Medicinal plants are currently of considerable importance because they can be used for therapeutic purposes in many medical systems and are increasingly becoming a substitute for synthetic drugs in modern society. Medicinal plants possess therapeutic activities in many areas, such as anti-bacterial, anti-oxidation, anti-microbial, anti-inflammatory, anti-cancer, and other activities. Therefore, extracts from medicinal plants offer unlimited opportunities for new drugs because of the availability and chemical diversity of biological active principles from the plants.

Applications

• Anti-oxidation: There are oxidation systems and anti-oxidant systems in the body. Under normal conditions, these two systems are in dynamic equilibrium. When the antioxidant system cannot remove free radicals and toxic products they metabolize, oxidative stress occurs. Oxidative stress can have various adverse effects on the body. Excessive accumulation of oxidizing substances in the body not only causes various metabolic diseases, but also causes lipid peroxidation, which in turn causes damage to lipids in cells and organelle membranes. Polyphenolic compounds contained in plants have anti-oxidant effects, and studies have shown that various plant extracts contain different types and amounts of polyphenols. There are many types of polyphenolic compounds, including hydroxybenzoic acid, hydroxycinnamic acid, anthocyanins, lignans, flavonols, and flavonoids.

Figure 1. Ellagic acid is a natural polyphenol antioxidant found in plants.

• Anti-bacterial: Plant extracts isolated from plants used as traditional medicines are considered to be good substitutes for chemical synthesized antibacterials. For example, traditional medicinal plant extracts or phytochemicals have been shown to inhibit the growth of oral pathogens, reduce the occurrence of dental plaque, affect the adhesion of bacteria to the tooth surface, and alleviate the symptoms of oral diseases.
• Antimicrobial: Data on the antimicrobial activity of many plants along with reports of pathogenic microorganisms that are resistant to antimicrobials have been scientifically proven. Extracts from plants may potentially control the growth of microorganisms in different situations. In one study, the inhibitory activity of concentrates from 14 plants against methicillin-resistant Staphylococcus aureus strains was analyzed. The substances having inhibitory activity are present in the fractionsand parts of T. avellanedae wood.
• Anti-cancer: Scientific and research interests are drawing attention to natural compounds because they are considered to have lower toxic side effects than current chemotherapy. The plants are considered to be able to produce naturally occurring secondary metabolites and their anticancer activities may help develop new clinical drugs. Plant extracts having anticancer properties extracted from terrestrial plants contain compounds such as polyphenolic compounds and paclitaxel compounds.

Figure 2. The structure of paclitaxel.