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Abstract: In this study, a magnetic molecularly imprinted polymer (MMIP) based on Fe3O4@SiO2@CdTe (CdTe@MMIP) was synthesized using trichlorfon as template molecule, methacrylic acid (MAA) as the functional monomer, and ethylene glycol dimethacrylate (EGDMA) as the cross‐linker. The prepared MMIP was characterized, and the results showed that it exhibited good recognition and selective ability, offered a faster kinetics for the adsorption of trichlorfon. Scatchard analysis indicated that the binding sites in the CdTe@MMIP had two distinct groups (the high and low affinity binding sites). The saturated adsorption capacity (Qmax1) was 63.2 mg/g due to the low affinity binding sites, and another saturated adsorption capacity (Qmax2) was 71.4 mg/g due to the high affinity binding sites. Using it as sorbent, a method of molecularly imprinted magnetic solid‐phase extraction coupled with capillary electrophoresis (MIMSPE‐CE) for selective extraction, magnetic separation, and fast determination of trace trichlorfon in vegetable samples was developed. Under optimal conditions, appreciable sensitivity was achieved with a LOD of 30 μg/kg (S/N = 3) for the developed method. The relative standard deviation (RSD) for five replicate extractions of 0.05 mg/L trichlorfon standard solution was 4.2%. To evaluate the accuracy of this method, the blank cucumber and cauliflower samples spiked with trichlorfon were extracted and analyzed by this method with good recoveries ranging from 78.7% to 96.6%. Moreover, this method was applied to the quantitative detection of the trichlorfon residues in rape samples, and the results correlated well with that obtained from the gas chromatography method. [ABSTRACT FROM AUTHOR]

An organic-inorganic hybrid functionalized material was successfully synthesized by a surface molecular imprinting technique combined with a nonhydrolytic sol-gel (NHSG) process using acrylamide (AA) as the template, methacrylic acid as the functional monomer, methacryloxypropyltrimethoxysilane as the cross-linker and magnetic chitosan (CTS) microspheres as the support material. The adsorption ability and selectivity of this material toward AA was characterized. Experimental results showed that the imprinted polymer exhibited better recognition and selective performance toward AA than the nonimprinted polymer (NIP). The saturated binding capacity (Qmax) was 104.68 mg/g, and the equilibrium dissociation constant was 263.16 mg/mL. This prepared material also offered fast kinetics for the adsorption and desorption of AA. After shaking for 5 min, an adsorption capacity of 4.71 mg/g was obtained, and it almost reached the adsorption equilibrium within 90 min. [ABSTRACT FROM PUBLISHER]

An organic–inorganic hybrid functionalized material was successfully synthesized by a surface molecular imprinting technique combined with a nonhydrolytic sol–gel process using acrylamide as the template, methacrylic acid as the functional monomer, methacryloxypropyltrimethoxysilane as the cross-linker, and magnetic chitosan microspheres as the support material. The adsorption ability and selectivity of this material toward acrylamide was characterized. Experimental results showed that the imprinted polymer exhibited better recognition and selective performance toward acrylamide than the nonimprinted polymer. The saturated binding capacity (Qmax) was 104.68 mg/g, and the equilibrium dissociation constant was 263.16 mg/mL. This prepared material also offered fast kinetics for the adsorption and desorption of acrylamide. After shaking for 5 min, an adsorption capacity of 4.71 mg/g was obtained, and it almost reached the adsorption equilibrium within 90 min. [ABSTRACT FROM AUTHOR]

In this study, a new way to substitute the biology antibody was introduced by using a hydrophilic molecularly imprinted film, which was directly prepared on the well surface of MaxiSorp polystyrene 96-well plate by the bulk polymerization technique. This imprinted film exhibited good recognition and fast adsorption-desorption dynamics toward olaquindox. Using it as the recognition element, a fast and new direct competitive biomimetic enzyme-linked immunosorbent assay (BELISA) method for the determination of olaquindox in chick feed was developed. This BELISA method had low cross-reactivities of 6.2% and 12% for two analogues. Under the optimal conditions, the sensitivity (IC50) and the limit of detection (IC15) were 700 ± 60 µg L−1and 17.0 ± 1.6 µg L−1, respectively. The blank chick feed samples spiked with olaquindox at three levels were determined by this developed method with recoveries ranging from 82.0–96.0%. [ABSTRACT FROM AUTHOR]

How to determine the multipesticide residues in vegetables is an important problem. In this study, a new molecularly imprinted polymer was synthesized using O, O-dimethyl thiophosphoryl chloride, an intermediate for the manufacture of organophosphorous pesticides, as the template. Characterization test indicated that the synthesized polymer exhibited good recognition and selectivity for dichlorvos, methamidophos, acephate, folimat, monocrotophos, parathion-methyl, phosphamidon, and malathion. A molecularly imprinted SPE coupled to GC for simultaneous separation and determination of eight organophosphorous pesticides residues was developed. Under optimal conditions, the linear range of this method was 0.001-10.0 mg/L. The LOD of this method was in the range of 0.13-0.90 μg/kg. With a flow rate of 2.5 mL/min for loading 100 mL, the enrichment factor in the range of 25-480 for the eight organophosphorous pesticides was obtained. The RSD of the eight organophosphorous pesticides based on five replicates was from 1.50 to 4.09%. The accuracy of the proposed method was evaluated by recovery measurements on spiked samples, and good recovery rates ranging from 80.11 to 97.70% were achieved. Moreover, this method was evaluated for the quantitative detection of eight organophosphorous pesticide residues in leek and pakchoi samples. [ABSTRACT FROM AUTHOR]

