FUEL PROCESSING TECHNOLOGY
·
2019
·
IF 4.507
Tao Xie,Jing-Pei Cao,Chen Zhu,Xiao-Yan Zhao,Ming Zhao,Yun-Peng Zhao,Xian-Yong Wei
Selectively cleaving the C O bonds in lignin to produce aromatic products are challenging problems. Currently, catalytic hydrogenolysis of C O bonds in lignin requires harsh conditions. Herein, selectively cleaving C O bond of benzyl phenyl ether (BPE) was studied over Pd/AC, Ru/AC and Ni/AC. Among these catalysts, Pd/AC efficiently cleaved C O bond in BPE under super mild conditions (25 °C, 2 h and 0.1 MPa H 2 ). The products were toluene and phenol without hydrogenation of the aromatic ring . The main competitive step of hydrogenolysis and hydrogenation is sensitive to reaction temperature over Pd catalyst. A mild temperature is preferred for hydrogenolysis, since the H species nearby the oxygen atom are more strongly adsorbed than nearby the benzene rings . With the different H-donor solvents, the highest conversion of BPE was obtained in isopropanol. Based on the experiments, the reactions occurred via cleavage of the C aliphatic -O bond in BPE and the synergetic effects between the H from absorbed H 2 on the surface of the Pd and the intermediates radicals of benzyl and phenoxy should be the key points to such an optimum result.
研究领域:
化学工程
·
催化科学
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2021
·
IF 3.196
Simin Liu,Defei Yin,Wei Li,Dongzhi Liu,Xueqin Zhou
In this paper, three new compounds were synthesized by introduction of benzyloxy group to phenylethyl phenylacetate ( PPA ) and shorting the flexible ester linker. NMR spectra and mass spectra are achieved to confirm the structure of the compounds. The solid-liquid and liquid-solid phase change behaviors of PPA and these three compounds were explored by direct observation and differential scanning calorimetry (DSC) measurements. It was found that all four compounds would form supercooled liquids during a heating-cooling cycle. The supercooling degree is as large as 44 °C or above. The effects of benzyloxy group and the flexible linker on the phase transition processes as well as the supercooling degrees were discussed in detail with the computational optimized geometry of isolated molecules. It was revealed that the dihedral angles between adjacent phenyl rings play a significant role in tuning their phase transition temperatures. This work also discovers the high enthalpies of PPA derivatives and analogues in both solid-liquid and liquid-solid phase transition processes, making them great potentials for the thermal energy control of appropriate working temperature regions.
研究领域:
材料科学
·
物理化学
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DOI
高影响因子
SN Applied Sciences
·
2021
·Vol. 3
·期 3
·1-9
·
IF 0
Ma Yinzheng,Wen Yingying,Chen Jinping,Zhang Yunxia,Zhang Haiying,Sui Jinlei,Yi Guohui,He Xiaowen
A rapid and sensitive headspace gas chromatography-mass spectrometry (HS-GC–MS) method was established for the determination of benzyl isothiocyanate (BITC) in the peel, pulp, and seeds of Carica papaya Linn. Tween 80 solution with a concentration of 0.002% ( w/v ) was chosen as a headspace medium for solving the poor solubility of BITC in water without using organic solvents and ensuring high headspace efficiencies. Extraction parameters had been evaluated and optimized by using an orthogonal design with an OA 9 (3 4 ) table. Optimal headspace conditions were obtained when vials were equilibrated at 80 °C for 20 min at a stirring speed of 375 rpm. The calibration curve obtained by using GC–MS was linear in a concentration range of 10–320 ng/mL. The recoveries of peel, pulp, and seeds ranged from 97.3 to 100.6% with RSDs less than 3.0%. The method is simple, rapid, sensitive, and environmentally friendly. It is suitable for analyzing BITC in papaya fruit and is expected to have important application potential in the extraction of water-insoluble volatile components in foods, plants, medicines, and other samples.
