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https://www.readbyqxmd.com/read/28538667/impact-of-maturity-of-malay-cherry-lepisanthes-alata-leaves-on-the-inhibitory-activity-of-starch-hydrolases
#1
Yan Zhang, Yuyang Gui, Dejian Huang
Aqueous extracts of young (7-day-old) Malay cherry (Lepisanthes alata) leaves were incorporated into wheat and rice flours to evaluate their inhibitory activities against α-amylase and α-glucosidase. HPLC-ESI/MS² results showed that the active components in young leaves were proanthocyanidins with lower mean degrees of polymerisation (≤10). The IC50 of the aqueous extracts of young leaves were 2.50 ± 0.03 and 12.91 ± 0.29 µg/mL, against α-amylase and α-glucosidase, which make them less active compared to the mature leaves...
May 24, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28535597/variation-and-accumulation-patterns-of-poly-and-perfluoroalkyl-substances-pfas-in-european-perch-perca-fluviatilis-across-a-gradient-of-pristine-swedish-lakes
#2
Staffan Åkerblom, Nesrin Negm, Pianpian Wu, Kevin Bishop, Lutz Ahrens
This study assessed variations in the concentrations of poly- and perfluoroalkyl substances (PFAS) in European perch (Perca fluviatilis) in Swedish lakes and the extent to which fish size, age and indicators of fish trophic ecology (δ(15)N and δ(13)C) correlate with the sum of individual PFAS concentrations (ΣPFAS). Fish muscle tissue samples (n=80) were taken from six lakes across Sweden and analysed using solid-liquid extraction followed by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS)...
May 19, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28535423/chromatographic-separation-and-detection-methods-of-aloe-arborescens-miller-constituents-a-systematic-review
#3
REVIEW
Jilan A Nazeam, Haidy A Gad, Hala M El-Hefnawy, Abdel-Naser B Singab
Aloe arborescens Miller (Family Asphodelaceae) is a member of genus Aloe, which is used in traditional medicine to cure various diseases. The extracts of the plant have been reported to possess anticancer, immunomodulator, antidiabetic, anti-inflammatory and antioxidant activities. The phytochemical investigations have revealed diverse chemical constituents, including phenolics [anthraquinones, anthrones, pyrones, chromones and coumarins], polysaccharides [arborans [(1-4) linked glucomannans, polysaccharide (A, B and C): (A: a linear (1-6)-O-α-glucan, B: a branching (1-2)-O-l-arabinose with (1-2)-O-d-galactose linkages and C: (1-4)-O-β-mannan with 18% acetyl group)]], glycoproteins and carboxypeptidase enzyme...
April 29, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28535345/natural-predominance-of-abscisic-acid-in-pongammia-pinnata-karanj-honey-contributed-to-its-strong-antimutagenicity
#4
Sudhanshu Saxena, Jyoti Tripathi, Suchandra Chatterjee, Satyendra Gautam
Various samples of raw (unprocessed) floral honey collected from different geographical locations of India were assayed for its antimutagenicity against ethyl methanesulfonate in E. coli MG1655 cells through rifampicin resistance assay. A monofloral honey ('Pongammia pinnata', local name 'Karanj') displayed maximum antimutagenicity (78.0 ± 1.7; P≤0.05). Solid phase extraction (using amberlite XAD-2 resin) followed by HPLC resulted into different peaks displaying varying antimutagenicity. Peak at retention time (Rt) 27...
May 23, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28534807/lobophorin-k-a-new-natural-product-with-cytotoxic-activity-produced-by-streptomyces-sp-m-207-associated-with-the-deep-sea-coral-lophelia-pertusa
#5
Alfredo F Braña, Aida Sarmiento-Vizcaíno, Miguel Osset, Ignacio Pérez-Victoria, Jesús Martín, Nuria de Pedro, Mercedes de la Cruz, Caridad Díaz, Francisca Vicente, Fernando Reyes, Luis A García, Gloria Blanco
The present article describes the isolation of a new natural product of the lobophorin family, designated as lobophorin K (1), from cultures of the marine actinobacteria Streptomyces sp. M-207, previously isolated from the cold-water coral Lophelia pertusa collected at 1800 m depth during an expedition to the submarine Avilés Canyon. Its structure was determined using a combination of spectroscopic techniques, mainly ESI-TOF MS and 1D and 2D NMR. This new natural product displayed cytotoxic activity against two human tumor cell lines, such as pancreatic carcinoma (MiaPaca-2) and breast adenocarcinoma (MCF-7)...