Reducing sugar content increases several times during black garlic processing. This study aimed to explore the generation way of these reducing sugars. Molecular weight (Mw) distribution of saccharides and kinetics of polysaccharide degradation under thermal treatment were also evaluated. Polysaccharide degradation was by thermal treatment, not by enzymatic hydrolysis to make all the saccharides in black garlic less than 2 kDa. Thermal temperature affected the dynamic distribution of saccharides Mw. High temperature accelerated the degradation of high Mw polysaccharides to low Mw oligosaccharides and monosaccharides. The degradation kinetics did not obey first-order reaction over all thermal process. The Ea of garlic polysaccharides was 110.56 ± 3.25 kJ mol −1 . These results can provide a reference for further revealing the quality formation mechanism of black garlic. [ABSTRACT FROM AUTHOR]

In this communication, an adaptive grouping technique-based multilevel simply sparse method multilevel fast multipole algorithm (MLSSM-MLFMA) scheme is proposed to analyze objects with local fine structures efficiently. The MLSSM-MLFMA algorithm utilizes MLFMA to accelerate dealing with the boxes whose size is larger than 0.2 wavelength and uses MLSSM to decompose the boxes whose size is less than 0.2 wavelength. Meanwhile, the adaptive grouping technique is applied to improve the performance of MLSSM-MLFMA algorithm. The conventional octree-based grouping scheme divides the target into boxes with the same size at each level. It leads to some boxes that contain a large number of discrete unknowns, while some boxes contain fewer unknowns to simulate the object with local fine structures. Therefore, the computational efficiency of MLSSM-MLFMA algorithm will be improved. By using the proposed grouping technique, the memory requirements and computational times are much less than those of conventional octree-based grouping scheme for analyzing the objects with local fine structures. [ABSTRACT FROM AUTHOR]

• Electrochemical and optical sensors possess fast analysis speed and high sensitivity for CAP detection. • Nanomaterials can be used as signal amplifying material or carrier to further improve the sensitivity of the electrochemical and optical sensors for detection CAP. • Electrochemical and optical sensors have gained attention for CAP determination in real samples. • Current challenges and prospects in the field of electrochemical and optical sensors are proposed. 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. [ABSTRACT FROM AUTHOR]

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 0.16 mg L −1 and 0.13 μg L −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. [ABSTRACT FROM AUTHOR]

Various drying pretreatment techniques play an important role in the drying process. This study investigated the effect of ultrasound (US), osmosis (OM) and freeze-thaw (FT) pretreatments on the hot-air drying characteristics, physical characteristics, rehydration characteristics, and allicin content of garlic. The results showed that the application of different pretreatments increased the drying efficiency and reduced the total energy consumption, compared with unpretreated garlic. Particularly, drying garlic with US pretreatment reduced the drying time by 450, 270 and 90 min and the total energy consumption was 24.45%, 20.60% and 18.09% less at 50, 60 and 70 °C, respectively. These improvements attribute to an increasement in porous structure by US, which leads to an increase in water diffusion capacity. Moreover, US drying had lowest color difference, highest rehydration rate and allicin content. The Midilli model could satisfactorily describe the drying curves of US pretreated garlic. • The effect of three pretreatment methods on dehydration feature of garlic was studied. • Different pretreatment methods had a significant impact on the quality of dried garlic. • Ultrasound assisted with hot-air drying exhibited higher quality attributes and lower energy consumption. • Midilli model was the most suitable for describing the drying kinetics of garlic with ultrasound pretreatment. [ABSTRACT FROM AUTHOR]

Food-derived antihypertensive peptides have attracted increasing attention in functional foods for health promotion, due to their high biological activity, low toxicity and easy metabolism in the human body. Angiotensin converting enzyme (ACE) is a key enzyme that causes the increase in blood pressure in mammals. However, few reviews have summarized the current understanding of ACE inhibitory peptides and their knowledge gaps. This paper focuses on the food origins and production methods of ACE inhibitory peptides. Compared with conventional methods, the advanced technologies and emerging bioinformatics approaches have recently been applied for efficient and targeted release of ACE inhibitory peptides from food proteins. Furthermore, the transport and underlying mechanisms of ACE inhibitory peptides are emphatically described. Molecular modeling and the Michaelis-Menten equation can provide information on how ACE inhibitors function. Finally, we discuss the structure-activity relationships and other bio-functional properties of ACE inhibitory peptides. Molecular weight, hydrophobic amino acid residues, charge, amino acid composition and sequence (especially at the C-terminal and N-terminal) have a significant influence on ACE inhibitory activity. Some studies are required to increase productivity, improve bioavailability of peptides, evaluate their bio-accessibility and efficiency on reducing blood pressure to provide a reference for the development and application of health products and auxiliary treatment drugs. [ABSTRACT FROM AUTHOR]

This review highlights main bioactive compounds and important biological functions especially anticancer effects of the garlic. In addition, we review current literature on the stability and bioavailability of garlic components. Finally, this review aims to provide a potential strategy for using nanotechnology to increase the stability and solubility of garlic components, providing guidelines for the qualities of garlic products to improve their absorption and prevent their early degradation, and extend their circulation time in the body. The application of nanotechnology to improve the bioavailability and targeting of garlic compounds are expected to provide a theoretical basis for the functional components of garlic to treat human health. We review the improvement of bioavailability and bioactivity of garlic bioactive compounds via nanotechnology, which could promisingly overcome the limitations of conventional garlic products, and would be used to prevent and treat cancer and other diseases in the near future. [ABSTRACT FROM AUTHOR]

