491-71-4Relevant articles and documents
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Farooq et al.
, p. 76 (1959)
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Kattaev,Nikonov
, (1973)
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Subramanian,Nagarajan
, p. 3312 (1971)
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The fungal leaf endophyte Paraconiothyrium variabile specifically metabolizes the host-plant metabolome for its own benefit
Tian, Yuan,Amand, Séverine,Buisson, Didier,Kunz, Caroline,Hachette, Fran?ois,Dupont, Jo?lle,Nay, Bastien,Prado, Soizic
, p. 95 - 101 (2014)
Fungal endophytes live inside plant tissues and some have been found to provide benefits to their host. Nevertheless, their ecological impact is not adequately understood. Considering the fact that endophytes are continuously interacting with their hosts, it is conceivable that both partners have substantial influence on each other's metabolic processes. In this context, we have investigated the action of the endophytic fungus Paraconiothyrium variabile, isolated from the leaves of Cephalotaxus harringtonia, on the secondary metabolome of the host-plant. The alteration of the leaf compounds by the fungus was monitored through metabolomic approaches followed by structural characterization of the altered products. Out of more than a thousand molecules present in the crude extract of the plant leaf, we have observed a specific biotransformation of glycosylated flavonoids by the endophyte. In all cases it led to the production of the corresponding aglycone via deglycosylation. The deglycosylated flavonoids turned out to display significant beneficial effects on the hyphal growth of germinated spores. Our finding, along with the known allelopathic role of flavonoids, illustrates the chemical cooperation underlying the mutualistic relationship between the plant and the endophyte.
Influence of Substrate Binding Residues on the Substrate Scope and Regioselectivity of a Plant O-Methyltransferase against Flavonoids
Tang, Qingyun,Vianney, Yoanes M.,Weisz, Klaus,Grathwol, Christoph W.,Link, Andreas,Bornscheuer, Uwe T.,Pavlidis, Ioannis V.
, p. 3721 - 3727 (2020/06/02)
Methylation of free hydroxyl groups is an important modification for flavonoids. It not only greatly increases absorption and oral bioavailability of flavonoids, but also brings new biological activities. Flavonoid methylation is usually achieved by a specific group of plant O-methyltransferases (OMTs) which typically exhibit high substrate specificity. Here we investigated the effect of several residues in the binding pocket of the Clarkia breweri isoeugenol OMT on the substrate scope and regioselectivity against flavonoids. The mutation T133M, identified as reported in our previous publication, increased the activity of the enzyme against several flavonoids, namely eriodictyol, naringenin, luteolin, quercetin and even the isoflavonoid genistein, while a reduced set of amino acids at positions 322 and 326 affected both, the activity and the regioselectivity of the methyltranferase. On the basis of this work, methylated flavonoids that are rare in nature were produced in high purity.
New Flavonoids from Artemisia frigida
Olennikov
, p. 623 - 627 (2020/07/27)
New flavonoids were isolated from the aerial part of Artemisia frigida Willd. (Asteraceae). Their structures were elucidated using UV, IR, and NMR spectroscopy and mass spectrometry as chrysoeriol-7-O-(2′′-Oacetyl)-β-D-glucopyranoside (2′′-O-acetylthermop
