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A colorimetric method is described for the determination of As(III). It is based on the use of 3-mercaptopropionic acid (3-MPA) assisted active site and interlayer channel dual-masking of oxidase-like Fe-Co-layered double hydroxides (Fe-Co-LDH). The Fe-Co-LDH acts as an oxidase-mimicking nanozyme with high activity. It catalyzes the oxidation of colorless 3,3′5,5′-tetramethylbenzidine (TMB) to form a blue product (oxTMB) with an absorption maximum at 652 nm. It is found that As(III) firmly anchors onto the Fe* sites of the 3-MPA-modified Fe-Co-LDH via forming a stable Fe─As(III)─3-MPA─As(III)─Fe structure. This results in masking the active sites and interlayer channels of the Fe-Co-LDH nanozyme. As a result, the presence of As(III) as well as 3-MPA specifically inhibit the LDH-catalyzed chromogenic reaction. Based on the above principle, a colorimetric assay was designed for the determination of As(III). It provided linear response in the 0.10~8.33 μM As(III) concentration range and a detection limit as low as 35 nM. The assay was applied to the quantitation of As(III), even in the presence of potential interferents including As(V), Hg(II) and Pb(II), in environmental and drinking water samples. [ABSTRACT FROM AUTHOR]

The present work aimed at evaluating the efficacy of gum Arabic–based edible coating enriched with red and white roselle extracts, on the postharvest quality of blueberry fruits during storage at 4 ± 0.5 °C. Physicochemical, phytochemicals, antioxidant capability, decay percent, and microbiological analyses of coated and uncoated blueberries were performed. The change rates of polyphenol oxidase (PPO) and guaiacol peroxidase (POD) activity were also measured. The coatings (gum Arabic with or without roselle extract) inhibited the growth of microbes (yeast and mesophilic aerobic bacteria) and enzyme activities (POD and PPO) of blueberries, reduced the degradation of anthocyanins and total phenolic as well as the weight loss and decay, and improved the firmness of blueberries. In comparison with gum Arabic coating, the gum Arabic enriched with roselle extract coating showed better performance on reducing microbes, enzyme activities, and anthocyanins degradation while enhancing the total phenolic content and decreasing the decay percentage. No significant differences were observed between the coated and uncoated blueberries in terms of their antioxidant capacities and pH values (p > 0.05). In conclusion, the combination of gum Arabic and roselle extract as edible coating materials can be used to conserve the quality of blueberry. [ABSTRACT FROM AUTHOR]

Abstract As pyrophosphate ion (PPi) and pyrophosphatase (PPase) play crucial roles in the pathological process of arthritis, determination of PPi and PPase in biological fluids turns to be of great importance for clinical diagnosis and therapy of arthritic diseases. In this work, we proposed a new fluorescent assay for PPi and PPase activity detection based on the competitive coordination chemistry of Fe3+ between PPi and an in situ formed fluorescent polydopamine (PDA). FeCo layered double hydroxide (FeCo-LDH) was explored as a peroxidase mimic to facilitate the in situ formation of fluorescent PDA from dopamine mediated by low-concentration H 2 O 2 within 30 min; The formed fluorescent PDA could be significantly quenched by Fe3+ through forming a PDA-Fe3+ complex structure; When PPi existed, it coordinated Fe3+ competitively against PDA and inhibited the fluorescence quenching of PDA by Fe3+; When PPi was hydrolyzed under the catalysis of PPase, the Fe3+ ion could quench the fluorescence of the formed PDA again. With these principles, our fluorescent assay was able to detect PPi and PPase activity specifically, providing detection limits down to 54 μM and 0.13 U/L, respectively. Furthermore, accurate determination of PPi and PPase activity in spiked human serum was also demonstrated using the developed assay. Graphical abstract Image 1 Highlights • In situ rapid synthesis of fluorescent PDA catalyzed by FeCo-LDH with low-concentration H 2 O 2. • Fe3+ significantly quenches the fluorescent PDA. • Coordination between PPi and Fe3+ inhibits the fluorescence quenching of PDA. • After PPase hydrolyzes PPi, the Fe3+ ion quenches the fluorescent PDA again. • The fluorescent PDA as a new probe for detection of PPi and PPase activity. [ABSTRACT FROM AUTHOR]

Highlights • Three different films were prepared by using two substances of starch, polyvinyl alcohol and chitosan. • The starch/polyvinyl alcohol/roselle anthocyanins film had the highest antioxidant activity and the best color stability. • The starch/polyvinyl alcohol/roselle anthocyanins film was used for pork freshness. Abstract This study aims to develop an intelligent indicating film based on biodegradable polymers incorporated with roselle anthocyanins to monitor pork freshness. Three different films were prepared by using two substances of starch, polyvinyl alcohol and chitosan. The UV–vis spectra and color of anthocyanins changed at pH 2–12. SEM photographs showed that the compatibility of films was improved with the addition of anthocyanins. Furthermore, the polyvinyl alcohol/chitosan/roselle anthocyanins film had the highest tensile strength (98.28 MPa). The starch/polyvinyl alcohol/roselle anthocyanins film had the highest antioxidant activity (524.07%) and the best color stability. The starch/polyvinyl alcohol/roselle anthocyanins film showed visible changes from red to green when employed to monitor the freshness of pork stored at 25 °C, before the TVB-N value of the pork gradually increased to the rejection limit (15 mg/100 g) at 36 h. Therefore, the indicator film can be used to monitor pork freshness for intelligent packaging. [ABSTRACT FROM AUTHOR]

Total acid content (TAC) and moisture content (MC) are very important parameters during Solid-State Fermentation (SSF) processes. The feasibility of using hyperspectral imaging (HSI) technology for predicting TAC and MC in vinegar cultures during SSF processes was investigated. Prediction models were constructed using variables selected from spectral and spatial data from associated 3-D hyperspectral datacubes to predict the relative content of TAC and MC for each pixel in the hyperspectral image. Models were developed using genetic algorithm (GA) optimization combined with partial least squares regression (PLS) dependent on the spectral variables yielded good prediction results for both TAC and MC. The determination coefficients ( R p 2 ) for TAC and MC were 0.8565 and 0.8162, respectively. Finally, the distribution maps of TAC and MC for a vinegar culture sample were obtained. These distribution maps could be implemented to estimate the uniformity of fermentation products during SSF. [ABSTRACT FROM AUTHOR]

Flowering tea has become a popular beverage consumed across the world. Anthocyanins content is considered as an important quality index of flowering tea. The feasibility of using near infrared (NIR) spectra at the wavelength range of 10,000-4000 cm-1 for rapid and nondestructive determination of total anthocyanins content in flowering tea was investigated. Ant colony optimization interval partial least squares (ACO-iPLS) and Genetic algorithm interval partial least squares (GA-iPLS) were used to develop calibration models for total anthocyanins content. Two characteristic wavelength regions (4590-4783, 5770-5963 cm-1), which corresponding to the ultraviolet/visible absorption bands of anthocyanins, were selected by ACO-iPLS. The optimal ACO-iPLS model for total anthocyanins content (R = 0.9856, RMSECV = 0.1198 mg/g) had better performance than full-spectrum PLS, iPLS, and GA-iPLS models. It could be concluded that NIR spectroscopy has significant potential in the nondestructive determination of total anthocyanins content in flowering tea. [ABSTRACT FROM AUTHOR]