BACKGROUND Acrylamide ( AA) is of concern worldwide because of its neurotoxicity, genotoxicity and reproductive/developmental toxicity. Consequently, methods for minimizing AA formation during food processing are vital. RESULTS In this study, the formation and elimination of AA in an asparagine/glucose low-moisture model system were investigated by response surface methodology. The effect of garlic powder on the kinetics of AA formation/elimination was also evaluated. The AA content reached a maximum level (674.0 nmol) with 1.2 mmol of glucose and 1.2 mmol of asparagine after heating at 200 °C for 6 min. The AA content was greatly reduced with the addition of garlic powder. Compared to without garlic powder, an AA reduction rate of 43% was obtained with addition of garlic powder at a mass fraction of 0.05 g. Garlic powder inhibited AA formation during the generation-predominant kinetic stage and had no effect on the degradation-predominant kinetic stage. The effect of garlic powder on AA formation in bread and bread quality was also investigated. Adding a garlic powder mass fraction of 15 g to 500 g of dough significantly ( P < 0.05) reduced the formation of AA (reduction rate of 46%) and had no obvious effect on the sensory qualities of the bread. CONCLUSION This study provides a possible method for reducing the AA content in bread and other heat-treated starch-rich foods. © 2015 Society of Chemical Industry [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 10−6-102 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. • A SERS aptasensor was developed for the ultrasensitive detection of amantadine. • The sensor utilized magnetic-induced and aptamer-driven assemblies. • AuNRs@4-MPBA@Ag-c-DNA served as a reporter probe to amplify the 4-MPBA SERS signal. • The linear range of aptasensor was 10−6-102 mg L−1, with a LOD of 0.50 × 10−6 mg L−1. [ABSTRACT FROM AUTHOR]

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- κ B 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. [Display omitted] [ABSTRACT FROM AUTHOR]

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. [Display omitted] • First study on aroma changes in drying chive leaves and stems. • Pearson reveals the relationship between aroma precursors and key aroma compounds. • Metabolic pathways of key aroma compounds hypothesized. • Benzeneacetaldehyde, decanal, and methional are key aromas in FD-CIRD chive leaves. • (E)-2-heptenal and 1-octen-3-ol are key aromas in FD-CIRD chive stems. [ABSTRACT FROM AUTHOR]

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. • A molecularly imprinted gel (MIG)-based electrochemical sensor was built for TBHQ. • The MIG offer a high specificity recognition ability for tert-butylhydroquinone. • ZrO(OH) 2 @HCS was utilized for electrochemical signal amplification. • MIG-ZrO(OH) 2 @HCS/GCE enabled fast/sensitive/accurate monitoring of TBHQ in foods. [ABSTRACT FROM AUTHOR]

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 Co2+ was converted to Co3+ due to the introduction of Zr. The Co3+ in ZrCoOOH could react with MAL to form Co2+, which enhanced the electrooxidation current of Co2+. Therefore, the peak current of Co2+ 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. • A non-enzymatic electrochemical sensor was proposed for the indirect detection of malathion • The doping of Zr improved the conductivity and enlarged the specific surface area of CoOOH • Part of the Co2+ in ZrCoOOH was converted to Co3+ due to the single-atom Zr doping • ZrCoOOH was served as signal amplifier and detection probe • ZrCoOOH/GCE sensor was suitable for sensitive/accurate quantification of MAL in foods [ABSTRACT FROM AUTHOR]

• Highly conductive Nb 2 C@MWCNTs composites were synthesized via a hydrothermal method. • STAB enhanced the electrostatic attraction between Nb 2 C@MWCNTs and aqueous nitrite. • A Nb 2 C@MWCNTs-STAB/GCE DPV sensor allowed NO 2 − quantification at low concentrations. • Nb 2 C@MWCNTs-STAB/GCE could be applied for NO 2 − detection in real world samples. 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. [ABSTRACT FROM AUTHOR]

Herein, a precise and interference-free surface-enhanced Raman spectroscopy (SERS) ratio sensor was established for deltamethrin detection. A Ag@4-MBN@Ag nanoarray with abundant "hot-spots" was first prepared via liquid-liquid interface self-assembly (LLISA), then applied as a SERS substrate. The embedded 4-mercaptobenzonitrile (4-MBN) provided an interference-free nitrile stretching vibration (at 2226 cm−1) in "Raman biological-silent" region, which was utilized as SERS internal standard peak. The SERS intensity ratio I 1147 /I 2226 , where 1147 cm−1 corresponds to a SERS peak of deltamethrin, increased linearly with the logarithm of deltamethrin. Under optimized conditions, the developed SERS ratio sensor allowed sensitive detection of deltamethrin over the concentration range 10−5 to 103 μM, with a low limit of detection (LOD) of 3.16×10−7 μM. Recovery tests performed in deltamethrin-spiked pear and cabbage samples showed excellent recoveries (95.00% to 101.06%). Furthermore, the sensor was successfully applied to quantify deltamethrin in four kinds of food samples, with results consistent with analyses performed using gas chromatography. [Display omitted] • A precise and interference-free SERS ratio sensor was developed for sensitive detection of deltamethrin in foods. • Ag@4-MBN@Ag nanoarray was prepared as a SERS substrate using LLISA method. • The SERS ratio sensor exhibited a wide linear concentration range (10−5 to 103 μM) and low LOD (3.16×10−7 μM). [ABSTRACT FROM AUTHOR]

