Inhibitory Properties of Phenolic Compounds Against Enzymes Linked with Human Diseases

Some drugs currently used are inhibitors of enzymes involved in mediating many disease processes. Concerns over the toxicity and side effects of synthetic enzyme inhibitors have led to a search for new safe and effective inhibitors particularly from natural sources. Owing to their wide range of biological effects, plant phenolic compounds are one of the most studied families of natural products. This chapter aims to provide an overview of the potential of phenolic compounds as enzyme inhibitors. Extensive research has been conducted to study the enzyme inhibitory capacity of many phenolic compounds against several enzymes linked with important human conditions. Investigations conducted are mainly focused on the inhibition of angiotensin I-converting enzyme, α-amylase and α-glucosidase, lipase, cholinesterases, proinflammatory enzymes (cyclooxygenases and 5-lipoxygenase) and tyrosinase, which are related with hypertension, type II diabetes, obesity, Alzheimer’s diseases, inflammation and skin hyperpigmentation, respectively. Overall, among phenolics, flavonoids are probably those with great capacity to inhibit the activity of the enzymes revised. Several studies demonstrated the potent antioxidant and anti-inflammatory properties of flavonoids, which highlight the therapeutic poten - tial of these compounds. Although our literature survey showed that a huge number of phenolic compounds have been studied and there are some promising compounds depending on the enzyme, more in vivo tests and subsequent steps to be a drug candidate are required before therapeutic application.