Yao-meat is a traditional Chinese salted meat. Total volatile basic nitrogen content (TVB-N), total viable bacterial count (TVC), and residual nitrite (RN) level are important indexes of freshness for Yao-meat. This paper attempted the feasibility to determine TVB-N content, TVC and RN level in Yao-meat by a colorimetric sensor array chip. A color change profile for each sample was obtained by differentiating the image of sensor array before and after exposure to Yao-meat's volatile organic compounds. Genetic algorithm partial least squares regression (GA-PLS) was proposed to build the relationship between the TVB-N content, TVC, RN and the color change profiles of sensor array, and to select informative chemically responsive dyes for the three quality parameters. The GA-PLS models were achieved with R TVB-N=0.812, R TVC=0.856, R RN=0.855, in prediction set. This study demonstrated that colorimetric sensory array with GA-PLS algorithm could be used successfully to analyze the quality of Chinese traditional Yao-meat. [ABSTRACT FROM AUTHOR]

In China and Southeast Asian countries, the solid-state fermentation (SSF) process is maintained empirically, especially in fed-batch fermentation by layers. In this study, the feasibility of determination of the total acid content (TAC), pH value and moisture content of Zhenjiang balsamic vinegar during SSF process were investigated. Hyperspectral imaging technology (HSIT) was combined with an appropriate multivariate analysis method. A synergy interval partial leastsquare (siPLS) was used to select the efficient spectral subintervals and wavelengths by k-fold cross-validation during the development of model. The performance of the final model was evaluated by use of the root mean square error of cross-validation (RMSECV) and correlation coefficient (Rc) for the calibration set, and verified by use of the root mean square error of prediction (RMSEP) and correlation coefficient (Rp) for the validation set. The changes of TAC, pH value and moisture were obtained by normal standard methods. TAC was constantly increased during fermentation process. The change of pH value was from 3.6 to 3.99, which was appropriate for the growth of the main microbes and can inhibit the growth of other unnecessary bacteria in the fermentation process. The moisture was increased in all stages during SSF process. Besides, the experimental results showed that the optimum siPLS model for TAC was achieved by use of 7 PLS factors, when 4 spectral subintervals were selected by siPLS. The predicted precision of the best model obtained was: RMSECV = 0.625, Rc = 0.8316, RMSEP = 0.773, and Rp = 0.7965. The pH value was achieved using siPLS with 6 PLS factors. The predicted precision of the best model obtained was: RMSECV = 0.0465, Rc = 0.9455, RMSEP=0.0482, and Rp = 0.9321. Besides, the moisture content was achieved using siPLS with 4 PLS factors. The predicted precision of the best model obtained was: RMSECV = 0.2104, Rc = 0.8503, RMSEP = 0.2459, and Rp = 0.8277. Finally, the superior performance of the siPLS model was demonstrated by comparison with two other PLS models. The overall results indicated that HSIT can be successfully used for the measurement of TAC, pH value and moisture content in SSF, and the use of siPLS algorithm is the best means of calibration for modelling. Besides, in order to get the distribution map of TAC, principal component analysis (PCA) and stepwise linear regression (SMLR) were used to calculate the TAC in each pixel points. The distribution map of TAC in vinegar culture was obtained. The homogeneity of SSF also could be determined by hyperspectral imaging. [ABSTRACT FROM AUTHOR]

The content and distribution of chlorophyll in leaves are important indicators of nutrition information in plants. The objective of this study was to investigate the spectral behavior of the relationship between reflectance and chlorophyll content and to develop a technique for non-destructive chlorophyll estimation and distribution in leaves by using hyperspectral images. The hyperspectral imaging data cube of cucumber (Cucumissativus) leaves in the range of 450-850 nm were selected and preprocessed. A rectangle mesophyll about 100×200 pixels between the second and the third branch left of the main vein was selected as the region of interest (ROI). Spectra information of characteristic bands was extracted and used to set a model with measured chlorophyll content (spectra region extracted corresponding to region chlorophyll measured). The existing modeling methods, such as artificial neural networks (ANN), support vector machines (SVM), etc., can be used to achieve better results but are inconvenient for online applications due to the introduction of sophisticated algorithms. As an operation result of multiple spectrum values (addition, subtraction, multiplication, and division, combined with linear or nonlinear ways), vegetation indices, which play a role in indicating growth and biomass of vegetation, are significant in simplifying the model. Eight representative optical indices (or signatures), which were proposed as a function of the associated reflectance (Rλ) at the special wavelength (ë)nm, were used to predict the total chlorophyll content in cucumber leaves. Finally, (R695-705)-1-(R750-800)-1was identified as an optimum index, predicting the content of chlorophyll fairly well. The correlation coefficients of each model for calibration data set (rc) and validation data set (rp) were 0.8410 and 0.8286, while RMSEC (root mean square error of calibration) and RMSEP (root mean square error of predication) were the smallest (0.2045 mg/g and 0.2190 mg/g). The optimal model showed good stability and robustness due to two major advantages, namely the effects of "red edge" and baseline removal. On one hand, two feature bands (695-705 and 750-800 nm) of the model can be used to develop a kind of portable multispectral device. On the other hand, according to the model, chlorophyll content of the leaf was estimated at every pixel. A pseudo-color map was used to describe the law of chlorophyll distribution. On the map, it is evident that the content of chlorophyll is more in the mesophyll around the veins than in the veins. The edge is seen as less than the middle of the leaf, which is consistent with the actual distribution in the leaf. That is to say, it is a feasible analysis of chlorophyll content and distribution in cucumber leaves via the technique of hyperspectral images. Our results indicated that hyperspectral imaging was considerable for predicting chlorophyll content in leaves, thus allowing the chlorophyll content to be non-destructively detected in situ in living plant samples. In addition, the distribution map can also be used to analyze the accumulation of chlorophyll in spatial plants. Besides, it is easy to facilitate monitoring distribution and variation of chlorophyll in the tissues of plants. Further studies will provide a reliable way for processes that use photosynthetic pigments to participate in such as biochemical pathway, plant growth, and mechanisms of aging. [ABSTRACT FROM AUTHOR]

