Investigation of effects of Gaharu distillates on lung cancer cells

Abstract

Agarwood or Gaharu is the fragrant, resinous heartwood that results when some trees, such as Aquilaria malaccensis, are attacked by fungi. This highly-prized heartwood contains a wide array of chemical compounds that fall under various classes of healthy phytochemicals such as terpenoids (monoterpenes, diterpenes and sesquiterpenoids), alkaloids, and flavonoids. Previous studies have shown promising results when Gaharu essential oils are studied for anticancer effects. However, very little information can be found on Gaharu distillates including their therapeutic effects. This study aims to determine the potential anticancer effects of Gaharu distillates on lung cancer. Calu-3 lung cancer cells were used as model cell line. They were cultured in Eagle`s Minimum Essential Medium (EMEM), supplemented with 10% (v/v) Fetal Bovine Serum (FBS). Two factor- Face-centred Central Composite Design was used to study the effects of Gaharu distillate amount and time of exposure on cell attachment (via trypan blue dye exclusion assay) as well as cytotoxicity (via MTT assay). It was found that Gaharu distillates of Aquilaria malaccensis possess both anti-attachment and cytotoxic effects on Calu-3 lung cancer cells. The best IC50 value obtained for both assays was 20, 000 ppm at 12 hours exposure time. A linear model was developed for anti-attachment effects, and a quadratic model was developed for cytotoxic effects with exposure duration being significant in both cases. This study also presents and compares profiling data from Gas Chromatography Mass Spectrometry (GCMS) and headspace Solid Phase Microextraction-Gas Chromatography Mass Spectrometry (SPME-GCMS) of the Gaharu distillates. From these profiles, 1-tricosene and 16-hentriacontanone are some of the compounds that may possess anticancer potential. In conclusion, Gaharu distillates hold a great potential to be further studied as source of anti-cancer compounds.