Natural antibiofilm agents and the need for antibiofilm drug leads

Plant with medicinal property contains different types of bioactive compounds and these compounds are effective against certain diseases. Biofilm infection is a disease caused by biofilm which is associated with the respiratory and gastrointestinal infections. Biofilm-producing bacteria as such Pseudomonas aeruginosa strain PA14 is a serious treat in hospitals. The bacterium possesses many virulent factors that contributed to its pathogenesis and resistance thus caused the inhibition and removal of its biofilms a difficult task. This study therefore attempts to identify natural antibiofilm agents against the P. aeruginosa PA14 biofilms. The activity of plant extracts and subsequently purified compounds was evaluated using a stepwise separation process called bioassay-guided fractionation. The fractionation process involved the use of chromatographic techniques and compounds were identified using NMR, GC-MS and LC-MS. A total of four bioactive fractions namely (E333F1S1), (E341), (HA6) and (M338B) have been discovered with antibiofilm activity and were selected for further investigation. The active fraction from Ribes nigrum leaf (E333F1S1) contained mixtures of alkanes while active extract of Sambucus nigra flower (E341) contained a mixture of ursolic acid and oleanolic acid. The LC-MS analysis on Coriandrum sativum seeds (HA6) revealed the presence mixture of oxygenated monoterpenes, while another active fraction of C. sativum seeds (M338B) showed the presence of carboxylic acid, carboxylate, tetraone, glycerol, carbohydrate and fatty acids. Thus, the discovery of potential bioactive compounds from this study could be further investigated as antibiofilm drug leads to battle the infections by P. aeruginosa PA14 biofilm in the near future.