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https://www.readbyqxmd.com/read/29244753/identification-of-a-multicomponent-traditional-herbal-medicine-by-hplc-ms-and-electron-and-light-microscopy
#1
Ju-Han Liu, Yung-Yi Cheng, Chen-Hsi Hsieh, Tung-Hu Tsai
BACKGROUND: Commercial pharmaceutical herbal products have enabled people to take traditional Chinese medicine (TCM) in a convenient and accessible form. However, the quantity and quality should be additionally inspected. To address the issue, a combination of chemical and physical inspection methods were developed to evaluate the amount of an herbal formula, Xiang-Sha-Liu-Jun-Zi-Tang (XSLJZT), in clinical TCM practice. METHODS: A high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS) method with electrospray ionization was developed to measure the herbal biomarkers of guanosine, atractylenolide III, glycyrrhizic acid, dehydrocostus lactone, hesperidin, and oleanolic acid from XSLJZT...
December 15, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29244495/antiprotozoal-sesquiterpene-lactones-and-other-constituents-from-tarchonanthus-camphoratus-and-schkuhria-pinnata
#2
Njogu M Kimani, Josphat C Matasyoh, Marcel Kaiser, Reto Brun, Thomas J Schmidt
In continuation of a search for new antiprotozoal agents from plants of the family Asteraceae, Tarchonanthus camphoratus and Schkuhria pinnata have been investigated. By following the promising in vitro activity of the dichloromethane extracts from their aerial parts, bioassay-guided chromatographic isolation yielded two known sesquiterpene lactones (1 and 2) from T. camphoratus and 20 known compounds of this type from S. pinnata. From the latter, a new eudesmanolide, (1R*,5S*,6R*,7R*,8R*,10R*)-1-hydroxy-8-[5″-hydroxy-4'-(2″-hydroxyisovaleroyloxy)tigloyloxy]-3-oxoeudesma-11(13)-en-6,12-olide (3), and two new germacranolides, 3β-(2″-hydroxyisovaleroyloxy)-8β-(3-furoyloxy)costunolide (14) and 1(10)-epoxy-3β-hydroxy-8β-[5'-hydroxy-4'-(2″-hydroxyisovaleroyloxy)tigloyloxy]costunolide (16), were obtained...
December 15, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/29243431/-sesquiterpenes-with-anti-metastasis-breast-cancer-activity-from-chloranthus-henryi
#3
Shan-Shan Zhang, Jian-Jiang Fu, Huai-Yuan Chen, Lin-Feng Tu, Chun-Rong Xiao, Rui-Zeng Zhang, Ding-Ping Liu, Yong-Ming Luo
To study sesquiterpenes with anti-metastasis breast cancer activity from Chloranthus henryi, ten sesquiterpenes ,zedoarofuran (1), chlorajapolide D (2), 4β, 8β-dihydroxy-5α(H)-eudesm-7(11)-en-8, 12-olide (3), curcolonol (4), lasianthuslactone A (5), chlomultin C (6), (1E,4Z)-8-hydroxy-6-oxogermacra-1(10), 4, 7(11) -trieno-12, 8-lactone (7), shizukanolide E (8) , shizukanolide F (9) , 9α-hydroxycurcolonol (10), and five bis-sesquiterpenes, shizukaol B (11), shizukaol C (12) , cycloshizukaol A (13) , sarcandrolide B (14) , henriol A(15), were isolated by using different kinds of column chromatography methods from the ethyl acetate part of Ch...
October 2017: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
https://www.readbyqxmd.com/read/29240866/pityriasis-folliculorum-response-to-topical-ivermectin
#4
Kavita Darji, Nicole M Burkemper
<p>Pityriasis folliculorum has been described as a dry type of rosacea with extensive proliferation of Demodex folliculorum in pilosebaceous follicles of the skin. This skin condition is frequently difficult to manage, with various treatment options showing mixed efficacy. Oral ivermectin, a macrocyclic lactone parasiticide with anti-inflammatory and anti-parasitic effects, is one of the leading treatment modalities for demodicosis. Topical ivermectin has recently been FDA approved as therapy for rosacea...
December 1, 2017: Journal of Drugs in Dermatology: JDD
https://www.readbyqxmd.com/read/29239615/direct-activation-of-%C3%AE-sp3-carbons-of-saturated-carboxylic-esters-as-electrophilic-carbons-via-oxidative-carbene-catalysis
#5
Bin Liu, Weihong Wang, Ruoyan Huang, Jiekuan Yan, Jichang Wu, Wei Xue, Song Yang, Zhichao Jin, Yonggui Robin Chi
An N-heterocyclic carbene-catalyzed oxidative LUMO activation of the β-cabons of saturated carboxylic esters is disclosed. This approach allows for efficient asymmetric access to lactams and lactones by directly installing functional groups to the typically inert β-sp3 carbons of saturated esters. The use of HOBt as an additive was found to significantly improve both yields and enantioselectivities of the reactions.
