JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2024
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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
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能源化学
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产品关联
DOI
高影响因子
CELLULOSE
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2021
·Vol. 28
·期 8
·5123-5134
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IF 5.044
Shen Yanqin,Yao Yijun,Wang Zhongliang,Wu Hailiang
A series of hydroxypropylated starch (HPS) that can be dissolved in water at 60–65 °C was obtained via two-step method in water system from corn starch. The structure and property of the HPS and its gelatinization temperature were characterized by Fourier transform infrared spectrometer, nuclear magnetic resonance spectroscopy ( 1 H NMR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and transmission electron microscope (TEM). It was concluded that hydroxypropyl mainly bonded on the hydroxyl group at C 2 position from glucose residue of starch in the form of C–O–C, and the substitution level at C 6 position was slightly higher than that at C 3 position, as well as the crystallinity of starch decreased from 52.41% to 29.4% due to the introduction of hydroxypropyl and was confirmed by XRD. At the same time, the grooves on the surface of starch granules were observed by SEM. The above-mentioned two synergies promoted the permeation and transmission of water molecules in the starch microstructure. Moreover, the gelatinization temperatures and enthalpy of synthetic HPS were lower than those of raw corn starch, as further confirmed by DSC. This caused the HPS with a molar substitution greater than 0.1 to be soluble in water at 65 °C, and its dissolution state was similar to that of HPS at 95 °C (transmittance above 55%), as well as exhibited high slurry stability. Interestingly, compared with the raw starch, the HPS film showed excellent tensile strength and elongation at the relative humidity of 65%, which could be attributed to the hydrophilic ether bond and the flexible alkyl chain bonded on the structure of starch. This study will provide a new way for the preparation of high performance starch size for sizing yarn at medium–low temperature. Graphic abstract
研究领域:
食品科学
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材料科学
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纺织工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2022
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IF 8.025
Piengtawan Tappiban,Jiajia Zhao,Yu Zhang,Yan Gao,Lin Zhang,Jinsong Bao
In this study, electron beam irradiation (EBI; 2, 4, 6, 8 and 10 kGy), hydroxypropylation (HP) and dual modification of EBI-HP were applied to modify corn and potato starches. The results showed that the molar substitution (MS) of EBI-HP modified corn and potato starches were in the range of 0.060–0.087 and 0.080–0.124, respectively. After modifications, amylose content of corn (30.0 %) and potato (31.2 %) starches were declined to 24.2–28.1 % and 26.1–29.5 %, respectively, and relative crystallinity was reduced from 35.5 to 30.0 % for corn and 34.1 to 20.2 % for potato. Pasting properties decreased significantly in both starch sources with increasing irradiation dose. EBI decreased springiness, enthalpy of retrograded starch (ΔHr) and percentage of retrogradation (R%) on corn starches, which were different from those effects observed on potato starches. Meanwhile, HP increased peak viscosity up to 312.6 RVU and 1359.3 RVU for corn and potato starches, respectively. Moreover, EBI-HP was highly responsible for the decreases in the textural, gelatinization and retrogradation properties and relative crystallinity in both corn and potato starches. These results enhance the understanding of starch functionality modified by using both physical and chemical methods, and provide further insights on food and non-food applications.
研究领域:
食品科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2014
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IF 3.096
Zhen-Hua Cheng,Jun Huang,Sheng Hu,Cheng-Jun Jiang,Qing Ge,Hong-Wu Lai,Jin-Yan Gong,Pei-Long Sun,Jian-Wei Mao,Le-He Mei
Chitosan was prepared by alkaline N -deacetylation of β-chitin and hydroxypropyl derivatives with different degrees of substitution (DS) were synthesized. It was characterized by Fourier transform infrared (FT-IR) and elemental analysis. The DS of hydroxypropyl chitosan (HPCS) calculated by an element analyzer were 0.42, 0.75, 1.20, 1.82 and 2.25. HPCS showed better foam capacity and stability than that of chitosan, and the effectiveness correlated well with the DS of HPCS. The highest bile acid-binding capacity of all five HPCS reached 56.02 mg/g, which was 4.0-fold higher than that of chitosan. The scavenging ability of HPCS against hydroxyl and ABTS radicals improved with increasing concentration. The correlation between the hydroxypropyl content (DS) of HPCS and scavenging ABTS radical ability was positive. The hydroxyl radicals scavenging activity of HPCS correlated well with its increasing concentration, and EC 50 values were below 12.5 mg/mL. These results indicated that hydroxypropylation is a possible approach to obtain chitosan derivatives with desirable physiochemical properties.
研究领域:
生物化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
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2025
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IF 6.6
Chunmei Shi,Jiangong Ma,Xinyue Zhang,Yawen Zhang,Lihong Fu,Xiaowen Wang
Foxtail millet is a specialty grain mainly containing starch. In this research, the physicochemical properties of foxtail millet starch were modified using combined ultrasonic (0, 100 W, 200 W, 300 W, 400 W and 500 W) and hydroxypropylation with 20% propylene oxide (based on starch weight) to evaluate the effects of these modifications. The native foxtail millet starch granules exhibited a glabrous surface and were polygonal or spherical. The hydroxypropylation treatment slightly degraded the surface of the native foxtail millet starch granule, while ultrasonic-hydroxypropylation treatment resulted in depressions and cracks of the surfaces of the native foxtail millet starch granule. X-ray diffraction pattern showed that the foxtail millet starch was of crystal type "A". Notably, ultrasonic-hydroxypropylation and hydroxypropylation treatments did not affect the crystal shape of foxtail millet starch but decreased the relative crystallinity. Furthermore, ultrasonic-hydroxypropylation treatment blurred the polarized cross structure of foxtail millet starch and increased the content of amylose. Ultrasonic-hydroxypropylation treatment also resulted in a wider range of granule size distribution and increased the average granule size of foxtail millet starch. Hydroxypropylation and ultrasonic-hydroxypropylation treatments increased the transparency, peak viscosity, and swelling power of foxtail millet starch. Additionally, the treatments decreased retrogradation and pasting temperature of foxtail millet starch. Compared with single hydroxypropylation modification, ultrasonic-hydroxypropylation complex modification significantly improved the physicochemical properties of foxtail millet starch. Notably, ultrasonic power impacted the physicochemical properties of ultrasonic-hydroxypropylated foxtail millet starch. Specifically, the millet starch (UH-200) treated with 200W ultrasonic combined with hydroxypropylation exhibited the best physicochemical properties, with a significantly higher transmittance (24.62%) and lower retrogradation (14.47%) compared to the other groups. These findings indicate that ultrasonic combined with hydroxypropylation can modify the physicochemical properties of foxtail millet starch , thus improving its industrial utilization.
研究领域:
食品科学
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淀粉化学
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谷物化学
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食品加工
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材料科学
✓ 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）