Plants are rich in essential oils (EOs). They are used in many industries, especially in the food industry, due to their antioxidant, antimicrobial, phytotoxic, neuroprotective, and anti-inflammatory properties. EOs also have low cytotoxicity, which reduces the risk 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 the composition depends on physiology, environmental conditions, geographic variations, seasonality, collection period, genetic factors, and plant evolution. As a result, the 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 to 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 the 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 been studied over the years for their several pharmacological properties, such as their antioxidant, anticancer, antimicrobial properties. The antimicrobial activities of essential oils are essential. They are widely applied in the pharmaceutical industry and in the food industry. In the pharmaceutical industry, essential oils can act as potential suppliers of new active molecules to help fight against resistant pathogens (fungi and bacteria). Meanwhile, in the food industry, they can help in maintaining quality characteristics. They could potentially become a natural preservative for food packaging, or they can be used for encapsulation and controlled release. The search for a healthier and more natural diet has led humans to consume less processed foods and seek alternative methods such as the use of herbal medicines.

The aim of this Special Issue is to bring together original research and review articles providing relevant information on the antimicrobial properties of essential oils. Submissions should consider the volatile compounds of essential oils and bring new perspectives about their use. We hope that this Special Issue provides a platform for researchers to help them disseminate their knowledge about natural products.

Potential topics include but are not limited to the following:

• Antimicrobial activity of essential oils
• Antimicrobial activity of essential oils and essential oil components in relation to oral bacteria
• Toxicity of essential oils
• Encapsulated essential oils with antimicrobial activity
• Antimicrobial activity of chitosan films enriched with essential oils
• Essential oils with potential antifungal activity
• Essential oils with antibacterial activity
• Mechanism of action of essential oils in fungi and bacteria
• Antimicrobial activity of essential oils from medicinal plants
• Antimicrobial activity and chemical composition of essential oils
• Volatile compounds with antimicrobial activity