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2.
Ultrason Sonochem ; 105: 106872, 2024 May.
Article in English | MEDLINE | ID: mdl-38599128

ABSTRACT

The present study aimed to investigate the potential of ultrasonic treatment during fermentation for enhancing the quality of fortified wines with varying time and power settings. Chemical analysis and sensory evaluation were conducted to assess the impact of ultrasonic treatment on wine quality. Results showed that ultrasonic treatment could increase total anthocyanin and total phenol content, reduce anthocyanin degradation rate, and improve color stability. Moreover, ethyl carbamate content was lower in the ultrasonic group after aging compared to non-ultrasonic group. A combination of 200 W for 20 min resulted in higher sensory scores and more coordinated taste, while a combination of 400 W for 40 min produced higher levels of volatile compounds (21860.12 µg/L) leading to a richer and more elegant aroma. Therefore, ultrasound can be used as a potential technology to improve the quality of wine.


Subject(s)
Anthocyanins , Fermentation , Wine , Wine/analysis , Anthocyanins/analysis , Taste , Food Quality , Ultrasonic Waves , Color , Food, Fortified/analysis , Phenols/analysis
3.
Front Bioeng Biotechnol ; 12: 1355004, 2024.
Article in English | MEDLINE | ID: mdl-38292827

ABSTRACT

The development of non-antibiotic strategies for bacterial disinfection is of great clinical importance. Among recently developed different antimicrobial strategies, nanomaterial-mediated approaches, especially the photothermal way and reactive oxygen species (ROS)-generating method, show many significant advantages. Although promising, the clinical application of nanomaterials is still limited, owing to the potential biosafety issues. Further improvement of the antimicrobial activity to reduce the usage, and thus reduce the potential risk, is an important way to increase the clinical applicability of antibacterial nanomaterials. In this paper, an antimicrobial nanostructure with both an excellent photothermal effect and peroxidase-like activity was constructed to achieve efficient synergistic antimicrobial activity. The obtained nano-antimicrobial agent (ZIF-8@PDA@Pt) can not only efficiently catalyze the production of ROS from H2O2 to cause damage to bacteria but also convert the photon energy of near-infrared light into thermal energy to kill bacteria, and the two synergistic effects induced in a highly efficient antimicrobial activity. This study not only offers a new nanomaterial with efficient antibacterial activity but also proposes a new idea for constructing synergistic antibacterial properties.

4.
Sci Total Environ ; 867: 161539, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-36642268

ABSTRACT

Emerging contaminants, such as neonicotinoid pesticide acetamiprid (Ace), are frequently detected in the water environment, which can interact with existing heavy metal cadmium (Cd) to produce unpredicted influence. Limited studies have evaluated the effects of multiple pollutant exposures on aquatic animals. Here, we characterized the joint toxicity of Ace and Cd exposure to zebrafish (Danio rerio). The results revealed that Cd and its combined exposure with Ace had an inhibitory effect on the growth of larval zebrafish and induced morphological defects. Combined exposure to high doses of Ace and Cd could significantly reduce the levels of TG, glucose, and pyruvate in larval zebrafish. Untargeted metabolomics revealed that Cd treatment (285) produced more differentially expressed metabolites (DEMs) than Ace treatment (115), and combined treatment produced the most DEMs (294). The KEGG pathway enrichment analysis showed that they could disrupt riboflavin metabolism, amino acid metabolism, and glycolipid metabolism in the larvae of D. rerio. ELISA showed that VB2, FMN, and FAD levels were significantly increased. In addition, gene expression analysis exhibited that the mRNA levels of essential genes related to glycolipid metabolism were substantially affected, such as PK, PEPckc, PPAR-α, and FABP6. Furthermore, targeted amino acid metabolomics confirmed that both single exposure to Cd and combined exposure to Ace and Cd altered the levels of amino acids in larvae, including ALA, ARG, MET, PRO, TYR, VAL, GLY, ORN, and PHE. Taken together, exposure to Ace and Cd, alone or in combination, exerted harmful effects on the individual development, riboflavin metabolism, glycolipid metabolism, and amino acid metabolism disorder of D. rerio. These findings highlighted that more attention should be paid to the compound toxicity of chemical mixtures to aquatic organisms.


