[Objective] To examine the effect of endophytic fungi ALl2 (Gilmaniella sp.) on metabolites distribution in organs of Atractylodes lancea. [Method] Endophytic fungi ALl2 was inoculated on Atraetylodes lancea plantlets in tissue culture, and the distribution of cellulose, hemicellulose, lignin, soluble sugar in leaves and roots of the inoculated group were detected. The weight of leaves and roots were compared. Gas Chromatography was used to analyze the volatile oil components. [Result] Compared with the control group, the average fresh weight and dry weight of leaves and roots of A. lancea which had been symbiosed with ALl2 increased significantly. The content of lignin and soluble sugar increased in the leaves of the inoculated group, and the content of cellulose, hemicellulose, lignin, soluble sugar and volatile oil also increased in roots. [Conclusion] The results indicate that symbiosed with ALl2 is benefit for the development of A. lancea roots and can promote the transfer and accumulation of the medicinal components to the roots.
Fungal endophytes have been isolated from almost every plant, infecting their hosts without causing visible disease symptoms, and yet have still proved to be involved in plant secondary metabolites accumulation. To decipher the possible physiological mechanisms of the endophytic fungus-host interaction, the role of protein phosphorylation and the relationship between endophytic fungus-induced kinase activity and nitric oxide (NO) and brassinolide (BL) in endophyte-enhanced volatile oil accumulation in Atractylodes lancea plantlets were investigated using pharmacological and biochemical approaches. Inoculation with the endophytic fungus Gilmaniella sp. ALl2 enhanced the activities of total protein phosphorylation, Ca2^-dependent protein kinase, and volatile oil accumulation in A. lancea plantlets. The upregulation of protein kinase activity could be blocked by the BL inhibitor brassinazole. Furthermore, pretreatments with the NO-specific scavenger cPTIO significantly reduced the increased activities of protein kinases in A. lancea plantlets inoculated with endophytic fungus. Pretreatments with different protein kinase inhibitors also reduced fungus-induced NO production and volatile oil accumulation, but had barely no effect on the BL level. These data suggest that protein phosphorylation is required for endophyte- induced volatile oil production in A. lancea plantlets, and that crosstalk between protein phosphorylation and the NO pathway may occur and act as a downstream signaling event of the BL pathway.
[Objective] This study was to explore the effect of three precursors on the accumulation of principal volatile oil constituents in tissue culture plantlets of Atractylodes lancea (Thunb.) DC. with the aim to provide references for the improvement of artificial cultivated A. lancea quality. [Method] Three precursors were added into the MS rooting medium for A. lancea tissue culture plantlets and the volatile oil was extracted by ultrasonication after cultured for several days. The content of atractylon, atractylol, β-eucalyptol and atractydin in the volatile oil were determined by using gas chromatography method. [Result] The addition of xylose, isoprene and tetrahydrofuran impacted the growth indicators, yield of volatile oil and relative percentage content of the four constituents of A. lancea tissue culture plantlets. In the 6 g/L xylose optimized medium, the atractylon and β-eucalyptol content reached up to 4.23% and 56.34%, respectively, 1.41% and 1.66% higher than the control; although the addition of isoprene into medium raised the atractylon content, the accumulation of total volatile oil was inhibited that it decreased by 23.67%, 31.06% and 7.10% to the control; for the tetrahydrofuran optimized medium, the content of atractylon, atractylol and atractydin all increased, and the total volatile oil content increased by 49.97% to the control when the concentration of tetrahydrofuran was 0.07 g/L. [Conclusion] The addition of xylose and tetrahydrofuran promoted the accumulation of principal constituents of the volatile oil, whereas the addition of isoprene inhibited the accumulation.