Antimicrobial Activity and Chemical Composition of Callistemon Pinifolius and C. Salignus Leaf Essential Oils from the Northern Plains of India

Abstract

Biological and chemical investigations were carried out to evaluate the antimicrobial potential of Callistemon pinifolius and C. salignus leaf oils for herbal medicines. Disk diffusion and micro broth dilution methods were used for the evaluation of the antimicrobial activity of the essential oils against selected strains of bacteria (Staphylococcus aureus, S. epidermidis, Streptococcus mutans, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter aerogenes and Escherichia coli) and fungi (Candida albicans, Cryptococcus neoformans, Trichophyton rubrum, Aspergillus flavus, A. niger, and Sporothrix schenckii ). Analysis of the leaf essential oil of C. pinifolius and C. salignus using GC and GC-MS resulted in the identification of fifty five and fifty one compounds, respectively. 1,8-Cineole (39.1% and 40.8%), α-pinene (26.7% and 24.2%), and (E)-β-terpineol (9.6% and 13.5%), were the major constituents. The isolated essential oils could be of use for the future development of antimicrobial agents.

Volatile organic compounds emitted by bottlebrush species affect the behaviour of the sweet potato whitefly

“…The leaf volatile profiles identified by SPME-GC mass spectrometry showed that C. pallidus was the only species among the three tested that contained a considerable percentage of linalool in the headspace, while C. laevis and C. phoeniceus headspaces were characterized by higher percentages of 1,8-cineole, the main oxygenated monoterpene. This result is in good agreement with previous studies on other species of this genus, where 1,8-cineole was found to vary between 30 and 90 % (Abdelhady and Aly 2012, Oyedeji et al 2009, Saxena et al 2008, Sharma et al 2006 2013). Behavioural bioassays carried out in the Y-tube olfactometer with pure compounds showed that the whitefly adults were more attracted to linalool compared with pure air, while 1,8-cineole was not an attractant and, to a certain extent, it was repellent.…”