INDUSTRIAL CROPS AND PRODUCTS
·
2025
·
IF 6.2
Chengshun Liu,Jianlong Li,Miao Wang,Guotai Jian,Chen Zhu,Hanxiang Li,Yongxia Jia,Jinchi Tang,Lanting Zeng
Camellia sinensis var. assamica is a major variety used to produce black tea. However, the core compounds influencing its aroma quality are unknown. In this study, Yinghong No. 9 black tea (YJBT), a distinctive black tea in South China, was analyzed. We detected 44 aroma compounds and identified seven key contributors, namely linalool, geraniol, trans -linalool oxide (furanoid), hexanal, methyl jasmonate, phenylacetaldehyde, and β-ionone. Linalool, which was generally more abundant in spring tea than in summer tea, contributed significantly to sweet and floral aromas. ( R )-Linalool was the primary linalool form in Yinghong No. 9, wherein it was highly abundant in high-quality tea leaves. The substantial expression of a linalool synthase gene and the relatively high catalytic efficiency of the encoded enzyme likely contributed to the accumulation of ( R )-linalool. This study identified the primary aroma compounds in YJBT, providing a foundation for advancing our knowledge of the aromatic quality of black tea.
研究领域:
植物学
·
食品科学
·
分子生物学
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2024
·
IF 5.6
Xue Zhang,Yunsheng Shang,Qi Xie,Xingzhe Hu,Ke Wu,Lu-Lu Qu,Yingqiu Gu
Developing a Surface-enhanced Raman spectroscopy (SERS) method with excellent detecting ability, good recyclability and analyzing multiple pollutants rapidly are critical for evaluation of water quality in emergency pollution affairs. While constructing a multifunctional substrate with these characteristics to realize the application of SERS in water quality monitoring remains a challenge. In this work, a reusable Au@R–Fe 3 O 4 /g-C 3 N 4 SERS substrate is prepared by loading Au nanoparticles (Au NPs) on Fe 3 O 4 nanorings (R–Fe 3 O 4 ) and the formed Au@R–Fe 3 O 4 is further combined with g-C 3 N 4 nanosheets through a simple electrostatic assembly method. The Au@R–Fe 3 O 4 /g-C 3 N 4 nanocomposite presents multifunction of magnetic enrichment, SERS signal enhancement, multiple pollutants analyzing, and photocatalytic activity , which achieves quantitative detection of rhodamine B (RhB), tetracycline hydrochloride (TC), and 4-chlorophenol (4-CP), with detection limits of 5.30 × 10 −9 , 7.50 × 10 −8 , 7.69 × 10 −8 mol/L, respectively. Furthermore, the recyclable detection capability of Au@R–Fe 3 O 4 /g-C 3 N 4 for multi components is demonstrated by the strong SERS signal after 9 cycles of “detection-degradation” processes. Combined with good uniformity and stability, this SERS method based on Au@R–Fe 3 O 4 /g-C 3 N 4 substrate provides a new strategy for the multi-pollutants detection and degradation in water environment.
研究领域:
环境科学
·
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2020
·
IF 6.306
Yingqi Ruan,Yan Xu,Wenchi Zhang,Rongzhen Zhang
Maltogenic amylase suppressed starch retrogradation in baked products. Here, a maltogenic amylase-producing strain of bacteria was screened and identified as Bacillus licheniformis R-53. Its coding gene was cloned and over-expressed in Bacillus subtilis WB600. Recombinant maltogenic amylase BLMA exhibited activity of 3235 U/mg under optimal conditions (60 °C and pH 6.5), with a good thermostability and pH stability. Mixolab experiment showed that a concentration of 60 ppm BLMA significantly improved the operating characteristics of dough. Baking test indicated the recombinant BLMA reduced bread hardness by 2.12 times compared with the control. Compared with maltogenic amylase from Novozymes (Novamyl 3D BG) and Angel Yeast Co. Ltd. (MAM100), BLMA has better effect on improving the bread volume, and almost the same effect on reducing hardness, improving elasticity and maintaining sensory as Novamyl 3D BG. Adding BLMA improved bread quality, increased bread volume and decreased hardness during storage, thus extending its shelf life.
