A new eremophilane-type sesquiterpene from the phytopatogen fungus Lasiodiplodia theobromae (Sphaeropsidaceae)

Abstract

O fungo fitopatogênico Lasiodiplodia theobromae, isolado de goiaba, foi cultivado em arroz por 32 dias à temperatura ambiente. Extração com CH 2 Cl 2 :MeOH (3:7), seguido de fracionamento cromatográfico do extrato forneceu o esteróide ergosterol. Da cultura fúngica em meio de Czapeck por 40 dias à temperatura ambiente, foram isolados a isocumarina cis-4-hidroximeleína e um sesquiterpeno do tipo eremofilano. O sesquiterpeno eremofilano está sendo descrito pela primeira vez na literatura. Este é o primeiro relato do isolamento de um sesquiterpeno eremofilano para o gênero Lasiodiplodia.The phytopatogenic fungus Lasiodiplodia theobromae, isolated from guava, was cultivated in rice for 32 days at room temperature. Extraction with CH 2 Cl 2 :MeOH (3:7), followed by chromatography fractionation of the extract provided ergosterol. From the fungus culture in Czapeck medium for 40 days at room temperature, were isolated isocoumarin cis-4-hydroxymeleine and an eremophilane-type sesquiterpene. The latter compound is being reported for the first time in the literature. Also, this is the first time that an eremophilane sesquiterpene is described for Lasiodiplodia genus.

Four New Chloro-Eremophilane Sesquiterpenes from an Antarctic Deep-Sea Derived Fungus, Penicillium sp. PR19N-1

“…The resonances of H-12 and H-14 were notably enhanced as a result of irradiating CH 3 -11, indicating that the axial-methyl at C-5, the equatorial-methyl at C-4, and the acetyl group at C-3 were co-facial. The coupling constants ( 3 J H-2, H-3 = 5.0 Hz; 3 J H-3, H-4 = 5.0 Hz ) in 1 similar with related data in known compounds that possessed the same partial structure [11,13] further confirmed the relative configuration at C-3 as β - orientation. The same relative configuration for CH 3 -11 and CH 3 -12 can also be inferred from a biogenetic pathway (Figure 3) involving the trans-conformation of the decalin unit of eremophilane sesquiterpenes and comparison with previously reported congeners [14,15,16].…”

Benzopyranones from the Endophytic Fungus Hyalodendriella sp. Ponipodef12 and Their Bioactivities

“…4-Hydroxymellein ( 2 ) has been isolated from many fungi such as Ascochyta sp. [ 16 ], Botryosphaeria mamane [ 17 ], Botryosphaeria obtusa [ 9 , 18 ], Botryosphaeria rhodina [ 19 ], Cercospora taiwanensis [ 20 ], Dinemasporium strigosum [ 21 ], Emericellopsis minima [ 22 ], Lasiodiplodia theobromae [ 23 ], Meliotus dentatus [ 24 ], Penicillium sp. [ 25 ], Seimatosporium sp.…”

Secondary Metabolites of Lasiodiplodia theobromae: Distribution, Chemical Diversity, Bioactivity, and Implications of Their Occurrence

“…Among the reported strains, the endophytic strain of G. mangostana produced the highest variability of melleins [ 41 ]. ( - )-Mellein is produced by most L. theobromae strains, while (3 R ,4 R )-4-hydroxymellein is the only mellein produced by a pathogenic strain of L. theobromae isolated from guava [ 37 ]. Tests were conducted to investigate the potato tuber formation, and melleins are among the inducing substances produced by L. theobormae [ 30 ].…”

“…L. theobromae #009, isolated from guava plants, when cultivated on rice produces ergosterol ( 113 ), while in liquid medium (i.e., Czapek), it produces cis -4-hydroxymellein and a new eremophilane-type sesquiterpene. This metabolite was spectroscopically characterized as 2,4,6-trimethyloct-2-enoic acid, 1,2,6,8a-tetrahydro-7-hydroxy-1,8a-dimethyl-6-oxo-2-naphtalenyl ester ( 114 ) [ 37 ]. Interestingly, 114 is related to botryosphaeridione ( 115 ), a new dihydronaphthalene-2,6-dione, which is produced in liquid culture by the strain PSU-M35 isolated from G. mandostana [ 41 ].…”