New insight into identifying sediment phosphorus sources in multi-source polluted urban river: Effect of environmental-induced microbial community succession on stability of microbial source tracking results.

Identifying sediment phosphorus sources, the key to control eutrophication, is hindered in multi-source polluted urban rivers by the lack of appropriate methods and data resolution. Community-based microbial source tracking (MST) offers new insight, but the bacterial communities could be affected by environmental fluctuations during the migration with sediments, which might induce instability of MST results. Therefore, the effects of environmental-induced community succession on the stability of MST were compared in this study. Liangxi River, a highly eutrophic urban river, was selected as the study area where sediment phosphorus sources are difficult to track because of multi-source pollution and complicated hydrodynamic conditions. Spearman correlation analysis (P < 0.05) was conducted to recognize a close relationship between sediment, bacterial communities and phosphorus, verifying the feasibility of MST for identify sediment phosphorus sources. Two distinct microbial community fingerprints were constructed based on whether excluded 113 vulnerable species, which were identified by analyzing the differences of microorganisms across a concentration gradient of exogenous phosphorus input in microbial environmental response experiment. Because of the lower unknown proportion and relative standard deviations, MST results were more stable and reliable when based on the fingerprints excluding species vulnerable to phosphorus. This study presents a novel insight on how to identify sediment phosphorus sources in multi-source polluted urban river, and would help to develop preferential control strategies for eutrophication management.

Functional characterization of a binding protein for Type-II sex pheromones in the tea geometrid moth Ectropis obliqua Prout.

The tea geometrid moth Ectropis obliqua Prout is one of the most serious moth pests in tea plants, and its sex pheromones have been identified as typical Type-II polyunsaturated hydrocarbons and epoxide derivatives. Therefore, the E. obliqua male olfactory system provides a good model to study the molecular basis of Type-II sex pheromone recognition as well as functional gene evolution towards structurally different types of moth sex pheromones. In this study, we identified the full-length sequence of a pheromone-binding protein, EoblPBP2 and revealed that it clustered together with the lepidopteran PBP2 subfamily, which binds Type I acetate pheromones. These findings suggest that the EoblPBP2 sequence and physiological function are conserved, although E. obliqua evolved Type II hydrocarbon and epoxide sex pheromones structurally different from Type I acetates. To examine this hypothesis, we studied the expression patterns and in vitro functions of EoblPBP2 in detail. Quantitative real-time PCR experiments showed that EoblPBP2 was predominantly expressed in male E. obliqua antennae. Fluorescence in situ hybridization further demonstrated that the EoblPBP2 gene was abundantly expressed in the pheromone-sensitive sensilla trichodea Str-I in male E. obliqua. The physiological function of recombinant EoblPBP2 was then examined using a competitive binding assay. The results showed that EoblPBP2 had high affinities for three E. obliqua Type II sex pheromone components and Type I acetate pheromones in comparison to some plant volatiles. These results indicate that PBP2 is involved in the detection of Type II pheromones in E. obliqua and it still retains high binding affinities to acetate pheromones and some green leaf ester volatiles.

Directed Graphene-Based Nanoplatforms for Hyperthermia: Overcoming Multiple Drug Resistance.

Multidrug resistance (MDR), which leads tumors resistance to traditional anticancer drugs, can cause the failure of chemotherapy treatments. Herein, we present a new way to overcome this problem using smart multifunctional graphene-based drug delivery systems which can target subcellular organelles and show synergistic hyperthermia and chemotherapy. Mitochondria-targeting ligands are conjugated onto the doxorubicin-loaded, polyglycerol-covered nanographene sheets to actively accumulate them inside the mitochondria after charge-mediated cellular internalization. Upon near-infrared (NIR) irradiation, adenosine triphosphate (ATP) synthesis and mitochondrial function were inhibited and doxorubicin released into the cellular interior. The hyperthermia-accelerated drug release led to a highly selective anticancer efficiency, confirmed by in vitro and in vivo experiments.

Chemical profiling of Jinqi Jiangtang tablets by HPLC-ESI-Q-TOF/MS.

AIM: To profile the chemical constituents in Jinqi Jiangtang tablets. METHOD: Based on the chromatographic retention behavior, fragmentation patterns of chemical components, and published literatures, a high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-Q-TOF/MS) method was established to characterize and identify components in Jinqi Jiangtang tablets. RESULTS: A total of 52 chemical compounds, including eight iridoid glycosides, seven phenolic acids, twelve alkaloids, six flavonoids, and nineteen saponins, were identified in Jinqi Jiangtang tablets. CONCLUSION: The established method could serve as a powerful tool for structural characterization and quality control of this Chinese herbal preparation.

Unbiased metabolite profiling by liquid chromatography-quadrupole time-of-flight mass spectrometry and multivariate data analysis for herbal authentication: classification of seven Lonicera species flower buds.

Plant-based medicines become increasingly popular over the world. Authentication of herbal raw materials is important to ensure their safety and efficacy. Some herbs belonging to closely related species but differing in medicinal properties are difficult to be identified because of similar morphological and microscopic characteristics. Chromatographic fingerprinting is an alternative method to distinguish them. Existing approaches do not allow a comprehensive analysis for herbal authentication. We have now developed a strategy consisting of (1) full metabolic profiling of herbal medicines by rapid resolution liquid chromatography (RRLC) combined with quadrupole time-of-flight mass spectrometry (QTOF MS), (2) global analysis of non-targeted compounds by molecular feature extraction algorithm, (3) multivariate statistical analysis for classification and prediction, and (4) marker compounds characterization. This approach has provided a fast and unbiased comparative multivariate analysis of the metabolite composition of 33-batch samples covering seven Lonicera species. Individual metabolic profiles are performed at the level of molecular fragments without prior structural assignment. In the entire set, the obtained classifier for seven Lonicera species flower buds showed good prediction performance and a total of 82 statistically different components were rapidly obtained by the strategy. The elemental compositions of discriminative metabolites were characterized by the accurate mass measurement of the pseudomolecular ions and their chemical types were assigned by the MS/MS spectra. The high-resolution, comprehensive and unbiased strategy for metabolite data analysis presented here is powerful and opens the new direction of authentication in herbal analysis.