Food Analytical Methods
·
2018
·Vol. 12
·期 2
·431-439
·
IF 2.245
Wang Ping,Chen Yisheng,Xu Xueming,Hellmann Bernhard,Huang Caihong,Bai Yuxiang,Jin Zhengyu
This paper proposes a facile and specific method tailored for quantifying and confirming folic acid in food, based on the combination of high-performance thin layer chromatography with fluorescence densitometry and surface-enhanced Raman spectroscopy. Chromatography was carried out on silica gel plates, using methanol/ethyl acetate/ammonia (6:4:1, v / v / v ) as the mobile phase. For the first time, ozone gas was utilized as the derivative agent, which efficiently induced the appearance of strong fluorescence of the analyte. Thereafter, fluorescent densitometry measurements were carried out for quantitative purpose, offering good linearity ( R 2 > 0.999) and sensitivity (0.7–1.4 mg/kg). In addition, the applicability and reliability of the established method was validated with food and food supplement samples, showing good agreement with the data obtained by conventional HPLC-UV as the benchmark, but with remarkably higher efficiency. Apart from that, the in situ-obtained surface-enhanced Raman spectroscopic fingerprint of bands under optimized conditions (532-nm incident laser and tenfold concentrated silver nanoparticles) enabled unambiguous identification of the targeted compound, serving as a convenient and affordable tool to prevent potential mistake from false-positive results.
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JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Xingcheng Ma,Kun Qi,Shuting Wei,Lei Zhang,Xiaoqiang Cui
Efficient and low-cost oxygen evolution reaction (OER) electrocatalysts for water-splitting are highly desired. This article reports an in situ synthesis of metal-organic framework (MOF) encapsulated bimetallic nanoparticles by etching nickel-copper alloy nanoparticles without additional metal precursors. The nickel-copper nanoparticles serve as the metal precursor sources and are encapsulated into metal-organic frameworks to enhance the catalytic performances and stability for OER. The catalyst shows excellent OER performance, superior to the copper-nickel nanoparticles and pure MOF-74. This work also provides a promising way to extend the application of MOFs for novel catalysts.
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PHARMACEUTICAL BIOLOGY
·
2018
·
IF 1.918
Wenlong Yang,Guanlin Zhou,Shubing Zou,Wentao Yang,Aihong Liu,Shuilin Sun,Baogang Xie
Context: d-Glucaro-1,4-lactone (1,4-GL) exists in many vegetables and fruits. Metabonomics has not been used to investigate the role of 1,4-GL in preventing liver cancer.Objective: The pharmacological effects and metabolite alterations of 1,4-GL on the prevention of diethylnitrosamine (DEN)-induced liver cancer were investigated.Materials and methods: Ten healthy Sprague–Dawley rats served as control and 46 were used to establish rat liver cancer model. 1HNMR-based metabonomics was used to compare the effects of oral 1,4-GL (50 mg/kg) in liver cancer rats (n = 26) after 10 consecutive weeks of intervention. The amino acids in rat serum were quantified by HPLC-UV, and the changes in Fischer’s ratio were calculated.Results: The 20-week survival rate of DEN-induced liver cancer rats administered with oral 1,4-GL was increased from 45.0 to 70.0% with reduced carcinogenesis of the liver and significantly lowered serum α-fetoprotein level (14.28 ± 2.89 ng/mL vs. 18.56 ± 4.65 ng/mL, p = 0.012). The serum levels of leucine, valine, 3-hydroxybutyrate, lactate, acetate and glutamine in the DEN + 1,4-GL group returned to normal levels compared with those of the DEN group on week 20. Fischer’s ratio in the rat serum of DEN group was 1.62 ± 0.21, which was significantly lower than that in healthy rats (2.3 ± 0.12). However, Fischer’s ratio increased to 1.89 ± 0.22 in the DEN + 1,4-GL group.Discussion and conclusions: 1,4-GL exerted positive effects on liver carcinogenesis in rats by pathological examination and metabonomic analysis. Its mechanism may be related to the restoration of amino acid and energy metabolism.
