JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2016
·
IF 3.652
Shiliang Wu,Dekui Shen,Jun Hu,Huiyan Zhang,Rui Xiao
The pyrolytic characteristics of cellulose, cellobiose and glucose were examined by TG-FTIR combined with Py-GC–MS, in order to gain the effect of β -O-4 glycosidic bond on the pyrolysis process. In TG-FTIR analysis, two mass loss peaks were observed for cellobiose and glucose, indicating dehydration in low temperature stage and consequently intensive cracking of glycosidic bond and fragments for cellobiose. The samples were tested in Py-GC–MS at the temperature of 300, 500 and 900 °C according to their mass loss characteristics from TG-FTIR. Formation of furans from cellobiose, which involved the cracking of β -O-4 glycosidic bond, was prominent over other products, compared to that of cellulose and glucose. Four possible chemical pathways for the cleavage of β -O-4 glycosidic bond have been proposed with regard to the formation of furans and anhydrosugars from cellulose. Besides, another two reaction pathways leading to the formation of levoglucosan were also suggested.
研究领域:
生物质化学
·
热化学转化
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2025
·
IF 6.2
Tianxiang Zhu,Songlin Liu,Yu Gao,Xiongjie Sun,Haiming Hu,Zhigang Zhang,Wenwen Zhang,Lei Xiong,Hongtao Liu
Endoglucanases may not only act on β-1,4-linkages in β-glucan but also target d-glucose in glucomannan, which can expand their utility in the preparation of prebiotics. In this study, a highly efficient endoglucanase (BlGH5) from Bacillus licheniformis BJ2022 was expressed and characterized. BlGH5 exhibited the highest activity at pH 7.0 and 60 °C. It maintained over 80% activity at pH 4.0–7.0 and 30–60 °C. BlGH5 specifically cleaved β-1,4-glycosidic bonds linked to d-glucose. Site-directed mutagenesis results suggested that Arg91, Asn167, Glu168, Trp206, His228, Tyr230, Ser263, and Trp290 are key residues for its binding and catalytic activity. Moreover, BlGH5 displayed high activity against konjac glucomannan (KGM), indicating that BlGH5 could be used to prepare low-molecular-weight konjac glucomannan (KGM-L). Based on the physicochemical properties of KGM and KGM-L, KGM-L was characterized by reduced molecular weight and viscosity. Fecal fermentation experiments demonstrated that KGM and KGM-L could promote the production of short-chain fatty acids (SCFAs). Still, KGM-L was more conducive to the growth of the gut probiotics. In conclusion, we identified an endoglucanase for the degradation of KGM. Results indicated that KGM-L would have superior prebiotic effects. Thus, our study provides a basis for the future development and application of KGM-L as a prebiotic.
研究领域:
酶学
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食品科学
·
微生物学
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产品关联
DOI
PubMed
高影响因子
ACS Catalysis
·
2021
·
IF 13.084
Yiwen Yang,Haifeng Qi,Huixiang Li,Zhanwei Xu,Xiumei Liu,Shuyin Yu,Zongchao Conrad Zhang
Efficient hydrolysis of β-1,4-glycosidic bonds of cellulose is a pivotal step in biorefineries of cellulosic biomass. In this work, we discovered that paired PdCl2–CuCl exhibited excellent synergetic catalytic activity over the single PdCl2 or CuCl in the hydrolysis of β-1,4-glycosidic bonds in 1-butyl-3-methylimidazolium chloride ([BMim]Cl) and further investigated the catalytic species in this system. The catalytic activity increased and reached a plateau at a CuCl/PdCl2 ratio of 1 with increasing molar ratio of CuCl/PdCl2 while keeping the Pd concentration constant. A combination of experimental evidence based on in situ far-infrared absorption, X-ray absorption, X-ray photoelectron, and electron paramagnetic resonance spectroscopies and DFT calculations demonstrate the coupling reaction between [PdIICl4]2– and [CuICl3]2– via the Cl bridge to form the heterometallic complex anion [Cl2PdII–Cl–CuICl2]2–. The heterometallic species is stable during the reaction and maintains its catalytic performance in the presence of various oxygenate additives. Using paired PdCl2–CuCl as a catalyst, the activation energy of hydrolytic cleavage of β-1,4-glycosidic bonds of cellobiose is determined as low as 95.8 kJ/mol. PdCl2–CuCl/[BMim]Cl combined with CrCl3 can be reused five times in cellobiose conversion to 5-hydroxymethylfurfural (5-HMF) without an apparent decrease of catalytic activity. The performance of this catalytic system is further verified for efficient cellulose conversion. More than 60% product yield is obtained at 100 °C from the cellulose, affording monosaccharides for efficient production of high value-added chemicals, such as 5-HMF, when CrCl3 is present to catalyze the conversion of glucose to 5-HMF.
