[Function]D-alanine is one important organic chiral source, it is be used in chiral medicine, chiral additives, and it is chiral source of chiral synthesis in pharmaceutical and food industry. As one organic acid with optical activity, D-alanine has irreplaceable function in some chiral chemical compound `s asymmetrical combined sequence. And now, D-alanine is used to manufacture new kind of broad-spectrum antibiotic, D-alaninol and compound new sweetness-Alitame.