title: Selected phytotoxins and organic extracts from endophytic fungus Edenia gomezpompae as light reaction of photosynthesis inhibitors.
abstract: In a search for natural herbicides, we investigated the action mechanism of the naphthoquinone spiroketals, isolated from the endophytic fungus Edenia gomezpompae: preussomerins EG1 (1) and EG4 (2), and palmarumycins CP17 (3), and CP2 (4) on the photosynthesis light reactions. The naphthoquinone spiroketals 1-4 inhibited the ATP synthesis in freshly lysed spinach thylakoids from water to MV, and they also inhibited the non-cyclic electron transport in the basal, phosphorylating and uncoupled conditions from water to MV. Therefore, they act as Hill reaction inhibitors. The results suggested that naphthoquinone spiroketals 1-4 have two interactions and inhibition site on the PSII electron transport chain. The first one involves the water splitting enzyme inhibition; and, the second on the acceptor site of PSII in a similar way that herbicide Diuron, studied by polaroghaphy and corroborated by fluorescence of the chlorophyll a of PSII. The culture medium and mycelium organic extracts from four morphological variants of E. gomezpompae were phytotoxic, and the culture medium extracts were more potent than mycelium extracts. They also act as Hill reaction inhibitors.
authors.affiliation: Instituto de Química, Departamento de Productos Naturales, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Coyoacán, México D.F. 04510, Mexico. Electronic address: mlmacias@unam.mx.
authors.forename: Martha Lydia
authors.initials: ML
authors.lastname: Macías-Rubalcava
authors.affiliation: Instituto de Química, Departamento de Productos Naturales, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Coyoacán, México D.F. 04510, Mexico.
authors.forename: María Emma
authors.initials: ME
authors.lastname: Ruiz-Velasco Sobrino
authors.affiliation: Instituto de Química, Departamento de Productos Naturales, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Coyoacán, México D.F. 04510, Mexico.
authors.forename: Claudio
authors.initials: C
authors.lastname: Meléndez-González
authors.affiliation: Facultad de Química, Departamento de Bioquímica, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Coyoacán, México D.F. 04510, Mexico.
authors.forename: Beatriz
authors.initials: B
authors.lastname: King-Díaz
authors.affiliation: Facultad de Química, Departamento de Bioquímica, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Coyoacán, México D.F. 04510, Mexico.
authors.forename: Blas
authors.initials: B
authors.lastname: Lotina-Hennsen
mesh_terms: D001203:Ascomycota / Q000737:chemistry / Q000378:metabolism*; D002734:Chlorophyll / Q000737:chemistry; D000077194:Chlorophyll A; D004237:Diuron / Q000633:toxicity; D004579:Electron Transport / Q000187:drug effects / Q000528:radiation effects; D004852:Epoxy Compounds / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005663:Furans / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D006540:Herbicides / Q000633:toxicity; D006576:Heterocyclic Compounds, 4 or More Rings / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D008027:Light; D025282:Mycelium / Q000737:chemistry / Q000378:metabolism; D009285:Naphthoquinones / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry; D010788:Photosynthesis / Q000187:drug effects*; D045332:Photosystem II Protein Complex / Q000037:antagonists & inhibitors / Q000378:metabolism; D018724:Spinacia oleracea / Q000378:metabolism; D013141:Spiro Compounds / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D020524:Thylakoids / Q000378:metabolism
chemical_list: D004852:Epoxy Compounds; D005663:Furans; D006540:Herbicides; D006576:Heterocyclic Compounds, 4 or More Rings; D009285:Naphthoquinones; D009930:Organic Chemicals; D045332:Photosystem II Protein Complex; D013141:Spiro Compounds; C530526:preussomerin EG1; C520774:spiroketal; D002734:Chlorophyll; D004237:Diuron; D000077194:Chlorophyll A
keywords: Edenia gomezpompae; Endophytic fungi; Hill reaction inhibitors; Naphthoquinone spiroketals; Palmarumycins; Photosynthetic activities; Phytotoxic compounds; Preussomerins