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1.
ACS Macro Lett ; 11(4): 447-451, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35575316

RESUMO

The Diels-Alder reaction is striking as a prominent synthetic tool for the rapid construction of complex molecular frameworks, but the synthesis of porous organic polymers (POPs) via the Diels-Alder reaction is rare. Herein, we report the solvothermal synthesis of a new type of POPs (DA-POPs) via the furan/alkynyl Diels-Alder reaction. These polymers show favorable porous properties and high specific surface areas (up to 1041 m2·g-1). Meanwhile, the high porosity in conjuction of ether bridges in the DA-POPs enable a fine adsorption performance for the removal of Cr(VI) from aqueous solutions.

2.
J Environ Manage ; 315: 115150, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35489188

RESUMO

Metal-laden solid wastes (e.g., waste graphite powders) have attracted great attention owing to their hazardous effects on the surrounding soil and water. Additionally, the metal-bearing impurities also hinder the reutilization of waste graphite powders. Thus, it is necessary to remove these inorganic impurities and figure out the removal mechanism of impurities in the purification process. In this study, an alkaline roasting-water washing-acid leaching (AWA) method was used to upgrade the waste graphite powders, and the migration behavior of diverse impurities has been qualitatively and quantitatively investigated. A graphite product with high impurity removal efficiencies is attained under optimal conditions. The removal of impurities mainly follows three routes: (1) V-, P-, and S-bearing impurities were complete removed (some formed soluble salts during alkaline roasting, and the remainder was dissolved in acid); (2) most Al-, K-, and Si-bearing impurities were removed by alkaline roasting, with the remainder was dissolved in the acid-leaching process; and (3) Fe-, Mg-, Ti-, Ca-, and Zn-bearing impurities were decomposed at high temperature and reacted with alkali to form hydroxides or oxides, which was subsequently dissolved in acid. In addition, the treatment of the generated wastewater is also discussed. The uncovered migration mechanisms of diverse impurities would guide the purification and reutilization process of other metal-bearing solid wastes efficiently.

3.
ACS Nano ; 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35352548

RESUMO

Poly(ethylene glycol) (PEG) is the most widely used polymer to decorate inorganic nanoparticles (NPs) by the "grafting-to" method for antifouling properties. PEG also shows diverse supramolecular interactions with nanoparticle surfaces and polar molecules, suggesting that the physisorption between PEG chains and NPs cannot be ignored in the "grafting-to" process. However, the effect of physisorption of PEG to NPs on the process of chemisorption has been rarely studied. Herein, we report that unfunctionalized PEG is physically adsorbed on various NPs by polyvalent supramolecular interactions, adopting "loop-and-train-tail" conformations. We investigated the effect of molecular weight of PEG and ligands of the NPs on the conformation of PEG chains by experimental methods and simulation. It is demonstrated that the physisorption of PEG on NPs can facilitate the chemisorption in the initial stages but delays it in the later stages during the "grafting-to" process. This work provides a deeper understanding of the conformation of physisorbed PEG on NPs and the relationship between physisorption and chemisorption.

4.
Zhongguo Zhong Yao Za Zhi ; 47(4): 980-987, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35285198

RESUMO

The ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS~E) technology was employed to compare the chemical components between the aerial and underground parts of Coptis chinensis samples from different batches. According to the retention time, molecular ion peak, and LC-MS~E fragment information of the reference substances and available literature, we identified a total of 40 components. Thirty-three and 31 compounds were respectively identified in the underground part(taproots) and the aerial part(stems and leaves) of C. chinensis. Among them, 24 compounds, including alkaloids(e.g., berberine and jatrorrhizine) and phenolic acids(e.g., chlorogenic acid, quinic acid, and tanshinol), were common in the two parts. In addition, differential components were also identified, such as magnoline glucoside in the underground part and(±) lariciresionol-4-ß-D-glucopyranoside in the aerial part. The analysis of fragmentation pathways based on spectra of reference substances indicated the differences among samples of different batches. Furthermore, we performed the principal component analysis(PCA) for the peak areas of C. chinensis in different batches. The results showed that the underground part and the aerial part were clearly clustered into two groups, indicating that the chemical components contained in the two parts were different. Furthermore, the results of partial least squares discriminant analysis(PLS-DA) identified 31 differential compounds(VIP value>1) between the underground part and the aerial part, mainly including alkaloids, phenolic acids, lignans, and flavonoids. This study proves that C. chinensis possesses great development potential with multiple available compounds in stems and leaves. Moreover, it sheds light on for the development and utilization of non-medicinal organs of C. chinensis and other Chinese medicinal herbs.