May 19, 2017: Marine Drugs
https://www.readbyqxmd.com/read/28531830/isotope-coded-derivatization-based-lc-esi-ms-ms-methods-using-a-pair-of-novel-reagents-for-quantification-of-hydroxycinnamic-acids-and-hydroxybenzoic-acids-in-fermented-brown-rice-product
#6
Shoujiro Ogawa, Kiriko Takafuji, Sumi Tsubuku, Yukiko Horie, Shigeo Ikegawa, Tatsuya Higashi
Hydroxycinnamic acids (HCAs) and hydroxybenzoic acids (HBAs) are antioxidant phytochemicals found in rice and effective for the prevention of human diseases including cancer. FBRA, which is a functional food manufactured by fermenting brown rice and rice bran with Aspergillus oryzae, has been demonstrated to have chemopreventive effects against carcinogenesis in various organs. In this study, we developed methods for the relative and absolute quantification of ferulic acid, sinapic acid, caffeic acid, protocatechuic acid and syringic acid in the FBRA and raw material (RM; unfermented brown rice and rice bran) samples by LC/ESI-MS/MS combined with derivatization using a newly developed reagent, N-(2-aminoethyl)-4-(diethylamino)benzamide (ADB) and its deuterium-coded analog, d-ADB...
May 2, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28530588/capillary-electrophoresis-coupled-to-mass-spectrometry-employing-hexafluoro-2-propanol-for-the-determination-of-nucleosides-and-nucleotide-mono-di-and-tri-phosphates-in-baby-foods
#7
María Mateos-Vivas, Javier Domínguez-Álvarez, Encarnación Rodríguez-Gonzalo, Rita Carabias-Martínez
The present work describes a method for the simultaneous determination of unmodified nucleosides and nucleotide mono-, di- and tri-phosphates by capillary electrophoresis coupled to mass spectrometry (CE-MS). The use of hexafluoro-2-propanol (HFIP) in the separation medium, and as an additive to the sheath liquid of the electrospray interface (ESI), generated a highly efficient and sensitive method. Instrumental limits of detection in the range of 14-53ngmL(-1) for nucleosides and 7-23, 20-49 and 64-124ngmL(-1) for nucleotide mono-, di-, and tri-phosphates, respectively, were found...
October 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28527513/enzymatic-biosynthesis-of-novel-neobavaisoflavone-glucosides-via-bacillus-udp-glycosyltransferase
#8
Tao Ma, Yi-Qun Dai, Nan Li, Qiang Huo, Hong-Mei Li, Yu-Xin Zhang, Zheng-Hao Piao, Cheng-Zhu Wu
The present study was designed to perform structural modifications of of neobavaisoflavone (NBIF), using an in vitro enzymatic glycosylation reaction, in order to improve its water-solubility. Two novel glucosides of NBIF were obtained from an enzymatic glycosylation by UDP-glycosyltransferase. The glycosylated products were elucidated by LC-MS, HR-ESI-MS, and NMR analysis. The HPLC peaks were integrated and the concentrations in sample solutions were calculated. The MTT assay was used to detect the cytotoxic activity of compounds in cancer cell lines...
April 2017: Chinese Journal of Natural Medicines
https://www.readbyqxmd.com/read/28525277/hydrolyzable-tannins-flavonol-glycosides-and-phenolic-acids-show-seasonal-and-ontogenic-variation-in-geranium-sylvaticum
#9
Anu Tuominen, Juha-Pekka Salminen
The seasonal variation of polyphenols in the aboveground organs and roots of Geranium sylvaticum in four populations was studied using UPLC-DAD-ESI-QqQ-MS/MS. The content of the main compound, geraniin, was the highest (16% of dry weight) in the basal leaves after the flowering period but stayed rather constant throughout the growing season. The compound-specific mass spectrometric methods revealed the different seasonal patterns in minor polyphenols. The maximum content of galloyl glucoses and flavonol glycosides were detected in the small leaves in May...
May 19, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28524082/cellular-repair-of-dna-dna-cross-links-induced-by-1-2-3-4-diepoxybutane
#10
Lisa N Chesner, Amanda Degner, Dewakar Sangaraju, Shira Yomtoubian, Susith Wickramaratne, Bhaskar Malayappan, Natalia Tretyakova, Colin Campbell
Xenobiotic-induced interstrand DNA-DNA cross-links (ICL) interfere with transcription and replication and can be converted to toxic DNA double strand breaks. In this work, we investigated cellular responses to 1,4-bis-(guan-7-yl)-2,3-butanediol (bis-N7G-BD) cross-links induced by 1,2,3,4-diepoxybutane (DEB). High pressure liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI⁺-MS/MS) assays were used to quantify the formation and repair of bis-N7G-BD cross-links in wild-type Chinese hamster lung fibroblasts (V79) and the corresponding isogenic clones V-H1 and V-H4, deficient in the XPD and FANCA genes, respectively...
