Coniferyl alcohol, sinapyl alcohol and scopoletin in tobacco callus tissue during growth of a subculture

Abstract

Coniferyl and sinapyl alcohols were isolated, identified and quantitatively determined as unbound (or weakly bound) phenylpropanoids in neutral hot‐water extracts of Nicotiana tabacum L. callus tissue. This is the first identification of these alcohols in cultured tobacco callus. Scopoletin was also detected in these extracts, and it was the most abundant of these three phenylpropanoids with concentrations that ranged from 50–119 μg/g dry wt. Coniferyl alcohol (17–34 μg/g dry wt.) and sinapyl alcohol (23–35 μg/g dry wt.) were present in nearly equimolar concentration ratios and at levels which were about half those determined for unbound (or weakly bound) scopoletin. The amount of scopoletin extracted increased about 10 times when 1 M HCl‐50% methanol ‐ 0.3% ascorbic acid was used as the extractant. This indicated that most scopoletin moieties were strongly bound, perhaps by acid‐hydrolyzable linkage. Coniferyl alcohol and sinapyl alcohol were not found in the acid extracts, presumably because they were acid‐labile. In general, the concentration of each endogenous unbound (or weakly bound) phenylpropanoid appeared to remain relatively constant throughout the growth phase of the subculture. The only exceptions to this were the relatively higher concentrations of scopoletin and coniferyl alcohol present during the initial 0–2 weeks of subculture.