Subject(s)
Water Pollutants, Chemical , Zebrafish , Animals , Zebrafish/metabolism , Cadmium/metabolism , Larva , Neonicotinoids/toxicity , Neonicotinoids/metabolism , Amino Acids/metabolism , Glycolipids/metabolism , Riboflavin , Water Pollutants, Chemical/metabolism
5.
Foods ; 13(1)2023 Dec 21.
Article in English | MEDLINE | ID: mdl-38201058

ABSTRACT

Zizania latifolia (Z. latifolia) is a popular aquatic vegetable with various nutrients in south China, but little is known about its cultivars and growing seasons in terms of the nutritional components. This work aims to characterize the nutrients of five Z. latifolia cultivars in different growing seasons. The results showed that Z. latifolia samples differed in terms of chemical parameters, which were significantly affected by variety, growing season, and their interaction. Zhejiao No. 8, harvested in the autumn, stood out with the highest levels of vitamin C. Tangxiajiao and Zhejiao No. 1 contained the highest values of total soluble solids, reducing sugar, soluble proteins, and amino acids. Significant differences were observed between the autumn Z. latifolia and spring samples; the former were of higher quality than the latter based on hierarchical clustering analysis and principal component analysis. Moreover, total amino acids (TAA) and glutamic acid (GLU) were selected as the key indicators for Z. latifolia comprehensive quality by multiple linear regression analysis. This study provides essential information on Z. latifolia quality characteristics corresponding to cultivars and growing seasons, which lays the foundation for promoting the quality improvement of Z. latifolia scientifically.

6.
Foods ; 11(23)2022 Nov 27.
Article in English | MEDLINE | ID: mdl-36496634

ABSTRACT

As an ingredient in various foods, Chrysanthemum morifolium flower is popular due to its multiple health benefits. Pyrrolizidine alkaloids (PAs) are hepatotoxic secondary metabolites in Chrysanthemum family. Effects of high-pressure extraction (HPE) on PAs removal efficiency, as well as the retention efficiency of functional components, including chlorogenic acid, luteolin-7-ß-D-glucopyranoside, 3,5-dicaffeyl quinic acid and total flavonoids, were investigated and optimized using response surface methodology (RSM). Pressure (0.1-200 MPa), numbers of cycles (1-5) and acetic acid concentration (0-10%) were chosen as the independent variables. The results indicated that the pressure was the most significant factors affecting all responses. The optimum HPE for removing Pas and retaining functional components were set at 124 MPa, with one cycle and with an acetic acid concentration of 10%. After comparing the experimental optimum values and predicted optimum values, the validity of RSM model was proved.

7.
Chem Biol Interact ; 366: 110150, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-36084721

ABSTRACT

Aquatic organisms are often exposed to contaminants that occur in the natural environment. Nevertheless, the toxic effects of chemical combinations on aquatic animals and their underlying toxic mechanisms for dealing with such exposures are still not fully understood. In this study, we investigated the combined effects of cadmium (Cd) and acetamiprid (ACE) on zebrafish (Danio rerio) using various endpoints. Cd exhibited a 96-h LC50 value of 4.77 mg a.i. L-1 against zebrafish embryos, which was lower than that of ACE (152.6 mg a.i. L-1). In contrast, the 96-h LC50 value of the mixture of Cd and ACE was 157.4 mg a.i. L-1. The mixture of Cd and ACE had a synergetic effect on the organisms. The activities of T-SOD, POD, and CarE were significantly changed in most exposures compared with the control group. In addition, five genes (TRα, crh, Tnf, IL, and P53) involved in oxidative stress, cellular apoptosis, the immune system, and the endocrine system exhibited more remarkable changes when exposed to chemical mixtures relative to their individual counterparts, demonstrating variations in the cellular and mRNA expression levels induced by the mixture exposure of ACE and Cd during the embryonic development of zebrafish. Therefore, these results indicated that the combined pollution of ACE and Cd could be a potentially hazardous factor, and further investigation is necessary for the safety evaluation and application of ACE. Moreover, further investigation on the combined toxicities of various chemicals must be performed to determine the chemical mixtures with synergistic responses.


