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Anionic carbonate CO3− has been found in interstellar space and the Martian atmosphere, but its production mechanism is in debate so far. To mimic the irradiation-induced reactions on icy micrograins in the Martian atmosphere and the icy shell of interstellar dust, here we report a laboratory investigation on the dissociative electron attachments to the molecular clusters of CO2. We find that anionic species (CO2)n−1O− and (CO2)n− (n = 2, 3, 4) are produced in the concerted reaction and further stabilized by the evaporative cooling after the electron attachment. We further propose a dynamics model to elucidate their competitive productions: the (CO2)n− yields survive substantially in the molecular evaporative cooling at the lower electron attachment energy, while the reactions leading to (CO2)n−1O− are favored at the higher attachment energy. This work provides new insights into physicochemical processes in CO2-rich atmospheres and interstellar space. [ABSTRACT FROM AUTHOR]

A resonant system consisting of an excess electron and a closed-shell atom or molecule, as a temporary negative ion, is usually in doublet-spin states that are analogous to bright states of photoexcitation of the neutral. However, anionic higher-spin states, noted as dark states, are scarcely accessed. Here, we report the dissociation dynamics of CO− in dark quartet resonant states that are formed by electron attachments to electronically excited CO (a3Π). Among the dissociations to O−(2P) + C(3P), O−(2P) + C(1D), and O−(2P) + C(1S), the latter two are spin-forbidden in the quartet-spin resonant states of CO−, while the first process is preferred in 4Σ− and 4Π states. The present finding sheds new light on anionic dark states. [ABSTRACT FROM AUTHOR]

In recent years, caffeic acid and its derivatives have received increasing attention due to their obvious physiological activities and wide distribution in nature. In this paper, to clarify the status of research on plant-derived caffeic acid and its derivatives, nuclear magnetic resonance spectroscopy data and possible biosynthetic pathways of these compounds were collected from scientific databases (SciFinder, PubMed and China Knowledge). According to different types of substituents, 17 caffeic acid and its derivatives can be divided into the following classes: caffeoyl ester derivatives, caffeyltartaric acid, caffeic acid amide derivatives, caffeoyl shikimic acid, caffeoyl quinic acid, caffeoyl danshens and caffeoyl glycoside. Generalization of their 13C-NMR and 1H-NMR data revealed that acylation with caffeic acid to form esters involves acylation shifts, which increase the chemical shift values of the corresponding carbons and decrease the chemical shift values of the corresponding carbons of caffeoyl. Once the hydroxyl group is ester, the hydrogen signal connected to the same carbon shifts to the low field (1.1~1.6). The biosynthetic pathways were summarized, and it was found that caffeic acid and its derivatives are first synthesized in plants through the shikimic acid pathway, in which phenylalanine is deaminated to cinnamic acid and then transformed into caffeic acid and its derivatives. The purpose of this review is to provide a reference for further research on the rapid structural identification and biofabrication of caffeic acid and its derivatives. [ABSTRACT FROM AUTHOR]

Medicinal and edible homologs (MEHs) can be used in medicine and food. The National Health Commission announced that a total of 103 kinds of medicinal and edible homologous plants (MEHPs) would be available by were available in 2023. Diabetes mellitus (DM) has become the third most common chronic metabolic disease that seriously threatens human health worldwide. Polysaccharides, the main component isolated from MEHPs, have significant antidiabetic effects with few side effects. Based on a literature search, this paper summarizes the preparation methods, structural characterization, and antidiabetic functions and mechanisms of MEHPs polysaccharides (MEHPPs). Specifically, MEHPPs mainly regulate PI3K/Akt, AMPK, cAMP/PKA, Nrf2/Keap1, NF-κB, MAPK and other signaling pathways to promote insulin secretion and release, improve glycolipid metabolism, inhibit the inflammatory response, decrease oxidative stress and regulate intestinal flora. Among them, 16 kinds of MEHPPs were found to have obvious anti-diabetic effects. This article reviews the prevention and treatment of diabetes and its complications by MEHPPs and provides a basis for the development of safe and effective MEHPP-derived health products and new drugs to prevent and treat diabetes. • Distinctive structure of MEHPPs biomacromolecules governs their properties. • MEHPPs have anti-diabetic effects significantly with few side effects. • The potential anti-diabetic mechanism of MEHPPs is elucidated. • Prospects and limitations of MEHPPs anti-diabetic are discussed. [ABSTRACT FROM AUTHOR]

