Messenger RNA (mRNA) has broad potential for application in biological systems. However, one fundamental limitation to its use is its relatively short half-life in biological systems. Here we develop ...exogenous circular RNA (circRNA) to extend the duration of protein expression from full-length RNA messages. First, we engineer a self-splicing intron to efficiently circularize a wide range of RNAs up to 5 kb in length in vitro by rationally designing ubiquitous accessory sequences that aid in splicing. We maximize translation of functional protein from these circRNAs in eukaryotic cells, and we find that engineered circRNA purified by high performance liquid chromatography displays exceptional protein production qualities in terms of both quantity of protein produced and stability of production. This study pioneers the use of exogenous circRNA for robust and stable protein expression in eukaryotic cells and demonstrates that circRNA is a promising alternative to linear mRNA.
Ziziphi spinosae semen has been widely used to treat insomnia and anxiety. To profile its chemical components, an online comprehensive two‐dimensional liquid chromatography‐mass spectrometry was ...developed. In this two‐dimensional liquid chromatography system, a novel phthalic anhydride‐bonded stationary phase column was combined with a C18 column. As a result, this new stationary phase exhibited remarkable differences in separation selectivity from C18, achieving a good orthogonality of 83.3%. Moreover, this new stationary phase with weaker hydrophobicity than C18 realized solvent compatibility in the online configuration. Coupled with tandem MS, 154 compounds were identified, including 51 unreported compounds. Compared with one‐dimensional liquid chromatography‐mass spectrometry, this online two‐dimensional liquid chromatography‐mass spectrometry system exhibited a much higher resolving power in isomer separation. This work provided an effective separation and characterization method for the material basis of Ziziphi spinosae semen. This strategy provides ideas for the material basis research of other traditional Chinese medicines.
Perilla (Perilla frutescens, PF) is an annual labiaceae herb that can be used as vegetable, seasoner, and herb, which mainly includes red PF (P. frutescens var. crispa) and green PF (P. frutescens ...var. frutescens). Red and green Perilla is mainly used for medicine and food, respectively. In order to explore the differences between these two Perilla cultivars and the effects of origin on them, we studied the components of 130 Perilla samples from different origins by ultra‐high performance liquid chromatography quadrupole‐time‐of‐flight mass spectrometry combined with partial least squares discriminant analysis and orthogonal partial least squares discriminant analysis. In this study, 57 potential compounds were analyzed, mainly including organic acids, flavonoids, terpenoids, and anthocyanins. In different varieties of Perilla, anthocyanins were found only in red PF. In addition, the content of four flavonoids, two organic acids, and one coumarin in red PF is much higher than that in green PF. Among the same variety of Perilla, the contents of three metabolites were higher in the north of China for red Perilla, while five metabolites were higher in the south of China for green Perilla. Overall, this research provided a basis for distinguishing different varieties and sources of Perilla through the differential metabolites of Perilla.
Background
Dietary changes are suggested to play a role in the increasing prevalence of allergic diseases and asthma. Short‐chain fatty acids (SCFAs) are metabolites present in certain foods and are ...produced by microbes in the gut following fermentation of fibers. SCFAs have been shown to have anti‐inflammatory properties in animal models. Our objective was to investigate the potential role of SCFAs in the prevention of allergy and asthma.
Methods
We analyzed SCFA levels by high‐performance liquid chromatography (HPLC) in fecal samples from 301 one‐year‐old children from a birth cohort and examined their association with early life exposures, especially diet, and allergy and asthma later in life. Data on exposures and allergic diseases were collected by questionnaires. In addition, we treated mice with SCFAs to examine their effect on allergic airway inflammation.
Results
Significant associations between the levels of SCFAs and the infant's diet were identified. Children with the highest levels of butyrate and propionate (≥95th percentile) in feces at the age of one year had significantly less atopic sensitization and were less likely to have asthma between 3 and 6 years. Children with the highest levels of butyrate were also less likely to have a reported diagnosis of food allergy or allergic rhinitis. Oral administration of SCFAs to mice significantly reduced the severity of allergic airway inflammation.
Conclusion
Our results suggest that strategies to increase SCFA levels could be a new dietary preventive option for allergic diseases in children.
Children with high levels of butyrate or propionate in feces at one year of age have significantly less atopic sensitization compared to children with lower levels.
The infant's diet might influence the levels of SCFAs.
Oral application of short‐chain fatty acids might protect children against the development of atopic sensitization and airway inflammation.
Commercial solutions of pesticides consist of two main components: The active substance and the formulation ingredients. These ingredients, mainly composed of polymeric surfactants, are considered ...inert vis‐à‐vis the targeted organisms and nature. Nonetheless, a relatively low attention is given to their analysis and fate tracking in the environment. In this context, the current paper, embedded in a large study of fate and impact of formulated pesticides in soil, focuses on the analysis of these formulation ingredients. It mainly highlights and discusses the characteristic response of these ingredients in liquid chromatography–mass spectrometry‐based untargeted screening of two commercial herbicides applied on soil. This characteristic response is based on different spectral and chromatographic aspects, as their amplified adducts and double‐charged ions formation, or their “wavy” chromatographic profiles and the inversion of their elution order following the polymerization degree. These patterns are briefly discussed in order to explain them, and then thanks to their understanding, 12 different series (165 compounds) of formulation ingredients were outlined and discriminated from active substance and soil metabolites. After, high‐resolution and tandem mass spectrometry data were investigated for rapid interseries and intraseries identification‐by‐chain. In addition, recommendations for methods development and hints on postanalytical data processing for identity determination of these ingredients are given in order to help in enhancing future studies. Limitations of the applied approach are also outlined, and some innovate suggestions are provided based on the described findings.