The morphological symptoms of phosphorus (P) deficiency in the leaves of mini-cucumber plants at early stages of development have features similar to that of early stage development in healthy plants. That similarity may lead to inappropriate visual diagnostics of phosphorus deficiency in analyzed samples. Because the differences in spectral properties of leaf tissues between phosphorus-deficient and healthy plants can be demonstrated, the feasibility of using near-infrared (NIR) spectroscopy for rapid and nondestructive diagnostics of phosphorus deficiency in mini-cucumber plants was investigated. Leaf reflection spectra in the wavelength range of 10 000-4000 cm−1were measured before the appearance of morphological changes caused by phosphorus deficiency. Least-squares support vector machine (LS-SVM), a method for recognizing patterns, was applied to identify phosphorus-deficient plants. Parameters (γ, σ2) of LS-SVM were optimized by cross-validation, and several conventional, two-class classification methods such as linear discrimination analysis and K-nearest neighbors were also used comparatively for identification. Identification rates in excess of 86% were achieved with the LS-SVM model for both the training set and the prediction set. The overall results indicated that NIR spectra combined with LS-SVM could be used efficiently for pre-visual diagnostics of phosphorus deficiency in mini-cucumber plants. [ABSTRACT FROM AUTHOR]

Abstract: The feasibility that used the efficient selection of wavelength regions in FT-NIR for a rapid and conclusive determination of fruit inner qualities such as soluble solids content (SSC) of apples was investigated. An apples NIRS acquisition device was developed in this study. With this device, the apple was rolling while collecting the NIR spectroscopy. Graphically oriented local multivariate calibration modeling procedures such as interval partial least-squares (iPLS), backward interval partial least-squares (BiPLS), and forward interval partial least-squares (FiPLS) were applied to select the efficient spectral regions that provides the lowest prediction error, in comparison to the full-spectral model. Among 40 intervals, the optimal combinations of 10 spectral intervals were chosen by FiPLS to obtain a satisfactory result, while those of 5 by BiPLS for the simplicity. The intervals chosen by BiPLS are not the same as those by FiPLS, due to the different algorithm of the two methods. In the determinations, a root mean square error of prediction (RMSEP) of 0.732 was obtained after interval selection. [Copyright &y& Elsevier]

• Bilayer films were developed using agar, anthocyanins, gellan gum and TiO 2. • TiO 2 improved the illumination stability of the film. • Gellan gum-TiO 2 contributed to the electrochemical writing on the film. • The bilayer film was sensitive to NH 3 , trimethylamine and dimethylamine. • The bilayer film showed color changes during spoilage of pork and silver carp. Amine-responsive bilayer films were developed by using agar (AG), anthocyanins (AN), gellan gum (GG) and TiO 2 nanoparticles for visual monitoring of meat spoilage. The AG-AN layer worked as the sensing layer to volatile amines, while GG-TiO 2 layer served as the light barrier layer and simultaneously the conducting layer to improve the illumination stability and electrochemical writing ability of the AG-AN layer, respectively. The Scanning electron microscopy (SEM) images and X-ray diffraction (XRD) spectra indicated the successful fabrication of bilayer films. Illumination experiments showed that the incorporation of TiO 2 in the GG-TiO 2 layer significantly improved the illumination stability of AN in the AG-AN layer. Meanwhile, electrochemical writing process could be easily conducted on the AG-AN layer in the presence of GG-TiO 2 layer, indicating the feasibility of ink-free printing on bilayer biopolymer films. The AG-AN/GG-2%TiO 2 film presented a limit of detection of 0.018 mM to trimethylamine (TMA), a typical basic gas generated during meat spoilage. Based on its good illumination stability and sensing ability to basic gases, the AG-AN/GG-2%TiO 2 film exhibited rose red-to-green color changes along with the spoilage of pork and silver carp, indicating its great potential for monitoring meat spoilage in intelligent food packaging. [ABSTRACT FROM AUTHOR]

[Display omitted] • RuBisCo co-pigments showed high copigmentation effects on P3C5G. • RuBisCo drastically shifted p K H -values and hyperchromicity of P3C5G. • The half-life of P3C5G was doubled when adding RuBisCo. • RuBisCo interacted with P3C5G via H-bonding and π-π stacking. • P3C5G altered the secondary structure of RuBisCo. The co-pigmentation behaviour of RuBisCo proteins (with different concentrations) on peonidin-3-O-p-coumaroylrutinoside-5-O-glucoside (P3C5G, extracted from Rosetta potato's peels) conjugates in isotonic sport drinks (ISD) was examined using multispectral, thermal stability kinetics, and libDock-based molecular docking approaches. The colorant effects of RuBisCo on P3C5G were also studied in spray-dried microencapsulated ISD-models. RuBisCo, especially at a concentration of 10 mg/mL in ISD, showed a co-pigmentation effect on the color of P3C5G, mostly owing to its superior hyperchromicity, p K H -levels, and thermal stability. Results from multispectral approaches also revealed that RuBisCo could noncovalently interact with P3C5G as confirmed by libDock findings, where P3C5G strongly bound with RuBisCo via H-bonding and π–π forces, thereby altering its secondary structure. RuBisCo also preserved color of P3C5G in ISD-powdered models. These detailed results imply that RuBisCo could be utilized in ISD-liquid and powder models that might industrially be applied as potential food colorants in products under different conditions. [ABSTRACT FROM AUTHOR]

The development of environment‐friendly bacteriostats in humid atmosphere is designated as a crucial step pointing to sustainable antibiotic‐free alterative. Thanks to the excellent biosafety and intrinsic bacteriostatic attributes, bioactive phytochemical formulations become a fascinating substitute for traditional antibiotics; yet, it remains a challenge to deliver them toward moisture‐activated bacteriostatic application due to the unclear release mechanism and bacteriostatic behavior. Benefitting from "green" metal–organic frameworks (MOFs) evolved from natural γ‐cyclodextrin (γ‐CD) and potassium ion (K+), an intelligent moisture‐activated phytochemical formulation is developed, which is featured by grafting bacteriostatic vanillin (a specific phytochemical extracted from Rutaceae vanilla bean) into microporous structure of MOFs via ligand implantation mechanism. According to the molecular simulation docking, the dominant pattern of host–guest structure is characteristic for H‐bond with a length of 1.9 Å, beneficial for the sterling adsorption capacity. Nevertheless, under moisture exposure, the intermolecular H‐bond is disrupted for vanillin release to destroy bacterial membrane structure, accelerate protein decomposition, and especially inhibit virulence gene transcription of cfa gene in Escherichia coli and sea gene in Staphylococcus aureus, directing to upgrade the insights into the bacteriostatic potency of phytochemicals in high‐humidity circumstance. [ABSTRACT FROM AUTHOR]

A novel light-addressable potentiometric sensor (LAPS), on the micrometer scale, is presented for rapid determination of blood and urine glucose. A LAPS chip with <150 μm working diameter is fabricated using standard semiconductor technique, and assembled onto an optical fiber of a laser module to form a micro-sized device. An active circuit design, containing on-board light driver and transimpedance amplifier, is introduced to simplify electronic connection and improve signal quality. Glucose-sensitive layer is obtained by drop-coating glucose oxidase onto the working surface of the LAPS. Under optimized optical and electrochemical conditions, the proposed sensor is used to detect glucose in laboratorial and real samples. In a wide range as 0.01–100 mM, a log-linear relationship is well established, and the response time is less than 10 s. Limit of detection and limit of quantitation of this method are found to be 0.003 and 0.01 mM, respectively. Data from the proposed method are validated with those from a certified clinical analyzer, and no statistic difference is found. Image 1 • Light-addressable potentiometric sensor is firstly realized on the micrometer scale. • Laser module is used to provide precise illumination and form compact device. • Active circuit design simplifies electronic connection and improves signal quality. • As-fabricated sensor is validated in sensing blood and urine glucose. [ABSTRACT FROM AUTHOR]