Assuntos
Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Tecnologia
5.
Clin Neurophysiol ; 136: 206-218, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35217350

RESUMO

OBJECTIVE: Although working memory (WM) deficits are well-recognized core features of schizophrenia, the underlying pathophysiological substrates of impairment in early psychosis before medication remain unclear. One possibility is that deficits in selective attention contribute to WM impairment. METHODS: EEG was acquired from 25 first-episode drug-naive schizophrenia patients and 26 matched controls while they performed a WM task. RESULTS: Compared with controls, schizophrenia patients showed a deficit in WM capacity in both behavioral and electrophysiological measures. Notably, the increased parieto-occipital pre-encoding stimulus alpha power in patients with schizophrenia predicted their subsequent reduced N2pc and symptom severity, whereas this relationship was absent in controls. Moreover, lacking load effect in neural activities predicted the serious impairment in behavior for schizophrenia. CONCLUSIONS: This pilot study provides preliminary evidence that the lack of load effect in neural activities may serve as potential underlying mechanisms for the impaired selective attention and WM capacity in schizophrenia. Our results emphasize the importance of pre-encoding stimulus alpha power in first-episode drug-naive schizophrenia. SIGNIFICANCE: These findings provide a neurophysiological correlate for the subjective reports of working memory deficits in schizophrenia and indicate the potential effective targets for clinical intervention.


Assuntos
Memória de Curto Prazo , Esquizofrenia , Atenção , Humanos , Transtornos da Memória/etiologia , Memória de Curto Prazo/fisiologia , Projetos Piloto
6.
Antonie Van Leeuwenhoek ; 115(4): 473-486, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35119545

RESUMO

Two yellow-pigmented bacterial strains, LZ-14 T and ABI-LZ29, were isolated from the cultivable phycosphere microbiota of the highly toxic marine dinoflagellate Alexandrium catenella LZT09 and demonstrated obvious microalgae growth-promoting potentials toward the algal host. To elucidate the taxonomic status of the two bioactive bacterial strains, they were subjected to a polyphasic taxonomic characterization. Both strains were found to be Gram-negative, aerobic, rod-shaped and motile; to contain Q-10 as the predominant ubiquinone; summed feature 8, C16:0, C18:1 ω7c 11-methyl and summed feature 3 as the major fatty acids; and diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and two unidentified phospholipids as the predominant polar lipids. Based on the phylogenetic analysis, phylogenomic inferences and phenotypic characteristics, the strains could be clearly distinguished from phylogenetically closely related species and formed a distinct monophyletic lineage in the family Rhodobacteraceae. The size of the draft genome of strain LZ-14 T is 4.615 Mb, with a DNA G + C content of 63.3 mol%. It contains ten predicted secondary metabolite biosynthetic gene clusters and core genes for bacterial exopolysaccharide biosynthesis. Therefore, strain LZ-14 T (= CCTCC AB 2017230 T = KCTC 62342 T) represents a novel species of a new genus, for which the name Alexandriicola marinus gen. nov., sp. nov., is proposed.