Pectins are highly sought after as food additives, functional ingredients, and structural polymers. So far, no study has been performed on the extraction, characterization, and application of pectins from garlic pomace. In this study, a medium-sized low-methoxyl pectin rich in rhamnogalacturonan-I (RG-I) and galactose was prepared from garlic pomace (termed "GP"; molecular weight, Mw, 324.08 kDa; degree of methyl esterification, DM, 48.10%; RG-I, 35.20%), via citric acid-water extraction at 65 °C for 120 min and ethanol precipitation. GP contained six neutral monosaccharides (fucose, rhamnose, arabinose, galactose, glucose, and xylose) and two acidic monosaccharides (galacturonic acid and glucuronic acid), and could protect zebrafish against metronidazole-induced oxidative damage. Compared with commercial citrus pectin, GP had a comparable Mw, much more RG-Is and homogalacturonans, higher protein and phenolic contents, higher degree of branching, lower crystallinity, higher thermal stability (over 30–377 °C), higher in vitro and in vivo antioxidant capacities, higher viscosity, and higher emulsifying and emulsion-stabilizing abilities. Accordingly, garlic pomace was a good source of RG-I-rich and galactose-rich pectins with high emulsifying and antioxidant capacities. GP can be used for making foods and pharmaceuticals possessing simultaneously high emulsifying, emulsion-stabilizing, and antioxidant capacities. This study demonstrates a sustainable garlic waste valorization approach. [Display omitted] • Pectins rich in RG-I and galactose (GP) were prepared from garlic pomace. • GP was a medium-sized low-methoxyl pectin with a high degree of branching. • GP showed more excellent emulsifying abilities than commercial citrus pectin. • GP effectively protected zebrafish against metronidazole-induced oxidative damage. • GP is a good ingredient/additive with high emulsifying and antioxidant capacities. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel garlic polysaccharide-Fe (III) complex was synthesized using garlic meal. • Structural characterization confirmed their interactions and complex formation. • These complexes showed good solubility and stability in gastrointestinal digestion. • These complexes had better improvement on the health status of IDA mice than FeSO 4. 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 -Fru f (1 → and → 2)- β - d -Fru f (6 → residues, and their interactions with Fe (III) reduced the crystallinity, increased the thermal stability, and altered the morphological features through targeting the O H stretching vibrations of the hydroxyl groups and affecting the C O C and O C O 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. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu-based MOFs with different particle sizes were hydrothermally synthesized. • Acetic acid was used as modifier to alter the MOF size, surface area and porosity. • Garlic organosulfur compounds adsorbed at the open metal sites in the Cu-MOFs. • A defective Cu-MOF exhibited outstanding OSCs adsorption performance in water. 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. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two ACE inhibitory peptides were obtained from garlic proteins by in silico screening. • They interacted with ACE mainly through hydrogen bonding as competitive inhibitors. • They showed good stability against temperature, pH and gastrointestinal digestion. • Two peptides effectively lowered blood pressure in spontaneously hypertensive rats. • They rebalanced the RAS and improved renal, cardiac and endothelial impairments. 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. [ABSTRACT FROM AUTHOR]

The discovery of nutritious dietary supplements and side effect-free therapeutics are a priority in the current scenario of increasing cancer cases. Natural anticancer polysaccharides have shown immense potential. As a class of biomacromolecules produced by a variety of species including plants, animals, fungi, bacteria and algae, polysaccharides have drawn considerable interest over the recent years as they possess anticancer activities with fewer side effects. Natural polysaccharides from different sources have various structures and anticancer activities. But it is difficult to compare their bioactivities with those of synthetic drugs for their inherently physicochemical properties, including poor water solubility, low molecular weight and branching degree. However, some chemical modification methodologies (e.g., sulfation, phosphorylation, selenylation and zinc impregnation) could significantly increase the water solubility, molecular weight by grafting other groups to boost their anticancer activity. Numerous studies have focused on the evaluation of anticancer mechanism of action for polysaccharides from different sources and further applications. Polysaccharides are considered as anti-tumor agents for their immunomodulatory activity and low toxicity and side effects. Numerous polysaccharides have been used for clinical or adjuvant treatment of tumors. However, the complex structure of some polysaccharides and their unclear anti-cancer mechanism of action brought great restrictions on their research and further clinical application. Therefore, it is important for human to resist tumors by elucidating the antitumor effects of polysaccharides from different resources and their correlation, discussing the application of anticancer polysaccharides in combination with chemotherapy drugs and anticancer vaccine adjuvants. • Polysaccharides show anti-tumor activity due to their immunomodulatory activity. • A variety of polysaccharides have been applied for clinical studies. • The lack of in vivo research led to insufficiently utilize polysaccharides. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the impact of blanching on the physical properties of frozen garlic cloves and to explore the relationship between quality changes and microstructure. A short‐term blanching treatment (100 °C for 45 s, 90 °C for 45 s, and 80 °C for 60 s) before freezing did not affect the total organosulfur compound content. In a preliminary research, blanching conditions were determined to be 100 °C for 45 to 80 s. Under these conditions, peroxidase was inactivated, but organosulfur compounds were retained. Mechanical and color tests showed a damaging effect of blanching and freezing on frozen garlic blanched for 60 and 80 s at 100 °C. Compared to frozen fresh garlic, frozen garlic treated by blanching for 45 s at 100 °C retained 2871.49 ± 200.24 µg/g of allicin, although 81.83% of peroxidase was inactivated; browning and hardness improved by 49.97 and 48.01%, respectively. According to scanning electron microscopy, significant damage to the microstructure was observed in both frozen fresh garlic and frozen garlic after 60 s and 80 s of blanching at 100 °C. Moreover, 1H low‐field nuclear magnetic resonance (LF‐NMR) indicated that blanching for 60 s and 80 s induced an increase in free water in garlic tissues, resulting in further damage after freezing. As peroxidase was efficiently inactivated, the microstructure and organosulfur compounds were better preserved, and blanching treatment at 100 °C for 45 s before freezing is a potential method for obtaining frozen garlic with high sensory and nutritional qualities. Practical Application: Freezing helps to overcome challenges associated with growing seasons and the deterioration of garlic during storage. After frozen garlic is thawed, it is prone to some undesirable changes, such as enzymatic browning and softening. Minimal blanching (45 s at 100 °C) pretreatment can help to maintain the bioactive compounds of garlic and prevent texture and color deterioration caused by freezing directly. [ABSTRACT FROM AUTHOR]

