APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
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2021
·Vol. 193
·期 11
·3469-3482
·
IF 2.926
Li Hailong,Chen Xindong,Wang Can,Chen Xuefang,Guo Haijun,Xiong Lian,Zhang Hairong,Huang Chao,Chen Xinde
Understanding factors that affect the catalytic efficiency and synergism of enzymes is helpful to enhance the process of bioconversion. In this study, birch wood (BW) was sequentially treated by delignification (DL), deacetylation (DA), and decrystallization (DC) treatments. The physiochemical structures of treated BW were characterized. Moreover, the influences of sequential treatments on the catalytic efficiency and synergism of xylanase and cellulase were studied. DL treatments efficiently improved the conversion of cellulose and xylan. A high degree of synergy (DS) between xylanase and cellulase was produced during hydrolysis of DL-treated BW. DA treatments enhanced xylan conversion but reduced the DS between xylanase and cellulase for xylan hydrolysis, whereas DC treatments enhanced cellulose conversion but reduced the DS between xylanase and cellulase for cellulose hydrolysis. The cellulose conversion of lithium chloride/N,N-dimethylacetamide (LiCl/DMAc)-treated BW (89.69%) was higher than the cellulose conversion of ball milling (BM)-treated BW (81.63%), whereas the xylan conversion of LiCl/DMAc-treated BW (83.77%) was lower than the xylan conversion of BM-treated BW (87.21%). This study showed that the catalytic efficiency and synergism of xylanase and cellulase are markedly affected by lignin hindrance, hemicellulose acetylation, and cellulose crystallization. Graphical abstract
研究领域:
生物化学
·
可再生资源与环境工程
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DOI
高影响因子
ACS Applied Bio Materials
·
2020
·
IF 0
Shuting Lu,Xiaocheng Fan,Henan Wang,Yuliang Zhao,Wancheng Zhao,Mengzhu Li,Rongyao Lv,Ting Wang,Tiedong Sun
Betulinic acid (BA) is a natural antitumor agent and has biological activity against multiple human tumor cell lines with low cytotoxicity to normal cells, while the high hydrophobicity and the short half-life of this compound limit its clinical application. Here, gelatin-based dual-targeted nanoparticles of BA are promising to solve this problem. Hydrophobic BA is loaded in cyclodextrin to increase its solubility and prolong the circulation time in vivo. The nanoscale drug delivery systems can further enhance the bioavailability and the antitumor effect of BA and are passively targeted to the tumor tissue sites by enhanced permeability and retention effect. The RGD sequence of gelatin specifically recognizes tumor cells and brings agents into tumor cells. The nanoparticles were characterized by transmission electron microscopy, Fourier transform infrared, nuclear magnetic resonance, etc. In addition, we observed antitumor activity of the nanoparticles using both cell-based assays and mouse xenograft tumors, which proved that betulinic acid/gelatin-γ-cyclodextrin nanoparticles had a better tumor inhibition effect than betulinic acid/γ-cyclodextrin inclusion compound.
研究领域:
药剂学
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肿瘤学
·
生物材料学
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DOI
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS
·
2022
·Vol. 110
·期 8
·1789-1795
·
IF 3.405
Xuan Chen,Shuting Lu,Fengrong Gong,Xiaoyu Sui,Tingting Liu,Ting Wang
Betulinic acid (BA), a natural pentacyclic lupine-type triterpene, has shown its prominent efficiency on the selective antitumor activity. However, its poor water solubility and bioavailability have limited its application. Herein, targeting nanoparticles were prepared to improve BA-based liposome (BL)'s restricted chemotherapeutic efficacy. Multi-layers membranes from the cancer cells were added as highly penetrative targeting ligands to functionalize the BA-based liposomes. In vitro experiments including the MTT assay and the fluorescence imaging of live/dead staining were adopted to prove its great inhibition in the growth of tumor cells. And it manifests that the antitumor efficacy of BL coated with cell membranes (BLCM) achieves nearly 4.3 times as that of BL under the same conditions in the MTT experiments. In addition, the fluorescence imaging stained with DAPI-FITC was applied to prove the targeting positioning effects on the BLCM. In a nutshell, the nanomedicine has good targeting antitumor efficacy and has great potential in being applied for the personalized cancer clinical treatment.
