Chemical composition of volatile extract from Inula aschersoniana Janka var. aschersoniana growing in Bulgaria

The chemical composition of the volatile oil of Inula aschersoniana was studied by GC and GC-MS. Fortyfive constituents representing 92.9% of the total oil were detected. The oil contained fatty acids (55.2%) and alkanes (14.1%), followed by oxygenated monoterpenes (9.6%), sesquiterpenoids (7.1%) and aromatic compounds (4.5%). It is characterized by relatively low content of terpenoids in total 16.7% only of which linalool (2.1%) and t-cadinol (2.2%) were the dominant components in this class of compounds. Cluster analysis (CA) was used for determination of the relationship between the species in Inula verbascifolia aggregate

Dichomitus squalens partially tailors its molecular responses to the composition of solid wood

White-rot fungi, such as Dichomitus squalens, degrade all wood components and inhabit mixed-wood forests containing both soft- and hardwood species. In this study, we evaluated how D. squalens responded to the compositional differences in softwood [guaiacyl (G) lignin and higher mannan content] and hardwood [syringyl/guaiacyl (S/G) lignin and higher xylan content] using semi-natural solid cultures. Spruce (softwood) and birch (hardwood) sticks were degraded by D. squalens as measured by oxidation of the lignins using 2D-NMR. The fungal response as measured by transcriptomics, proteomics and enzyme activities showed a partial tailoring to wood composition. Mannanolytic transcripts and proteins were more abundant in spruce cultures, while a proportionally higher xylanolytic activity was detected in birch cultures. Both wood types induced manganese peroxidases to a much higher level than laccases, but higher transcript and protein levels of the manganese peroxidases were observed on the G-lignin rich spruce. Overall, the molecular responses demonstrated a stronger adaptation to the spruce rather than birch composition, possibly because D. squalens is mainly found degrading softwoods in nature, which supports the ability of the solid wood cultures to reflect the natural environment.Peer reviewe