Biotechnology for Biofuels
·
2019
·Vol. 12
·期 1
·1-18
·
IF 5.452
Pang Yaru,Zhao Yakun,Li Shenglong,Zhao Yu,Li Jian,Hu Zhihui,Zhang Cuiying,Xiao Dongguang,Yu Aiqun
Background Limonene is an important biologically active natural product widely used in the food, cosmetic, nutraceutical and pharmaceutical industries. However, the low abundance of limonene in plants renders their isolation from plant sources non-economically viable. Therefore, engineering microbes into microbial factories for producing limonene is fast becoming an attractive alternative approach that can overcome the aforementioned bottleneck to meet the needs of industries and make limonene production more sustainable and environmentally friendly. Results In this proof-of-principle study, the oleaginous yeast Yarrowia lipolytica was successfully engineered to produce both d -limonene and l -limonene by introducing the heterologous d -limonene synthase from Citrus limon and l -limonene synthase from Mentha spicata , respectively. However, only 0.124 mg/L d -limonene and 0.126 mg/L l -limonene were produced. To improve the limonene production by the engineered yeast Y. lipolytica strain, ten genes involved in the mevalonate-dependent isoprenoid pathway were overexpressed individually to investigate their effects on limonene titer. Hydroxymethylglutaryl-CoA reductase (HMGR) was found to be the key rate-limiting enzyme in the mevalonate (MVA) pathway for the improving limonene synthesis in Y. lipolytica . Through the overexpression of HMGR gene, the titers of d -limonene and l -limonene were increased to 0.256 mg/L and 0.316 mg/L, respectively. Subsequently, the fermentation conditions were optimized to maximize limonene production by the engineered Y. lipolytica strains from glucose, and the final titers of d -limonene and l -limonene were improved to 2.369 mg/L and 2.471 mg/L, respectively. Furthermore, fed-batch fermentation of the engineered strains Po1g KdHR and Po1g KlHR was used to enhance limonene production in shake flasks and the titers achieved for d -limonene and l -limonene were 11.705 mg/L (0.443 mg/g) and 11.088 mg/L (0.385 mg/g), respectively. Finally, the potential of using waste cooking oil as a carbon source for limonene biosynthesis from the engineered Y. lipolytica strains was investigated. We showed that d -limonene and l -limonene were successfully produced at the respective titers of 2.514 mg/L and 2.723 mg/L under the optimal cultivation condition, where 70% of waste cooking oil was added as the carbon source, representing a 20-fold increase in limonene titer compared to that before strain and fermentation optimization. Conclusions This study represents the first report on the development of a new and efficient process to convert waste cooking oil into d -limonene and l -limonene by exploiting metabolically engineered Y. lipolytica strains for fermentation. The results obtained in this study lay the foundation for more future applications of Y. lipolytica in converting waste cooking oil into various industrially valuable products.
研究领域:
生物技术
·
代谢工程
·
微生物学
·
可持续化学
·
生物化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD HYDROCOLLOIDS
·
2024
·
IF 11
Ruican Wang,Richard W. Hartel,Xinyu Zhai,Wenhui Fu,Yi Sun,Shuo Wang
Phase separation is a prevalent phenomenon in gummy confections, often arising from potential molecular incompatibility between gelatin and long-chain polysaccharides in glucose syrups (GS). This study focuses on analyzing the phase separation and gelling behaviors of gelatin-GS mixtures, elucidating the roles played by water content and small molecular weight (MW) additional ingredients. Mixtures with 6% gelatin, 40% GS, and varying portions of water, sucrose/allulose, citric acid (CA), and citrates (soluble/insoluble) were prepared. Phase separation behaviors were observed using inverted fluorescent microscopy, with the gel properties characterized using rheology, texture profile analysis (TPA), and water-holding capacity (WHC) analysis. The results highlight the significant impacts of these small MW components on biopolymer compatibility (cosolubility). In gelatin-GS-water mixtures, reducing the water ratio without the addition of sugars promoted phase separation towards the polysaccharide-rich morphologies, while enhancing the sol-gel transition and gel strength due to increased gelatin/water ratio. The incorporation of sucrose or allulose into gelatin-GS-water mixtures, without altering the gelatin/GS/water ratio, generally improved the protein-polysaccharide co-solubility during mixing but had an adverse overall effect on gel formation. Acidification with CA increased the surface charges of the proteins, enhancing the biopolymer miscibility and gelling performance. Soluble citrates, e.g., sodium citrate (SC) and potassium citrate (PC), promoted protein-polysaccharide miscibility and gelation at low concentrations (1–5%), but led to severe phase separation and weakened gelation at higher dosage levels (7.5–10%). In contrast, insoluble citrate, i.e., calcium citrate (CC), marginally enhanced the protein-polysaccharide miscibility while facilitating gummy gelation as an active filler.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2022
·
IF 5.546
Kai-Xuan Qin,Shi-Si Li,Jing Xu,Zi-Long Li,Zi-Chen Li,Chunzu Cheng
Independence of food supply chain is a grand challenge encountered by the development of bio-based polymers. Here, we demonstrate the synthesis of amorphous aliphatic polyesters via organocatalyzed ring-opening polymerization of 9-membered lactone monomer, a novel downstream product of non-edible citronella oil. In particular, chemical transformation of trisubstituted alkene moiety owned by this renewable biomass was achieved by cross-metathesis of this bulky group with methyl acrylate . Three-armed star polymers were converted to free-standing films by UV-induced crosslinking. In particular, these crosslinked thin films could be efficiently recycled as ω -hydroxy ester upon methanolysis. This work opens a new avenue for the synthesis and application of terpene- and terpenoid-based polymers.
