GC-MS Analysis of Frankincense Extracts which Inhibit the Growth of Bacterial Triggers of Selected Autoimmune Diseases

Abstract

Introduction: Frankincense has been used traditionally for the inhibition of microbial growth and for the treatment of rheumatic diseases. Despite this, frankincense extracts are yet to be tested for the ability to inhibit the growth of the bacterial triggers of autoimmune inflammatory diseases. Methods: Solvent extracts prepared from commercially obtained frankincense were analysed for the ability to inhibit the growth of bacterial species associated with initiating rheumatoid arthritis (P. mirabilis), ankylosing spondylitis (K. pneumoniae) and multiple sclerosis (A. baylyi, P. aeruginosa) by disc diffusion assay, and quantified by MIC determination. Toxicity was determined by Artemia franciscana bioassay.The most potent inhibitory extracts were investigated using non-targeted GC-MS head space analysis (with screening against a compound database) for the identification and characterisation of individual components in the crude plant extracts. Results: Methanolic and aqueous frankincense extracts inhibited the growth of all bacterial species. The growth inhibition of these extracts was particularly notable against P. mirabilis and K. pneumoniae, with MIC values generally ≤ 1000 µg/mL for both reference and clinical bacterial strains. Indeed, the MIC values of the methanolic extract against P. mirabilis, and for the aqueous extract against K. pneumonia, were as low as 59.6 and 75.2 µg/mL respectively. The methanolic and aqueous extracts also inhibited the growth of A. baylyi and P. aeruginosa. However, with the exception of the growth inhibition of A. baylyi by the aqueous extract (MIC=4313 µg/mL: moderate inhibitory activity), the MICs against these bacteria was indicative of only low inhibitory activity. The ethyl acetate, chloroform and hexane extracts also inhibited the growth of all bacterial species, albeit with low efficacy (MIC values generally >5000 µg/mL against all bacterial species). All frankincense extracts were non-toxic in the Artemia franciscana bioassay, with LC 50 values substantially above 1000 µg/mL. Non-biased GC-MS headspace analysis of the methanolic and aqueous extracts putatively identified a high diversity of monoterpenoids and sesquiteriterpenoids. Conclusion: The lack of toxicity and the inhibitory activity of the methanolic and aqueous frankincense extracts against microbial triggers of rheumatoid arthritis and ankylosing spondylitis indicates their potential in the treatment and prevention of these diseases.

Cakile maritima Scop. extracts inhibit the growth of some bacterial triggers of autoimmune diseases: GC-MS analysis of an inhibitory extract

“…Indeed, previous studies from our group have also shown the low susceptibility of these P. aeruginosa strains to conventional antibiotics. 35,36 The methanolic and ethyl acetate extracts also inhibited P. aeruginosa growth, albeit with substantially smaller zones of inhibition (6.0 ± 0 and 6.7 ± 0.3 mm, respectively). The antimicrobial efficacy was further quantified by determining the MIC values for each extract against the microbial species which were determined to be susceptible.…”

“…35,36 The system was equipped with a Shimadzu auto-sampler AOC-5000 plus (USA) fitted with a solid phase micro-extraction fibre (SPME) handling system utilising a Supelco (USA) divinely benzene/carbowax/polydimethylsiloxane (DVB/CAR/ PDMS). Chromatographic separation was accomplished using a 5% phenyl, 95% dimethylpolysiloxane (30 m×0.25 mm id×0.25 um) capillary column (Restek USA).…”

An examination of the Antimicrobial and Anticancer Properties of Khaya senegalensis (Desr.) A. Juss. Bark Extracts

“…This finding is supported by previous studies which have also reported these strains to be antibiotic resistant. 24,47 Thus, the K. senegalensis extracts are particularly potent growth inhibitors and may be useful for the inhibition of P. aeruginosa growth. Therefore, as both A. baylyi and P. aeruginosa can trigger multiple sclerosis in genetically susceptible individuals, 44 these extracts have potential in the prevention and treatment of this disease.…”

An upscaled extraction protocol for Tasmannia lanceolata (Poir.) A.C. Sm.: Anti-bacterial, anti-Giardial and anticancer activity

“…27 Briefly, the system was equipped with a Shimadzu auto-sampler AOC-5000 plus (USA) fitted with a solid phase micro-extraction fibre (SPME) handling system utilising a Supelco (USA) divinyl benzene/ carbowax/polydimethylsiloxane (DVB/CAR/PDMS). Chromatographic separation was accomplished using a 5% pheny l, 95% dimethylpolysiloxane (30 m×0.25 mm id×0.25 µm) capillary column (Restek USA).…”

“…This finding is supported by previous studies which have also reported these strains to be antibiotic resistant. 23,27 Thus, despite the relatively small inhibition zones, the T. lanceolata extracts may still be useful for the inhibition of P. aeruginosa growth. Therefore, as both A. baylyi and P. aeruginosa can trigger multiple sclerosis in genetically susceptible individuals, 28,29 these extracts have potential in the prevention and treatment of this disease.…”