Frontiers of Environmental Science & Engineering
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2025
·Vol. 19
·期 6
·1-14
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IF 6.4
Zhang Tengyu,Zhang Jingxin,Zhang Pengshuai,Tong Yen Wah,He Yiliang,Yang Qing
Anaerobic digestion (AD) is a commonly used technology for facilitating carbon fixation by converting complex organic matter into volatile fatty acids and CH 4 ; however, the issue of CO 2 emission remains unresolved in AD. The formation of amorphous carbon has been identified as a more direct method of carbon fixation in AD. This study aimed to elucidate how amorphous carbon can be formed from organic matter or CO 2 by anaerobic microorganisms. The results showed that amorphous carbon was produced in the anaerobic digestion of inorganic and mixed carbon sources, with yields of 0.38 and 3 µg/10 5 cells, respectively. Its characteristics were analyzed using Raman microscopy. Isotope labeling revealed that CO 2 fixation into amorphous carbon primarily depends on the reversed oxidative tricarboxylic acid cycle (roTCA) and hydroxycaproate. Differential pulse voltammetry combined with gene abundance analysis indicated that flavin electron bifurcation (EB) is involved in electron transfer. The microbial isothermal calorimeter further measured the metabolic calorific value, demonstrating that anaerobic microorganisms can autotrophically fix CO 2 with energy provided by EB. Metagenomic analysis supported the large REDOX equivalents input from EB to sustain the roTCA cycle. This research contributes to understanding the mechanism of CO 2 fixation into solid carbon in anaerobic environments. Additionally, it provides new insights into the potential development of carbon-negative technologies in anaerobic biological treatment.
研究领域:
环境科学
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微生物学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yanghao Feng,Wendi Zhang,Kunpeng Tang,Yingzhi Chen,Huiju Cao,Yuan Hu,Weili Cui,Lei Shi,Guowei Yang
Single-walled carbon nanotubes (SWCNTs) serve as ideal templates for synthesizing inner tubes with engineered diameters, resulting in the formation of double-walled carbon nanotubes (DWCNTs). This approach enables the synthesis of confined carbyne (CC) with tailored properties through the newly formed inner tubes. The formation of CC primarily relies on carbon sources derived from the SWCNTs themselves via structure reconstruction under high-temperature annealing, leading to inherently low yield of CC due to insufficient carbon supply. To enhance the yield of CC, we explored the introduction of internal carbon sources, which are small enough to be inserted inside the SWCNTs, such as organic solvents or fullerene molecules; however, further improvements remain challenging. In this study, we demonstrate that incorporating external carbon sources via surfactants on the walls of SWCNTs significantly increases the yield of CC. The surfactants decompose at high temperatures, releasing carbon atoms that integrate into both the DWCNT structure and the CC; thus, the Raman intensity of CC increased by approximately 2.1 times compared to the empty counterpart. Moreover, combination of external surfactants and internal C 70 results in an ultrahigh Raman intensity of CC, exhibiting value approximately 30 times greater than that of the pristine SWCNTs. These findings underscore the potential of engineered both external and internal precursors to boost the synthesis of CC, benefiting their applications.
研究领域:
材料科学
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纳米技术
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2014
·
IF 2.307
Yinsheng Li,Jie Yin,Haibo Wu,Ping Lu,Yongjie Yan,Xuejian Liu,Zhengren Huang,Dongliang Jiang
In order to attain high thermal conductivity , SiC was doped with ultra-low amounts of B and C as sintering additives using boric acid together with d -fructose as boron–carbon sources. The contents of in situ generated B and C were both tailored as low as 0.4 wt.%, which can significantly reduce the impurities induced phonon scattering effect. The SiC ceramics were pressureless densified at 2150 °C for 1 h, and some samples experienced subsequent annealing at 1950 °C for 4 h. High thermal conductivities of 180.94 W/(m K) for the as-sintered SiC ceramics and 192.17 W/(m K) for the annealed specimens at room temperature were achieved. The reasons for the high thermal conductivity in the polycrystalline SiC ceramics were specified, based on the close correlation with microstructure.
