JOURNAL OF ORGANIC CHEMISTRY
·
2019
·
IF 4.745
Shaofeng Wu,Jianyu Dong,Dan Zhou,Wan Wang,Long Liu,Yongbo Zhou
A H3PO3-catalyzed alkylation of phenols with alkenes is achieved in a facile, efficient, and selective manner. The reaction shows a unique selectivity, i.e., excellent regioselectivity, thorough suppression of overalkylation, without alkylation of a simple phenyl ring, and can selectively provide ortho-, meta-, or para-alkylated phenol derivatives in good to excellent yields. This feature along with mild reaction conditions, sensitive functional group tolerance, and scale-up synthesis and late modification of phenolic bioactive compounds make it an ideal and practical alternative for the modification of phenols.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 123
·101507-101518
·
IF 3.84
Huihui Ti,Jinjie Guo,Ruifen Zhang,Zhencheng Wei,Lei Liu,Yajuan Bai,Mingwei Zhang
In view of the fact that different types of processed rice contain different tissue fractions, the present study quantified free and bound phenolic profiles and antioxidant activity in the pericarp, aleurone layer, embryo and endosperm fractions of japonica and indica whole brown rice. Significant differences were found in the total phenolic content, oxygen radical absorbance capacity (ORAC) and cellular antioxidant activity (CAA) of the different fractions. The ratios of free and bound phenolics to total phenolics varied between the fractions. Thirteen individual phenolic compounds (gallic, protocatechuic, hydroxybenzoic, chlorogenic, vanillic, caffeic, syringic, isoferulic, coumaric and ferulic acids, as well as catechin, epicatechin and quercetin) were detected in both free and bound forms. The contributions of the pericarp, aleurone layer and embryo fractions to whole brown rice were 13.0%, 28.5% and 8.8% for total phenolics, 14.1%, 29.7% and 9.1% for total flavonoids, 18.2%, 38.0%, and 11.1% for total ORAC values and 14.6%, 38.0%, and 16.9% for CAA values, respectively. These findings indicate that the phenolics in brown rice can be concentrated by processing different fractions or by milling to different levels because of the uneven distribution of chemical constituents.
研究领域:
食品科学
·
植物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF FOOD PROCESSING AND PRESERVATION
·
2022
·Vol. 46
·期 7
·e16679
·
IF 2.609
Nan Chen,Zi-Jian Feng,Hao-Xiang Gao,Qiang He,Wei-Cai Zeng
Four phenols (protocatechuic acid, ellagic acid, naringin, and tannic acid), could affect the particle size and microstructures of potato starch, while the action sequence was as: tannic acid > naringin > ellagic acid > protocatechuic acid. Meanwhile, all phenols could decrease the thermal stability of potato starch and changed its crystallinity. In addition, hydrogen bonds were determined as the main molecular force between phenols and potato starch. Furthermore, molecular dynamics simulation indicated that phenols could significantly affect the spatial configuration of starch molecules by changing the formation of hydrogen bonds, and phenols with more hydroxyl groups and higher molecular weight exhibited stronger binding effects than simple phenols. All present results suggested that the hydroxyl groups amount and molecular weight of phenols could affect their effects on starch molecules, so as to significantly affected the properties of potato starch, which showed the potential application in chemical and food industries. Novelty impact statement Phenols affected the properties of potato starch and changed the spatial configuration of starch molecules by a hydrogen bond. Phenols action sequence was: tannic acid > naringin > ellagic acid > protocatechuic acid, and more hydroxyls and higher molecular weight promoted the effects of phenols on starch.
研究领域:
食品科学
·
分子生物学
✓ 已验证
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Jijun Guan,Liwei Wang,Fugang Xu,Guangran Ma
Ratiometric electrochemical probes are vital for reliable sensing but often suffer from complex preparation, reference molecule leakage, and single function. To address these limitations, this study reports a flower-like Cu-doped zeolite imidazolate framework (Zn 0.5 /Cu 0.5 /Co-ZIF) prepared at room temperature via simple stirring. This material acts as both an electrode material and a robust ratiometric probe for detecting catechol (CC) and acetaminophen (AP). Compared with pristine Zn/Co-ZIF, Cu doping confers several advantages: transforming lamellar Zn/Co-ZIF into a flower-like structure for enhanced electron and mass transfer; significantly improving redox current of CC/AP for high sensitivity; and generating a stable Cu-based redox signal as an internal reference, improving accuracy. The sensor achieved wide linear ranges (CC: 0.5–150 μM; AP: 0.2–300 μM) and low detection limits (CC: 0.12 μM; AP: 0.04 μM) for determination of phenol compounds. Compared to single-signal assay, the ratiometric approach showed lower RSDs and superior linear correlations. The sensor also achieved satisfactory simultaneous detection of CC and AP, along with accurate quantification in lake water samples. This work presents a facile strategy for a MOF based reference probe, offering a promising platform for stable and accurate ratiometric electrochemical sensors.
