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• Highly conductive COF@NH 2 -CNT was synthesized by a facile one-pot strategy at room temperature. • An electrochemical sensor which exhibited excellent electrocatalytic activity towards furazolidone was fabricated. • This paper offers a promising methodology applied to sensitive determination analytes in samples. In this study, we developed a facile one-pot strategy for immobilizing a covalent organic framework (COF) on an amino-functionalized carbon nanotube (NH 2 -CNT) support at room temperature. The COF@NH 2 -CNT composite obtained possessed a high specific surface area (147.3 m2 g−1), and good conductivity when deposited on the glassy carbon electrode (GCE). The COF@NH 2 -CNT/GCE sensor offered excellent analytical performance for the detection of the nitrofuran antibacterial agent furazolidone. The sensor offered a wide range furazolidone detection range from 0.2 μM to 100 μM, with a low limit of detection of 7.75 × 10-8 M. The recovery test was performed in chicken and lamb samples with satisfactory recoveries ranged from 87.8%–126.9%. The furazolidone residues in beef and pork samples were determined using the COF@NH 2 -CNT/GCE sensor and high-performance liquid chromatography. There was no significant difference between the two methods. The ability of the COF to efficiently adsorb furazolidone was a key to high sensitivity and fast response of the sensor platform. Results encourage the wider use of COFs in electrochemical sensor development. [ABSTRACT FROM AUTHOR]

Herein, a novel surface enhanced Raman spectroscopy (SERS) aptasensor was developed for amantadine (AMD) detection, based on magnetite nanoparticles coated with polyethylenimine, silver nanoclusters and aptamers (Fe 3 O 4 @PEI@AgNC-apt) as the capture probe and complementary DNA-modified gold nanorods (AuNRs@4-MPBA@Ag-c-DNA containing 4-mercaptophenylboric acid molecules) as the reporter probe. In the presence of AMD, the AMD and the reporter probe competed for the aptamer on the surface of the capture probe, resulting in the reporter probe detaching from the capture probe leading to a decrease in intensity of the SERS signal at 1067 cm -1 for 4-MPBA. Under optimal conditions, a good linear relationship was established between the SERS intensity at 1067 cm -1 and the logarithm of the AMD concentration over the range 10 -6 -10 2  mg L -1 , with a LOD of 0.50 × 10 -6  mg L -1 . The AMD levels in spiked samples were evaluated using the SERS aptasensor, with good recoveries ranging from 90.57% to 113.49% being obtained., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The present study identified the protective effects of garlic oligo/poly-saccharides of different chain lengths against dextran sulfate sodium (DSS)-induced colitis in mice and elucidated the structure-function relationships. The results showed that oral intake of garlic oligo/poly-saccharides decreased disease activity index, reduced colon shortening and spleen enlargement, and ameliorated pathological damage in the mouse colon. The dysregulation of colonic pro/anti-inflammatory cytokines was significantly alleviated, accompanied by up-regulated antioxidant enzymes, blocked TLR4-MyD88-NF-κB signaling pathway, enhanced intestinal barrier integrity, and restored SCFA production. Garlic oligo/poly-saccharides also reversed gut microbiota dysbiosis in colitic mice by expanding beneficial bacteria and suppressing the growth of harmful bacteria. High-molecular-weight polysaccharides exhibited stronger alleviating effects on DSS-induced colitic symptoms in mice than low-molecular-weight oligo/poly-saccharides did, probably due to their greater ability to be fermented in the colon. Taken together, this study demonstrated the anti-inflammatory effects of garlic oligo/poly-saccharides and revealed that high-molecular-weight polysaccharide fractions were more effective in alleviating DSS-induced colitis., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study aimed to investigate the effect of vacuum freeze drying combined with catalytic infrared drying (FD-CIRD) process on aromas, free amino acids, reducing sugars and free fatty acids in chive leaves and stems. Gas chromatography-mass spectrometry combined with multivariate data analysis revealed that dipropyl disulfide was the key aroma that distinguished the differences between chive leaves and stems. The key aromas benzeneacetaldehyde, decanal and 