| 摘要 |
PROBLEM TO BE SOLVED: To obtain an antimicrobial agent that has excellent antimicrobial effect on bacteria, yeast and fungi, and is useful for foods, cosmetics and medicines by using, as effective components, particular compounds obtained from Job's tear malts by a specific treatment. SOLUTION: This antimicrobial agent comprises a naphthoquinone derivative shown by the formula. The naphthoquinone derivative of the formula is obtained by producing Job's tear malts by dark culture, triturating, freeze-drying or smashing the malts, subjecting the triturated, freeze-dried or smashed malts to extraction using a lower alcohol such as methyl or ethyl alcohol, and the extract to liquid-liquid partition extraction to obtain simple lipid which is soluble freely to acetone, and finally isolating the naphthoquinone derivative through repeated chromatographyic partition. The isolated naphthoquinone derivative is added to foods, beverages and cosmetics, or applied to packaging containers for them directly or in the form of a solution, dispersion, or emulsion. |