研究领域:
药理学
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纳米医学
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肿瘤学
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产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2020
·Vol. 25
·期 4
·948
·
IF 3.267
Yuqin Yang,Tianxin Xie,Xuehao Tian,Nana Han,Xiaojing Liu,Hongshan Chen,Jinchai Qi,Feng Gao,Wen Li,Qianwen Wu,Su Huo,Yuhao Gu,Ziqi Dai,Penglong Wang,Haimin Lei
Betulinic acid (BA) is a star member of the pentacyclic triterpenoid family, which exhibits great prospects for antitumor drug development. In an attempt to develop novel antitumor candidates, 21BA-nitrogen heterocyclic derivatives were synthetized, in addition to four intermediates, 23 of which were first reported. Moreover, they were screened for in-vitro cytotoxicity against four tumor cell lines (Hela, HepG-2, BGC-823 and SK-SY5Y) by a standard methylthiazol tetrazolium (MTT) assay. The majority of these derivatives showed much stronger cytotoxic activity thanBA. Remarkably, the most potent compound7e(the half maximal inhibitory concentration (IC50) of which was 2.05 ± 0.66 μM) was 12-fold more toxic in vitro thanBA-treated Hela. Furthermore, multiple fluorescent staining techniques and flow cytometry collectively revealed that compound7ecould induce the early apoptosis of Hela cells. Structure–activity relationships were also briefly discussed. The present study highlighted the importance of introducing nitrogen heterocyclic rings into betulinic acid in the discovery and development of novel antitumor agents.Keywords:betulinic acid;BA-nitrogen heterocyclic derivatives;antitumor;Hela;flow cytometry
研究领域:
药物化学
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肿瘤学
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2018
·
IF 3.412
Huafang Ding,Xiaqing Wu,Junhui Pan,Xing Hu,Deming Gong,Guowen Zhang
Betulinic acid (BA), an important pentacyclic triterpene widely distributed in many foods, possesses high antidiabetic activity. In this study, BA was found to exhibit stronger inhibition of α-glucosidase than acarbose with an IC50 value of (1.06 ± 0.02) × 10–5 mol L–1 in a mixed-type manner. BA bound with α-glucosidase to form a BA−α-glucosidase complex, resulting in a more compact structure of the enzyme. The obtained concentrations and spectra profiles of the components resolved by the multivariate-curve resolution–alternating least-squares confirmed the formation of the BA−α-glucosidase complex. Molecular docking showed that BA tightly bound to the active cavity of α-glucosidase, which might hinder the entrance of the substrate leading to a decline in enzyme activity. The chemical modification of α-glucosidase verified the results of the computer simulation that the order of importance of the four amino acid residues in the binding process was His > Tyr > Lys > Arg.
研究领域:
药理学
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生物化学
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计算生物学
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产品关联
DOI
PubMed
高影响因子
European Journal of Wood and Wood Products
·
2024
·Vol. 83
·期 1
·1-10
·
IF 2.4
Feng Fuqi,Bai Jiangling,Peng Jinda,He Lei,Liu Fangfang,Ma Yuanyuan,Da Guowei,Wei Chenzhuo,Lei Jiuli,Cui Juqing
Wood is an eco-friendly and renewable natural material. However, it cannot be easily shaped for curved products with mold-pressing technology while maintaining its intrinsic properties. In this study, different delignification treatments (acid, alkali, and combined acid–alkali) were applied to birch veneer for the manufacturing of highly curved laminated veneer lumber (LVL). The physical properties, including color, shrinkage, density, and mass loss, of treated birch veneers changed significantly after the delignification treatment. Characterization of lignin content and FTIR showed partial removal of lignin and hemicellulose. The crystallinity of treated birch veneer, calculated from XRD data, increased due to the reduction of the non-crystalline regions. SEM demonstrated that birch veneer and acid-treated veneer contain many hollow vessel structures and fibers, while alkali-treated and acid–alkali-treated veneers observed completely closed fibers. The magnified examination of alkali-treated birch veneer reveals a completed and smoothed crease, whereas acid–alkali-treated veneers exhibit rough creases with loose fibers. In contrast, untreated birch veneer and acid-treated veneers tend to fracture upon folding. Finally, highly curved LVL with minimal angles of 30° was prepared with alkali-treated veneers. Compressive performance increases from 8.7 MPa for curved LVL with angles of 120° to 19.8 MPa for curved LVL with angles of 30°. These findings could be used to manufacture shaped furniture, irregular building formwork, reconstituted decorative lumber and automobile interiors in the future.
研究领域:
木材科学
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材料工程
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产品关联
DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
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2021
·
IF 5.89
Miao Ting,Basit Abdul,Liu Junquan,Zheng Fengzhen,Rahim Kashif,Lou Huiqiang,Jiang Wei
Xylanases with high specific activity has been focused with great interest as a useful enzyme in biomass utilization. The production of recombinant GH11 xylanase (MYCTH_56237) from Myceliophthora thermophila has been improved through N-terminal signal peptide engineering in P. pastoris. The production of newly recombinant xylanase (termed Mtxyn11C) was improved from 442.53 to 490.7 U/mL, through a replacement of α-factor signal peptide with the native xylanase signal peptide segment (MVSVKAVLLLGAAGTTLA) in P. pastoris. Scaling up of Mtxyn11C production in a 7.5 L fermentor was improved to the maximal production rate of 2503 U/mL. In this study, the degradation efficiency of Mtxyn11C was further examined. Analysis of the hydrolytic mode of action towards the birchwood xylan (BWX) revealed that Mtxyn11C was clearly more effective than commercial xylanase and degrades xylan into xylooligosaccharides (xylobiose, xylotriose, xylotetraose). More importantly, Mtxyn11C in combination with a single multifunctional xylanolytic enzyme, improved the hydrolysis of BWX into single xylose by 40%. Altogether, this study provided strategies for improved production of xylanase together with rapid conversion of xylose from BWX, which provides sustainable, cost-effective and environmental friendly approaches to produce xylose/XOSs for biomass energy or biofuels production.
