V A Pure compounds

Author(s):  
M. Adachi
Keyword(s):  
Planta Medica ◽  
2015 ◽  
Vol 81 (16) ◽  
Author(s):  
K Teichmann ◽  
D Wendner ◽  
D Bachinger ◽  
S Hessenberger ◽  
G Schatzmayr

2019 ◽  
Author(s):  
J. Rocha-Pimienta ◽  
J. Espino ◽  
S. Martillanes ◽  
A.B. Rodríguez ◽  
J. Delgado-Adámez

2012 ◽  
pp. 84-89
Author(s):  
Quoc Hung Vo ◽  
Nguyen Phuong Nhi Doan ◽  
Dinh Quynh Phu Nguyen ◽  
Thi Dieu Tram Ho ◽  
Thi Hoai Nguyen

Objectives: Nowadays, bioactive substances isolated from marine organisms which are abundant and varied in Vietnamese sea attracted more and more the attention of scientists in the world and Vietnam as well. We have studied on soft coral Sinularia cruciata – Alcyoniidae, which has never been studied in Vietnam before, to find substances which are useful in medical field, especially in anti-cancer therapy. Materials and method: Specimens of soft coral Sinularia cruciata were collected from Con Co, Quang Tri province in May 2011. Pure compounds were isolated by using Thin Layer Chromatography; Column Chromatography normal phase and inverse phase; Shephadex LH 20. Structures of them were determined by spectral data of Nuclear Magnetic Resonance (NMR), Electrospray Ionization Mass Spectrometry (ESI-MS). Results & Conclusion: Structures of 4 compounds were identified: (1) 5.8-epidioxycholest-6-en-3-ol (2) Cholesterol (3) 1-O-hexadecyl-glycerol (Chimyl alcohol) (4) Glycerol 1-O-octadecyl ether (Batyl alcohol). The substance (1) was demonstrated to have strong anti-cancer effects in previous study. Key words Sinularia cruciata, Alcyoniidae, 5,8-epidioxycholest-6-en-3-ol, soft coral, cancer.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Josephine F. Reijneveld ◽  
Mira Holzheimer ◽  
David C. Young ◽  
Kattya Lopez ◽  
Sara Suliman ◽  
...  

AbstractThe cell wall of Mycobacterium tuberculosis is composed of diverse glycolipids which potentially interact with the human immune system. To overcome difficulties in obtaining pure compounds from bacterial extracts, we recently synthesized three forms of mycobacterial diacyltrehalose (DAT) that differ in their fatty acid composition, DAT1, DAT2, and DAT3. To study the potential recognition of DATs by human T cells, we treated the lipid-binding antigen presenting molecule CD1b with synthetic DATs and looked for T cells that bound the complex. DAT1- and DAT2-treated CD1b tetramers were recognized by T cells, but DAT3-treated CD1b tetramers were not. A T cell line derived using CD1b-DAT2 tetramers showed that there is no cross-reactivity between DATs in an IFN-γ release assay, suggesting that the chemical structure of the fatty acid at the 3-position determines recognition by T cells. In contrast with the lack of recognition of DAT3 by human T cells, DAT3, but not DAT1 or DAT2, activates Mincle. Thus, we show that the mycobacterial lipid DAT can be both an antigen for T cells and an agonist for the innate Mincle receptor, and that small chemical differences determine recognition by different parts of the immune system.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1406
Author(s):  
Rita Cava-Roda ◽  
Amaury Taboada-Rodríguez ◽  
Antonio López-Gómez ◽  
Ginés Benito Martínez-Hernández ◽  
Fulgencio Marín-Iniesta

Plant bioactive compounds have antimicrobial and antioxidant activities that allow them to be used as a substitute for synthetic chemical additives in both food and food packaging. To improve its sensory and bactericidal effects, its use in the form of effective combinations has emerged as an interesting possibility in the food industry. In this study, the antimicrobial activities of essential oils (EOs) of cinnamon bark, cinnamon leaves, and clove and the pure compounds vanillin, eugenol, and cinnamaldehyde were investigated individually and in combination against Listeria monocytogenes and Escherichia coli O157:H7. The possible interactions of combinations of pure compounds and EOs were performed by the two-dimensional checkerboard assay and isobologram methods. Vanillin exhibited the lowest antimicrobial activity (MIC of 3002 ppm against L. monocytogenes and 2795 ppm against E. coli O157:H7), while clove and cinnamon bark EOs exhibited the highest antimicrobial activity (402–404 against L. monocytogenes and 778–721 against E. coli O157:H7). For L. monocytogenes, pure compound eugenol, the main component of cinnamon leaves and clove, showed lower antimicrobial activity than EOs, which was attributed to the influence of the minor components of the EOs. The same was observed with cinnamaldehyde, the main component of cinnamon bark EO. The combinations of vanillin/clove EO and vanillin/cinnamon bark EO showed the most synergistic antimicrobial effect. The combination of the EOs of cinnamon bark/clove and cinnamon bark/cinnamon leaves showed additive effect against L. monocytogenes but indifferent effect against E. coli O157:H7. For L. monocytogenes, the best inhibitory effects were achieved by cinnamon bark EO (85 ppm)/vanillin (910 ppm) and clove EO (121 ppm)/vanillin (691 ppm) combinations. For E. coli, the inhibitory effects of clove EO (104 ppm)/vanillin (1006 ppm) and cinnamon leaves EO (118 ppm)/vanillin (979 ppm) combinations were noteworthy. Some of the tested combinations increased the antimicrobial effect and would allow the effective doses to be reduced, thereby offering possible new applications for food and active food packaging.


Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 781
Author(s):  
Agnieszka Raczyńska ◽  
Joanna Jadczyk ◽  
Małgorzata Brzezińska-Rodak

The enantioselective synthesis of organic compounds is one of the great challenges in organic synthetic chemistry due to its importance for the acquisition of biologically active derivatives, e.g., pharmaceuticals, agrochemicals, and others. This is why biological systems are increasingly applied as tools for chiral compounds synthesis or modification. The use of whole cells of “wild-type” microorganisms is one possible approach, especially as some methods allow improving the conversion degrees and controlling the stereoselectivity of the reaction without the need to introduce changes at the genetic level. Simple manipulation of the culture conditions, the form of a biocatalyst, or the appropriate composition of the biotransformation medium makes it possible to obtain optically pure products in a cheap, safe, and environmentally friendly manner. This review contains selected examples of the influence of physicochemical factors on the stereochemistry of the biocatalytic preparation of enantiomerically pure compounds, which is undertaken through kinetically controlled separation of their racemic mixtures or reduction of prochiral ketones and has an effect on the final enantiomeric purity and enantioselectivity of the reaction.


Fermentation ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 19
Author(s):  
Anastasia Zerva ◽  
Nikolaos Tsafantakis ◽  
Evangelos Topakas

White-rot basidiomycetes are the only microorganisms with the ability to produce both hydrolytic (cellulases and hemicellulases) and oxidative (ligninolytic) enzymes for degrading cellulose/hemicellulose and lignin. In addition, they produce biologically active natural products with important application in cosmetic formulations, either as pure compounds or as standardized extracts. In the present work, three wild strains of Basidiomycetes fungi (Pleurotus citrinopileatus, Abortiporus biennis and Ganoderma resinaceum) from Greek habitats were grown in agro-industrial residues (oil mill wastewater, and corn cob) and evaluated for their anti-tyrosinase and antioxidant activity and for the production of biotechnologically relevant enzymes. P. citrinopileatus showed the most interesting tyrosinase inhibitory activity, while A. biennis showed the highest DPPH(2,2-diphenyl-1-picryl-hydrazyl) scavenging potential. Corn cobs were the most appropriate carbon source for maximizing the inhibitory effect of fungal biomasses on both activities, while the use of oil mill wastewater selectively increased the anti-tyrosinase potential of P. citrinopileatus culture filtrate. All strains were found to be preferential lignin degraders, similarly to most white-rot fungi. Bioinformatic analyses were performed on the proteome of the strains P. citrinopileatus and A. biennis, focusing on CAZymes with biotechnological relevance, and the results were compared with the enzyme activities of culture supernatants. Overall, all three strains showed strong production of oxidative enzymes for biomass conversion applications.


Author(s):  
Akihiro Yoshimura ◽  
Shunta Tochigi ◽  
Yasunari Matsuno

AbstractIn this research, a recycling process for palladium using “dry aqua regia,” which consists of iron(III) chloride–potassium chloride, was proposed. Palladium was dissolved in “dry aqua regia,” and the dissolved palladium was recovered by leaching with potassium chloride solution with added ammonium chloride and nitric acid. Palladium was almost completely dissolved in 3 h at 600 K, and the recovery ratio of dissolved palladium was up to 80%. In addition, the dissolution of palladium in coexistence with platinum and the dissolution of platinum-palladium alloy by “dry aqua regia” were also tested. The dissolved palladium and platinum were separated and recovered by solid–liquid separation technique using the difference in solubility of their compounds in potassium chloride and sodium chloride solutions. As a result, pure compounds of each element were recovered. This result suggested the possibility of using “dry aqua regia” for the separation of platinum-group metals. Graphical Abstract


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Bernadette R. Cladek ◽  
S. Michelle Everett ◽  
Marshall T. McDonnell ◽  
Matthew G. Tucker ◽  
David J. Keffer ◽  
...  

AbstractA vast source of methane is found in gas hydrate deposits, which form naturally dispersed throughout ocean sediments and arctic permafrost. Methane may be obtained from hydrates by exchange with hydrocarbon byproduct carbon dioxide. It is imperative for the development of safe methane extraction and carbon dioxide sequestration to understand how methane and carbon dioxide co-occupy the same hydrate structure. Pair distribution functions (PDFs) provide atomic-scale structural insight into intermolecular interactions in methane and carbon dioxide hydrates. We present experimental neutron PDFs of methane, carbon dioxide and mixed methane-carbon dioxide hydrates at 10 K analyzed with complementing classical molecular dynamics simulations and Reverse Monte Carlo fitting. Mixed hydrate, which forms during the exchange process, is more locally disordered than methane or carbon dioxide hydrates. The behavior of mixed gas species cannot be interpolated from properties of pure compounds, and PDF measurements provide important understanding of how the guest composition impacts overall order in the hydrate structure.


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