Assuntos
Rhodobacteraceae , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/análise , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Análise de Sequência de DNA
7.
J Mater Chem B ; 10(7): 1077-1084, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35080577

RESUMO

Mechanical property mismatch between vascular patches and native blood vessels can result in post-operation failure; therefore, vascular patches that mimic the biomechanical properties of native blood vessels must be developed. In this study, we constructed a biomimetic vascular patch by coating a poly(ethylene glycol) (PEG) film onto a decellularized scaffold (DCS) and modifying its surface with a heparin-chitosan polyelectrolyte multilayer (PEM). The PEM-modified PEG/DCS vascular patches exhibited comparable mechanical characteristics with native blood vessels. They effectively resisted platelet adhesion, reduced the hemolysis rate, increased the clotting time in vitro, and favoured the adhesion and growth of endothelial progenitor cells. In addition, the modified patches maintained long-term patency (5 months) of the treated arteries in vivo. Because of the synergistic effect of heparin and chitosan in PEM, the vascular patches may be able to manage medical complications. Thus, the PEM-modified PEG/DCS vascular patches may have promising applications in the repair of damaged or diseased blood vessels.


Assuntos
Quitosana , Engenharia Tecidual , Animais , Biomimética , Quitosana/farmacologia , Heparina/farmacologia , Polieletrólitos , Polietilenoglicóis/farmacologia , Suínos
8.
Nat Prod Res ; 36(1): 26-36, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32375507

RESUMO

Five new lignans, euphorhirtins A-D (1-4), 5-methoxyvirgatusin (5), three artefacts, 7S-ethoxyisolintetralin (6), 7R-ethoxyisolintetralin (7), and 7R-ethoxy-3-methoxyisolintetralin (8), together with 13 known ones (9-21) were isolated from the medicinal plant Euphorbia hirta L. The structures of the compounds were elucidated by means of extensive spectroscopic analysis, including 1D and 2D NMR and HR-ESI-MS experiments. The absolute configurations of compound 1 was determined by ECD calculation. The isolates were evaluated for their inhibitory effects against the proliferation of the cancer cell lines (Hep G2, A549, and DU145) and compounds 14 and 18 showed inhibitory activity against the Hep G2 cells with IC50 values 7.2 ± 0.17 and 8.5 ± 0.36 µM.


Assuntos
Antineoplásicos Fitogênicos , Euphorbia , Lignanas , Células A549 , Antineoplásicos Fitogênicos/farmacologia , Euphorbia/química , Células Hep G2 , Humanos , Lignanas/farmacologia , Estrutura Molecular , Extratos Vegetais/farmacologia
9.
J Gastrointest Surg ; 25(12): 3033-3039, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34668164

RESUMO

PURPOSE: The magnetic compression technique (MCT) is a new surgical method that has been used for gastrointestinal anastomosis, choledochojejunostomy, and intestinal anastomosis, but there are no reports on its use for esophagogastric anastomosis. This study aimed to investigate the feasibility of using MCT to fashion esophagogastric anastomoses in rabbits. METHODS: Twenty rabbits were randomized into an MCT group (study group, n = 10) and a hand-sewn group (control group, n = 10). The magnetic compression anastomosis device used in this study was made of neodymium iron boron (NdFeB) and possessed parent (PMR) and daughter (DMR) magnetic rings. To fashion the anastomosis, the PMR and DMR were inserted into the lower esophagus and gastric fundus, respectively. The coupled magnets automatically compressed the sandwiched tissues and were expelled once the anastomosis was installed. The two groups were further compared in terms of the anastomosis construction time, survival rate, and postoperative complications. One month after the anastomosis was installed, the burst pressure and gross appearance of the anastomoses were evaluated. RESULTS: The anastomosis construction time in the study group was significantly shorter than that in the control group (10.50 ± 1.58 min vs. 18.60 ± 2.22 min; P < 0.05), and the magnetic rings were defecated out in 10.70 ± 3.49 days. The incidence of anastomotic blockage in both the study and control groups did not differ significantly (0%, 0/10 vs. 20%, 2/10; P > 0.05). Anastomotic leakage was not found in either of the groups, and the anastomoses burst pressures were similar in the two groups. However, the magnetically compressed anastomoses in the study group had a relatively smoother gross appearance than the hand-sewn anastomoses. CONCLUSION: The magnetic compression anastomosis device is a safe and feasible tool for fashioning esophagogastric anastomoses in this animal model.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Magnetismo , Anastomose Cirúrgica , Animais , Fenômenos Magnéticos , Imãs , Coelhos
10.
Zhongguo Zhong Yao Za Zhi ; 46(12): 2900-2911, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467680

