@article{ShadyElHossaryFouadetal.2017,
  author    = {Shady, Nourhan Hisham and El-Hossary, Ebaa M. and Fouad, Mostafa A. and Gulder, Tobias A. M. and Kamel, Mohamed Salah and Abdelmohsen, Usama Ramadan},
  title     = {Bioactive natural products of marine sponges from the Genus Hyrtios},
  series = {Molecules},
  volume    = {22},
  journal   = {Molecules},
  number    = {5},
  doi       = {10.3390/molecules22050781},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158227},
  pages     = {781},
  year      = {2017},
  abstract  = {Marine sponges are known as a rich source for novel bioactive compounds with valuable pharmacological potential. One of the most predominant sponge genera is Hyrtios, reported to have various species such as Hyrtios erectus, Hyrtios reticulatus, Hyrtios gumminae, Hyrtios communis, and Hyrtios tubulatus and a number of undescribed species. Members of the genus Hyrtios are a rich source of natural products with diverse and valuable biological activities, represented by different chemical classes including alkaloids, sesterterpenes and sesquiterpenes. This review covers the literature until June 2016, providing a complete survey of all compounds isolated from the genus Hyrtios with their corresponding biological activities whenever applicable.},
  language  = {en}
}
@article{RoedelBredeHirschfeldetal.2013,
  author    = {R{\"o}del, Mark-Oliver and Brede, Christian and Hirschfeld, Mareike and Schmitt, Thomas and Favreau, Philippe and St{\"o}cklin, Reto and Wunder, Cora and Mebs, Dietrich},
  title     = {Chemical Camouflage - A Frog's Strategy to Co-Exist with Aggressive Ants},
  series = {PLOS ONE},
  volume    = {8},
  journal   = {PLOS ONE},
  number    = {12},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0081950},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128181},
  pages     = {e81950},
  year      = {2013},
  abstract  = {Whereas interspecific associations receive considerable attention in evolutionary, behavioural and ecological literature, the proximate bases for these associations are usually unknown. This in particular applies to associations between vertebrates with invertebrates. The West-African savanna frog Phrynomantis microps lives in the underground nest of ponerine ants (Paltothyreus tarsatus). The ants usually react highly aggressively when disturbed by fiercely stinging, but the frog is not attacked and lives unharmed among the ants. Herein we examined the proximate mechanisms for this unusual association. Experiments with termites and mealworms covered with the skin secretion of the frog revealed that specific chemical compounds seem to prevent the ants from stinging. By HPLC-fractionation of an aqueous solution of the frogs' skin secretion, two peptides of 1,029 and 1,143 Da were isolated and found to inhibit the aggressive behaviour of the ants. By de novo sequencing using tandem mass spectrometry, the amino acid sequence of both peptides consisting of a chain of 9 and 11 residues, respectively, was elucidated. Both peptides were synthesized and tested, and exhibited the same inhibitory properties as the original frog secretions. These novel peptides most likely act as an appeasement allomone and may serve as models for taming insect aggression.},
  language  = {en}
}
@article{KraussVikukYoungetal.2020,
  author    = {Krauss, Jochen and Vikuk, Veronika and Young, Carolyn A. and Krischke, Markus and Mueller, Martin J. and Baerenfaller, Katja},
  title     = {Epichlo{\"e} endophyte infection rates and alkaloid content in commercially available grass seed mixtures in Europe},
  series = {Microorganisms},
  volume    = {8},
  journal   = {Microorganisms},
  number    = {4},
  issn      = {2076-2607},
  doi       = {10.3390/microorganisms8040498},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-203323},
  pages     = {498},
  year      = {2020},
  abstract  = {Fungal endophytes of the genus Epichlo{\"e} live symbiotically in cool season grass species and can produce alkaloids toxic to insects and vertebrates, yet reports of intoxication of grazing animals have been rare in Europe in contrast to overseas. However, due to the beneficial resistance traits observed in Epichlo{\"e} infected grasses, the inclusion of Epichlo{\"e} in seed mixtures might become increasingly advantageous. Despite the toxicity of fungal alkaloids, European seed mixtures are rarely tested for Epichlo{\"e} infection and their infection status is unknown for consumers. In this study, we tested 24 commercially available seed mixtures for their infection rates with Epichlo{\"e} endophytes and measured the concentrations of the alkaloids ergovaline, lolitrem B, paxilline, and peramine. We detected Epichlo{\"e} infections in six seed mixtures, and four contained vertebrate and insect toxic alkaloids typical for Epichlo{\"e} festucae var. lolii infecting Lolium perenne. As Epichlo{\"e} infected seed mixtures can harm livestock, when infected grasses become dominant in the seeded grasslands, we recommend seed producers to test and communicate Epichlo{\"e} infection status or avoiding Epichlo{\"e} infected seed mixtures.},
  language  = {en}
}
@article{FayezFeineisMudogoetal.2017,
  author    = {Fayez, Shaimaa and Feineis, Doris and Mudogo, Virima and Awale, Suresh and Bringmann, Gerhard},
  title     = {Ancistrolikokines E-H and related 5,8\('\)-coupled naphthylisoquinoline alkaloids from the Congolese liana \(Ancistrocladus\) \(likoko\) with antiausterity activities against PANC-1 human pancreatic cancer cells},
  series = {RSC Advances},
  volume    = {7},
  journal   = {RSC Advances},
  number    = {85},
  doi       = {10.1039/c7ra11200a},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-172008},
  pages     = {53740-53751},
  year      = {2017},
  abstract  = {A striking feature of the metabolite profile of \(Ancistrocladus\) \(likoko\) (Ancistrocladaceae) is the exclusive production of 5,8\('\)-linked naphthylisoquinoline alkaloids varying in their OMe/OH substitution patterns and in the hydrogenation degree in their isoquinoline portions. Here we present nine new compounds of this coupling type isolated from the twigs of this remarkable Central African liana. Three of them, the ancistrolikokines E (9), E\(_2\) (10), and F (11), are the first 5,8\('\)-linked naphthyldihydroisoquinolines found in nature with \(R\)-configuration at C-3. The fourth new metabolite, ancistrolikokine G (12), is so far the only representative of the 5,8\('\)-coupling type that belongs to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Moreover, five new \(N\)-methylated naphthyltetrahydroisoquinolines, named ancistrolikokines A\(_2\) (13), A\(_3\) (14), C\(_2\) (5), H (15), and H\(_2\) (16) are presented, along with six known 5,8\('\)-linked alkaloids, previously identified in related African \(Ancistrocladus\) species, now found for the first time in \(A.\) \(likoko\). The structural elucidation was achieved by spectroscopic analysis (HRESIMS, 1D and 2D NMR) and by chemical (oxidative degradation) and chiroptical (electronic circular dichroism) methods. The new ancistrolikokines showed moderate to good preferential cytotoxic activities towards pancreatic PANC-1 cells in nutrient-deprived medium (NDM), without causing toxicity under normal, nutrient-rich conditions, with ancistrolikokine H\(_2\) (16) being the most potent compound.},
  language  = {en}
}