For the first time, the characteristics, formulas, challenges, technical concerns, and health benefits of the nutritious appetizers were comprehensively narrated. Research findings from available literature were compiled, and the possible approaches that could be employed to improve nutritious bar stability and amend their producibility were presented. The post-processing changes in the nutritious bars, such as their texture hardening and browning, were extensively studied as compared to their processing. The proteinaceous and fibrous appetizers showed some health benefits with acceptable sensory properties. Fortifying nutritious appetizers further with phytochemicals and modifying the structure of the appetizers were recently suggested. Although the current evidence is promising, further studies are still needed to enhance the sensory paldratability of the nutritious bars/balls. [ABSTRACT FROM AUTHOR]

Molecularly imprinted polymers (MIPs) are tailor-made functional composites which selectively recognize and bind the target molecule of interest. MIP composites are products of the massively cross-linked polymer matrices, generated via polymerization, with bio-inspired recognition cavities that are morphologically similar in size, shape and spatial patterns to the target conformation. These features have enabled researchers to expand the field of molecular recognition, more specifically for target with peculiar requirements. Nevertheless, MIPs alone are characterized with weak sensitivity. Besides, nanoparticles (NPs) are remarkably sensitive but also suffer from poor selectivity. Intriguingly, the combination of the two results in a highly sensitive and selective MIP composite. For instance, the conjugation of different functional NPs with MIPs can generate new flexible target capture tools, either a dynamic sensor or a novel drug delivery system. In this regard, although the technology is considered an established and feasible approach, it is still perceived as a burgeoning technology for various fields, which makes it unceasingly worthy reviewing. Therefore, in this review, we attempt to give an update on various custom-made biosensors based on MIPs in combination with various NPs for the detection of mycotoxins, the toxic secondary metabolites of fungi. We first summarize the classification, prevalence, and toxicological characteristics of common mycotoxins. Next, we provide an overview of MIP composites and their characterization, and then segment the role of NPs with respect to common types of MIP-based sensors. At last, conclusions and outlook are discussed. [ABSTRACT FROM AUTHOR]

Herein, an all-solid light addressable potentiometric sensor (LAPS) is presented for determination of cadmium (Cd) in rice. On the working surface of the LAPS, reduced graphene oxide (RGO) is introduced as a part of ion-to-electron transducer to improve ionophore behaviors. The composite modification of RGO and ionophore is validated with scanning electron microscopy. The as-fabricated sensor presents a rapid response in less than 10 s to target Cd. Meanwhile, it shows lower noise (0.23 mV) and better limit of detection (0.002 mg L −1 ) than LAPS (control) without RGO modification (0.37 mV; 0.008 mg L −1 ). With the proposed method, satisfactory precision, accuracy and selectivity are also established. This method is adopted in an extensive survey for 25 rice samples from 5 regions in China. The results are in very good agreement with those obtained using inductively-coupled plasma-mass spectrometry. [ABSTRACT FROM AUTHOR]

Dicofol is a highly toxic residual pesticide in tea, which seriously endangers human health. A method for detecting dicofol in tea by combining stoichiometry with surface-enhanced Raman spectroscopy (SERS) technology was proposed in this study. AuNPs were prepared, and silver shells were grown on the surface of AuNPs to obtain core–shell Au@AgNPs. Then, the core–shell Au@AgNPs were attached to the surface of a PDMS membrane by physical deposition to obtain a Au@AgNPs/PDMS substrate. The limit of detection (LOD) of this substrate for 4-ATP is as low as 0.28 × 10−11 mol/L, and the LOD of dicofol in tea is 0.32 ng/kg, showing high sensitivity. By comparing the modeling effects of preprocessing and variable selection algorithms, it is concluded that the modeling effect of Savitzky–Golay combined with competitive adaptive reweighted sampling–partial least squares regression is the best (Rp = 0.9964, RPD = 10.6145). SERS technology combined with stoichiometry is expected to rapidly detect dicofol in tea without labels. [ABSTRACT FROM AUTHOR]

BACKGROUND: The presence of foreign materials (FM) not only reduces the commercial value of tobacco and the quality of cigarette products, but also affects the aroma and flavor of cigarettes. Existing tobacco deblending equipment has received little study with respect to homochromatic FM. In the present study, visible‐near infrared (VIS‐NIR) hyperspectral imaging technique combined with chemometrics were used to identify and visualize the homochromatic FM on the surface of thining tobacco. A comparison with conventional vision method was made to analyze the feasibility of the method. The importance of detecting FM in cut tobacco was further demonstrated by first studying the volatile organic compounds produced in cigarette mixed FM smoke and their effects on human health before conducting hyperspectral experiments. RESULTS: The results indicated that solid‐phase microextraction and gas chromatography mass spectrometry could detect volatile organic compounds in mainstream cigarette smoke that were not cigarette components and affected consumer health. Then, spectral features of the samples were extracted from hyperspectral images for building identification models to distinguish FM from cut tobacco. The visual RGB values of cut tobacco and FM were also used for the analysis of the recognition models. The results showed that the accuracy, precision and recall reached 100.00% using the back propagation artificial neural network classification model based on the principal component analysis raw wavelengths. The visualization results based on the optimal model produced clearer localization than conventional computer vision method. CONCLUSION: The present study revealed that the VIS‐NIR hyperspectral imaging technology had advantage in the detection and localization of FM on the surface of thinning tobacco, which provided a foundation for improving the quality and safety of cut tobacco production. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Hyperspectral images (431–962 nm) and partial least squares (PLS) were used to detect the distribution of triterpene acids within loquat ( Eriobotrya japonica ) leaves. 72 fresh loquat leaves in the young group, mature group and old group were collected for hyperspectral imaging; and triterpene acids content of the loquat leaves was analyzed using high performance liquid chromatography (HPLC). Then the spectral data of loquat leaf hyperspectral images and the triterpene acids content were employed to build calibration models. After spectra pre-processing and wavelength selection, an optimum calibration model ( Rp = 0.8473, RMSEP = 2.61 mg/g) for predicting triterpene acids was obtained by synergy interval partial least squares (siPLS). Finally, spectral data of each pixel in the loquat leaf hyperspectral image were extracted and substituted into the optimum calibration model to predict triterpene acids content of each pixel. Therefore, the distribution map of triterpene acids content was obtained. As shown in the distribution map, triterpene acids are accumulated mainly in the leaf mesophyll regions near the main veins, and triterpene acids concentration of young group is less than that of mature and old groups. This study showed that hyperspectral imaging is suitable to determine the distribution of active constituent content in medical herbs in a rapid and non-invasive manner. [ABSTRACT FROM AUTHOR]