Lag Ba’Omer, a nationwide bonfire festival in Israel, was chosen as a case study to investigate the influence of a major biomass burning event on the light absorption properties of atmospheric brown ...carbon (BrC). The chemical composition and optical properties of BrC chromophores were investigated using a high performance liquid chromatography (HPLC) platform coupled to photo diode array (PDA) and high resolution mass spectrometry (HRMS) detectors. Substantial increase of BrC light absorption coefficient was observed during the night-long biomass burning event. Most chromophores observed during the event were attributed to nitroaromatic compounds (NAC), comprising 28 elemental formulas of at least 63 structural isomers. The NAC, in combination, accounted for 50–80% of the total visible light absorption (>400 nm) by solvent extractable BrC. The results highlight that NAC, in particular nitrophenols, are important light absorption contributors of biomass burning organic aerosol (BBOA), suggesting that night time chemistry of •NO3 and N2O5 with particles may play a significant role in atmospheric transformations of BrC. Nitrophenols and related compounds were especially important chromophores of BBOA. The absorption spectra of the BrC chromophores are influenced by the extraction solvent and solution pH, implying that the aerosol acidity is an important factor controlling the light absorption properties of BrC.
Curcumin is a safe substance that is used as food cosmetic additive and pharmaceutical product. Obtaining pure curcumin from plant sources is very important for fundamental research as well as for ...the above applications. Efficient extraction and purification methods, which meet green chemistry criteria including safety, environment-friendliness, economic requirements, and process efficiency are needed.
This review provides an up-to-date and comprehensive summary of the various methods used for extraction and purification of curcumin from plant materials, and its various applications in food, cosmetics and pharmaceutical fields.
Many different extraction methods ranging from conventional techniques (e.g. soxhlet extraction, maceration and solvent extraction) to advanced extraction technologies (e.g. ultrasound-assisted extraction, microwave-assisted extraction, enzyme-assisted extraction, supercritical liquid extraction, etc.) have been exploited to obtain curcumin from plant materials. Various other substances co-exist with curcumin in crude extracts. Many different purification techniques, alone or in combination, have been investigated for isolation and purification of curcumin from curcumin extracts or commercially available crude curcumin. These include conventional techniques (e.g. column chromatography, semi-preparative high performance liquid chromatography) and supplementary modern techniques (e.g. high-speed counter-current chromatography, supercritical fluid chromatography). To recover curcumin from plant materials, selection of apposite routes based on novel technologies (both in extraction and purification) is important to maximize efficiency, to decrease use of toxic solvent, as well as to reduce the processing time and energy consumption. Additionally, various potential or commercial uses of curcumin are reviewed.
•Curcumin is a safe bioactive substance used in food, cosmetics and pharmaceutical industries.•Conventional and advanced techniques for curcumin extraction and purification are discussed.•The advantages and disadvantages of various extraction and separation methods are outlined.•Applications of curcumin in different industries are summarized.
Endemic in 21 countries, Chagas disease, also known as American Trypanosomiasis, is a neglected tropical disease (NTD) caused by the protozoan parasite Trypanosoma cruzi. The available drugs for the ...treatment of this disease, benznidazole and nifurtimox, are outdated and display severe side effects. Thus, the discovery of new drugs is crucial. Based on our continuous studies aiming towards the discovery of natural products with anti-T. cruzi potential, the MeOH extract from aerial parts of Baccharis sphenophylla Dusén ex. Malme (Asteraceae) displayed activity against this parasite and was subjected to high-performance countercurrent chromatography (HPCCC), to obtain one unreported syn-labdane diterpene — sphenophyllol (1) — as well as the known compounds gaudichaudol C (2), ent-kaurenoic acid (3), hispidulin (4), eupafolin (5), and one mixture of di-O-caffeoylquinic acids (6–8). Compounds 1–8 were characterized by analysis of nuclear magnetic resonance (NMR) and mass spectrometry (MS) data. When tested against trypomastigote forms, isolated labdane diterpenes 1 and 2 displayed potent activity, with ECsub.50 values of 20.1 μM and 2.9 μM, respectively. The mixture of chlorogenic acids 6–8, as well as the isolated flavones 4 and 5, showed significant activity against the clinically relevant amastigotes, with ECsub.50 values of 24.9, 12.8, and 2.7 μM, respectively. Nonetheless, tested compounds 1–8 displayed no cytotoxicity against mammalian cells (CCsub.50 > 200 μM). These results demonstrate the application of HPCCC as an important tool to isolate bioactive compounds from natural sources, including the antitrypanosomal extract from B. sphenophylla, allowing for the development of novel strategic molecular prototypes against tropical neglected diseases.
Ultra-high-performance liquid chromatography high-resolution mass spectrometry (UHPLC-HRMS) variants currently represent the best tools to tackle the challenges of complexity and lack of ...comprehensive coverage of the metabolome. UHPLC offers flexible and efficient separation coupled with high-sensitivity detection via HRMS, allowing for the detection and identification of a broad range of metabolites. Here we discuss current common strategies for UHPLC-HRMS-based metabolomics, with a focus on expanding metabolome coverage.
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