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Phenazine natural products are a class of colored nitrogen-containing heterocycles produced by various microorganisms mainly originating from marine and terrestrial sources. The tricyclic ring molecules show various chemical structures and the decorating groups dedicate extensive pharmacological activities, including antimicrobial, anticancer, antiparasitic, anti-inflammatory, and insecticidal. These secondary metabolites provide natural materials for screening and developing medicinal compounds in the field of medicine and agriculture due to biological activities. The review presents a systematic summary of the literature on natural phenazines in the past decade, including over 150 compounds, such as hydroxylated, O-methylated, N-methylated, N-oxide, terpenoid, halogenated, glycosylated phenazines, saphenic acid derivatives, and other phenazine derivatives, along with their characterized antimicrobial and anticancer activities. This review may provide guidance for the investigation of phenazines in the future. [ABSTRACT FROM AUTHOR]

The present research was carried out in stands of Scots pine and black pine, pure or mixed with deciduous trees, installed on degraded lands from the Curvature Subcarpathian area, Romania, in a representative network of permanent research plots and followed the analysis of the structural diversity and stability indicators of these stands at different ages and in different conditions of degraded lands. The relationships between the quantitative variables with reference to the structure were established by analyzing the significance of the Pearson correlation coefficient (r) and also including datasets of slenderness indexes, which were classed into three domains of vulnerability to abiotic factors (like wind and snow). The compositional diversity of pine stands (pure or mixed with deciduous ones) is different in relation to age and is correlated with the structural diversity. The obtained correlation coefficients (r Pearson) express very strong and significant relationships between biometric parameters (h x Dbh, h x Lc%, Dc x Dbh, and Lc% x Dbh) of the structural diversity (r = 0.800–0.930), which is important for the analysis of the stability and vulnerability of pine forests. The strong correlation between the analyzed variables expresses a weak vulnerability to the action of harmful abiotic factors and the increase in the stability and resilience of the studied stands, especially of over 50 years old. In the old pine stands, the low-vulnerability domain (I < 0.80) is the best represented one, with an average of 64.01% from the total number of trees. At this age, trees with DBH > 22 cm fall into the low-vulnerability category. The explanation is that the stands were affected in their youth by the action of snow and wind, which, combined with the silvotechnical works performed, led to their compositional and structural diversification and increased stability. The young (<45 years) and pure-pine stands with higher consistency (>0.8) and even-aged structure are the most vulnerable to abiotic factors due to the fact that a large number of trees are passing gradually into the higher cenotic classes. [ABSTRACT FROM AUTHOR]

Accurately assessing tree mortality probability in the context of global climate changes is important for formulating scientific and reasonable forest management scenarios. In this study, we developed a climate-sensitive individual tree mortality model for Masson pine using data from the seventh (2004), eighth (2009), and ninth (2014) Chinese National Forest Inventory (CNFI) in Hunan Province, South–Central China. A generalized linear mixed-effects model with plots as random effects based on logistic regression was applied. Additionally, a hierarchical partitioning analysis was used to disentangle the relative contributions of the variables. Among the various candidate predictors, the diameter (DBH), Gini coefficient (GC), sum of basal area for all trees larger than the subject tree (BAL), mean coldest monthly temperature (MCMT), and mean summer (May–September) precipitation (MSP) contributed significantly to changes in Masson pine mortality. The relative contribution of climate variables (MCMT and MSP) was 44.78%, larger than tree size (DBH, 32.74%), competition (BAL, 16.09%), and structure variables (GC, 6.39%). The model validation results based on independent data showed that the model performed well and suggested an influencing mechanism of tree mortality, which could improve the accuracy of forest management decisions under a changing climate. [ABSTRACT FROM AUTHOR]

Abstract Structure, stability, electronic structure, spectroscopy and chemical bonding properties of a fluorine atom doped gas-phase small to medium-sized magnesium clusters, FMgn (n = 2–20), systematically investigated by CALYPSO software together with density functional theory (DFT). Structural calculations showed that FMgn has a structural diversity which is rarely reported in other magnesium-based clusters before. F atoms were always located in the outer layer of the Mgn host clusters and only two or three Mg atoms surround it. FMg18 was revealed to be supposed to have robust relative stability. Charge transfer and density of states were calculated for analyzing the electronic structure characteristics. Theoretical calculations of IR, Raman and UV–Vis spectra were computed to provide data guidelines for future experimental observations. Finally, the F–Mg and Mg–Mg chemical bonds of the FMgn clusters were analyzed, including the critical bonding points (BCPs) of Laplacian of electron density (Δρ), electron localization function (ELF) and interaction region indicator (IRI). The kind and strength of chemical bonds reveal the mechanism by which the F atom was rapidly stabilized by Mgn (n = 2–20) host clusters.

Carbohydrates, which are a vital dietary component, undergo digestion and gut fermentation through microbial enzymes to produce beneficial short-chain fatty acids. Certain carbohydrates selectively modulate the gut microbiota, impacting host health. Carbohydrate-active enzymes within the gut microbiota significantly contribute to carbohydrate utilization and microbial diversity. Despite their importance, the structural complexity of carbohydrates poses analytical challenges. However, recent advancements, notably, mass spectrometry, have allowed for their characterization and functional analysis. This review examines the intricate relationship between dietary carbohydrates and the gut microbiota, highlighting the crucial role of advanced analytical techniques in understanding their diversity and implications. These advancements provide valuable insights into carbohydrate bioactivity. Integrating high-throughput analysis with next-generation sequencing provides deeper insights into gut microbial interactions, potentially revealing which carbohydrate structures are beneficial for gut health. [ABSTRACT FROM AUTHOR]

Glycosylation is one of the most common and important modifications in natural products (NPs), which can alter the biological activities and properties of NPs, effectively increase structural diversity, and improve pharmacological activities. The biosynthesis of glycosylation in natural products involves multiple complex biological processes, which are coordinated by many enzymes. UDP-glycosyltransferases (UGTs) play a crucial role in glycosylation modification, and have attracted long-term and widespread research attention. UGTs can catalyze the O-, C-, S-, and N-glycosylation of different substrates, producing a variety of glycosides with broad biological activity, while improving the solubility, stability, bioavailability, pharmacological activity, and other functions of NPs. In recent years, the rapid development of synthetic biology and advanced manufacturing technologies, especially the widespread application of artificial intelligence in the field of synthetic biology, has led to a series of new discoveries in the biosynthesis of NP glycosides by UGT. This work summarizes the latest progress and challenges in the field of NP glycosylation, covering the research results and potential applications of glycosylated derivatives of terpenes, flavonoids, polyphenols, aromatic compounds, and other compounds in terms of biogenesis. Looking to the future, research may leverage artificial intelligence-driven synthetic biology techniques to decipher genes related to the synthetic pathway, which is expected to further promote the large-scale synthesis and application of glycosylated NPs, and increase the diversity of NPs in the pharmaceutical, functional food, and cosmetic industries. [ABSTRACT FROM AUTHOR]

