New combinations and re-lectotypification in the genus Imbralyx (Fabaceae: Millettieae)

Imbralyx R. Geesink (Fabaceae: Millettieae) was long recognized as part of the genus Fordia Hemsl. However, Imbralyx has a unique characteristic combination of characters within Millettieae and it can be readily distinguished from Fordia and other genera of the tribe, including transitional inflorescences to pseudoracemes, distinctly imbricate calyx lobes in buds, spindle-shaped flowerbuds, white flowers, distinct hypanthium, monadelphous stamens, and glabrous leaflets with raised nervation on both surfaces. Recent molecular evidence also suggested that Imbralyx should be treated as a genus distinct from Fordia, because the two genera were placed respectively in two different main subclades within the core Millettieae, i.e. Canavanine group and Non-canavanie group, which is consistent with previous chemical evidence. So far the genus Imbralyx comprises nine species and two varieties from Asia, but only one epithet has been definitely associated with the generic name. Therefore, ten new combinations in Imbralyx are proposed in this paper. Additionally, lectotypes are re-designated here for the two basionyms Millettia albiflora Prain and M. unifoliata Prain.

Activated Charcoal Pellets as an Innovative Method for Forensic Analysis of Ignitable Liquid Residues from Fire Debris by GC-MS

In Forensic Chemistry, evidence collected at a crime scene is of paramount importance for any case to be properly elucidated. Ignitable liquid residues are important chemical evidence in investigations into cases of fire because these substances can be correlated to arson. Here, we describe an innovative technique for sampling and extracting gasoline and diesel from fire debris by using activated charcoal pellets (ACP). ACP can be an alternative to activated charcoal strips and can be easily produced on the laboratory scale. The ACP approach allowed all the target compounds selected for gasoline and diesel fuels to be extracted. Among the six tested extraction conditions, optimal extraction occurred at 100 °C, after 240 min. These preliminary results showed the potential of ACP for detecting gasoline and diesel in fire debris. However, the ACP approach still requires analytical validation, so that its applicability in an authentic forensic setting can be explored.

Multi-omics profiling of Earth's biomes reveals that microbial and metabolite composition are shaped by the environment

Microbes produce an array of secondary metabolites that perform diverse functions from communication to defense. These metabolites have been used to benefit human health and sustainability. In their analysis of the Genomes from Earth's Microbiomes (GEM) catalog, Nayfach and co-authors observed that, whereas genes coding for certain classes of secondary metabolites are limited or enriched in certain microbial taxa, "specific chemistry is not limited or amplified by the environment, and that most classes of secondary metabolites can be found nearly anywhere". Although metagenome mining is a powerful way to annotate biosynthetic gene clusters (BCGs), chemical evidence is required to confirm the presence of metabolites and comprehensively address this fundamental hypothesis, as metagenomic data only identify metabolic potential. To describe the Earth's metabolome, we use an integrated omics approach: the direct survey of metabolites associated with microbial communities spanning diverse environments using untargeted metabolomics coupled with metagenome analysis. We show, in contrast to Nayfach and co-authors, that the presence of certain classes of secondary metabolites can be limited or amplified by the environment. Importantly, our data indicate that considering the relative abundances of secondary metabolites (i.e., rather than only presence/absence) strengthens differences in metabolite profiles across environments, and that their richness and composition in any given sample do not directly reflect those of co-occurring microbial communities, but rather vary with the environment.

Analysis of Differentiated Chemical Components between Zijuan Purple Tea and Yunkang Green Tea by UHPLC–Orbitrap–MS/MS Combined with Chemometrics

Zijuan tea (Camellia sinensis var. assamica cv. Zijuan) is a unique purple tea. Recently, purple tea has drawn much attention for its special flavor and health benefits. However, the characteristic compounds of purple tea compared with green tea have not been reported yet. The present study employed a non-targeted metabolomics approach based on ultra-high performance liquid chromatography (UHPLC)-Orbitrap-tandem mass spectrometry (MS/MS) for comprehensive analysis of characteristic metabolites between Zijuan purple tea (ZJT) and Yunkang green tea (YKT). Partial least squares-discriminant analysis (PLS-DA) indicated that there are significant differences in chemical profiles between ZJT and YKT. A total of 66 major differential metabolites included catechins, proanthocyanins, flavonol and flavone glycosides, phenolic acids, amino acids and alkaloids were identified in ZJT. Among them, anthocyanins are the most characteristic metabolites. Nine glycosides of anthocyanins and six glycosides of proanthocyanins were found to be significantly higher in ZJT than that in YKT. Subsequently, pathway analysis revealed that ZJT might generate anthocyanins and proanthocyanins through the flavonol and flavone glycosides. Furthermore, quantitative analysis showed absolutely higher concentrations of total anthocyanins in ZJT, which correlated with the metabolomics results. This study presented the comprehensive chemical profiling and the characterized metabolites of ZJT. These results also provided chemical evidence for potential health functions of ZJT

The Peculiar Hydrology of West-Central Florida’s Sandhill Wetlands, Ponds, and Lakes – Part 1: Physical & Chemical Evidence of Connectivity to a Regional Water-Supply Aquifer

The sandhill wetlands, ponds, and lakes of west-central Florida, USA, are an understudied, poorly understood variant of geographically isolated features. Their karst origin and xeric setting impart a characteristic ecohydrology, which is a function of their connectivity to a regional water-supply aquifer. This study describes their general hydrologic character and provides physical and chemical evidence of this connectivity. These findings advance fundamental understanding of sandhill wetland/water ecohydrology and endeavor to ensure their proper management and protection amidst increasing groundwater demands, ever-expanding development, and a changing climate.Water level elevations and/or geochemistry were compared for 12 wetlands, five ponds, two lakes, and 12 monitor wells (10 constructed in limestone, two in surficial sand) in west-central Florida. Hydrograph and regression analyses indicate widely ranging water levels for most features and wells that are similar in elevation and very highly correlated with each other (0.84<R2<0.99). Water geochemistry varies from rainwater to water in contact with limestone as a function of feature depth relative to the depth of the rainwater-limestone water mixing zone. Results suggest sandhill wetland/water features are surface water expressions of the underlying regional aquifer hydrology, distinguishing them from isolated features elsewhere and establishing them as a groundwater endmember along the hydrologic continuum.

Honey-collecting in prehistoric West Africa from 3500 years ago

Honey and other bee products were likely a sought-after foodstuff for much of human history, with direct chemical evidence for beeswax identified in prehistoric ceramic vessels from Europe, the Near East and Mediterranean North Africa, from the 7th millennium BC. Historical and ethnographic literature from across Africa suggests bee products, honey and larvae, had considerable importance both as a food source and in the making of honey-based drinks. Here, to investigate this, we carry out lipid residue analysis of 458 prehistoric pottery vessels from the Nok culture, Nigeria, West Africa, an area where early farmers and foragers co-existed. We report complex lipid distributions, comprising n-alkanes, n-alkanoic acids and fatty acyl wax esters, which provide direct chemical evidence of bee product exploitation and processing, likely including honey-collecting, in over one third of lipid-yielding Nok ceramic vessels. These findings highlight the probable importance of honey collecting in an early farming context, around 3500 years ago, in West Africa.