Less well known is that research is also continuing into the scent of repellents to deter pests like insects and ticks. Various plants are known for the effects of their aroma, and are in widespread use for protection, especially in very hot and humid climates where there are a great number of arthropods; for instance, it is known that mosquitoes will not approach a house that has basil plants on the windowsill.
Another plant which is well known and used commonly for its scent is “patchouli” (pogostemon cablin), the scented essential oil of which is obtained by steaming the plant and collecting the oil which emerges. The plant is a member of the mint family, and its actual origin is India, where its scent can be found even in the famous Indian ink. Patchouli leaves used to be placed between carpets and rugs made in Iran and Turkey to protect them from any harmful pests or insects before they were sent to Europe. During the Victorian period carpets, shawls and rugs exported from India were also sprinkled with the fragrance of patchouli to protect them from moth, In fact any carpets, rugs or shawls that did not have the scent of patchouli were not favored because they were believed to have been manufactured in Europe. The fragrance of the plant, which is longer lasting than most other scents, is believed by the Chinese, Japanese and Arabs to prevent the spread of infectious diseases and also used frequently in perfumes and soaps. Widely used in Europe in the eighteen hundreds, patchouli became the most popular fragrance of the generation in America in the sixties.
The research into patchouli has been limited so far and scientific observations are insufficient; nevertheless, the chemical composition of the various scents found in the oil of this plant have been identified, and the long human experiences of using this plant and its fragrance may hold great significance for scientific research in the future.
The plant contains patchouli alcohol, pogostone, friedelin, epifriedelinol, pachypodol, retusin, oleanolic asid, beta-sitosterol and daucosterol, most of which prevent nausea. It has also been found to contain alpha-bulnesene, which prevents the clotting of blood. In addition, according to an article in the 2008 February edition of the Phytotherapy research journal, since the oil obtained from patchouli essence is an effective fly killer, the oil could also be an effective as a component of insect repellents and might even be an effective arthropod and tick repellent.
Looking at these studies we clearly see other ways in which we could benefit from this substance; for instance, by adding a few drops to water we could use it in household cleaning and therefore get rid of unwanted odors at the same time as preventing insects in the home without the use of carcinogenic chemicals. The oil is also known to be used to prevent fungus, to reduce perspiration and eliminate unwanted body odors and for dietary purposes, due to its effectiveness in reducing the appetite.
Moreover, patchouli has also long been a fragrance very much sought and used as a form of treatment for its soothing qualities and positive effect on spiritual health. Martin Henglein, who was one of the founders of aromatherapy and developer of the theory of the curative aspect of the fragrances of plants, recognizes geranium, rosemary, bergamot, and patchouli as the four primary aromas, and he emphasizes that these four fragrances perform various functions. Geranium can prevent addictions from progressing and even assist people in abandoning addictions and bad habits. For instance, the role geranium plays in giving up smoking is indisputable: when the desire to smoke increases and becomes unbearable the aroma of geranium temporarily eliminates the desire to smoke. According to Henglein, rosemary improves memory while bergamot increases activity in the brain and the ability to understand; patchouli activates the mechanism which motivates a person’s energy.
Robert Tisserand, owner of a treatment center in England, believes that certain fragrances can also cure psychological illnesses, Tisserand says that these aromas have a positive effect on the signal molecules (neurotransmitters) that provide communication with the nerve cells and can help to cure psychological problems. Fragrances encourage the body to release endorphin, a substance which resembles morphine (a pain reliever) and this is why rose oil, jasmine, sage, cananga (ylang ylang), patchouli, and grapefruit are recommended for depression, to increase confidence, and to help with abnormalities of sexual function. If patchouli is used in excess, it allegedly may cause a sedative effect or may reduce sleep. Otherwise, it is claimed to have a balancing effect on the body’s energy and psychological condition, inspire a sense of calmness, eliminate laziness, support treatment of addictions, and relieve feelings of fear and depression.
Everyone knows that charming fragrances enhance positive thought and feelings, and we also know the negative aspects of bad odors. It is reported that the Prophet Muhammad, peace be upon him, said, “I have been made to love perfume,” drawing attention to the importance of pleasant fragrances and reminding us that Jacob received the glad tidings that his son Joseph was still alive because of the scent of his shirt.
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