Imidazolidinone derivatives have emerged as promising anticancer agents, captivating the attention of researchers in medicinal chemistry. Imidazolidinones, characterized by their unique chemical structure, have demonstrated versatility in synthetic methodologies. Researchers have developed a variety of derivatives, each with distinct modifications, allowing for fine‐tuning of pharmacological properties. This review explores the journey of imidazolidinone compounds, from synthesis to structure‐activity exploration, and investigates their anticancer mechanistic pathways. The synthesis methodologies, including diverse approaches and reaction conditions, were examined. Structural modifications are discussed, showing the versatility sof imidazolidinone scaffolds. Mechanistic insights into their anticancer mechanisms, in vitro, ex‐vivo and in vivo activities, with their challenges in development are critically analyzed. This paper concludes by emphasizing the potential of imidazolidinone derivatives and suggesting future research directions in the pursuit of novel and effective anticancer therapeutics. [ABSTRACT FROM AUTHOR]

The escalating crisis of antimicrobial resistance (AMR) underscores the urgent need for novel antimicrobials. One promising strategy is the exploration of structural diversity, as diverse structures can lead to diverse biological activities and mechanisms of action. This review delves into the role of structural diversity in antimicrobial discovery, highlighting its influence on factors such as target selectivity, binding affinity, pharmacokinetic properties, and the ability to overcome resistance mechanisms. We discuss various approaches for exploring structural diversity, including combinatorial chemistry, diversity-oriented synthesis, and natural product screening, and provide an overview of the common mechanisms of action of antimicrobials. We also describe techniques for investigating these mechanisms, such as genomics, proteomics, and structural biology. Despite significant progress, several challenges remain, including the synthesis of diverse compound libraries, the identification of active compounds, the elucidation of complex mechanisms of action, the emergence of AMR, and the translation of laboratory discoveries to clinical applications. However, emerging trends and technologies, such as artificial intelligence, high-throughput screening, next-generation sequencing, and open-source drug discovery, offer new avenues to overcome these challenges. Looking ahead, we envisage an exciting future for structural diversity-oriented antimicrobial discovery, with opportunities for expanding the chemical space, harnessing the power of nature, deepening our understanding of mechanisms of action, and moving toward personalized medicine and collaborative drug discovery. As we face the continued challenge of AMR, the exploration of structural diversity will be crucial in our search for new and effective antimicrobials. [ABSTRACT FROM AUTHOR]

Examining the changes in woody plant structural diversity along an inverse elevation-dependent warming gradient will enhance our mechanistic understanding of how warming affects forest communities because such an inverse elevational gradient reflects a warming trend in a mountain landscape. Here, we investigated the effects of warming on the patterns of species composition and structural diversity in a subtropical broadleaved forest. We calculated a warming index based on elevational difference and modeled the aspect-related potential incident radiation (PDIR) using nonparametric multiplicative regression. We tested the changes in structural diversity of three communities for significant differences along the warming gradient. We associated both the warming index and PDIR with the principal components and tested their relationships for significant differences. We found that trees of different sizes varied in their response to the warming gradient. While a significant decreasing trend was exhibited in both species diversity and size diversity for trees of all sizes and for adult trees along the warming gradient, no significant changes in seedlings were found, and the average basal area value was the highest for the warmest community. Our findings demonstrated that a short-range elevational gradient was adequate to separate the communities in species composition and structural diversity. Patterns of structural diversity along the warming gradient varied in size classes. The community at a higher elevation had more indicator species that were unique in separating the community from others. Principal component analysis showed that the first two principal components were negatively correlated with the warming index, indicating that warming destabilized species composition and community structure. Our study suggests that warming is the major driver of changes in structural diversity and species composition of woody plant communities in a subtropical broadleaved forest and that warming may promote tree productivity at the community level but reduce structural diversity at the quadrat level. [ABSTRACT FROM AUTHOR]

Research question/issue: We examine whether and how board diversity, measured by demographics (i.e., board gender, cultural diversity, tenure, social capital, expertise, and age) and structural diversity (i.e., board independence, size, board seat accumulation‐chair, board compensation, and board meeting frequency), influence corporate eco‐innovation. Research findings/insights: Utilizing a global sample of publicly listed companies for the period 2004–2019, we find that a one‐standard deviation increase in demographic and structural diversity translates into 4.66% and 7.11% higher corporate eco‐innovation, respectively. Furthermore, we discover that demographic and structural diversity promotes eco‐innovation by offsetting the negative effects of political risk. In an additional analysis, we find evidence that, in the absence of greater external monitoring (institutional investors and analyst following), organizations benefit more from the monitoring role of board diversity. Theoretical/academic implications: By adopting the concept of "bundling the governance mechanisms," our study adds to the ongoing discourse about the function of board diversity in addressing corporate climate footprints by offering original evidence that board diversity heterogeneity—demographic and structural diversity—matters for corporate eco‐innovation. Practitioner/policy implications: Given the increasing pressure on companies to manage their environmental impacts and carbon footprints, our paper has significant ramifications for those involved in promoting eco‐innovative business practices, such as policymakers, regulators, and practitioners. [ABSTRACT FROM AUTHOR]

Prenylation plays a pivotal role in the diversification and biological activities of natural products. This study presents the functional characterization of TolF, a multiple prenyltransferase from Tolypocladium inflatum. The heterologous expression of tolF in Aspergillus oryzae, coupled with feeding the transformed strain with paxilline, resulted in the production of 20- and 22-prenylpaxilline. Additionally, TolF demonstrated the ability to prenylated the reduced form of paxilline, β-paxitriol. A related prenyltransferase TerF from Chaunopycnis alba, exhibited similar substrate tolerance and regioselectivity. In vitro enzyme assays using purified recombinant enzymes TolF and TerF confirmed their capacity to catalyze prenylation of paxilline, β-paxitriol, and terpendole I. Based on previous reports, terpendole I should be considered a native substrate. This work not only enhances our understanding of the molecular basis and product diversity of prenylation reactions in indole diterpene biosynthesis, but also provides insights into the potential of fungal indole diterpene prenyltransferase to alter their position specificities for prenylation. This could be applicable for the synthesis of industrially useful compounds, including bioactive compounds, thereby opening up new avenues for the development of novel biosynthetic strategies and pharmaceuticals. Key points: • The study characterizes TolF as a multiple prenyltransferase from Tolypocladium inflatum. • TerF from Chaunopycnis alba shows similar substrate tolerance and regioselectivity compared to TolF. • The research offers insights into the potential applications of fungal indole diterpene prenyltransferases. [ABSTRACT FROM AUTHOR]

Over the past 40 years, global tertiary expansion has been driven in part by the rise of the non-university sector. The growth of this sector, which includes vocational colleges, also contributes to increasingly diverse national higher education systems. Prior research has focused on inter-state variation in national systems, while very few studies have explored intra-state variation in the expansion of non-university sector. Building on the policy innovation and diffusion model, this study uses event history analysis to investigate key drivers behind Chinese prefecture cities' adoption of vocational colleges during the latest tertiary education expansion. The study employs a rich panel dataset from 273 Chinese cities between 2000 and 2014. Findings suggest that the socioeconomic and the politico-institutional contexts matter the most for cities' policy adoption, and the influence of policy diffusion is negative but not significant. Moreover, there is substantial heterogeneity across time and region. The characteristics of early adopters significantly differ from those of late adopters, and the diffusion paths vary within and across regions. This study illustrates that the emergence of sub-national government affiliated non-university institutions is driven by a complex combination of socioeconomic, politico-institutional, and policy forces. Results highlight the regional contextual factors that may override coercive pressure from national strategies to promote the non-university sector expansion and the structural diversity in the context of less developed economies. [ABSTRACT FROM AUTHOR]

