**6. Botanical oil microemulsion in crop protection with emphasis on essential oil**

Several botanicals sources of phytochemicals offer great promise for insect pest control. Six plant families with several representative species, Asteraceae, Cladophoraceae, Labiatae, Meliaceae, Oocystaceae, and Rutaceae, appear to have the most significant potential for providing future insect control in crops [6].

A most crucial source of phytochemical compounds against insect pests is the essential oil. Essential oil is the mixture of volatile compounds generally produced by Plant as secondary metabolites, constituted by hydrocarbons (terpenes and sesquiterpenes) and oxygenated compounds (alcohols, esters, ethers, aldehydes, ketones, lactones, and phenols) [7]. Bioactive chemical compounds of essential oils have repellent properties against mosquitoes. Previous studies revealed that terpenoid groups are biologically active compounds for mosquito repellency. There are 20 active terpenoids with a functional group of negatively charged and containing ester/ether bonds or an ethanol hydroxyl group and other positively charged end containing alkane groups [8]. These bio-active chemicals have several properties, which are categorized as repellents, feeding deterrents, toxins, and growth

*Microemulsion Formulation of Botanical Oils as an Efficient Tool to Provide Sustainable… DOI: http://dx.doi.org/10.5772/intechopen.91788*

regulators. Five major categories of bioactive compounds are (1) nitrogen compounds (primarily alkaloids), (2) terpenoids, (3) phenolics, (4) proteinase inhibitors, and (5) growth regulators [9].

Many bioactive compounds (phytochemicals) have been discovered by the researchers who have good repellent activity against insect pests [10]. These botanical-based repellents not only have excellent repellency but also influences the physiology of insect. These botanical bioactive agents (phytochemicals) can effectively replace the presently available synthetic pesticides against the mosquito.

## **6.1 Issues with essential oils in agriculture**

**5. Applications of microemulsion**

Microemulsion are being used in many areas.

*Nano- and Microencapsulation - Techniques and Applications*

for various constituent detection.

due to the high amount of surfactants.

its applications in the following fields:

• Environmental Remediation

systems.

• Cosmetics

• Detergents

• Agrochemicals

**on essential oil**

• Food

**268**

• Coating of Textiles

a. **Drug delivery**: Microemulsion formulation has been extensively used in drug delivery. From the last few decades, the microemulsion system has been used in a variety of drug delivery systems like oral, topical, parenteral, and oral.

solubilizing medium for hydrophobic constituents and then can be analyzed

d. **Oil recovery**: The microemulsion system also helps in the improvement of oil

Besides, the applications mentioned above, microemulsion formulation also find

b. **Analytical applications**: The microemulsion system is the suitable

c. **Biotechnology applications**: Enzymatic reaction, immobilization of proteins, and bioseparation can be done successfully in microemulsion

**6. Botanical oil microemulsion in crop protection with emphasis**

control. Six plant families with several representative species, Asteraceae, Cladophoraceae, Labiatae, Meliaceae, Oocystaceae, and Rutaceae, appear to have the most significant potential for providing future insect control in crops [6]. A most crucial source of phytochemical compounds against insect pests is the essential oil. Essential oil is the mixture of volatile compounds generally produced by Plant as secondary metabolites, constituted by hydrocarbons (terpenes and sesquiterpenes) and oxygenated compounds (alcohols, esters, ethers, aldehydes, ketones, lactones, and phenols) [7]. Bioactive chemical compounds of essential oils have repellent properties against mosquitoes. Previous studies revealed that terpenoid groups are biologically active compounds for mosquito repellency. There are 20 active terpenoids with a functional group of negatively charged and containing ester/ether bonds or an ethanol hydroxyl group and other positively charged end containing alkane groups [8]. These bio-active chemicals have several properties, which are categorized as repellents, feeding deterrents, toxins, and growth

Several botanicals sources of phytochemicals offer great promise for insect pest

Essentials are potent pesticides. But still, exploitation of them in pure form is not encouragable in the agriculture because of the following reasons:

