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A wide range of external stress stimuli trigger plant cells to undergo complex network of reactions that ultimately lead to the synthesis and accumulation of secondary metabolites. Accumulation of such metabolites often occurs in plants subjected to stresses including various elicitors or signal molecules. Throughout evolution, endophytic fungi, an important constituent in the environment of medicinal plants, have known to form long-term stable and mutually beneficial symbiosis with medicinal plants. The endophytic fungal elicitor can rapidly and specifically induce the expression of specific genes in medicinal plants which can result in the activation of a series of specific secondary metabolic pathways resulting in the significant accumulation of active ingredients. Here we summarize the progress made on the mechanisms of fungal elicitor including elicitor signal recognition, signal transduction, gene expression and activation of the key enzymes and its application. This review provides guidance on studies which may be conducted to promote the efficient synthesis and accumulation of active ingredients by the endogenous fungal elicitor in medicinal plant cells, and provides new ideas and methods of studying the regulation of secondary metabolism in medicinal plants. [ABSTRACT FROM AUTHOR]

In this study, the isolation of an endophytic fungus from the leaves of the medicinal herb adlay ( Coix lacryma- jobi L. var. ma- yuen Stapf) is reported for the first time. The fungus produced Triolein (trioleoylglycerol), a major constituent of triacylglycerols (TAGs) of adlay, in rice medium under shake-flask and bench-scale fermentation conditions. The fungus was identified as Gibberella moniliformis ( Fusarium verticillioides) by its morphology and authenticated by ITS analysis (ITS1 and ITS2 regions and the intervening 5.8S rDNA region). Triolein was identified by HPLC-ELSD coupled with APCI-MS and confirmed through comparison with authentic standard. The concentration of triolein produced by G. moniliformis AH13 reached 2.536 ± 0.006 mg/g dry weight of mycelium. Moreover, the EtOAc extract of G. moniliformis AH13 showed strong antitumor activity against four types of tumor cells (A549, HCT116, MDA-MB-231, and SW1990). These results suggest that G. moniliformis AH13 in adlay has significant scientific and industrial potential to meet the pharmaceutical demands and sustainable energy requirements for TAGs in a cost-effective, easily accessible, and reproducible way and is also a potential novel source of natural antitumor bioactive agents. [ABSTRACT FROM AUTHOR]

Context: Endophytic fungi are microorganisms living within the tissues of host plants, and have proven to be rich sources of biologically active secondary metabolites and therefore have attracted increasing attention in recent years. Objective: To isolate and characterize bioactive constituents from the endophytic fungus cultures of Crocus sativus Linn. (Iridaceae). Materials and methods: Endophytes were isolated from the corm of C. sativus. Endophytic fungus cultures were subjected to repeated column chromatography. Chemical structure was elucidated based on extensive spectroscopic methods and X-ray diffraction analysis. Several pathogenic fungi isolates and tumor cell lines were employed to evaluate the antifungal and cytotoxic activities of the isolated compound. Results: An isolate of Penicillium vinaceum (strain no. X17) was obtained from the corm of C. sativus. Chemical investigations of the endophyte culture broth afforded an unique quinazoline alkaloid (1), identified as (-)-(1R,4R)- 1,4-(2,3)-indolmethane-1-methyl-2,4-dihydro-1H-pyrazino-[2,1-b]-quinazoline-3,6-dione, which showed cytotoxic (IC50 range 40.55–76.83μg/mL) and antifungal (MIC80 range 16–64μg/mL) activities. Discussion and conclusions: Endophytes in C. sativus can be a rich source of novel bioactive compounds, which prompts us to expand the medicinal resource of this valuable plant in another way. Compound 1 exhibited potential cytotoxic and antifungal activities and may be considered a lead compound for promising antifungal and anticariogenic agent. [ABSTRACT FROM AUTHOR]

Trichoderma atroviride develops a symbiont relationship with Salvia miltiorrhiza and this association involves a number of signaling pathways and proteomic responses between both partners. In our previous study, we have reported that polysaccharide fraction (PSF) of T. atroviride could promote tanshinones accumulation in S. miltiorrhiza hairy roots. Consequently, the present data elucidates the broad proteomics changes under treatment of PSF. Furthermore, we reported several previously undescribed and unexpected responses, containing gene expression patterns consistent with biochemical stresses and metabolic patterns inside the host. In summary, the PSF-induced tanshinones accumulation in S. miltiorrhiza hairy roots may be closely related to Ca2+ triggering, peroxide reaction, protein phosphorylation, and jasmonic acid (JA) signal transduction, leading to an increase in leucine-rich repeat (LRR) protein synthesis. This results in the changes in basic metabolic flux of sugars, amino acids, and protein synthesis, along with signal defense reactions. The results reported here increase our understanding of the interaction between T. atroviride and S. miltiorrhiza and specifically confirm the proteomic responses underlying the activities of PSF. [ABSTRACT FROM AUTHOR]

The article focuses on a study conducted by the authors related to the endophytic fungus Xylaria sp.'s chemical compounds. It states that the fungus was isolated from the liverwort scapania verrucosa. It mentions that the filtrate which was extracted with ethyl acetate was subjected to different types of chromatography. It highlights that compounds found in the fungus were paecilospire, methyl curvulinate and curvulin.