1-octen-3-ol enhanced FD-CIRD chive leaves and stems aromas. The free amino acid content was highest at FD-CIRD stage in all samples except for the control (FD), while the reducing sugar content was lowest. The content of unsaturated fatty acids gradually decreased at FD stage and increased at FD-CIRD stage. Additionally, correlation analysis revealed that phenylalanine was a potential precursor of benzacetenealdehyde, oleic and linolenic acids were potential precursors of decanal and 1-octen-3-ol. Therefore, FD-CIRD technique helps to improve the sensory profile of dried chives., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Herein, a novel molecularly imprinted gel (MIG)-based electrochemical sensor equipped with hydrated zirconium oxide@hollow carbon spheres (ZrO(OH) 2 @HCS) was developed for highly sensitive and selective detection of tert-butylhydroquinone (TBHQ) in foods. The MIG was synthesized by using L-histidine to rapidly cross-link cationic guar gum, acrylamide and TBHQ through intermolecular hydrogen bonds and electrostatic interactions at room temperature, which offered outstanding specific recognition performance for TBHQ. ZrO(OH) 2 @HCS possessing excellent conductivity and water dispersibility was employed for signal amplification. Under optimal conditions, the MIG-ZrO(OH) 2 @HCS/GCE sensor showed a wide dynamic detection range (0.025-100 μM) with a low limit of detection (6.7 nM). TBHQ recovery experiments were conducted in spiked peanut oil and milk powder, yielding excellent recoveries. Moreover, the sensor was successfully utilized to detect TBHQ levels in snowflake chicken cutlets, crispy fried pork and boneless chicken fillets, and the results were in agreement with those obtained by the high performance liquid chromatography method., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Herein, a novel electrochemical sensor based on zirconium-doped cobalt oxyhydroxide (ZrCoOOH) was proposed for highly sensitive non-enzymatic determination of malathion (MAL). The doping of Zr can improve the electrical conductivity of CoOOH, of which the transfer resistance was reduced from 241.1 Ω to 140.2 Ω. Furthermore, the X-ray photoelectron spectroscopy confirmed that part of Co 2+ was converted to Co 3+ due to the introduction of Zr. The Co 3+ in ZrCoOOH could react with MAL to form Co 2+ , which enhanced the electrooxidation current of Co 2+ . Therefore, the peak current of Co 2+ was served as detection probe for MAL. Under optimal conditions, the developed sensor established the linear relationship for MAL in the concentration range of 0.001-10.0 μM with a low limit of detection (0.64 nM). The constructed sensor was employed to detect MAL in food samples (peach, kiwi fruit, spinach and tomato), verifying the accuracy and practicability of the sensor., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Surface-enhanced Raman spectroscopy (SERS) detection platforms with high signal-to-noise ratio in the "biological-silent" region (1800-2800 cm -1 ) are presently being developed for sensing and imaging applications, overcoming the limitations of traditional SERS studies in the "fingerprint" region. Herein, a series of cyano-programmable Raman reporters (RRs) operating in the "biological-silent" region were designed based on 4-mercaptobenzonitrile derivatives and then embedded in core-shell Au@Ag nanostars using a "bottom-up" strategy to provide SERS enhancement and encapsulation protection. The approach enabled the "one-pot" readout interference-free detection of multiple bioamines (histamine, tyramine, and β-phenethylamine) based on aptamer-driven magnetic-induced technology. Three cyano-encoded SERS tags resulted in separate SERS signals for histamine, tyramine, and β-phenethylamine at 2220, 2251, and 2150 cm -1 , respectively. A target-specific aptamer-complementary DNA competitive binding strategy allowed the formation of microscale core-satellite assemblies between Fe 3 O 4 -based magnetic beads and the SERS tags, enabling multiple SERS signals to be observed simultaneously under a 785 nm laser excitation laser. The LODs for detection of the three bioamines were 0.61 × 10 -5 , 2.67 × 10 -5 , and 1.78 × 10 -5 mg L -1 , respectively. The SERS-encoded platform utilizing programmable reporters provides a fast and sensitive approach for the simultaneous detection of multiple biomarkers, paving the way for routine SERS analyses of multiple analytes in complex matrices.