研究领域:
生物技术
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酶学
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生物化学工程
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Xiangyu Wang,Lifeng Li,Xinyi Xie,Xinping Ouyang,Xueqing Qiu,Qinzhen Fan,Lihua Cheng
The fractionation of lignocellulose is the key step for its efficient utilization. A mild fractionation process was proposed for producing glucan oligomers and high purity lignin using ZnBr 2 molten salt hydrate (ZnBr 2 -MSH). It was found that the cellulose could be hydrolyzed rapidly using ZnBr 2 -MSH with a slight amount of acid (ZnBr 2 -AMSH), giving as high as 88.0 % yield of glucan oligomers together with 92.4 % purity of lignin at 90 °C for 20 min. The long-time molecular dynamics simulation indicated that ZnBr 2 -MSH had more free Br ions to form hydrogen bonds (H-bonds) with H atom in hydroxyl and Zn ions with stronger coordination ability to O atoms in hydroxyl, and hence exhibited that stronger ability to destruct the H-bonds among cellulose bundles. Therefore, ZnBr 2 -MSH could deconstruct cellulose crystal under mild conditions. The lignin obtained by fractionation of ZnBr 2 -AMSH contained more polar functional groups, demonstrating its potential application in a binder for hard carbon (HC) anode in sodium-ion battery, and the resultant electrode contributed to good electrochemical performances and cycling stability. This research work provides a promising approach for efficient fractionation and application of the three components in lignocellulose.
研究领域:
生物质化学
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材料科学
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能源科学
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产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Abdul Basit,Ting Miao,Junquan Liu,Jiaqi Wen,Lina Song,Fengzhen Zheng,Huiqiang Lou,Wei Jiang
Here, we report highly efficient degradation of xylan into xylose by a single multifunctional xylanolytic enzyme from the filamentous fungus Thermothelomyces thermophila (termed Ttxy43). Ttxy43 shows three different enzyme activities toward carbohydrates, β-xylosidase (80.8 U/mg), endoxylanase (105.42 U/mg), and α-l-arabinofuranosidase enzyme activities (15.81 U/mg). Analysis of the catalytic mode of action of Ttxy43 for birchwood-xylan (BWX) reveals that endoxylanase initially degrades xylan to unbranched xylooligosaccharides (XOSs) (xylobiose, xylotriose, xylotetraose) as intermediates, which are then quickly hydrolyzed into single xylose by β-xylosidase. Site-directed mutagenesis studies indicate that Ttxy43 residues Asp134 and Glu228 are essential catalytic sites, while Glu176, Asp38, and Asp85 play an accessory role. More importantly, Ttxy43 displays higher degradation efficiency in comparison with a commercial β-xylosidase and endoxylanase “cocktail”. These findings elucidate an efficient integrated degradation mechanism of xylan under industrial reaction conditions, which provides a novel strategy to design techniques for biomass energy production.
研究领域:
生物化学
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生物技术
·
酶学
·
可再生能源
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产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Shitong Yu,Pan Xu,Zhicheng Luo
Converting lignin into renewable fuels via hydrogenolysis is crucial for achieving carbon neutrality. Existing methods primarily produce monomers in the carbon range of 6–9, inadequate for sustainable aviation fuels requiring heavier components. This study introduces a Ni/Nb 2 O 5 catalyst for catalytic transfer hydrogenolysis of organosolv birch lignin with isopropanol, predominantly resulting in dimers and trimers within carbon ranges of 8–16 and 16–30, comprising 24.7 % and 60.5 % of the lignin-oil, respectively. The catalyst's oxygen vacancies and acid sites facilitate efficient C-O and C-C bonds cleavage, preserving a highly aromatic structure with reduced O/C ratio, elevated H/C ratio, and decreased unsaturation. Characterization techniques confirm a significant 55.5 % deoxygenation degree of the lignin-oil, making it suitable for the synthesis of customized fuel across various carbon numbers. This approach offers a practical pathway for obtaining renewable heavier fuel components and precursors from lignin, significantly advancing sustainable fuel technologies.
研究领域:
化学工程
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可再生能源
·
催化
·
可持续燃料
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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）