AbstractGrowing demand for the tasty and healthy food has driven the development of low-calorie sweeteners, sweet taste modulators, and bitter masking compounds originated from natural sources. With the discovery of human taste receptors, increasing numbers of sweet taste modulators have been identified through human taste response and molecular docking techniques. However, the discovery of novel taste-active molecules in nature can be accelerated by using advanced spectrometry technologies based on structure-activity relationships (SARs). SARs explain why structurally similar compounds can elicit similar taste qualities. Given the characterization of structural information from reported data, strategies employing SAR techniques to find structurally similar compounds become an innovative approach to expand knowledge of sweeteners. This review aims to summarize the structural patterns of known natural non-nutritive sweeteners, sweet taste enhancers, and bitter masking compounds. Innovative SAR-based approaches to explore sweetener derivatives are also discussed. Most sweet-tasting flavonoids belong to either the flavanonols or the dihydrochalcones and known bitter masking molecules are flavanones. Based on SAR findings that structural similarities are related to the sensory properties, innovative methodologies described in this paper can be applied to screen and discover the derivatives of taste-active compounds or potential taste modulators. [ABSTRACT FROM AUTHOR]

The tree crown is a useful measure of tree vigour and is highly relevant to a tree's environmental adaptability. Crown allometry depends on environmental and stand conditions. Several studies have focussed on the effects of climate change and competitive intensity on the crown, but the regulatory role of soil resources and diversity on crown allometry and carbon allocation has been neglected.Data from 20,994 trees in 232 mixed forests collected between 2011 and 2019 were located near four major mountain ranges in northeast China. The proposed crown width model includes the stand developmental stage, soil, climate, competition intensity, species mixture, species diversity, structural diversity and their interactions.We observed that the cross‐species allometric scaling exponent does not conform to the universal scaling law. Our results showed that crown width increased with increasing soil bulk density, quadratic mean diameter and coefficient of diameter variation but decreased with increasing de Martonne aridity index, basal area, Simpson index and species mixture. The interaction between quadratic mean diameter and soil bulk density had a significant negative effect on crown width. The influence of a particular factor within the interaction term on crown width was modulated by the gradients of other factors. Furthermore, soil bulk density contributed more to crown width modelling than the aridity index, and structural diversity had a greater effect on crown width than species diversity.Synthesis. Our results provide new insights into the environmental variability of crown allometry in mixed forests under global change, which is critical for improving regional and global estimates of forest biomass and carbon stocks. [ABSTRACT FROM AUTHOR]

Austin was first isolated as a novel polyisoprenoid mycotoxin from Aspergillus ustus in 1976. Subsequently, some new austin-type meroterpenoids (ATMTs) have been continually found. This review attempts to give a comprehensive summary of progress on the isolation, chemical structural features, biological activities, and fungal biodiversity of 104 novel ATMTs from 5 genera of terrestrial- and marine-derived fungi reported from October 1976 to January 2023. The genera of Penicillium and Aspergillus are the two dominant producers, producing 63.5% and 30.8% of ATMTs, respectively. Moreover, about 26.9% of ATMTs display various pronounced bioactivities, including insecticidal, anti-inflammatory, cytotoxicity, antibacterial, and PTP1B inhibitory activities. The chemical diversity and potential activities of these novel fungal ATMTs are reviewed for a better understanding, and a relevant summary focusing on the source fungi and their taxonomy is provided to shed light on the future development and research of austin-type meroterpenoids. [ABSTRACT FROM AUTHOR]

Structural diversity guided steroidal thiazolidin-4-one conjugates were designed and synthesized based on six steroid skeletons mainly including androst-4-ene-3,17-dione, dehydroepiandrosterone, epiandrosterone, androst-1,4-diene-3,17-dione, dienedione and 9α-hydroxy-androst-4-ene-3,17-dione. Their in vitro inhibition activities against cell proliferation were fully investigated, and some of which exhibited good antiproliferative activities as potential CDK1 inhibitor. The detailed analysis of structure–activity relationships (SARs) based on the inhibition activities, kinase assay, and molecular docking model demonstrated that the structure of different steroidal core ring skeleton as well as the N substituents of the thiazolidin-4-one ring influenced the inhibitory activity on cancer cell lines. Especially, compounds 15c and 16c have certain inhibitory effects on the tyrosine protein kinases CDK1/CyclinA2, ALK, CDK6/CyclinD1, FGFR1 and PIM2. Compounds 16c displayed highest inhibitory effect on the kinases of CDK1/CyclinA2 with inhibition rate 56.38 % at the concentration of 10 μM, which induced cell death in A875 cells at least partly (initially), by apoptosis.

Phenazine natural products are a class of colored nitrogen-containing heterocycles produced by various microorganisms mainly originating from marine and terrestrial sources. The tricyclic ring molecules show various chemical structures and the decorating groups dedicate extensive pharmacological activities, including antimicrobial, anticancer, antiparasitic, anti-inflammatory, and insecticidal. These secondary metabolites provide natural materials for screening and developing medicinal compounds in the field of medicine and agriculture due to biological activities. The review presents a systematic summary of the literature on natural phenazines in the past decade, including over 150 compounds, such as hydroxylated, O-methylated, N-methylated, N-oxide, terpenoid, halogenated, glycosylated phenazines, saphenic acid derivatives, and other phenazine derivatives, along with their characterized antimicrobial and anticancer activities. This review may provide guidance for the investigation of phenazines in the future.

The present research was carried out in stands of Scots pine and black pine, pure or mixed with deciduous trees, installed on degraded lands from the Curvature Subcarpathian area, Romania, in a representative network of permanent research plots and followed the analysis of the structural diversity and stability indicators of these stands at different ages and in different conditions of degraded lands. The relationships between the quantitative variables with reference to the structure were established by analyzing the significance of the Pearson correlation coefficient (r) and also including datasets of slenderness indexes, which were classed into three domains of vulnerability to abiotic factors (like wind and snow). The compositional diversity of pine stands (pure or mixed with deciduous ones) is different in relation to age and is correlated with the structural diversity. The obtained correlation coefficients (r Pearson) express very strong and significant relationships between biometric parameters (h x Dbh, h x Lc%, Dc x Dbh, and Lc% x Dbh) of the structural diversity (r = 0.800–0.930), which is important for the analysis of the stability and vulnerability of pine forests. The strong correlation between the analyzed variables expresses a weak vulnerability to the action of harmful abiotic factors and the increase in the stability and resilience of the studied stands, especially of over 50 years old. In the old pine stands, the low-vulnerability domain (I < 0.80) is the best represented one, with an average of 64.01% from the total number of trees. At this age, trees with DBH > 22 cm fall into the low-vulnerability category. The explanation is that the stands were affected in their youth by the action of snow and wind, which, combined with the silvotechnical works performed, led to their compositional and structural diversification and increased stability. The young (0.8) and even-aged structure are the most vulnerable to abiotic factors due to the fact that a large number of trees are passing gradually into the higher cenotic classes.