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JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 29
·期 24
·20603-20606
·
IF 2.324
Hao Yueyue,Zhang Nan,Luo Jing,Liu Xiaoya
Water-dispersible copper nanoparticles (Cu NPs) with good antioxidation properties are facilely synthesized in aqueous solution without inert gas protection employing tannic acid (TA) as the stabilizer and protectant. The sizes of as-prepared tannic acid capped copper nanoparticles (TA-Cu NPs) are in the range of 20–40 nm with a narrow size distribution. Owing to the protection of TA layer, TA-Cu NPs exhibit excellent anti-oxidation power and no oxidation was observed even after being stored under ambient conditions for 90 days. In addition, homogenous Cu NPs inks could be synthesized via the simple dispersion of TA-Cu NPs in water, which can be inkjet-printed onto flexible substrates into conductive patterns using a common color printer.
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PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY
·
2019
·
IF 2.87
Bojun Yan,Yuhua Zhang,Jun Li,Jiapeng Fang,Tingting Liu,Liyao Dong
Cytochrome P450s (P450s) confer resistance against herbicides, and this is increasingly becoming a concern for weed control. As a widespread Gramineae weed in paddy fields , Echinocloa glabrescens has become resistant to the acetolactate synthase (ALS)-inhibiting triazolopyrimidine herbicide penoxsulam. In this study, we found that the GR 50 of the resistant population (SHQP-R) decreased substantially from 25.6 to 5.0 and 6.2 g a.i. ha −1 after treatment with the P450 inhibitors piperonyl butoxide (PBO) and malathion , respectively. However, P450 inhibitors almost had no effects on the susceptibility of the sensitive population (JYJD-S) to penoxsulam. To investigate the mechanisms of metabolic resistance, transcriptome sequencing analysis was performed to find candidate genes that may confer resistance to penoxsulam in E. glabrescens . A total of 233 P450 differentially expressed genes (DEGs) were identified by transcriptome sequencing. We found that the metabolic process and metabolic pathways were the most highly enriched in DEGs. Further, twenty-seven candidate P450 DEGs were selected for qPCR validation analyses. After penoxsulam treatment, the relative expression levels were significantly higher in SHQP-R than in JYJD-S. Among these, the relative expression of twenty-three P450 DEGs (eighteen from the CYP72A-71C-74A-96A-734A subfamily; five from CYP81E1-94C1–94B3-714C1-714C2) were upregulated and four P450 DEGs (from CYP724B1-711A1-707A7-97B2) were downregulated. Changes in the expression of these candidate P450 genes in E. glabrescens were in response to penoxsulam, which provides preliminary evidence for the role of P450s in herbicide metabolism in E. glabrescens. However, further functional studies on metabolic resistance to penoxsulam in a resistant E. glabrescens population are required.
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Applied Sciences-Basel
·
2018
·Vol. 8
·期 12
·2530
·
IF 1.689
Nan Fang Nie,Xin Xing Zhang,Chu Shan Fang,Qiu Yan Zhu,Jiao Yang Lu,Fu Rui Zhang,Qing Feng Yao,Wei Tao Huang,Xue Zhi Ding,Li Qiu Xia
Game theory—the scientific study of interactive, rational decision making—describes the interaction of two or more players from macroscopic organisms to microscopic cellular and subcellular levels. Life based on molecules is the highest and most complex expression of molecular interactions. However, using simple molecules to expand game theory for molecular decision-making remains challenging. Herein, we demonstrate a proof-of-concept molecular game-theoretical system (molecular prisoner’s dilemma) that relies on formation of the thymine–Hg2+–thymine hairpin structure specifically induced by Hg2+and fluorescence quenching and molecular adsorption capacities of cobalt oxyhydroxide (CoOOH) nanosheets, resulting in fluorescence intensity and distribution change of polythymine oligonucleotide 33-repeat thymines (T33). The “bait” molecule, T33, interacted with two molecular players, CoOOH and Hg2+, in different states (absence = silence and presence = betrayal), regarded as strategies. We created conflicts (sharing or self-interest) of fluorescence distribution of T33, quantifiable in a 2 × 2 payoff matrix. In addition, the molecular game-theoretical-system based on T33 and CoOOH was used for sensing Hg2+over the range of 20 to 600 nM with the detection limit of 7.94 nM (3σ) and for determination of Hg2+in pond water. Inspired by the proof-of-concept for molecular game theory, various molecular decision-making systems could be developed, which would help promote molecular information processing and generating novel molecular intelligent decision systems for environmental monitoring and molecular diagnosis and therapy.Keywords:cobalt oxyhydroxide nanosheets;fluorescent sensing;game theory;Hg2+;thymine–Hg2+–thymine