RESUMO

Paridis Rhizoma(PR) is prepared from the dried rhizome of Paris polyphylla var. yunnanensis(PPY) or P. polyphylla var. chinensis(PPC) in Liliaceae family. The rapid development of PPY or PPC planting industry resulted from resource shortage has caused the waste of a large number of non-medicinal resources. To clarify the chemical compositions in rhizomes, fibrous roots, stems, leaves, seeds and pericarps of PPC, and explore the comprehensive application value and development prospect of these parts, the qualitative and quantitative analyses on the different parts of PPC were carried out by ultra-high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS/MS) and high performance liquid chromatography(HPLC). A total of 136 compounds were identified, including 112 steroidal saponins, 6 flavonoids, 11 nitrogen-containing compounds and 7 phytosterols. Rhizomes, fibrous roots, and seeds mainly contained protopennogenyl glycosides and pennogenyl glycosides; leaves and stems mainly contained protodiosgenyl glycosides and diosgenyl glycosides; pericarps mainly contained pennogenyl glycosides, followed by diosgenyl glycosides. The total level of four saponins was the highest in fibrous roots and rhizomes, followed by those in the pericarps and arillate seeds, and the lowest in the stems and exarillate seeds. This study can provide data support for the comprehensive development and rational application of non-medicinal parts of PPC.


Assuntos
Liliaceae , Melanthiaceae , Saponinas , Cromatografia Líquida de Alta Pressão , Rizoma , Espectrometria de Massas em Tandem
11.
Zhongguo Zhong Yao Za Zhi ; 46(12): 2912-2922, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467681

RESUMO

The dried fruit body of Phylloporia ribis(Hymenochaetaceae), which prefers to live on the stumps of Lonicera japonica(Caprifoliaceae), has a variety of activities, whereas its pharmacodynamic material basis is not completely clear and there are few reports on its quality control and evaluation. In this study, an UPLC-Q-TOF-MS method was used to analyze the nucleosides and nucleobases in P. ribis and a HPLC method was established for simultaneous determination of 10 nucleosides and nucleobases. MS and MS/MS data were acquired in positive ion mode. Based on the data comparison of the sample and the reference substance, the literature data and the compound databases of ChemSpider and PubChem, 18 nucleosides and nucleobases were identified qualitatively from the water extract of P. ribis for the first time. After optimization, the HPLC was performed using a Welch Ultimate AQ C_(18) column(4.6 mm×250 mm, 5 µm) by gradient elution with acetonitrile and water as mobile phase, the flow rate of 1.0 mL·min~(-1), the detection wavelength of 260 nm, and the column temperature of 30 ℃. Through the investigation of the extraction method, solvent and time, it was determined that the test solution should be obtained by cold water extraction for 18 h. At the present HPLC conditions, 10 components of uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine and thymidine could be well separated(R > 1.5) and showed good linearity(r > 0.999 9) in the concentration ranges of 0.247-24.7, 0.283-28.3, 0.273-27.3, 0.256-25.6, 0.257-25.7, 0.318-31.8, 0.245-24.5, 0.267-26.7, 0.250-25.0 and 0.267-26.7 mg·L~(-1), respectively. The average reco-veries of 10 components were 95.78%-104.5%, and the RSDs were 2.2%-5.2%(n=6). The contents of 10 nucleosides and nucleobases in different samples of P. ribis varied greatly, which were 0.021-0.122, 0.004-0.029, 0.014-0.226, 0.009-0.442, 0.003-0.014, 0.002-0.146, 0.007-0.098, 0-0.054, 0.005-0.069, 0.004-0.081 and 0.072-1.28 mg·g~(-1) for uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine, thymidine and total 10 components, respectively. These results demonstrated that the components had significant differences in the internal quality, and good quality control was needed to ensure the medical efficacy. This study provides a scientific basis for the discovery of pharmacodynamic ingredients, quality control and evaluation of P. ribis.


