Micropropagation and medicinal properties of Barleria greenii

ABSTRACT
The crisis of newly emerging diseases and the resistance of many pathogens to
currently used drugs, coupled with the adverse side-effects of many of these drugs
have necessitated the continuous search for new drugs that are potent and
efficacious with minimal or no adverse side-effects. The plant kingdom is known to
contain many novel biologically active compounds, many of which could potentially
have a higher medicinal value when compared to some of the current medications.
Indeed, the use of plants in traditional medicine, especially in African communities,
is gaining more importance due to their affordability and accessibility as well as
their effectiveness. Exponential population growth rates in many developing
countries has resulted in heavy exploitation of our plant resources for their
medicinal values. In addition, plant habitat destruction arising from human
developmental activities has contributed to the fragmentation or loss of many plant
populations. Owing to these factors, many plant species with horticultural and/or
medicinal potential have become either extinct or are threatened with extinction.
These threatened species cut across different taxonomic categories including
shrubs, trees and succulents. Without the application of effective conservation
strategies, the medicinal and/or horticultural potential of such threatened species
may be totally lost with time. The extinction of such species could lead to the loss
of potential therapeutic compounds and/or genes capable of being exploited in the
biosynthesis of new potent pharmaceutical compounds.
The overall aims of this study were to establish efficient regeneration protocols
and explore the medicinal properties of two threatened South African species
belonging to different taxonomic categories: Barleria greenii (a shrub) and Huernia
hystrix (a succulent). Barleria greenii is a perennial ornamental and a critically
endangered shrub, endemic to a small area in KwaZulu-Natal province of South
Africa. Its conventional propagation is hampered by high seed parasitism and
difficulty in rooting. Huernia hystrix is a dwarf perennial stem succulent heavily
exploited for traditional medicine among the Zulu people in South Africa. It is
considered vulnerable in KwaZulu-Natal province, an endangered endemic to the
flora of the southern Africa region and is vulnerable in its global conservation
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