研究领域:
材料科学
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陶瓷工程
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产品关联
DOI
高影响因子
Environmental Science-Processes & Impacts
·
2019
·Vol. 22
·期 1
·197-206
·
IF 2.688
Changwei Li,Xianwang Kong,Lihua Lan,Musa Abubakar Tadda,Dezhao Liu
17β-estradiol (E2) ubiquitously exists in various water bodies with long-term endocrine-disrupting and carcinogenic impacts on wildlife even at the trace level of ng L−1. However, it remains unclear how easy-to-degrade carbon sources alter E2 biodegradation patterns. In this study, E2 biodegradation by Sphingomonas sp. MCCC 1A06484 was investigated with regard to alternative carbon sources. Results showed that the bacterium preferentially utilized glucose, sodium succinate and sodium acetate over E2. Interestingly, the presence of these preferred nutrients increased the E2 removal efficiency by 20.1%. Furthermore, a positive relation (p < 0.05) between the utilization of total organic carbon (TOC) and E2 was found. Using intracellular metabolomics by UHPLC-QTOF-MS, 11 up-regulated and 35 down-regulated metabolites (variable importance > 1, p < 0.05) were identified in the bacterium when cultivated with E2 under various carbon and nitrogen backgrounds. The E2 exposure contributed to metabolism changes of lipid, nucleotide, carbohydrate, amino acid and membrane transport, which were considered to play roles in the E2 metabolism. The up-regulated phosphatidylcholine might act as an indicator during the bacterial degradation of E2. Generally, this study contributes to an in-depth understanding of E2 biodegradation in complex environments with multiple carbon and nitrogen sources.
研究领域:
环境科学
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微生物学
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2023
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IF 6.1
Simin Liu,Jiamei Liu,Linguo Zhao,Jianjun Pei
Glycosylation, one of the most common and significant modifications in nature, has prompted the development of a cellobiose phosphorolysis route for glycosylation in vivo. However, the process of glycosylation is hampered by the notably low conversion rate of cellobiose. In this work, regulation of the carbon source supply by changing the ratio of glucose to cellobiose improved the conversion rate of cellobiose, resulting in enhancing the efficiency of glycosylation and the production of vitexin. Moreover, three genes (pgm, agp, and ushA) involved in the degradation of UDP-glucose were knocked out to relieve the degradation and diversion of the cellobiose phosphorolysis route. Finally, through the optimization of conversion conditions, we observed a continuous enhancement in cellobiose conversion rate and vitexin production in BL21ΔushAΔagp-TcCGT-CepA, corresponding to an increased concentration of added glucose. The maximum production of vitexin reached 2228 mg/L with the addition of 2 g/L cellobiose and 6 g/L glucose, which was 312% of that in BL21-TcCGT-CepA with the addition of 2 g/L cellobiose. The conversion rate of cellobiose in BL21ΔushAΔagp-TcCGT-CepA reached 88%, which was the highest conversion rate of cellobiose to date. Therefore, this study presents a cost-effective and efficient method to enhance the conversion rate of cellobiose during the glycosylation process.
研究领域:
生物化学
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代谢工程
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产品关联
DOI
PubMed
高影响因子
Frontiers in Microbiology
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2023
·
IF 5.2
Wang Junqi,Liu Meijie,Mao Chengzhi,Li Sizhu,Zhou Jiabao,Fan Yaqin,Guo Lizhong,Yu Hao,Yang Xiuqing
Cyclosporine A (CsA) is a secondary cyclopeptide metabolite produced by Tolypocladium inflatum that is widely used clinically as an immunosuppressant. CsA production and mycelial growth differed when T. inflatum was cultured in different carbon source media. During early fermentation, CsA was preferred to be produced in fructose medium, while the mycelium preferred to accumulate in sucrose medium. On the sixth day, the difference was most pronounced. In this study, high-throughput comparative proteomics methods were applied to analyze differences in protein expression of mycelial samples on day 6, revealing the proteins and mechanisms that positively regulate CsA production related to carbon metabolism. The differences included small molecule acid metabolism, lipid metabolism, organic catabolism, exocrine secretion, CsA substrate Bmt synthesis, and transcriptional regulation processes. The proteins involved in the regulation of mycelial growth related to carbon metabolism were also revealed and were associated with waste reoxidation processes or coenzyme metabolism, small molecule synthesis or metabolism, the stress response, genetic information or epigenetic changes, cell component assembly, cell wall integrity, membrane metabolism, vesicle transport, intramembrane localization, and the regulation of filamentous growth. This study provides a reliable reference for CsA production from high-efficiency fermentation. This study provides key information for obtaining more CsA high-yielding strains through metabolic engineering strategies.
研究领域:
微生物学
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药理学
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生物化学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Jing Jiang,Xinwei Li,Kaiguang Yang,Wangyin Wang,Xupeng Cao,Can Li
Formate, which can be produced from CO 2 with green energy, has received increasing attentions as a carbon source for bioconversion. Microalgae have the native advantages of use captured light energy to facilitate the formate assimilation. However, the low efficient natural conversion and inhibition to the electron transfer chain obstacle its applications’ development. Here, using green microalga C. reinhardtii 21gr as the model, an approach to improve formate-based biomass and protein production was raised and verified through isotope labeling experiments, and the pathway of formate which presented in photosynthetic organisms was related to amino acids. By the enhancement of chloroplast glyceraldehyde-3-phosphate dehydrogenase (cGAPDH) expression, together with the adaptive laboratory evolution (ALE) over regular lethal dose of formate, the yields of the biomass and proteins were promoted with 34 % and 55 % to the wild type, respectively. Indicated by the photosynthetic activity variations, it was proposed that the balance of cellular energy and reduction power is necessary for microalgae to achieve high productivity with formate. Further investigated by proteomics, 6-phosphogluconate dehydrogenase (6-PGD) was identified as the key enzyme to formate and nitrogen’s co-assimilation.