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PHARMAZIE
·
2014
·Vol. 69
·期 12
·898-903
·
IF 1.003
Xia Meng-Ming,Wang Li,Pan Pei-Pei,Wang Hai-Yun,Chen Meng-Chun,Chen Yi,Dai Da-Peng,Cai Jian-Ping,Hu Guo-Xin
CYP2C9 is one of four known members of the human cytochrome P450 CYP2C superfamily, with at least 57 CYP2C9 alleles being previously identified. Genetic polymorphisms of CYP2C9 significantly influence the efficacy and safety of some drugs, which might cause adverse effects and therapeutic
failure. The purpose of the present study was to clarify the role of 36 CYP2C9 alleles, 21 novel alleles (*36-*56) found in the Chinese population, in the oxidative metabolism of diclofenac in vitro. Insect microsomes expressing the 36 human CYP2C9 alleles were incubated with 2-100
μM diclofenac for 30 min at 37°C and terminated by the addition of 30 μL 0.1 M HCl. Diclofenac and 4'-hydroxyl (OH)-diclofenac, the major diclofenac metabolite, were analyzed by high-performance liquid chromatography (HPLC). Compared with wild-type CYP2C9*1, most variants
showed significantly altered values in Vmax, Km and intrinsic clearance (Vmax/Km). Only one variant exhibited markedly increased intrinsic clearance value, whereas 31 variants exhibited significantly decreased values. Thus, this study demonstrated
that more attention should be given to subjects carrying these CYP2C9 alleles when administering diclofena.
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Artificial Cells Nanomedicine and Biotechnology
·
2014
·
IF 0
Meihao Liang,Xiaoliang Zheng,Linglan Tu,Zhen Ma,Zunyuan Wang,Dongmei Yan,Zhengrong Shen
In order to study the liver targeting of the N-galactosylated chitosan (GC) polymer in liver, we first conjugated the lactobionic acid with chitosan (CS) to obtain the carrier of GC with different degree of substitution of lactosyl group. Western blot was performed to detect the expression levels of the asialoglycoprotein receptors (ASGPR) in the cell lines of HepG2, SMMC-7721, and HL-7702. The protein level of ASGPR was lower in HepG2 compared to HL-7702 and SMMC-7721. Although all treated by CS, viabilities of HL-7702 and HepG2 did not experience any significant drop, while viability of SMMC-7721 decreased 15% on average from control. It was the first data about the inhibitory effect of GC on the liver cells. Fluorescein isothiocyanate (FITC) labeled GC (GC-FITC) was injected intravenously into mice at a dose of 0.02 μmol/mouse. GC-FITC showed maximum liver localization at 5 min and even detectable at 48 h after injection. Further, the accumulation of GC in liver was about 5.4-fold higher than that of CS. In conclusion, GC demonstrated its higher efficacy in drug liver targeting and thus could be a more promising drug or gene carrier in future therapies.
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JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2014
·
IF 3.107
Guang Yang,Tan Yang,Wendian Zhang,Miao Lu,Xiang Ma,Guangya Xiang
The antitumor efficacy of ursolic acid (UA) was limited by poor hydrophilicity and low bioavailability. To overcome this issue, UA was encapsulated in liposomes modified with folate conjugates for better solubility and bioavailability. This novel agent was prepared by a thin-film dispersion method and characterized by mean diameter, zeta potential, and entrapment efficiency (160.1 nm, −21.2 mV, and 88.9%, respectively). In vitro, cellular uptake efficiency, cytotoxicity, apoptosis, and cell cycle analyses were performed to show that folate-receptor (FR) positive cells endocytose more FR-targeted liposome (FTL-UA) than nontargeted PEGylated liposome (PL-UA) and that FTL-UA induced more cytotoxicity and higher apoptosis than PL-UA. Pharmacokinetic assessments showed advantages of systemic bioavailability of FTL-UA (AUC = 218.32 mg/L·h, t1/2 = 7.61 h) over free UA (AUC = 36.88 mg/L·h, t1/2 = 0.78 h). In vivo, FTL-UA showed significantly higher human epidermoid carcinoma (KB) inhibition in Balb/c nu/nu mice compared to PL-UA or free UA. The results indicate the great potential of FTL-UA against KB tumor.
