plants with hypoglycemic effects
in the management of diabetes mellitus. The effects of these plants may delay the
development of diabetic complications and correct metabolic abnormalities. Moreover,
during the past few years, some of the new bioactive drugs isolated from plants showed
antidiabetic activity with more efficacy than oral hypoglycemic agents used in clinical
therapy (17).
The folk medicines used for the treatment and prevention of diabetes include garlic,
onion, ginseng, bitter melon, fenugreek, Gymnema sylvestre, Pterocarpus marsupium and
other plants containing flavonoid compounds, bilberry, aloe vera, and holly. The active
ingredients derived from plants used for antidiabetic preparations have been identified, and
potentially beneficial effects on the rate of food ingestion, glucose transport, potentiation of
insulin release, inhibition of insulin clearance, insulin-mimetic effects, reduced
gluconeogenesis, and β-cell protection have been attributed to these agents (18). Some plants,
such as G. sylvestre, M. charantia and P. marsupium, may also help in regeneration of β cells
in the pancreas, which is an important discovery because none of the conventional oral
hypoglycemic agents shows this action (5).
Dietary management of diabetes includes consumption of food, spices, fruits, vegetables,
traditional medicines and herbs. The diet should provide adequate amounts of vitamins,
minerals, carbohydrates, fats and proteins. Diets which enhance glycemic control are high in
fibre, low to moderate in fats and moderate in biological value proteins like legumes, beans,
vegetables, soy and other plant based proteins which our body can digest, absorb and utilize
easily. The decrease of calorie intake in diabetic patients helps in weight loss. Diets rich in
fibre and containing 60% carbohydrates improve blood sugar and lipid levels. Thus, dietary
modification is the first line of therapy for diabetic patients. Dietary strategies normalize
blood glucose and lipoprotein levels to reduce morbidity and mortality caused by disturbance
in carbohydrates and lipoprotein metabolism in diabetes mellitus. These goals can be
achieved by considering the quantity and quality of diets according to the clinical conditions
of an individual (19).
Some examples of dietary management of diabetes which have been evaluated
scientifically are described below.
A considerable number of human and animal experiments have been carried out to
evaluate the efficacy of common spices and natural food adjuncts for several physiological
effects such as antidiabetic, digestive stimulant, cholesterol lowering, anti-carcinogenic, antiinflammatory,
anti-oxidant and anti-lithogenic potential. Several common spices such as
fenugreek (Trigonella foenumgraecum) were studied on diabetic and normal rats, mice,
rabbits and dogs which was also confirmed by human clinical trials that fenugreek possess
beneficial hypoglycemic potential. Garlic (Allium sativum), onion (Allium cepa), cumin
(Cuminum cyminum), turmeric (Curcuma longa) are some other spices with beneficial antidiabetic
properties (based on animal studies). Experimental data indicated that dosages of 25-
50 grams of fenugreek seeds, 5-6 garlic cloves, 1 onion bulb, and 1 gram of turmeric powder
incorporated into the daily diet of diabetics were effective as a support therapy in the
prevention and management of diabetes and related complications like hypertension and