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Computational insights into Sitahe (Leuconotis eugenifolia) bioactive compounds: A promising approach for radioprotection through p53 inhibition
No full textThe radioprotective potential of Sitahe (Leuconotis eugenifolia) phytochemicals in cancer radiotherapy remains largely unexplored. In this study, in silico docking simulations were conducted to systematically assess the ability of key phytochemicals from Sitahe to modulate p53 activity, a critical gene in DNA repair and cancer therapy. SwissADME analysis revealed favorable physicochemical properties for compounds such as baurenol, alpha amyrin, and beta amyrin, although high lipophilicity may pose challenges for bioavailability. Molecular docking studies identified strong binding affinities between these compounds and the p53 DNA binding domain, with baurenol demonstrating the highest binding affinity at −6.75 kcal/mol, which is better compared to rhazinilam (−4.55 kcal/mol), leuconolam (−4.36 kcal/mol), leuconoxine (−4.26 kcal/mol), and dehydroleuconoxine (−4.76 kcal/mol). Hydrogen bonding with key residues such as Thr123 further enhanced the stability of these complexes. The low inhibition constants (Ki) suggest significant inhibitory potential, particularly for baurenol (11.31 μM). To evaluate the stability and reliability of these interactions, molecular dynamics (MD) simulations were performed over a duration of 500 ns. The results demonstrated that the selected compounds maintained stable molecular dynamics profiles, showing consistent interactions with the target protein throughout the simulation period. Among the compounds tested, baurenol exhibited the best performance with a MM/PBSA binding energy of −68.568 kJ/mol, which is better than rhazinilam (−63.538 kJ/mol). These findings suggest that baurenol, along with other Sitahe phytochemicals, could serve as dual-function agents, offering protection to healthy tissues from radiation-induced damage while targeting cancer cells through p53 modulation. Although these in silico and MD results are promising, further validation through in vitro and in vivo studies is essential to confirm their therapeutic potential and optimize their pharmacokinetic properties. This study positions Sitahe phytochemicals, particularly baurenol, as promising candidates for the development of novel radioprotective agents in cancer treatment
Bird diversity in different vegetation types in the Pacific coastal plain of Guatemala
No full textGuatemala’s Pacific coastal plain, although largely dominated by agricultural land, still contains patches of diverse vegetation that could be vital for supporting bird diversity. Despite the country’s recognition for its rich avian biodiversity, updated data on species richness in this region are still lacking. Understanding the role of different vegetation types in maintaining bird diversity is essential for developing targeted conservation strategies that can both preserve and improve biodiversity in these fragmented landscapes. In this study, we compared species richness and the composition of bird communities across four distinct vegetation types along Guatemala’s Pacific coastal plain and analyzed species turnover and replacement to understand how these habitats contribute to maintaining overall bird diversity at the study site. The avian community consisted predominantly of species adapted to open habitats, with generalist bird species prevailing and only a limited representation of species typical of the understory in subtropical wet forests. Additionally, the observed species turnover value suggests a moderate level of species replacement among different vegetation types at the study site. The moderate nestedness, wherein species-poor communities are subsets of more diverse ones, further implies a decline in overall biodiversity. These findings suggest that the homogenization of the avian community indicates that our study focused on isolated areas that remain in this transformed environment. Our findings argue that protecting and restoring seminatural patches, even modestly sized patches, can be critical for safeguarding biodiversity in human-dominated landscapes and highlight the importance of landscape-level conservation, which enables connectivity between habitat patches to support species with different ecological requirements
Bertiera acutiflora (Rubiaceae, Bertiereae), a new combination based on the overlooked Psychotria acutiflora