A novel method of real-time-range measurement, characterized by pre-sampling forecast and balanced-range switching, is introduced in this study. According to this method, raw current signals in biosensing procedures may be measured and recorded with real-time-optimized instrumental settings. A low-cost and high-performance potentiostat is developed to validate the proposed method. The transient process of real-time-range measurement is investigated to optimize sampling interval and circuit parameters. Typical time consumption of a sampling cycle is less than 100 μs, which makes high-speed and real-time-range measurement possible. The proposed method also brings excellent current resolution that is better than 0.8 pA. It improves weak signals in stripping determinations, and is particularly suitable for biological samples. As-fabricated potentiostat, coupled to a nano-Au-modified microband electrode array, is adopted in high-speed stripping determinations towards human blood lead levels (HBLLs). Accuracy and precision of this method are validated with certified reference material (CRM). Obtained values (4.31 ± 0.18 μg L −1 ) meet with certified levels of CRM (4.24 ± 0.11 μg L −1 ). Coefficient of variation percent (CV %) is no more than 5.0% for intra- or inter-assay analyses. Finally, this method is utilized for human population based study. Two groups of data, from this method and inductively coupled plasma mass spectrometry (ICP-MS), are analyzed using a statistic tool of t -test, and no statistically significant difference is found. [ABSTRACT FROM AUTHOR]

Edible bird’s nest (EBN) is a precious functional food in Southeast Asia. A rapid and nondestructive method for determining the distribution map of protein content (PC), carbohydrate content (CC) and sialic acid content (SAC) on EBN sample was proposed. Firstly, 60 EBNs were used for hyperspectral image acquisition, and components content (PC, CC and SAC) were determined by chemical analytical methods. Secondly, the spectral signals of EBN hyperspectral image and EBN components content were used to build calibration models. Thirdly, spectra of each pixel in EBN hyperspectral image were extracted, and these spectra were substituted in the calibration models to predict the PC, CC and SAC of each pixel in the EBN image, so the visual distribution maps of PC, CC and SAC on the whole EBN were obtained. It is the first time to show the distribution tendency of PC, CC and SAC on the whole EBN sample. [ABSTRACT FROM AUTHOR]

Novel colorimetric films were developed for real-time monitoring of fish freshness based on starch/polyvinyl alcohol (SPVA) incorporated with roselle ( Hibiseus sabdariffa L.) anthocyanins (RACNs). Firstly, RACNs were extracted from roselle dehydrated calyxes. Secondly, SPVA aqueous solution was obtained with a mass rate of 2:1 (starch/PVA). Thirdly, the colorimetric films were fabricated by immobilizing 30, 60 and 120 mg RACNs/100 g starch into SPVA matrix with casting/solvent evaporation method. FTIR spectra of the colorimetric films showed that RACNs were successfully immobilized into the SPVA matrix. X-ray diffraction spectra and SEM micrographs indicated that the crystallinity of PVA was reduced during the film-forming process and the compatibility between starch and PVA was improved, owing to the presence of RACNs. The incorporation of RACNs led to a decrease of water content and tensile strength and an increase of elongation at break of the colorimetric films compared with the SPVA film. The color stability test showed that the colorimetric films were stable at refrigeration temperature and room temperature up to 14 days with relative color changes below than 5%. The colorimetric films with lower content of RACNs were found more sensitive towards ammonia. An application trial was conducted to monitor the freshness of silver carp ( Hypophthalmichthys molitrix ) at refrigeration temperature. The colorimetric films presented visible color changes over time due to a variety of basic volatile amines known as total volatile basic nitrogen (TVB-N). Hence, these colorimetric films can be used to monitor the real-time fish freshness for intelligent packaging. [ABSTRACT FROM AUTHOR]

Heavy metals accumulating in the human body produce physiological toxicity by interfering with the transport of human proteins and enzymes. Heavy metals detection is significant for food safety assurance. This review focuses on recent advances of heavy metals detection of food and agricultural products by surface-enhanced Raman spectroscopy (SERS). The article covers the SERS basic principles and advances in heavy metals detection, including mercury, arsenic, cadmium, lead, chromium among others. Insights in the potential of combining chemometrics and multivariate analysis with SERS and the exploration of novel SERS substrate platforms from both macro and micro scale are discussed. Finally, future application of SERS in heavy metal detection are prospected. SERS is a powerful and promising technique offering the advantages of simple sampling, rapid data collection and non-invasiveness. The findings of this study can allow better understanding of the heavy metals' occurrence and the possibility of its detection using SERS. [ABSTRACT FROM AUTHOR]

The development of effective methods for tracking cancer cells is of significant importance in the early diagnosis and treatment of tumor diseases. Compared with the developed techniques, the electrochemical assay has shown considerable potential for monitoring glycan expression on the cell surface using nondestructive means. However, the application expansion of the electrochemical strategy is strongly impeded owing to its dependence on electroactive species. In this study, a competitive electrochemical strategy was reported for monitoring cancer cells based on mannose (a typical glycan) as a clinical biomarker. Herein, functionalized carbon nanotubes were used to load the thiomannosyl dimer, and thionine-interlinking signal probes were designed for competitive recognition. After effective competition between cancer cells and the anchored mannose, a decreased current was obtained as the cell concentration increased. Under optimal conditions, the proposed biosensor exhibited attractive performance for cancer cell analysis with a detection limit as low as 20 cells per mL for QGY-7701 and 35 cells per mL for QGY-7703, facilitating great promise for the sensitive detection of cancer cells and thus showing potential applications in cancer diagnosis. [ABSTRACT FROM AUTHOR]

Precise earthquake locations and InSAR (Interferometric Synthetic Aperture Radar) deformation observation are the major methods to understand the earthquake occurrence and disaster-causing process. This paper proposes a processing framework for analyzing strong earthquake mechanisms from one-dimensional velocity inversion to precise earthquake locations combined with InSAR deformation observation, and discusses earthquake-generating fault and dynamic mechanisms of tectonic deformation. We analyzed the Menyuan Ms 6.9 earthquake in 2022 and discuss the historical seismic activities and corresponding stress adjustment processes in the research region. To analyze and study the seismogenic structure and mechanism of the earthquake, we investigated the spatial and temporal distribution characteristics of the Menyuan earthquake sequence and analyzed the InSAR coseismic deformation field. We obtained the precise locations of the main shock and aftershocks and the coseismic InSAR deformation field of the main shock. It was confirmed that the Ms 6.9 earthquake was a shallow sinistral strike-slip earthquake, which led to the sequential activation of the Tuolaishan and Lenglongling faults. The main seismogenic fault of the mainshock was the northwestern end of the Lenglongling fault, and the earthquake rupture was segmented. It can be inferred that the earthquake was a stress-adjusted event triggered in the Qilian-Haiyuan tectonic belt caused by the northeasterly push of the Qinghai-Tibet Plateau. The risk of moderate to high earthquakes in the region remains high in the future, requiring enhanced seismic observations. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present a practical hybrid-power method for wireless chemical sensor of radio-frequency identification. Radio-frequency carrier is divided into dual-direction signal chain and single-direction power chain where 3-W wireless power transfer with ∼71% efficiency is possible. This feature is further enhanced by introducing a power management unit (PMU) coupled to a super capacitor. The hybrid of wireless power transfer and self-powered PMU provides a high-power window and a low-EMI window as long as 120 s. They contribute to powerful operations and high-performance measurements. A wireless electrochemical platform and a screen-printed electrode module are prepared to validate the proposed method. The electrode module is modified with multiple materials for pH sensing and stripping determinations of Cd(II) and Pb(II). The proposed method is evaluated by different means as scanning electron microscope, electrical measurement, cyclic voltammetry and stripping technique. Furthermore, it is used for natural water monitoring, and shows good stabilities and satisfying analytical properties in a 7-day period. [ABSTRACT FROM AUTHOR]

