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991.
Azza Hanif Harisna Rizky Nurdiansyah Putri Hawa Syaifie Dwi Wahyu Nugroho Kurniawan Eko Saputro Chandra Dwi Prakoso Nurul Taufiqu Rochman Nurwenda Novan Maulana Alfian Noviyanto Etik Mardliyati 《Biochemistry and Biophysics Reports》2021
Docking analysis of propolis's natural compound was successfully performed against SARS-CoV-2 main protease (Mpro) and spike protein subunit 2 (S2). Initially, the propolis's protein was screened using chromatography analysis and successfully identified 22 compounds in the propolis. Four compounds were further investigated, i.e., neoblavaisoflavone, methylophiopogonone A, 3′-Methoxydaidzin, and genistin. The binding affinity of 3′-Methoxydaidzin was ?7.7 kcal/mol, which is similar to nelfinavir (control), while the others were ?7.6 kcal/mol. However, we found the key residue of Glu A:166 in the methylophiopogonone A and genistin, even though the predicted binding energy slightly higher than nelfinavir. In contrast, the predicted binding affinity of neoblavaisoflavone, methylophiopogonone A, 3′-Methoxydaidzin, and genistin against S2 were ?8.1, ?8.2, ?8.3, and ?8.3 kcal/mol, respectively, which is far below of the control (pravastatin, ?7.3 kcal/mol). Instead of conventional hydrogen bonding, the π bonding influenced the binding affinity against S2. The results reveal that this is the first report about methylophiopogonone A, 3′-Methoxydaidzin, and genistin as candidates for anti-viral agents. Those compounds can then be further explored and used as a parent backbone molecule to develop a new supplementation for preventing SARS-CoV-2 infections during COVID-19 outbreaks. 相似文献
992.
During the second blooming of a cultivated Amorphophallus gigas Teijsm and Binnend in the Botanical Gardens of the University of Tokyo, the surface temperature of the inflorescence was measured using an infrared camera. Contrary to studies of other species in the genus Amorphophallus, the surface of the inflorescence showed only very faint thermogenesis and had a lower temperature than that of the background. This cooling effect appeared to be due to a loss of heat through evaporation, which was caused by the secretion of a very large amount of odorous liquid. Chemical analysis revealed that the major components of this liquid were acetic acid, propionic acid, butyric acid and valeric acids. The composition of the odorous liquid was slightly different between the spathe surface and the sterile appendix. The major component(s) of the odorous material from the spathe was butyric acid, and from the sterile appendix was valeric acids. These components would play dual roles of adding the characteristic smell to the inflorescence and cooling the inflorescence. 相似文献
993.
Meriç Kumbaşlı Éric Bauce Sophie Rochefort Michèle Crépin 《Agricultural and Forest Entomology》2011,13(2):131-141
- 1 The effect of tannins and monoterpenes on the development, mortality and food utilization of spruce budworm Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae) was investigated under laboratory conditions using an artificial diet. Tannins were extracted from balsam fir foliage of thinned and unthinned stands to reproduce stand thinning related variations in tannins. A mixture of synthetic monoterpenes was utilized to simulate the concentration found in young and old balsam fir trees.
- 2 Longer development time and lower pupal weight were observed for insects fed on diets with a lower nitrogen concentration and a higher tannin concentration (unthinned treatment). Tannins induced higher insect mortality at a low nitrogen concentration compared with the diet with a higher nitrogen concentration.
- 3 Approximate digestibility was higher for larvae fed on diets with high concentrations of nitrogen at both low and high concentrations of tannins. Efficiency of conversion of digested food (ECD) decreased with an increase in tannin concentration. Tannins reduced both the relative consumption and growth rate (RCR and RGR).
- 4 Monoterpenes increased spruce budworm mortality and this mortality reached almost 50% under concentrations of monoterpene typical of the young trees compared with 20% under monoterpene concentrations found in old trees.
- 5 A higher digestibility was observed for larvae fed on diet with a higher concentration of monoterpenes, whereas efficiency of conversion of ingested food (ECI), ECD, RCR, and RGR decreased with an increase in monoterpenes in the diet.
- 6 The results obtained in the present study are consistent with the defensive role of secondary compounds such as tannins and monoterpenes in the spruce budworm–balsam fir system.
994.