研究领域:
生物化学
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催化化学
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生物质能
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Yu Zhang,Niuniu Wu,Jingyi Wang,Zehong Chen,Zhijing Wu,Mengzi Song,Ziming Zheng,Kaiping Wang
Grifola frondosa polysaccharide (GFP) is mainly composed of α-1,4 glycosidic bonds and possesses multiple pharmacological activities. However, the absence of pharmacokinetic studies has limited its further development and utilization. Herein, GFP was labeled with 5-DTAF (FGFP) and cyanine 5.5 amine (GFP-Cy5.5) to investigate its gastrointestinal metabolism characteristics and mechanism. Significant distributions of the polysaccharide in the liver and kidneys were observed by near infrared imaging. To investigate the specific distribution form of the polysaccharide, in vitro digestion models were constructed and revealed that FGFP was degraded in saliva and rat small intestine extract. The metabolites were detected in the stomach and small intestine, followed by further degradation in the distal intestine in the in vivo experiment. Subsequent investigations showed that α-amylase was involved in the gastrointestinal degradation of GFP, and its metabolite finally entered the kidneys, where it was excreted directly with urine.
研究领域:
食品科学
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生物化学
·
药理学
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产品关联
DOI
PubMed
高影响因子
AUSTRALIAN JOURNAL OF CHEMISTRY
·
2018
·Vol. 71
·期 8
·559-565
·
IF 1.059
Ren-Qiang Yang,Ni Zhang,Xiang-Guang Meng,Xiao-Hong Liao,Lu Li,Hong-Jin Song,Ren-Qiang Yang,Ni Zhang,Xiang-Guang Meng,Xiao-Hong Liao,Lu Li,Hong-Jin Song
A novel difunctional magnetic nanocatalyst (DMNC) was prepared and used to catalyse the hydrolytic breakage of β-1,4-glycosidic bonds. The functional nanoparticle displayed excellent catalytic activity for hydrolysis of cellobiose to glucose under moderate conditions. The conversion of cellobiose and yield of glucose could reach 95.3 and 91.1 %, respectively, for a reaction time of 6 h at pH 4.0 and 130°C. DMNC was also an efficient catalyst for the hydrolysis of cellulose: 53.9 % microcrystalline cellulose was hydrolyzed, and 45.7 % reducing sugar was obtained at pH 4.0 and 130°C after 10 h. The magnetic catalyst could be recycled and reused five times without significant loss of catalytic activity.
研究领域:
生物化学
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催化化学
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产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2022
·Vol. 12
·期 6
·1968-1977
·
IF 6.177
Yiwen Yang,Haifeng Qi,Zhanwei Xu,Z. Conrad Zhang
In this work, we identified the prevailing catalytically active species evolved from paired PdCl2–CuCl2 in 1-butyl-3-methylimidazolium chloride ([BMim]Cl) that displayed dramatic synergy between the two metal chlorides in catalyzing the hydrolysis of β-1,4-glycosidic bonds in cellulose. Ultraviolet-visible (UV-vis), far infrared (FIR), and electron paramagnetic resonance (EPR) spectroscopy provide clear evidence for the prominent evolutionary pathways to form the catalytically active species. It is observed that the strong synergy between [PdIICl4]2− and [CuIICl4]2− is initiated by the presence of a saccharide. In the absence of a saccharide, the spectroscopic features of [PdIICl4]2− and [CuIICl4]2− in their paired solution show little change with respect to those of individual metal chloride solutions. The evolution of a highly active heterometallic PdII–Cl–CuI complex from paired PdCl2–CuCl2 in the presence of saccharides is revealed by the transition of the FIR absorption peak of PdII–Cl. Glycolaldehyde as the simplest model compound, which is the same as the reducing end group of saccharides, is applied to determine the possible catalytic species. X-ray absorption spectroscopy (XAS) verifies that [CuIICl4]2− is reduced to [CuICl3]2− by glycolaldehyde. The HCl generated from reduced [CuIICl4]2− is also found to contribute to the hydrolysis of cellobiose, serving as another catalytically active species in paired PdCl2–CuCl2/[BMim]Cl. Paired PdCl2–CuCl2 pretreated with glycolaldehyde exhibits dramatically higher activity than direct use of paired PdCl2–CuCl2 in cellobiose conversion. Strikingly, the PdII–Cl–CuI complex is found to be substantially more active than HCl in the hydrolysis of β-1,4-glycosidic bonds as evidenced by the sustained high cellobiose conversion after neutralization of HCl with NaOH.
