Geraniol is a monoterpenoid as well as an alcohol, which is chemically classified in allergens. Following oxidation, geraniol changes to citral or geranial. The color of geraniol varies from transparent to light yellow. This oil has an aroma similar to that of rose. Apart from being used as an ingredient in perfume making, geraniol is also employed in different flavours including plum, citrus fruits, blueberry, raspberry, peach, watermelon and pineapple. Geraniol is also used in cosmetics as well as personal care products, such as in the formulations of bath products, aftershave lotions, bubble baths, lipsticks, hair care products, perfumes, colognes, moisturizers, skin care and suntan products.
Geraniol is present in geranium and pelargonium and these plants can be found in all places having temperate climatic conditions as well as the mountainous regions in the tropics. They are also found in various parts of South Africa. However, it is mostly found in the eastern region of the Mediterranean. A flowering plant genus, pelargonium includes nearly 200 species, including perennials, shrubs and succulents, which are generally called aromatic geraniums or storksbills.
This acyclic monoterpene-alcohol is also found in small quantities in geranium, lemon as well as several other essential oils. Perhaps, geraniol was first discovered in geranium from which it got its name. The scent of geraniol is akin to that of roses. Often, geraniol is used to reproduce the flavour of several fruits. Generally, it is used in the form of a flavoring agent. Apart from the above mentioned uses of geraniol, this substance is also an excellent mosquito repellent. However, the smell of geraniol attracts bees. Geraniol is also used in small amounts in cigarettes to augment their flavour. Geraniol also possesses a number of therapeutic properties – it is reported to possess antioxidant attributes, in addition to having anti-carcinogenic effects on living organisms.
Most of us are aware that antioxidants help to put off oxidative damage attributed to detrimental free radicals and, hence, it can be used for treating cardiovascular as well as anti-inflammatory diseases. It is worth mentioning here that natural antioxidants are used in place of synthetic antioxidants to inhibit lipid oxidation in various foods with a view to augment their quality as well as nutritional worth. Aside from being used in the form of an aromatic additive in foods, essential oils obtained from plants belonging to genus pelargonium also possess antioxidant attributes. In a research undertaken to ascertain the antioxidant actions of geraniol, two corresponding test systems employed gingerol, geranial acetate and eugenol. These two complementary test systems, specifically 2,2-diphenyl-1-picrylhydrazyl (also referred to as DPPH) free radical foraging and super oxide dismutase (also referred to as SOD) activity found that geraniol’s antioxidant activities were superior to that of others in DPPH trials.
It was found that the antioxidant activity of eugenol was higher in super oxide dismutase (SOD) activity. Even these essential oils demonstrated that they were a potential source of natural antioxidants. In fact, these findings scientifically corroborate the ethno pharmacologic uses of these essential oils.
Geraniol is an unsteady allergen. However, this compound is often employed in elevated concentrations. It has been found that about 9.5 percent of people using cosmetics containing this substance can suffer from allergic reactions. However, it is really difficult to stay away from this compound as it is present in various different types of cosmetic products, even cosmetics that are used by children. Geraniol is present even in natural or organic cosmetics.
As mentioned in the beginning of this article, geraniol is both – a monoterpenoid as well as an alcohol. It forms a major constituent of rose oil, citronella oil (Java type) and palmarosa oil. The appearance of geraniol is akin to that of light yellow oil, which does not dissolve in water. However, geraniol is soluble in nearly all familiar organic solvents. The aroma of this oil is similar to that of roses and is generally employed in perfumes.
Commercially, geraniol is a very important terpene alcohol that occurs naturally in essential oils obtained from many aromatic plants. This is among the most important compounds used by the fragrance and flavor industries. Geraniol forms a familiar ingredient in various consumer products made by the fragrance and flavour industries. Aside from its pleasing aroma, geraniol possesses insecticidal as well as repellent properties and is widely employed in the form of a natural pest control agent having very low toxicity. In recent times, geraniol has been recommended as a new category of chemoprevention agent for treating cancer. Apart from the uses of geraniol discussed above, this compound is also employed for several other purposes, for instance in the form of an antioxidant, anti-microbial and anti-inflammatory agent. Scientists are also examining the vascular effects of this natural compound.
Geraniol has also attracted the attention of researchers as well as formulation scientists for its use as a penetration enhancer in delivering transdermal drugs. The purpose of this article is to comprehensively discuss a few of the most vital uses of geraniol and unite the findings of several studies that reveal the biological attributed of geraniol.
Geraniol as well as other monoterpenes present in several essential oils extracted from herbs and fruits are said to represent a new group of cancer chemo preventive agents. At first, researchers studied the effects of geraniol on colon cancer cell line growth in humans with a view to shed light on the manner in which this natural compound affects colon carcinogenesis. It was found that application of geraniol (400 microM) reduced the cancer cell growth by 70 percent. Researchers also found that geraniol caused the cells to accumulate in cell cycle’s S transition phase and, at the same time, it also restrained DNA synthesis. However, they did not find any sign of apoptosis or cytotoxicity owing to the application of geraniol.
During the course of their study, researchers also found that application of geraniol also decreased ornithine decarboxylase activity by about 50 percent. Ornithine decarboxylase is considered to be a vital enzyme derived from polyamine biosynthesis, which is augmented in cancer growth. As a result, it has caused about 40 percent decrease in the pool of intra-cellular putrescence.
In addition, geraniol also triggered polyamine catabolism inside the cells and this was indicated by improved polyamine acetylation. Observations like these suggest that apparently intracellular polyamine metabolism is one of the aims of geraniol’s anti-proliferative attributes.
Geraniol is transformed into a substance known as cyclic terpene alpha-terpineol in acidic solutions.
Findings of a number of studies have demonstrated that geraniol is an effectual natural mosquito repellent derived from plants. Then again, the downside is that geraniol can draw bees, since it is made by the honey bees’ scent glands in order to help them identify the flowers containing nectar and also find the openings to their hives.
While geraniol as well as other favouring agents occur naturally in adequately matured tobacco a 1994 report prepared by cigarette manufacturing companies lists geraniol among the 599 additives used in cigarette to enhance their flavor. In addition, the fragrance industry has been using geraniol to produce perfumes, lotions, creams, soaps and detergents since long.
Since long, geraniol has been used by the food industry in the form of a flavoring agent both in alcoholic as well as non-alcoholic beverages. Traditionally, this compound has also been used in candies, ice cream and baked goods. It is worth mentioning here that the safety record of geraniol is extensive, as it is used as bait in beetle traps in Japan.
Being a natural antioxidant, geraniol is said to be useful in preventing various types of cancer. It has been found that geraniol slows down synthesis of DNA.
Moreover, geraniol along with perill and farnesol alcohol is known to hold back growth of pancreatic tumours. Findings of several studies undertaken on animals have also shown that geraniol possesses anti-cancer activities.
Apart from the above mentioned health benefits of geraniol, this acyclic monoterpene-alcohol is widely used in a number of skin care products and even perfumes. Currently, researchers are examining the anti-tumour effects of geraniol.