To provide a substance that promotes the expression of a hyaluronic acid synthase gene in an effective manner and is able to be used in a wide range of applications. The promoter for the expression of a hyaluronic acid synthase gene has at least one active ingredient selected from the group consisting of: beta-caryophyllene, caryophellene oxide, and a compound having the following structural formula. (X is CH3, NH2, or NHCH3.)本發明之課題在於提供一種可活用於廣泛用途中且有效地促進玻尿酸合成酵素基因表現之物質。本發明之玻尿酸合成酵素基因表現促進劑以選自由β-石竹烯、石竹烯氧化物及具有下述結構式之化合物所組成之群中之一種以上作為有效成分。(X為CH3、NH2或NHCH3)