Arctium lappa L . is widely consumed for its various biological effects, and polysaccharides are its main functional components. The present study aimed to evaluate the immunoregulatory effects of the main polysaccharides from burdock (ALP-1) and reveal the underlying mechanisms. ALP-1 consisted of fructose and glucose (14.57:1) and had a molecular weight of 2757 Da, with typical characteristics of (1 → 2)-linked linear fructans. Oral intake of ALP-1 significantly increased the number of colonic goblet cells, serum immunoglobulin A and immunoglobulin G levels, and fecal secretory immunoglobulin A content as well as up-regulated antioxidant enzymes and increased short chain fatty acid production. In addition, ALP-1 administration regulated pro/anti-inflammatory cytokines (i.e., interleukin (IL)-1β, IL-6, tumor necrosis factor-α, interferon-γ, and IL-10), intestinal microbiota structure, and the spatial information on key metabolites. Some gut-microbiota-mediated metabolic processes were also significantly altered. These results indicated that ALP-1 could exert beneficial effects on immune responses and intestinal health in healthy mice.

This study investigated the potential of garlic polysaccharides (GPs) from garlic pomace as iron carriers. The obtained GP-Fe (III) complexes had a higher molecular weight (5646 Da) and more fructose (90.46 %) than the GPs did and contained 9.7 % Fe (III). GPs were mainly composed of → 2)-β-d-Fruf (1 → and → 2)-β-d-Fruf (6 → residues, and their interactions with Fe (III) reduced the crystallinity, increased the thermal stability, and altered the morphological features through targeting the OH stretching vibrations of the hydroxyl groups and affecting the COC and OCO structures. The GP-Fe (III) complexes had high stability under simulated gastrointestinal digestion system and showed better therapeutic effects on iron deficiency anemia in mice than FeSO 4 did, evidenced by improved hematological parameters, restored iron levels, and attenuated oxidative damage. Thus, GP-Fe (III) complexes are promising as novel Fe (III) supplements for Fe-deficient individuals, and promote the high-value utilization of garlic pomace., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Organosulfur compounds (OSCs) in garlic-processing wastewater are decomposed and generated to toxic and harmful substances with unpleasant odors under anaerobic conditions. Herein, were report the successful development of novel copper-based metal organic framework (Cu-MOF) adsorbents with high adsorption capacities for OSCs in aqueous media. Defect-rich Cu-MOF-X samples, with particle sizes between 360 and 750 nm, synthesized hydrothermal in the presence of acetic acid (where X denotes the molar ratio of acetic acid relative to the pentadentate MOF linker H 4 PPYD). OSC adsorption experiments using allicin, ajoene and 2-ethenyl-4H-1,3-dithiine (2-VDT) showed that Cu-MOF-200 delivered fast adsorption kinetics and high OSC adsorption capacities (149.02-171.33 mg g -1 ) owing to the pore accessibility and range of adsorption sites in the MOF. FT-IR, Raman, and XPS analyses, together with density functional theory (DFT) calculations, verified the strong yet reversible adsorption of OSCs in Cu-MOF-200. Results guide the development of improved adsorbents for OSC capture from garlic-processing wastewater., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

This study aimed to screen novel angiotensin I-converting enzyme (ACE) inhibitory peptides from garlic proteins and to explore their underlying antihypertensive mechanisms in vivo. After simulated hydrolysis and in silico screening, two novel peptides (MGR and HDCF) were obtained with the highest ACE inhibitory activity (IC 50 of 4.50 μM and 26.38 μM) and acted as competitive inhibitors. They interacted with key residues in the ACE receptor mainly through hydrogen bonding and exhibited excellent stability against high temperature, extreme pH, and gastrointestinal digestion. In spontaneously hypertensive rats, MGR and HDCF effectively lowered blood pressure after single or continuous treatments. This was mainly achieved by balancing the renin-angiotensin system, improving renal and cardiac impairment, and regulating endothelial dysfunction. These findings suggested that garlic proteins were potentially suitable materials to prepare ACE inhibitory peptides and provided two promising candidates for ACE inhibition as functional food ingredients., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