Accurately assessing tree mortality probability in the context of global climate changes is important for formulating scientific and reasonable forest management scenarios. In this study, we developed a climate-sensitive individual tree mortality model for Masson pine using data from the seventh (2004), eighth (2009), and ninth (2014) Chinese National Forest Inventory (CNFI) in Hunan Province, South–Central China. A generalized linear mixed-effects model with plots as random effects based on logistic regression was applied. Additionally, a hierarchical partitioning analysis was used to disentangle the relative contributions of the variables. Among the various candidate predictors, the diameter (DBH), Gini coefficient (GC), sum of basal area for all trees larger than the subject tree (BAL), mean coldest monthly temperature (MCMT), and mean summer (May–September) precipitation (MSP) contributed significantly to changes in Masson pine mortality. The relative contribution of climate variables (MCMT and MSP) was 44.78%, larger than tree size (DBH, 32.74%), competition (BAL, 16.09%), and structure variables (GC, 6.39%). The model validation results based on independent data showed that the model performed well and suggested an influencing mechanism of tree mortality, which could improve the accuracy of forest management decisions under a changing climate.

Discussions of ‘diversity’ in higher education are often limited to structural diversity (i.e. access to higher education based on demographic variables), which is just one form of diversity that impacts student learning outcomes. Others include curricular diversity (a measure of the interdisciplinary of the coursework) and interactional diversity (a measure of informal interaction). This study aims to explore the effects of all three categories of diversity on the academic performance of college students. Using data from a top higher education institution in Taiwan, we construct indicators of curricular diversity (i.e. curricular evenness (CE), ratio of elective credits (REC), ratio of inter-collegiate credits (RIC), and interdisciplinary experience (IDE). Interactional diversity was measured using student's participation in activities involving interaction with others, and structural diversity was measured by student's personal and contextual characteristics. Our goal was to determine which of these forms of diversity impacted students’ self-reported skills in interdisciplinary communication (ICS) and collaborative problem solving (CPS). Results show that curricular diversity is significantly associated with interactional diversity. In terms of learning outcomes, curricular and structural diversity are associated with both ICS and CPS, while interactional diversity is associated with CPS. Interactional diversity also moderates the relationships between curricular diversity and ICS as well as CPS. This research implies that institutions of higher education need to promote curricular and interactive diversity to fix systemic biases that limit or relate to structural diversity. [ABSTRACT FROM AUTHOR]

Small scattered plots of a few hundred square meters well reflect structural variability at stand level, but not at small spatial scales as the data between plots is missing. Information about structural similarities between managed and unmanaged stands, especially based on large sample plots, is still scarce. Our first objective was to quantify and illustrate structural variability of a selection-managed stand and a corresponding old-growth (OG) stand at small spatial scales. The second goal was to find out if there is a positive autocorrelation among neighboring patches in these stands regarding tree density (N) and basal area (BA). Tree positions and their diameters were recorded in 1.5 ha plots. Structural variation was examined at scales from 0.01 ha to 0.36 ha. Spatial correlation of N and BA was examined by applying experimental semivariograms. The variability of N was similar in both stands, whereas it significantly differed regarding BA (α = 0.05). Semivariance did not detect positive spatial autocorrelation of BA, while adjacent plots appeared to be more similar (autocorrelated) regarding N in both stands. Despite statistical difference regarding BA variability, the selection-managed stand exhibited many structural similarities to the OG stand, which makes it potentially suitable for modulating, if needed, to bring it step closer to an old-growth structure. [ABSTRACT FROM AUTHOR]

Increasing agricultural intensification, combined with land transformation and fragmentation, poses significant threats to biodiversity. While extensively cultivated landscapes serve as vital refuges against biodiversity loss, they are modified by land abandonment and intensification. Orchard meadows in Central Europe represent traditional extensive land management systems, exhibiting high biodiversity. Comprising cultivated grasslands and scattered fruit trees, orchard meadows feature structures rich in different habitats supporting a diverse flora and fauna. However, their decreasing economic importance in recent decades has resulted in severe degradation or abandonment. Despite their importance for biodiversity conservation, there remains no comprehensive overview of orchard meadow biodiversity and management in Central Europe. This review aims to summarize existing knowledge on orchard meadows' role in biodiversity conservation and the effects of management practices on habitat diversity and quality at both smaller (structure and microhabitats, local scale) and larger scales (surrounding landscape, regional scale). The first part focuses on orchard meadow biodiversity, including both plants and animals and their link to landscape-scale factors. Biodiversity in orchard meadows is predominantly affected by patch size, determining species richness and composition, and connectivity to neighbouring orchard meadows, influencing species migration and recolonization success. The second part evaluates management impacts, illustrating differences in the benefits of mowing versus grazing across taxonomic groups. An intermediate management intensity for orchard meadows determines their conservation value in terms of species composition, varying among different taxonomic groups. To prevent area loss and abandonment of orchard meadows, we advocate for political and public support, along with incentives for farmers to maintain their biodiversity. [ABSTRACT FROM AUTHOR]

The relationships between species diversity and size structure complexity on above ground biomass (AGB) have theoretical and practical applications for biodiversity conservation and sustainable forest management. The relationships become more complex in the high-species diversity of tropical forests and heterogeneous environmental conditions. To disentangle the complicated relationships, structural equation models were applied to examine the relative effects of species and tree size diversity on above ground biomass under different topographical conditions of two tropical evergreen forest stands. Our results showed that: (i) species diversity contributes greater to AGB in the forest stand under homogeneous topography. (ii) Structural diversity positively affected AGB in the heterogeneous topographical stand. (iii) Slope revealed a negative effect on species diversity but positive effects on structural diversity and AGB in both studied plots. We concluded that maintaining high-stand structural diversity enhances above ground biomass and local topographical conditions constrain the relationship between species and size diversity in the study area. [ABSTRACT FROM AUTHOR]

This article provides an overview of the total synthesis of 2,2'-biindolyl alkaloids using a cyanide-catalyzed imino-Stetter reaction. The authors discuss the unique structural features and biological activities of 2,2'-biindolyl natural products and propose a new protocol for their synthesis. They also review the total syntheses of several 2,2'-biindolyl natural products and describe a synthetic method for the preparation of 2,2'-bisindole-3-acetic acid derivatives. The authors successfully synthesized arcyriaflavin A and developed a novel synthetic route for iheyamines A and B. Ongoing research is focused on exploring the application of this reaction in the synthesis of other indole alkaloids. [Extracted from the article]

Heterologous biosynthesis has become an effective means to activate fungal silent biosynthetic gene clusters (BGCs) and efficiently utilize fungal genetic resources. Herein, thirteen labdane diterpene derivatives, including five undescribed ones named talarobicins A–E (3–7), were discovered via heterologous expression of a silent BGC (labd) in Aspergillus nidulans. Their structures with absolute configurations were elucidated using extensive MS and NMR spectroscopic methods, as well as electronic circular dichroism (ECD) calculations. These labdanes belong to four skeleton types, and talarobicin B (4) is the first 3,18-dinor-2,3:4,18-diseco-labdane diterpene with the cleavage of the C2–C3 bond in ring A and the decarboxylation at C-3 and C-18. Talarobicin B (4) represents the key intermediate in the biosynthesis of penioxalicin and compound 13. The combinatorial heterologous expression and feeding experiments revealed that the cytochrome P450 enzymes LabdC, LabdE, and LabdF were responsible for catalyzing various chemical reactions, such as oxidation, decarboxylation, and methylation. All of the compounds are noncytotoxic, and compounds 2 and 8 displayed inhibitory effects against methicillin-resistant coagulase-negative staphylococci (MRCNS) and Bacillus cereus. [ABSTRACT FROM AUTHOR]