研究领域:
食品科学
·
分析化学
·
植物学
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产品关联
DOI
Insects
·
2025
·Vol. 16
·期 4
·371
·
IF 2.9
Yini Wang,Yahong Wang,Changfang Zhou
Simple SummaryThe aquatic macrophyte watershield,Brasenia schreberiGmel., with its young buds coated in a thick mucilage served as a famous vegetable, has been cultivated in China for a long time. However, its production has been threatened by a pest,Galerucella birmanicaJacoby. This study investigated the population dynamics ofG. birmanicathroughout the entire growth season ofB. schreberifrom May to November and identified the aggregation behavior of the pest, with a preference for severely chewed leaf areas. Further analysis revealed that it was 2-phenylethyl isothiocyanate released from the damaged leaves that attractedG. birmanica. Our findings provide valuable insights for pest management inB. schrebericultivation fields, and the attractant effect of 2-phenylethyl isothiocyanate onG. birmanicaoffers a new perspective for the development of attractants for this insect.The aquatic vegetableBrasenia schreberiGmel. (Nymphaeales: Cabombaceae), widely cultivated in China, faces severe challenges from pest disturbances. With a field investigation,G. birmanicaoccurred for several generations in theBraseniamono-cultivation system. The first visual peak on leaf surfaces appeared in July, with eggs, larvae, pupae and adults all being recorded. The highest number of flying adults were trapped in August in reverse to the absence of beetles on leaves, followed by an extraordinary high number of eggs in September.G. birmanicaexhibited a conspicuous aggregation in distribution, with severely chewed areas having aG. birmanicaabundance 21.6 times that of the non-chewed areas. Laboratory studies with GC–MS and two-choice tests revealed four volatiles significantly discrepant in contents released from chewed/intact leaves: cis-3-hexenyl acetate (917.33 ± 29.56 vs. 604.034 ± 23.24 ng, chewed vs. intact), 2-phenylethyl isothiocyanate (595.37 ± 28.42 vs. 356.00 ± 13.44 ng), undecane (771.44 ± 34.72 vs. 1003.28 ± 47.88 ng) and methyl salicylate (1079.84 ± 49.39 vs. 532.11 ± 18.23 ng); among them, 2-phenylethyl isothiocyanate could significantly attractG. birmanicaadults. Our study suggests thatG. birmanicacan be a severe threat to mono-cultivatedB. schreberi, whereas the damaged leaves may sacrifice themselves by attracting the beetles with an herbivore-induced volatile, thus protecting the whole plant population from pest disturbance.
研究领域:
生态学
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昆虫学
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植物保护
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产品关联
DOI
PubMed
高影响因子
BIOCATALYSIS AND BIOTRANSFORMATION
·
2021
·
IF 2.181
Lu Dong,Shujuan Qi,Jianwei Jia,Yun Zhang,Yunfeng Hu
Bacillus sp. DL-1 was isolated from the deep sea of the Western Pacific Ocean and behaved very good resistance to NaCl. The extracellular proteases of Bacillus sp. DL-1 were found to exhibit excellent enantioselectivity for the kinetic resolution of (±)-1-phenylethyl acetate. To improve the stability of the enzyme, the immobilized extracellular proteases were preparated by using 60 g kieselguhr and 1-L crude fermentation broth containing extracellular proteases of Bacillus sp. DL-1, shaking at 25 °C, 200 r/min for 10 h. Every gram of kieselguhr adsorbed 25.7 mg extracellular protease and the enzymatic activity recovery was 79.86%. The immobilized proteases preserved about 35.8% of its activity after 6 repeated uses, which were also used as biocatalyst to asymmetrically hydrolyse (±)-1-phenylethyl acetate for the preparation of (R)-1-phenylethanol and (S)-1-phenylethyl acetate with high optical purities. The effects of pH, temperature, enzyme concentration, substrate concentration, reaction time and additives (metal ions/surfactants) on the resolution were investigated by single factor experiments. Under the optimal reaction conditions (10 mM (±)-1-phenylethyl acetate, 40 mg/mL immobilized extracellular proteases, pH 7.5 (Tris-HCl), 5% (v/v) methanol and 45 °C for 2 h), (R)-1-phenylethanol was generated with the e.e.p being > 97%, and the yield being 53%, respectively. Analogously, under the optimal reaction conditions (10-mM (±)-1-phenylethyl acetate, 360 mg/mL immobilized extracellular proteases, pH 6.0 (PB), 5% (v/v) DMSO and 35 °C for 1.5 h), (S)-1-phenylethyl acetate was generated with the e.e.s being over 99% and the yield being 79%, respectively. Compared with the extracellular proteases from Bacillus sp. DL-2, the immobilized extracellular proteases from Bacillus sp. DL-1 exhibited higher hydrolytic activity and could asymmetrically hydrolyse (±)-1-phenylethyl acetate by using higher substrate concentrations, shorter reaction times to obtain higher yields. Notably, the extracellular proteases of Bacillus sp. DL-1 were demonstrated to behave the same enantio-preference as those of most other reported esterases/lipases. Proteases from deep-sea Bacillus sp. DL-1 are promising biocatalysts for the synthesis of valuable chiral chemicals.