Assuntos
Nucleosídeos , Espectrometria de Massas em Tandem , Basidiomycota , Cromatografia Líquida de Alta Pressão , Guanosina
12.
Zhongguo Zhong Yao Za Zhi ; 46(12): 2931-2941, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467683

RESUMO

As a new strategy capable of uncovering the characteristics of traditional Chinese medicines, the quantitative analysis of multi-components by single-marker(QAMS) has been widely employed for the quality evaluation of Chinese medicinal materials, slices, and extracts. However, its application in the assessment of Chinese patent medicines is yet to be explored. By referring to the determination of three bufogenins in Bufonis Venenum by QAMS described in Chinese Pharmacopoeia(2020 Edition), this paper selected seven representative preparations containing Bufonis Venenum and explored whether the relative correction factors(RCFs) of cinobufagin(CB) to bufalin(BF) and resibufogenin(RB) could be directly used for the quality control of Bufonis Venenum-contained preparations. Based on the qualitative analyses under the same chromatographic conditions as used for toad venom, combing specificity test, five preparations such as Yatong Yili Pills, Houzheng Pills, Xiongdan Jiuxin Pills, Liushen Pills and Niuhuang Xiaoyan Pills, were expected to use validated RCFs for the direct determination of three components. Taking Houzheng Pills as an example, the methodological validation of bufalin, cinobufagin and resibufogenin was carried out, and the recoveries of bufalin, cinobufagin and resibufogenin were 90.64%-106.1%. The obvious difference was not observed between the contents of bufalin and resibufogenin in 24 batches of preparation samples by QAMS and external reference method. In the tested samples, the content of bufalin, cinobufagin and resibufogenin were 1.27-2.61, 2.44-5.66 and 0.988-3.16 mg·g~(-1) in 10 batches of Liushen Pills samples. The contents of bufalin, cinobufagin and resibufogenin were 0.760-1.32, 1.35-2.39 and 0.600-1.55 mg·g~(-1) in 10 batches of Houzheng Pills samples from three manufacturers. The obtained data contribute to improving the quality standard of Bufonis Venenum-contained preparations, and they also provide some ideas for the application of QAMS in the quality evaluation and control of Chinese patent medicines.


Assuntos
Medicina Tradicional Chinesa , Medicamentos sem Prescrição , China , Cromatografia Líquida de Alta Pressão , Controle de Qualidade
13.
Zhongguo Zhong Yao Za Zhi ; 46(12): 2889-2899, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467710

RESUMO

Sophorae Flavescentis Radix,derived from the root of Sophora flavescens in the Leguminosae family,has been widely used in the medicine,agriculture,animal husbandry,and daily chemical industry. A pharmacophore model-based method for rapid discovery of tyrosinase inhibitors( TIs) from S. flavescens was established by molecular docking under Lipinski rules,and verified by enzyme assays. Briefly,the chemical constituent database of S. flavescens( CDSF) was established based on the previous papers. Theoptimal pharmacophore model( OPM) was constructed by DS 2019 on the basis of known active TIs. Eighty-three hits predominated by flavonoids having higher fitting scores with OPM than the positive control were screened out,and subjected to molecular docking based on the three-dimensional structure of tyrosinase crystal protein. The potential TIs such as kurarinone and nor-kurarinone were rapidly discovered from the compounds with higher docking scores than the positive control under the Lipinski rules. The results were verified by the in vitro enzyme assays. The inhibition activities of tyrosinase from non-medicinal parts of S. flavescens were also tested to explore the relationship between the inhibition activity and chemical compositions. This study is expected to provide data support for the comprehensive application and development of S. flavescens and also a new method for the rapid discovery of active substances or functional constituents in the complex systems.


