Kinds Of Phenols Research Articles

A novel laccase-like Cu-MOF for colorimetric differentiation and detection of phenolic compounds

The development of convenient, fast, and cost-effective methods for differentiating and detecting common organic pollutant phenols has become increasingly important for environmental and food safety. In this study, a copper metal-organic framework (Cu-MOF) with flower-like morphology was synthesized using 2-methylimidazole (2-MI) as ligands. The Cu-MOF was designed to mimic the natural laccase active site and proved demonstrated excellent mimicry of enzyme-like activity. Leveraging the superior properties of the constructed Cu-MOF, a colorimetric method was developed for analyzing phenolic compounds. This method exhibited a wide linear range from 0.1 to 100 μM with a low limit of detection (LOD) of 0.068 μM. Besides, by employing principal component analysis (PCA), nine kinds of phenols was successfully distinguished and identified. Moreover, the combination of smartphones with RGB profiling enabled real-time, quantitative, and high-throughput detection of phenols. Therefore, this work presents a paradigm and offers guidance for the differentiation and detection of phenolic pollutants in the environment.

The Relationship between Microbial Community Succession and Flavor Formation during the Natural Fermentation of Hongqu sufu.

To study the diversity of microbial flora in Hongqu sufu and analyze the characteristics of special flavor compounds, this study took self-made Hongqu sufu as the research object. Dynamic changes in sufu during fermentation were studied. High-throughput sequencing (HTS) was used to analyze changes in the diversity of fungal and bacterial communities during fermentation. The results showed that at the phylum level, the dominant fungal phyla were identified, Mucormyces and Ascomycetes. The dominant bacterial phyla were Proteobacteria and Firmicutes. At the genus level, the dominant fungal genera were identified as Actinomucor, Monascus, and Aspergillus. The dominant bacterial genera were Pseudomonas, Aneurimibacillus, Sphingobacterium, and Bacillus. Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with technology that can dynamically change flavor compounds was explored to investigate the correlation between microbiota and flavor compounds. In different stages of fermentation, 75 main volatile organic compounds were identified, including seven alcohols, four acids, 16 alkanes, 14 olefins, seven kinds of aldehydes, two kinds of ketones, 10 kinds of esters, one kind of phenol, one kind of sulfur-containing compound, one benzene, and 12 other compounds. The correlation analysis between flora and flavor compounds showed that the fungi genera Alternaria and Pichia were significantly correlated with most flavor compounds. Bacteria genera including Weissella, Hafnia-Obesumbacterium, and Leuconostoc had a strong positive correlation with ethyl oleate.

Synthesis and Characterization of Pyrimidine‐Based Novel Phthalonitrile Resins with Excellent Processing Performance and High Glass Transition Temperature

AbstractThree phthalonitrile monomers containing pyrimidine ring and benzene ring side group were successfully synthesized with 4, 6‐dichloro‐2‐phenylpyrimidine, three kinds of phenols (resorcinol, bisphenol A and bisphenol AF) and 4‐nitrophthalonitrile via nucleophilic substitution reaction. All the phthalonitrile monomers exhibited excellent processing performance due to low melting points (Tm) (below 100 °C) and wide processing windows (difference between melting temperature and curing temperature) above 140 °C. By introducing pyrimidine ring and benzene ring side group, the lower melting point of monomers did not affect the thermal stability and thermal mechanical properties of the phthalonitrile resins based on different bisphenols. In particular, 5 % thermal decomposition temperature (T5%) and glass transition temperature (Tg) of phthalonitrile resin based on resorcinol surpassed 455 and 400 °C while storage modulus (E′) was 3209 MPa. Therefore, phthalonitrile resin containing pyrimidine ring and benzene ring side group have potential applications in the field of high temperature resistant polymers and composites.