研究领域:
食品科学
·
微生物学
·
酶学
✓ 已验证
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2016
·Vol. 180
·期 2
·210-227
·
IF 1.606
Cao Yingying,Deng Dun,Sun Aijun,Zhang Yun,Hu Yunfeng
Chiral 2-chloropropanoic acids and their ester derivatives are crucial intermediates in the synthesis of many chemicals, especially herbicides. The enzymatic synthesis of chiral 2-chloropropanoic acids and their ester derivatives by esterases was not easily achieved, because the structural difference between the two enantiomers was too small to be recognized by esterases. Herein, we report the expression and functional characterization of one novel low temperature-resistant esterase EST12–7 identified from the genome of Pseudonocardia antitumoralis SCSIO 01299 isolated from the sediments of the South China Sea. Biocatalyst EST12–7 could hydrolyze racemic methyl 2-chloropropinate and generate optically pure ( R )-methyl 2-chloropropinate with high enantiomeric excess (>99 %) and conversion (>49 %) after process optimization. Notably, the addition of different surfactants and using surfactants of different concentrations in the kinetic resolution catalyzed by EST12–7 could greatly affect the enantiomeric excess and conversion rate of product ( R )-methyl 2-chloropropinate.
研究领域:
生物化学
·
酶工程
·
有机合成
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 21
·20575-20590
·
IF 2.8
Lu Pei,Yue Huifang,Xing Yi,Wei Jianjun,Zeng Zheng,Li Rui,Wu Wanrong
In this study, series of Ce x Zr y Mn z O 2 /r-Al 2 O 3 catalysts were prepared by impregnation method and explored to co-purification of NO x and Hg 0 at low temperature. The physical and chemical properties of the catalysts were investigated by XRD, BET, FTIR, NH 3 -TPD, H 2 -TPR, and XPS. The experimental results showed that 10% Ce 0.2 Zr 0.3 Mn 0.5 O 2 /r-Al 2 O 3 yielded higher conversion on co-purification of NO x and Hg 0 than the other prepared catalysts at low temperature, especially at 200–300 °C. 91% and 97% convert rate of NO x and Hg 0 were obtained, respectively, when 10% Ce 0.2 Zr 0.3 Mn 0.5 O 2 /r-Al 2 O 3 catalyst was used at 250 °C. Moreover, the presence of H 2 O slightly decreased the removal of NO x and Hg 0 owing to the competitive adsorption of H 2 O and Hg 0 . When SO 2 was added, the removal of Hg 0 first increased slightly and then presented a decrease due to the generation of SO 3 and (NH 4 ) 2 SO 4 . The results of NH 3 -TPD indicated that the strong acid of 10% Ce 0.2 Zr 0.3 Mn 0.5 O 2 /r-Al 2 O 3 improved its high-temperature activity. XPS and H 2 -TPR results showed there were high-valence Mn and Ce species in 10% Ce 0.2 Zr 0.3 Mn 0.5 O 2 /r-Al 2 O 3 , which could effectively promote the removal of NO x and Hg 0 . Therefore, the mechanisms of Hg 0 and NO x removal were proposed as Hg (ad) + [O] → HgO (ad), and 2NH 3 /NH 4 + (ad) + NO 2 (ad) + NO (g) → 2 N 2 + 3H 2 O/2H + , respectively.
ᅟ
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
MOLECULES
·
2019
·Vol. 24
·期 3
·420
·
IF 3.06
Bang-Jin Wang,Ai-Hong Duan,Jun-Hui Zhang,Sheng-Ming Xie,Qiu-E Cao,Li-Ming Yuan
Porous organic cages (POCs) have attracted extensive attention due to their unique structures and tremendous application potential in numerous areas. In this study, an enantioselective potentiometric sensor composed of a polyvinyl chloride (PVC) membrane electrode modified with CC3-R POC material was used for the recognition of enantiomers of 2-amino-1-butanol. After optimisation, the developed sensor exhibited enantioselectivity towardS-2-amino-1-butanol (logKS,RPot= −0.98) with acceptable sensitivity, and a near-Nernstian response of 25.8 ± 0.3 mV/decade within a pH range of 6.0–9.0.Keywords:enantioselective potentiometric sensor;2-amino-1-butanol;chiral porous organic cage;CC3-R;PVC membrane electrode
研究领域:
分析化学
·
材料科学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Oceanology and Limnology
·
2017
·Vol. 36
·期 2
·473-482
·
IF 0
Gong Yanhui,Ma Sanmei,Wang Yongfei,Xu Yongkai,Sun Aijun,Zhang Yun,Hu Yunfeng
A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC10 was characterized. At present, the reports about the kinetic resolution of racemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase EstC10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate ( R )-methyl 2-chloropropionate with high enantiomeric excess (>99%) after the optimization of process parameters such as pH, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration (80 mmol/L) of esterase EstC10 was higher than the kinetic resolution of another esterase, Est12-7 (50 mmol/L). The novel microbial esterase EstC10 identified from the deep sea was a promising green biocatalyst in the generation of ( R )-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.