Garlic, an economically important vegetable, spice, and medicinal crop, produces highly enlarged bulbs and unique organosulfur compounds. Here, we report a chromosome-level genome assembly for garlic, with a total size of approximately 16.24 Gb, as well as the annotation of 57 561 predicted protein-coding genes, making garlic the first Allium species with a sequenced genome. Analysis of this garlic genome assembly reveals a recent burst of transposable elements, explaining the substantial expansion of the garlic genome. We examined the evolution of certain genes associated with the biosynthesis of allicin and inulin neoseries-type fructans, and provided new insights into the biosynthesis of these two compounds. Furthermore, a large-scale transcriptome was produced to characterize the expression patterns of garlic genes in different tissues and at various growth stages of enlarged bulbs. The reference genome and large-scale transcriptome data generated in this study provide valuable new resources for research on garlic biology and breeding. A chromosome-level genome assembly of garlic was constructed de novo in this study, providing new insights into genome evolution and allicin biosynthesis. The garlic assembly, along with large-scale transcriptome data, alsoprovides valuable resources for garlic research and breeding. [ABSTRACT FROM AUTHOR]

BACKGROUND Black garlic is produced by heating raw garlic at a high temperature for a long time without any additives. The thermal processing induces many chemical reactions, such as the Maillard reaction, which causes the color change from white to dark brown. Garlic contains a variety of amino acids, and the effect of each amino acid on browning is not fully understood. This work investigated the effect and mechanism of free amino acids on the browning of black garlic using model solutions containing garlic neutral polysaccharide, hydrolyzed garlic neutral polysaccharide, fructose, and free amino acids. RESULTS: A significant increase in reducing sugar was detected when garlic neutral polysaccharide was heated with glycine. The browning intensity of garlic neutral polysaccharide‐glycine model solution was obviously higher after heating at 80 °C compared with that of garlic neutral polysaccharide solution. The model solution containing histidine had the greatest browning degree. The histidine model has a stable pH value, and almost no 5‐hydroxymethylfurfural (5‐HMF) was detected. CONCLUSION: Amino acid can promote the breaking of the garlic neutral polysaccharide chain and can react with the fructose generated to form browning. Histidine has the greatest effect on the browning, because histidine could eliminate the inhibiting effect of organic acid on Maillard reaction due to the buffer ability, and histidine had high reactivity in the late stage of Maillard reaction. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Dried jujube (Ziziphus jujuba) was incubated at high temperature and humidity for 96 hr in blacking process and sampled every 12 hr. Results showed that the saccharose reduced from 195.6 to 3.1 g/kg rapidly in 24 hr. The total acid content was mild with 8.82 g/kg and increased to 23.45 g/kg by 177.21% with thermal processing for 96 hr. The contents of total polyphenols were enhanced during 0–48 hr processing, and the amount of the compound increased with treatment by 50.99%. The total reducing sugar increased 29.79% on 60 hr. cAMP was decreased with aging and ripening by 65.85%. 5‐HMF was keep growing to 3.52 g/kg. The volatile component had great change in black jujube fruits compared to untreated jujubes, especially treated in 12 hr. The results indicated that backing pretreatment can facilitate the generation of functional food materials and support the development of this nutrition product. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel 3D electrochemical sensor with selective recognition of SMR was successfully developed. • Highly conductive NH 2 -MWCNT@COF and MoS 2 nanosheets were employed to enhance the sensor signal. • The strategy offers a framework for rational development of electrochemical sensing platforms for more analytes. Abstract A novel three dimensional electrochemical sensor with signal amplification and selective recognition of sulfamerazine (SMR) was successfully constructed. First, highly conductive amino-functionalized carbon nanotubes@covalent organic frameworks (NH 2 -MWCNT@COF) and molybdenum disulfide (MoS 2) nanosheets were employed to modify the glassy carbon electrode (GCE) by simple physical deposition, in order to enhance the SMR response signal. Then, molecularly imprinted polymer (MIP) membrane was anchored on the surface of this modified GCE by electrochemical polymerization to achieve selective recognition for SMR. The electrochemical performance of the assembled electrochemical sensor was systematically investigated with differential pulse voltammetry and cyclic voltammetry. This obtained sensor displayed excellent selectivity for SMR and good reproducibility. Under optimal conditions, the sensor offered a wide current response for SMR from 3.0 × 10−7 to 2.0 × 10−4 mol L−1, with a limit of detection of 1.1 × 10−7 mol L−1. Furthermore, this developed sensor was successfully applied for the determination of SMR in pork and chicken samples with recoveries of 86.0%–102.0%, and results correlated well with those obtained by high-performance liquid chromatography. [ABSTRACT FROM AUTHOR]

Green discoloration is one of the most important problems that cause low quality of product in the processing of garlic, which can be induced by low-temperature stress. But the mechanism of low temperature-induced green discoloration is poorly understood. In the present study, the control garlic and three low temperature-treated garlic samples (stored at 4°C with 10, 15, and 40 days, respectively) were used for genome-wide transcriptome profiling analysis. A total of 49280 garlic unigenes with an average length of 1337 bp were de novo assembled, 20231 of which were achieved for functional annotation. When being suffered from 10, 15, and 40 days of low-temperature treatment, an increased degree of discoloration was observed, and a total of 4757, 4401, and 2034 unigenes showed a differential expression, respectively. Finally, 5923 differentially expressed genes (DEGs) were found to respond to the low-temperature stress, of which 3921 were identified in at least two treatments. Among these stress-responsive unigenes, there were large numbers of enzyme-encoding genes, which significantly enriched the pathway "proteasome," many genes of which are potentially involved in the garlic discoloration, such as 7 alliinase-encoding genes, 5 γ-glutamyltranspeptidase-encoding genes, and 1 δ-aminolevulinic acid dehydratase-encoding gene. These stress-responsive enzyme-encoding genes are possibly responsible for the low-temperature-induced garlic discoloration. The identification of large numbers of DEGs provides a basis for further elucidating the mechanism of low-temperature-induced green discoloration in garlic. [ABSTRACT FROM AUTHOR]