Identification of binding sites for Tartary buckwheat protein-phenols covalent complex and alterations in protein structure and antioxidant properties

To investigate the effects of structure, multiple binding sites and antioxidant property of Tartary buckwheat protein-phenols covalent complex, protein was combined with different concentrations of phenolic extract. Four kinds of phenols were identified by UPLC-Q/TOF-MS, which were rutin, quercetin, kaempferol and myricetin. UV–vis absorption spectroscopy and X-ray diffraction showed that the phenols can successfully bind to BPI. Fourier-transform infrared, circular dichroism and fluorescence emission spectroscopy showed that the binding of phenol can change the secondary/tertiary structure of protein. The particle distribution indicated that the binding of phenols could reduce the particle size (from 304.70 to 205.55 nm), but cross-linking occurred (435.35 nm) when the bound phenol content was too high. Proteomics showed that only rutin, quercetin and myricetin can covalently bind to BPI. Meanwhile, 4 peptides covalently bound to phenols were identified. The DPPH· scavenging capacity of complexes were from 8.38 to 33.76 %, and the ABTS·+ binding activity of complexes were from 19.35 to 63.99 %. The antioxidant activity of the complex was significantly higher than that of the pure protein. These results indicated that protein-phenol covalent complexes had great potential as functional components in the food field.

Dual-Channel Ratiometric Colorimetric Sensor Array for Quantification and Discrimination of o-, m-, and p-Phenols

The determination of trace o-, m-, and p-phenols in food samples was of great significance, but it is still very challenging due to the low concertation and complex matrix. In comparison to traditional sensors based on the “lock-and-key” strategy, the sensor arrays that mimicked the human olfactory system exhibited excellent universality and efficiency in assays of structural analogs. Herein, we described a costless and robust colorimetric sensor array for quantification and discrimination of o-, m-, and p-phenols. The obtained Cu2(OH)3Cl and Ni-doped Cu2(OH)3Cl with peroxidase-like (POD) activity were served as nanozymes to accelerate the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) with H2O2. UV–vis absorbance spectroscopy displayed remarkable enhancements both at 652 nm and 450 nm, individually attributable to the formation of single and dual electron-oxidized TMB (TMBox) substances. Then varied phenols regulated the absorbance via specific electron transfer processes. With the two peaks as dual signals, a ratiometric colorimetric sensor array based on nanozymes (i.e., Cu2(OH)3Cl and Ni-doped Cu2(OH)3Cl) was designed to monitor different phenols. The ratio (I652/I450) was recorded to quantify phenols sensitively, where internal reference ruled out interferences from the environment and equipment. Moreover, this array was also explored for simultaneous discrimination of o-, m-, and p-phenols. By integrating with colorimetric fingerprints and principal component analysis (PCA), each kind of phenol can be distinctly discriminated even at a very low concentration. This work demonstrated the reliability of a ratiometric sensor array for the recognition of multiple phenols.

Analysis of Volatile Components in Gui Qi Mango Fruit Wine

The volatile components in Gui Qi Mango fruit wine analyzed by headspace solid-phase microextraction-gas chromatography-mass spectrometry. Results showed that 32 kinds of volatile components were detected in Gui Qi Mango fruit wine, including 7 kinds of alcohols (65.69%), 17 kinds of esters (28.92%), 4 kinds of alkanes (2.16%), 3 kinds of aldehydes (0.36%), 2 kinds of olefins (0.32%), 1 kinds of ketones (0.41%), 1 kinds of phenols (0.2%). In the all of the volatile components, the relative content of alcohols and esters were 94.61%. The fermentation process had an effect on the Gui Qi Mango fruit wine, and alcohols and esters played a positive role in the aroma of Gui Qi Mango fruit wine.

Tribological and antioxidation properties study of two N-containing borate ester derivatives as additive in rapeseed oil.

Two kinds of phenol- and N- containing borate ester, BTEB and BMEB have good hydrolysis stability due to the B-N coordination bond. The PB value improved by 60.7% and 67.6% respectively at 0.5wt% BTEB, BMEB in rapeseed oil. Their antiwear effect increases with the increase of adding content, and BMEB is better than BTEB. The friction-reducing effect of BTEB is better than BMEB. All additives formed a protective film which containing BOx, FeOx and other organic nitrogen compounds. The better capacities of BMEB may due to the complex boundary lubricating film which contain ferrous sulfate, ferrous sulfide. All additives possessed good antioxidation effect, and it increased the oxidation activation energy than rapeseed oil by 51.15% and 78.82% respectively at 0.25wt%.