研究领域:
植物学
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生物化学
·
遗传学
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DOI
高影响因子
ELECTROCHIMICA ACTA
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2019
·
IF 5.383
Hui Zhuang,Yubo Bao,Yake Nie,Yunxian Qian,Yuanfu Deng,Guohua Chen
To overcome the problems faced by the preparation of high-performance LiFe 0.5 Mn 0.5 PO 4 /C cathode material for commercial application in large scale, such as complicated procedures in the synthesis process and/or low volumetric energy density of nanometer-sized sample, herein, micro-agglomerated LiFe 0.5 Mn 0.5 PO 4 /C is prepared by a facile surfactant-assisted solid-state route. A composite carbon source and controllable pre-calcining process are used for achieving the homogenous carbon coating, interconnected pores and uniform particle size distribution . X -ray powder diffraction, Raman spectrum , N 2 -adsorpotion-desorpotion, scanning/transmission electron microscopy and elemental analysis confirm the microstructure and accurate composition of the as-prepared samples. It is found that the composite source not only increases the homogeneity of the carbon coating layer and the pore-forming ability, but also contributes to inhibiting the size growth of the primary particles. Meanwhile, the suitable pre-calcining time can improve the specific surface area and optimize the carbon content and pore structure , and thus enhance the tap density of the as-prepared material. The typical LiFe 0.5 Mn 0.5 PO 4 /C sample with carbon content of 3.50 wt% displays high reversible capacities and good rate capability, with discharge capacities of 155.0, 141.5 and 120.1 mA h g −1 at 0.1, 1.0 and 5.0 C (1 C = 170 mA g −1 ), respectively. Furthermore, the sample exhibits superior cycling performance, with a capacity retention above 98% after 200 cycles at 1.0 and 5.0 C. As a result, this LiFe 0.5 Mn 0.5 PO 4 /C exhibits great potential as a cathode material for high power/energy lithium ion batteries because of its easy synthesis, high specific capacity, good rate capability and cycle stability.
研究领域:
材料科学
·
能源存储与转换
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DOI
高影响因子
Biotechnology for Biofuels and Bioproducts
·
2024
·Vol. 17
·期 1
·1-17
·
IF 3.3
Liu Lin,Wang Zhixing,Fang Yu,Yang Renfei,Pu Yi,Meng Xiangfeng,Liu Weifeng
Background The saprophytic filamentous fungus Trichoderma reesei represents one of the most prolific cellulase producers. The bulk production of lignocellulolytic enzymes by T. reesei not only relies on the efficient transcription of cellulase genes but also their efficient secretion after being translated. However, little attention has been paid to the functional roles of the involved secretory pathway in the high-level production of cellulases in T. reesei. Rab GTPases are key regulators in coordinating various vesicle trafficking associated with the eukaryotic secretory pathway. Specifically, Rab7 is a representative GTPase regulating the transition of the early endosome to the late endosome followed by its fusion to the vacuole as well as homotypic vacuole fusion. Although crosstalk between the endosomal/vacuolar pathway and the secretion pathway has been reported, the functional role of Rab7 in cellulase production in T. reesei remains unknown.Results A TrRab7 was identified and characterized in T. reesei. TrRab7 was shown to play important roles in T. reesei vegetative growth and vacuole morphology. Whereas knock-down of Trrab7 significantly compromised the induced production of T. reesei cellulases, overexpression of the key transcriptional activator, Xyr1, restored the production of cellulases in the Trrab7 knock-down strain (Ptcu-rab7KD) on glucose, indicating that the observed defective cellulase biosynthesis results from the compromised cellulase gene transcription. Down-regulation of Trrab7 was also found to make T. reesei more sensitive to various stresses including carbon starvation. Interestingly, overexpression of Snf1, a serine/threonine protein kinase known as an energetic sensor, partially restored the cellulase production of Ptcu-rab7KD on Avicel, implicating that TrRab7 is involved in an energetic adaptation to carbon starvation which contributes to the successful cellulase gene expression when T. reesei is transferred from glucose to cellulose.Conclusion sTrRab7 was shown to play important roles in T. reesei development and a stress response to carbon starvation resulting from nutrient shift. This adaptation may allow T. reesei to successfully initiate the inducing process leading to efficient cellulase production. The present study provides useful insights into the functional involvement of the endosomal/vacuolar pathway in T. reesei development and hydrolytic enzyme production.