研究领域:
生物催化
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酶学
·
微生物学
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有机化学
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产品关联
DOI
高影响因子
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
·
2022
·Vol. 120
·期 1
·e2209339120
·
IF 12.779
Fei Qiao,Yuedong He,Yuhao Zhang,Xuefei Jiang,Hanqing Cong,Zhiming Wang,Huapeng Sun,Yibei Xiao,Yucheng Zhao,Peter Nick
Cephalotaxines harbor great medical potential, but their natural source, the endemic conifer Cephalotaxus is highly endangered, creating a conflict between biotechnological valorization and preservation of biodiversity. Here, we construct the whole biosynthetic pathway to the 1-phenethylisoquinoline scaffold, as first committed compound for phenylethylisoquinoline alkaloids (PIAs), combining metabolic modeling, and transcriptome mining of Cephalotaxus hainanensis to infer the biosynthesis for PIA precursor. We identify a novel protein, ChPSS, driving the Pictet–Spengler condensation and show that this enzyme represents the branching point where PIA biosynthesis diverges from the concurrent benzylisoquinoline-alkaloids pathway. We also pinpoint ChDBR as crucial step to form 4-hydroxydihydrocinnamaldehyde diverging from lignin biosynthesis. The elucidation of the early PIA pathway represents an important step toward microbe-based production of these pharmaceutically important alkaloids resolving the conflict between biotechnology and preservation of biodiversity.
研究领域:
植物生物化学
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药用植物学
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生物技术
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保护生物学
✓ 已验证
DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2021
·
IF 3.757
Tian Tian,Xiaohong Tong,Yue Yuan,Bo Lyu,Dengzhen Jiang,Wenyu Cui,Xiaoyi Cheng,Liang Li,Yang Li,Lianzhou Jiang,Huan Wang
The stability and digestibility of food emulsions are affected by the various sources and structural characteristics of emulsifiers. Chitosan, Arabia gum, soy protein isolate (SPI), and soybean protein isolate-phosphatidylcholine (SPI-PC) were used as natural emulsifiers in this study, and a 10 % (v/v) MCT oil phase (containing 10 methyl g/mL benzyl isothiocyanate (BITC)) was used for the preparation of oil in water nanoemulsions. The stability of nanoemulsions and their in vitro digestion characteristics were determined using dynamic light scattering, scanning electron microscopy, differential scanning calorimetry, and ultraviolet-visible spectrophotometry. The average particle size and potential of chitosan and Arabia gum nanoemulsion changed significantly under extreme environmental conditions, and their stability was poor. SPI-PC nanoemulsion exhibited a more stable transport system. The type of emulsifier has a significant effect on the release of free fatty acids and BITC digestibility. SPI-PC nanoemulsion have higher BITC bioavailability when compared to other emulsifiers. The results showed that natural emulsifiers could stabilize the emulsion, but there was a significant difference in their stability. The SPI-PC composite emulsifier could produce a nanoemulsion that is relatively stable, safe, and high in bioavailability.
