The configurations of the component amino acids in ginseng tetrapeptide 1 isolated from Panax ginseng were determined by HPLC with an optical resolution column and the structure of 1 was established to be H-L-Val-gamma-D-Glu-D-Arg- Gly-OH. Synthesis of the ginseng tetrapeptide, 1, and of the configuration and conjugation isomers, H-L-Val-gamma-L-Glu-L-Arg-Gly-OH (2), H-L-Val-D-Glu- D-Arg-Gly-OH (3), and H-L-Val-L-Glu-L-Arg-Gly-OH (4) was carried out by a solid-phase method using the Fmoc strategy. The effects of 1-4 on the proliferation of baby hamster kidney (BHK)-21 cells, normal female bronchiogenic epithelioid (CCD-14 Br) cells, and normal human epidermal fibroblast (NB1 RGB) were examined. Only 1 showed 32 and 23% enhancement of BHK-21 and human CCD-14 Br cells growth, respectively, at a concentration of 13.6 microM and 41% enhancement of NB1 RGB cells growth at a concentration of 32 microM under the conditions employed. It was shown that both the configuration of the component amino acids and the peptide conjugation at a gamma-position of D-Glu in 1 are important for proliferation of the cells. Compound 1 exerted a prominent effect on cell stimulation and growth rate without any morphological change and showed no cytotoxicity.