PREPARATIVE BIOCHEMISTRY & BIOTECHNOLOGY
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2016
·
IF 1.114
Xue-Fang Chen,Chao Huang,Lian Xiong,Bo Wang,Gao-Xiang Qi,Xiao-Qing Lin,Can Wang,Xin-De Chen
Elephant grass (Pennisetum purpureum) dilute acid hydrolysate contains 34.6 g/L total sugars. The potential of lipid production by oleaginous yeast Trichosporon cutaneum grown on elephant grass acid hydrolysate was investigated for the first time. During the fermentation process on the elephant grass acid hydrolysate, glucose, xylose, and arabinose could be well utilized as carbon sources by T. cutaneum. Interestingly, xylose was almost no use before glucose was consumed completely. This illustrated that simultaneous saccharification of xylose and glucose by T. cutaneum did not occur on elephant grass acid hydrolysate. The highest biomass, lipid content, lipid yield, and lipid coefficient of T. cutaneum were measured after the sixth day of fermentation and were 22.76 g/L, 24.0%, 5.46 g/L, and 16.1%, respectively. Therefore, elephant grass is a promising raw material for microbial oil production by T. cutaneum.
研究领域:
生物技术
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2017
·
IF 5.651
Zheng Cheng,Rendang Yang,Xu Liu,Xiao Liu,Hua Chen
Herein, bacterial cellulose (BC) was synthesized by acetobacter xylinum via organic acid pre-hydrolysis liquor of agricultural corn stalk used as carbon source. Acetic acid was applied to pretreat the corn stalk, then, the prehydrolysate was detoxified by sequential steps of activated carbon and ion exchange resin treatment prior to use as carbon source to cultivate acetobacter xylinum. Moreover, the recovery of acetic acid was achieved for facilitating the reduction of cost. The results revealed that the combination method of detoxification treatment was very effective for synthesis of BC, yield could be up to 2.86 g/L. SEM analysis showed that the diameter size of BC between 20 and 70 mm. In summary, the process that bacterial cellulose was biosynthesized via prehydrolysate from agricultural corn stalk used as carbon source is feasible, and the ability to recover organic acid make it economical, sustainable and green, which fits well into the biorefinery concept.
研究领域:
生物技术
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环境科学
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可持续发展
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
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2020
·Vol. 193
·期 1
·205-217
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IF 2.277
Wan Lijun,Gao Zhen,Wu Bin,Cao Fei,Jiang Min,Wei Ping,Jia Honghua
Corncob is an abundant agricultural residue containing high content of hemicellulose. In this paper, the hemicellulosic hydrolysate was prepared from the hydrolysis of corncob using the solid acid sulfated zirconia as a catalyst. According to response surface analysis experiments, the optimum conditions for preparing hemicellulosic hydrolysate catalyzed by sulfated zirconia were determined as follows: solid (sulfated zirconia)–solid (corncob) ratio was 0.33, solid (corncob)–liquid (water) ratio was 0.09, temperature was 153 °C, and time was 5.3 h. Under the optimized conditions, the soluble sugar concentration was 30.12 g/L with a yield of 033 g/g corncob. Subsequently, xylitol production from the resulting hemicellulosic hydrolysate was demonstrated by Candida tropicalis , and results showed that the yield of xylitol from the hemicellulosic hydrolysate could be significantly improved on a basis of decolorization and detoxification before fermentation. The maximum yield of xylitol from the hemicellulosic hydrolysate fermented by C. tropicalis was 0.76 g/g. This study provides a new attempt for xylitol production from the hemicellulosic hydrolysate.