研究领域:
食品科学
·
营养学
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产品关联
DOI
高影响因子
FOOD HYDROCOLLOIDS
·
2023
·
IF 10.7
Yue Huang,Jianan Liu,Zhaolun Li,Zechen Cao,Hongshun Hao,Jingran Bi,Hongman Hou,Hongyan Wu,Gongliang Zhang
To effectively utilize the potent antibacterial capacity of benzyl isothiocyanate (BITC), attempts have been made to apply it in the natural biopolymeric film by solving its high volatility. In this study, we encapsulated BITC in the carrier β-cyclodextrin (βCD) to form an inclusion complex to protect BITC from volatilization and then introduced the complex to κ-carrageenan (KC) to fabricate an antibacterial food packaging film. The addition of the BITC-βCD complex enhanced the storage modulus and promoted a denser network structure formation for KC hydrogel by rheological measurements and microstructure observations, respectively. In terms of antibacterial capacity, BITC-βCD-KC film displayed favorable antibacterial potential against both Staphylococcus aureus and Listeria monocytogenes after co-incubation for 18 h, with the inhibition zone diameters of 25.7 mm and 16.7 mm, respectively. As an active packing material, the BITC-βCD-KC film exhibited a sustained inhibition effect against the proliferation of these two bacteria on the chicken meat surface at 25 °C. Moreover, the chicken breasts packaged with BITC-βCD-KC film had a total viable count of 4.7 Log CFU/g, obviously lower than that of the unpackaged sample (9.8 Log CFU/g) after storage at 4 °C for 8 days. These results suggested that the KC film with the BITC-βCD inclusion complex might have promising potential as an antibacterial food packaging material for food preservation.
研究领域:
食品科学
·
材料科学
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DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2021
·
IF 5.541
Xurui Zhang,Zezhou Chen,Zhenyu Liu,Qingya Liu
Naphtha cracking for the production of olefins is extremely energy intensive, accounting for 40 % of the total energy consumption in the petrochemical industry. Since the main energy barrier of naphtha cracking is the radical initiation step, this work proposed an approach to induce the naphtha cracking by adding bibenzyl as a novel radical initiator. To verify the induction effect of bibenzyl on naphtha cracking, the conversion of naphtha model compound n -hexane with and without bibenzyl was investigated in 0.5–30 min at 400 °C and 440 °C and the products were analyzed in detail. It was found that the addition of bibenzyl increases the conversion of n -hexane from 0.39 wt.% to 5.91 wt.% at 400 °C and from 3.41 wt.% to 31.45 wt.% at 440 °C for 30 min. The gaseous products consisting of C 1 -C 4 alkanes and α-olefins showed an obviously increase after bibenzyl addition. The reaction pathways of benzyl radicals generated from the dissociation of C al -C al bonds of bibenzyl include abstracting H atoms from bibenzyl and n -hexane, and coupling with alkane radicals generated from n -hexane cracking. The incremental quantity of gaseous products is linear with the quantity of benzyl radicals. The slopes, reflecting the number of accelerated radical propagation reactions between molecules induced by per benzyl radical, increase with the decrease of bibenzyl. When the mass ratio of bibenzyl to n -hexane is 1:100, the average numbers of accelerated radical propagation reactions between molecules per benzyl radical are 185.74 and 186.38 at 400 °C and 440 °C, respectively.
研究领域:
化学工程
·
石油化工
✓ 已验证
产品关联
DOI
高影响因子
Food Bioscience
·
2024
·
IF 4.8
Liu Wenwen,Lin Songyi,Song Liang,Wang Siyu,Nakamura Yoshimasa,Tang Yue
In this research endeavor, a novel emulsion delivery system was devised to enhance the retention of the fat-soluble active substance known as benzyl isothiocyanate (BITC). Fish skin gelatin (FSG) and pectin (PEC) were chosen as complex emulsifiers and collectively referred to as FSG-PEC. The interaction between FSG and PEC was examined by turbidity, flourier transform infrared, fluorescence, ultraviolet, methylene blue, and molecular docking. Emulsification activity, emulsification stability, contact angle, appearance structure, average particle size, zeta potential, oil droplet distribution, and retention rate of the encapsulated BITC, were evaluated to determine the optimal concentration ratio of the FSG-PEC complex for effectively safeguarding BITC. The results showed that the turbidity of FSG and PEC was minimal at pH 7, indicating relative stability of the complex. The primary molecular forces between FSG and PEC were electrostatic and hydrogen bond interaction. The interfacial stability, emulsifying activity and stability of FSG-PEC complex at a 2:1 ratio surpassed those of other ratios. Consequently, this optimal ratio was utilized to prepare FSG-PEC emulsion delivery system containing BITC. The resulting emulsion, stored for 14 days at 4 °C, demonstrated compelling attributes with a particle size of 433.33 ± 1.12 nm, a potential of −32.87 ± 0.35 mV, and a BITC retention rate of 59.87 ± 0.65%. The combination of the indicators finally concluded that 2:1 was the optimal ratio to construct the FSG-PEC complex emulsion delivery system. This study constitutes an initial exploration of the interaction dynamics between FSG and PEC, providing a theoretical foundation for subsequent applications.