研究领域:
生物传感
·
分析化学
·
纳米材料
·
环境监测
·
电化学检测
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2024
·
IF 5.8
Xiongjian Du,Shubin Wu
The synthesis of phenol via pyrolysis of lignin can be envisaged as a prospective approach for the high-value utilization of lignin, Herein, we describe an in-depth investigation of the selective modification of lignin to effectively adjust the distribution of lignin pyrolysis products. We found that hydroxypropyl modification of lignin can facilitate the elimination of methoxy from the lignin macromolecule and improve the selectivity of phenol products. In addition, increasing the carbon number of the lignin side chains causes polymerization of pyrolysis products, which is unfavorable for the synthesis of fine chemicals via lignin pyrolysis. Conversely, an increase in lignin side-chain hydroxyl content can lead to more liquid-phase products from lignin pyrolysis, and the selectivity of phenol and its congeners will also increase. As a result, the yield of liquid products obtained via pyrolysis of lignin modified via selective oxyalkylation can reach 52 %, and the relative content of phenol and its homologs can reach 45.2 %.
研究领域:
生物质化学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2021
·
IF 3.975
Fada Li,Bo Chen,Yu Han,Yiwen Cao,Xiaoxue Hong,Mancai Xu
Phenol, catechol , and pyrogallol were employed as the hydrogen-bond donors to chemically modify the commercial adsorbent Amberlite XAD16 via Friedel-Crafts reaction, and three phenols-modified XAD16 were named as, XAD16-Ph(OH), XAD16-Ph(OH) 2 , and XAD16-Ph(OH) 3 respectively. The resulting polymers had porous parameters including Brunauer-Emmett-Teller (BET) surface area ( S BET ) and total pore volume ( V total ) similar to Amberlite XAD16, however the oxygen (O) content was remarkably increased after the Friedel-Crafts reaction in the presence of anhydrous FeCl 3 as catalyst. The synthesized polymers had larger equilibrium adsorption capacities toward ε-caprolactam ( q max = 69.2 mg/g) than Amberlite XAD16 due to the enhanced adsorption contributed by hydrogen bonding between the phenolic hydroxyl groups uploaded on the polymers and the carbonyl of ε-caprolactam (CPL). Experimental data indicated that the removal percentage of CPL reached 93.2% at a concentration of 0.2840 g/25 mL for XAD16-Ph(OH) 2 while the equilibrium data were fitted by the Freundlich and Langmuir models, and the kinetic data were described by the pseudo-second-order rate equation and characterized by the micropore diffusion model.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Xinyue Wang,Yingnan Sun,Lu Yang,Qingkun Shang,Dan Wang,Tongtong Guo,Yihang Guo
Photocatalysis is one of the effective strategies to eliminate various organic pollutants in water body. In this paper we have prepared a series of new composite photocatalysts to degrade phenol and norfloxacin under visible light irradiation. They were [Fe II (dpbpy) 2 (H 2 O) 2 ]/TiO 2 , [Fe II (dpbpy)(phen) 2 ]/TiO 2 and [Fe II (dpbpy)(bpy) 2 ]/TiO 2 (dpbpy: 2,2′-bipyridine-4,4′-diphosphoric acid, phen: 1,10-phenanthroline, bpy: 2,2-bipyridyl). The results show that their photocatalytic performance and cyclic stability are much better than that of pure TiO 2 or P25. Phenol can be degraded almost completely and the active groups or substituents of norfloxacin (NOR) can be destroyed also, which greatly reduced the biological toxicity of phenol and norfloxacin in water. The possible mechanisms of improving the photocatalytic activity and stability of TiO 2 by using Fe-complex are proposed based on free radical capture test and density functional theory calculation. It is clearly that the interfacial interaction between Fe-complex and titanium dioxide directly affects the photocatalytic activity and stability of the composite photocatalyst. The conjugated structure of the complexes plays a crucial role.
研究领域:
环境科学
·
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2016
·
IF 4.012
Mazloom Shah,Fan Zhang,Ashfaq Ahmad
The catalytic conversion of substituted and unsubstituted cyclohexanones to the corresponding enones and aromatic alcohol catalyzed by Pd, Pd-1, Pd-cube, Cu, Ni, Ag@Pd and Ni-Sn nanocatalysts has been studied in the presence of O 2 as the oxidant without using any additives i.e. acid or base or ligand. The optimization of experimental parameters for dehydrogenation of cyclohexanones was established to achieve maximum yield of the product by using Pd nanocatalyst. The conversion of cyclohexanone, cyclohexenone, 3-methyl cyclohexanone and 3-methyl cyclohexenone catalyzed by Pd nanocatalyst at 80 °C, 10 atm O 2 pressure after 24 h, led to a 79%, 49%, 62% and 25% yields of desired products, respectively. Then, the conversion of substituted and unsubstituted cyclohexanones investigated in the presence of various nanocatalysts i.e., Pd-1, Pd-cube, Cu, Ni, Ag@Pd and Ni-Sn nanoparticles and was compared their percentage yields.
