Sustainable Energy & Fuels
·
2018
·Vol. 2
·期 7
·1530-1541
·
IF 0
Xincheng Wang,Yongji Song,Chongpin Huang,Bin Wang
Lactic acid (LA) is a versatile platform chemical for the production of biodegradable polymers as well as starting materials for the pharmaceutical industry. In this study, crystalline niobium phosphates directed by various surfactants were prepared by a facile sol–gel method and studied as heterogeneous Lewis acid catalysts for the direct conversion of triose sugars to LA under aqueous conditions. Metal oxides were used to alter the surface acidity, and pyridine FTIR analyses demonstrated the presence of both Lewis and Brønsted acid sites, which played essential roles in the conversion of biomass sugars. The incorporation of SnO2 and the use of surfactants significantly lowered the Brønsted-to-Lewis site ratio. P–OH groups were determined to be the origin of the Brønsted acid sites, while the partially hydrolyzed framework of tin and niobium species led to the formation of Lewis acid sites. The cationic surfactant-modified samples with highly crystalline structures outperformed the amphiphilic surfactant-modified samples. The optimum cetyltrimethylammonium bromide-modified catalyst afforded an LA yield of ca. 92% with the complete dihydroxyacetone (DHA) conversion at 160 °C. Furthermore, the isomerization of pyruvaldehyde (PA) was found to be the rate-determining step, while the rehydration of PA to DHA could occur in the current reaction system. A possible reaction mechanism involving the evolution of two key catalytic intermediates was proposed. In addition, crystalline niobium phosphates were also effective in the aqueous dehydration of sugars to furan derivatives with a 44% 5-hydroxymethylfurfural yield from glucose after 1 h. The current study can hopefully serve as a model for the development of novel solid acid catalysts for the conversion of sugars to platform chemicals.
研究领域:
化学工程
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催化科学
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生物质转化
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DOI
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Baojun Feng,Hong Liao,Wenjun Ying,Junhua Zhang,Zhangjing Chen
Short-chain xylo-oligosaccharides (XOS) such as xylobiose (X2) and xylotriose (X3) have higher biological activities. Therefore, it is interesting to produce highly active XOS enriched with X2 and X3. In this work, pH-controlled lactic acid (LA) hydrolysis was used to produce XOS from xylan in moso bamboo and xylanase was used to convert high DP XOS into low DP XOS to increase the percentage of X2 + X3 in XOS. A 33.1 % XOS yield was obtained from 2 % LA hydrolysis (pH = 3.2). After xylanase hydrolysis of the LA hydrolysate, the total XOS yield reached 64.1 %, with X2 + X3 yield reaching 58.4 %. The percentage of X2 + X3 increased from 52.3 % to a high level of 91.0 %. The deep eutectic solvent pretreatment removed 87.2 % lignin from the residue and the glucose yield of the delignified residue hydrolyzed by cellulase was 96.9 %. The results suggested that the integrated process of LA and xylanase hydrolysis could effectively produce X2 + X3 from xylan in moso bamboo.
研究领域:
生物化学
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可再生资源与环境科学
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DOI
PubMed
高影响因子
MOLECULES
·
2020
·Vol. 25
·期 21
·5140
·
IF 3.267
Zhou-Tao Fang,Yi-Qing Lv,Chu-Jun Song,Jing Jin,Jian-Liang Lu,Hai-Rong Xu,Jian-Hui Ye
Flavonol glycosides are important components of tea leaves, contributing to the bioactivities as well as bitterness and astringency of tea. However, the standards of many flavonol triglycosides are still not available, which restricts both sensory and bioactivity studies on flavonol glycosides. In the present study, we established a simultaneous preparation method of seven flavonol triglycoside individuals from tea leaves, which consisted of two steps: polyamide column enrichment and preparative HPLC isolation. The structures of seven flavonol triglycoside isolates were identified by mass and UV absorption spectra, four of which were further characterized by nuclear magnetic resonance spectra, namely, quercetin-3-O-glucosyl-rhamnosyl-glucoside, quercetin-3-O-rhamnosyl-rhamnosyl-glucoside, kaempferol-3-O-glucosyl-rhamnosyl-glucoside and kaempferol-O-rhamnosyl-rhamnosyl-glucoside. The purities of all isolated flavonol triglycosides were above 95% based on HPLC, and the production yield of total flavonol glycosides from dry tea was 0.487%. Our study provides a preparation method of flavonol triglycosides from tea leaves, with relatively low cost of time and solvent but high production yield.Keywords:Camellia sinensis;flavonol glycosides;tri-glycosides;preparative HPLC;isolation;NMR measurement
研究领域:
植物化学
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食品科学
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分析化学
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DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2015
·Vol. 5
·期 9
·4410-4421
·
IF 5.426
Xincheng Wang,Fengbing Liang,Chongpin Huang,Yingxia Li,Biaohua Chen
