In order to search for anti -melanin formation agents from Korean medicinal herbs, we selected 21 Korean medicinal herbs, based on a review of Korean traditional medicine books and the recommendations of Korean traditional medical doctors. We tested for i

Irradiated and non-irradiated Korean medicinal herbs were extracted by water and 70% ethanol. Antimicrobial activity of these extracts were investigated against selected food hygiene microoganisms. The ethanol extracts of the non-irradiated Agrimonia pilosa ledebour japonica Nakai, Curcuma longa Linne and Angelica gigas Nakai were completely inhibited on four species of bacteria, such as Vibrio parahaemolyticus, Clostridium perfringenes, Bacillus subtilis and Staphylococcus aureus. Also, above four strains did not have antibacterial activity in the water-ethanol mixtures. Futhermore, the ethanol extracts of the non-irradiated Agrimonia pilosa ledebour Japonica Nakai, Curcuma ledoaria Roscoe, Curcuma longa Linne and Scutellaria baikalensis George were shown inhibitory effects against Aspergillus flavus and Penicillium islandicum. And the water extract of Scutellaria baikalensis George was the same effect to these molds. Essentially the same results were observed when samples irradiated at a dose of 10 kGy.

Korean medicinal herb extracts(KMHE) were applied to the preservation of greenhouse produce in order to prove their effectiveness. KMHE showed remarkable antimicrobial effects against Bacillus cereus, Peudomonas syringae, and Corynebacterium xerosis causing the postharvest decay of greenhouse produce. Among KMHE the extracts of Rheum palmatum L. and Coptis chinensis Franch most obviously inhibited the growth of microorganims causing the Postharvest decay of greenhouse produce, which destroyed to undetectable levels when treated with more than 500ppm of KMHE. The activities of KMHE were stable in the wide spectrum of pH and temperature. Direct visualization of microbial cells by using both transmission electron microscope and scanning electron microscope showed microbial cell membrane the function of which was destroyed by treating with the dilute solutions of KMHE. This change of cellular membrane permeability could be identified in the experiment that O-nitrophenyl--D-galactopyranoside(ONPG), the artificial substrate of -galactosidase, was hydrolyzed in the presence of KMHE, indicating that the membrane was perturbed by KMHE.