研究领域:
生物化学
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可再生能源
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOPROCESS AND BIOSYSTEMS ENGINEERING
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2025
·
IF 3.6
Yi Xia,Li Xinji,Han Jianqi,Liu Zhidan,Shi Xiaohui,Wen Tao,Zhu Jie
Itaconic acid can be produced using lignocellulosic biomass; however, the inhibitors from pretreatment process of biorefinery are toxic to the fermenting strains. Here, with 35.70 ± 0.69 g/L (0.19 ± 0.05 g/L·h and 73.84 ± 0.01%) itaconic acid from shake flask fermentation of synthetic medium (SM), a newly isolated Aspergillus terreus just produced 1.01 ± 0.01 g/L itaconic acid from corn stover hydrolysates (CSH) for the serious block of aldehyde inhibitors and acetic acid. Convincingly, 25.34 ± 3.94 g/L (0.13 ± 0.02 g/L·h and 37.92 ± 3.89%) itaconic acid was achieved from the detoxified CSH (with residual 0.49 g/L acetic acid) using 4.0% activated charcoal. 21.64 ± 2.42 g/L (0.05 ± 0.01 g/L·h and 26.96 ± 7.81%) itaconic acid was further achieved from CSH for the adapted A. terreus with better degradation ability of furanic aldehydes and phenolic aldehydes. Furthermore, the 108 mutation sites of nine genes from adaptive laboratory evolution (ALE) for A. terreus were further uncovered through single nucleotide polymorphisms (SNPs) analysis, and thus would be responsible for the improved fermentability of itaconic acid from CSH. The current work broke the bottlenecks in itaconic acid fermentation directly from CSH through improving A. terreus using directed evolution technique, and thus would provide a strain biocatalyst A. terreus and establish the alternative strategy to efficiently produce itaconic acid using corn stover. Graphical abstract
研究领域:
生物技术
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发酵工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2013
·
IF 4.75
Jingwen Chen,Yaqin Zhang,Yafei Wang,Xiaosheng Ji,Lin Zhang,Xigeng Mi,He Huang
In this study, vacuum membrane distillation (VMD) was used to remove two prototypical fermentation inhibitors (acetic acid and furfural) from lignocellulose hydrolyzates. The effect of operating parameters, such as feed temperature and feed velocity, on the removal efficiencies of inhibitors was investigated. Under optimal conditions, more than 98% of furfural could be removed by VMD. However, the removal efficiency of acetic acid was considerably lower. After furfural and acetic acid were selectively removed from hydrolyzates by VMD, ethanol production efficiency increased by 17.8% compared to original hydrolyzates.
研究领域:
生物工程
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环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Synthetic Biology
·
2025
·
IF 3.9
Yifan Feng,Wenlong Xiao,Xinyi Li,Weiyu Cao,Yujia Jiang,Wenming Zhang,Wankui Jiang,Fengxue Xin,Min Jiang
Ectoine, a major compatible solute in halophilic micro-organisms, shows great potential in cosmetics and pharmaceuticals areas owing to its water-binding properties and capability to prevent oxidative damage. In this study, the ectABC gene cluster responsible for the ectoine synthesis originated from halophilic bacterium Halomonas venusta was first assembled into Escherichia coli. Subsequently, the crr gene in PTS was knocked out to further drive the metabolic flux from phosphoenolpyruvate to oxaloacetate, resulting in 1.27 g/L of ectoine. Then, the rate-limiting enzyme LysC in the ectoine synthesis pathway was identified and modified. The recombinant E. coli with the further overexpression of feedback-insensitive mutant EclysC* increased the ectoine titer to 2.51 g/L with a yield of 0.37 g/g in shake flasks. After the medium optimization including the carbon and nitrogen source, sodium chloride, and magnesium sulfate concentration, the ectoine titer was improved to 4.55 g/L. 115.15 g/L of ectoine with a yield of 0.23 g/g was obtained in the 5.0 L bioreactor through the optimization of substrate feeding and IPTG supplementation in the fed-batch fermentation. To achieve the cost-effective production of ectoine, lignocellulosic hydrolysate from wheat straw was adopted. 134.08 g/L of ectoine with a yield of 0.33 g/g sugar and a productivity of 3.7 g/L/h was finally produced, representing a relatively high level of ectoine production from renewable resources compared to other studies. This study provides valuable insights into a cost-effective and efficient method for industrial-scale ectoine production.
