Isolation, characterization and biological properties of betulin from Entada africana Guill. and Perr. (Mimosaceae).

Abstract

The present study is aimed at the isolation, characterization and evaluation of some biological properties of betulin from Entada africana stem bark extract. A dichloromethane soluble portion of the stem bark methanol/acetone (1:1 v/v) extract was subjected to gradient elution using ethyl acetate in hexane (5 -30 %) on an open column. A pure compound was obtained with Rf = 0.61 in hexane/ethyl acetate (8:2 v/v) after repeated washing and recrystallization from methanol and coded Enac1. The pure compound was analyzed using IR, 1 H & 13 C NMR and GC-MS. Clinical isolates of Escherichia coli, Klebsiella pneumoniae, Salmonella typhi and Staphylococcus aureus were used to assess the antibacterial activity of the pure compound while its preliminary Cytotoxicity was evaluated using brine shrimp nauplii. Based on the spectroscopic data obtained and in comparison with literature, the isolated compound was identified as betulin. The minimum inhibitory concentration (MIC) of betulin ranged between 62.50 -250.00 µg/mL for all the four bacterial isolates in the study while its fifty percent lethal concentration (LC50) was 10.00 µg/mL. Significant Cytotoxicity with moderate antibacterial activity was observed. The study therefore justifies the existence of bioactive compounds in the stem bark of Entada africana and its use in traditional medicine.

Isolation and characterization of Stigmasta-7, 22-dien-3-ol (α-Spinasterol) from Entada africana stem bark crude extract

“…Despite the medicinal potentials of Entada africana, there exist only few studies on the isolation and characterization of its phytoconstituents. These studies include the isolation of acidic wound healing polysaccharides (Diallo et al, 2001), myricetin and derivatives (Montoro et al, 2005), antiproliferative triterpene saponins (Cioffi et al, 2006) and betulin (Kwaji et al, 2018) based on available literature. In furtherance of our effort to make more information available on the chemical constituents of Entada africana, we report the isolation and characterization ofStigmasta-7, 22-dien-3-ol from Entada africana stem bark crude extract for the first time.…”

Development and Validation of an GC-MS Method to Quantify Phytoconstituents by Using Entada pursaetha DC

“…Whereas in allied species of E. africana is also noted the same compound but due to geographical isolation and topotype of the species may varied the percentage of proportions of active constituents (Dong et al, 2012;Singh et al, 2011). Various parts of the E. africana was reported different chemicals such as polysaccharides (Diallo et al, 2001), betulin (Kwaji et al, 2018), saponins (Yusuf et al, 2019) and glycosides (Kwajiet al, 2017). However, in E. pursaetha needs further study for extraction, isolation and characterization of tagged phytomolecules with specific geographical chemotype.…”

The phytochemical and pharmacological actions of Entada africana Guill. & Perr.

“…Ea have been reported to contain high percentage of triterpenes; Betulin (1) was isolated from the dichloromethane soluble portion of the stem bark of the plant (Kwaji et al., 2018). Nine new triterpenes saponins (2–3) were isolated form the roots of E. africana (Cioffi et al., 2006).…”

“…Antibacterial activity of Betulin (1) from the dichloromethane soluble portion of the mmethanol/acetone (1:1 v/v) stem bark extract of Ea was conducted against E. coli , K. pneumonia , S. typhi and S. aureus ; the study revealed an MIC range between 62.50 – 250 μg/mL for betulin (Kwaji et al., 2018).…”

“…Cytotoxicity studies of Betulin form the stem bark of Ea evaluated using brine shrimp nauplii revealed an LC 50 value of 10.00 μg/mL indicating significant cytotoxic effect (Kwaji et al., 2018).…”