Chemical Composition and Antimicrobial Activity of the Essential Oil of Pimpinella puberula (DC.) Boiss

In this study, the aerial parts of Pimpinella puberula were collected from Ramhormoz and Mashhad (Khuzestan and Khorasan Provinces) at the vegetative, flowering and seeding stages. Essential oils from the whole aerial parts as well as stem/leaf, inflorescence, unripe and ripe seeds, were isolated by hydro-distillation. The yields of essential oil obtained from the Ramhormoz samples were 0.49%, 0.31%, 3.81%, 6.01% and 1.80% w/w, and from those from Mashhad were 0.96%, 0.87%, 3.59%, 6.94% and 4.96% w/w, respectively. The oils from different parts of plant were also analyzed by GC and GC/MS. Limonene was the major constituent in all the oils (21.7%-82.4%), followed by pregeijerene (14.6%-55.4%) and geijerene (7.2%- 11.7%). Methyl eugenol and elemicine, however were only found in the Ramhormoz oil samples. The antimicrobial activity of the oils was determined using the disk diffusion method against Gram positive bacteria (Bacillus subtilis, Bacillus cereus, Micrococcus luteus and Staphylococcus aureus), Gram negative bacteria (Yersinia entrocolitica, Klebsiella oxytoca, Serratia marcescens, Escherichia coli and Pseudomonas aeruginosa) and yeast (Candida albicans). Results showed a significant difference between Gram positive and Gram negative bacteria in their susceptibility to the oil, although Gram positive bacteria were more susceptible to the antimicrobial activity of P. puberula oil. In addition, the antimicrobial activity of samples collected from Ramhormoz were more than of those from Mashhad