Preface

Plants rich in essential oils (EOs) are viable for use in various human activities and business sectors, particularly the food industry, due to their antioxidant, antimicrobial, phytotoxic, neuroprotective, and anti-inflammatory properties. EOs also have low cytotoxicity, which reduces the risks of intoxication. They are natural volatile fractions extracted from aromatic plants, and are formed in the secondary metabolism of plants. Several classes of volatile substances can be found in their chemical composition, such as fatty acid esters, monoterpenes, sesquiterpenes, phenylpropanoids, alcohols, aldehydes, and in some cases, aliphatic hydrocarbons. This variation in composition depends on physiology, environmental conditions, geographic variations, seasonality, collection period, genetic factors, and plant evolution. As a result, physicochemical properties of EOs can be altered, and oil concentrations in certain plant parts such as stems, leaves, flowers, and fruits can increase or decrease. In nature, EOs play a decisive role in the resistance of plants against phytopathogens and herbivores. EOs are also important in communication, for the plant can use a chemical agent that travels through the atmosphere and may activate defensive genes of other plants. In the oil industry, they are widely studied mainly for their potential applications as agents that promote biological activities. Similarly, volatile compounds have presented over the years several pharmacological properties, such as antioxidant, anticancer, antiprotozoal, antimicrobial, anti-inflammatory, phytotoxic, and neuroprotective activities. In this sense, this book provides relevant information on applications of essential oils as well as their volatile compounds, and new perspectives on their most diverse uses, aiming to contribute in a systematic way to the dissemination of knowledge in the area of natural products. The book also discusses innovative applications of EOs such as in aromatherapy, control of invasive species, and treatment of breast cancer.

The Academic Editor Dr. Mozaniel Santana de Oliveira thanks PCI-MCTIC/MPEG as well as CNPq for the scholarship process number:302203/2020-6.

**II**

**Chapter 7 123**

Antimicrobial Activity of Essential Oils **139**

**Chapter 8 141**

**Chapter 9 153**

Allelochemicals **187**

**Chapter 10 189**

Volatile Compounds, Chemical Composition and Biological Activities

*Ely Simone Cajueiro Gurgel, Willison Eduardo Oliveira Campos,* 

Chemical Composition and Antibacterial Activity of the Essential

*by José Weverton Almeida Bezerra, Felicidade Caroline Rodrigues,* 

*Marcos Aurélio Figuereido dos Santos, Gledson Ferreira Macedo, Janete de Souza Bezerra, Priscilla Augusta de Sousa Fernandes, Emanoel Messias Pereira Fernando, Carlos Henrique Silva de Oliveira,* 

Essential Oil as Antimicrobial Agents: Efficacy, Stability, and

Roles of Terpenoids in Essential Oils and Its Potential as Natural

*Viviane Bezerra da Silva, Isabella Hevily Silva Torquato, Niwiarakelly da Silva Monte, Luciano Temoteo dos Santos* 

*Antônio Pedro da Silva Souza Filho, Daniel Santiago Pereira, Sebastião Gomes Silva, Eloisa Helena de Aguiar Andrade* 

*Renan Campos e Silva, Marcos Ene Chaves Oliveira,* 

Oil of *Mesosphaerum suaveolens* (Lamiaceae)

*Ma Aparecida Barbosa Ferreira Gonçalo,* 

*and Henrique Douglas Melo Coutinho*

Safety Issues for Food Application

Weed Killers: Recent Developments *by Ahmed Abdulwahid Ali Almarie*

*by Hamdy A. Shaaban*

**Section 4**

*by Jorddy Neves Cruz, Adriane Gomes da Silva, Wanessa Almeida da Costa,* 

of *Apis mellifera* Bee Propolis

*and Mozaniel Santana de Oliveira*

**Section 3**

**Dr. Mozaniel Santana de Oliveira** Museu Emílio Goeldi, Research Campus Botanical Coordination, Pará, Brazil

**Dr. Wanessa Almeida da Costa and Dr. Sebastião Gomes Silva** Faculty of Chemical Engineering, Federal University of Pará, Pará, Brazil

**1**

Section 1

Chemical Composition

and Biological Activity

Section 1
