Soxhlet extractor coupled with Liquid-liquid extraction: Setting up a pilot library of refined crude extracts from indigenous medicinal plants of Lesotho

Abstract

Infections associated with multidrug resistant organisms result in increased morbidity and mortality in Lesotho and globally, thus, there is immediate need to discover new antibiotics against resistant bacteria through systematic examination of inexpensive local herbs. Here, we report for the first time, the well-defined and publicly available prototype library that consists of 20 different crude extracts derived from crude drug samples of medicinal plants of Lesotho used for treatment of infectious diseases. We also described the coupling of soxhlet extraction with liquid-liquid fractionation to give partially refined organic and aqueous extracts, and disclose that the extracts from the leaves and whole plant contained about twice as much organic soluble phytochemicals as aqueous soluble phytoconstituents. While the roots and bark contained about 2 and 5 times more of aqueous soluble than organic soluble phytochemicals respectively, especially when extracting with 90% ethanol. The library represents the potential phytochemicals in herbal prescriptions dispensed by traditional healers in Lesotho. The extracts are publicly available upon request through the corresponding author and efforts to expand the library are still continuing. This methodology could be followed to develop other libraries.