Lactic acid (LA) is an important intermediate in the fine chemical industry because it is utilized as a building block for the production of biodegradable plastics. In this study, a series of tin phosphate phase transfer catalysts modified with several surfactants have been prepared by a facile one-pot synthesis method and tested for the direct conversion of trioses to LA under hydrothermal conditions. Poly(ethylene glycol) (PEG) was identified as the most promising surfactant, and the product distribution closely depended on the reaction temperature, catalyst loading and substrate concentration. Complete DHA conversion and a good yield of up to 96.1% of LA were obtained at 140 °C after 4 h of reaction time. Pyridine FTIR demonstrated the presence of Brønsted and Lewis acid sites, which play crucial roles in the dehydration of DHA to pyruvaldehyde (PA) and the following isomerization of generated PA to LA. Furthermore, the isomerization of PA to LA was found to be the rate-determining step. A possible reaction mechanism was proposed: 1) the coordination between PEG and the metal ions caused a greater separation of the tin ions from the phosphate anions, making them more potent Lewis acid sites, and 2) the PEG behaved as a phase transfer catalyst during the reaction. This study paves the way for the further design of improved solid acid catalysts for aqueous phase production of LA from carbohydrates.
研究领域:
生物化学
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催化化学
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DOI
高影响因子
SYNTHESIS-STUTTGART
·
2021
·Vol. 53
·期 14
·2435-2448
·
IF 3.157
Xin Zhou,Qing Long,Dongwei Li,Jingru Gao,Qikai Sun,Shaozi Sun,Yong Su,Peng Wang,Wenjie Peng,Ming Li
Structurally defined and pure oligosaccharides corresponding to β-glucans have attracted great attention because of their potential properties as immunostimulating agents and as antigens of vaccine candidates. We herein describe a convergent synthesis of ready-to-conjugate tridecasaccharides composed of a β-1,3-glucan nonasaccharide backbone and a β-1,6-glucan tetrasaccharide branch. The assembly was achieved by employing trichloroacetimidate glycosylations and features the gram-scale preparation of the nonasaccharide backbone and installation of the tetrasaccharide branch involving orthoester rearrangement to the glycoside.
研究领域:
有机化学
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生物化学
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疫苗研究
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DOI
高影响因子
INTERNATIONAL JOURNAL OF TOXICOLOGY
·
2023
·
IF 2.2
Xu Fang,Wei Zhu,Huiying Zhao,Wencheng Yin,Xiao Song,Fengxin Liu
Lacto-N-triose II (LNT II), an essential human milk oligosaccharide and precursor to lacto-N-tetraose (LNT) and lacto-N-neotetraose (LNnT), was evaluated for safety. Genotoxicity was assessed through in vitro tests including Bacterial Reverse Mutation Test and mammalian cell micronucleus test, and a subchronic oral gavage toxicity study was conducted on juvenile Sprague-Dawley rats. In this study, LNT II was administered at dose levels of 0, 1,500, 2,500, or 5,000 mg/kg body weight (bw)/day for 90 days, followed by a 4-week treatment-free recovery period. LNT II was non-genotoxic in the in vitro assays. No compound-related effects were observed across all dosage levels based on various measures, including clinical observations, body weight gain, feed consumption, clinical pathology, organ weights, and histopathology. Consequently, the highest dosage of 5,000 mg/kg bw/day was established as the no-observed-adverse-effect-level (NOAEL). These results suggest the safe use of LNT II in young children formula and as a food ingredient, within the limits found naturally in human breast milk.
研究领域:
营养学
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毒理学
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儿科学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Zhuoning Cao,Chengqiang Li,Hong Jiang,Francesco Secundo,Xiangzhao Mao
β- N -acetylhexosaminidases garnered attention in the enzymatic synthesis of lacto- N -triose II (LNT2) as the backbone precursor of human milk oligosaccharides (HMOs). In this study, β- N -acetylglucosaminidases Hex(Sv)-2557 from Streptomyces violascens ATCC 27968 was engineered based on a stabilizing intermediate strategy to improve its transglycosylation activity for LNT2 synthesis. A mutant Hex(Sv)-2557(D297K) with a transglycosylation activity of 38.4 U/mg with p NP-GlcNAc −1.9-fold higher than that of Hex(Sv)-2557– was obtained and characterized. Instead, the hydrolase activity of the mutant was 73 % lower compared to the wild-type enzyme. Importantly, the mutant can use N -acetyl chitobiose (GlcNAc 2 ) as the donor for LNT2 synthesis. The LNT2 yield of 14.85 % was obtained when the synthetic reaction, catalyzed by the mutant Hex(Sv)-2557(D297K), started from whey powder and GlcNAc 2 -prepared from chitin by chitinase ChiA and ChiB. This study has altered the donor for the action by directed modification and promoting the high-value utilization of whey powder and chitin.
