INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2015
·
IF 2.858
Jie Xu,Li-Li Xu,Qin-Wei Zhou,Shu-Xian Hao,Tao Zhou,Hu-Jun Xie
In the present study, purification and characterization of enzymatic hydrolysates of polysaccharide from Enteromorpha prolifera (HPE) are described. HPE was sequentially purified by DEAE Cellulose-52 chromatography and Sephadex G-100 chromatography to afford three fractions, namely, PHPE1, PHPE2, and PHPE3. Molecular weights of these three fractions were measured to be 103, 45.4, and 9.8 kDa, respectively, using high performance gel permeation chromatography (HPGPC). The three fractions were evaluated for their antioxidant activities by determining their ability to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and superoxide anion radicals. PHPE2 was found to possess the strongest scavenging ability. GC–MS analysis indicates that PHPE2 is mainly composed of mannose , xylose , and glucose.
研究领域:
海洋生物学
·
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Yanxiao Chen,Huifen Zhang,Weifeng Dai,Cheng Xiang,Shiyun Jiao,Baocai Li,Mi Zhang
Montan resin removal and oxidation bleaching are two key procedures for preparing refined montan wax (RMW) from lignite and significantly affect the wax’s color appearance. However, due to the large content differences of crude montan wax (CMW) in lignite and montan resin (MR) in CMW, the influence of residual MR in CMW on the character and performance of RMW is unknown. In this study, CMWs with different amounts of residual MR were prepared as raw materials and oxidized into RMWs under the same bleaching conditions. The main physicochemical properties of these RMWs showed that as the residual MR content in CMW increased, the RMW color deepened and the friability and saponification values increased, but the melting point, acid value, and hardness decreased. Meanwhile, the chemicals present in different RMWs were analyzed by gas chromatography–mass spectrometry (GC-MS), and cluster detection showed the content and composition of chemicals in RMWs produced from CMWs with different residual MR contents were significantly different. PCA analysis showed that residual MR in CMW was positively correlated with the friability and saponification value but was negatively correlated with the final melting point, microhardness, and acid value. This work indicates that the residual MR in CMWs has a strong but different influence on the appearance and performance of RMW and provides some basis for further optimization and improvement of refinement techniques for various RMWs used in different areas.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Biomass Conversion and Biorefinery
·
2024
·
IF 3.5
Liang Miao,Wang Yiqun,Dai Shuiping,Hong Liu,Li Ruili,Xu Zhenyu,Su Jiakun,Zhang Junsong
Cigar is a kind of air-dried tobacco raw material with different physical structures and chemical compositions compared with flue-cured tobacco. The pyrolysis and thermal release characteristics of cigar tobacco are important for advancing their use in heat-not-burn cigarette. In this study, the thermal release behavior of cigar tobacco with different glycerol additions under heating conditions was analyzed by thermogravimetric technique as well as a self-built infrared rapid heating furnace combined with GC–MS analysis. The results showed that the thermal weight loss process of cigar tobacco could be divided into three stages. The addition of glycerol exhibited significant impact on pyrolysis process, especially in the stage II, accompanied by a decrease in T max , an increase in DTG max , and weight loss at this stage. Thermal release kinetic analysis of stage II by Coats-Redfern method showed an increased activation energy and pre-exponential factor. With the amount of glycerol addition increasing, the total aroma components released from cigar tobacco showed a trend of first increasing and then decreasing at both heating rates, and reached the highest level when the glycerol addition amount was 20%. By means of multi-factor analysis of variance, the significance of heating rate and glycerol addition as well as the optimum combination between them that could maximize the release of various types of aroma components was determined. This study may be beneficial for the reasonable utilization of cigar tobacco in related products.