Subject(s)
Water Pollutants, Chemical , Zebrafish , Animals , Cadmium/toxicity , Embryo, Nonmammalian , Larva , Neonicotinoids , Oxidative Stress , RNA, Messenger/metabolism , Superoxide Dismutase/metabolism , Tumor Suppressor Protein p53/metabolism , Water Pollutants, Chemical/toxicity
8.
Sci Rep ; 12(1): 15667, 2022 09 19.
Article in English | MEDLINE | ID: mdl-36123341

ABSTRACT

Brown rice (BR) contains more lipids, as compared with white rice, but its indigestibility and rancidity limit the consumer acceptability. Therefore, the objective of this study was to compare the effect of high-pressure (HP), freeze-thaw cycles (FTC) and germination-parboiling (GP) treatments on lipid in vitro digestibility and rancidity of BR. GP treated BR released the most fatty acids (especially palmitic acid and stearic acid) after in vitro digestion, followed by FTC treated BR. FTC treated BR kept the highest value of fat acidity during storage, while opposite results were observed in GP treated BR. Although HP treatment increased fat acidity value immediately, it slowed down the increase of fat acidity with storage. The results of conjugated dienes and malonaldehydes content in BR stored under accelerated conditions indicated better lipid oxidation stability after HP and GP treatment, and that it's necessary for FTC treated BR products to be stored under anaerobic conditions.


Subject(s)
Oryza , Fatty Acids , Freezing , Palmitic Acid , Stearic Acids
9.
Sci Rep ; 12(1): 16045, 2022 09 26.
Article in English | MEDLINE | ID: mdl-36163367

ABSTRACT

Different pollutants usually co-exist in the natural environment, and the ecological and health risk assessment of agrochemicals needs to be carried out based on the combined toxicological effects of pollutants. To examine the combined toxicity to aquatic organisms, the effects of cadmium (Cd) and five pesticides (acetamiprid, carbendazim, azoxystrobin, chlorpyrifos, and bifenthrin) mixture on zebrafish (Danio rerio) larvae were assessed. The data from the 96-h toxicity test indicated that bifenthrin possessed the highest toxicity to D. rerio with the LC50 value of 0.15 mg L-1, followed by chlorpyrifos (0.36 mg L-1) and azoxystrobin (0.63 mg L-1). Cd (6.84 mg L-1) and carbendazim (8.53 mg L-1) induced the intermediate toxic responses, while acetamiprid (58.39 mg L-1) presented the lowest toxicity to the organisms. Pesticide mixtures containing chlorpyrifos and bifenthrin or acetamiprid and carbendazim showed synergistic impacts on the zebrafish. Besides, two binary combinations of Cd-acetamiprid and Cd-chlorpyrifos also displayed a synergistic effect on D. rerio. Our results offered a better idea of the mixed ecological risk assessment of Cd and different agricultural chemicals to aquatic organisms. Our findings better interpreted how the interaction between Cd and various agrochemicals changed their toxicity to aquatic vertebrates and provided valuable insights into critical impacts on the ecological hazard of their combinations.