December 14, 2017: Organic Letters
https://www.readbyqxmd.com/read/29237378/substrates-for-paraoxonase
#6
Xiaojing Mu, Xiaoqi Yi, Shangyou Xiao, Chengshan Wang, Gang Chen, Yan Li
BACKGROUND: Paraoxonase (PON) is a family of calcium-dependent hydrolases which is related to many diseases. Elucidation of PON physiological roles, active center and all applications in medical fields are dependent of its substrates. OBJECTIVE: The reports about PON substrates scattered in a long span of period are collected to afford clue for drug design, diagnosis of PON status and other academic purposes. METHOD: PON substrates from 134 references are classified and compared...
December 12, 2017: Current Pharmaceutical Design
https://www.readbyqxmd.com/read/29236332/a-new-mechanism-for-%C3%AE-lactamases-class-d-enzymes-degrade-1%C3%AE-methyl-carbapenems-via-lactone-formation
#7
Christopher T Lohans, Emma van Groesen, Kiran Kumar, Catherine L Tooke, James Spencer, Robert S Paton, Jürgen Brem, Christopher Schofield
β-Lactamases threaten the clinical use of carbapenems, considered antibiotics of last resort. The classical mechanism of serine carbapenemase activity proceeds via hydrolysis of an acyl-enzyme intermediate. We show that class D β-lactamases also degrade clinically used 1β-methyl-substituted carbapenems via the unprecedented formation of a carbapenem-derived β-lactone. β-Lactone formation results from the nucleophilic attack of the carbapenem hydroxyethyl side chain onto the ester carbonyl of the acyl-enzyme intermediate...
December 13, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/29236117/liquid-crystal-elastomer-foams-with-elastic-properties-specifically-engineered-as-biodegradable-brain-tissue-scaffolds
#8
M E Prévôt, H Andro, S L M Alexander, S Ustunel, C Zhu, Z Nikolov, S T Rafferty, M T Brannum, B Kinsel, L T J Korley, E J Freeman, J A McDonough, R J Clements, E Hegmann
Tissue regeneration requires 3-dimensional (3D) smart materials as scaffolds to promote transport of nutrients. To mimic mechanical properties of extracellular matrices, biocompatible polymers have been widely studied and a diverse range of 3D scaffolds have been produced. We propose the use of responsive polymeric materials to create dynamic substrates for cell culture, which goes beyond designing only a physical static 3D scaffold. Here, we demonstrated that lactone- and lactide-based star block-copolymers (SBCs), where a liquid crystal (LC) moiety has been attached as a side-group, can be crosslinked to obtain Liquid Crystal Elastomers (LCEs) with a porous architecture using a salt-leaching method to promote cell infiltration...
December 13, 2017: Soft Matter
https://www.readbyqxmd.com/read/29234729/a-comprehensive-study-of-eco-friendly-natural-pigment-and-its-applications
#9
Ramendra Singh Parmar, Charu Singh
Actinomycetes, a large group of filamentous bacteria account for 70-80% of secondary metabolites available commercially. The present investigation was undertaken with an aim to identify and characterize pigment from actinomycetes. Actinomycetes were isolated from rhizosphere soil samples collected from different regions of Madhya Pradesh state. Out of 85 actinomycetes, only 5 actinomycetes showed pigment production and based on diffusible pigment production ability one actinomycete ARITM02 was selected. The extraction of pigment was done by solvent extraction method using methanol and purified by TLC and column chromatography...
March 2018: Biochemistry and Biophysics Reports
https://www.readbyqxmd.com/read/29234552/differentiation-between-3-4-and-4-15-epoxyeudesmanolides-by-electrospray-ionization-tandem-mass-spectrometry
#10
Herbert Júnior Dias, Ricardo Stefani, José Carlos Tomaz, Ricardo Vessecchi, Antônio Eduardo Miller Crotti
We investigated the fragmentation of the eudesmanolide-type sesquiterpene lactones 1α-(4-hydroxymethacryloyloxy)-3α,4α-epoxy-8α-hydroxyeudesm-11(13)-6α,12-olide (1) and 1α-(2,3-epoxyangeloyloxy)-4α,15-epoxy-8α-hydroxyeudesm-11(13)-6α,12-olide (2) by electrospray ionization tandem mass spectrometry (ESI-MS/MS). The elimination of the different ester substituent at C(1) directly from protonated 1 and 2 (A) led to the formation of two regioisomer product ions B (A - RCO2H). Further fragmentation of B resulted from consecutive eliminations of H2O and CO molecules...