SBEIIb ( Sobic .004G163700), SSSIIa ( Sobic .010G093400), and GBSSI ( Sobic .010G022600) genes that regulate starch synthesis in sorghum endosperm were transferred into Escherichia coli by transgenic technology. SBEIIb, SSSIIa, and GBSSI enzymes were separated and purified through a Ni column and analyzed by electrophoresis with molecular weights and activities of 91.57 84.57, and 66.89 kDa and 551 and 700 and 587 U/μL, respectively. Furthermore, they were applied to starch modification, yielding interesting findings: the A chain content increased from 25.79 to 89.55% for SBEIIb-treated waxy starch, while SSSIIa extended the A chain to form DPs of the B chain, with A chain content decreasing from 89.55 to 37.01%, whereas GBSSI was explicitly involved in the synthesis of B1 chain, with its content increasing from 9.59 to 48.45%. Modified starch was obtained, which could be accurately applied in various industries. For instance, we prepared a sample (containing 89.6% A chain content) with excellent antiaging and antidigestion properties through SBEIIb modification. Moreover, higher RS3 (34.25%) and SDS contents (15.75%) of starch were obtained through the joint modification of SBEIIb and SSSIIa. These findings provide valuable insights for developing sorghum starch synthesis-related enzymes and offer opportunities for improving starch properties through enzymatic approaches.

In this study, a simple and sensitive surface-enhanced Raman scattering (SERS) sensor based on gold nanostars@reduced graphene oxide (AuNS@rGO) was successfully developed for the detection of benzo[a]pyrene in foods. The detection strategy involved benzo[a]pyrene adsorption on reduced graphene oxide, followed SERS detection of adsorbed molecules. Owing to the large electric fields generated by the gold nanostars under laser irradiation, which greatly amplified the Raman signals of benzo[a]pyrene, very high sensitivity for the target analyte was achieved. Under optimized conditions, the SERS sensor exhibited a wide linear detection range for benzo[a]pyrene (from 0.1 μg L -1 to 10000 μg L -1 ), with a low limit of detection of 0.0028 μg L -1 . Chicken samples spiked with benzo[a]pyrene were assayed using the sensor, with recoveries ranging from 89.20% to 100.80%. The benzo[a]pyrene content in roasted mutton sample was quantified using the SERS sensor and a reversed-phase high-performance liquid chromatography method, with similar results being obtained., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Chloramphenicol (CAP) is a widely used antibiotic for the treatment of sick animals owing to its potent action and low cost. However, the accumulation of CAP in the human body can cause irreversible aplastic anemia and hematopoietic toxicity. Accordingly, development of various analytical techniques for the rapid detection of CAP in animal products and the related processed foods is necessary. Among these analytical techniques, electrochemical and optical sensors offer many advantages for CAP detection, including high sensitivity, simple operation and fast analysis speed. In this review, we summarize recent application of carbon nanomaterials, metal nanoparticles, metal oxide nanoparticles and metal organic framework in the development of electrochemical and optical sensors for CAP detection (2010-2022). Based on the advantages and disadvantages of nanomaterials, electrochemical and optical sensors are summarized in this review. The preparation and synthesis of electrochemical and optical sensors and nanomaterials in the field of rapid detection are prospected., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Herein, a molecularly imprinted surface-enhanced Raman spectroscopy (SERS) sensor was developed for the selective capture and sensitive detection of tryptamine in