May 18, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28523846/a-novel-rapid-analysis-using-mass-spectrometry-to-evaluate-downstream-refolding-of-recombinant-human-insulin-like-growth-factor-1-mecasermin
#11
Kenichiro Furuki, Toshimasa Toyo'oka, Hideto Yamaguchi
RATIONALE: Mecasermin is used to treat elevated blood sugar as well as growth hormone-resistant Laron-type dwarfism. Mecasermin isolated from inclusion bodies in extracts of E.coli must be refolded to acquire sufficient activity. However, there is no rapid analytical method for monitoring refolding during the purification process. METHODS: We prepared mecasermin drug product, in-process samples during the oxidation of mecasermin, forced-reduced mecasermin, and aerially oxidized mecasermin after forced reduction...
May 19, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28523113/human-serum-albumin-delivered-au-pet3-is-a-potent-inhibitor-of-t-cell-proliferation
#12
Tyler C Dean, Mu Yang, Mingyong Liu, Jason M Grayson, Anthony W DeMartino, Cynthia S Day, Jingyun Lee, Cristina M Furdui, Ulrich Bierbach
Using a modular library format in conjunction with cell viability (MTS) and flow cytometry assays, 90 cationic complexes [AuPL] (n+) (P = phosphine ligand; L = thiourea derivative or chloride) were studied for their antiproliferative activity in CD8(+) T lymphocyte cells. The activity of the compounds correlates with the steric bulk of the phosphine ligands. Thiourea serves as a leaving group that is readily replaced by cysteine thiol (NMR, ESI-MS). Taking advantage of selective thiourea ligand exchange, the fragments [Au(PEt3)](+) and [Au(JohnPhos)](+) (JohnPhos = 1,1'-biphenyl-2-yl)di-tert-butylphosphine) in compounds 1 and 2 were transferred to recombinant human serum albumin (rHSA)...
May 11, 2017: ACS Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/28522973/profiling-and-distribution-of-metabolites-of-procyanidin-b2-in-mice-by-uplc-dad-esi-it-tof-ms-n-technique
#13
Ying Xiao, Zhongzhi Hu, Zhiting Yin, Yiming Zhou, Taiyi Liu, Xiaoli Zhou, Dawei Chang
The metabolite profiles and distributions of procyanidin B2 were qualitatively described using UPLC-DAD-ESI-IT-TOF-MS(n) without help of reference standards, and a possible metabolic pathway was proposed in the present study. Summarily, 53 metabolites (24 new metabolites) were detected as metabolites of procyanidin B2, and 45 of them were tentatively identified. Twenty seven metabolites were assigned as similar metabolites of (-)-epicatechin by scission of the flavanol interflavanic bond C4-C8, including 16 aromatic metabolites, 5 conjugated metabolites, 3 ring-cleavage metabolites, and 2 phenylvalerolactone metabolites...
2017: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/28522339/proteomics-analysis-of-fusarium-proliferatum-under-various-initial-ph-during-fumonisin-production
#14
Taotao Li, Liang Gong, Yong Wang, Feng Chen, Vijai Kumar Gupta, Qijie Jian, Xuewu Duan, Yueming Jiang
Fusarium proliferatum as a fungal pathogen can produce fumonisin which causes a great threat to animal and human health. Proteomic approach was a useful tool for investigation into mycotoxin biosynthesis in fungal pathogens. In this study, we analyzed the fumonisin content and mycelium proteins of Fusarium proliferatum cultivated under the initial pH5 and 10. Fumonisin production after 10days was significantly induced in culture condition at pH10 than pH5. Ninety nine significantly differently accumulated protein spots under the two pH conditions were detected using two dimensional polyacrylamide gel electrophoresis and 89 of these proteins were successfully identified by MALDI-TOF/TOF and LC-ESI-MS/MS analysis...
May 15, 2017: Journal of Proteomics
https://www.readbyqxmd.com/read/28521570/two-novel-compounds-from-the-root-bark-of-morus-alba-l
#15
Ming Li, Xuewei Wu, Xiaoning Wang, Tao Shen, Dongmei Ren
Chemical investigation of the root bark of Morus alba led to the isolation of a new flavone, dioxycudraflavone A (1) and a new 2-arylbenzofuran, 5-hydroxyethyl moracin M (2), together with seven known compounds namely sanggenon V (3), morusin (4), morusignin L (5), licoflavone C (6), moracin C (7), alfafuran (8) and mulberrofuran G (9). The structure elucidation of these compounds was based on analyses of spectroscopic data including 1D, 2D NMR and HR-ESI-MS. All compounds were evaluated for the α-glucosidase inhibitory and cytotoxic activities...