研究领域:
生物化学
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酶工程
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食品科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2024
·
IF 5.7
Chengqiang Li,Zhuoning Cao,Hong Jiang,Francesco Secundo,Xiangzhao Mao
β-N-Acetylhexosaminidases have attracted much attention in the enzymatic synthesis of lacto-N-triose II (LNT2) as a backbone precursor of human milk oligosaccharides (HMOs). In this study, a novel glycoside hydrolase (GH) 20 family β-N-acetylhexosaminidase, FlaNag2353, from Flavobacterium algicola was biochemically characterized and applied to synthesize LNT2. FlaNag2353 displayed optimal activity to p-nitrophenyl N-acetyl-β-d-glucosaminide (pNP-GlcNAc) at 40 °C and pH 8.0. In addition to its excellent hydrolysis activity toward pNP-GlcNAc and chitooligosaccharides, FlaNag2353 showed trans-glycosylation activity. Under conditions of pH 9.0 and 55 °C for 2 h and utilizing 200 mM lactose and 10 mM pNP-GlcNAc, FlaNag2353 synthesized LNT2 with a conversion ratio of 4.15% calculated from pNP-GlcNAc. Moreover, when applied to LNT2 synthesis with 10 mM pNP-GlcNAc and 9.7% (w/v) industrial waste whey powder, FlaNag2353 achieved a conversion ratio of 2.39%. This study has significant implications for broadening the applications of GH20 β-N-acetylhexosaminidases and promoting the high-value utilization of whey powder.
研究领域:
生物化学
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酶学
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食品科学
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生物技术
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产品关联
DOI
PubMed
高影响因子
Journal of Ocean University of China
·
2023
·Vol. 22
·期 6
·1683-1691
·
IF 1.6
Yue Jiali,Cheng Wei,Wei Shutong,Liu Guilin,Zhou Meichen,Lv Zhihua,Yu Mingming
A sensitive, rapid, and robust ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was established for the first time to quantify agarotriose (A3) in rat plasma, tissues, urine, and feces. A3 and stachyose (internal standard) were separated by a BEH amide column at 65 °C under the mobile phase of 10 mmol L −1 ammonium acetate-acetonitrile (42:58, v / v ) with 350 µL min −1 . The acquisition of transitions was carried out in multiple reaction monitoring (MRM) pattern operating with positive ionization at m / z 509.16 ≥ 329.15 for A3 and m / z 689.15 ≥ 527.11 for stachyose. The linearity ranges of A3 were 10 to 5000 nmolL −1 for plasma, 20 to 10000 nmolL −1 for tissues, and 40 to 20000 nmolL −1 for urine and feces. The accuracy and precision ranged from 90.9% to 111.6% and 0.7% to 10.1%, respectively. The stability was between 86.1% and 102.5%. The extraction recovery was consistent and reproducible. The matrix effect ranged from 1.5% to 11.4%. The pharmacokinetic, tissue distribution, and excretion studies were successfully conducted with the validated method. Results showed that A3 could be absorbed by rats, and the absolute bioavailability was 6.7%. Furthermore, it was rapidly distributed in rat tissues and mainly eliminated via feces excretion (67.0%) after oral administration. For intravenous bolus, 85.5% was recovered, and renal excretion was the primary pathway (77.6%) for cumulative recovery.
研究领域:
分析化学
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药理学
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代谢组学
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2022
·
IF 5.895
Zhen Li,Qiang Huang,Yu Zheng,Yong Zhang,Xin Li,Shiqing Zhong,Zhijiang Zeng
Identifying the components of Camellia oleifera honey and pollen and conducting corresponding toxicological tests are essential to revealing the mechanism of Camellia oleifera toxicity to honey bees. In this research, we investigated the saccharides and alkaloids in honey, nectar, and pollen from Camellia oleifera, which were compared with honey, nectar, and pollen from Brassica napus, a widely planted flowering plant. The result showed that melibiose, manninotriose, raffinose, stachyose, and lower amounts of santonin and caffeine were found in Camellia oleifera nectar, pollen, and honey but not in B. napus nectar, pollen, and honey. Toxicological experiments indicated that manninotriose, raffinose, and stachyose in Camellia oleifera honey are toxic to bees, while alkaloids in Camellia oleifera pollen are not toxic to honey bees. The toxicity mechanism of oligosaccharides revealed by temporal metabolic profiling is that oligosaccharides cannot be further digested by honey bees and thus get accumulated in honey bees, disturbing the synthesis and metabolism of trehalose, ultimately causing honey bee mortality.