研究领域:
烟草科学
·
热化学分析
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2017
·
IF 3.981
Fengli Chen,Jia Jia,Qiang Zhang,Huiyan Gu,Lei Yang
In this work, a modified technique was developed to separate essential oil from the fruit of Amorpha fruticosa using microwave-assisted hydrodistillation concatenated liquid-liquid extraction (MHD-LLE). The new apparatus consists of two series-wound separation columns for separating essential oil, one is the conventional oil-water separation column, and the other is the extraction column of components from hydrosol using an organic solvent. Therefore, the apparatus can simultaneously collect the essential oil separated on the top of hydrosol and the components extracted from hydrosol using an organic solvent. Based on the yield of essential oil in the first and second separation columns, the effects of parameters were investigated by single factor experiments and Box–Behnken design. Under the optimum conditions (2 mL ethyl ether as the extraction solvent in the second separation column, 12 mL/g liquid-solid ratio, 4.0 min homogenate time, 35 min microwave irradiation time and 540 W microwave irradiation power), satisfactory yields for the essential oil in the first separation column (10.31 ± 0.33 g/kg) and second separation column (0.82 ± 0.03 g/kg) were obtained. Compared with traditional methods, the developed method gave a higher yield of essential oil in a shorter time. In addition, GC–MS analysis of the essential oil indicated significant differences of the relative contents of individual volatile components in the essential oils obtained in the two separation columns. Therefore, the MHD-LLE technique developed here is a good alternative for the isolation of essential oil from A. fruticosa fruit as well as other herbs.
研究领域:
植物化学
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提取技术
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分析化学
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产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2022
·
IF 6.449
Peixi Zhu,Mengya Hao,Feng Su,Wenhao Xu,Qihong Zhang,Weike Su,Erwin Adams
Mechanochemistry is a process that could convert mechanical energy into the substance's internal energy to induce changes. In the current study, mechanochemistry was employed for the first time to extract the essential oil from Citrus aurantium L . var. amara Engl . Materials and reagents were ground at high speed in a planetary ball mill and exposed to solvent extraction. To achieve the best extraction from Citrus aurantium L . var. amara Engl . , the following parameters were selected: 5% fumed silica A200 as solid reagent, ball milling at 300 r/min for 10 min and extraction with n-hexane (1 g/5 mL) during 30 min. These settings gave an essential oil yield of 6.60 ± 0.20%. This is 26 times higher than by hydrodistillation (0.25 ± 0.03%) and more than 3 times higher compared to reflux extraction (2.08 ± 0.16%). The extracts obtained by the three approaches were analysed applying GC-MS. A total of 65 components was identified, including 60 by mechanochemical-assisted extraction, 27 by hydrodistillation and 49 by reflux extraction. Furthermore, scanning electron microscopy was used to observe the changes in material surface structure by the effect of mechanochemical-assisted extraction.
研究领域:
植物学
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化学工程
·
药用植物研究
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yi Hao,Yuan Gao,Luyao Gao,Yulian He,Yingying Niu,Sameer Hussain,Ruixia Gao,Lisa D. Pfefferle,M. Shahid,Sicen Wang
A new class of amphiphilic magnetic adsorbents (denoted as Fe 3 O 4 -GPS-A) is fabricated by functionalization of the Fe 3 O 4 surface with six different amphiphilic silanizing agents that are specifically tailor-made to the chemical structure of PAEs. The resulting Fe 3 O 4 -GPS-A exhibit different contact angles due to the significant changes in functional groups, as revealed by 1 H NMR and FTIR spectroscopy. Among six Fe 3 O 4 -GPS-A, Fe 3 O 4 -DOA and Fe 3 O 4 -OAN exhibit a fast adsorption process (within 60 min) and high adsorption capacity for dibutyl phthalate (DBP) and dioctyl phthalate (DOP), two commonly used phthalate esters (173.7 mg g −1 for DOP and 104.4 mg g −1 for DBP), in conjunction with fast magnetic responsiveness and good thermal stability. The adsorption performance of Fe 3 O 4 -DOA and Fe 3 O 4 -OAN were well-maintained even after ten cycles. Besides, the adsorption mechanism was investigated through adsorption fitting models and theoretical calculations, which inferred that the interactions between adsorbent and adsorbate are mainly based on hydrophobic interactions along with secondary non-covalent contacts. Finally, the adsorbents combined with GC–MS analyses were applied to monitor DBP and DOP in the lake water samples. This work not only opens up a strategy for amphiphilic modification of magnetic adsorbents, but also provides a new avenue in their application for phthalate esters detection.