α-Amylase is a generally acknowledged molecular target of a distinct class of antidiabetic drugs named α-glucosidase inhibitors. This class of medications is scarce and rather underutilized, and treatment with current commercial drugs is accompanied by unpleasant adverse effects. However, mammalian α-amylase inhibitors are abundant in nature and form an extensive pool of high-affinity ligands that are available for drug discovery. Individual compounds and natural extracts and preparations are promising therapeutic agents for conditions associated with impaired starch metabolism, e.g., diabetes mellitus, obesity, and other metabolic disorders. This review focuses on the structural diversity and action mechanisms of active natural products with inhibitory activity toward mammalian α-amylases, and emphasizes proteinaceous inhibitors as more effective compounds with significant potential for clinical use. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we ask whether the invasive paper mulberry (Broussonetia papyrifera) has a competitive advantage over neighbor trees in a native area. We determined the competitive capacity of paper mulberry in three deciduous broad-leaved forests using structural indices including the mixing index, the tree–tree interval index, and the diameter/height differentiation index. It was found that the reference paper mulberry had a slight competitive advantage over neighboring trees in both the horizontal and vertical planes. Such a competitive ability may play a significant role in the ecological invasion of paper mulberry. Our findings not only help to reveal the invasion mechanism of paper mulberry, but also provide an important reference for the management and utilization of paper mulberry in invaded areas. Paper mulberry (Broussonetia papyrifera) is currently an invasive species on several continents. However, little is known about whether paper mulberry has a competitive advantage over its surrounding trees in its native distribution range, subtropical regions of China. Here, we determined the relative intraspecific and interspecific competitive capacity of paper mulberry in three subtropical deciduous broad-leaved forests using the indices of structural diversity including the mixing index, the tree–tree interval index, and the diameter/height differentiation index. It was found that more than 80% of mingling index values were not greater than 0.25, suggesting a stronger competitiveness of paper mulberry relative to other tree species. The tree–tree interval index values ranged between 1 m and 2 m, suggesting a strong competition between paper mulberry and its neighbors. Moreover, more than 60% of the height differentiation index and diameter differentiation index values were positive, suggesting that the reference paper mulberry had a slight competitive advantage over neighboring trees in both the horizontal and vertical planes. These collectively suggest a competitive advantage over other tree species in the native distribution range, which may play a significant role in the ecological invasion of paper mulberry. Our findings not only help to reveal the invasion mechanism of paper mulberry, but also provide an important reference for the management and utilization of paper mulberry in invaded areas. [ABSTRACT FROM AUTHOR]

Glycosylation is one of the most common and important modifications in natural products (NPs), which can alter the biological activities and properties of NPs, effectively increase structural diversity, and improve pharmacological activities. The biosynthesis of glycosylation in natural products involves multiple complex biological processes, which are coordinated by many enzymes. UDP-glycosyltransferases (UGTs) play a crucial role in glycosylation modification, and have attracted long-term and widespread research attention. UGTs can catalyze the O-, C-, S-, and N-glycosylation of different substrates, producing a variety of glycosides with broad biological activity, while improving the solubility, stability, bioavailability, pharmacological activity, and other functions of NPs. In recent years, the rapid development of synthetic biology and advanced manufacturing technologies, especially the widespread application of artificial intelligence in the field of synthetic biology, has led to a series of new discoveries in the biosynthesis of NP glycosides by UGT. This work summarizes the latest progress and challenges in the field of NP glycosylation, covering the research results and potential applications of glycosylated derivatives of terpenes, flavonoids, polyphenols, aromatic compounds, and other compounds in terms of biogenesis. Looking to the future, research may leverage artificial intelligence-driven synthetic biology techniques to decipher genes related to the synthetic pathway, which is expected to further promote the large-scale synthesis and application of glycosylated NPs, and increase the diversity of NPs in the pharmaceutical, functional food, and cosmetic industries.

Examining the changes in woody plant structural diversity along an inverse elevation-dependent warming gradient will enhance our mechanistic understanding of how warming affects forest communities because such an inverse elevational gradient reflects a warming trend in a mountain landscape. Here, we investigated the effects of warming on the patterns of species composition and structural diversity in a subtropical broadleaved forest. We calculated a warming index based on elevational difference and modeled the aspect-related potential incident radiation (PDIR) using nonparametric multiplicative regression. We tested the changes in structural diversity of three communities for significant differences along the warming gradient. We associated both the warming index and PDIR with the principal components and tested their relationships for significant differences. We found that trees of different sizes varied in their response to the warming gradient. While a significant decreasing trend was exhibited in both species diversity and size diversity for trees of all sizes and for adult trees along the warming gradient, no significant changes in seedlings were found, and the average basal area value was the highest for the warmest community. Our findings demonstrated that a short-range elevational gradient was adequate to separate the communities in species composition and structural diversity. Patterns of structural diversity along the warming gradient varied in size classes. The community at a higher elevation had more indicator species that were unique in separating the community from others. Principal component analysis showed that the first two principal components were negatively correlated with the warming index, indicating that warming destabilized species composition and community structure. Our study suggests that warming is the major driver of changes in structural diversity and species composition of woody plant communities in a subtropical broadleaved forest and that warming may promote tree productivity at the community level but reduce structural diversity at the quadrat level.

Background: Trichoderma species are rich source of bioactive secondary metabolites. In the past decades, a series of secondary metabolites were reported from different Trichoderma fungi, among which terpenoids possessing versatile structural diversities and extensive pharmacological activities are one of the particularly important categories. Aim of Review: The review aims to summarize the terpenoids isolated from Trichoderma species regarding their structural diversities, biological activities, and promising biosynthetic potentials. Key Scientific Concepts of Review: So far, a total of 253 terpenoids, including 202 sesquiterpenes, 48 diterpenes, 2 monoterpenes and 1 meroterpenoid, were isolated and identified from Trichoderma species between 1948 and 2022. Pharmacological investigations of Trichoderma terpenoids mainly focused on their antibacterial activities, antifungal activities, inhibitory activities on marine plankton species and cytotoxic activities, indicating that Trichoderma species are important microbial agents for drug discovery and environmentally friendly agrochemicals development. Intriguing chemistry and enzymology involved in the biosynthesis of Trichoderma terpenoids were also presented to facilitate further precise genome mining-guided novel structure discovery. Taken together, the abundance of novel skeletons, bioactivities and biosynthetic potentials presents new opportunities for drug and agrochemicals discovery, genome mining and enzymology exploration from Trichoderma species. The work will provide references for the profound study of terpenoids derived from Trichoderma, and facilitate further studies on Trichoderma species in the areas of chemistry, medicine, agriculture and microbiology.

