A 2016 study published in BMC Complementary and Alternative Medicine reports the potential use of agarwood oil extract against tumors in the colorectal region of the body. Aquilaria crassna or agarwood is widely used in perfumes, incense, and small carvings. It is already a highly prized tree and is now declared effective against colorectal cancer as well.
The researchers from “Universiti Sains Malaysia” explored the latent safety of essential oil extract from agarwood tree. They carried out animal studies in order to investigate the anti-tumor activity of the respective oil extract.
The Aquilaria genus, including A. crassna, comprises of certain trees that are called agarwood. This is because of their ability to create the eponymous resin extract. This characteristic extract is an outcome of when Aquilaria trees are damaged and molds attack the timber of the trees. The infection renders the cream-colored wood, dark and resinous which is then used in some of the world’s most expensive fragrances.
The distilled and processed version of the agarwood resin becomes “Oud oil.” It is the key ingredient in most high-end perfumes in the market and costs as high as HK$300,000 per kilogram ($17,300 per pound). People even tag it as “liquid gold.”
The traditional Malaysian medicine practitioners have been using the tree and its extract to treat vomiting, rheumatism, and even asthma. On the other side, Japanese traditional medical systems use it as a sedative and a detoxifier.
Studies reveal some more biological properties of agarwood which include its anti-ischemic, antifungal, and antibacterial uses. Moreover, A. crassna is identified as a potent antioxidant and in vitro anti-cancer plant used against colorectal carcinoma and pancreatic cancer cells. The researchers mentioned in their study that Aquilaria crassna is a useful source of bioactive constituents like phenols, flavonoids, benzophenones, xanthones, and sesquiterpenes. Moreover, no study reports the toxicological profiles of Aquilaria crassna essential oil.
The researchers carried out multiple in vivo assays in order to investigate both the toxicity and anti-tumor properties of agarwood.
For testing against acute toxicity, the researchers gave a single oral dose of 2,000 mg/kg of agarwood essential oil to mice for at least two weeks and observed the symptoms of toxicity and mortality. For the sub-chronic toxicity test, the mice were administered with differing doses of agarwood essential oil for 28 days.
Meanwhile, the researchers investigated factors such as mortality, clinical signs, body weight changes, hematological and biochemical parameters, gross findings, organ weights, and histological parameters. Moreover, the researchers used a subcutaneous tumor model in nude mice to determine the anti-tumor properties of agarwood.
The results of the tests revealed that agarwood essential oil is not toxic, even in doses greater than 2,000 mg/kg, which declares it safe to use even in substantial doses. The sub-chronic toxicity study revealed that repeated doses of agarwood essential oil had no changing effects on morbidity or mortality reported.
Both 100 mg/kg and 500 mg/kg doses of essential oil per body weight did not significantly affect the difference in,
- Food and water intakes
- Body weight change
- Hematological and biochemical parameters
- Relative organ weights
- Gross findings or histopathology
In addition, the in vivo studies investigating the anti-tumor effects of the essential oil, reported that it was able to hamper the growth of HCT 116 colorectal carcinoma cells. The research also highlighted the possible applications of essential oils in the prevention and treatment of colorectal cancer and further laid a solid foundation for their pre-clinical use in animals.