No full textPsychotria acutiflora was described in 1830 by de Candolle in his Prodromus, and was based on a single collection by Thaddäus Haenke from near Guayaquil, Ecuador. Although the identity of the name has never been studied since its original publication, it is currently treated as a species endemic to Ecuador. It is shown here that the type of the name belongs to Bertiera procumbens, which was described much later. Therefore, the new combination Bertiera acutiflora is provided here for the Columbian and Ecuadorian endemic and a lectotype is designated for the name
Optimization of sago starch and sodium alginate crosslink, including calcium chloride as a capsule alternative using the simplex lattice design
No full textBackground: Capsule shells are conventionally manufactured using gelatine, primarily sourced from bovine or porcine bones and skins, which presents significant concerns for Muslim consumers. This study seeks to optimize sago starch and sodium alginate crosslinking as viable alternatives to conventional gelatine-derived capsules. Methods: Utilizing calcium chloride (CaCl₂) as a crosslinking agent, three formulations were developed: F1 (100% sago starch), F2 (50% sago starch, 50% sodium alginate), and F3 (100% sodium alginate). The Simplex Lattice Design (SLD) was employed to determine the optimal capsule characteristics. Results: Formula F2 showed optimal characteristics with 8.165% weight uniformity deviation, 49.607% water swelling, and a destruction time of 9 minutes, 25 seconds. FTIR confirmed hydroxyl groups with absorption shifts of 1463.6–1389.06 cm-1 in F2 and 1476.7–1394.81 cm-1 in F3. Conclusion: CaCl₂ proved effective for crosslinking sago starch and sodium alginate. SLD identified a 10% starch, 90% alginate ratio as optimal, enhancing capsule uniformity and stability
Three new species of Apiospora (Amphisphaeriales, Apiosporaceae) in China
No full textChina is located in eastern Asia and has a large quantity and rich variety of bamboo resources. Bamboo resources also contain various fungal species such as Apiospora. The genus Apiospora is commonly used as plant pathogens, endophytes, and saprophytes, which are widely present in various host ranges around the world. The discovery of metabolites has been proven to play an important role in the pharmaceutical industry. Recently, 10 strains were isolated from bamboo in Guizhou Province, China, which were identified as five species of Apiospora based on multigene phylogenetic analysis of ITS, LSU, TEF1-α, and TUB2, and morphological observations, including two recognized species, Ap. arundinis and Ap. lophatheri, and three novel species, viz. Ap. bambusicaulis, Ap. bambusirimae, and Ap. bambusilentiginis. Illustrations and descriptions of these taxa are provided
Two new species of Psen Latreille, 1796 (Hymenoptera, Apoidea, Crabronidae) from China, with a key to Psen species of China
No full textTwo new species of the genus Psen Latreille, 1796, namely Psen fronistriatus sp. nov. and Psen scabrosus sp. nov. are described and illustrated from China. A key to the Chinese species of Psen is also provided
Control planning for invasive crayfish: the case of Pacifastacus leniusculus (Decapoda, Astacidae) in the Clitunno River (Central Italy).
No full textThe signal crayfish Pacifastacus leniusculus (Dana, 1852) is one of the most ecologically impactful decapod crustaceans introduced in Europe. As a species of Union concern, early detection and rapid eradication measures are required to prevent its establishment and spread. We aimed to: i) test the effectiveness of the control plan prepared within the LIFE IMAGINE IPE/IT/000015 project to contrast the diffusion and contain demographic growth of P. leniusculus in the Clitunno River basin (Central Italy), where the species has been detected in 2020; ii) assess distribution, age structure and growth of P. leniusculus in this invaded area. The removal actions were conducted biweekly, from June 2022 to December 2024, using both traps and electrofishing. Biometric parameters were individually recorded, and the demographic features and growth of P. leniusculus population were assessed. In total, 259 removal actions were carried out and a biomass of 39.74 Kg has been removed. Maximum size (Total Length = 14.8 cm) was consistent with what has been reported for another Italian population, but greater than some native Californian ones. The presence of six cohorts (from 0+ to 5+), including the young-of-the-year (0+), attested the quick acclimatization of P. leniusculus, which gave rise to a self-sustaining population in a short time. The greatest removal efforts have been concentrated on a small tributary, named Fosso Vecchio, where the average values of Catch Per Unit Effort (CPUE) showed a significant decreasing trend over time, arguing in favour of the removal actions' effectiveness. Our findings provided some evidence that early detection and control measures conducted at a small scale, applying strong catching efforts, represent effective management tools to limit population abundance and prevent invasive crayfish from spreading further
