Antimicrobial Activity of Oleanolic and Ursolic Acids: An Update

Abstract

Triterpenoids are the most representative group of phytochemicals, as they comprise more than 20,000 recognized molecules. These compounds are biosynthesized in plants via squalene cyclization, a C30 hydrocarbon that is considered to be the precursor of all steroids. Due to their low hydrophilicity, triterpenes were considered to be inactive for a long period of time; however, evidence regarding their wide range of pharmacological activities is emerging, and elegant studies have highlighted these activities. Several triterpenic skeletons have been described, including some that have presented with pentacyclic features, such as oleanolic and ursolic acids. These compounds have displayed incontestable biological activity, such as antibacterial, antiviral, and antiprotozoal effects, which were not included in a single review until now. Thus, the present review investigates the potential use of these triterpenes against human pathogens, including their mechanisms of action, via in vivo studies, and the future perspectives about the use of compounds for human or even animal health are also discussed.

In vitro effectiveness of triterpenoids and their synergistic effect with antibiotics against Staphylococcus aureus strains

“…Oleanolic acid and ursolic acid take up a variety of different mechanisms to exert their effects. They could inhibit peptidoglycan synthesis and thus affect cell wall, or they can induce stress conditions in bacteria,[19] but their mechanism in S. aureus is not properly understood. [6] The MIC of these triterpenoids was greater in MRSA than MSSA [Table 1], and this finding correlates with other researchers as well.…”

In Vitro Evaluation of the Antimicrobial Ability and Cytotoxicity on Two Melanoma Cell Lines of a Benzylamide Derivative of Maslinic Acid

“…Phytochemicals such as oleanolic and ursolic acid belonging to the same group of pentacyclic triterpenes have been previously reported to exert antibacterial, antiviral, and antiprotozoal effects [25]. Chouaïb et al evaluated the antimicrobial activity of maslinic and oleanolic acid esters and noted that compounds containing extra sulfur and chlorine substituents were active against S. aureus, E. faecalis, E. coli , and P. aeruginosa [12].…”

Antimicrobial activity of extracts from olive and basil leaves against pathogenic microbial isolates from outpatient clinics of the Research Institute of Ophthalmology

“…Amino acid sequencing of resistant and sensitive Candida tropicalis strains. Jesus et al [31] reported that triterpenoids are the most representative group of phytochemicals, but due to their low hydrophilicity, triterpenes were considered to be inactive for a long period of time; however, evidence on their wide range of pharmacological activities is emerging, and elegant studies have highlighted these activities. Several triterpenic skeletons have been described, including some that have presented with pentacyclic features, such as oleanolic and ursolic acids.…”