研究领域:
生物技术
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微生物学
✓ 已验证
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2017
·
IF 5.951
Weiliang Hou,Lang Li,Jie Bao
High product concentration in aerobic biorefining fermentation requires high lignocellulose feedstock loading. However, the high solids content and the consequent high viscosity of the lignocellulose hydrolysate severely limit oxygen transfer and thus lead to low aerobic fermentation rate. This study first investigates the experimental measurement and the computational fluid dynamics (CFD)-based simulation of oxygen transfer properties in the high solids loading and highly viscous lignocellulose hydrolysates. The oxygen mass transfer coefficients kLa values vary with various biorefining processing parameters. A minimum threshold kLa value was required for aerobic fermentation of glucose oxidation into gluconic acid. The rheological properties of the slurry were experimentally determined, and a CFD model was established for the design of aerobic fermentation bioreactors. The kLa values between the CFD calculation and the experimental determination were in good agreement for the high solids loading and highly viscous hydrolysate slurry. The study provided important information and useful tools for achieving efficient aerobic fermentations in high solids loading and highly viscous lignocellulose hydrolysates. The measured kLa value could be applied to general aerobic fermentation using lignocellulose feedstock.
研究领域:
生物工程
·
发酵工程
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2016
·
IF 4.219
Honghua Jia,Tingting Shao,Chao Zhong,Hengxiang Li,Min Jiang,Hua Zhou,Ping Wei
In this paper, we produced hemicellulosic hydrolysate from corncob by tetrabutylammonium hydroxide (TBAH) extraction and dilute acid hydrolysis combined, further evaluating the feasibility of the resultant corncob hemicellulosic hydrolysate used in xylitol production by Candida tropicalis . Optimized conditions for corncob hemicellulose extraction by TBAH was obtained via response surface methodology: time of 90 min, temperature of 60 °C, liquid/solid ratio of 12 (v/w), and TBAH concentration of 55%, resulting in a hemicellulose extraction of 80.07% under these conditions. The FT-IR spectrum of the extracted corncob hemicellulose is consistent with that of birchwood hemicellulose and exhibits specific absorbance of hemicelluloses at 1380, 1168, 1050, and 900 cm −1 . In addition, we found that C. tropicalis can ferment the resulting corncob hemicellulosic hydrolysate with pH adjustment and activated charcoal treatment leading to a high xylitol yield and productivity of 0.77 g/g and 2.45 g/(L h), respectively.
研究领域:
生物化学
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发酵工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2016
·
IF 4.917
Juan Wang,Qiuqiang Gao,Huizhan Zhang,Jie Bao
Oleaginous yeast Trichosporon cutaneum is robust to high levels of lignocellulose derived inhibitor compounds with considerable lipid accumulation capacity. The potential of lipid accumulation of T. cutaneum ACCC 20271 was investigated using corn stover hydrolysates with varying sugar and inhibitor concentrations. Biodiesel was synthesized using the extracted lipid and the product satisfied the ASTM standards. Among the typical inhibitors, T. cutaneum ACCC 20271 is relatively sensitive to furfural and 4-hydroxybenzaldehyde, but strongly tolerant to high titers of formic acid, acetic acid, levulinic acid, HMF, vanillin, and syringaldehyde. It is capable of complete degradation of formic acid, acetic acid, vanillin and 4-hydroxybenzaldehyde. Finally, the inhibitor degradation pathways of T. cutaneum ACCC 20271 were constructed based on the newly sequenced whole genome information and the experimental results. The study provided the first insight to the inhibitor degradation of T. cutaneum and demonstrated the potentials of lipid production from lignocellulose.