Assuntos
Sophora , Animais , Flavonoides , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase , Extratos Vegetais/farmacologia , Raízes de Plantas
14.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4023-4033, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467711

RESUMO

Paris polyphylla var. chinensis(PPC) is used as one of the origin plants of Paridis Rhizoma described in the Chinese Pharmacopoeia(2020 edition). Its resources shortage makes the planting scale gradually expand, and plenty of aerial parts are abandoned because of not being effectively used. On the basis of previous research, this study separated steroidal saponins to further clarify the chemical composition of the aerial parts of PPC. As a result, three pairs of 25R or 25S epimers of furostanol saponins were obtained by various column chromatography techniques. Their structures were identified as neosolanigroside Y6(1), solanigroside Y6(2), neoprotogracillin(3), protogracillin(4), neoprotodioscin(5) and protodioscin(6) by spectral data combining with chemical transformation. Compound 1 is a new compound, and compounds 2, 3 and 5 are isolated from Paris plants for the first time. Compounds 4 and 6 are isolated from this plant for the first time. Previously, only several spirostanol glycosides with 25S configuration were isolated from Paris plants. Guided by mass spectrometry, the present study isolated the furostanol saponins with 25S configuration from this genus for the first time, which further enriches the chemical information of Paris genus and provides a reference for the isolation of similar compounds.


Assuntos
Liliaceae , Melanthiaceae , Saponinas , Extratos Vegetais , Rizoma
15.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4040-4050, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467713

RESUMO

In recent years, the establishment of the commercial grade of Yinpian [traditional Chinese medicine(TCM) pieces for decoction] in the TCM industry has been hotly disputed. In this article, Sophorae Flavescentis Radix(SFR) was selected as a representative example to investigated. Through systematic comparison and analysis, the different grades of SFR slices were traced, verified and evaluated. According to the current published local grade standards of SFR slices, the results showed that the first-class of SFR slices were mostly derived from the wild medicinal materials, the second-class were mostly originated from the cultivated materials in 3-4 years, and the third-class products were from a small number of lateral roots and short-growing years or harsh habitat of wild medicinal materials. On the basis of identifying the sources of different grades of SFR slices, the contents of the active components, including matrine, oxymatrine, oxysophocarpine, sophoridine, N-methyl-cytisine, sophocarpine, were quantitatively determined in typical samples, it was found that the grades were inversely proportional to the contents of active ingredients. In order to ensure the universality of the conclusion, the contents of different grades of commercial SFR slices were determined, and the conclusion was verified as "the commercial grades of SFR slices were inversely linked to their contents of active ingredients". This phenomenon is common in the determination of the commercial grade of Yinpian of radix and rhizome. Therefore, we propose that the method or standard of the commercial grade of Yinpian of radix and rhizome based on the size of Yinpian maybe not proper. Whether and how to classify Yinpian commercial grade is not only a multi-disciplinary issue, especially in combination with clinical efficacy, but also a big problem need to consider the production, commercial circulation and other processes link of quality risk and quality assurance, and should be treated with great caution.


Assuntos
Medicamentos de Ervas Chinesas , Sophora , Medicina Tradicional Chinesa , Raízes de Plantas , Rizoma
16.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4051-4060, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467714