研究领域:
微生物学
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分子生物学
·
酶工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2021
·
IF 6.953
Ali Mohsin,Kanagat Akbota Akyliyaevna,Waqas Qamar Zaman,Muhammad Hammad Hussain,Muhammad Zubair Mohsin,Sarah Al-Rashed,Xin Tan,Xiwei Tian,Kistaubayeva Aida,Muhammad Tariq,Muhammad Salman Haider,Imran Mahmood Khan,Sobia Niazi,Yingping Zhuang,Meijin Guo
The present study emphasizes improving the overall yield, productivity and quality of xanthan by Xanthomonas campestris using different carbon sources via optimizing the fermentation media and kinetic modelling work. After optimization, six carbon sources and one nitrogen source were selected for xanthan production in 5 L bioreactor. Kinetic modelling was applied to assess the experimental fermentation data and to check its influence on scale-up production. In this work, xanthan production reached 40.65 g/L with a growth-associated rate constant (α) of 2.831, and highest specific growth rate (μm) of 0.37/h while using maltose as the sole carbon source. Furthermore, rheological properties were determined, and Herschel-Bulkley model was employed to assess the experimental data. Interestingly, xanthan obtained from sucrose and glucose showed the highest yield stress (τ 0 ) of 12.50 ± 0.31 and 7.17 ± 0.21. Moreover, the highest xanthan molecular weight of 3.53 × 10 7 and 3.25 × 10 7 g/mol were also found with sucrose and glucose. At last, the proposed mechanism of sugar metabolism and xanthan biosynthesis pathway were described. Conclusively, maltose appeared as the best carbon source for maximum xanthan production: while sucrose and glucose gave qualitatively best results. In short, this systematically modelled approach maximizes the potential output and provides a solid base for continuous cultivation of xanthan at large-scale production.
研究领域:
微生物学
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生物工程
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产品关联
DOI
PubMed
高影响因子
CARBON
·
2023
·
IF 10.9
Bin Han,Hanxiang Mu,Jingyi Chen,Xiaodong Hao,Hongyue Wang,Peng Liu,Bingshe Xu,Shufang Ma,Yingjun Yang,Tian Wang,Shukai Ding,Christophe A. Serra,Gaohui Du
Hybrid graphene interdigital electrode-perovskite structure has demonstrated high value in the photodetector (PD) due to high absorbance and carrier collection efficiency. However, direct pattern of graphene film on the dielectric substance still faces huge challenges. Especially, the involvement of multi-step transfer and high-energy etching process hamper its development. In this context, we propose an organic nano carbon source (ONCS). Direct pattern of graphene film on the quartz substrate (GFqtz) is attained by the calcination of patterned ONCS film for the first time, which is simply achieved by screen printing technology thanks to the gel state. The transformation mechanism from ONCS to GFqtz has been proposed. In detail, the ONCS in-situ react with the quartz substrate to induce the SiC nanocrystals layer during the calcination. Then, the graphene film composes of the non-ordered graphene crystal layer and the aligned graphene crystals layer. Finally, the perovskite PD are successfully constructed by the GFqtz interdigital electrode. Compared to the PD fabricated by the Au interdigital electrode, the GFqtz-perovskite PD present an ultra-low detective light power density (0.5 μW/cm 2 ) at 1 V bias voltage. The maximum responsivity and defectivity (0.1 A/W) and D* (2.6 × 10 11 Jones) of the GFqtz-perovskite PD demonstrate an order of magnitude higher than the Au-perovskite PD's value.
研究领域:
材料科学
·
光电技术
·
纳米技术
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产品关联
DOI
高影响因子
Small Methods
·
2023
·Vol. 7
·期 3
·2201596
·
IF 12.4
Yujun Wu,Yifei Yuan,Wei Shuang,Liguang Wang,Lin Yang,Zhengyu Bai,Jun Lu
Novel methods and mechanisms for graphene fabrication are of great importance in the development of materials science. Herein, a facile method to directly convert carbonaceous salts into high-quality freestanding graphene via a simple one-step redox reaction, is reported. The redox couple can be a combination of sodium borohydride (reductant) and sodium carbonate (oxidant), which can readily react with each other when evenly mixed/calcined and yield gram-scale, high-quality, contamination-free, micron-sized, freestanding graphene. More importantly, this method is applicable to a variety of input reductants and oxidants that are low cost and easily accessible. An in-depth investigation reveals that the carbonaceous oxidants can not only provide reduced carbon mass for graphene formation but also act as a self-template to guide the polymerization of carbon atoms following the pattern of the monolayer, six-carbon rings. In addition, the direct formation of graphene exhibits theoretically lower energy barriers than that of other allotropes such as fullerene and carbon nanotube. This facile, low-cost, scalable, and applicable method for mass production of high-quality graphene is expected to revolutionize graphene fabrication technology and boost its practical application to the industry level.
研究领域:
材料科学
·
化学工程
✓ 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）