研究领域:
微生物学
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生物能源
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Green Energy & Environment
·
2017
·
IF 0
Fen Yue,Christian Marcus Pedersen,Xiuyin Yan,Yequn Liu,Danlei Xiang,Caifang Ning,Yingxiong Wang,Yan Qiao
Hydrothermal carbonization (HTC) is a valuable approach to convert furfural residue (FR) into carbon material. The prepared biochars are usually characterized comprehensively, while the stock process water still remains to be studied in detail. Herein, a NMR study of the main components in stock process water generated at different HTC reaction conditions was reported. Various qualitative and quantitative NMR techniques ( 1 H and 13 C NMR, 1 H– 1 H COSY and 1 H 13 C HSQC etc. ) especially 1D selective gradient total correlation spectroscopy (TOCSY NMR) were strategically applied in the analysis of HTC stock process water. Without separation and purification, it was demonstrated that the main detectable compounds are 5-hydroxymethylfurfural, formic acid, methanol, acetic acid, levulinic acid, glycerol, hydroxyacetone and acetaldehyde in this complicate mixture. Furthermore, the relationship between the concentration of major products and the reaction conditions (180–240 °C at 8 h, and 1–24 h at 240 °C) was established. Finally, reasonable reaction pathways for hydrothermal conversion of FR were proposed based on this result and our previously obtained characteristics of biochars. The routine and challenging NMR methods utilized here would be an alternative other than HPLC or GC for biomass conversion research and can be extended to more studies.
研究领域:
化学工程
·
生物质能研究
✓ 已验证
产品关联
DOI
BIORESOURCE TECHNOLOGY
·
2015
·
IF 4.494
Yan Zhao,Weijia Cao,Zhen Wang,Bowen Zhang,Kequan Chen,Pingkai Ouyang
In this study, Actinobacillus succinogenes NJ113 microbial electrolysis cells (MECs) were used to enhance the reducing power responsible for succinic acid production from corncob hydrolysate. During corncob hydrolysate fermentation, electric MECs resulted in a 1.31-fold increase in succinic acid production and a 1.33-fold increase in the reducing power compared with those in non-electric MECs. When the hydrolysate was detoxified by combining Ca(OH) 2 , NaOH, and activated carbon, succinic acid production increased from 3.47 to 6.95 g/l. Using a constant potential of −1.8 V further increased succinic acid production to 7.18 g/l. A total of 18.09 g/l of succinic acid and a yield of 0.60 g/g total sugar were obtained after a 60-h fermentation when NaOH was used as a pH regulator. The improved succinic acid yield from corncob hydrolysate fermentation using A. succinogenes NJ113 in electric MECs demonstrates the great potential of using biomass as a feedstock to cost-effectively produce succinate.
研究领域:
生物工程
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMASS & BIOENERGY
·
2020
·
IF 3.551
Yun Li,Benkun Qi,Yinhua Wan
Lignocellulose pretreatment results in production of hydrolysate consisting of sugars and inhibitors. Previous reports have shown the viability of nanofiltration (NF) of lignocellulosic hydrolysate for simultaneous sugar concentration and inhibitors removal. However, the complexity of real hydrolysate results in severe membrane fouling which greatly hinders the further application of NF in treating biomass hydrolysate. In this investigation, conditioning of real rice straw hydrolysate from dilute acid pretreatment was conducted by three methods (sedimentation, microfiltration (MF) and activated carbon (AC) adsorption) in order to reduce subsequent NF membrane fouling. Results showed that the turbidity , suspended substance (SS) and particle size of SS of the hydrolysate considerably decreased after these three conditioning methods. Only AC adsorption, however, exhibited best performance in terms of increasing the volume reduction ratio (VRR) and decreasing the membrane fouling during NF filtration of rice straw hydrolysate, demonstrating the effectiveness of AC adsorption for hydrolysate conditioning. Further experiments confirmed that removal of phenolics and pigments , the two dominating foulants during NF process, by AC adsorption were most likely responsible for its superior performance compared to sedimentation and MF.
研究领域:
生物工程
·
环境科学
✓ 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）