Turmeric, obtained from the rhizomes of Curcuma longa, is used in South Asia as a traditional medicine for the treatment of epilepsy. To date, in vivo studies on the anticonvulsant activity of turmeric have focused on its principal curcuminoid, curcumin. However, poor absorption and rapid metabolism have limited the therapeutic application of curcumin in humans. To explore the therapeutic potential of turmeric for epilepsy further, we analyzed its anticonvulsant activity in a larval zebrafish seizure assay. Initial experiments revealed that the anticonvulsant activity of turmeric in zebrafish larvae cannot be explained solely by the effects of curcumin. Zebrafish bioassay-guided fractionation of turmeric identified bisabolene sesquiterpenoids as additional anticonvulsants that inhibit PTZ-induced seizures in both zebrafish and mice. Here, we present the first report of the anticonvulsant properties of bisabolene sesquiterpenoids and provide evidence which warrants further investigation toward the mechanistic understanding of their neuromodulatory activity.

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Summary The tropical Andes has a high density of glacial lakes that are situated in the high‐altitude páramo (3500–4500 m). Ecological information about such lakes is scant despite the fact that these lakes are an important source of water for drinking, irrigation and electricity generation and feed several major tributaries of the Amazon. In this study, we provide data on a survey of 31 lakes in Cajas National Park (Ecuador). Two of the lakes were monitored monthly during one year. In situ nutrient addition experiments were carried out in three of the lakes. Seasonal monitoring in two lakes revealed a thermal stratification of the water column between October and June, with a small temperature difference between epi‐ and hypolimnion (2–3 °C). Oxygen depletion of the hypolimnion towards the end of the stratification period indicated that no complete mixing of the water column occurred during stratification. There was no evidence of depletion of nutrients in the epilimnion or accumulation in the hypolimnion during stratification. There were also no clear seasonal changes in chlorophyll‐a (Chl‐a) concentration nor in phytoplankton community composition in the two lakes. Inputs of dissolved organic carbon (DOC) from the vegetated catchment resulted in high DOC concentrations (median 2.9 mg L−1) compared to temperate mountain lakes. Water transparency was relatively low, with a median extinction coefficient for photosynthetic active radiation of 0.50 m−1 and for UV‐B radiation of 10.13 m−1. Although the thermocline was deep and water transparency was low, estimates of the critical depth for photosynthesis were deeper than the mean water depth in all lakes, suggesting that phytoplankton was not light limited. The phytoplankton community was dominated by chlorophytes (e.g. Oocystis), diatoms (small Cyclotella spp.) or small colonial cyanobacteria (Aphanocapsa, Merismopedia). The zooplankton community was either dominated by large cladocerans and cyclopoid copepods, or by the calanoid copepod Boeckella occidentalis. Total concentrations of phosphorus (P) and nitrogen (N) were comparable to those in temperate mountain lakes (4–35 μg P L−1 and 162–758 μg N L−1) while Chl‐a concentrations were in the lower range (<1 μg L−1). A large part of the total nutrient pool consists of dissolved organic N and P that appeared to have a low bioavailability to phytoplankton. The median seston N:P ratio of 44, a positive correlation between Chl‐a and total P concentration, as well as nutrient addition assays carried out in three lakes all pointed to P limitation of phytoplankton.

Young guayusa leaves have potential applications as a functional ingredient in food and pharmaceutical industries. © 2017 Society of Chemical Industry.

Background and purpose: Acute intraperitoneal (i.p.) administration of cholecystokinin (CCK) is known to induce a significant, but short-lasting, reduction in food intake, followed by recovery within hours. Therefore, we had covalently coupled CCK to a 10 kDa polyethylene glycol and showed that this conjugate, PEG-CCK 9 , produced a significantly longer anorectic effect than unmodified CCK 9 . The present study assessed the dose-dependency of this response and the effect of two selective CCK 1 receptor antagonists, with different abilities to cross the blood-brain barrier (BBB), on PEG-CCK 9 -induced anorexia. Experimental approach: Food intake was measured, for up to 23 h, after i.p. administration of different doses (2, 4, 8, 16 and 32 mg kg À1 ) of CCK 9 or PEG-CCK 9 in male Wistar rats. Devazepide (100 mg kg À1 ), which penetrates the BBB or 2-NAP (3 mg kg À1 ), which does not cross the BBB, were coadministered i.p. with PEG-CCK 9 (6 mg kg À1 ) and food intake was monitored. Key results: In PEG-CCK 9 -treated rats, a clear dose-dependency was seen for both the duration and initial intensity of the anorexia whereas, for CCK 9 , only the initial intensity was dose-dependent. Intraperitoneal administration of devazepide or 2-NAP, injected immediately prior to PEG-CCK 9 , completely abolished the anorectic effect of PEG-CCK 9 . Conclusions and implications: The duration of the anorexia for PEG-CCK 9 was dose-dependent, suggesting that PEGylation of CCK 9 increases its circulation time. Both devazepide and 2-NAP completely abolished the anorectic effect of i.p. PEG-CCK 9 indicating that its anorectic effect was solely due to stimulation of peripheral CCK 1 receptors.