RESUMEN
Further investigation of secondary metabolites of a marine-alga-derived fungus Aspergillus sp. RR-YLW-12 led to isolate one new ophiobolin-type sesterterpenoid (1), four new drimane-type sesquiterpenoids (2-5) and one natural occurring compound (6), together with seven known compounds (7-13). Their structures and stereochemistry were elucidated by extensive spectroscopic analysis of NMR and HRMS experiments, and by comparison with the literature data. All isolates were evaluated for growth inhibition of five marine harmful microalgae. The new compounds exhibited significant to moderate inhibitory effects towards all tested microalgae species with IC50 values ranging from 5.8 to 54.5 µg/mL.
Asunto(s)
Sesquiterpenos , Estructura Molecular , Aspergillus/química , Hongos , Espectroscopía de Resonancia MagnéticaRESUMEN
Six new sesquiterpenoids including three bisabolane derivatives, trichobisabolins O1, O2, and P (1-3), two nerolidol derivatives, trichonerolins A and B (4 and 5), one acorane, trichoacorin A (6), along with one new steroid, isoergokonin B (7), were isolated from the culture of Trichoderma brevicompactum A-DL-9-2 obtained from the inner tissue of the red alga Chondria tenuissima. Their structures and relative configurations were assigned by interpretation of 1D/2D NMR and MS data. As acyclic sesquiterpenoids, compounds 4 and 5 were discovered from Trichoderma for the first time. Compounds 1-7 were evaluated for the inhibition of some marine-derived organisms, in which, 3 and 4/5 exhibited potent inhibition against Amphidinium carterae and Chattonella marina with IC50 of 1.8 µg/mL and 1.2 µg/mL, respectively. In addition, compound 7 could inhibit the growth of Pseudoalteromonas citrea with an MIC value of 64 µg/mL.
Asunto(s)
Antiinfecciosos/farmacología , Productos Biológicos/farmacología , Fitoplancton/efectos de los fármacos , Rhodophyta/microbiología , Sesquiterpenos/farmacología , Trichoderma/química , Antiinfecciosos/aislamiento & purificación , Productos Biológicos/aislamiento & purificación , Hypocreales , Estructura Molecular , Pseudoalteromonas/efectos de los fármacos , Sesquiterpenos/aislamiento & purificaciónRESUMEN
An examination of the endophytic fungus Trichoderma asperellum A-YMD-9-2 obtained from the marine red alga Gracilaria verrucosa led to the isolation of seven new chromanoid norbisabolane derivatives, trichobisabolins I-L (1-4) and trichaspsides C-E (5-7). Their structures and relative configurations were established on the basis of spectroscopic techniques, mainly including 1D/2D NMR and MS, and the absolute configuration of 1 was assigned by X-ray crystallographic analysis using Cu Kα radiation. All of these isolates feature a 1,9-epoxy ring system, and 5-7 represent the second occurrence of norbisabolane aminoglycosides. Compounds 1-7 exhibited potent inhibition of several marine phytoplankton species.
Asunto(s)
Aminoglicósidos/farmacología , Cromanos/farmacología , Gracilaria/microbiología , Trichoderma/química , Aminoglicósidos/química , Aminoglicósidos/aislamiento & purificación , Cromanos/aislamiento & purificación , Cristalografía por Rayos X , Endófitos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Trichoderma/fisiologíaRESUMEN
Eight new bisabolane derivatives, trichobisabolins A-H, along with two known ones, (3R,6R,7R)-1,10-bisaboladien-3-ol (9) and (3R,6R,7S)-1,10-bisaboladien-3,6-diol (10) were isolated from the culture of Trichoderma asperellum Y6-2, obtained from the surface of the marine red alga Chondrus ocellatus. Their structures and relative configurations were identified by interpretation of 1D/2D NMR and MS data. Compounds 1-8 were assayed for inhibiting the growth of some marine-derived organisms, including four marine phytoplankton species, one marine zooplankton species, and five pathogenic bacteria. All of them exhibited inhibition against the marine phytoplanktons with IC50 values ranging from 2.1-78⯵g/mL, compounds 4 and 8 showed weak lethality to the marine zooplankton, and none of them had inhibition against the five pathogenic bacteria.
Asunto(s)
Bacterias/efectos de los fármacos , Chondrus/microbiología , Ciclohexanos/farmacología , Fitoplancton/efectos de los fármacos , Trichoderma/química , China , Ciclohexanos/aislamiento & purificación , Estructura Molecular , Relación Estructura-ActividadRESUMEN
Three cyclonerane sesquiterpenoids, including the known cyclonerodiol (1), together with its new derivatives, (10E)-12-acetoxy-10-cycloneren-3,7 -diol (2) and 12-acetoxycycloneran-3,7-diol (3) were isolated from the cultures of marine-sediment-derived fungus Trichoderma harzianum P1-4. The structures of the new compounds (2 and 3) were elucidated based on extensive spectroscopic methods (1D/2D NMR and HR-MS) and optical rotation analysis.
Asunto(s)
Sesquiterpenos/química , Trichoderma/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Sedimentos Geológicos/microbiología , Espectroscopía de Resonancia Magnética/métodos , Estructura Molecular , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Staphylococcus aureus/efectos de los fármacosRESUMEN
A new sesquiterpene, albican-1,14-diol (1), and seven known compounds, including sterigmatocystin (2), 3-hydroxy-5-(hydroxymethyl)-4-(4'-hydroxyphenoxy) pyrrolidin-2-one (3), (1H-indol-3-yl) oxoacetamide (4), indole-3-carboxylic acid (5), indole-3-acetic acid (6), indole-3-carboxaldehyde (7), and volemolide (8), were isolated from the cultures of Aspergillus versicolor, an endophytic fungus isolated from the marine green alga Codium fragile. The structure of 1 was elucidated by 1D, 2D NMR and mass spectroscopic techniques. The bioassay results showed that 1 possessed potent activity against brine shrimp, Escherichia coli, and Staphyloccocus aureus.
Asunto(s)
Aspergillus/química , Sesquiterpenos/química , Sesquiterpenos/farmacología , Animales , Artemia/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Staphylococcus aureus/efectos de los fármacosRESUMEN
Four new chamigrane derivatives, laurecomin A (1), laurecomin B (2), laurecomin C (3), and laurecomin D (4), one new naturally occurring sesquiterpene, 2,10-dibromo-3-chloro-7-chamigren-9-ol acetate (5), and three known halogenated structures, deoxyprepacifenol (6), 1-bromoselin-4(14),11-diene (7), and 9-bromoselin-4(14),11-diene (8), were isolated from the marine red alga Laurencia composita collected from Pingtan Island, China. The structures of these compounds were unambiguously established by 1D, 2D NMR and mass spectroscopic techniques. The bioassay results showed that 2 was active against both brine shrimp and fungus Colletotrichum lagenarium.