In this study, a molecularly imprinted polymer (MIP) was synthesized using trichlorfon as a template molecule. The MIP exhibited a high adsorption capacity toward trichlorfon. Using bovine serum albumin as a carrier, trichlorfon hapten was indirectly labeled with luminol, which competed with free trichlorfon for the combination with a biomimetic antibody of MIP. Based on this direct competitive format, a high throughput flow-injection chemiluminescent biomimetic immunoassay method was developed for fast detection of trace trichlorfon. The influencing factors were investigated and optimized. Under the optimal condition, a lower limit of detection (IC15) of 0.0024 mg/L was obtained using this method. This method was also used to detect the trichlorfon spiked in carrot and cabbage samples, and the results were also verified using the method of gas chromatography. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a molecularly imprinted polymer (MIP)‐fluorescent probe based on hydrophobic CdSe/ZnS quantum dots (CdSe/ZnS@MIP) was designed and synthesized by bulk polymerization for detecting methamidophos (MAP). The CdSe/ZnS@MIP was characterized by Fourier‐transform infrared spectroscopy, thermo‐gravimetric analysis and adsorption properties, and it exhibited good adsorption capacity and fluorescent stability, and excellent selectivity. Under optimal conditions, the fluorescence showed a good linear decrease in the range of 3.50 × 10−7–0.71 × 10−3 mol/L with a correlation coefficient of 0.995. The limit of detection of the fluorescent probe was 9.16 × 10−8 mol/L, and the relative standard deviation of the method for nine replicate analyses of 4.0 × 10−6 mol/L MAP was 4.1%. Apple and pear samples spiked with MAP at three levels were extracted and determined by the presented method with good recoveries (89.7%–94.9%). The accuracy of the method was verified by gas chromatography for the detection of kidney beans, leek and cucumber samples, and no significant difference was observed for the results of two methods. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a new sensor of molecularly imprinted solid‐phase extraction coupled with flow‐injection chemiluminescence for the detection of monocrotophos was fabricated. The molecularly imprinted polymer was synthesized by the bulk polymerization, using monocrotophos, methacrylic acid, and ethylene glycol dimethacrylate as the template molecule, functional monomer, and cross‐linker, respectively. The adsorption and recognition ability of the imprinted polymer toward monocrotophos was investigated. Factors influencing preconcentration of the analytes and sensitivity of the method were optimized. Under the optimal conditions, the chemiluminescence intensity was linearly proportional to the concentration of monocrotophos range from 0.0023 to 10 mg/L, and the limit of detection of the method was 0.001 mg/L. Rape (Brassica napus) and pakchoi (Brassica rapa subsp. chinensis) samples spiked with monocrotophos at three levels were analyzed by the developed method with recoveries between 89.3% and 105.9%. This method was successfully applied to the determination of monocrotophos in spinach samples, and the results were verified by gas chromatography method. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Black garlic is a distinctive garlic deep-processed product made from fresh garlic at high temperature and controlled humidity. To explore microbial community structure, diversity and metabolic potential during the 12 days of the black garlic processing, Illumina MiSeq sequencing technology was performed to sequence the 16S rRNA V3–V4 hypervariable region of bacteria. A total of 677,917 high quality reads were yielded with an average read length of 416 bp. Operational taxonomic units (OTU) clustering analysis showed that the number of species OTUs ranged from 148 to 1974, with alpha diversity increasing remarkably, indicating the high microbial community abundance and diversity. Taxonomic analysis indicated that bacterial community was classified into 45 phyla and 1125 distinct genera, and the microbiome of black garlic samples based on phylogenetic analysis was dominated by distinct populations of four genera: Thermus , Corynebacterium , Streptococcus and Brevundimonas . The metabolic pathways were predicted for 16S rRNA marker gene sequences based on Kyoto Encyclopedia of Genes and Genomes (KEGG), indicating that amino acid metabolism, carbohydrate metabolism and membrane transport were important for the black garlic fermentation process. Overall, the study was the first to reveal microbial community structure and speculate the composition of functional genes in black garlic samples. The results contributed to further analysis of the interaction between microbial community and black garlic components at different stages, which was of great significance to study the formation mechanism and quality improvement of black garlic in the future. [ABSTRACT FROM AUTHOR]

Burdock roots are healthy dietary supplements and a kind of famous traditional Chinese medicine, which contains large amounts of caffeoylquinic acid derivatives. However, little research has been reported on the preparative separation of these compounds from burdock roots. In the present study, a combinative method of HSCCC and semi-preparative HPLC was developed for the semi-preparative separation of caffeoylquinic acid derivatives from the burdock roots. The ethyl acetate extract of burdock roots was first fractionated by MCI macroporous resin chromatography and give three fractions (Fr. 1–3) from the elution of 40% methanol. Then, these three fractions (120 mg) were separately subjected to HSCCC for purification with the solvent system composed of petroleumether-ethyl acetate-methanol-water at different volume ratios, and themixtures were further purified by semi-preparative HPLC. As a result, a total of eight known caffeoylquinic acid derivatives including 3-O-caffeoylquinic acid (32.7 mg, 95.7%), 1,5-O- dicaffeoylquinic acid (4.3 mg, 97.2%), 3-O-caffeoylquinic acid methyl ester (12.1 mg, 93.2%), 1,3-O-dicaffeoylquinic acid (42.9 mg, 91.1%), 1,5-O-dicaffeoyl-3-O-(4-maloyl)-quinic acid (4.3mg, 84.5%), 4,5-O-dicaffeoylquinic acid (5.3mg, 95.5%), 1,5-O-dicaffeoyl-3-O-succinylquinic acid (8.7 mg, 93.4%), and 1,5-O-dicaffeoyl-4-O-succinylquinic acid (1.7 mg, 91.8%), and two new compounds were obtained. The new compounds were 1,4-O-dicaffeoyl-3-succinyl methyl ester quinic acid (14.6 mg, 96.1%) and 1,5-O-dicaffeoyl-3-O-succinyl methyl ester quinic acid (3.1 mg, 92.6%), respectively. The research indicated that the combination of HSCCC and semi-preparative HPLC is a highly efficient approach for preparative separation of the instability and bioactive caffeoylquinic acid derivatives from natural products. [ABSTRACT FROM AUTHOR]

