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Six new nostocyclophanes and four known compounds have been isolated from Nostoc linckia (Nostocaceae) cyanobacterial strain UTEX B1932. The new compounds, nostocyclophanes E–J (1–6), were characterized by NMR and MS techniques. The known compounds were nostocyclophanes B–D, previously isolated from this strain, and dedichloronostocyclophane D. Structural modifications on the new [7.7]paracyclophane analogs 1–5, isolated from the 80% methanol fraction, range from simple changes such as the lack of methylation or halogenation to more unusual modifications such as those seen in nostocyclophane H (4), in which the exocyclic alkyl chains are of different length; this is the first time this modification has been observed in this family of natural products. In addition, nostocyclophane J (6) is a linear analog in which C-20 is chlorinated in preparation for the presumed enzymatic Friedel–Craft cyclization needed to form the final ring structure, analogous to the biosynthesis of the related cylindrocyclophanes. Nostocyclophane D, dedichloronostocyclophane D, and nostocyclophanes E-J demonstrated moderate to weak growth inhibition against MDA-MB-231 breast cancer cells. [ABSTRACT FROM AUTHOR]

Objectives: There are currently no baseline data regarding the amount and types of case reports produced by forensic anthropologists. This research fills that gap by providing data on caseloads of practicing forensic anthropologists and identifying variables that may contribute to amount and type of casework. Materials and methods: A survey was distributed to practicing forensic anthropologists (n = 364) to explore number of case reports written and possible influential factors. Questions included demographic information, employment type, institution where master's degree or PhD were obtained, type of reports written, professional organization membership, certification, graduate research focus, among others. Data were analyzed using summary statistics, a random forest model, network analysis, and structural equation modeling. Results: The mean number of sole‐authored skeletal analysis reports per year was 12.33 and field recovery reports was 2 per year. Statistical analyses identified several variables influencing case loads which included: number of fieldwork reports per year, current employment, total number of cases analyzed, age, publication record, and institution of doctoral degree. Network analyses revealed that individuals in academic settings tended to have a bioarchaeological research focus from their graduate work, whereas those in an applied setting had a focus on forensic anthropology. Further, degree institution influenced employment type. Discussion/conclusions: These data address expectations for the number of cases analyzed by a forensic anthropologist per year and set a baseline for expectations and performance. Based on these results, we suggest that forensic anthropology is underutilized in the medicolegal death investigation system and more forensic anthropologists should be employed within Medical Examiner/Coroner's Offices. [ABSTRACT FROM AUTHOR]

An increasing number of ecological studies have used chemical diversity as a functionally relevant, scalable measure of phytochemical mixtures, demanding more rigorous attention to how chemical diversity is estimated. Most studies have focused on the composition of phytochemical mixtures and have largely ignored structural concerns, which may have greater importance for ecological function. Here, we explore the development of structural complexity and compositional diversity resulting from different biotic and abiotic interactions in Piper kelleyi Tepe (Piperaceae). We also describe how variation in structural complexity and compositional diversity differs between two congeners, P. kelleyi and P. reticulatum. To better interpret these results, we have developed a framework for interpreting these dimensions of chemical diversity in phytochemical mixtures.We used the tropical shrub, P. kelleyi, as a model system to examine interactions between ecological factors and dimensions of phytochemical diversity. We also compared compositional diversity and metabolic complexity in P. kelleyi and P. reticulatum using liquid chromatography and 1H NMR, respectively, to examine trade‐offs between compositional diversity and structural complexity. A framework is provided to generate meaningful estimates of the structural complexity of phytochemical mixtures as measured by 1H NMR.Piper is an abundant plant genus that supports diverse insect communities throughout the tropics. Subtle changes in understorey forest light were associated with increases in herbivory that directly increased compositional diversity and indirectly decreased structural complexity in P. kelleyi. This was attributed to the production of oxidation products resulting from herbivory‐driven decomposition of structurally complex defence compounds. This type of complex result would remain undetected using standard chemical ecology approaches and accounts for the detailed molecular changes that are likely to affect species interactions.Synthesis. Our quantitative framework provides a method for considering trade‐offs between structural complexity and compositional diversity and the interpretation of analytical approaches for each. This methodology will provide new theoretical insights and a more sophisticated model for examining the ecology and evolution of chemically mediated interactions. [ABSTRACT FROM AUTHOR]