The prebiotic mechanism to produce molecular oxygen (O2) in carbon dioxide (CO2)-rich planetary atmospheres is of great importance in understanding astrochemical reactions and is potentially relevant to the origin of life on Earth. Here, we demonstrate that, aside from the direct productions of O2 by photodissociation and dissociative electron attachment, the low-energy ion-molecule reaction between cationic helium in solar winds and molecular CO2 is a noticeable mechanism. Branching ratios of the reaction channels are determined, and their absolute cross-sections are estimated accordingly. The present findings represent a further, indispensable step towards fully understanding the origins of atmospheric O2. The abiotic production of molecular oxygen in carbon dioxide-rich planetary atmospheres is important in understanding astrochemical reactions and potentially the origin of life on Earth. Here, the authors demonstrate that the low-energy reaction between helium ions, as found in solar winds, and carbon dioxide produces molecular oxygen. [ABSTRACT FROM AUTHOR]

According to ancient literature, Prunella vulgaris L. (P vulgaris) alleviates mastitis and has been used in China for many years; however, there are no relevant reports that confirm this or the mechanism of its efficacy. To explore the anti-acute mastitis effect and potential mechanism of P vulgaris extract. First, the active ingredients and targets of P vulgaris against mastitis were predicted using network pharmacology. Next, the relevant active ingredients were enriched using macroporous resins and verified using UV and UPLC-Q-TOF-MS/MS. Lastly, a mouse model of acute mastitis was established by injecting lipopolysaccharides into the mammary gland and administering P vulgaris extract by oral gavage. The pathological changes in mammary tissue were observed by HE staining. Serum and tissue inflammatory factors were measured by ELISA method. MPO activity in mammary tissue was measured using colorimetry and MPO expression was detected by immunohistochemistry. The expression of tight junction proteins (ZO-1, claudin-3, and occludin) in mammary tissue was detected by immunofluorescence and Western blot. iNOS and COX-2 in mammary tissue were detected by Western blot. MAPK pathway and NF-κB pathway related proteins were also detected by Western blot. Network pharmacology predicted that phenolic acids and flavonoids in P vulgaris had anti-mastitis effects. The contents of total flavonoids and total phenolic acids in P vulgaris extract were 64.5% and 29.4%, respectively. UPLC-Q-TOF-MS/MS confirmed that P vulgaris extract contained phenolic acids and flavonoids. The results of animal experiments showed that P vulgaris extract reduced lipopolysaccharide-induced inflammatory edema, inflammatory cell infiltration, and interstitial congestion of mammary tissue. It also reduced the levels of serum and tissue inflammatory factors TNF-α, IL-6, and IL-1β, and inhibited the activation of MPO. Furthermore, it downregulated the expression of MAPK and NF-κB pathway-related proteins. The expressions of ZO-1, occludin, and claudin-3 in mammary gland tissues were upregulated. P vulgaris extract can maintain the integrity of mammary connective tissue and reduce its inflammatory response to prevent acute mastitis. Its mechanism probably involves regulating NF-κB and MAPK pathways. [Display omitted] • Phenolic acids and flavonoids in P vulgaris may be effective ingredients of Prunella vulgaris L for anti-mastitis. • Experimental evidence supports P vulgaris as a potential remedy for acute mastitis. • UPLC-Q-TOF-MS/MS confirms phenolic acids and flavonoids in P vulgaris extract. • P vulgaris extract can improve the inflammatory reaction in the mammary gland tissue. [ABSTRACT FROM AUTHOR]

Prunella vulgaris L. (P. vulgaris , Labiatae) is a perennial medicinal and edible plant widely used in China, Korea, Japan and Europe. The reddish brown spica of P. vulgaris (Prunellae Spica), which is collected in summer, has been commonly used in traditional medicine and food industry, while it is also used with whole grass in Europe and Taiwan. To clarify the regulatory pathways and mechanism of quality formation in P. vulgaris , targeted metabolomic, transcriptomic, and proteomic analyses of Prunellae Spica samples from five consecutive developmental stages were carried out. The results showed that terpenoids were mainly synthesized in the maturity stage of Prunellae Spica, with the key enzymes and coding genes in downstream pathways being mainly expressed during ripening, while related enzymes in the upstream pathway showed the opposite pattern. Flavonoids mainly accumulated before ripening, with highly expressed pathway enzymes and coding genes. The accumulation of phenylpropanoids was relatively active throughout the development process. Rosmarinic acid (RA) and its synthetic intermediate products mainly accumulated via more active pathway enzymes and coding genes before ripening. The regulatory factors and metabolites related to RA synthesis were mainly enriched in phenylpropanoid biosynthesis, plant hormone signal transduction, plant pathogen interaction, oxidative phosphorylation, and endoplasmic reticulum protein processing pathways. [Display omitted] [ABSTRACT FROM AUTHOR]