Subject(s)
Chlorpyrifos , Environmental Pollutants , Pesticides , Water Pollutants, Chemical , Agrochemicals/toxicity , Animals , Benzimidazoles , Cadmium/toxicity , Carbamates , Chlorpyrifos/toxicity , Environmental Pollutants/pharmacology , Larva , Pesticides/toxicity , Pyrethrins , Pyrimidines , Strobilurins , Water Pollutants, Chemical/toxicity , Zebrafish
10.
Foods ; 11(7)2022 Apr 02.
Article in English | MEDLINE | ID: mdl-35407123

ABSTRACT

Kelp (Laminaria japonica) is a popular and nutritious sea vegetable, but it has a strong biosorption capacity for heavy metals. The high content of cadmium (Cd) and lead (Pb) is a threat to the quality of kelp. The objective of this study was to investigate the effects of high-pressure-assisted extraction (HPAE) conditions on Cd and Pb removal efficiency from kelp. Pressure intensity (0.1-200 MPa), the number of HPAE cycles (one to five) and acetic acid concentration (0-10%) were optimized using response surface methodology. The pressure intensity had the most significant positive effects on Cd and Pb removal efficiency, while the correlation between acetic acid concentration and removal efficiency was positive for Cd and negative for Pb. The optimum conditions for the removal of Cd and Pb were attained at 188 MPa, with four cycles and with an acetic acid concentration of 0%. At optimum conditions, the experimental values of removal efficiency were 61.14% (Cd) and 70.97% (Pb), and this was consistent with the predicted value, confirming the validity of the predictive model.

11.
J Hazard Mater ; 423(Pt A): 126962, 2022 02 05.
Article in English | MEDLINE | ID: mdl-34464866

ABSTRACT

Colorimetric and fluorescent methods for Ochratoxin A (OTA) detection are convenient and well received. However, the pigments and autofluorescence originated from food matrices often interfere with detection signals. We have developed a strategy with colorimetric and fluorescent dual modes to solve this challenge. In the colorimetric mode, OTA aptamer (AP9) was assembled into a DNA triple-helix switch with a specially designed signal-amplifying sequence. The OTA-induced G-quadruplex (G4) of AP9 would open the switch and release the signal-amplifying sequence for colorimetric signal amplification. The G4 structures of AP9 were further utilized to combine with the fluorogenic dye ThT for fluorescent mode. By skillfully engineering DNA G4 assembly for signal amplification, there was no need for any DNA amplification or nanomaterials labeling. Detections could be carried out in a wide temperature range (22-37 â„ƒ) and finished rapidly (colorimetric mode, 60 min; fluorescent mode, 15 min). Broad linear ranges (colorimetric mode, 10-1.5 ×103 µg/kg; fluorescent mode, 0.05-1.0 ×103 µg/kg) were achieved. The limit of detection for colorimetric and fluorescent modes were 4 µg/kg and 0.01 µg/kg, respectively. The two modes have been successfully applied to detect OTA in samples with intrinsic pigments and autofluorescence, showing their applicability and reliability.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Colorimetry , DNA , Limit of Detection , Ochratoxins , Reproducibility of Results
12.
RSC Adv ; 10(38): 22449-22453, 2020 Jun 10.
Article in English | MEDLINE | ID: mdl-35514543

ABSTRACT

This communication describes the palladium-catalyzed reductive carbonylation of aryl fluorosulfonates (ArOSO2F) using syngas as an inexpensive and sustainable source of carbon monoxide and hydrogen. The conversion of phenols to aryl fluorosulfonates can be conveniently achieved by employing the inexpensive commodity chemical sulfuryl fluoride (SO2F2) and base. The developed continuous flow formylation protocol requires relatively low loadings for palladium acetate (1.25 mol%) and ligand (2.5 mol%). Good to excellent yields of aryl aldehydes were obtained within 45 min for substrates containing electron withdrawing substituents, and 2 h for substrates containing electron donating substituents. The optimal reaction conditions were identified as 120 °C temperature and 20 bar pressure in dimethyl sulfoxide (DMSO) as solvent. DMSO was crucial in suppressing Pd black formation and enhancing reaction rate and selectivity.