A new heuristic and parallel simulated annealing algorithm was proposed for variable selection in near-infrared spectroscopy analysis. The algorithm employs a parallel mechanism to enhance the search efficiency, a heuristic mechanism to generate high-quality candidate solutions, and the concept of Metropolis criterion to estimate accuracy of the candidate solutions. Several near-infrared datasets have been evaluated under the proposed new algorithm, with partial least squares leading to improved analytical figures of merit upon wavelength selection. Improved robust and predictive regression models were obtained by the new algorithm. The method could also be helpful in other chemometric activities such as classification or quantitative structure-activity relationship problems. [ABSTRACT FROM AUTHOR]

Salmonella enteritidis (SE) is an important factor causing foodborne disease, and electrochemical sensors have drawn much attention for SE prevention and detection due to their many advantages. A renewable electrochemical sensor using specially designed locked nucleic acids (LNA) as linkers for the detection of SE was proposed to improve the reusability and reproducibility of biosensors. One end of the LNA was designed as an anchor to attach to modified electrodes through the sulfhydryl group; the other end was used to match with a short segment of SE aptamers, which will allow for the convenient renewal of occupied aptamers by raising the temperature. Results revealed that the manufactured biosensor had good stability, reproducibility, and selectivity in addition to a linear range of 6 × 101–6 × 105 CFU/mL and a limit of detection (LOD) of 20.704 CFU/mL. The recovery rate of SE for the real sample varied from 98.84% to 134.82% without exceeding 16.27% in the relative standard deviation (RSD). The proposed biosensor appears to be a promising tool for foodborne pathogen detection. [ABSTRACT FROM AUTHOR]

Understanding the three‐dimensional structure, segmentation, and kinematics of complex fault systems is essential to assessing the size of potential earthquakes and related seismic hazards. The Danghe Nan Shan thrust, a major splay of the Altyn Tagh fault (ATF) in north Tibet, is one of these complex fault junctions. Near the town of Subei, the western Danghe Nan Shan thrust composes two left‐stepping faults outlined by fault scarps in front of folded and uplifted alluvial fans and terraces. Age constraints and 2D reconstructions of the accumulated slip above a transient base level of four terraces standing 7–60 m above the present stream bed yield shortening and vertical uplift rates of 0.5 ± 0.1 and 1.1 ± 0.3 mm/yr, respectively, over the last 130 ka on the southern thrust. Along the northern thrust, vertical terrace offsets of 1.5–3.6 m and horizontal slip of 4.5 m documented in a paleoseismological trench occurred after 12 ± 4 ka, constraining coeval rates of 0.3 ± 0.1 mm/yr for uplift and shortening. Overall, 1.4 ± 0.4 mm/yr terrace uplift and 0.8 ± 0.2 mm/yr shortening rates are determined, in agreement with late Miocene long‐term exhumation rate estimates. Our fault mapping and geomorphic and structural observations imply that the western Danghe Nan Shan thrust accommodates slip transfer from the ATF to the west to thrusting and shortening farther east in the Qilian Shan region. Considering the scarp sizes, their lateral extent, the geometry of the faults at depth, and their slip‐rate, we suggest the possible occurrence of Mw 7+ earthquakes near Subei. Plain Language Summary: How faults slip is essential to understanding continental deformation and seismic hazards. In the western Qilian Shan region, the Danghe Nan Shan is one of the largest ranges bounded by active thrust faults. West and south of Subei, these thrusts can be followed for several kilometers along meter‐high scarps and folded terraces. Quantifying the cumulative deformation of the folded and uplifted terraces and fans enables to constrain shortening rates of about 1 mm/yr over the last 130 ka. Evidence from surface geomorphology and sub‐surface trenching across the faults indicates the occurrence of large magnitude potentially up to Mw 7 seismic events in the last 16 ka. Integrating age‐controlled cumulative geological observations with field‐documented co‐seismic deformation increases the knowledge of slip rate and co‐seismic displacement for seismic hazards. Key Points: Combined cosmogenic nuclides, optically stimulated luminescence, and 14C dating methods constrain the deposition age of four folded inset terraces over the last 130 kaThe shortening rate of 0.8 ± 0.2 mm/yr across the western Danghe Nan Shan thrusts is coeval with decreasing left‐slip along the Altyn Tagh faultConcurrent rupture of thrusts and strike‐slip fault strands could result in a Mw 7+ earthquake southwest of Subei town [ABSTRACT FROM AUTHOR]

A sodium alginate (SA) film incorporated with Saccharomyces cerevisiae (SE) and sucrose (SU) was fabricated to control the quality and pericarp browning of longan. The SE with satisfactory glutathione production was selected as the antioxidant agent. The scanning electron microscopy (SEM) results revealed that the SU-rich SA film could be used as an effective carrier to protect the cell integrity of SE. The FTIR and mechanical property results indicated that the SA-SE film with the incorporation of SU has good flexibility due to the existence of hydrogen bonds. Notably, the cell viability of the SE was significantly improved with the addition of SU, which positively affects the antioxidant property of the film during the storage period. Finally, the SA-SE-3.0%SU films obviously improved the quality and pericarp browning of longan. The SA-based film incorporated with SU and SE may be established as a novel antioxidant fruit packaging material. [Display omitted] • S. cerevisiae with good glutathione production was selected as the antioxidant agent. • Active films made from sodium alginate (SA), sucrose and S. cerevisiae were developed. • Sucrose (SU) (3.0 % ∼ 6.0 %) significantly improved the mechanical property of the films. • The addition of S. cerevisiae (SE) enhanced the antioxidant property of the films. • SA-SE films with 3.0 % ∼ 6.0 % SU improved the quality and pericarp browning of longan. [ABSTRACT FROM AUTHOR]