研究领域:
材料科学
·
绿色化学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2024
·
IF 4
Nawei Zhang,Yang Xu,Xiao Li,Jingnan Ren,Xiao Jia,Siyi Pan,Zhenglun Li,Xiang He,Zhaoxing Hu,Gang Fan
Formation of delayed bitterness is an intractable problem in the processing of citrus juice. This study analyzed the distribution of main bitter-causing substances in sweet orange and the effect of heat treatment, storage temperature, clarification, and homogenization on the limonin content in sweet orange juice. The segment membrane accounted for 34–42% of limonin in the fruit and 21–45% of limonoate A-ring lactone (LARL). Heat treatment accelerated the formation of limonin in juice. Pectinase treatment appeared to facilitate the formation of limonin by reducing the pH of juice. In addition, refrigeration at 4 °C was found to restrain the formation of limonin in juice by inhibiting the activity of limonin D-ring lactone hydrolase (LDLH). In conclusion, segment membrane may have a great contribution to the delayed bitterness of sweet orange juice due to its abundant LARL. These results may provide some guidance for citrus processing and bitterness removal.
研究领域:
食品科学
·
植物生理学
·
食品加工
✓ 已验证
产品关联
DOI
高影响因子
ACS Central Science
·
2024
·
IF 12.7
Xiangfeng Meng,Yue Zhou,Lei Xu,Limu Hu,Changjiang Wang,Xiao Tian,Xiang Zhang,Yi Hao,Bo Cheng,Jing Ma,Lei Wang,Jialin Liu,Ran Xie
Glycosylation plays a pivotal role in the intricate landscape of human cholangiocarcinoma (CCA), actively participating in key pathophysiological processes driving tumor progression. Among the various glycosylation modifications, O-linked β-N-acetyl-glucosamine modification (O-GlcNAcylation) emerges as a dynamic regulator influencing diverse tumor-associated biological activities. In this study, we employed a state-of-the-art chemical proteomic approach to analyze intact glycopeptides, unveiling the critical role of O-GlcNAcylation in orchestrating Keratin 18 (K18) and its interplay with tricarboxylic acid (TCA) cycle enzymes, specifically isocitrate dehydrogenases (IDHs), to propel CCA progression. Our findings shed light on the mechanistic intricacies of O-GlcNAcylation, revealing that site-specific modification of K18 on Ser 30 serves as a stabilizing factor, amplifying the expression of cell cycle checkpoints. This molecular event intricately fosters cell cycle progression and augments cellular growth in CCA. Notably, the interaction between O-GlcNAcylated K18 and IDHs orchestrates metabolic reprogramming by down-regulating citrate and isocitrate levels while elevating α-ketoglutarate (α-KG). These metabolic shifts further contribute to the overall tumorigenic potential of CCA. Our study thus expands the current understanding of protein O-GlcNAcylation and introduces a new layer of complexity to post-translational control over metabolism and tumorigenesis.