Protist ecology in Patagonian peatlands: pH, organic phosphorus, and sulfate as key drivers of testate amoeba diversity in undisturbed ecosystems
No full textPeatlands in southern Chile, particularly in the remote Aysén region, provide unique ecosystems that remain understudied despite their ecological significance. Testate amoebae, a group of shelled protists, are important components of these ecosystems due to their roles in nutrient cycling and their sensitivity to environmental changes, which make them valuable bioindicators. However, research on the ecological drivers shaping their diversity and community composition in Chilean peatlands remains scarce. This study investigates the spatial distribution and diversity of testate amoebae across five peatlands in the Aysén region. By analyzing environmental variables such as pH, dissolved organic carbon, and sulfate, we identify key factors influencing community structure. Our findings highlight significant spatial turnover in testate amoeba communities, suggesting that local environmental gradients strongly shape their distribution. Notably, the Sphagnum-dominated peatlands exhibit higher diversity compared to mixed vegetation peatlands. The redundancy analysis reveals that organic phosphorus, pH, and sulfate are the most influential variables affecting testate amoeba communities. This study fills a critical gap in the understanding of microbial biodiversity in Chilean peatlands and underscores the importance of conserving these near-pristine ecosystems as reservoirs of microbial diversity and natural archives of environmental change
Potentially Pathogenic Yeasts to Humans Isolated From Sandy Beaches Used For Recreational Purposes
No full textYeasts possess a range of environmental adaptations that allow them to colonize soil and sand. They can circulate seasonally between different components of lake ecosystems, including beach sand, water, and the coastal phyllosphere. The accumulation of people on beaches promotes the development and transmission of yeasts, posing an increasing sanitary and epidemiological risk. The aim of this study was to determine the species and quantitative composition of potentially pathogenic and pathogenic yeasts for humans present in the sand of supervised and unsupervised beaches along the shores of lakes in the city of Olsztyn (north-eastern Poland).The study material consisted of sand samples collected during two summer seasons (2019; 2020) from 12 research sites on sandy beaches of 4 lakes located within the administrative boundaries of Olsztyn. Standard isolation and identification methods used in diagnostic mycological laboratories were applied.A total of 259 yeast isolates (264, counting species in two-species isolates separately) belonging to 62 species representing 47 genera were obtained during the study. Among all the isolates, 5 were identified as mixed (two-species). Eight isolated species were classified into biosafety level 2 (BSL-2) and risk group 2 (RG-2). The highest average number of viable yeast cells was found in sand samples collected in July 2019 (5,56 x 102 CFU/g), August, and September 2020 (1,03 x 103 CFU/g and 1,94 x 103 CFU/g, respectively). The lowest concentrations were in samples collected in April, September, and October 2019, and October 2020 (1,48 x 102 CFU/g, 1,47 x 102 CFU/g, 1,40 x 102 CFU/g, and 1,40 x 102 CFU/g, respectively)
A new tree species of Compsoneura (Myristicaceae) from the Andean forests on the Eastern Cordillera Range, Colombia
No full textCompsoneura crassitepala, a new species of Myristicaceae is described, illustrated and its morphological relationships with related species are discussed. This new species is found in Andean forests between 1400 and 1900 m a.s.l., located in the mountainous area of the Magdalena River Basin, Department of Boyacá, Colombia. Compsoneura crassitepala closely resembles Compsoneura lapidiflora in having a thick perianth in pistillate flowers. However, it differs by its leaves, which exhibit weak and partially brochidodromous venation with dendritic trichomes featuring a single axis on the underside. Additionally, it has floral characteristics such as a zig-zag pattern in the rachis direction of inflorescence and unusually thick, fleshy tepals in staminate flowers. Moreover, C. crassitepala is a remarkable species recorded at higher altitudes in Colombia, in an otherwise predominantly lowland forests genus (below 1550 m). A taxonomic key for the identification of the species of the genus is provided