THE EFFECTIVENESS OF LEMON GRASS AS NATURAL INSECT REPELLANT

THE EFFECTIVENESS OF LEMON GRASS AS NATURAL INSECT REPELLANT

CHAPTER ONE

1.0     INTRODUCTION

Lemongrass (cymbopogom citratus) is a genus of a about 55 related grass species or varieties. The lemongrass plant or the oil extracted from it is used in cooking, aromatherapy, medicinal preparations, teas and cosmetics. Lemon grass also has insecticidal properties and the extracted oil is used in insect repellants and insecticidal sprays. The same chemical compounds are found in some lemon grass varieties, but the aroma may differ. Citronella oil, a common mosquito repellant is extracted from citronella grass (lemon grass).

Lemon grass oil used as a pesticide and a preservative. Lemongrass oil has antifungal properties despite its ability to repel insects, such as mosquitoes, its oil is commonly used as a “lure”to attract honey bees. Lemon grass works conveniently as the pheromone created by the honeybees Nasonov gland also known as attractant pheromone. Because of this, lemon grass oil can be used as a lure when trapping swarms or attempting to draw the attention of hived bees.

1.1 BACKGROUND

Insect repellants are important public health tools for the prevention of vector-borne infectious diseases. Actions to reduce vector-borne diseases can result in major health gains and relieve an important constraint on development in poor regions. Insect repellants help to prevent and control the outbreaks of insect-borne diseases such as malaria, lyme disease, dengue fever and bubonic plaque (Wikipedia, 2011).

Lemon grass is very popular and used for medicinal, food and insect repellant products. The lemon grass oils are used in cosmetics, soaps, perfumes, dyes, odourizers along with thousands of other products. Lemon grass has thin stems, and the flowers are white, cream or green. It grows about 8 feet in height in some cases with the majority of species tapering at 4 feet.

Lemon grass is mainly found in tropical Asia countries such as India, Brazil, Philippine, Malaysia, Myanmar, Guatemala, Madagascar, Mauritius, New Guinea and countries in Africa and South America.

In the Philippines, it has a local name known as “tauglad”. Many repellant products pertaining active chemical compound like DEET (N,N-Diethyl-metatoluamide) used as active chemical ingredient in insect repellant, are now turn to all natural ingredients as the EPA’s GRAS lists (Generally regarded as safe). People all over the world have come to rely on the potent insect repellant properties of lemon grass and utilize it as a personal and area spray. Lemon grass oil used as a pesticide and preservative is put on the ancient palm-leaf manuscript found in India as a preservative. It is used at the oriental research institute Mysore, the French institute of Pondicherry, the association for the preservation of the saint Thomas Christian Haritage in Korala and many other manuscripts collections in India. The oil also injects natural fluidity into the brittle palm leaves and the hydrophobic nature of the oil keeps the manuscripts dry so the text is not lost to decay due to humidity.

1.2 Aim and objective

The objective of this study is to determine the effectiveness of lemon grass as natural insect repellant. To observe the time and duration of the effectiveness of lemon grass oil at different concentration as an insect repellant.

1.3 SIGNIFICANCE OF STUDY

This study will produce significant and relevant information for future studies regarding to insect repellant.

1.4 LIMITATION/ SAFETY
1.4.1 SAFETY

At low doses, lemon grasses oil is non-toxic. The intrinsic longtime and widespread use of lemon grasses oil all over the world also speaks of its safety. As a natural insecticide, lemon grass and its oil are not associated with some of the toxic or harmful side effect of be used of other insecticides.

1.4.2    LIMITATION

The lemon grasss oil should not be used internally by children, women who are pregnant, lactating mothers or people with liver and kidney disease. When used for various medication, there will be reports of the following:

Burning sensation (s)

Skin irritation, discomfort and rash

Lowered blood glucose

CHAPTER TWO

2.0      LITERATURE REVIEW

The genus cymbopogon  belongs to the grass family, poaceae. The poceae family has about 700 genera and 11,000 species widely distributed in a regions of the world.Cymbopogon is genus comprising about 180 species, subspecies, variety and sub varieties (Bertea and Maffei, 2010). Cymbopon species found within the aromatherapy industry include; C. citrates (lemon grass), C. Martinni var, Motia and Sofia (Palmarosa and ginger grass), C. flexuosus (lemon grass), C. Winterianus (Java Citonella), C. nardus (Ceylon citronella) and C. nardus x C. Jwarancusa (Jamrose).

There are two main types of lemon grasses; East Indian lemon grass (cymbopon flexuosus) (Nees steud and J.F Watson, 2010) which is consider to have its origin in southern Indian and West Indian lemon grass (cymbopon citratus) which is thought to have its origin in Malaysia and is mainly cultivated in central and South America and parts of Africa, south East Asia and the India Ocean islands. Both species produce an essential oil rich in Citral.