L-threonine is widely used in medicine, food, cosmetics and other fields. In medicine, L-threonine can be used as a specific zipper break inducer of deoxyribonucleic acid (DNA) and is used to treat certain cancers. In the food industry, L-threonine can be used as an additive to enhance the flavor of food, such as increasing the aroma of biscuits, biscuits and pastries. In the field of cosmetics, L-threonine can be used in products such as skin care products and shampoos to moisturize and protect the skin.