Forest functionality is generally considered a byproduct of forest diversity. Perhaps unsurprisingly, many researchers associate increasing multi-functionality with increasing diversity. Diversity, however, is an often-overused word that may describe a host of features, including the diversity of species, functional trait and structure. Furthermore, variable environmental features (such as topography) influence the interaction between forest plants and their function. Incorporating complex topography (like that associated with tropical and subtropical forests) into estimates of forest functionality is challenging and highly uncertain. In this paper, we applied structural equation models to disentangle the relative importance of topography and different components of what might be considered “plant diversity” to forest multifunctionality using repeated census of a 20-ha subtropical forest plot. We found that multifunctionality was principally influenced by structural diversity more so than either species composition or functional trait diversity. In our SEM model approach, we observed variations in topography could account for about 30% of variation in multifunctionality. Furthermore, variations in topography could indirectly influence forest multifunctionality by changing species composition, functional trait diversity, and structural diversity. Our work highlights the importance of topography and forest structure in regulating subtropical forest multifunctionality on the local scale. This suggests future subtropical forest management should focus on regulating forest structure. Namely, our results suggest land managers must take topography (and the complex interaction between topography and plant diversity) into account in order to build robust and multifunctional forests.

Sustainable management and conservation of multipurpose tree species in their natural habitats is crucial, given their vulnerability to climate change and increasing human activities. This can be achieved by harnessing insights from local ecological knowledge (LEK) and classical ecological approaches to support biodiversity conservation efforts. Using forest inventory data from 126 plots and information from a semi-structured survey of 234 households, we investigated LEK (perception on population trend, causes, and conservation attitudes toward the species) and population ecology (tree density, size class distribution – SCD, structural diversity, and stability) of the endangered rosewood Pterocarpus erinaceus Poir. along a climate gradient in Benin (Sudanian (SZ), Sudano-Guinean (SGZ) and Guinean (GZ)). The results indicated that local communities were aware of the decline of P. erinaceus populations, although variations were observed with respect to ethnicity and age. The protection of the species regeneration by the communities in the GZ (63 %) probably led to the high regeneration rate (90 %) of P. erinaceus in this zone. Tree density declined from the SZ to GZ (2 and 1.23 times lower in SGZ and GZ compared to SZ), but variation in the mean diameter at breast height showed the opposite pattern (1.98 and 1.90 times lower in SGZ and SZ than in GZ). The SCD in the SGZ exhibited a bell-shaped pattern, while the populations in the SZ and GZ showed an inverted J-shaped distribution. Pruning intensity was 6.60 to 35.25 times higher in the SZ than in the SGZ and GZ, respectively, where regeneration rates were low, reflecting the potential negative effects of pruning on regeneration. Furthermore, P. erinaceus demonstrated tolerance for mixed-species stands (mingling of 40 % to 75 %), indicating an opportunity to integrate it into agroforestry systems with other species. This research highlights the impacts of human activity and climate conditions on P. erinaceus populations and informs on potential management actions needed for the conservation of the species.

Negative public sentiment built up around bisphenol A (BPA) follows growing awareness of the frequency of this chemical compound in the environment. The increase in air, water, and soil contamination by BPA has also generated the need to replace it with less toxic analogs, such as Bisphenol F (BPF) and Bisphenol S (BPS). However, due to the structural similarity of BPF and BPS to BPA, questions arise about the safety of their usage. The toxicity of BPA, BPF, and BPS towards humans and animals has been fairly well understood. The biodegradability potential of microorganisms towards each of these bisphenols is also widely recognized. However, the scale of their inhibitory pressure on soil microbiomes and soil enzyme activity has not been estimated. These parameters are extremely important in determining soil health, which in turn also influences plant growth and development. Therefore, in this manuscript, knowledge has been expanded and systematized regarding the differences in toxicity between BPA and its two analogs. In the context of the synthetic characterization of the effects of bisphenol permeation into the environment, the toxic impact of BPA, BPF, and BPS on the microbiological and biochemical parameters of soils was traced. The response of cultivated plants to their influence was also analyzed. [ABSTRACT FROM AUTHOR]

Naturally occurring benzophenones represent a relatively small group of plant metabolites with narrow distribution, mainly in members of Clusiaceae, Gentianaceae, Hypericaceae, Polygalaceae, Myrtaceae, etc.; however, there were reports of several compounds derived from microorganisms belonging to the Aspergillaceae and Valsaceae families and propolis. Benzophenones exhibit many biological activities, such as antioxidant, anti-inflammatory, cytotoxic, antimicrobial, etc. Few reviews on benzophenones that have appeared in the literature were focused on their prenylated derivatives. Summarized information on structural diversity, distribution, and biological activities of simple oxygenated naturally occurring benzophenones and their glycosides has not been found in the literature. Until 2000, only benzophenone C-glycosides were known to occur in nature. Since then, many O-glycosides have been isolated, structurally, and biologically characterized. This review covers the years from 1850 to 2023 and was compiled using databases such as Chemical Abstracts, Scopus, Google Scholar, PubMed, and ResearchGate. Based on their degree of oxidation, 210 chemical structures of benzophenone derivatives and glycosides were grouped into six categories. In addition, in one group of 40 miscellaneous benzophenones, where one or several protons are replaced by a methyl, alcohol, carboxyl, or acyl group, glycosidic forms with such an aglycone and dimeric compounds with xanthone was included. Simple oxygenated benzophenones and their glycosides were found in 77 plant genera belonging to 44 families. The allergy-associated bezophenone-1, benzophenone-2 and benzophenone-3 have limited distribution across natural sources. A wide range of biological activities (antioxidant, anti-inflammatory, cytotoxic, antitumor, cytoprotective, antimicrobial, MAO-A, antiarthritic, anticholinesterase, anti-atherosclerotic, laxative, etc.) of simple oxygenated benzophenones and their glycosides that appeared in the literature were discussed. [ABSTRACT FROM AUTHOR]

Main conclusion: Biphenyl and dibenzofuran phytoalexins are differentially distributed among species of the rosaceous subtribe Malinae, which includes apple and pear, and exhibit varying inhibitory activity against phytopathogenic microorganisms. Biphenyls and dibenzofurans are specialized metabolites, which are formed in species of the rosaceous subtribe Malinae upon elicitation by biotic and abiotic inducers. The subtribe Malinae (previously Pyrinae) comprises approximately 1000 species, which include economically important fruit trees such as apple and pear. The present review summarizes the current status of knowledge of biphenyls and dibenzofurans in the Malinae, mainly focusing on their role as phytoalexins. To date, 46 biphenyls and 41 dibenzofurans have been detected in 44 Malinae species. Structurally, 54 simple molecules, 23 glycosidic compounds and 10 miscellaneous structures were identified. Functionally, 21 biphenyls and 21 dibenzofurans were demonstrated to be phytoalexins. Furthermore, their distribution in species of the Malinae, inhibitory activities against phytopathogens, and structure–activity relationships were studied. The most widely distributed phytoalexins of the Malinae are the three biphenyls aucuparin (3), 2ʹ-methoxyaucuparin (7), and 4ʹ-methoxyaucuparin (9) and the three dibenzofurans α-cotonefuran (47), γ-cotonefuran (49), and eriobofuran (53). The formation of biphenyl and dibenzofuran phytoalexins appears to be an essential defense weapon of the Malinae against various stresses. Manipulating phytoalexin formation may enhance the disease resistance in economically important fruit trees. However, this approach requires an extensive understanding of how the compounds are formed. Although the biosynthesis of biphenyls was partially elucidated, formation of dibenzofurans remains largely unclear. Thus, further efforts have to be made to gain deeper insight into the distribution, function, and metabolism of biphenyls and dibenzofurans in the Malinae. [ABSTRACT FROM AUTHOR]