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Zhijie Liu,Yiqun Huang,Shanshan Kong,Junjian Miao,Keqiang Lai
This study was to screen and quantify characteristic volatiles tied to the quality deterioration of reheated pork via simultaneously reheating (75 °C, 30 min) and collecting headspace volatiles of precooked pork (100 °C, 10 min; stored: 0 °C, 0–14 d) for GC–MS analysis. The concentrations of hexanal (6.05 ± 0.86–12.05 ± 0.44 mg/kg), ( E )-2-octenal (1.54 ± 0.16–3.07 ± 0.08 mg/kg), ( E,E )-2,4-heptadienal (1.52 ± 0.44–2.58 ± 0.31 mg/kg) and 8 other selected volatiles in reheated pork increased as the storage time of the precooked counterparts increased. The increase rate of hexanal was 2.9–199 times faster than that of other volatiles based on zero-order reaction fitting ( R 2 = 0.876–0.997). Results from clustering analysis of these volatiles were consistent with their formation pathways tied to lipid autooxidation . This simple approach, reheating and collecting volatiles of precooked meat concurrently, introduces a new possibility for standardizing volatile analysis of precooked meats required being reheated before consumption.
研究领域:
食品科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Xiao Zhang,Bin Ren,Yanhua Xu,Xi Li,Peng Yu,Yongjun Sun,Huaili Zheng
Mn/MCM-41 and imp-Mn/MCM-41 catalysts were prepared in this study through metal heteroatom substitution and impregnation methods, respectively, and their catalytic oxidation performance of toluene under non-thermal plasma (NTP) in a dielectric barrier discharge reactor was studied. The stability of the catalyst and the parameters of catalytic oxidation conditions (initial concentration of toluene, O 2 ratio, and relative humidity of carrier gas) were optimized. Characterization proved that the impregnation method resulted in the existence of manganese in the form of oxides (MnO 2 , Mn 2 O 3 ) outside the pores of MCM-41. Meanwhile, the metal heteroatom substitution method implanted manganese into the mesoporous structure and replaced part of it with Si-O-Mn. NTP catalytic oxidation of toluene, ozone emission, and GC–MS by-product analysis confirmed that 60Mn/MCM-41 catalyst has high catalytic activity. Moreover, the catalyst affected the production of by-products. The stability test revealed that the 60Mn/MCM-41 catalyst still respectively reached 84.6% and 61% in the conversion of toluene and the selectivity of CO 2 under the SED of 558 J/L after 40 h discharge reaction.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2024
·Vol. 149
·期 10
·4491-4503
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IF 3
Chen Yongjia,Zhao Yilin,Hua Min,Pan Xuhai,Jiang Huichun,Jiang Juncheng
We investigated the inhibition of thermal runaway of styrene polymerization by DNPB. DNBP is an inhibitor in styrene polymerization reaction. Polymerization is one of eighteen hazardous processes. Styrene polymerization reaction is characterized by high heat production and fast reaction rate. Firstly, differential scanning calorimetry (DSC) and adiabatic calorimetry (ARC) were chosen to study the effect of different mass of DNBP on thermal behavior in non-isothermal and adiabatic environments. Secondly, exploring the inhibitory effect of DNBP at different runaway temperatures using an oil bath reactor. The results showed that when DNBP was at 0.80%, effective inhibition was obtained at different runaway temperatures. Finally, GC/MS and Gauss16 were used to infer the mechanism of inhibition in terms of macroscopic products and microscopic instabilities. The results showed that the products of the oil bath reactor experiments were related to the mass of DNBP, and when DNBP was 0.80%, the products increased and the main reaction was inhibited. Finally, it was deduced that the nitro group undergoes a possible path of direct addition reaction with the styrene radical before bond breaking.