Modern metabolomic approaches that generate more comprehensive phytochemical profiles than were previously available are providing new opportunities for understanding plant‐animal interactions. Specifically, we can characterize the phytochemical landscape by asking how a larger number of individual compounds affect herbivores and how compounds covary among plants. Here we use the recent colonization of alfalfa (Medicago sativa) by the Melissa blue butterfly (Lycaeides melissa) to investigate the effects of indivdiual compounds and suites of covarying phytochemicals on caterpillar performance. We find that survival, development time, and adult weight are all associated with variation in nutrition and toxicity, including biomolecules associated with plant cell function as well as putative anti‐herbivore action. The plant‐insect interface is complex, with clusters of covarying compounds in many cases encompassing divergent effects on different aspects of caterpillar performance. Individual compounds with the strongest associations are largely specialized metabolites, including alkaloids, phenolic glycosides, and saponins. The saponins are represented in our data by more than 25 individual compounds with beneficial and detrimental effects on L. melissa caterpillars, which highlights the value of metabolomic data as opposed to approaches that rely on total concentrations within broad defensive classes. [ABSTRACT FROM AUTHOR]

Plant–insect interactions are ubiquitous, and have been studied intensely because of their relevance to damage and pollination in agricultural plants, and to the ecology and evolution of biodiversity. Variation within species can affect the outcome of these interactions. Specific genes and chemicals that mediate these interactions have been identified, but genome‐ or metabolome‐scale studies might be necessary to better understand the ecological and evolutionary consequences of intraspecific variation for plant–insect interactions. Here, we present such a study. Specifically, we assess the consequences of genome‐wide genetic variation in the model plant Medicago truncatula for Lycaeides melissa caterpillar growth and survival (larval performance). Using a rearing experiment and a whole‐genome SNP data set (>5 million SNPs), we found that polygenic variation in M. truncatula explains 9%–41% of the observed variation in caterpillar growth and survival. Genetic correlations among caterpillar performance and other plant traits, including structural defences and some anonymous chemical features, suggest that multiple M. truncatula alleles have pleiotropic effects on plant traits and caterpillar performance (or that substantial linkage disequilibrium exists among distinct loci affecting subsets of these traits). A moderate proportion of the genetic effect of M. truncatula alleles on L. melissa performance can be explained by the effect of these alleles on the plant traits we measured, especially leaf toughness. Taken together, our results show that intraspecific genetic variation in M. truncatula has a substantial effect on the successful development of L. melissa caterpillars (i.e., on a plant–insect interaction), and further point toward traits potentially mediating this genetic effect. [ABSTRACT FROM AUTHOR]

Abstract: Prenylflavonoids are an unique class of phytochemicals found in the inflorescences of the hop plant (Humulus lupulus). These flavonoids have demonstrated a wide range of biological activities, which may be influenced by their stereochemical configuration. Additionally, recent studies suggest that hop prenylflavonoids are subject to biotransformations which could alter or enrich their stereochemistry. In order to facilitate studies of the stereoisomers of flavanones, a facile method was developed for resolving the diastereomeric esters of flavanones via reversed-phase HPLC. Herein, a method for forming the tri-(1S)-(−)-camphanic acid esters of the 4′,5,7-trihydroxy flavanones naringenin, 8-prenylnaringenin and 6-prenylnaringenin, is described. The respective diastereomers were separated using analytical reversed-phase HPLC. Diastereomeric esters were isolated by preparative HPLC to >98% d.e. based on HPLC, with their absolute configurations established by application of CD spectrometry. [Copyright &y& Elsevier]

Identifying the interactions of functional, biotic, and abiotic factors that define plant–insect communities has long been a goal of community ecologists. Metabolomics approaches facilitate a broader understanding of how phytochemistry mediates the functional interactions among ecological factors. Ceanothus velutinus communities are a relatively unstudied system for investigating chemically mediated interactions. Ceanothus are nitrogen-fixing, fire-adapted plants that establish early post-fire, and produce antimicrobial cyclic peptides, linear peptides, and flavonoids. This study takes a metabolomic approach to understanding how the diversity and variation of C. velutinus phytochemistry influences associated herbivore and parasitoid communities at multiple spatiotemporal scales. Herbivores and foliar samples were collected over three collection times at two sites on the east slope of the Sierra Nevada Mountain range. Foliar tissue was subjected to LC-MS metabolomic analysis, and several novel statistical analyses were applied to summarize, quantify, and annotate variation in the C. velutinus metabolome. We found that phytochemistry played an important role in plant–insect community structure across an elevational gradient. Flavonoids were found to mediate biotic and abiotic influences on herbivores and associated parasitoids, while foliar oligopeptides played a significant positive role in herbivore abundance, even more than abundance of host plants and leaf abundance. The importance of nutritional and defense chemistry in mediating ecological interactions in C. velutinus plant–herbivore communities was established, justifying larger scale studies of this plant system that incorporate other mediators of phytochemistry such as genetic and metageomic contributions. [ABSTRACT FROM AUTHOR]