The purpose of this study was to identify the antioxidant activity of 16 compounds isolated from Piper cubeba (CNCs) through the extent of their capacities to scavenge free radicals, hydroxyl radical (HO?), superoxide anion radical () and 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH?), in different systems. Electron paramagnetic resonance (EPR) and 5,5‐dimethyl‐1‐pyrroline‐N‐oxide, DMPO, as the spin trap, and chemiluminescence techniques were applied. Using the Fenton‐like reaction [Fe(II) + H2O2], CNCs were found to inhibit DMPO? OH radical formation ranging from 5 to 57% at 1.25 mmol L?1 concentration. The examined CNCs also showed a high DPPH antiradical activity (ranging from 15 to 99% at 5 mmol L?1 concentration). Furthermore, the results indicated that seven of the 16 tested compounds may catalyse the conversion of superoxide radicals generated in the potassium superoxide/18‐crown‐6 ether system, thus showing superoxide dismutase‐like activity. The data obtained suggest that radical scavenging properties of CNCs might have potential application in many plant medicines. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
995.
Brender JD Kelley KE Werler MM Langlois PH Suarez L Canfield MA;National Birth Defects Prevention Study 《Birth defects research. Part A, Clinical and molecular teratology》2011,91(4):258-264
BACKROUND
Experimental evidence indicates that certain drugs, that are secondary or tertiary amines or amides, form N‐nitroso compounds in the presence of nitrite in an acidic environment. Nitrosatable drugs have been associated with birth defects in a few epidemiologic studies. This study describes the prevalence and patterns of nitrosatable drug use among U.S. women during early pregnancy and examines maternal factors associated with such use.METHODS
Data were analyzed from the National Birth Defects Prevention Study and included 6807 mothers who gave birth to babies without major congenital malformations during 1997 to 2005. Information was collected by telephone interview about medication use, demographic factors, and maternal health. Drugs taken during the first trimester were classified according to nitrosatability, amine and amide functional groups, and primary indication of use.RESULTS
Approximately 24% of the women took one or more nitrosatable drugs during the first trimester, including 12.4%, 12.2%, and 7.6% who respectively took secondary amines, tertiary amines, or amides. Five of the ten most commonly taken drugs were available over the counter. Women who were non‐Hispanic white (29.5%), with 1 year or more college education (27.3%) or 40 years or older (28.8%) had the highest prevalence of use. Supplemental vitamin C, an inhibitor of nitrosation, was not taken by 41.6% and 19.3% of nitrosatable drug users during the first and second months of pregnancy, respectively.CONCLUSIONS
In this U.S. population, ingestion of drugs classified as nitrosatable was common during the first trimester of pregnancy, especially among non‐Hispanic white, more educated, and older mothers. Birth Defects Research (Part A) 2011. © 2011 Wiley‐Liss, Inc. 相似文献996.
Gentiana rhodantha Franch. ex Hemsl. (Gentianaceae), an annual herb widely distributed in the southwest of China, has been medicinally used for the treatment of inflammation, cholecystitis, and tuberculosis by the local people of its growing areas. Chemical investigation on the whole plants led to the identification of eight new phenolic compounds, rhodanthenones A–D ( 1 – 4 , resp.), apigenin 7‐O‐glucopyranosyl‐(1→3)‐glucopyranosyl‐(1→3)‐glucopyranoside ( 5 ), 1,2‐dihydroxy‐4‐methoxybenzene 1‐O‐α‐L ‐rhamnopyranosyl‐(1→6)‐β‐D ‐glucopyranoside ( 6 ), 1,2‐dihydroxy‐4,6‐dimethoxybenzene 1‐O‐α‐L ‐rhamnopyranosyl‐(1→6)‐β‐D ‐glucopyranoside ( 7 ), and methyl 2‐O‐β‐D ‐glucopyranosyl‐2,4,6‐trihydroxybenzoate ( 8 ), together with eleven known compounds, 9 – 19 . Their structures were determined on the basis of detailed spectroscopic analyses and chemical methods. Acetylcholinesterase (AChE) inhibition and cytotoxicity tests against five human cancer cell lines showed that only rhodanthenone D ( 4 ) and mangiferin ( 12 ) exhibited 18.4 and 13.4% of AChE inhibitory effects at a concentration of 10−4 M , respectively, while compounds 1 – 5 and the known xanthones lancerin ( 11 ), mangiferin ( 12 ), and neomangiferin ( 13 ) displayed no cytotoxicity at a concentration of 40 μM . 相似文献
997.
