The enzyme from Zea mays, variety Delprim, gives mainly sesquithujene with (S)-beta-bisabolene and (E)-beta-farnesene plus traces of other sesquiterpenoids, cf. EC 4.2.3.55 [(S)-beta-bisabolene synthase] and EC 4.2.3.47 (beta-farnesene synthase). It requires Mg2+ or Mn2+. The exact product ratio is dependent on which metal ion is present.
The variability of sesquiterpenes emitted from two Zea mays cultivars is controlled by allelic variation of two terpene synthase genes encoding stereoselective multiple product enzymes.