Electrochemical reverse engineering to probe for drug-phenol redox interactions

Phenolics are among the most abundant organics in nature but their biological activities remain poorly understood. Traditional approaches to characterize materials starts with structure determination yet this approach has been less successful for phenolics because of their structural complexity and heterogeneity. Here an electrochemical reverse engineering approach that focuses on materials properties (vs structure) was used to infer function. We studied three phenolics that are abundant in food: the small molecule chlorogenic acid, the macromolecule proanthocyanidins, and the insoluble tannin from persimmon. We observed that all three phenolics are redox active and can repeatedly donate and accept electrons. Further, we provide evidence that all three kinds of phenolics can undergo redox-cycling with the analgesic acetaminophen. These results suggest that the reversible redox properties of phenolics may confer important biological activities even under conditions that would suggest they are unavailable biologically because their size would restrict absorption into the bloodstream or even dissolution.

Relationship in between Chemical Oxidation and Browning of Flavanols

Catechin, epicatechin and chlorogenic acid are widely distributed in the plant kingdom. At present, influencing factors of phenol chemical oxidation is little research. In order to study non-enzymatic browning factors, this research utilized catechin, epicatechin and chlorogenic acid to establish simulation systems. The browning degree and products of flavanols were investigated by transmittance and high-performance liquid chromatography (HPLC). The main results and conclusions were follows. The brown generation is increased after phenols of chemical oxidation at 50°C and at pH 3.7 phosphate buffered saline, the sequence of influencing factor of browning is pH > kind of phenol > temperature. Oxidation of compounds of catechin and epicatechin results in formation of their Methylene quinone or o -Quinones. In addition, oxidation products of catechin, epicatechin and chlorogenic acid were mixture of different molecular sizes. The research has showed that brown generation correlated well with chemical oxidation of phenols and chemical oxidation reaction generated larger molecular weight polymers.

A New Strategy for the Enzymatic Degradation of Sudan Dyes in Non-alkaline Conditions

Sudan dyes are widely used as coloring agents in various solvents, waxes, and polishes. However, the dyes are environmental contaminants and Sudan I is a weak carcinogen, and its removal from wastewater remains challenging. Here, we developed a new strategy for Sudan dye degradation for use in the non-alkaline conditions typically found in wastewater. By combing glucose oxidase (GOD) and horseradish peroxidase (HRP), we avoided the hydrogen peroxide-induced HRP damage and inactivation. Moreover, the GOD-HRP-coupled degradation of Sudan dyes were enhanced by the addition of different kinds of phenols. Systematic investigations were carried out to determine the optimal process parameters (i.e., phenol concentration, pH value, temperature, and enzyme dose) for degrading Sudan I with GOD and HRP. Also, this strategy could be applied to degradation of Sudan II and Sudan III. We were also able to co-express GOD and HRP in a prokaryotic-like polycistronic expression system in Pichia pastoris, based on the internal ribosome entry sites (IRES). Therefore, this fermented liquid containing GOD and HRP might be used in the future to degrade pollutants in weakly acidic conditions.

Preparation and Characterization of Polyhydroxybutyrate-Bamboo Lignophenol Biocomposite Films

Four kinds of lignophenols (Lps) were derived from native bamboo (Sinocalamus affinis) lignin through phase separation system by using four kinds of phenols (p-cresol, catechol, resorcinol and pyrogallol) as derivatives and 72% concentrated sulfuric acid as catalyst. The resulting lignophenols were characterized by 1H-NMR, FT-IR, and GPC analysis. Then they were blended with polyhydroxybutyrate (PHB) to cast thin biocomposite films. The mechanical properties, water-absorbing qualities, and thermal properties of films were tested and discussed. The results indicated that phase separation treatment can effectively improve phenolic hydroxyl contents of lignins. The lignin macromolecule was significantly reduced to small size and well-soluble polymers. The best amounts of added Lps in composite films depended upon the kind of phenols. In present study, the mechanical properties, water-absorbing qualities, and thermal properties of biocomposite films showed good results at less than 10% Lps’ addition. This provides a possibility that a new kind of biodegradable films can be made up of engineering plastics and lignin.

