The present invention relates to a Java ginger extract which is prepared from Java ginger as a starting material and aimed at a concentrate as an objective (concentrate including solid matter) obtained from a solute. The starting material or the products on any of the steps in which the objective is manufactured from the starting material is heated or exposed to sunlight. In relation to a peak area ratio on high-performance liquid chromatography (HPLC), the peak area ratio (D/M ratio) of a phenyl butenoid dimer represented by the following formula (1) to a monomer represented by the following formula (2) is 0.6 or higher. An intake/dose of the Java ginger extract can be decreased by increasing a content of a phenyl butenoid dimer with an NGF-like action.