13.
J Sci Food Agric ; 100(4): 1757-1763, 2020 Mar 15.
Article in English | MEDLINE | ID: mdl-31825523

ABSTRACT

BACKGROUND: Fungicides are often applied to pears before they are kept in storage facilities. The scientific application of pesticides can reduce unnecessary exposure, which in turn could benefit both humans and the environment. RESULTS: We investigated dissipation behavior and residue distribution, and conducted risk assessments for prochloraz, pyraclostrobin, and tebuconazole in pears stored under different conditions using ultra-performance liquid chromatography (UPLC). The recoveries of the three fungicides ranged from 76.5% to 114.5%, and the coefficients of variation were 1.0%-8.5%. The half-life (t1/2 ) ranges for degradation of the three fungicides in Dangshan Su pear peel were 8.8-13.9 days after storage at 25 °C and 99.0-346.6 days after storage at 2 °C. Among the three fungicides, tebuconazole had the lowest residue concentration in pear pulp (maximum of 0.226 mg·kg-1 ) and the longest half-life (≥ 231.0 days). Accordingly, among these fungicides, tebuconazole is the most suitable for the preservation of Dangshan Su pears during storage. Finally, we analyzed samples of six pear varieties from markets in China and found that the residue concentrations of the three fungicides in pear pulp and fruit met Chinese standards. CONCLUSION: The results provide a scientific basis for rationalizing the use of prochloraz, pyraclostrobin, and tebuconazole, and improving the safety of pears for eating. © 2019 Society of Chemical Industry.


Subject(s)
Fungicides, Industrial/chemistry , Pesticide Residues/chemistry , Pyrus/chemistry , China , Consumer Product Safety , Food Contamination/analysis , Fruit/chemistry , Humans , Imidazoles/chemistry , Kinetics , Strobilurins/chemistry , Tandem Mass Spectrometry , Triazoles/chemistry
14.
Adv Drug Deliv Rev ; 142: 75-90, 2019 03 01.
Article in English | MEDLINE | ID: mdl-31150666

ABSTRACT

Lipid-based formulations (LBF) are widely used by industry and accepted by the regulatory authorities for oral drug delivery in the pharmaceutical and consumer healthcare market. Innovation in the LBF field is however needed in order to meet the demands of modern drugs, their more challenging problem statements and growing needs for achieving optimal pharmacokinetics (i.e., no food-effects, low variability) on approval. This review describes a new lipophilic salt / ionic liquid approach in combination with LBF, and how this salt strategy can be used to better tailor the properties of a drug to LBFs. The potential advantages of lipophilic salts are discussed in the context of dose escalation studies during toxicological evaluation, reducing the pill burden, increasing drug absorption of new drugs and in life-cycle management. Commentary on lipophilic salt synthesis, scale-up, LBF design and the regulatory aspects are also provided. These topics are discussed in the broad context of bringing the widely recognized advantages of LBFs to a broader spectrum of drugs.


Subject(s)
Drug Delivery Systems , Ionic Liquids/chemistry , Lipids/chemistry , Salts/chemistry , Animals , Drug Compounding , Legislation, Drug
15.
Rapid Commun Mass Spectrom ; 33(8): 778-788, 2019 Apr 30.
Article in English | MEDLINE | ID: mdl-30716180