The bilayer anti-ultraviolet preservation films were developed successfully by incorporating the cinnamon essential oil (CEO) to chitosan (CH) as the bioactive layer, and incorporating the TiO 2 to sodium alginate (SA) as the protective layer. The addition of CEO improved the antibacterial and antioxidant properties of the films. The addition of TiO 2 enhanced the bioactive retention property of the films. Remarkably, CS-0.6 film had better water vapor permeability (WVP) and mechanical properties, but CS-1.2 film had better antioxidant and antibacterial properties. After 10 d of storage, the CS-0.6 group of mangoes maintained the highest firmness of 17.62 ± 0.85 N and the highest total phenol content of 254.40 ± 4.14 mg/100 g. It also had the lowest lipoxygenase activity of 5.00 ± 1.66 10−3 U/kg. The obtained research results revealed that the developed CH/SA based bilayer film incorporated with CEO and TiO 2 could be used as a multifunctional packaging material to maintain the freshness of harvested mangoes. [Display omitted] • Chitosan/sodium alginate-TiO 2 based (CS) bilayer films were developed. • Cinnamon essential oil was used as antioxidant and antibacterial agent. • TiO 2 enhanced the UV–Vis blocking and bioactive retention properties of the films. • CS coating could effectively maintain the quality of the postharvest mangoes. [ABSTRACT FROM AUTHOR]

This study evaluated the presence of aflatoxin B1 in five different animal feeds collected from manufacturers, suppliers and consumers and its possible reduction by heating at 100°C for 180 min. A total of 160 animal feed samples were collected and analyzed by using lateral flow immunoassay method. The results revealed that all animal feeds analyzed were positive for aflatoxin B1 with 91% samples containing high concentrations ranging from 24.00 to 76.23 ng/g above the international allowable standard for animal feeds (20 ng/g). Maize bran (76 ng/g) and sunflower cake (63 ng/g) had higher aflatoxin B1 concentrations, correlating with higher moisture content. Upon heating the feeds, aflatoxin B1 was reduced to a concentration ranging from 2.24 to 9.78 ng/g (<20 ng/g). Our study suggests high potential health problems to animals and humans from aflatoxins requiring proper heating and frequent monitoring of the animal feeds for aflatoxin B1. [ABSTRACT FROM AUTHOR]

Simple Summary: The Egyptian honeybee (Apis mellifera lamarckii) is one of the honeybee subspecies known for centuries since the ancient Egypt civilization. The subspecies of the Egyptian honeybee is distinguished by certain traits of appearance and behavior that were well-adapted to the environment and unique in a way that it is resistant to bee diseases, such as the Varroa disease. The subspecies is different than those found in Europe and is native to southern Egypt. Therefore, a special care should be paid to the vulnerable A. m. lamarckii subspecies and greater knowledge about the risk factors as well as conservation techniques will protect these bees. Additionally, more qualitative and quantitative measures will be taken to obtain deep insights into the A. m. lamarckii products' chemical profile and biological characters. Egypt has an ongoing long history with beekeeping, which started with the ancient Egyptians making various reliefs and inscriptions of beekeeping on their tombs and temples. The Egyptian honeybee (Apis mellifera lamarckii) is an authentic Egyptian honeybee subspecies utilized in apiculture. A. m. lamarckii is a distinct honeybee subspecies that has a particular body color, size, and high levels of hygienic behavior. Additionally, it has distinctive characteristics; including the presence of the half-queens, an excessive number of swarm cells, high adaptability to climatic conditions, good resistance to specific bee diseases, including the Varro disorder, and continuous breeding during the whole year despite low productivity, using very little propolis, and tending to abscond readily. This review discusses the history of beekeeping in Egypt and its current situation in addition to its morphology, genetic analysis, and distinctive characters, and the defensive behaviors of native A. m. lamarckii subspecies. [ABSTRACT FROM AUTHOR]

Cardiotonic steroids (CTS) were first documented by ancient Egyptians more than 3000 years ago. Cardiotonic steroids are a group of steroid hormones that circulate in the blood of amphibians and toads and can also be extracted from natural products such as plants, herbs, and marines. It is well known that cardiotonic steroids reveal effects against congestive heart failure and atrial fibrillation; therefore, the term "cardiotonic" has been coined. Cardiotonic steroids are divided into two distinct groups: cardenolides (plant-derived) and bufadienolides (mainly of animal origin). Cardenolides have an unsaturated five-membered lactone ring attached to the steroid nucleus at position 17; bufadienolides have a doubly unsaturated six-membered lactone ring. Cancer is a leading cause of mortality in humans all over the world. In 2040, the global cancer load is expected to be 28.4 million cases, which would be a 47% increase from 2020. Moreover, viruses and inflammations also have a very nebative impact on human health and lead to mortality. In the current review, we focus on the chemistry, antiviral and anti-cancer activities of cardiotonic steroids from the naturally derived (toads) venom to combat these chronic devastating health problems. The databases of different research engines (Google Scholar, PubMed, Science Direct, and Sci-Finder) were screened using different combinations of the following terms: "cardiotonic steroids", "anti-inflammatory", "antiviral", "anticancer", "toad venom", "bufadienolides", and "poison chemical composition". Various cardiotonic steroids were isolated from diverse toad species and exhibited superior anti-inflammatory, anticancer, and antiviral activities in in vivo and in vitro models such as marinobufagenin, gammabufotalin, resibufogenin, and bufalin. These steroids are especially difficult to identify. However, several compounds and their bioactivities were identified by using different molecular and biotechnological techniques. Biotechnology is a new tool to fully or partially generate upscaled quantities of natural products, which are otherwise only available at trace amounts in organisms. [ABSTRACT FROM AUTHOR]

Summary: The present study investigated the effects of dry‐ageing time on physicochemical quality and protein properties of porcine longissimus lumborum within 48 h of postmortem ageing. Results showed that appropriately prolonged dry‐ageing time (24 and 36 h) had a positive effect on the tenderness, water‐holding capacity, thermal stability and gel properties of meat, as evident from the decrease of shear force, dripping loss, cooking loss, T2 relaxation time, enthalpy value and the increase in storage and loss modulus. Nevertheless, the excessive extension of ageing (48 h) increased the degree of protein oxidation and degradation by maintaining the lowest total sulfhydryl but the highest carbonyl content, and producing more small molecular weight protein chains (35.4, 20 and 19.6 KDa). Chemometric analysis further clarified the appropriate ageing time of desirable meat. In conclusion, dry ageing 24 and 36 h were suggested as the reasonable postmortem ageing time for porcine longissimus lumborum in China. [ABSTRACT FROM AUTHOR]

A novel microfluidic metal grating integrated terahertz sensor has been designed, which is composed of a metal microstructure array-dielectric layer-metal layer, where the dielectric layer is the microfluidic channel carrying the analyte. By adjusting the structural parameters of the metal grating sensor, a highly confined electromagnetic field can be obtained in the microfluidic channel, thereby significantly enhancing the interaction between the analyte and the terahertz wave and improving the terahertz detection sensitivity. The metal grating described in this paper is composed of an array of square holes, which is manufactured using laser micromachining technology, so that the measurement method is simplified and improved. The results show that the addition of different concentrations of carbendazim solution resulted in a redshift of the overall spectrum, with the highest sensitivity reaching 8.773 GHz/mg L−1, which is about eight times more sensitive than the traditional terahertz transmission sensor. The relative error of using this method to determine carbendazim levels in orange juice samples was less than 5.3%. The terahertz time-domain spectroscopy technology combined with the metal grating integrated microfluidic sensor can improve the sensitivity of sample detection and realize the rapid detection and analysis of trace elements. [ABSTRACT FROM AUTHOR]