研究领域:
癌症生物学
·
分子生物学
·
生物化学
·
细胞生物学
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代谢学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2022
·Vol. 51
·期 12
·7009-7019
·
IF 2.047
Ma Xin,Ying Zhihua,Wen Fei,Li Lili,Zheng Xiaolong,Zheng Peng,Wang Gaofeng
Since cobalt-containing spinel oxides have good prospects for the detection of toxic gases, they also have great potential for applications in the field of gas sensors. However, ZnCo 2 O 4 -based gas sensors have the disadvantages of low response values and poor selectivity in formaldehyde detection. In this study, we attempted to prepare formaldehyde gas sensors by varying the addition of sodium citrate for hydrothermal synthesis of ZnCo 2 O 4 . During the fabrication process, it was found that an appropriate amount of sodium citrate content could produce ZnO on the surface of ZnCo 2 O 4 , and that the gas sensitivity of ZnO-ZnCo 2 O 4 to formaldehyde was better compared to that of pure ZnCo 2 O 4 . The sensor has a response rate of 17 at 20 ppm formaldehyde at 200°C. It also has good selectivity, repeatability, and stability. These results can provide foundational knowledge for the implementation of spinel oxide materials in the field of gas sensors.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
SOUTH AFRICAN JOURNAL OF BOTANY
·
2025
·
IF 2.7
Jingxin Chen,Jian Shi,Wenting Gu,Weiye Li,Ruiyin Lyu,Xueping Wu,Junming Wang,Chunhong Liu
Depression is a worldwide affliction that seriously compromises social adaptation and physical well-being. Citrus medica L. var. sarcodactylis Swingle (also known as Bergamot) is a citrus plant in the Rutanceae family. Bergamot essential oil, a naturally derived product, has been reported to possess neuroprotective effects. The present study aimed to reveal the neuroprotective mechanisms of bergamot essential oil in PC12 cells, and compare its efficacy with that of its predominant constituent, D-limonene. To confirm the target of action, this study sought to use PI3K inhibitor LY294002 to validate the mechanism in modulating autophagy and apoptosis of bergamot essential oil. By constructing a corticosterone-induced PC12 cell model of depression in vitro , we observed that bergamot essential oil stimulated the PI3K/AKT/mTOR signaling cascade, reducing autophagy markers LC3-II and p62 approximately by 22 % and 37 % respectively, and decreasing apoptosis rates by 37 %. Bergamot essential oil intervention also upregulated 5-HT levels and played a positive role in the BDNF/TrkB pathway which associated with synaptic plasticity. D-limonene (56.6 % of bergamot essential oil) was demonstrated to be a key contributor to these mechanisms. It exhibited protective effects comparable to bergamot essential oil against autophagy and BDNF/5-HT signaling activation, however, bergamot essential oil showed better efficacy in alleviating apoptosis. This study provides in vitro mechanistic evidence supporting the potential application of bergamot essential oil in the treatment of depression.
研究领域:
药理学
·
神经科学
·
植物学
·
细胞生物学
·
精神病学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2019
·
IF 4.507
Lingmei Yang,Shiyou Xing,Hongzhe Sun,Changlin Miao,Ming Li,Pengmei Lv,Zhongming Wang,Zhenhong Yuan
In this study, a series of Ni/SAPO-11 catalysts with different Ni loadings were prepared by citric acid-assisted impregnation for the hydroisomerization of oleic acid to iso-alkanes. Serving as a chelating ligand, citric acid first promoted the dispersion of Ni nanoparticles loaded on SAPO-11. Because of its acid properties, citric acid facilitated the removal of aluminium oxide species, contributing to the formation of a mesoporous SAPO-11 structure. A maximum of 67.3 mol% of iso-alkanes was formed using 7Ni/SAPO-11 as a catalyst under optimal conditions of 360 °C, 4 h, and 4.0 MPa H 2 . After reusing for five cycles, the catalyst still exhibited 21.5 mol% isomer selectivity. The reaction pathways and catalytic mechanisms concerning the oleic acid hydroisomerization process were proposed and discussed. The hydroisomerization of oleic acid mainly depended on the catalyst's Lewis acid sites, with the assistance of the metal centre and Brönsted acid sites. The mesoporous structure of SAPO-11 facilitated the availability of a significant number of catalytic Lewis acid sites, which, together with the highly dispersed Ni centres, contributed to the enhanced product isomerization.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2017
·
IF 1.591
Tengfei Bian,Xiujuan Zhang,Gaohong He,Zhijun Duan,Chunxu Dong,Xiangcun Li,Nana Guo
Hepatic encephalopathy (HE) is a neuropsychiatric disorder caused by chronic and acute liver diseases. It is believed that ammonia played an important role on the pathogenesis of the disease. Herein, acid-loaded water-in-oil-in-water (W1/O/W2) multiple emulsions with over 95% encapsulation efficiency were prepared and used to absorb colonic ammonia. The study of citric acid release from W1 to W2 in bulk deionized water indicated that only 17% acid released in 8 hours, which proved the stability of the multiple emulsions and hence prevented the intestine from being irritated by acid burst release. In vitro, the W1/O/W2 emulsion could remove around 90% ammonia in 1.5 hours from either the 3 mmol/L ammonia solution or the artificial colonic fluid with 1 and 0.5 mmol/L ammonia without acidifying the artificial colonic fluid. In vivo, compared with lactulose, W1/O/W2 emulsions could efficiently reduce the blood ammonia to the similar level in the rat models with HE without increasing the water content in feces. All these results indicated a potential application of W1/O/W2 multiple emulsions for the treatment of HE.
