Background:
Diabetes is a chronic disease affecting a large population worldwide and stands as one of the
major global health challenges to be tackled. According to World Health Organization, about 400 million are having
diabetes worldwide and it is the seventh leading cause of deaths in 2016. Plant based natural products had been in use
from ancient time as ethnomedicine for the treatment of several diseases including diabetes. As a result of that, there are
several reports on plant based natural products displaying antidiabetic activity. In the current review, such antidiabetic
potential compounds reported from all plant sources along with their chemical structures are collected, presented and
discussed. This kind of reports are essential to pool the available information to one source followed by statistical analysis
and screening to check the efficacy of all known compounds in a comparative sense. This kind of analysis can give rise to
few numbers of potential compounds from hundreds, whom can further be screened through in vitro and in vivo studies,
and human trails leading to the drug development.
Methods:
Phytochemicals along with their potential antidiabetic property were classified according to their basic chemical
skeleton. The chemical structures of all the compounds with antidiabetic activities were elucidated in the present review.
In addition to this, the distribution and their other remarkable pharmacological activities of each species is also included.
Results:
The scrutiny of literature led to identification of 44 plants with antidiabetic compounds (70) and other
pharmacological activities. For the sake of information, the distribution of each species in the world is given. Many plant
derivatives may exert antidiabetic properties by improving or mimicking the insulin production or action. Different
classes of compounds including sulfur compounds (1-4), alkaloids (5-11), phenolic compounds (12-17), tannins (18-23),
phenylpropanoids (24-27), xanthanoids (28-31), amino acid (32), stilbenoid (33), benzofuran (34), coumarin (35),
flavonoids (36-49) and terpenoids (50-70) were found to be active potential compounds for antidiabetic activity. Of the 70
listed compounds, majorly 17 compounds are from triterpenoids, 13 flavonoids and 7 are from alkaloids. Among all the 44 plant species, maximum number (7) of compounds are reported from Lagerstroemia speciosa followed by Momordica
charantia (6) and S. oblonga with 5 compounds.
Conclusion:
This is the first paper to summarize the established chemical structures of phytochemicals that have been
successfully screened for antidiabetic potential and their mechanisms of inhibition. The reported compounds could be
considered as potential lead molecules for the treatment of type-2 diabetes. Further, molecular and clinical trials are
required to select and establish the therapeutic drug candidates.