研究领域:
化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2019
·
IF 3.714
Haiying Cai,Qi Zhang,Lingzhi Shen,Jie Luo,Ruiyu Zhu,Jianwei Mao,Minjie Zhao,Chenggang Cai
The polyphenolic compounds in wines are beneficial to human health. To better understand the effect of different factors on the phenolics and antioxidant activities of wine during rice wine fermentation, 6 rice materials and 7 rice wine starters from rural areas were used to ferment Chinese rice wine. The results showed that black rice and the starter O4 were preferred for the optimum polyphenolic content and antioxidant activity, respectively. In addition, the results indicated that the polyphenolics of the rice wines were mainly derived from their plant materials and that various rice materials could result in drastically different wine quality. In contrast, the total polyphenol contents could be less significantly changed by using different starters. The antioxidant activity results of these fermented wines were consistent with the results of the total polyphenol contents. The rice wines produced using 6 different rice materials were significantly different in antioxidant activity measured by ABTS and FRAP assay . Similar to the results of the total polyphenol content and the antioxidant activity, the wine samples with different rice materials showed significantly different polyphenolic profiles compared with those of the rice wine group with different starters. These results suggested that rice materials and starters have different effects on polyphenol extraction and conversion of rice wines.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
CELLULOSE
·
2021
·Vol. 28
·期 7
·4397-4409
·
IF 5.044
Ni Shuzhen,Liu Na,Fu Yingjuan,Gao Hailong,Qin Menghua
Abstract Herein, a great potential approach initiated by laccase is applied to graft the biopolymers (chitosan and phenols) onto the unbleached Kraft pulp fibers to enhance the hydrophobicity and strength. The results showed that the chitosan and laccase/phenols exhibited a synergistic action on the significant improvement of the hydrophobicity of the KP pulp fibers. Compared with the base paper, a high sizing degree value (227.08 s) was achieved when the fibers were treated by the laccase/4-hexyloxyphenol/chitosan (Lac/HP/CTS) system. The water retention value of the corresponding KP fibers reduced from 176.8 to 171.3%, and the Kappa number of treated fibers increased from 26.8 to 29.3, confirming the successful graft of HP onto the fibers. The effect of the reaction parameters, including the temperature, pH, HP and chitosan dosage, reaction time and pulp suspension consistency on the strength and hydrophobicity was investigated. pH value was found as the most remarkable factor influencing the sizing degree and gave a highest sizing value (506.2 s) at pH 5.5. The strength performance presented an opposite trend against the hydrophobicity, since the number of formed hydrogen bonds is the least when the hydrophobicity is the best. This work is extremely significant for providing valuable reference on improving the hydrophobicity and strength performance of papers through a green and biological way. Graphic abstract
研究领域:
制浆造纸科学
·
生物技术
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Chao Ding,Qiang Liu,Peng Li,Yongsheng Pei,Tingting Tao,Yan Wang,Wei Yan,Guofeng Yang,Xiaolong Shao
Utilization of phenolic compounds in rice husk and bran is important for improving the functionality of rice by-products. Eight rice varieties planted in different area were selected to analyze the phenolic compounds distribution of fractions in Japonica and Indica rice by using UPLC-MS method. A total of 12 phenolic compounds were identified in all rice varieties. Ferulic acid, gallic acid, protocatechuic acid and syringic acid were the dominant phenolic compounds in rice bran, while p-Hydroxybenzaldehyde was the main phenolic compounds existed in rice husk (14.46–23.72 µg·g −1 ). Bran and husk fractions provide more than 90% of phenolic compounds and antioxidant activity of whole rice. Regardless of the planting environmental effects, Japonica rice has significant higher phenolic compounds and antioxidant activity than Indica rice (P < 0.05). Therefore, it can be concluded that the distribution of phenolic compounds were strongly correlated with the rice varieties and fractions.
研究领域:
食品科学
·
植物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2016
·Vol. 9
·期 4
·282
·
IF 2.728
Dawei Li,Jun Zang,Jin Zhang,Kelong Ao,Qingqing Wang,Quanfeng Dong,Qufu Wei
Carbon xerogel-zinc oxide (CXZnO) composites were synthesized by a simple method of sol-gel condensation polymerization of formaldehyde and resorcinol solution containing zinc salt followed by drying and thermal treatment. ZnO nanoparticles were observed to be evenly dispersed on the surfaces of the carbon xerogel microspheres. The as-prepared CXZnO composites were mixed with laccase (Lac) and Nafion to obtain a mixture solution, which was further modified on an electrode surface to construct a novel biosensing platform. Finally, the prepared electrochemical biosensor was employed to detect the environmental pollutant, catechol. The analysis result was satisfactory, the sensor showed excellent electrocatalysis towards catechol with high sensitivity (31.2 µA·mM−1), a low detection limit (2.17 µM), and a wide linear range (6.91–453 µM). Moreover, the biosensor also displayed favorable repeatability, reproducibility, selectivity, and stability besides being successfully used in the trace detection of catechol existing in lake water environments.Keywords:carbon xerogel;ZnO;laccase;phenolic biosensor
研究领域:
材料科学
·
环境科学
·
生物传感
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）