Biosynthesis of tropolones from callus and suspension-cultured cells initiated from young seedlings of Thuja plicata Donn

Thuja plicata callus and cell cultures have been cultured in Gamborg B5 medium supplemented with saccharose or glucose, 1-naphtalene acetic acid (NAA) and benzylaminopurine (BAP) as growth regulators. The addition of elicitor as yeast extract to callus culture of Thuja plicata leads to an increase in the production of tropolones, typical heartwood constituents of Cupressus species. Calli cultured in a medium supplemented with saccharose 2% and yeast extract accumulate tropolones in about 6.5 mg g(-1) cell fresh weight, which is easily extracted from callus culture with ethylacetate. Without elicitation, the content of tropolones was only 1.75 mg g(-1) cell fresh weight. In a medium supplemented with glucose, the content of tropolone increases (8.1 mg with elicitation and 3.15 mg without elicitation). Cell cultures obtained from calli show an effect of the rotary shaker speed on the tropolones production (5.1 mg g(-1) at 120 rpm agitation and only 2 mg at 80 or 180 rpm).