Antimycobacterial, docking and molecular dynamic studies of pentacyclic triterpenes from Buddleja saligna leaves

Buddleja saligna (family Buddlejaceae) is a medicinal plant endemic to South Africa. Two isomeric pentacyclic triterpenes, oleanolic acid and ursolic acid, were isolated from the leaves of B. saligna using silica gel column chromatography. Compounds oleanolic acid and ursolic acid were subjected to derivatization with acetic anhydride in the presence of pyridine to obtain oleanolic acid-3-acetate and ursolic acid-3-acetate, respectively. The structures of these compounds were fully characterized by detailed nuclear magnetic resonance (NMR) investigations, which included 1H and 13C NMR. Molecular docking studies predicted the free binding energy of the four triterpenes inside the steroid binding pocket of Mycobacterium tuberculosis fadA5 thiolase compared to a reported inhibitor. Thus, their ability to inhibit the growth of M. tuberculosis was predicted and was confirmed to possess significant antimycobacterial activity when tested against Mycobacterium smegmatis, M. tuberculosis H37Rv (ATCC 25177), clinical isolates of multi-drug-resistant M. tuberculosis (MDR-TB) and extensively drug-resistant M. tuberculosis (XDR-TB) using the Micro Alamar Blue Assay. Ursolic acid was isolated from this plant for the first time.

Grantor dc:publisher

Taylor and Fancis Online

Year dc:date

2017

Authors dc:creator

• Singh, Alveera
• Venugopala, Katharigatta Narayanaswamy
• Khedr, Mohammed A.
• Pillay, Mellendran
• Nwaeze, Kenneth U.
• Coovadia, Yacoob
• Shode, Francis
• Odhav, Bharti

• Antimycobacterial activity
• Buddleja saligna
• Docking
• fadA5 thiolase
• Oleanolic acid
• Pentacyclic triterpenes
• Ursolic acid

Language dc:language

en

Identifier

Singh, A. 2017. Antimycobacterial, docking and molecular dynamic studies of pentacyclic triterpenes from Buddleja saligna leaves. Journal of Biomolecular Structure & Dynamic. 35(12): 2654-2664.
0739-1102 (print)
1538-0254 (online)

OAI identifier oai:identifier

oai:openscholar.dut.ac.za:10321/2582