Protocatechuic acid (PCA) is 3,4-dihydroxybenzoic acid. It is a simple phenolic acid, which is the precursor for the synthesis of other complex molecules, such as anthocyanin 3-O-β-D-glucoside and vanillin. It is found in edible vegetables, fruits, nuts, brown rice, pecans, tea, hibiscus flowers and some Chinese herbal medicines. 

Protocatechuic acid has a variety of biological activities against different molecular targets. It has antibacterial, anti-oxidant, anti-inflammatory, anti-hyperglycemic and neuroprotective effects. In addition, protocatechuic acid has potential chemical protective effects. It can inhibit chemical carcinogens in vitro and produce pro-apoptosis and anti-proliferation effects in different aspects. Therefore, it is currently used clinically for the treatment of burns, pediatric pneumonia, bacillary dysentery, acute pyelonephritis, acute pancreatitis and certain ulcer diseases.

Effects of Protocatechuic acid

Protocatechuic acid is a metabolite of complex polyphenols, such as anthocyanins and proanthocyanidins. A large number of experiments have proved that protocatechuic acid has a variety of biological activities against different molecular targets. It has antibacterial, antioxidant, anti-inflammatory, anti-hyperglycemic and neuroprotective effects. In addition, protocatechin has potential chemical Protective effect, it can inhibit chemical carcinogens in vitro and produce pro-apoptosis and anti-proliferation effects in different aspects.

1. Protocatechin antibacterial effect

Protocatechuic acid has a wide range of antibacterial effects. Protocatechuic acid isolated from the plant Roselle, in in vitro experiments, is resistant to methicillin-resistant Staphylococcus aureus, pneumoniae bacteria, and Pseudomonas aeruginosa And Acinetobacter baumannii has an inhibitory effect, and the antibacterial ability of protocatechuic acid is better than that of Roselle. Heat-treated protocatechuic acid does not affect its antibacterial activity. 

2. Anti-cancer effect of protocatechin

Protocatechuic acid has a certain effect on cancer prevention, and its mechanism of action may be related to its antioxidant activity, including growth inhibition, scavenging of oxygen free radicals and up-regulation of enzymes involved in neutralization, or it affects the primary and secondary phases of some carcinogens. 

3. Antioxidant effect of protocatechuic acid

Alpinia protocatechuic acid reduces the survival rate of cells induced by hydrogen peroxide in vitro, prevents oxidative damage, and can reduce oxidative stress in the body. Its protective effect may be through antiperoxidase activity and inhibition Promoted by the generation of free radicals.

4. Anti-inflammatory effects of protocatechuic acid

Protocatechuic acid has an anti-inflammatory effect. It has a protective effect on LPS-induced RAW-264.7 cells and carrageenan-induced air bag models in mice. In addition, protocatechuic acid is an important active ingredient in Sijiqing tablets used as antibacterial and anti-inflammatory.

5. The anti-hyperglycemic effect of protocatechin

In diabetic mice, protocatechin significantly reduces blood sugar levels and increases insulin levels. The reason may be that protocatechin reduces the complications of diabetes, lowers triglycerides, and exerts its antioxidant and anti-inflammatory effects. Protocatechin is beneficial to prevent or alleviate the related glycation of diabetes complications.

6. Other effects of protocatechuic acid

Protocatechuic acid can potentially resist infectious bursal bursal virus. Protocatechuic acid can effectively reduce atherogenesis in mice lacking apolipoprotein E. Protocatechin can prevent the reproductive toxicity of male rats induced by dioxin.