研究领域:
昆虫学
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毒理学
·
植物科学
·
农业科学
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DOI
PubMed
高影响因子
BMC MUSCULOSKELETAL DISORDERS
·
2024
·Vol. 25
·期 1
·1-13
·
IF 2.2
Xu Kuishuai,Zhang Liang,Wang Tianrui,Yu Tengbo,Zhao Xia,Yu Ning,Zhang Yingze
Objective To assess the mechanism of supraspinatus tendinopathy induced by type 2 diabetes mellitus (T2DM) in rats using untargeted metabolomics analysis. Methods The liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics approach was used to screen tendon biomarkers of supraspinatus tendinopathy in rats with T2DM. Seventy-eight Sprague-Dawley rats were divided into normal group (NG) and T2DM groups. Rats in T2DM groups were divided into 12-week (T2DM-12w), and 24-week (T2DM-24w) subgroups according to the time point of the establishment of the T2DM rat model. Histological evaluation (modified Bonar score) and biomechanical testing were used to analyze the adverse effects of type 2 diabetes on the tendon of the supraspinatus muscle in rats.Three comparable groups were set up, including T2DM-12w group vs. NG, T2DM-24w group vs. NG, and T2DM-24w group vs. T2DM-12w group. Differentially expressed metabolites (DEMs) in the supraspinatus tendons in the three groups of rats were analyzed using LC-MS, and data were analyzed using multivariate statistical methods to screen potential biomarkers. The DEMs included in the intersection of the three groups were identified as those associated with the development of diabetic supraspinatus tendinopathy, and trend analysis and pathway topology analysis were performed. Results With the progression of diabetes, the tendinopathy of the supracinatus muscle of diabetic rats gradually intensified, mainly manifested as inflammatory reactions, disordered collagen fibers, fat infiltration, and increased modified Bonar score. The intersection of DEMs among the three comparable groups was resulted in the identification of 10 key DEMs, in which melezitose and raffinose showed a continuous increasing trend with the prolongation of disease course. By pathway topology analysis, 10 DEMs ( P < 0.01) were mainly associated with the pathways of galactose metabolism, which could be involved in the development of diabetes-induced supraspinatus tendinopathy. Conclusion T2DM causes tendinopathy of the supraspinatus muscle in rats. 10 key DEMs obtained by untargeted metabolomics assay suggested that the development of diabetes-induced supraspinatus tendinopathy was associated with changes in metabolic pathways, such as galactose metabolism. melezitose and raffinose hold promise as a biomarker for disease discrimination and/or disease indication in diabetic supraspinatus tendinopathy.
研究领域:
代谢组学
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糖尿病研究
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肌肉骨骼疾病
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动物模型
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DOI
PubMed
高影响因子
CHROMATOGRAPHIA
·
2022
·Vol. 85
·期 5
·395-403
·
IF 2.213
Tang Zekun,Ye Fanfan,Wan Huihui,Song Yuming,Fan Weiwei,Chi Zhanyou,Du Qinqin,Cai Rui,Xu Qiang,Zhang Hua
Liquid chromatography–mass spectrometry (LC–MS) technique has been widely used for the determination of trace carbohydrate compounds in biological samples. However, the ionization efficiency of carbohydrates under the conditions of common electrospray ion sources is poor, and thus chemical derivatization treatment is usually needed. Here, a pre-column derivatization based on dibenzylamine method coupling with LC–MS/MS was developed for the analysis of glucose, xylose, ribose, galactose, maltose, and maltotriose. Aldosaccharide compounds were labeled by dibenzylamine within 3 h at 75 °C. The derivatized aldosaccharides were separated on a polar-copolymerized C18 column and identified with electrospray ionization mass spectrometer in positive mode. The dibenzylamine-derived product of 3-O-methyl-D-glucopyranose was used as the internal standard for the quantitation of derivatized aldosaccharide products. Under the optimized condition, good correlation coefficients ( R 2 > 0.9903) for all carbohydrates were obtained. Outstanding sensitivity with limits of quantitation (S/N 10) of 0.35–20 ng mL −1 and limits of detection (S/N 3) of 0.1–7 ng mL −1 were achieved. The developed method was successfully utilized for the determination of aldosaccharides in sample of corn stalk fermentation. The recoveries of the method were in the range of 92.59–103.22% with relative standard deviations of 1.08–6.08%.
研究领域:
分析化学
·
生物化学
·
发酵技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）