研究领域:
医学
·
药剂学
✓ 已验证
产品关联
DOI
高影响因子
Heliyon
·
2023
·
IF 4
Jie-Ru Hong,Ling Jin,Chen-Yu Zhang,Wen-Jing Zhong,Hui-Hui Yang,Guan-Ming Wang,Sheng-Chao Ma,Cha-Xiang Guan,Qing Li,Yong Zhou
Alveolar epithelial cell (AEC) senescence is implicated in the pathogenesis of pulmonary fibrosis (PF). However, the exact mechanism underlying AEC senescence during PF remains poorly understood. Here, we reported an unrecognized mechanism for AEC senescence during PF. We found that, in bleomycin (BLM)-induced PF mice, the expressions of isocitrate dehydrogenase 3α (Idh3α) and citrate carrier (CIC) were significantly down-regulated in the lungs, which could result in mitochondria citrate (citrate mt ) accumulation in our previous study. Notably, the down-regulation of Idh3α and CIC was related to senescence. The mice with AECs-specific Idh3α and CIC deficiency by adenoviral vector exhibited spontaneous PF and senescence in the lungs. In vitro , co-inhibition of Idh3α and CIC with shRNA or inhibitors triggered the senescence of AECs, indicating that accumulated citrate mt triggers AEC senescence. Mechanistically, citrate mt accumulation impaired the mitochondrial biogenesis of AECs. In addition, the senescence-associated secretory phenotype from senescent AECs induced by citrate mt accumulation activated the proliferation and transdifferentiation of NIH3T3 fibroblasts into myofibroblasts. In conclusion, we show that citrate mt accumulation would be a novel target for protection against PF that involves senescence.
研究领域:
肺科学
·
细胞生物学
·
分子生物学
·
病理学
✓ 已验证
DOI
PubMed
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 8
·1143
·
IF 4.034
Hai-Tao Ren,Jing Han,Ting-Ting Li,Qi Lin,Jia-Horng Lin,Ching-Wen Lou
The fate of arsenic in the water environment is of great concern. Here, the influences of oxalic acid and UV light illumination on the dissolution of naked ferrihydrite (Fhy), Fhy loaded with As(V) [Fhy*-As(V)], as well as the fate of As(V) at pH 3.0 were studied. With the assistance of oxalic acid, complexes of Fe(III)-oxalic acid produced on Fhy/Fhy*-As(V) were reduced to Fe(II)-oxalic acid by photo-induced electrons under UV light irradiation. UV light has nearly no impact on the release of As(V) in the system of Fhy*-As(V) without the assistance of oxalic acid. Nevertheless, in the existence of oxalic acid, UV light illumination resulted in the contents of liberated As(V) decreased by 775–1300% compared to that without light. Considering the coexistence of As(V), oxalic acid as well as iron oxides in aquatic environments, the present study revealed that UV illumination could enhance the retention of As(V) on Fhy in the acidic water environment containing oxalic acid.Keywords:ferrihydrite;As(V);photodissolution;oxalic acid;fate
研究领域:
环境科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
WATER RESEARCH
·
2016
·
IF 5.991
Peng Zhang,Weiyu Yao,Songhu Yuan
The release of arsenic (As) from the oxidation of As-rich pyrite is an important source of the high arsenic in groundwater. As a widespread low-molecular-weight organic acid , citrate plays an important role on the cycling of Fe(II)/Fe(III) through complexation in circumneutral subsurface environments, while the influence of citrate on the release of As from the oxidation of As-rich pyrite is poorly understood. In this study, As was loaded onto pyrite particles under anoxic conditions , and its release was investigated in the presence of 0–1 mM citrate at pH 7.4 under oxic conditions . As-loaded pyrite suspension was prepared by the equilibrium of 2.67 μM As(III) in 10 g/L pyrite under anoxic conditions with the decrease in dissolved As(III) concentration to 1 μM. The suspension was subsequently exposed to air for oxygenation. In the absence of citrate, the oxygenation decreased the partitioning of As in the solution because of the re-adsorption of aqueous As by the in situ generated Fe(III) oxyhydroxides. However, with the increase in citrate concentration from 0.1 to 1 mM, the As partitioned in the solution increased from 0.3 to 2.67 μM. In the presence of 1 mM citrate, the As(III) was almost completely oxidized to As(V) during the oxygenation. The mechanisms of citrate-enhanced release of As were mainly attributed to the ligand exchange of citrate with As for pyrite surface sites, the competitive adsorption of citrate with As on Fe(III) oxyhydroxides and pyrite, and the partitioning of As on the newly formed Fe(III) colloids. This finding presents an overlooked mechanism of the release of pyrite-associated As under oxic and circumneutral conditions.
研究领域:
环境科学
·
地球化学
✓ 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）