Joh LD Rezaei F Barabote RD Parales JV Parales RE Berry AM Vandergheynst JS 《Biotechnology progress》2011,27(1):23-31
Previous studies on biological pretreatment of switchgrass by solid-state fermentation with Acidothermus cellulolyticus 11B have shown that inhibitory compounds prevent growth on untreated switchgrass. A. cellulolyticus was grown in liquid medium containing cellobiose with phenolic monomers added to determine if the phenolic compounds are one possible source of inhibition. Cinnamic acid derivatives (trans-p-coumaric, trans-ferulic, and hydrocinnamic acids), hydroxybenzoic acids (p-hydroxybenzoic, syringic, and vanillic acids), benzaldehydes (vanillin and p-hydroxybenzaldehyde), and condensed tannin monomers (catechin and epicatechin) were tested at levels up to 20 mM. All compounds exhibited a dose-response relationship and strongly inhibited growth at 20 mM. trans-p-Coumaric acid was found to be the strongest inhibitor of A. cellulolyticus growth, with a specific growth rate of 0.004 h(-1) at 1 mM (0.18 h(-1) without phenolic monomer). GC-MS and HPLC methods were used to confirm the presence of these phenolic compounds in switchgrass and measure the amounts extracted using different conditions. The amounts of phenolic compounds measured were found to be higher than the threshold for growth inhibition. Leaching with water at 55°C was inefficient at removing bound phenolics, whereas NaOH treatment improved efficiency. Phenolic compounds spiked into alkaline pretreated switchgrass were also found to inhibit growth of A. cellulolyticus in solid-state fermentation. However, addition of insoluble polyvinylpolypyrrolidone (PVPP) to switchgrass improved growth of A. cellulolyticus in liquid cultures, providing a possible approach for alleviating microbial inhibition due to phenolic compounds in lignocellulose. 相似文献
998.
K.V. Niessen T. Seeger J.E.H. Tattersall C.M. Timperley M. Bird C. Green H. Thiermann F. Worek 《Chemico-biological interactions》2013
The toxicity of organophosphorus nerve agents or pesticides arises from accumulation of acetylcholine and overstimulation of both muscarinic and nicotinic acetylcholine receptors (mAChRs and nAChRs) due to inhibition of acetylcholinesterase (AChE). Standard treatment by administration of atropine and oximes, e.g., obidoxime or pralidoxime, focuses on antagonism of mAChRs and reactivation of AChE, whereas nicotinic malfunction is not directly treated. An alternative approach would be to use nAChR active substances to counteract the effects of accumulated acetylcholine. Promising in vitro and in vivo results were obtained with the bispyridinium compounds SAD-128 (1,1′-oxydimethylene bis(4-tert-butylpyridinium) dichloride) and MB327 (1,1′-(propane-1,3-diyl)bis(4-tert-butylpyridinium) di(iodide)), which were partly attributed to their interaction with nAChRs. In this study, a homologous series of unsubstituted and 4-tert-butyl-substituted bispyridinium compounds with different alkane linker lengths was investigated in competition binding experiments using [3H]epibatidine as a reporter ligand. Additionally, the effect of the well-characterised MB327 on the [3H]epibatidine equilibrium dissociation (KD) constant in different buffers was determined. This study demonstrated that divalent cations increased the affinity of [3H]epibatidine. Since quaternary ammonium molecules are known to inhibit AChE, the obtained affinity constants of the tested bispyridinium compounds were compared with the inhibition of human AChE. In competition experiments, bispyridinium derivatives of longer linker length displaced [3H]epibatidine and inhibited AChE strongly. Bispyridinium compounds with short linkers, at most, have an allosteric interaction with the [3H]epibatidine binding sites and barely inhibited AChE. In dependence on alkane linker length, the bispyridinium compounds seemed to interact at different binding sites. However, the exact binding sites of the bispyridinium compounds responsible for the positive pharmacological effects have still not been identified, making predictive drug design difficult. 相似文献
999.
1000.
Patricia J. S. Colberg 《Geomicrobiology journal》2013,30(3-4):147-165
Despite recent progress made in describing microbial transformations that occur under anaerobic conditions, our understanding of the role sulfate‐reducing bacteria may play in the remediation of environmental contaminants is still very limited. The objective of this mini‐review is to summarize what is currently known of the metabolism of chlorinated aromatic compounds in the presence of sulfate. Sulfidogenic processes are discussed with respect to the thermodynamics of haloaromatic oxidation and to their potential use in the in situ bioremediation of hazardous organic wastes. A comprehensive listing is made of anaerobic transformations that involve both halogenated and nonhalogenated monoaromatic substrates by denitrifiers, dissimilatory iron‐reducing bacteria, and methanogenic consortia. In contrast to other anaerobic processes, studies involving sulfate‐mediated metabolism of hazardous organic compounds have been neglected; however, the recent success in defining methanogenic transformations, in particular, has enhanced expectations of defining an analogous role for sulfate‐reducing microbial communities in low redox environments that have become contaminated with hazardous substances. 相似文献