Estimate of consumption of phenolic compounds by Brazilian population

OBJECTIVE: Estimate the intake of phenolic compounds by the Brazilian population. METHODS: To estimate the average per capita food consumption, micro data from the National Dietary Survey and from the Household Budget Survey from 2008 to 2009 was analyzed. The phenolic content in food was estimated from the base of Phenol-Explorer. It was chosen according to compatibility and variety of food items and usual method of preparation. RESULTS: The Brazilian population consumed, on average, 460.15 mg/day of total phenolic compounds, derived mainly from beverages (48.9%), especially coffee and legumes (19.5%). Since this analysis of classes of phenolics it was possible to observe an intake of 314 mg/day of phenolic acids, 138.92 mg/day of flavonoids and 7.16 mg/ day of other kinds of phenolics. Regarding the variables studied this present study shows that those men who live in the countryside and in the northeastern region of the country had a higher consumption of phenolic compounds. Besides, consumption was higher by adults and the elderly, the medium income classes, the population with incomplete and complete primary education and those with adequate nutrition and also overweight status. CONCLUSION: The intake of phenolic compounds can be considered low, especially where consumption of fruit and vegetables is insufficient. We can conclude that coffee and black beans were the best contributors to phenolic intake.

Bioassay-based isolation and identification of phenolics from sweet cherry that promote active glucose consumption by HepG2 cells.

A variety of phenolics had been found to be functional in promoting cellular glucose consumption that is important for blood glucose regulation. Sweet cherry (Prunus avium) is rich in such kinds of phenolics, including hydrocinnamic acids, anthocyanins, flavonols, and flavan-3-ols. Furthermore, a sweet cherry phenolics-rich extract (PRE) was found to be effective in promoting HepG2 glucose consumption. Seventeen components were preliminarily identified by HPLC-ESI-MS, including 9 hydrocinnamic acids, 4 anthocyanins, 3 flavonols, and 1 flavan-3-ol. To investigate the cellular glucose consumption-promotion activity of different phneolics subclasses, the phenolics were further fractionated into an anthocyanin-rich fraction (ARF), hydrocinnamic acid-rich fraction (HRF), and flavonol-rich fraction (FRF) through liquid-liquid extraction and mix-mode cation-exchange solid-phase extraction. The 3 fractions promoted HepG2 glucose consumption to different levels, with the promotion effects of HRF and FRF stronger than that of the ARF. The results provide guidance on the use of sweet cherry as a functional fruit.

Comparative analysis of phenolic profile of Monodora myristica and Monodora tenuifolia

This study sought to identify phenolics present in the seeds of Monodora myristica and Monodora tenuifolia by Gas chromatography (GC) coupled to Flame ionization detector (FID). GC-FID analysis identified fifty-three different types of phenolics in both M. myristica and M. tenuifolia seeds. Predominant phenolics are Myristicin (RT: 13.78), Caffeic acid (RT: 14.16), Safrole (RT: 11.37), Methyl Eugenol (RT: 12.32), Catechin (RT: 3.63), Elemicin (RT: 13.69), Quercetin (RT: 25.05), Kaempherol (RT: 21.52), Methyl Isoeugenol (RT: 12.69) and Eugenol (RT: 11.70). It was observed that M. myristica is rich in Myristicin (42.60%), Caffeic acid (23.39%), Elemicin (3.82%) and Eugenol (1.02%), while M. tenuifolia is rich in Safrole (11.86%), Methyl Eugenol (6.28%), Catechin (5.27%), Quercetin (2.97%), Kaempherol (2.27%) and Methyl Isoeugenol (1.45%). However, the two species of Monodora contained virtually the same kinds of phenolics but in varying quantities with M. myristica having a higher total phenolic content (1478.32 mg/100 g) than M. tenuifolia (1171.52 mg/100 g). Both species are promising sources of phenolics. Key words: Monodora myristica, Monodora tenuifolia, phenolics.

An Ullmann CO Coupling Reaction Catalyzed by Magnetic Copper Ferrite Nanoparticles

AbstractHerein, an efficient method for the Ullmann CO coupling reaction between various kinds of phenols and aryl halides, including amino, ketone, cyano, methyl, methoxy, fluoro, chloro and bromo derivatives, is described. The catalyst used, copper ferrite (CuFe2O4) nanoparticles, are easily made, air‐stable, and of low cost. The catalyst can be recycled easily just by using an external magnet. Even in the presence of sensitive substituents, the reaction proceeds successfully to provide the desired products in high yields without protection of other functional groups.