RESUMO

This research established the HPLC methods for the determination of perillaketone, perillaldehyde, caffeic acid, scutellarin, and rosmarinic acid in 33 batches of Perillae Folium. Kromasil C_(18)(4.6 × 250 mm, 5 µm) chromatographic column was used, and the mobile phase for determination of the perillaketone and perillaldehyde was methanol-water(55∶45) solution, at a flow rate of 1.0 mL·min~(-1), with the column temperature at 30 ℃. The mobile phase for the determination of caffeic acid, scutellarin and rosmarinic acid was methanol(A)-0.2% phosphoric acid aqueous solution(B) with gradient elution(0-20 min, 25%-30% A; 20-60 min, 30%-43% A). The flow rate was 1.0 mL·min~(-1) and the column temperature was set at 30 ℃. The results showed that the established method can achieve good separation of the five components in samples, with a good linear relationship and high accuracy, indicating that the methods can be used for the determination of Perillae Folium. The results showed that all samples contained five components. And the content of rosmarinic acid(0.04%-1.57%) > scutellarin(0.03%-0.77%) > perillaldehyde(0.02%-0.66%) > perillaketone(0.03%-0.30%) > caffeic acid(0.006%-0.07%). Thirty-three Batches of Perillae Folium can be grouped into 5 categories. There are certain content rules and region specificities under different clusters. Perillaketone, perillaldehyde, and rosmarinic acid can be used as the main markers to evaluate the quality of Perillae Folium.


Assuntos
Medicamentos de Ervas Chinesas , Folhas de Planta , Cromatografia Líquida de Alta Pressão , Extratos Vegetais
17.
Antonie Van Leeuwenhoek ; 114(12): 2003-2017, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34532778

RESUMO

A novel actinobacterium NJES-13T was isolated from the gut of Antarctic emperor penguin Aptenodytes forsteri. The new isolate produces bioactive gephyromycin metabolites and exopolysaccharides (EPS). Cells were Gram-negative, motile with the peritrichous flagella, and with a faint layer of extracellular slime. Colonies were yellow when grown on marine agar, ISP1, 2, 4 and TSA media. The strain developed clusters of coccoid, and divided by binary fission in the early phase of growth. The cell clusters were gradually disrupted during the stationary phase and formed short rod-shape cells which were interconnected by viscous EPS showing a three-dimensional net-like morphology, and contained polyhydroxyalkanoates (PHA) granules inside the cells. Growth of strain NJES-13T was observed at 15-45 °C, at pH 6.0-9.0 with 0.5-9.0% (w/v) NaCl. The complete genomic size of strain NJES-13T was 3.45 Mb with a DNA G + C content of 67.0 mol%. The combined polyphasic taxonomic characterizations presented in this study unequivocally separated strain NJES-13T from all known genera in the family Dermatophilaceae. Thus, strain NJES-13T represents a novel species of a new genus, for which the name Gephyromycinifex aptenodytis gen. nov., and sp. nov. is proposed. The type strain is NJES-13T (= CCTCC 2019007T = KCTC 49281T). Genetic prediction of secondary metabolite biosynthesis revealed a 44.5 kb-long biosynthetic gene cluster (BGC) of type III polyketide synthase (PKS) as well as four other BGCs, indicating its great potential to produce novel bioactive metabolites derived from the gut microbiota of animals living in the extreme habitats in the Antarctica.


Assuntos
Spheniscidae , Animais , Regiões Antárticas , Técnicas de Tipagem Bacteriana , DNA Bacteriano , Ácidos Graxos/análise , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA
18.
Mar Drugs ; 19(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34436297

RESUMO

A new versatile actinobacterium designated as strain NJES-13 was isolated from the feces of the Antarctic emperor penguin. This new isolate was found to produce two active gephyromycin analogues and bioflocculanting exopolysaccharides (EPS) metabolites. Phylogenetic analysis based on pairwise comparison of 16S rRNA gene sequences showed that strain NJES-13 was closely related to Mobilicoccus pelagius Aji5-31T with a gene similarity of 95.9%, which was lower than the threshold value (98.65%) for novel species delineation. Additional phylogenomic calculations of the average nucleotide identity (ANI, 75.9-79.1%), average amino acid identity (AAI, 52.4-66.9%) and digital DNA-DNA hybridization (dDDH, 18.6-21.9%), along with the constructed phylogenomic tree based on the up-to-date bacterial core gene (UBCG) set from the bacterial genomes, unequivocally separated strain NJES-13 from its close relatives within the family Dermatophilaceae. Hence, it clearly indicated that strain NJES-13 represented a putative new actinobacterial species isolated from the gut microbiota of mammals inhabiting the Antarctic. The obtained complete genome of strain NJES-13 consisted of a circular 3.45 Mb chromosome with a DNA G+C content of 67.0 mol%. Furthering genome mining of strain NJES-13 showed the presence of five biosynthetic gene clusters (BGCs) including one type III PKS responsible for the biosynthesis of the core of gephyromycins, and a series of genes encoding for bacterial EPS biosynthesis. Thus, based on the combined phylogenetic and active metabolites characterization presented in this study, we confidently conclude that strain NJES-13 is a novel, fresh actinobacterial candidate to produce active gephyromycins and microbial bioflocculanting EPS, with potential pharmaceutical, environmental and biotechnological implications.