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RSC Advances
·
2015
·Vol. 5
·期 47
·37697-37702
·
IF 3.84
Liuyi Yin,Yufeng Hu,Xianming Zhang,Jianguang Qi,Weiting Ma
Batch reaction experiments were performed to investigate the salt effect on the yield of trioxane in the reaction solution. The salts considered include NaHSO4, Na2SO4, NaH2PO4, Na2HPO4, KCl, NaCl, LiCl, ZnCl2, MgCl2, and FeCl3. The effects of the anionic structure and the cation charge density on the yield of trioxane in the reaction solution were elucidated and the mechanisms that govern such effects were established. It is shown that the first four salts exerted a negative effect on the yield of trioxane in the reaction solution and such an effect increased progressively from left to right. This trend is due to the formation of NaHSO4, H3PO4, or (H3PO4 and NaH2PO4), which decreased the concentration of H+ in the solution. The latter six salts showed a positive effect on the yield of trioxane in the reaction solution. The salt effect paralleled the ability of the salt to decrease the water activity of the reaction solution and followed the order KCl < NaCl < LiCl < ZnCl2 < MgCl2 < FeCl3. Continuous production experiments were performed to investigate the salt effect on the concentration of trioxane in the distillate. The salts considered were KCl, NaCl, LiCl, ZnCl2, MgCl2, and FeCl3, and the salt effect increased progressively from left to right. Such an effect was shown to be determined by the ability of the salt to increase the yield of trioxane in the reaction solution and to increase the relative volatilities of trioxane and water and of trioxane and oligomers.
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FLUID PHASE EQUILIBRIA
·
2014
·
IF 2.241
Ye Yuan,Yixin Leng,Hui Shao,Chunxiang Huang,Kai Shan
The solubility of dl -malic acid in water, ethanol and ethanol + water mixtures was investigated by a static analytical technique using the acid–base titration method at temperatures ranging from 298.15 to 333.15 K. The experimental results indicated that the solubility of dl -malic acid in the binary solvent mixtures increases with increasing temperature and decreases with increasing mass fraction of ethanol. The measured solid–liquid equilibrium (SLE) data were correlated by the modified Apelblat, λh and van’t Hoff equations. The calculated solubility demonstrated good agreement with the experimental data. It was found that the modified Apelblat equation could give the best correlation results, and subsequently used to derive the standard enthalpy, entropy and Gibbs energy change of solution of dl -malic acid in ethanol + water binary mixtures.
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PHOTOCHEMISTRY AND PHOTOBIOLOGY
·
2014
·Vol. 90
·期 5
·1144-1149
·
IF 2.684
Zhi Li,Li-Li Pan,Fei-Long Zhang,Xia-Li Zhu,Yang Liu,Zhen-Zhong Zhang
This report explores some properties of 80–200 nm nanoparticles containing 5-aminolevulinic acid (ALA) and fullerene (C60) for photodynamic therapy (PDT). Compared with ALA, the nanoparticles yielded more protoporphyrin IX (PpIX) formation in cells and tissues and to a significant improvement in antitumor efficacy in tumor-bearing mice. Maximum levels of PpIX were obtained 4 h after administration and selective PpIX formation in tumor was observed. These nanoparticles appear to be a useful vehicle for drug delivery purposes. In this study, a procedure for preparing fullerene nanoparticles containing ALA was developed. The product alone exhibited no detectable toxicity in the dark and was superior to ALA alone in promoting PpIX biosynthesis and PDT efficacy both in culture and in a murine tumor model. These results suggest that this procedure could be the basis for an improved PDT protocol for cancer control.
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