# Plant-Derived Phytobiotics as Emerging Alternatives to Antibiotics Against Foodborne Pathogens
### Phenolic Compounds
#### 2.1.1 Simple Phenolic Compounds  
Class of phenolic compounds, which contain one phenol unit (or its derivative). They have a general C6 backbone representation--a benzene ring with one or more hydroxyl (-OH) groups directly attached to it. Simple phenolic compounds are found in a variety of plant-based foods, including fruits, vegetables, legumes, cereals, seeds, and beverages such as coffee, tea, and wine [17]. These include simple phenols--the simplest forms of phenolic compounds, belonging to hydroxyphenols, dihydroxybenzenes (e.g., resorcinol, catechol, and hydroquinone), dihydroxyphenols or trihydroxybenzenes (e.g., hydroxyquinol, pygallol, and phloroglucinol).  
\begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline
**Compound Group** & **Examples** & **Key Properties** & **Main Sources** \\ \hline \multirow{2}{*}{Terpenes} & Mono- and sesquiterpenes & Antimicrobial, antioxidant, and flavoring agents & Essential oils and oleoresins [2; 11] \\ \hline \multirow{2}{*}{Organosulfur compounds} & Allicin and glucosinolates & Antimicrobial, antioxidant, and anti-inflammatory & Garlic, onions, and cruciferous vegetables [2; 12] \\ \hline \multirow{2}{*}{Alkaloids} & Berberine and quinine & Antimicrobial and anti-inflammatory & Various medicinal plants [1; 12] \\ \hline \multirow{2}{*}{Phytosterols} & Beta-sitosterol and campesterol & Cholesterol-lowering and anti-inflammatory & Vegetable oils, nuts, and seeds [12] \\ \hline \multirow{4}{*}{Saponins} & Diosgenin and ginseng & Antimicrobial, immune-modulating, and cholesterol-lowering & Legumes, soybeans, quinoa, and ginseng [2] \\ \hline \multirow{2}{*}{Polysaccharides} & Beta-glucans and arabinadactans & Immune-stimulating and prebiotic & Mushrooms, oats, and barley [13] \\ \hline \end{tabular}
\end{table}
Table 1: _Cont._Simple phenolic compounds also include carboxylic acid-containing phenols, known as phenolic acids. Phenolic acids include two main subgroups: hydroxybenzoic acids, with a general structure of the C6-C1 type (e.g., gallic acid, p-hydroxybenzoic acid, protocatechic acid), and hydroxycinnamic acids, which have a C6-C3 skeleton (e.g., caffeic acid, synaptic acid, ferulic acid, p-coumaric acid, cinnamic acid) [14]. Phenolic acids are widely distributed among plants such as fruits, vegetables, spices, and grains and are also present in beverages such as coffee and tea. In plants, these compounds play a role in defense against pathogens and environmental stress. These phytochemicals are known for their beneficial effects on human health, including their antioxidant, antibacterial, antiviral, and anti-inflammatory properties, as well as anti-cancer, anti-atherogenic, and cardioprotective properties [18].  
According to some classifications, simple phenolic compounds also include coumarins, based on the presence of an aromatic structure with a hydroxyl group. These compounds are widely distributed in the vascular bundles of plants and exhibit activity against herbivores. Coumarins are a group of broad-spectrum compounds that have applications in pharmacology, the food industry, and agriculture and exhibit a range of biological activities [19]. Frequently mentioned chemical compounds in this group are umbelliferone and scopoletin. Another representative of coumarins is 7-hydroxycoumarin, which is found in coriander, carrots, and garden angelica. A subgroup of coumarins, called furanocoumarins, is found in plants of the _Apiaceae_ family, such as psoraline, which exhibits antifungal properties and phytotoxicity [20].