Antibacterial activity of oleanolic and ursolic acids and their derivatives

Abstract

Bacterial resistance to antibiotics is increasing at an alarming rate and many commonly used antibiotics are no longer effective.Thus, there is considerable interest in investigating novel antibacterial compounds, such as the plant-derived pentacyclic triterpenoids, including oleanolic acid (OA), ursolic acid (UA) and their derivatives. These compounds can be isolated from many medicinal and crop plants and their antibacterial, antiviral, antiulcer and anti-inflammatory effects are well documented. OA and UA are active against many bacterial species, particularly Gram-positive species, including mycobacteria. They inhibit bacterial growth and survival, and the spectrum of minimal inhibitory concentration (MIC) values is very broad. In addition, OA, UA and their derivatives display potent antimutagenic activity. Studies to identify the cellular targets and molecular mechanisms of OA and UA action were initiated a few years ago and it has already been demonstrated that both acids influence bacterial gene expression, the formation and maintenance of biofilms, cell autolysis and peptidoglycan turnover. Before these compounds can be used clinically as antimicrobial agents, further extensive studies are required to determine their cytotoxicity and the optimum mode of their application.

Application of Response Surface Methodology for Optimisation of Simultaneous UHPLC-PDA Determination of Oleanolic and Ursolic Acids and Standardisation of Ericaceae Medicinal Plants

“…All analytes were found stable in neutral solutions, with the 30th-day recovery >96%. 3 Separation time (retention time of the last peak). 4 Limit of detection.…”

“…As the underlying mechanism of this action, the suppression of immune cells and cytokines (TNF-α, IL-12, IL-6, interferon-γ) production either via inhibition of pro-inflammatory enzymes (elastase, cyclooxygenases, lipoxygenases, nitric oxide synthase) and NF-κB-regulated genes expression or direct cytokine receptor interactions has been proposed [1,2]. Recently, the potent antimicrobial activity of both compounds has also been demonstrated towards various bacterial strains including Escherichia coli-a common pathogen of urinary tract infection [3]. OA and UA were found to modulate bacterial resistance to some antibiotics and produce in Ericaceae is a large family of flowering plants comprising over 4000 species of great morphological and ecological diversity, and with almost worldwide distribution [7].…”

Anti-infective Properties of Brachychiton rupestris and Brachychiton luridum Leaves and their Qualitative Phytochemical Screening

“…Meanwhile, the effect of B. luridum dichloromethane fraction of the leaves against Gram-negative bacteria such as Escherichia coli was suggested to be due to triterpenes which were reported before such as β-amyrin, β-amyrin acetate, lupeol and oleanolic acid [11]. Oleanolic acid, for example, was reported to exhibit antibacterial activity against Gram-negative bacteria by alteration of bacterial shape and inhibition of bacterial growth and survival [50]. Lupeol was reported in another study to exhibit antibacterial activity against Escherichia coli [51].…”

Antibacterial Effect of Pulsatilla chinensis towards Staphylococcus aureus, Shigella dysenteriae, and Salmonella typhi

“…These chemical substances have antibacterial properties and have been proved in the previous studies. [3][4][5][6][7][8] If Pulsatilla chinensis proved to have antibacterial effect on pathogenic intestinal bacteria, it is not just provide a new alternative treatment for diarrhea and dysentery, but also for other intestinal infectious diseases. This study aimed to determine the antibacterial effect of P. chinensis towards staphlococcus aureus, Shigella dysenteriae, and Salmonella typhi.…”