A Novosphingobium Strain Capable of Degrading Cembratriene-4,6-diol and Producing Aroma: Isolation, Identification and Biological Characterization

Abstract

To obtain strains capable of efficient cembratriene-4,6-diol (CBT-diol) degradation for enhancing the tobacco aroma quality, a target strain designated as Z1-1 was isolated from tobacco leaves utilizing CBT-diol as the primary carbon source. Based on morphological characteristics, physiological biochemistry, and 16S rRNA gene sequence analysis, the strain was preliminarily identified as Novosphingobium sp. Through single-factor and response surface methodology experiments, the optimal degradation conditions were determined to be 30 ℃, 150 r/min shaking speed, 4% inoculum size, and pH 7.0. Under these optimized conditions, a CBT-diol degradation efficiency of 83.47% was achieved within 36 h. The application of this strain in tobacco concentrate significantly increased the relative contents of several key aroma components. The relative contents of solanone, 9-hydroxy-4,7-megastigmatrienone, 4-hydroxy-β-damascone, and phytol increased to 7.22, 3.65, 1.79, and 3.80 times their original levels, respectively. These findings demonstrate that Novosphingobium sp. Z1-1 is an efficient CBT-diol-degrading and aroma-producing bacterium.

Keywords

cembratriene-4,6-diol / Novosphingobium sp. / phylogenetic analysis / isolation and identification / degradation

Funding

Open Project of the Key Laboratory of Cigarette Smoke, China National Tobacco Corporation(K2023-1-044P)