Assuntos
Actinobacteria/genética , Antraquinonas/metabolismo , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Spheniscidae , Animais , Regiões Antárticas , Organismos Aquáticos , Técnicas de Tipagem Bacteriana , Fezes/microbiologia , Humanos , Filogenia , Fitoterapia , RNA Ribossômico 16S/genética
19.
J Chem Phys ; 154(18): 184903, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34241008

RESUMO

The composition and structure of a membrane determine its functionality and practical application. We study the supramolecular polymeric membrane prepared by supramolecular emulsion interfacial polymerization (SEIP) on the oil-in-water droplet via the computer simulation method. The factors that may influence its structure and properties are investigated, such as the degree of polymerization and molecular weight distribution (MWD) of products in the polymeric membranes. We find that the SEIP can lead to a higher total degree of polymerization as compared to the supramolecular interfacial polymerization (SIP). However, the average chain length of products in the SEIP is lower than that of the SIP due to its obvious interface curvature. The stoichiometric ratio of reactants in two phases will affect the MWD of the products, which further affects the performance of the membranes in practical applications, such as drug release rate and permeability. Besides, the MWD of the product by SEIP obviously deviates from the Flory distribution as a consequence of the curvature of reaction interface. In addition, we obtain the MWD for the emulsions whose size distribution conforms to the Gaussian distribution so that the MWD may be predicted according to the corresponding emulsion size distribution. This study helps us to better understand the controlling factors that may affect the structure and properties of supramolecular polymeric membranes by SEIP.

20.
Environ Pollut ; 288: 117765, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34265558

RESUMO

Artificial light at night has been proposed as a global threat to biodiversity. Insectivorous bats are strictly nocturnal animals that are vulnerable to disruption from artificial light. Given that many light-sensitive bats tend to avoid night light during roost departure, it is often assumed that nighttime light pollution reduces their foraging opportunities, albeit empirical evidence in support of this hypothesis remains elusive. Here, we used least horseshoe bats, Rhinolophus pusillus, to assess whether white artificial light is detrimental for the opportunities of foraging. We manipulated the levels of ambient illumination and perceived predation risk inside the bat roost. We monitored bats' emergence activity using high-speed video and audio recording systems. DNA-based faecal dietary analysis and insect survey were applied to determine activity time of prey in foraging areas. Following experimentally manipulation of white light-emitting diode (LED) lighting 0-15 min after sunset, bat pass, flight duration, and echolocation pulse emission decreased. The mean emergence time of bats flying out was delayed by 14 min under lit treatment compared with the dark control. Only 10% of bats left for foraging during 40 min of light exposure. Aversive effects of LED light on bat emergence were robust regardless of the presence of a potential predator. Insect prey reached a peak of abundance between 30 and 60 min after sunset. These results demonstrate that white artificial light hinders evening emergence behavior in least horseshoe bats, leading to a mismatch between foraging onset and peak food availability. Our findings highlight that light pollution overrides foraging onset, suggesting the importance of improving artificial lighting scheme near the roosts of light-sensitive bats.


Assuntos
Quirópteros , Mariposas , Animais , Dieta , Insetos , Comportamento Predatório
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