ABSTRACT

RATIONALE: Deliberate and fraudulent origin mislabeling of Chinese green tea motivated by large price differences often brings significant food safety risks and damages consumer trust. Currently, there is no reliable method to verify the origin of green tea produced in China. Stable isotope and multi-element analyses combined with statistical models are widely acknowledged as useful traceability techniques for many agro-products, and could be developed to confirm the geographical origin of Chinese green tea and, more importantly, combat illegal green tea mislabeling and fraud. METHODS: An analytical strategy combining elemental analyzer/isotope ratio mass spectrometry (EA/IRMS) and inductively plasma coupled mass spectrometry (ICP-MS) with chemometrics tools was used to confirm the origin of green tea grown in the main tea production provinces around China. Stable C, N, H, O isotope ratios and twenty elements were measured to build mathematical discriminant models using unsupervised principal component analysis (PCA) and supervised linear discriminant analysis (LDA). Two main problems: (i) tracing the origin of Chinese green tea from different tea growing provinces (Zhejiang, Shandong, and other provinces); (ii) authentication of high-value Westlake Longjing tea from the Westlake region and surrounding areas in Zhejiang province, were investigated and assessed. RESULTS: The results demonstrated that PCA and follow-up LDA based on stable isotope and multi-element signatures can verify the geographical origin of Chinese green tea from different provinces, and even localized zones in the same province could be distinguishable, with discrimination accuracies higher than 92.3% and 87.8%, respectively. CONCLUSIONS: Geochemical fingerprinting techniques coupled with chemometric tools offer an accurate and effective verification method for the geographical origin of Chinese green tea, providing a promising tool to combat fraudulent mislabeling of high-value green tea.


Subject(s)
Camellia sinensis/chemistry , Isotopes/chemistry , Mass Spectrometry/methods , Tea/chemistry , Trace Elements/chemistry , China , Discriminant Analysis , Geography
16.
Sci Rep ; 7(1): 1452, 2017 05 03.
Article in English | MEDLINE | ID: mdl-28469128

ABSTRACT

Gold nanoparticles (AuNPs) aggregation-based colorimetric biosensing remains a challenge for bacteria due to their large size. Here we propose a novel colorimetric biosensor for rapid detection of Escherichia coli O157:H7 (E. coli O157:H7) in milk samples based on pH-regulated transformation of dimer/tetramer of Concanavalin A (Con A) and the Con A-glycosyl recognition. Briefly, antibody-modified magnetic nanoparticles was used to capture and concentrate E. coli O157:H7 and then to label with Con A; pH adjusted to 5 was then applied to dissociate Con A tetramer to release dimer, which was collected and re-formed tetramer at pH of 7 to cause the aggregation of dextran-modified AuNPs. The interesting pH-dependent conformation-transformation behavior of Con A innovated the design of the release from the bacteria surface and then the reconstruction of Con A. Therefore, we realized the sensitive colorimetric biosensing of bacteria, which are much larger than AuNPs that is generally not suitable for this kind of method. The proposed biosensor exhibited a limit of detection down to 41 CFU/mL, short assay time (~95 min) and satisfactory specificity. The biosensor also worked well for the detection in milk sample, and may provide a universal concept for the design of colorimetric biosensors for bacteria and virus.


Subject(s)
Antibodies, Bacterial/chemistry , Biosensing Techniques , Colorimetry/methods , Concanavalin A/chemistry , Escherichia coli O157/isolation & purification , Gold/chemistry , Magnetite Nanoparticles/chemistry , Animals , Antibodies, Bacterial/metabolism , Concanavalin A/metabolism , Dextrans/chemistry , Escherichia coli O157/chemistry , Food Contamination/analysis , Humans , Hydrogen-Ion Concentration , Limit of Detection , Magnetite Nanoparticles/ultrastructure , Milk/microbiology , Protein Multimerization
17.
J Agric Food Chem ; 64(28): 5633-43, 2016 Jul 20.
Article in English | MEDLINE | ID: mdl-27355562

ABSTRACT

Multielement and stable isotope (δ(13)C, δ(15)N, δ(2)H, δ(18)O, (207)Pb/(206)Pb, and (208)Pb/(206)Pb) analyses were combined to provide a new chemometric approach to improve the discrimination between organic and conventional Brassica vegetable production. Different combinations of organic and conventional fertilizer treatments were used to demonstrate this authentication approach using Brassica chinensis planted in experimental test pots. Stable isotope analyses (δ(15)N and δ(13)C) of B. chinensis using elemental analyzer-isotope ratio mass spectrometry easily distinguished organic and chemical fertilizer treatments. However, for low-level application fertilizer treatments, this dual isotope approach became indistinguishable over time. Using a chemometric approach (combined isotope and elemental approach), organic and chemical fertilizer mixes and low-level applications of synthetic and organic fertilizers were detectable in B. chinensis and their associated soils, improving the detection limit beyond the capacity of individual isotopes or elemental characterization. LDA shows strong promise as an improved method to discriminate genuine organic Brassica vegetables from produce treated with chemical fertilizers and could be used as a robust test for organic produce authentication.


