Global warming has led to frequent droughts, posing challenges for afforestation in arid and semiarid regions. In search of labor-saving and money-saving methods to improve the survival and growth rates of trees in these regions, we isolated and identified fungal endophytes that can potentially enhance the drought-resistance abilities of seedlings. We isolated 93 endophytic strains from the roots of Pinus tabulaeformis trees grown on an arid cliff. Three isolates increased the drought resistance of the tree seedlings. Using morphological, molecular, and physiological-biochemical methods, we identified three isolates as different clones of a strain of Phoma spp. and studied the strain’s effect on stress resistance-related substances in the seedlings. The results showed that the strain improved drought tolerance and increased the seedlings’ proline levels and antioxidant enzyme activities. The strain also secreted abundant extracellular abscisic acid, which likely triggered the seedlings’ protective mechanisms. This endophytic strain may provide a cheaper labor-saving, sustainable alternative to traditional methods of enhancing drought resistance.
Background: Agarwood is a highly sought-after resinous wood for uses in medicine, incense, and perfume production. To overcome challenges associated with agarwood production in Aquilaria sinensis, several artificial agarwood-induction treatments have been developed. However, the effects of these techniques on the metabolome of the treated wood samples are unknown. Therefore, the present study was conducted to evaluate the effects of four treatments: fire drill treatment (F), fire drill + brine treatment (FS), cold drill treatment (D) and cold drill + brine treatment (DS)) on ethanol-extracted oil content and metabolome profiles of treated wood samples from A. sinensis. Results: The ethanol-extracted oil content obtained from the four treatments differed significantly (F < D < DS < FS). A total of 712 metabolites composed mostly of alkaloids, amino acids and derivatives, flavonoids, lipids, phenolic acids, organic acids, nucleotides and derivatives, and terpenoids were detected. In pairwise comparisons, 302, 155, 271 and 363 differentially accumulated metabolites (DAM) were detected in F_vs_FS, D_vs_DS, F_vs_D and FS_vs_DS, respectively. The DAMs were enriched in flavonoid/flavone and flavonol biosynthesis, sesquiterpenoid and triterpenoid biosynthesis. Generally, addition of brine to either fire or cold drill treatments reduced the abundance of most of the metabolites. Conclusion: The results from this study offer valuable insights into synthetically-induced agarwood production in A. sinensis.
Microbial fermentation has been widely used to improve the quality and functional composition of food and edibles; however, the approach has rarely been applied to traditional Chinese medicines. In this study, to understand the effect of microbial fermentation on the active ingredients of traditional Chinese medicines, we used Bifidobacterium bifidum and Bacillus subtilis to ferment the traditional Chinese medicine, Cornus officinalis fruit (COF), and determined the levels of active ingredients using HPLC (high-performance liquid chromatography). According to the results, both B. subtilis and B. bifidum substantially increased the amount of gallic acid in the COF culture broth after fermentation; however, the two species of bacteria had no effect on the loganin content. Moreover, the B. subtilis fermentation reduced the contents of ursolic acid and oleanolic acid in the COF broth, whereas the B. bifidum fermentation did not. This study contributes to a better understanding of the mechanism by which microbial fermentation alters the active ingredient levels of traditional Chinese medicines, and suggests that fermentation may potentially improve their functional ingredients.