研究领域:
生物化学
·
工业生物技术
✓ 已验证
DOI
Brazilian Journal of Pharmaceutical Sciences
·
2023
·
IF 1.3
Mei Xuejiao,Lu Dingqiang,Yan Xiangping
L-Malic acid is the Active Pharmaceutical Ingredient of the latest generation of compound electrolyte injection (STEROFUNDIN ISO, Germany) and plays a very important role in the rescue of critically ill patients. The optical purity of L-malic acid is a Critical Quality Attributes. A new reversed-phase high performance liquid chromatography (RP-HPLC) method for pre-column derivatization of D-malic acid enantiomer impurity in L-malic acid bulk drug was established. The derivatization reaction was carried out using (R)-1-(1-naphthyl)ethylamine ((R)-NEA) as a chiral derivatization reagent. The Kromasil C18 column was used with a detection wavelength of 225 nm, a flow rate of 1.0 mL·min-1, and a column temperature of 30 °C. The mobile phase was acetonitrile-0.01 mol·L-1 potassium dihydrogen phosphate solution (containing 20 mmol·L-1 sodium heptanesulfonate, adjusted to pH 2.80 with phosphoric acid) (at a ratio of 45:55) and the resolution of D-malic acid and L-malic acid derivatization products reached 1.7. The proposed method possesses the advantages of simple operation, mild conditions, stable derivatization products and low cost. Also it gave better separation and was more accurate than previous methods.
研究领域:
药物分析
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2020
·
IF 2.952
Yuan Lu,Hongqian Dai,Hanbing Shi,Lan Tang,Xingyuan Sun,Zhimin Ou
Fe 3 O 4 -Arg was selected as the optimal carrier due to its high activity recovery of immobilized cells in the preparation of Fe 3 O 4 -Arg-Cells. The optimal immobilization conditions for the preparation of Fe 3 O 4 -Arg-Cells were 30 °C, 4 h, pH 7, and 3 g dry yeast. The activity recovery of immobilized cells reached 76.8 %. For a batch reduction in a shaker in an alternating magnetic field, Fe 3 O 4 -Arg-Cells were used as a catalyst to gain ethyl ( R )-4-chloro-3-hydroxybutyrate (( R )-CHBE). For further improvement in reduction productivity, a continuous reduction in the magnetic fluidized bed reactor system (MFBRS) was completed. Under their optimal transformation conditions, it took 24 h for Fe 3 O 4 -Arg-Cells to complete the conversion of ethyl 4-chloro-3-oxobutanoate (COBE) (0.8553 mol/L) in the shaker and only 8 h for the batch reduction in an alternating magnetic field. Continuous reduction in MFBRS provided new ideas for the efficient production of ( R )-CHBE; 1.5882 mol/L (10 mL) of COBE can be completely converted in 6 h. The conversion and enantiomeric excess (e.e.) of ( R )-CHBE were 100 % and above 99.9 % respectively, in the three reaction systems mentioned above.
