Glycoalkaloids, the biologically active secondary metabolites produced by Solanaceae plants, are natural defenses against animals, insects and fungi. In this paper, the effects of glycoalkaloids present in extracts of...Glycoalkaloids, the biologically active secondary metabolites produced by Solanaceae plants, are natural defenses against animals, insects and fungi. In this paper, the effects of glycoalkaloids present in extracts of Solanaceae plants （potato, tomato and black nightshade） or pure commercial glycoalkaloids on the coleopteran Zophobas atratus E were evaluated by in vitro and in vivo bioassays using heart experimental models. Each tested extract induced a dose-dependent cardioinhibitory effect. The perfusion of Zophobas atratus semi-isolated heart using the highest potato and tomato extract concentration （1 mmol/L） caused irreversible cardiac arrests, while extract from black nightshade pro- duced fast but reversible arrests. Pure commercial glycoalkaloids caused similar but less evident effects compared with extracts. Our results showed that the bioactivity of tested compounds depended on their structure and suggested the existence of synergistic interac- tions when combinations of the main glycoalkaloids of potato and black nightshade were used for trials. Surprisingly, injection of tomato and potato extracts in 1-day-old pupae of Zophobas atratus induced reversible positive chronotropic effects and decreased the duration of the both phases （anterograde and retrograde） of the heart contractile activity. Furthermore, these extracts affected the amplitude of the heart contractions.展开更多
Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a chari...Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a charismatic alien species in Chinese mainland and to detect the public and the media attitudes to the species,we analyzed the reports and emotional tendency from media coverage in 2000-2022 using manual reading,crawler extraction and latent Dirichlet allocation.A total of 6654 Black Swans were reported at 711 sites,including 147 individuals at 30 nature reserves.Successful breeding was reported at one-fourth of the total sites,including five nature reserves.The proportion of positive emotional tendency to Black Swans was overwhelming in the reports and was higher than that to alien species in general,suggesting that the public and the media are unaware of the risk of biological invasion.Effective management of invasive species requires the media clarifies the invasion risk of charismatic alien species.Promoting the unity between the harmfulness of abstract concept of alien species and the charisma of a specific alien species among the public help effective management.展开更多
A determination of how the color of animal integument is produced is a starting point for investigations into the function and evolution of coloration.The mechanisms that give rise to the color of bare skin of New Wor...A determination of how the color of animal integument is produced is a starting point for investigations into the function and evolution of coloration.The mechanisms that give rise to the color of bare skin of New World vultures are largely unexplored.Here,we investigate the source of color production in the bare skin of Turkey Vultures(Cathartes aura)and Black Vultures(Coragyps atratus).Using UV-vis reflectance spectroscopy,we found evidence that hemoglobin is the primary pigment responsible for the red coloration of the bare skin on the heads of Turkey Vultures,and that eumelanin is responsible for the black coloration of the bare skin on the heads of Black Vultures.Light microscopy of incisional skin samples further supported these mechanisms of color production by revealing the presence of numerous blood vessels near the surface of the Turkey Vulture skin,and a high concentration of melanosomes in the skin of Black Vultures.Using high performance liquid chromatography(HPLC),we detected carotenoids within the skin of both species with significantly higher total concentrations of carotenoids in the skin of Turkey Vultures compared to the skin of Black Vultures.The carotenoids detected were dietary carotenoids that typically produce yellow coloration when accumulated in integument and were present in low concentrations.We hypothesize that the dietary carotenoids present do not contribute to the color of the skin,but rather help to compensate for the lack of melanosomes found in Turkey Vulture skin.The presence of additional carotenoids may act as an antioxidant to minimize UV damage when the bare Turkey Vulture head skin is exposed to direct sunlight for prolonged periods of time when soaring and scavenging for food.展开更多
文摘Glycoalkaloids, the biologically active secondary metabolites produced by Solanaceae plants, are natural defenses against animals, insects and fungi. In this paper, the effects of glycoalkaloids present in extracts of Solanaceae plants （potato, tomato and black nightshade） or pure commercial glycoalkaloids on the coleopteran Zophobas atratus E were evaluated by in vitro and in vivo bioassays using heart experimental models. Each tested extract induced a dose-dependent cardioinhibitory effect. The perfusion of Zophobas atratus semi-isolated heart using the highest potato and tomato extract concentration （1 mmol/L） caused irreversible cardiac arrests, while extract from black nightshade pro- duced fast but reversible arrests. Pure commercial glycoalkaloids caused similar but less evident effects compared with extracts. Our results showed that the bioactivity of tested compounds depended on their structure and suggested the existence of synergistic interac- tions when combinations of the main glycoalkaloids of potato and black nightshade were used for trials. Surprisingly, injection of tomato and potato extracts in 1-day-old pupae of Zophobas atratus induced reversible positive chronotropic effects and decreased the duration of the both phases （anterograde and retrograde） of the heart contractile activity. Furthermore, these extracts affected the amplitude of the heart contractions.
基金financially supported by the National Key Research and Development Program of China(Number 2022YFC2601100)。
文摘Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a charismatic alien species in Chinese mainland and to detect the public and the media attitudes to the species,we analyzed the reports and emotional tendency from media coverage in 2000-2022 using manual reading,crawler extraction and latent Dirichlet allocation.A total of 6654 Black Swans were reported at 711 sites,including 147 individuals at 30 nature reserves.Successful breeding was reported at one-fourth of the total sites,including five nature reserves.The proportion of positive emotional tendency to Black Swans was overwhelming in the reports and was higher than that to alien species in general,suggesting that the public and the media are unaware of the risk of biological invasion.Effective management of invasive species requires the media clarifies the invasion risk of charismatic alien species.Promoting the unity between the harmfulness of abstract concept of alien species and the charisma of a specific alien species among the public help effective management.
基金provided for by the National Institute of Food and Agriculture,U.S.Department of Agriculture,MclntireStennis project under accession number MISZ-082100the National Science Foundation grant number IOS-2037741prepared under contract with Mississippi State University,PI Scott Rush,with financial support from the Office of Local Defense Community Adjustment,Department of Defense。
文摘A determination of how the color of animal integument is produced is a starting point for investigations into the function and evolution of coloration.The mechanisms that give rise to the color of bare skin of New World vultures are largely unexplored.Here,we investigate the source of color production in the bare skin of Turkey Vultures(Cathartes aura)and Black Vultures(Coragyps atratus).Using UV-vis reflectance spectroscopy,we found evidence that hemoglobin is the primary pigment responsible for the red coloration of the bare skin on the heads of Turkey Vultures,and that eumelanin is responsible for the black coloration of the bare skin on the heads of Black Vultures.Light microscopy of incisional skin samples further supported these mechanisms of color production by revealing the presence of numerous blood vessels near the surface of the Turkey Vulture skin,and a high concentration of melanosomes in the skin of Black Vultures.Using high performance liquid chromatography(HPLC),we detected carotenoids within the skin of both species with significantly higher total concentrations of carotenoids in the skin of Turkey Vultures compared to the skin of Black Vultures.The carotenoids detected were dietary carotenoids that typically produce yellow coloration when accumulated in integument and were present in low concentrations.We hypothesize that the dietary carotenoids present do not contribute to the color of the skin,but rather help to compensate for the lack of melanosomes found in Turkey Vulture skin.The presence of additional carotenoids may act as an antioxidant to minimize UV damage when the bare Turkey Vulture head skin is exposed to direct sunlight for prolonged periods of time when soaring and scavenging for food.