2017: Journal of Analytical Methods in Chemistry
https://www.readbyqxmd.com/read/29232953/mitochondrial-signs-and-subcellular-imaging-imply-the-antifungal-mechanism-of-carabrone-against-gaeumannomyces-graminis-var-tritici
#11
Lanying Wang, Yunfei Zhang, Delong Wang, Mei Wang, Yong Wang, Juntao Feng
Carabrone, a botanical bicyclic sesquiterpenic lactone, has broad-spectrum antifungal activities, and is particularly efficient against the devastating phytopathogen Gaeumannomyces graminis var.tritici (Ggt). The antifungal mechanism of carabrone against Ggt, however, remains unclear. The main objective of this study was to investigate the subcellular localization of carabrone in Ggt to make a better understanding of the mechanism of action. When Ggt was exposed to carabrone (EC50 value, 28.45 μg/mL) for 7 days, the decline of mitochondrial concentration, together with some obvious alternations in the mitochondrial structure including hazy outline, medullary transition, excess accumulation of unclear settlings, and vacuolar degeneration were observed, indicating that carbrone may act on the mitochondria directly...
December 12, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29232752/simultaneous-determination-of-rosuvastatin-rosuvastatin-5%C3%A2-s-lactone-and-n-desmethyl-rosuvastatin-in-human-plasma-by-uplc-ms-ms-and-its-application-to-clinical-study
#12
Xue Bai, Xi-Pei Wang, Guo-Dong He, Bin Zhang, Min Huang, Jia-Li Li, Shi-Long Zhong
Objective A rapid and sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) assay was developed and validated for the simultaneous quantification of rosuvastatin (RST), rosuvastatin-5 S-lactone (RSTL), and N-desmethyl rosuvastatin (DM-RST) in human plasma. Methods Sample was prepared by liquid-liquid extraction with ethyl acetate from 100 μL acidulated buffered plasma. Then analytes were chromatographically separated using an Acquity UPLC HSS T3 column (3.0 mm×100 mm, 1...
December 12, 2017: Drug Research
https://www.readbyqxmd.com/read/29231719/clay-catalyzed-disruption-of-quorum-sensing-in-vibrio-harveyi-bacteria
#13
Sajo Naik, Jonathon Scholin, San Ching, Fang Chi, Marc Herpfer
This work describes clay catalyzed degradation of N- (3-Oxooctanoyl)-DL-homoserine lactone, a quorum sensing (QS) molecule that Gram negative bacteria employ during the QS process. The disruption of QS by clay in Gram-negative Vibrio harveyi bacterium culture was also studied by monitoring luminescence and population density of the bacteria.
December 12, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29231144/qsar-of-natural-sesquiterpene-lactones-as-inhibitors-of-myb-dependent-gene-expression
#14
Gloria Castellano, Lucia Redondo, Francisco Torrens
Protein c-Myb is a therapeutic target. Some sesquiterpene lactones suppress Myb-dependent gene expression, which results in a mechanism for their potential anti-cancer activity. Database ChEMBL is representative of lactones for physicochemical and physiochemical properties. Data presented for 31 natural lactones are discussed in terms of quantitative structure-activity relationships, which objective is to predict inhibitors of Myb-induced gene expression. Several constitutional descriptors are related to structure-activity...
December 11, 2017: Current Topics in Medicinal Chemistry
https://www.readbyqxmd.com/read/29227651/total-syntheses-of-scaparvins-b-c-and-d-enabled-by-a-key-c-h-functionalization
#15
Qinda Ye, Pei Qu, Scott A Snyder
The clerodane diterpene family possesses an impressive range of bioactivities and high synthetic challenge due to their unique amalgamation of rings, stereocenters, and oxygenation. Herein, we disclose the first total syntheses of three members, scaparvins B, C, and D, through a route fueled by several chemoselective and carefully orchestrated steps. One such operation is a tailored late-stage C-H functionalization converting a carboxylic acid into a lactone through the oxidation of a tertiary C-H bond under conditions that minimize epoxidation of an alkene...