foods. The SERS sensor exploited silver nanoparticle-decorated TiO 2 (TiO 2 @Ag) substrates for Raman signal enhancement via synergistic effect of electromagnetic enhancement and photoinduced charge-transfer, whilst surface functionalization with the molecularly imprinted polymer ensured selective tryptamine capture. The SERS spectrum of tryptamine on the sensor closely matched that predicted by density functional simulations. The SERS intensity for tryptamine on the developed TiO 2 @Ag@MIP sensor increased linearly with the logarithm of the tryptamine concentration over the range of 10 -6 -10 -2 mol L -1 , with a LOD of 4.85 × 10 -7 mol L -1 . Tryptamine was detected in a spiked white vinegar sample, and its recoveries were in the range of 92.00%-111.40%. The SERS sensor could be used for the detection of tryptamine in actual samples., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Detrimental health effects caused by the intake of food contaminated with streptomycin have drawn concerns on effective monitoring using sensitive and selective methods. In this work, a DNA hydrogel surface enhanced Raman spectroscopy (SERS) sensor was successfully developed for the ultrasensitive determination of streptomycin residues in foods. The sensor used a DNA hydrogel containing DNAzyme (Pb-DNAzyme), triggering release of the Raman reporter 4-mercaptobenzonitrile, which was detected using a gold nanorods (AuNRs) array. The linear range of the sensor was 0.01-150 nM and the limit of detection was 4.85 × 10 -3  nM. Tests conducted with four streptomycin structural analogues confirmed the sensor was specific. Milk and honey samples spiked with streptomycin were analysed, resulting in standard recoveries in the range 98.2-117.3%. These findings demonstrated that such a sensor can be used for ultrasensitive detection of streptomycin in foods., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In this work, a novel ratiometric electrochemical sensor based on dual-functional poly-dopamine (PDA) and nickel sulfide@hollow carbon spheres (NiS@HCS) was successfully developed for sunset yellow (SY) detection. The NiS@HCS nanocomposite possessing a large specific surface area, good catalytic activity and excellent electrical conductivity was employed for signal amplification. PDA films prepared by electropolymerization acted as an internal reference probe and enhanced the sensitivity of the proposed sensor through electrostatic attraction between SY and PDA. Under optimized conditions, the developed PDA/NiS@HCS/GCE sensor allowed SY quantification over wide linear range (0.01-100 μM), with a low limit of detection of 0.003 μM. SY recovery tests were carried out in rice vinegar and cooking wine with satisfactory recoveries (83.50-112.80 %). Meanwhile, the content of SY in two kinds of carbonated drinks was determined using the constructed sensor and a UV-Vis spectrometry method, with no significant difference found in the results., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This study explored the potential of garlic polysaccharides (GPs) as a carrier for synthesizing GP-Zn (II) complexes to supplement Zn. According to the response surface analysis, the optimal preparation conditions were: mass ratio of GPs to Zn 2+ 1:0.21, temperature 53 °C, pH 5.9 and time 148.75 min, with the maximum chelation rate of 90.11%. The chelation of GPs and Zn 2+ involved O-H/C-O/O-C-O groups, increased crystallinity and altered absorption peaks of circular dichroism spectra, with a higher thermal stability, particle size and negative zeta potential. Compared with inorganic zinc salts, supplementation of GP-Zn (II) complexes showed enhance zinc supplementation effects in Zn-deficient mice model: increased body weight, organ index and Zn (II) levels in serum and liver, enhanced Superoxidedismutase (SOD) activity and alkaline phosphatase activity, decreased NO content and Malondialdehyde (MDA) content and improved colon and testicular morphology. Therefore, GP-Zn (II) complex can be used as a potential zinc supplement for Zn-deficient individuals., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Published by Elsevier Ltd.)