We had successfully fabricated CuInSe 2 (CIS) thin film by electro-deposition technique. Electro-deposited ternary selenide precursor was thermally annealed under nitrogen conditions to form CuInSe 2 films. The structure, composition, chemical state and optical characterization of CuInSe 2 films were measured using several techniques, including Scanning electron microscopy (SEM), Atomic force microscopy (AFM), Atomic emission spectroscopy (AES), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Ultraviolet Spectrophotometry (UV) and electrochemical workstation. The results showed that the CuInSe 2 thin films formed using electro-deposition had dense grain structure whose size was various with the increase of the deposited voltage and annealing temperature. The band gap of CuInSe 2 was 1.43 eV when deposition voltage was 1.7 V, and CIS film exhibited the most excellent property. [ABSTRACT FROM AUTHOR]

The work is focused on electroless nickel plating on polyimide film. The Ni salt activation, which neglects the use of palladium, is adopted in pretreatment. The orthogonal experiment and single factor test are used to optimize the experiment, thus the optimum compositions and conditions of electroless nickel plating are obtained. The cleaned, activated and deposited polyimide films are also characterized by their structure, morphology, component and chemical state. The activation process of nickel salt is analyzed on basis of experiment and test. A Ni–P film with fine and dense structure is achieved on the polyimide film which consists of 92.23 wt.% Ni and 7.77 wt.% P. The result of tensile test indicates that the adhesion between the substrate and the coating layer is sufficiently excellent due to dimples by etching. [ABSTRACT FROM AUTHOR]

Prunella vulgaris L., better known as 'self-heal', has been extensively used in the traditional system of medicines. To reveal the regulatory mechanism of its development, TMT-based quantitative proteome analysis was performed in the Prunella vulgaris L. spica before and during ripening (Group A and Group B, respectively). This analysis resulted in the identification of 7655 proteins, of which 1910 showed differential abundance between the two groups. Pronounced changes in the proteomic profile included the following: 1) Stress-responsive proteins involved in protecting cells and promoting fruit ripening and seed development were highly abundant during ripening. 2) The degradation of chlorophyll, inhibition of chlorophyll biosynthesis and increased abundance of transketolase occurred simultaneously in the spica of Prunella vulgaris L., resulting in the spica changing color from green to brownish red. 3) The abundance of protein species related to phenylpropanoid biosynthesis mainly increased during ripening, while flavonoid and terpenoid backbone biosynthesis mostly occurred before ripening. This study establishes a link between protein profiles and mature phenotypes, which will help to improve our understanding of the molecular mechanisms involved in the maturation of Prunella vulgaris L. at the proteome level and reveal the scientific connotation for the best time to harvest Prunella vulgaris L. This work provides a scientific basis for the production of high-quality medicinal Prunella vulgaris L., as well as a typical demonstration of molecular research used for the harvest period of traditional Chinese medicine. This work provided a comprehensive overview on the functional protein profile changes of Prunella vulgaris L. spica at different growing stages, as well as the scientific rationale of Prunella vulgaris L. harvested in summer after brownish red, thus laid an intriguing stepping stone for elucidating the molecular mechanisms of quality development. Unlabelled Image • Prunella vulgaris L. spica was sampled at five developmental stages (from heading to physiological maturity). • LC-MS matched 7655 proteins, of which 6405 can be quantified and 1910 proteins showed differences in abundance. • High abundance of stress-responsive protein species involved in fruit maturity and seed development during spica ripening. • The up-representation of transketolase, the degradation and inhibition synthesis of chlorophyll cause the spica changing color. • Increased levels of protein related to phenylpropanoid biosynthesis were observed during spica ripening [ABSTRACT FROM AUTHOR]