May 19, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28521276/an-atmospheric-pressure-ionization-source-using-a-high-voltage-target-compared-to-electrospray-ionization-for-the-lc-ms-analysis-of-pharmaceutical-compounds
#16
Arnaud Lubin, Ronald De Vries, Deirdre Cabooter, Patrick Augustijns, Filip Cuyckens
The type and design of an ionization source can have a significant influence on the performances of a bioanalytical method. It is, therefore, of high interest to evaluate the performances of newly introduced sources to highlight their benefits and limitations in comparison to other well established sources. In this paper, liquid chromatography - mass spectrometry (LC/MS) performances of a new atmospheric pressure ionization (API) source, commercialized as UniSpray, is evaluated. The dynamic range of 24 pharmaceutical and biological compounds is compared between the new API source and electrospray ionization (ESI) for 3 different mobile phase conditions...
May 4, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28521190/simultaneous-determination-of-bisphenol-a-and-estrogens-in-hair-samples-by-liquid-chromatography-electrospray-tandem-mass-spectrometry
#17
Chaelin Lee, Chong Hyeak Kim, Sunghwan Kim, Sung-Hee Cho
Bisphenol A (BPA), an endocrine disrupter, is widely used to make chemicals for polycarbonate, plastics, beverage containers, epoxy resins, and cash register receipts. BPA is one of the known xenoestrogens, which have weak estrogenic activity and cause obesity, diabetes, breast cancer, and reproductive disorders. Even though the concentration level of metabolomes in hair is usually lower than that in urine and blood, there are several reasons why we chose to use hair samples. First, the sampling procedure of hairs is simple...
May 11, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28521188/bis-diphenylphosphino-amines-containing-ruthenium-cymene-complexes-as-potential-anti-mycobacterium-tuberculosis-agents
#18
Juliana P da Silva, Isabel C Silva, Fernando R Pavan, Davi F Back, Márcio P de Araujo
Several ruthenium complexes have been investigated regarding anti-Mycobacterium tuberculosis (anti-MTb) activity, with some diphosphine-containing ruthenium complexes comparable to first and second line drugs. However, to the best of our knowledge, there is no PNP-containing ruthenium complexes applied as metallodrugs. Thus, this study focused on the synthesis, characterization and anti-MTb activity of a new series of coordination compounds with general formula [RuCl(η(6)-p-cymene)(PN(R)P)]X (R=CH2Py (Py=pyridine)-[1a], CH2Ph (Ph=phenyl)-[1b], Ph-[1c] and p-tol (p-tol=p-tolyl)-[1d]; X=PF6(-) or BF4(-))...
April 9, 2017: Journal of Inorganic Biochemistry
https://www.readbyqxmd.com/read/28520404/enzymatic-reactor-with-trypsin-immobilized-on-graphene-oxide-modified-polymer-microspheres-to-achieve-automated-proteome-quantification
#19
Huiming Yuan, Shen Zhang, Baofeng Zhao, Yejing Weng, Xudong Zhu, Senwu Li, Lihua Zhang, YuKui Zhang
Protein digestion and isotope labeling are two critical steps in proteome quantification. However, the conventional in-solution protocol unavoidably suffers from disadvantages such as time-consuming, low labeling efficiency, and tedious off-line manual operation, which might affect the quantification accuracy, reproducibility and throughput. To address these problems, we developed a fully automated proteome quantification platform, in which an ultra-performance immobilized microreactor (upIMER) with graphene-oxide-modified polymer microspheres as the matrix was developed, to achieve not only the simultaneous protein digestion and 18O labeling, but also the on-line integration with nanoHPLC-ESI MS/MS...
May 18, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28516296/substrate-coated-illumination-droplet-spray-ionization-real-time-monitoring-of-photocatalytic-reactions
#20
Hong Zhang, Na Li, Dandan Zhao, Jie Jiang, Hong You
Real-time monitoring of photocatalytic reactions facilitates the elucidation of the mechanisms of the reactions. However, suitable tools for real-time monitoring are lacking. Herein, a novel method based on droplet spray ionization named substrate-coated illumination droplet spray ionization (SCI-DSI) for direct analysis of photocatalytic reaction solution is reported. SCI-DSI addresses many of the analytical limitations of electrospray ionization (ESI) for analysis of photocatalytic-reaction intermediates, and has potential for both in situ analysis and real-time monitoring of photocatalytic reactions...
May 17, 2017: Journal of the American Society for Mass Spectrometry
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