The isolation and identification of an increasing number of secondary metabolites featuring unique skeletons and possessing diverse bioactivities sourced from marine microorganisms have garnered the interest of numerous natural product chemists. There has been a growing emphasis on how to cultivate microorganisms to enhance the chemical diversity of metabolites and avoid the rediscovery of known ones. Given the significance of secondary metabolites as a means of communication among microorganisms, microbial co-culture has been introduced. By mimicking the growth patterns of microbial communities in their natural habitats, the co-culture strategy is anticipated to stimulate biosynthetic gene clusters that remain dormant under traditional laboratory culture conditions, thereby inducing the production of novel secondary metabolites. Different from previous reviews mainly focusing on fermentation conditions or metabolite diversities from marine-derived co-paired strains, this review covers the marine-derived co-culture microorganisms from 2012 to 2022, and turns to a particular discussion highlighting the selection of co-paired strains for marine-derived microorganisms, especially the fermentation methods for their co-cultural apparatus, and the screening approaches for the convenient and rapid detection of novel metabolites, as these are important in the co-culture. Finally, the structural and bioactivity diversities of molecules are also discussed. The challenges and prospects of co-culture are discussed on behave of the views of the authors. [ABSTRACT FROM AUTHOR]

The measurement of forest structure has evolved steadily due to advances in technology, methodology, and theory. Such advances have greatly increased our capacity to describe key forest structural elements and resulted in a range of measurement approaches from traditional analog tools such as measurement tapes to highly derived and computationally intensive methods such as advanced remote sensing tools (e.g., lidar, radar). This assortment of measurement approaches results in structural metrics unique to each method, with the caveat that metrics may be biased or constrained by the measurement approach taken. While forest structural diversity (FSD) metrics foster novel research opportunities, understanding how they are measured or derived, limitations of the measurement approach taken, as well as their biological interpretation is crucial for proper application. We review the measurement of forest structure and structural diversity—an umbrella term that includes quantification of the distribution of functional and biotic components of forests. We consider how and where these approaches can be used, the role of technology in measuring structure, how measurement impacts extend beyond research, and current limitations and potential opportunities for future research. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms underlying the relationship between biodiversity and ecosystem function (BEF) is critical for the implementation of productive and resilient ecosystem management. However, the differences in BEF relationships along altitudinal gradients between forests and shrublands are poorly understood, impeding the ability to manage terrestrial ecosystems and promote their carbon sinks. Using data from 37962 trees of 115 temperate forest and 134 shrubland plots of Taihang Mountains Priority Reserve, we analyzed the effects of species diversity, structural diversity, climate factors and soil moisture on carbon storage along altitudinal gradients in temperate forests and shrublands. We found that: (1) Structural diversity, rather than species diversity, mainly promoted carbon storage in forests. While species diversity had greater positive effect on carbon storage in shrublands. (2) Mean annual temperature (MAT) had a direct negative effect on forest carbon storage, and indirectly affected forest carbon storage by inhibiting structural diversity. In contrast, MAT promoted shrubland carbon storage directly and indirectly through the positive mediating effect of species diversity. (3) Increasing altitudinal gradients enhanced the structural diversity-carbon relationship in forests, but weakened the species diversity-carbon relationship in shrublands. Niche and architectural complementarity and different life strategies of forests and shrubs mainly explain these findings. These differential characteristics are critical for our comprehensive understanding of the BEF relationship and could help guide the differentiated management of forests and shrublands in reaction to environmental changes. [ABSTRACT FROM AUTHOR]

Synthetic chemicals have been widely used in modern agriculture as fertilizer, plant growth regulators and pesticides. Although the chemical inputs improved the crop production, it is well known about their negative effects, such as environmental residues in water, soil and animals, pest resistance and resurgence and the residues in agricultural produces. The demands for safer food and more friendly environment are now more preferred by humankind in the world. Microbes have already become an alternate for chemical inputs in some aspects in agriculture. The microbes can produce very diverse volatile organic compounds (mVOCs) which play important roles in the interactions between plant and microbes, or among intraspecies or interspecies of microbes. Many mVOCs showed diverse agroactivities, such as insecticidal, bactericidal, fungicidal, herbicidal, plant growth promotion and abiotic stress-tolerance inducing activities. The agroactive mVOCs have diverse structure-types, such as alkane, alkenes, alcohols, aldehydes, ketones, carboxylic acid, esters and lactones, ethers, aromatic ring, terpenes, heterocycles, sulphur-containing VOCs. The promising agroactive properties make it possible to apply mVOCs and their producing microorganisms or synthetic mimics or agroactive mVOCs in crop protection, and so this review focuses on the chemical diversity, agroactivities, and potential application of mVOCs.

Austin was first isolated as a novel polyisoprenoid mycotoxin from Aspergillus ustus in 1976. Subsequently, some new austin-type meroterpenoids (ATMTs) have been continually found. This review attempts to give a comprehensive summary of progress on the isolation, chemical structural features, biological activities, and fungal biodiversity of 104 novel ATMTs from 5 genera of terrestrial- and marine-derived fungi reported from October 1976 to January 2023. The genera of Penicillium and Aspergillus are the two dominant producers, producing 63.5% and 30.8% of ATMTs, respectively. Moreover, about 26.9% of ATMTs display various pronounced bioactivities, including insecticidal, anti-inflammatory, cytotoxicity, antibacterial, and PTP1B inhibitory activities. The chemical diversity and potential activities of these novel fungal ATMTs are reviewed for a better understanding, and a relevant summary focusing on the source fungi and their taxonomy is provided to shed light on the future development and research of austin-type meroterpenoids.

Sansanmycins represent a family of uridyl peptide antibiotics with antimicrobial activity specifically against Mycobacterium tuberculosis (including drug-resistant M. tuberculosis) and Pseudomonas aeruginosa. They target translocase I (MraY) to inhibit bacterial cell wall assembly. Given the unique mechanism of action, sansanmycin has emerged as a potential lead compound for developing new anti-tuberculosis drugs, while the 5′-aminouridine moiety plays a crucial role in the pharmacophore of sansanmycin. For expanding the structural diversity of the 5′-aminouridine moiety of sansanmycin through biosynthetic methods, we firstly demonstrated that SsaM and SsaK are responsible for the biosynthesis of the 5′-aminouridine moiety of sansanmycin in vivo. Using the ssaK deletion mutant (SS/KKO), we efficiently obtained a series of new analogues with modified 5′-aminouridine moieties through mutational biosynthesis. Based on molecular networking analysis of MS/MS, twenty-two new analogues (SS-KK-1 to -13 and SS-KK-A to -I) were identified. Among them, four new analogues (SS-KK-1 to -3 and SS-KK-C) were purified and bioassayed. SS-KK-2 showed better antibacterial activity against E. coli ΔtolC than the parent compound sansanmycin A. SS-KK-3 showed the same anti-TB activity as sansanmycin A against M. tuberculosis H37Rv as well as clinically isolated, drug-sensitive and multidrug-resistant M. tuberculosis strains. Furthermore, SS-KK-3 exhibited significantly improved structural stability compared to sansanmycin A. The results suggested that mutasynthesis is an effective and practical strategy for expanding the structural diversity of 5′-aminouridine moiety in sansanmycin.

