麴 (kiku, “malt”) + 菌 (kin, “fungus”)
麹菌 (hiragana きくきん, rōmaji kikukin)
麴 (kōji, “malt”) + 菌 (kin, “fungus”)
麹菌 (hiragana こうじきん, rōmaji kōjikin, historical hiragana かうじきん)