The natural material resources used for the development of antioxidants are very extensive, which can be summarized into the following categories:
1. Spices: a kind of natural plant products with typical flavors such as aromatic and spicy, or some essential oils extracted from plants (flowers, leaves, stems, roots, fruits or whole plants, etc.). In recent decades, spices Antioxidant properties have received extensive attention and research. The main antioxidant components of spices are phenols and their derivatives.
2. Chinese herbal medicine: The efficacy of certain Chinese herbal medicines is closely related to their antioxidant effects. Chinese herbal medicines are another potential natural antioxidant resource after spices.
3. Tea: Tea is rich in a class of polyphenolic substances called tea polyphenols. It is a class of polyphenols with catechins as the main body, and their basic structure is 2-continuous (or o) phenolic benzene. Dipyran derivatives are a new type of natural antioxidants.
4. Foods: Cereals and edible oils are the earliest scientific research objects used as natural antioxidants. Many fruits and vegetables also show excellent antioxidant properties. Onions, peppers and coltsfoot stems have strong antioxidant capacity and most vegetables have weak antioxidant capacity. The antioxidant components of several fruits are mainly flavonoids, ascorbic acid and other organic acids.
5. Other raw materials: luteolin in peanut shell, galangal extract in galangal, rutin in sophora rice, apigenin in oregano grass, celestin in jindiluo, etc. belong to flavonoids, they are anti-oxidant to oil The activity is equal to or higher than the BHT effect. Soybeans, rice husks, and green barley leaves also contain flavonoids, which all have good antioxidant capacity. Protein hydrolysates, amino acids and Maillard reaction products are also of interest. After the soybean protein was hydrolyzed to different degrees, it was found that the hydrolyzed degree of 177% component has strong antioxidant effect. Proline, tryptophan, histidine, tyrosine, methionine and other antioxidant properties are strong. Bacteria and yeast are also used by some scholars to extract antioxidants. A colorless crystal antioxidant was isolated from the mixture of baker's yeast and stele yeast, and its structure has been confirmed. Algae have antioxidant properties. Among them, brown algae and green algae have strong antioxidant capacity. The antioxidant components separated and refined from them include pheophytin a, phospholipids, and olfactory phenolic compounds.