Lettuice, from the Asteraceae family and Lactuca genus, is a biennial herb.Lettuce can be classified into leaf lettuce and stem lettuce.The name of lettuce varies in different herbal books; it is called "Qianjin Cai","Lactuca" and，“"Shizhu".And ""Stone Lettuce".."Leaf lettuce is also known as spring lettuce or romaine, while stem lettuce is known as celery lettuce or sweet stem.In China, the cultivation area of celery lettuce is larger than that of spring lettuce.Celery lettuce has tender flesh; its stems can be eaten raw, cold-sliced, stir-fried, dried, or preserved.Spring lettuce is mainly consumed by eating its leaves or leaf balls; in recent years, it has developed particularly in major cities across southern coastal provinces of China, becoming a key vegetable to increase variety.Lettuce stems and leaves contain lactucin, which tastes bitter; the bitterness intensifies during high temperatures and droughts, enhancing stomach acid secretion, stimulating digestion, increasing appetite, and