In this study, a molecularly imprinted polymer that could selectively recognize trichlorfon was synthesized. Using the imprinted polymer as biomimetic antibody, a novel biomimetic immunoassay-capillary electrophoresis method with improved sensitivity was developed for the detection of trichlorfon. This method was based on the competitive reaction between quantum dot-labeled trichlorfon and free trichlorfon with the biomimetic antibody. Under optimal conditions, the limit of detection (IC15) and the sensitivity (IC50) of the method was 0.35 ± 0.021 μg/L and 0.81 ± 0.025 mg/L, respectively. To evaluate the accuracy of the method, trichlorfon spiked in the carrot and zucchini samples was determined, and the recovery was in the range of 80.1–95.3%. This method was also applied to the quantitative detection of trichlorfon residues in the edible rape and leek samples, and the results had a good correlation with those obtained using a gas chromatography method. [ABSTRACT FROM PUBLISHER]

This study aimed to prepare a complex of Cr (III) and garlic polysaccharides (GPs) and evaluate the in vitro and in vivo hypoglycemic activities of GPs and GP-Cr (III) complexes. The chelation of GPs with Cr (III) increased molecular weight, modified crystallinity, and altered morphological characteristics, through targeting the O H of hydroxyl groups and involving the C–O/O–C–O structure. The GP-Cr (III) complex had a higher thermal stability over 170–260 °C and higher stability throughout the gastrointestinal digestion. In vitro , the GP-Cr (III) complex exhibited a significantly stronger inhibitory effect against α -glucosidase compared with the GP. In vivo , the GP-Cr (III) complex at a high dose (4.0 mg Cr/kg body weight) generally had a higher hypoglycemic activity than the GP in (pre)-diabetic mice induced by a high-fat and high-fructose diet, based on indices like body weight, blood glucose levels, glucose tolerance, insulin resistance, insulin sensitivity, blood lipid levels, and hepatic morphology and function. Therefore, GP-Cr (III) complexes could be a potential Cr (III) supplement with an enhanced hypoglycemic activity. [Display omitted] • A promising garlic polysaccharide-Cr (III) complex was prepared. • Structural characterization confirmed their interaction and complex formation. • They showed good gastrointestinal stability and α -glucosidase inhibitory activity. • They had enhanced hypoglycemic activity in vivo in HFFD-induced pre-diabetic mice. [ABSTRACT FROM AUTHOR]

Many biomaterials are hydrophobic, making them attractive materials for the fabrication of surface enhanced Raman spectroscopy (SERS) substrates. Herein, we prepared a series of novel SERS substrates by loading graphene oxide (GO) and silver nanoparticles onto four different hydrophobic biomaterials (rose petals, lotus leaves, cicada wings or dragonfly wings). The obtained Ag@GO-biomaterial SERS substrates offered outstanding SERS performance. These substrates utilized both the electromagnetic mechanism and chemical mechanism to boost the SERS signal, as well as the concentrating effect owing to the hydrophobicity of biomaterials. The Ag@GO-rose petal SERS substrate showed the strongest signal enhancement capability, offering an LOD of 4.52 × 10-11 mol L-1 for the detection of the neomycin. Results encourage the wider use of hydrophobic biomaterials in SERS substrate construction and hazard monitoring. [Display omitted] • Four hydrophobic biomaterials used to construct Ag@GO-biomaterial SERS substrates. • The hydrophobicity of the biomaterials concentrated the analyte to enhance SERS. • Ag@GO-rose petal SERS substrate detected neomycin at trace levels (LOD 45.2 pM). • The gain effect of the hydrophobicity endowed by the microstructure of biomaterials on Raman signal was studied [ABSTRACT FROM AUTHOR]

Fast ω-gliadins were minor components of wheat storage proteins but a major antigen triggering allergy to wheat. Sixty-six novel full-length fast ω-gliadin genes with unique characteristics were cloned and sequenced from wheat and its relative species using a PCR-based strategy. Their coding regions ranged from 177 bp to 987 bp in length and encoded 4.28 kDa to 37.56 kDa proteins. On the base of first three deduced amino acids at the N-terminal, these genes could be classified into the six subclasses of SRL-, TRQ-, GRL-, NRL-, SRP- and SRM-type ω-gliadin genes. Compared by multiple alignments, these genes were significantly different from each other, due to the insertion or deletion at the repetitive domain. An analysis of the IgE-binding epitopes of the 66 deduced fast ω-gliadins demonstrated that they contained 0–24 IgE-binding epitopes. The phylogenetic tree demonstrated that the fast ω-gliadins and slow ω-gliadins were separated into two groups and their divergence time was 21.64 million years ago. Sequence data of the fast ω-gliadin genes assist in the study of the origins and evolutions of the different types of ω-gliadins while also providing a basis for the synthesis of monoclonal antibodies to detect wheat antigen content. [ABSTRACT FROM AUTHOR]

