The epidermal growth factor （EGF） has been shown to promote the proliferation of various types of cells, to maintain the physiological function of the mucosa of the digestive tract, and to promote the healing of the gastric and duodenal ulcers. It has been expressed in many types of bacteria and yeasts. In this article, a bio-reactor was constructed, namely, the human EGF （hEGF） transgenic mini-tomato. On the basis of hEGF gene sequence, a tomato codon preference hEGF gene was chemically synthesized, and it was constructed into the plant expression vector pCAMBIA2300. The transgenic tomato plants containing gene hEGF were obtained through Agrobacterium-mediated transformation. The expression product was determined by radioimmunoassay （RIA） and showed a yield of 3.48± 1.01 ng/g fresh fruits. The intragastric gavage （ig） administration of the rhEGF-containing juice of the transgenic tomato （equivalent to 24 ng rhEGF per mouse a day） for 15 days could significantly protect mice against the alcohol-induced ulceration. The ulcer index, expressed as a degree of the stomach lesion, decreased from 42.20 ±18.13 to 16.25 ±9.57.
