ANTI BIOFILM ACTIVITY OF TRITERPENOIDS: AN OVERVIEW

Abstract

Phytochemicals, bioactive chemicals of plant origin, have long been used as herbal medicines in many countries but have become increasingly receptive in modern day biology for their non toxicity and easy availability. Among all the available groups, (like polyphenols, flavonoids, alkaloids) pentacyclictriterpenoids have received much attention for their wide range of therapeutic properties including anti-inflammatory, anti-cancer, anti-oxidant, anti-viral effects. They are further classified into three groups namely oleanane, ursane and lupane and Glycyrrhetinicacid (GA), ursolic acid (UA), and betulinic acid(BA) are three representative examples from each group respectively. All three compounds have been widely studied for establishing their anti-inflammatory, anti-cancer, anti-tumor and anti-microbial roles among many others. GA, UA and BA have also been studied for their anti-biofilm action. Anti-biofilm activity of various degrees have been established for all the triterpenoids against bacteria, particularly Streptococcus mutans, Staphylococcus aureus and other Gram positive pathogens and more recently against Pseudomoans aeruginosa. Though the precise mechanism of intervention remains elusive. Quorum sensing (QS) mediated alteration of gene expression has been associated with biofilm formation. In a systemic exploration for profiling action of petnacyclictriterpenoids against biofilms formed by Gram negative bacteria, GRA, UA and BA have been implicated in biofilm formation inhibition through impairing QS in Vibrio choleare, Pseudomoans aeruginsoa and Acinetobacter baumannii by interacting with various effectors of acylatedhomoserine lactone (AHL) based and autoinducer (AI) based QS-cascades. Within the scope of this review a brief retrospective of pentacyclictriterpenoid as candidate anti-biofilm agent is provided. Alongside, possible therapeutic applicability as a novel scaffold for drug development or in combination with antibiotics is also discussed.