BACKGROUND Black garlic is a type of garlic product that is generally produced by heating raw garlic at high temperature with controlled humidity for more than 30 days. Black garlic has appeared on the market for many years. It is crucial to investigate the characteristics of quality formation of black garlic during processing at various temperatures. RESULTS In this study, fresh garlic was processed to black garlic at temperatures of 60, 70, 80 and 90 °C. Moisture, amino acid nitrogen and allicin contents decreased gradually during thermal processing of various temperatures. Reducing sugar, 5-hydroxymethylfurfural, total phenols, total acids contents and browning increased. The changing rate of quality indicators and flavour of black garlic varied at different temperatures. Browning intensity reached about 74 when black garlic aged. The sensory score was significantly higher in black garlic aged at 70 °C (39.95 ± 0.31) compared with that at other temperatures, suggesting that 70 °C might facilitate formation of good quality and flavour of black garlic during processing. CONCLUSION Temperature had a remarkable impact on the quality and flavour of black garlic. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

• A sensitive, rapid and selective SERS sensor for tryptamine was developed. • The TiO 2 @Ag@MIP sensor used TiO 2 NPs and Ag NPs for signal-amplification. • Adding a molecularly imprinted polymer enabled selective tryptamine recognition. • The sensor's linear range was 10−6–10−2 mol L−1, with a LOD of 4.85 × 10−7 mol L−1. • The developed sensor allowed tryptamine quantification in a variety of foods. 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. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-assembled gold nanorods array provided a stable SERS signal. • Signal-amplification was achieved through controlled release of 4-MB from DNA hydrogels. • SERS measurements of streptomycin using the sensor was successful (detection limit 4.85 × 10−3 nM). • This method can be utilized in development of biosensors by changing the aptamer sequence. 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. [ABSTRACT FROM AUTHOR]

• A signal on/off ratiometric PDA/NiS@HCS/GCE sensor was developed for sunset yellow. • Poly-dopamine was used as an internal reference probe and for signal amplification. • Highly conductive NiS@HCS aided SY quantification over a wide linear range. • The developed sensor exhibited excellent practical utility for SY detection in food. 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. [ABSTRACT FROM AUTHOR]

BACKGROUND Organophosphorus pesticides have been widely used in agricultural production. However, the wide use of organophosphate also results in pesticide residues on the plant, which are harmful to human health because of their potential mutagenic and carcinogenic properties. Therefore, it is vital to develop a sensitive and effective analysis method to control pesticide residues. RESULTS In this study, a novel molecularly imprinted capillary monolithic column was prepared using trichlorfon as the template molecule by combining non-hydrolytic sol-gel process with a molecular imprinting technique. The resulting material was characterized by scanning electron microscopy and Fourier transform infrared. Under capillary electrochromatography, the effects of voltage, pH, ACN content and concentration of buffer solution on the electro-osmotic flow ( EOF) of imprinted capillary monolithic column were evaluated in detail. Using this prepared material as stationary phase for capillary electrochromatography, a novel method of molecularly imprinted capillary electrochromatography ( MICEC) for the detection of trace trichlorfon residues in vegetables was developed. Under optimal conditions, appreciable sensitivity was achieved with a LOD ( S/ N = 3) of 92.5 µg kg−1 and method quantitation limit ( MQL) of 305.3 µg kg−1, respectively. The linear ranges of the calibration graph were 0.1 µg L−1 to 10 mg L−1. The peak area precision ( RSD) for five replicate extractions of 0.01 mg L−1 trichlorfon standard aqueous solution was 4.5%. To evaluate the accuracy of this method, the blank cucumber and cauliflower samples spiked with trichlorfon were extracted and analyzed by this method with good recoveries, ranging from 80.2% to 95.8%. Moreover, this method was successfully applied to the quantitative detection of the trichlorfon residues in leek samples. CONCLUSION With good properties of high sensitivity and simple pre-treatment, this MICEC method could provide a new tool for the rapid determination of trace trichlorfon residue in complex food samples. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Acrylamide has attracted worldwide concerns because of its demonstrated neurotoxicity, genetoxicity and reproductive-development toxicity. It is necessary to control acrylamide production during food processing and protect human health. RESULTS In this study, a functionalised material was synthesised by immobilising an ionic liquid onto an activated silica gel surface. The adsorption ability of the material towards acrylamide was evaluated, and the results showed that it had high adsorption capacity. Scatchard analysis indicated that the binding sites in the prepared material had two distinct groups (high and low affinity binding sites). The saturated adsorption capacity ( Qmax,1) was 7.9 mg g−1 due to the high affinity binding sites, and another saturated adsorption capacity ( Qmax,2) was 2.3 mg g−1 due to the low affinity binding sites. This prepared material also offered fast kinetics for adsorption of the acrylamide. Using this material as sorbent, a method of solid-phase extraction coupled with high-performance liquid chromatography ( SPE-HPLC) for analysis of acrylamide in foods was developed. Under optimal conditions, the limit of detection ( S/ N = 3) of this method for acrylamide was 2.1 µg kg−1, and the RSD for five replicate extractions of 50 μL−1 acrylamide was 4.5%. The blank potato and bread crumb samples spiked with acrylamide at different levels of 10.0 and 15.0 µg kg−1 were extracted and determined respectively by this developed method, and recoveries ranging from 83.0% to 89.1% were obtained. Finally, this method was applied to quantitative detection of acrylamide in bread crust and cracker samples. CONCLUSION With high sensitivity and pre-treatment simplicity, this SPE-HPLC method could provide a new tool for the rapid determination of acrylamide in the food samples. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]