Subject(s)
Brassica/growth & development , Fertilizers/analysis , Vegetables/growth & development , Agriculture , Brassica/chemistry , Carbon Isotopes/analysis , Discriminant Analysis , Food, Organic/analysis , Mass Spectrometry , Nitrogen Isotopes/analysis , Organic Agriculture , Vegetables/chemistry
18.
J Agric Food Chem ; 62(47): 11386-92, 2014 Nov 26.
Article in English | MEDLINE | ID: mdl-25369912

ABSTRACT

To further investigate the method of using δ(15)N as a marker for organic vegetable discrimination, the effects of different fertilizers on the δ(15)N in different growing stages of Brassica chinensis (B. chinensis) grown in uncultivated soil were investigated with a pot experiment. B. chinensis was planted with uncultivated soil and different fertilizer treatments and then harvested three times in three seasons consecutively. For the spring experiments in the years of 2011 and 2012, the δ(15)N value of B. chinensis, which increased due to organic manure application and decreased due to chemical fertilizer application, was significantly different (p < 0.05) with manure treatment and chemical treatment. The δ(15)N value of vegetables varied among three growing stages and ranged from +8.6‰ to +11.5‰ for the control, from +8.6‰ to +12.8‰ for the compost chicken manure treatment, from +2.8‰ to +7.7‰ for the chemical fertilizer urea treatment, and from +7.7‰ to +10.9‰ for the compost-chemical fertilizer treatment. However, the δ(15)N values observed in the autumn experiment of 2011 without any fertilizer application increased ranging from +13.4‰ to +15.4‰, + 11.2‰ to +17.7‰, +10.7‰ to +17.1‰, and +10.6‰ to +19.1‰, respectively, for the same treatments mentioned above. This result was not significantly different between manure treatment and chemical treatment. The δ(15)N values of soil obtained in the spring of 2011 during three growing stages were slightly affected by fertilizers and varied in the range of +1.6‰ to +2.5‰ for CK, +4.7‰ to +6.5‰ for compost treatment, +2.1‰ to +2.4‰ for chemical treatment, and +2.7‰ to +4.6‰ for chemical-compost treatment, respectively. High δ(15)N values of B. chinensis were observed in these experiments, which would be useful to supplement a δ(15)N database for discriminating organic vegetables. Although there was a significant difference between manure treatment and chemical treatment, it was still difficult to discriminate whether a labeled organic vegetable was really grown without chemical fertilizer just with a fixed high δ(15)N value, especially for the vegetables planted simultaneously with chemical and compost fertilizer.


Subject(s)
Brassica/drug effects , Brassica/growth & development , Fertilizers/analysis , Nitrogen/analysis , Brassica/chemistry , Crops, Agricultural/drug effects , Crops, Agricultural/growth & development , Nitrogen Isotopes/analysis , Organic Agriculture , Soil/chemistry , Vegetables/chemistry , Vegetables/drug effects , Vegetables/growth & development
19.
Chem Commun (Camb) ; (8): 952-3, 2003 Apr 21.
Article in English | MEDLINE | ID: mdl-12744315

ABSTRACT

Oxidation of a N-amino-ribonolactam with lead tetraacetate yields two cyclopentanes; the major one was transformed into the alpha-mannosidase inhibitor mannostatin A.


Subject(s)
Cyclopentanes/chemistry , Cyclopentanes/chemical synthesis , Lactams/chemistry , Amines/chemistry , Mannosidases/antagonists & inhibitors , Organometallic Compounds/chemistry , Oxidation-Reduction
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