December 11, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/29225430/insights-from-the-molecular-dynamics-simulation-of-bcsd-subunit-from-k-xylinus
#16
Simranjit Kaur, Mahesh Kulharia
Biofilms are bacteria living in micro-colonies with a protective coating in sessile form. The biofilm protects bacteria from harsh surroundings as well as help in antibiotics resistance using a semi-fluid substance. Cellulose is the major component of biofilm, which provides the sticky appearance to bacteria for attaching to the substratum. The bacteria communicate in biofilm with the help of quorum sensing hormones Acylated Homoserine Lactones (AHL's). In Komagataeibacter xylinus the four genes Bcs A, Bcs B, Bcs C, Bcs D are associated with cellulose biosynthesis...
2017: Bioinformation
https://www.readbyqxmd.com/read/29223921/metabolism-and-pharmacokinetics-of-alantolactone-and-isoalantolactone-in-rats-thiol-conjugation-as-a-potential-metabolic-pathway
#17
Bailun Zhou, Ji Ye, Niao Yang, Liping Chen, Zhiguo Zhuo, Ling Mao, Qun Liu, Gongcai Lan, Jing Ning, Guangbo Ge, Ling Yang, Yunheng Shen, Shumei Wang, Weidong Zhang
Alantolactone (AL) and isoalantolactone (IAL), two major active sesquiterpene lactones isolated from Radix Inulae extract, have a wide range of pharmacological activities. The predominant metabolic pathway of AL and IAL observed was glutathione (GSH) conjugation in vitro, which could occur in the absence of metabolic enzymes. Non-enzymatic conjugation with cysteine (Cys) couldalso be observed. Four metabolites (AL-GSH, AL-Cys, IAL-GSH, IAL-Cys) were subsequently isolated and confirmed by nuclear magnetic resonance (NMR)...
December 2, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29223568/n-3-oxododecanoyl-l-homoserine-lactone-a-quorum-sensing-molecule-affects-cellular-content-of-nonprotein-thiol-content-in-rat-lymphocytes-its-relation-with-intracellular-zn2
#18
Yumiko Nishimura-Danjobara, Keisuke Oyama, Kaori Kanemaru, Keiko Takahashi, Kumio Yokoigawa, Yasuo Oyama
Cellular actions of N-(3-oxododecanoyl)-l-homoserine-lactone (ODHL), a quorum sensing molecule of bacteria, were studied on rat thymocytes using a flow cytometer with appropriate fluorescent dyes to elucidate the effects of ODHL on host cells. A bell-shaped concentration-response relation was observed in the ODHL-induced changes in cellular glutathione content ([GSH]i). ODHL concentration-dependently increased intracellular Zn2+ levels ([Zn2+]i) and cellular O2- content ([O2-]i). The bell-shaped relation induced by ODHL can be explained as follows: a low concentration of ODHL is expected to induce moderate oxidative stress that intracellularly releases Zn2+ by converting thiols to disulfides...
December 6, 2017: Chemico-biological Interactions
https://www.readbyqxmd.com/read/29222099/isolation-of-the-pinoresinol-mineralizing-pseudomonas-sp-sg-ms2-and-elucidation-of-its-catabolic-pathway
#19
Madhura Shettigar, Sahil Balotra, David Cahill, Andrew C Warden, Michael J Lacey, Hans-Peter E Kohler, Daniel Rentsch, John G Oakeshott, Gunjan Pandey
Pinoresinol is a dimer of two β-β' linked coniferyl alcohol molecules. It is both a plant defence molecule synthesized from the shikimic acid pathway and a representative of several β-β linked dimers produced during the microbial degradation of lignin in dead plant material. Until now little has been known about the bacterial catabolism of such dimers. Here we report the isolation of an efficient (+)-pinoresinol mineralizing Pseudomonas sp. strain SG-MS2 and its catabolic pathway. Degradation of pinoresinol in this strain is inducible and proceeds via a novel oxidative route which is in contrast to the previously reported reductive transformation by other bacteria...
December 8, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/29219311/multicomponent-enantioselective-michael-michael-aldol-%C3%AE-lactonizations-delivering-complex-%C3%AE-lactones
#20
Khoi N Van, Daniel Romo
Optically active, tertiary amine Lewis bases react with unsaturated acid chlorides to deliver chiral, α, β-unsaturated acylammonium salts. These intermediates participate in a catalytic, enantioselective, three-component process delivering bi- and tricyclic β-lactones through a Michael-Michael-aldol-β-lactonization. In a single operation, the described multicomponent, organocascade process forms complex bi- and tri-cyclic β-lactones by generating four new bonds, two rings and up to four contiguous stereocenters...
December 8, 2017: Journal of Organic Chemistry
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