The role of the brown bear Ursus arctos as a legitimate megafaunal seed disperser
Megafaunal frugivores can consume large amounts of fruits whose seeds may be dispersed over long distances, thus, affecting plant regeneration processes and ecosystem functioning. We investigated the role of brown bears (Ursus arctos) as legitimate megafaunal seed dispersers. We assessed the quantity component of seed dispersal by brown bears across its entire distribution based on information about both the relative frequency of occurrence and species composition of fleshy fruits in the diet of brown bears extracted from the literature. We assessed the quality component of seed dispersal based on germination experiments for 11 fleshy-fruited plant species common in temperate and boreal regions and frequently eaten by brown bears. Across its distribution, fleshy fruits, on average, represented 24% of the bear food items and 26% of the total volume consumed. Brown bears consumed seeds from at least 101 fleshy-fruited plant species belonging to 24 families and 42 genera, of which Rubus (Rosaceae) and Vaccinium (Ericaceae) were most commonly eaten. Brown bears inhabiting Mediterranean forests relied the most on fleshy fruits and consumed the largest number of species per study area. Seeds ingested by bears germinated at higher percentages than those from whole fruits, and at similar percentages than manually depulped seeds. We conclude that brown bears are legitimate seed dispersers as they consume large quantities of seeds that remain viable after gut passage. The decline of these megafaunal frugivores may compromise seed dispersal services and plant regeneration processes.
Application of stimuli-responsive materials for extraction purposes
Stimuli-responsive materials, frequently designated as “smart/intelligent materials”, can modify their structure or properties by either a biological, physical, or chemical stimulus which, if properly controlled, could be used for specific applications. Such materials have been studied and exploited in several fields, like electronics, photonics, controlled drugs administration, imaging and medical diagnosis, among others, as well as in Analytical Chemistry where they have been used as chromatographic stationary phases, as part of sensors and for extraction purposes. This review article pretends to provide an overview of the most recent applications of these materials (mostly polymeric materials) in sample preparation for extraction purposes, as well as to provide a general vision of the current state-of-the-art of this field, their potential use and future applications.
González-Sálamo, Javier; Ortega-Zamora, Cecilia; Carrillo Fumero, Romen; Hernández-Borges, Javier
Polyoxygenated anti-inflammatory biscembranoids from the soft coral Sarcophyton tortuosum and their stereochemistry
Five novel biscembranoids, ximaolides H–L (1–5), along with four known related compounds (6–9) were isolated from the Hainan soft coral Sarcophyton tortuosum. The structures of the new compounds were determined by extensive spectroscopic analysis, quantum chemical calculations, and/or by comparing their CD spectra with those of the known compounds. Compounds 1 and 2 are the first examples of biscembranoids bearing a 1, 35-bridged lactone moiety, 4 is the first biscembranoid comprising an uncommon oxetane ring, and 5 represents the first 36-peroxyl biscembranoid. Ximaolides I (2), K (4) and F (9) exhibited interesting anti-inflammatory activity by the inhibition of LPS-induced TNF-α protein release in RAW264.7 macrophages.