ChemInform Abstract: Calixarene‐Based Supramolecular Polymerization in Solution

AbstractReview: 67 refs.

Silica supported boric tri-sulfuric anhydride as a novel and efficient catalyst for solvent-free synthesis of coumarins via Pechmann condensation

It is found that silica supported boric trisulfuric anhydride (BTSA.SiO 2) is a novel, suitable and versatile catalyst for efficient and clean synthesis of coumarins via Pechmann cyclocondensation under mild and solvent-free conditions. Different kinds of phenols and �-ketoesters were subjected to the cyclization reaction. Particularly, this catalyst makes the condensation of less activated phenols feasible. Besides the described benefits, the reported catalyst was applied successfully for the synthesis of novel coumarins from 3-acetyldihydrofuran-2(3 H)-one as well as estradiol (sex hormone).

Enhanced chemiluminescence of the luminol-K3Fe(CN)6 system by ZnSe quantum dots and its application

In this study, water-soluble ZnSe quantum-dots (QDs) capped with Glutathione(GSH) was synthesized. It was found that ZnSe QDs could enhance the chemiluminescence (CL) emission from the luminol-K3Fe(CN)6 system in alkaline medium, and the enhancement mechanism of ZnSe QDs on luminol CL was discussed. What's more, we found that the CL from luminol-K3Fe(CN)6–ZnSe QDs system is strongly inhibited by the presence of phenols. Based on this inhibition, a novel CL method with a lower detection limit and wider linear range was developed for the determination of three kinds of phenols.

Application of Polymer Quantum Dot-Enzyme Hybrids in the Biosensor Development and Test Paper Fabrication

Both glutathione capped CdTe quantum dots (QDs) and enzymes were encapsulated with poly(diallyldimethylammonium chloride) (PDDA) via electrostatic attraction to form hybrid films. The obtained PDDA QD-enzyme hybrids feature both high fluorescence and biorecognition. In the obtained hybrid materials, the fluorescence emission of the QDs was stable for at least 3 months, and the structure and activity of the enzyme was also well maintained as the Michaelis constant of tyrosinase was determined to be 0.90 mmol/L, which is just 2 times higher than that of free enzyme. This hybrid material was then utilized as a platform for the development of biosensors based on the quenching effects of the enzymatic products on the emission of the QDs with a kind of phenol (catechol) and glucose as example analytes. The detection limits of catechol and glucose were 1.0 × 10(-5) and 5.0 × 10(-6) mol/L, respectively. Moreover, this hybrid material was applied to the fabrication of test paper for these two analytes. The test paper was very stable with respect to the fluorescence of the QDs and the activity of the enzyme maintained for at least 1 month.

A Supramolecular Polymer of Nitroxide Radicals via Hydrogen Bonding

AbstractSummary: 2,2,6,6‐Tetramethylpiperidinyl‐N‐oxy (TEMPO) is a robust nitroxide radical molecule under ambient conditions. We found that the TEMPO derivatives act as a proton acceptor to form an intermolecular hydrogen‐bonding complex with many kinds of phenol or urea derivatives. ORTEP analysis of the crystals of TEMPO with the phenol derivatives indicated that hydrogen bonding could be formed between the oxygen of the nitroxide and the phenolic proton and the NO bond of the hydrogen‐bonded TEMPO was lengthened in comparison to that of the free NO bond. The formation constant of the hydrogen‐bonding complex of TEMPO with the phenol or urea derivatives in a chloroform solution was spectroscopically determined by IR to be 10–100 M−1. Hydrogen bonding of the thelechelic bis‐TEMPO derivatives with thelechelic bis‐phenol or bis‐urea derivatives provided a supramolecular structure. The estimated molecular weights of the supramolecules in the chloroform solution, based on DOSY‐NMR spectroscopy, were 3000–4000. The potential of the nitroxide radical's supramolecule as a new functional material is also described.