研究领域:
生物化学
·
合成生物学
·
纳米技术
✓ 已验证
DOI
高影响因子
NAUNYN-SCHMIEDEBERGS ARCHIVES OF PHARMACOLOGY
·
2019
·Vol. 393
·期 6
·967-978
·
IF 2.058
Rong Rong,Zhang Rui-zhen,Wang Xin,Dan Yu-han,Zhao Yun-li,Yu Zhi-guo
R -/ S -2-(2-hydroxypropanamido) benzoic acid ( R -/ S -HPABA), marine-derived anti-inflammatory antiplatelet drugs, were initially synthesised in our group. However, preliminary research showed that R -/ S -HPABA were eliminated rapidly because of extensive hydroxylation metabolism of phenyl ring in vivo. In order to reduce significant hydroxylation metabolism to improve pharmacological activity and bioavailability, trifluoromethyl group was incorporated into R -/ S -HPABA to synthesise R -/ S -2-(2-hydroxypropanamido)-5-trifluoromethyl benzoic acid ( R -/ S -HFBA), respectively. The purposes of this study were to report the synthesis of R -/ S -HFBA and compare the anti-inflammatory antiplatelet effect and pharmacokinetic properties of R -/ S -HFBA with those of R -/ S -HPABA. Carrageenan-induced rat paw edema assay was used for the evaluation of the anti-inflammatory activity. R -/ S -HFBA showed better results in inhibiting edema and were able to prolong the anti-inflammatory effect after carrageenan injection. The antiplatelet aggregation activity of R -/ S -HFBA and R -/ S -HPABA was studied on arachidonic acid-induced platelet aggregation of rabbit platelet-rich plasma. The aggregation inhibition rate of R- / S -HFBA was significantly ( p < 0.05) higher than that of R- / S -HPABA, respectively. Molecular docking study revealed that R -/ S -HFBA possess more potent binding affinity with COX-1/COX-2 than R -/ S -HPABA, respectively, and that the presence of trifluoromethyl group leads to increase in activity of R -/ S -HFBA. R -/ S -HFBA also afford more favorable pharmacokinetic properties than R- / S -HPABA, respectively, such as higher C max , larger AUC 0-∞ , and longer t 1/2 , which, as expected, are more metabolically stable.
研究领域:
药理学
·
药物化学
·
药物设计
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2024
·
IF 5.7
Xiaogan Zhao,Tao Lin,Wenkai Jiang,Yihan Lin,Luyao Xiao,Yufang Tian,Kai Ma,Changliang Zhang,Feng Ji,Ghahvechi Chaeipeima Mahsa,Xin Rui,Wei Li
Lactobacillus helveticus LZ-R-5 (R-5), a strain with high epithelial adhesion and bioactive exopolysaccharide production, was isolated from Tibetan kefir grains. This study investigated its potential to alleviate intestinal inflammation using a DSS-induced colitis model in BALB/c mice. We integrated microbial diversity and serological analyses to assess changes in gut flora and cytokines following the R-5 treatment. Pathological assessments showed that R-5 reduced crypt distortion in the proximal colon and mitigated hepatic immune challenges by enhancing gut barrier function. The increased relative expression of TGF-β1 and the downregulation of NLRP3-related inflammatory factors were conducive to preventing organ damage in the thymus and spleen of mice with colitis. Additionally, R-5 stimulated GPR43 expression and improved epithelial nutrition, promoting mucin production to prevent enterotoxin leakage. It also modulated the gut microbiota by suppressing Bacteroides and Erysipelatoclostridium, leading to a microbiota composition more akin to that of normal flora.
研究领域:
微生物学
·
免疫学
·
消化系统疾病
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF BIOTECHNOLOGY
·
2018
·
IF 2.533
Jiapao Wang,Pengfei Cheng,Yifeng Wu,Anming Wang,Fangming Liu,Xiaolin Pei
( R )-Pantolactone (PL) is a key chiral intermediate for the synthesis of calcium ( R )-pantothenate and ( R )-panthenol used as food additives. The commercial production of ( R )-pantothenate is performed by the resolution of racemic pantothenate, which is synthesized through an aldol condensation and a cyanation reaction. In this study, we investigated another synthetic method of ( R )-pantothenate through the stereoselective reduction of ketopantoyl lactone (KPL) by aldo-keto reductase (AKR). A series of conjugated polyketone reductases (CPRs) were discovered from GenBank database by genome mining approach. The putative CPR gene from Candida orthopsilosis Co 90–125 ( Cor CPR) was cloned and functionally expressed in Escherichia coli BL21 (DE3). The optimum pH and temperature of recombinant Cor CPR were 6.0–7.0 and 40 ℃, respectively. The K m and v max toward KPL were1.3 mM and 227.3 μ mol/min/mg protein, respectively. The conserved sequences suggest that Cor CPR belongs to AKR3C family of AKR superfamily. Furthermore, a catalytic tetrad was proposed, and the detailed mechanism was clarified by molecular docking. In a batch reaction, 50 mM KPL was reduced to ( R )-PL with 99% conversion and > 99% enantiomeric excess within 5 h. The recombinant Cor CPR from C. orthopsilosis shows potential application in the asymmetric synthesis of ( R )-pantothenate preparation.
研究领域:
生物化学
·
分子生物学
·
工业微生物学
✓ 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）