An electrochemical sensor based on stearyl trimethyl ammonium bromide - functionalized niobium carbide@multi-walled carbon nanotubes (Nb 2 C@MWCNTs-STAB) for signal amplification was successfully constructed for sensitive detection of nitrite (NO 2 - ). Niobium carbide@multi-walled carbon nanotubes (Nb 2 C@MWCNTs) with high electrical conductivity and water dispersibility were first prepared in a one-pot hydrothermal synthesis, after which cationic STAB was added to overcome the negative surface charge on the Nb 2 C@MWCNTs. The electrostatic attraction between Nb 2 C@MWCNTs-STAB and NO 2 - was improved by the STAB, which enhanced the sensitivity of the constructed sensor for NO 2 - . Under optimized conditions, Nb 2 C@MWCNTs-STAB/GCE exhibited excellent analytical performance for detection NO 2 - with two wide liner ranges (0.1-100 μmol L -1 and 100-2000 μmol L -1 ) and a limit of detection of 0.022 μmol L -1 . Nitrite recovery tests in milk and spinach samples showed recoveries in the range of 89.82-104.52%. The NO 2 - residues in ham and pickled vegetable (cedrela sinensis) samples were analysed using the presented sensor and a spectrophotometric method, with no significant difference found between the results of the two methods., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The aim of this study was to investigate the effects of the sequence of different thermal and mechanical treatments on the physicochemical parameters and microstructure of garlic paste, in order to improve the quality of the product. The total organosulfur compounds (OSCs) decreased steadily in blended-heated garlic, whereas OSCs decreased sharply after 2 min at 75 °C or 5 min at 85 and 95 °C in heated-blended garlic. After blanching for 5 min, allicin could maintain over 4.0 mg/g only at 75 °C; and OSCs of heated-blended garlic paste were found to drop by 29.56%, 90.63% and 94.79% at 75, 85 and 95 °C, respectively. In blended-heated garlic, the color values of L * (lightness) and a * (redness) decreased ( P  < 0.05), while the b * (yellowness) and C * (chroma) increased ( P  < 0.05), obtaining green discoloration garlic paste. The total color differences of blended-heated samples were greater than 12.08, which were 2-6 folds higher compared with heated-blended garlic. Total phenolic content and antioxidant activity decreased ( P  < 0.05) in all thermal treatments, thermal treatment of heated-blended garlic less than 5 min maintained over 30% of antiradical activity. The sequence of unit operations determined the pattern of garlic microstructure disruption, resulting in various enzymic and non-enzymic reactions. Our results indicated that use of heat treatment prior to blend processing is an effective and feasible method to inhibit garlic discoloration and retain high content of bioactive OSCs. It is recommended that garlic paste be prepared using heated-blended processing, with thermal processing limited to 75 °C for less than 5 min., (© Association of Food Scientists & Technologists (India) 2020.)

Fructose and its polysaccharides are widely found in fruits and vegetables, with the Maillard reaction of fructose affecting food quality. This study aimed to investigate the Maillard reaction of fructose using a fructose⁻histidine model system. The reaction process was characterized using fluorescence spectroscopy and ultraviolet spectroscopy. The effects of temperature, initial reactant concentration, initial fructose concentration, initial histidine concentration, and initial pH value on the different stages of the Maillard reaction were studied. Reactant reduction, ultraviolet and fluorescence spectra, acetic acid content, 5-hydroxymethylfurfural (5-HMF) content, and browning intensity were evaluated. The results showed that increasing the temperature and reactant concentration promoted the condensation reaction of fructose and amino acid in the early stage, the formation of intermediate products with ultraviolet absorption and fluorescence in the intermediate stage, and the formation of pigment in the final stage. The 5-HMF concentration decreased with increasing histidine concentration and initial pH value. Changes in the shape of ultraviolet and fluorescence spectra showed that the initial pH value affected not only the reaction rate, but also the intermediate product types. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging rate of the Maillard reaction products increased with increasing temperature, reactant concentration, and initial pH value.

