Preparation and self-assembly of amphiphilic polylysine dendrons

Polylysine dendrons with lipid tails prepared by divergent solid-phase synthesis showed self-assembling properties in aqueous solutions.</p

Sesquiterpene lactone-containing extracts from two chicory cultivars show different anthelmintic activity in vitro against Ostertagia ostertagi

Mechanisms behind reported in vivo anthelmintic effects of chicory (Cichorium intybus) in ruminants are poorly understood but it is likely that plant compounds, like sesquiterpene lactones (SL), play a role. Objectives: The aim was to test the inhibitory activity of SL-containing extracts from two chicory cultivars on free-living and parasitic stages of Ostertagia ostertagi. Methods: Leaves from chicory cv. Spadona and cv. Puna II were freeze-dried and SL extracted with methanol/water. Resulting extracts were incubated with cellulase enzyme and SL were purified from other plant compounds by normal solid-phase extraction. Purified extracts were dissolved in DMSO. O. ostertagi eggs from a mono-infected calf were hatched and first-stage larvae (L1) were used in a larval feeding inhibition assay (LFIA), while L3 cultured from faeces were used in a larval exsheathment inhibition assay (LEIA). O. ostertagi adult worms recovered post-mortem were used for motility inhibition assays (AMIA) and worm motility was evaluated after 6, 24 and 48 h of incubation (37oC). In all in vitro assays, decreasing concentrations of chicory extracts in PBS (1% DMSO) were tested in triplicates with 1% DMSO in PBS as negative control. Chemical profile of the extracts was analysed by liquid chromatography (LC). Results: In the LFIA Spadona-extract inhibited larval feeding at significantly lower concentrations than Puna II-extract (EC50=31.5 [CI=25.9-38.3] g Spadona-extract/mL vs. EC50=121.1 [CI=95.2-153.8] g Puna II-extract/mL; p<0.0001). In the LEIA extracts from neither of the two cultivars interfered with the exsheathment of L3 at any of the tested concentrations. In the AMIA, Spadona-extract showed a significantly higher potency and exerted faster worm paralysis than Puna II-extract at all time points when tested at equal concentrations (p<0.0001). Preliminary LC analyses revealed different SL profiles of the extracts and further chemical characterization is undergoing. Discussion: The observed anthelmintic effects of SL-containing extracts from chicory seem to be stage-specific as L1 and adult O. ostertagi but not L3 were affected. Different anthelmintic potency of SL-containing extracts from different chicory cultivars may help the identification of the most active(s) compound(s) and of cultivars with higher antiparasitic potential

Antiparasitic activity of chicory (Cichorium intybus) and its natural bioactive compounds in livestock: a review

Increasing drug resistance in gastrointestinal (GI) parasites of livestock and concerns about chemical residues in animal products and the environment are driving the development of alternative control strategies that are less reliant on the use of synthetic drugs. An increasingly investigated approach is the use of bioactive forages with antiparasitic properties as part of the animal’s diet (nutraceuticals) or as potential sources of novel, natural parasiticides. Chicory (Cichorium intybus) is a multi-purpose crop and one of the most promising bioactive forages in temperate regions, and numerous in vivo trials have explored its potential against parasitic nematodes in livestock. However, it is unclear whether chicory can induce a direct and broad activity against various GI parasites in different livestock species, and the levels of chicory in the diet that are required to exert an efficient antiparasitic effect. Moreover, the mechanisms leading to the reported parasiticidal activity of chicory are still largely unknown, and its bioactive phytochemicals have only recently been investigated. In this review, we summarise the progress in the study of the antiparasitic activity of chicory and its natural bioactive compounds against GI parasites in livestock, through examination of the published literature. The available evidence indicates that feeding chicory can reduce faecal egg counts and/or worm burdens of abomasal nematodes, but not infections with intestinal worms, in ruminants. Highly chicory-rich diets (≥ 70% of chicory dry matter in the diet) may be necessary to directly affect abomasal parasitism. Chicory is known to synthesise several bioactive compounds with potential antiparasitic activity, but most research has been devoted to the role of sesquiterpene lactones (SL). Recent in vitro studies have confirmed direct and potent activity of SL-rich extracts from chicory against different GI helminths of livestock. Chicory SL have also been reported to exhibit antimalarial properties and its potential antiprotozoal activity in livestock remains to be evaluated. Furthermore, the detailed identification of the main antiparasitic metabolites of chicory and their pharmacokinetics need further confirmation. Research gaps and perspectives on the potential use of chicory as a nutraceutical forage and a source of bioactive compounds for parasite control in livestock are discussed

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