研究领域:
食品科学
·
生物化学
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DOI
高影响因子
TOXICOLOGY LETTERS
·
2011
·
IF 3.581
Zhaobin Zhang,Chengxia Jia,Ying Hu,Libei Sun,Jian Jiao,Liang Zhao,Desheng Zhu,Jun Li,Yonglu Tian,Huicheng Bai,Ruobao Li,Jianying Hu
Salicylate esters (SEs), a class of chemicals extensively used as flavor and fragrance additives in foods, beverages and a wide variety of consumer products, are suspected to have estrogenic activity based on chemical analysis of in silica molecular docking. We evaluated the estrogenic potentials of phenyl salicylate (PhS), benzyl salicylate (BzS), phenethyl salicylate (PES), ethyl salicylate (ES) and methyl salicylate (MS) using an in vitro human estrogen receptor α (hERα)-coactivator recruiting assay and in vivo immature rodent uterotrophic bioassays. We found that PhS, BzS and PES showed obvious in vitro hERα agonistic activities; BzS in particular exhibited a higher estrogenic activity compared to bisphenol A (BPA). The uterine weights were significantly increased in mice treated with 11.1, 33.3, 100 and 300 mg/kg/day BzS and 33.3 mg/kg/day PES and rats treated with 3.7, 11.1, 33.3 and 100 mg/kg/day BzS for 3 days ( P < 0.05). Finally, we transformed the daily intakes and the dermal exposures of SEs in the real world into estradiol equivalent concentrations (EEQs). We found that the EEQ of BzS daily intake in consumers in the U.S. and the EEQs of dermal BzS and PES exposure among high-volume users worldwide were higher than the maximum secure daily estradiol intake recommended by the U.S. Food and Drug Administration (FDA). In particular, the EEQ for dermal BzS exposure was up to 162 ng EEQ/kg, which is 3.3 times higher than the maximal acceptable daily E 2 intake recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA).
研究领域:
毒理学
·
环境科学
·
食品科学
·
药理学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2016
·Vol. 21
·期 5
·555
·
IF 2.465
Zhongxiu Zhang,Xiaohui Wang,Wanqing Yang,Juan Wang,Cong Su,Xiao Liu,Jun Li,Yunfang Zhao,Shepo Shi,Pengfei Tu
Five 2-(2-phenylethyl)chromones including a new one, (5S,6R,7S,8R)-5,8-dichloro-6,7-dihydroxy-2-phenylethyl-5,6,7,8-tetrahydro-4H-chromen-4-one (1), and four known ones (2–5), were isolated from 150 mM NaCl-elicitedAquilaria sinensiscell suspension cultures. In addition, three feruloyl amides (6–8), six nucleosides (9–14), (+)-syringaresinol (15), indole-3-carboxaldehyde (16), and two glycosides (17–18) were also obtained. The structures were unambiguously identified by analysis of their UV, IR, NMR, and HRESIMS data. The absolute configuration of the new 2-(2-phenylethyl)chromone (1) was established by a dimolybdenum tetraacetate-induced circular dichroism experiment. Compared to un-elicited cell lines, the appearance of 2-(2-phenylethyl)chromones in NaCl-treated cells occurred on the 3rd and 5th days of their treatment. 2-(2-Phenylethyl)chromones, feruloyl amides, nucleosides, and lignins have been reported to be closely related to plant defense; therefore, the identification of these compounds from NaCl-elicitedA. sinensiscell suspension cultures would be useful for further exploring the mechanism of agarwood formation.Keywords:2-(2-phenylethyl)chromone;induced circular dichroism;Aquilaria sinensis;agarwood;cell suspension cultures;sodium chloride elicitation
研究领域:
植物学
·
天然产物化学
·
药用植物研究
✓ 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）