Introduction: Increasing evidence has expanded the role of green tea from a traditional beverage to a source of pharmacologically active molecules with diverse health benefits. However, conclusive clinical results are needed to better elucidate the cancer-preventive and therapeutic effects of green tea polyphenols (GTPs). Areas covered: The authors describe GTPs' chemical compositions and metabolic biotransformations, and their recent developments in drug discovery, focusing on their cancer chemopreventive and therapeutic effects. They then review the recent development of GTP-loaded nanoparticles and GTP prodrugs. Expert opinion: GTPs possess potent anticarcinogenic activities through interfering with the initiation, development and progression phases of cancer. There are several challenges (e.g. poor bioavailability) in developing GTPs as therapeutic agents. Use of nanoparticle-based delivery systems has provided unique advantages over purified GTPs. However, there is still a need to determine the actual magnitude and pharmacological mechanisms of GTPs encapsulated in nanoparticles, in order to address newly emerging safety issues associated with the potential 'local overdose' effect. The use of Pro- epigallocatechin gallate (Pro-EGCG) as a prodrug appears to offer improved in vitro stability as well as better in vivo bioavailability and efficacies in a number of animal studies, suggesting its potential as a therapeutic agent for further study and development.

A direct competitive biomimetic immunosorbent assay method based on molecularly imprinted polymer was developed for the determination of trichlorfon. A CdSe/ZnS quantum dot label was used as the marker. The hydrophilic imprinted film was synthesized directly on the surface of a 96-well plate, and characterized by Fourier-transform infrared spectroscopy and thermo-gravimetric analyses. The method exhibited high stability, selectivity, and sensitivity. Under optimal conditions, the limits of detection and sensitivity of the biomimetic immunosorbent assay method were 9.0 μg L -1 and 5.0 mg L -1 (0.1 mg kg -1 and 62.5 mg kg -1 for vegetable sample), respectively. Low cross-reactivity values of 19.2% and 15.6% were obtained for the structural analogues. Spinach and rape samples spiked with trichlorfon were extracted and determined by this method with recoveries ranging from 83.6% to 91.1%. The method was applied for the detection of trichlorfon residues in leek and cucumber samples, and results correlated well with those obtained using GC., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Pesticide residue in vegetables is a serious problem that has adverse effects on human health. In our study, we designed and synthesized a molecularly imprinted polymer that can selectively recognize trichlorfon. Using the polymer material as biomimetic antibody, we developed a biomimetic immunoassay-capillary electrophoresis method with improved sensitivity for the detection of trichlorfon. We evaluated the competitive reactions between HRP labeled trichlorfon hapten and free trichlorfon with the biomimetic antibody. Factors that affected the sensitivity of our method were tested in detail. Under optimal conditions, the limit of detection (LOD, IC 15 ) and the sensitivity (IC 50 ) of this method were 0.16mgL -1 and 0.13μgL -1 for trichlorfon. We used this method to determine the trichlorfon spiked in the kidney bean and cucumber samples with recoveries ranging from 78.8% to 103%. We also detected residual trichlorfons in the leek samples, and these results were verified by gas chromatography method., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Black garlic produced from fresh garlic under controlled high temperature and humidity has strong antioxidant properties. To determine these compounds, five fractions (from F1 to F5) were separated and purified by elution with chloroform:methanol at different ratios (8:1, 6:1, 4:1, 2:1, and 0:1; v/v). The antioxidant activity of each fraction was analyzed. The results showed that F3 and F4 had higher phenolic contents and stronger 2,2-diphenyl-2-picrylhydrazyl radical scavenging activity than the others. Seven purified individual components were further separated using semipreparation high-performance liquid chromatography from these two intensely antioxidant fractions (F3 and F4), their structures were elucidated by high-performance liquid chromatography coupled to diode array detection, electrospray ionization, mass spectrometry, 1 H nuclear magnetic resonance, and 13 C nuclear magnetic resonance spectrometry. Three compounds including adenosine, uridine, and 2-acetylpyrrole were first identified in black garlic, except for 5-hydroxymethylfurfural, (1S, 3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid, and (1R, 3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid. The cellular antioxidant activities of uridine, adenosine, carboline alkaloids, 5-hydroxymethylfurfural, and ethyl acetate extracts were consistent with the results of in vitro experimental antioxidant properties. The results provide useful information for understanding the health benefits of black garlic products., (Copyright © 2016. Published by Elsevier B.V.)