研究领域:
催化
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化学工程
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材料科学
·
分析化学
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产品关联
DOI
高影响因子
CELLULOSE
·
2015
·Vol. 22
·期 1
·329-338
·
IF 3.573
Yu Yeli,Zhang Yong,Yang Xiaogang,Liu Hongyi,Shao Lan,Zhang Xiumei,Yao Juming
A cellulose-based superabsorbent exhibits excellent water absorbency and retention performance as well as biodegradability. However, the detailed biodegradation process in soil has not been monitored yet. Yellowing is another important factor affecting its appearance and storage. In this work, cellulose from flax yarn wastes (FYW) was used as the skeleton material to synthesize a cellulose-g-P(AA-co-AM) (FYW/PAA) superabsorbent. The properties of the FYW/PAA superabsorbent were characterized, especially its biodegradation process and yellowing mechanism. The resultant FYW/PAA presented excellent water absorbency and retention capabilities of 886 g/g in deionized water and 73.2 wt% after being dried at 60 °C for 12 h, respectively. The fracturing of β-1,4-glycosidic bonds on the flax-cellulose macromolecules is the main reason for the biodegradation of FYW/PAA in soil. This causes a 70.8 wt% degradation after FYW/PAA has been buried in soil for only 60 days. The drying method and UV irradiation have important implications for the yellowing of FYW/PAA. They facilitate the generation of chromophore and auxochrome groups on the flax-cellulose macromolecules. 2,6-Di-tert-butyl-4-methylphenol (BHT) exhibits excellent antioxidant properties to inhibit the yellowing of FYW/PAA products.
研究领域:
环境科学
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材料科学
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化学工程
·
高分子科学
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2025
·
IF 6.2
Yuejie Qiu,Longbin Li,Leping Zhang,Jianxin Jiang,Liwei Zhu
This study develops a catalytic system using pyruvic acid (PYA) and Fe2+ to efficiently coproduce xylo-oligosaccharides (XOS) and (manno-oligosaccharides) MOS from food material (Gleditsia sinensis Lam. fruit.) and its waste peel, respectively. The system achieved maximum yields of 67.12% XOS and 57.32% MOS without toxic byproducts such as furfural and 5-hydroxymethylfurfural (5-HMF) below 130 °C. The process employs a two-stage mechanism, where PYA cleaves galactose side chains and xylan backbones, while Fe2+ stabilizes β-1,4-glycosidic bonds, resulting in polymerization degree ratios of X2–3/X4–5 at 0.975 and M2–3/M4–5 at 0.96. The composite oligosaccharides, PFMX, showed significant prebiotic effects, enhancing Bifidobacterium adolescentis growth to 3.4 × 108 CFU/mL─144% higher than commercial fructooligosaccharides (FOS). The concentration of short-chain fatty acids (SCFAs) was 15.09 g/L, with specific products propionic acid (1.44 g/L) and butyric acid (0.15 g/L). PFMX effectively regulates substrate utilization and SCFA metabolism, offering a promising strategy for developing functional foods that target gut inflammation.
研究领域:
催化化学
·
碳水化合物化学
·
食品科学与技术
·
益生元与肠道微生物
·
绿色化学
·
生物炼制
✓ 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）