Social networks shape and reflect economic life. Prior studies have identified long ties, which connect people who lack mutual contacts, as a correlate of individuals’ success within firms and places’ economic prosperity. However, we lack population- scale evidence of the individual-level link between long ties and economic prosperity, and why some people have more long ties remains obscure. Here, using a social network constructed from interactions on Facebook, we establish a robust association between long ties and economic outcomes and study disruptive life events hypothesized to cause formation of long ties. Consistent with prior aggregated results, administrative units with a higher fraction of long ties tend to have higher-income and economic mobility. Individuals with more long ties live in higher-income places and have higher values of proxies for economic prosperity (e.g., using more Internet-connected devices and making more donations). Furthermore, having stronger long ties (i.e., with higher intensity of interaction) is associated with better outcomes, consistent with an advantage from the structural diversity constituted by long ties, rather than them being weak ties per se. We then study the role of disruptive life events in the formation of long ties. Individuals who have migrated between US states, have transferred between high schools, or have attended college out-of-state have a higher fraction of long ties among their contacts many years after the event. Overall, these results suggest that long ties are robustly associated with economic prosperity and highlight roles for important life experiences in developing and maintaining long ties. [ABSTRACT FROM AUTHOR]

Identifying new environmental resistance determinants is significant to combat rising antibiotic resistance. Herein we report the unexpected correlation of a lobophorin (LOB) resistance‐related glycosidase KijX with the host‐dependent chemical diversity of LOBs, by a process of glycosylation, deglycosylation and reglycosylation. KijX homologues are widespread among bacteria, archaea and fungi, and encode the same glycohydrolytic activity on LOBs. The crystal structure of AcvX (a KijX homologue) shows a similar fold to that of the glycoside hydrolase family 113 and a special negatively charged groove to accommodate and deglycosylate LOBs. Antagonistic assays indicate kijX as a defense weapon of actinomycetes to combat LOB producers in environment, reflecting an elegant coevolution relationship. Our study provides insight into the KijX‐related glycosidases as preexisting resistance determinants and represents an example of resistance genes accidentally integrated into natural product assembly. [ABSTRACT FROM AUTHOR]

Metal Organic Frameworks (MOFs), built from metal ions/clusters coordinated by organic linkers/bridging ligands, have emerged as an extensive class of crystalline hybrid materials with exceptional ultrahigh porosity and enormous internal surface areas. Out of several hallmarks possessed by MOFs, one is their topologically diverse and aesthetically pleasing framework structures which can be adjusted and tuned with the state-of-art techniques, and molecular simulations, different geometry, and connectivity of a linker to the respective metal cluster. In this critical review, we intend to highlight the scope of carboxylate-based MOFs by providing a varied range from their topology analysis and molecular simulations to different synthetic routes. Moreover, providing insights to reticular chemistry of carboxylate MOFs and the importance of Post-Synthetic Modification (PSM), an alternative route to introduce functional groups within these MOFs. We have also tried to identify the possible loopholes that can provide an extensive opportunity to young researchers that can lead to a detailed exploration in the field of novel MOFs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Trichoderma species from soil and plants are rich source of bioactive secondary metabolites. • A total of 253 terpenoids with diverse skeletons and bioactivities were isolated from Trichoderma species. • The promising biosynthetic potential of Trichoderma species for terpenoid diversity were generalized and discussed. • Trichoderma species are of great significance for exploring drug lead compounds and potential application in agriculture. Trichoderma species are rich source of bioactive secondary metabolites. In the past decades, a series of secondary metabolites were reported from different Trichoderma fungi, among which terpenoids possessing versatile structural diversities and extensive pharmacological activities are one of the particularly important categories. The review aims to summarize the terpenoids isolated from Trichoderma species regarding their structural diversities, biological activities, and promising biosynthetic potentials. So far, a total of 253 terpenoids, including 202 sesquiterpenes, 48 diterpenes, 2 monoterpenes and 1 meroterpenoid, were isolated and identified from Trichoderma species between 1948 and 2022. Pharmacological investigations of Trichoderma terpenoids mainly focused on their antibacterial activities, antifungal activities, inhibitory activities on marine plankton species and cytotoxic activities, indicating that Trichoderma species are important microbial agents for drug discovery and environmentally friendly agrochemicals development. Intriguing chemistry and enzymology involved in the biosynthesis of Trichoderma terpenoids were also presented to facilitate further precise genome mining-guided novel structure discovery. Taken together, the abundance of novel skeletons, bioactivities and biosynthetic potentials presents new opportunities for drug and agrochemicals discovery, genome mining and enzymology exploration from Trichoderma species. The work will provide references for the profound study of terpenoids derived from Trichoderma , and facilitate further studies on Trichoderma species in the areas of chemistry, medicine, agriculture and microbiology. [ABSTRACT FROM AUTHOR]

Secoiridoids are natural products of cyclopentane monoterpene derivatives that are formed by splitting the rings of cyclomethene oxime compounds at C‐7 and C‐8, and only account for a small part of cyclic ether terpenoids. Because of the chemically active hemiacetal structure in their common basic skeleton, secoiridoids have a wide range of biological activities, such as neuroprotective, anti‐inflammatory, antidiabetic, hepatoprotective, and antinociceptive activities. Phenolic secoiridoids can also act against multiple molecular targets involved in human tumorigenesis, making them potentially valuable precursors for antitumor drug development. This review provides a detailed update, covering relevant discoveries from January 2011 to December 2020, about the occurrence, structural diversity, bioactivities, and synthesis of naturally occurring secoiridoids. We aimed to resolve the lack of extensive, specific, and thorough review of secoiridoids, as well as open new areas for pharmacological investigation and better drugs based on these compounds. Highlights: 1.This review summarizes the discovery of new biological activities and mechanisms of action of secoiridoids from 2011 to 2020. We also discuss the prospects of the promising bioavailability and clinical applications of these active secoiridoids.2.More than 200 secoiridoids have been reported. More importantly, based on the existing rough category principles, we made a more systematic and detailed classification of secoiridoids and named some newly discovered structural subtypes.3.Here, we have reimagined the findings from many newly published studies and hypotheses of the classical secoiridoid biosynthesis pathway. In addition, synthetic, semisynthetic, and chemical conversion strategies for some representative compounds are discussed. [ABSTRACT FROM AUTHOR]

Creating native woodland is a policy goal globally, and one strategy to maximize woodland creation benefits in limited space is to target efforts to extend existing woodlands. There is evidence to support spatially targeting habitat creation for biodiversity, however, there is little evidence of how this affects a habitat's structural development. Here, a space‐for‐time study using light detection and ranging (LiDAR) data assesses how the structure of recently created woodlands, are affected by the presence of an adjacent older woodland. Recently created native woodlands were identified across the Isle of Wight UK using historical maps and satellite imagery. Canopy height and foliage height diversity were derived for all woodlands from LiDAR data collected at two different time points (2011 and 2021), and linear models were used to test for any differences in these structural metrics between sites with an adjacent older woodland, and those without. The percentage change in woodland height between the two time points was also tested. In woodlands created adjacent to older woodlands, canopy height was found to be higher by an average of nearly 2 m, and foliage height diversity was found to be on average 4.7% higher, using the 2021 data. Growth rates between 2011 and 2021 were not significantly different between the groups, although young adjacent woodlands grew the most on average. This research shows that creating woodlands adjacent to existing older woodlands reduces the time taken to create tall and to a lesser extent structurally diverse habitat, which may lead to early biodiversity benefits. [ABSTRACT FROM AUTHOR]