3,4-dihydroxybenzoic acid can be found in the leaves of Holly, lepidopteris and other substances. As a commodity, 3,4-dihydroxybenzoic acid has a white powdery appearance and changes color when exposed to air. Aqueous solutions of 3,4-dihydroxybenzoic acid turn dark red in the presence of sodium bicarbonate and green in the presence of ferric chloride.
3,4-dihydroxybenzoic acid has a variety of biological activities, can play antioxidant, antibacterial, nerve protection, hypoglycemia and other functions, so it is widely used in the medical field. In addition, 3,4-dihydroxybenzoic acid can also be used in feed, cosmetics and other industries.
In the field of feed, 3,4-dihydroxybenzoic acid as feed additive can not only promote the growth and development of livestock and poultry, improve immune function and defense ability, improve meat quality and flavor of livestock and poultry.
Although 3,4-dihydroxybenzoic acid can be found in some plants, the number of plants that can be used as extraction sources is small and the content is low, which is not suitable for large-scale production. Compared with chemical method to produce protocatechuic acid, biological method is more environmentally friendly, sustainable and more in line with modern production needs.