研究领域:
化学工程
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材料科学
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安全工程
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产品关联
DOI
高影响因子
Scientific Reports
·
2024
·Vol. 14
·期 1
·1-16
·
IF 3.8
Vijh Deepanshi,Gupta Promila
Diabetes is a metabolic condition defined by abnormal blood sugar levels. Targeting starch-hydrolyzing enzymes and Dipeptidyl Peptidase 4 (DPP-4) expressed on the surface of numerous cells is one of the key strategies to lower the risk of Type-2 diabetes mellitus (T2DM). Dalbergia sissoo Roxb. bark (DSB) extracts have been reported to have anti-diabetic properties. This study intended to scientifically validate use of alcoholic and hydro-alcoholic extracts of DSB for T2DM by conducting preliminary phytochemical investigations, characterising potential phytochemicals using Fourier transform infrared (FT-IR) spectroscopy and Gas chromatography-mass spectrometry (GC–MS) analysis followed by comprehensive in-silico analysis. A qualitative phytochemical evaluation indicated the presence of alkaloids, phenolics, glycosides, conjugated acids and flavonoids. Ethanolic extracts showed highest total phenolic content (TPC) (127.072 ± 14.08031 μg GAE/g dry extract) and total flavonoid content (106.911 ± 5.84516 μg QE /g dry extract). Further FT-IR spectroscopy also revealed typical band values associated with phenol, alcohol, alkene, alkane and conjugated acid functional groups. The GC–MS analysis identified 139 compounds, 18 of which had anti-diabetic potential. In-silico ADMET analysis of potential compounds revealed 15 compounds that followed Lipinski’s rule and demonstrated drug-like properties, as well as good oral bioavailability. Molecular docking was utilised to analyse their potential to interact with three targets: α-amylase, α-glucosidase, and DPP-4, which are crucial in managing diabetes-related problems. Molecular Docking analysis and membrane permeability test utilising the PerMM platform revealed that compounds in the extracts, such as Soyasapogenol B and Corydine, had better interactions and permeability across the plasma membrane than standard drugs in use. Molecular dynamics simulations also showed that selected compounds remained stable upon interaction with α-amylase. Overall, using the in-silico approaches it was predicted that DSB extracts contain potential phytochemicals with diverse anti-diabetic properties. It further needs to be investigated for possible development as formulation or drug of choice for treating T2DM.
研究领域:
植物化学
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药物开发
·
计算生物学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2025
·
IF 6.2
Chenyu Yang,Xinru Ma,Yaohui Fan,Feiyu Zou,Wenjuan Bai,Dianming Chu,Haoxi Ben,Zhaoying Li,Yan He
The urgent need to address global energy shortages and environmental pollution has accelerated the development of renewable algal bio-oils. Spirulina stands out as an ideal feedstock for hydrothermal liquefaction (HTL) owing to its high carbon sequestration rate, non-competition with arable land, and rich protein-lipid content. However, Spirulina-derived bio-oil typically suffers from high oxygen content and low heating value. To overcome these limitations, this study developed a microwave-assisted two-stage HTL process integrated with a Ni-loaded, alkali-modified HZSM-5 catalyst. Unlike conventional catalysts that often rely on costly noble metals or suffer from diffusion limitations in microporous structures, this system employs earth-abundant nickel on a hierarchically structured zeolite to enhance both cost-effectiveness and catalytic efficiency. HZSM-5 was treated with NaOH to create mesoporosity, followed by Ni impregnation to introduce hydrogenation functionality. The effects of NaOH concentration and Ni loading on catalyst properties were systematically investigated. Process optimization was performed via response surface methodology using a 3 % sulfuric acid medium, and bio-oil composition was analyzed by GC/MS. Modification with 1 mol/L NaOH increased hydrocarbon content to 32.9 %, while subsequent loading with 5 wt% Ni synergistically boosted the yield to 48.1 %. Molecular dynamics simulations provided mechanistic insights into bond cleavage and conversion pathways of Spirulina-derived model compounds in subcritical water. Compared with existing catalytic systems, this study significantly improves the quality of biofuels, providing an efficient catalytic strategy and fundamental insights for the production of high-quality bio-oil from spirulina.
研究领域:
可再生能源
·
催化
·
生物燃料生产
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化学工程
·
环境科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）