• A novel fluorescent sensor for the detection of E. coli O157:H7 was constructed. • The fluorescent sensor was able to detect E. coli O157:H7 quickly and sensitively. • Design of the sensor based on the fluorescence resonance energy transfer principle. • The sensor has a high potential for real-world sample detection. The combination of carbon dots (CDs) with covalent organic frameworks (COFs) was used to design an innovative sensor based on fluorescence resonance energy transfer (FRET) for the detection of Escherichia coli O157:H7 (E. coli O157:H7) in food samples. Carbon dots were used as fluorescence donors, covalent organic frameworks as fluorescence acceptors. The antibody (Ab) specific to E. coli O157:H7 was used to form a CD-Ab-COF immunosensor by linking CDs and COFs. The antibody was specifically bound with E. coli O157:H7, which caused the connection between CDs and COFs to be interrupted, and the carbon dots exhibited fluorescence restoration. The sensor exhibited a linear detection range spanning from 0 to 106 CFU/mL, with the limit of detection (LOD) of 7 CFU/mL. The analytical performance of the developed immunosensor was evaluated using spiked food samples with different concentrations of E. coli O157:H7, validating the capability of assessing risks in food testing. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi-channel SERS-based LFIA strip for simultaneous detection of AFB1 and ZEN. • Magnetic Fe 3 O 4 @PEI/AuMBA@Ag-MBA as the active SERS tags. • Magnetic enrichment significantly increased the sensitivity. • High specificity and satisfactory recoveries for AFB1 and ZEN. • Short detection time (20 min) suitable for on-site detection. Aflatoxin B1 (AFB1) and zearalenone (ZEN) are two mycotoxins that often co-occur in corn. A surface-enhanced Raman scattering-based lateral flow immunoassay (SERS-LFIA) that can simultaneously detect AFB1 and ZEN in corn samples was developed employing the core-interlayer-satellite magnetic nanocomposites (Fe 3 O 4 @PEI/AuMBA@AgMBA) as dual-functional SERS tags. Under the optimal conditions, the detection ranges of AFB1 and ZEN in corn samples were 0.1–10 μg/kg and 4–400 μg/kg, respectively. Moreover, the test results for two mycotoxins in contaminated corn samples employing the suggested SERS-LFIA was in line with those of the HPLC technique. In view of its satisfactory sensitivity, accuracy, precision and short testing time (20 min), the developed system has a promising application prospect in the on-site simultaneous detection of AFB1 and ZEN. [ABSTRACT FROM AUTHOR]

Modifying proteins to enhance their affinity for polyphenols is essential for developing a practical and efficient delivery system that promotes the synergistic effects of bioactive substances. The study investigated the nanoparticle complexation in both pure soy protein isolate (SPI) or SPI modified by ultrasonic combined heat treatment (UHSPI) with varying concentrations of curcumin/catechin (CU/CA) complex, and its effects on the functionality, structure and conformational changes of protein-polyphenol nanocomplexes. Additionally, the intermolecular interaction and co-delivery mechanisms of nanocomplexes were analyzed. Results showed that the physical modification process (28/40 kHz, 90 °C, 15 min) and a rational concentration of CU/CA (0.6 mg/mL) improve the encapsulation efficiency of polyphenols by SPI (up to 77% for curcumin, and 93% for catechin), resulting in a higher DPPH and ABTS scavenging capacity, along with the highest emulsification activity index, as well as enhanced storage stability and thermal stability. The interaction between UHSPI and CU/CA disrupted the protein's secondary structure and exposed more hydrophobic residues to a hydrophilic environment, and exhibited stronger fluorescence quenching. Molecular docking analysis revealed that protein-polyphenol interactions primarily relied on hydrogen bonds and hydrophobic interactions, and 11S subunits exhibited higher affinity with CU/CA. FTIR, fluorescence spectra, and XRD further confirmed the enhanced interaction ability between UHSPI and CU/CA, resulting in the formation of a more stable nanocomplex. Overall, the modified SPI effectively facilitates the co-delivery of an appropriate concentration of curcumin/catechin complex. [Display omitted] • Modified SPI effectively facilitates the co-delivery of curcumin/catechin (CU/CA) complex. • The interaction of UHSPI and CU/CA exhibited stronger fluorescence quenching. • Hydrogen bonds and hydrophobic interactions played major roles in binding process. • Appropriate concentration of CU/CA significantly enhances the stability of the nanocomplexes. [ABSTRACT FROM AUTHOR]

This work aims to develop a biodegradable film with enhanced mechanical, water-barrier, and antimicrobial characteristics for the preservation of cherry tomatoes. Here, a persimmon pectin/ovalbumin (PN/OVA) stabilized-neem essential oil Pickering emulsion (NOPE) was added into the gelatin/sodium alginate-based blend matrix (GS). Even the biodegradability and transmittance of NOPE-rich film were decreased as compared to the control film, its flexibility, oxygen-barrier, and water-barrier performances significantly (P < 0.05) increased by 45.23 %, 32.32 %, and 37.02 %, respectively. The NOPE-loaded films destroyed the hyphal structure and reduced spore germination of Botrytis cinerea through slow-releasing neem essential oil (NO), in turn inhibiting the growth of B. cinerea. Finally, the prepared films were applied for cherry tomato preservation. Compared with the control, 2.0 wt%-loaded GS films greatly reduced the weight loss and disease incidence of cherry tomatoes by 57.33 and 72.4 %, respectively, owing to their excellent water resistance and slow-released properties. Thus, the addition of 2.0 wt% NOPE into GS film is of particular interest in the design of active biodegradable packaging films for fruit preservation. [Display omitted] • Polymer blend films based on gelatin and sodium alginate were developed successfully. • Neem essential oil Pickering emulsion was stabilized by persimmon pectin/ovalbumin. • Pickering emulsion improved the flexibility and release properties of the film. • The film inhibited the growth of B. cinerea by destroying the hyphal structure. • The film controlled the postharvest quality and gray mold in cherry tomatoes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Argon plasma is more effective in deactivating LMR lipolytic enzymes. • Starch powder is more susceptible to plasma than intact counterparts in grains. • Heightened etching effects observed with argon plasma in comparison to air plasma. • The excited argon species are insufficiently reactive to initiate lipid oxidation. This study investigated the effectiveness of cold-plasma treatment using air and argon as input gas on deactivation of lipolytic enzymes in lightly-milled-rice (LMR). The results showed no significant inactivation in lipase and lipoxygenase using air-plasma. However, using argon as input gas, the residual activities of lipase and lipoxygenase were reduced to 64.51 % and 29.15 % of initial levels, respectively. Argon plasma treatment resulted in more substantial augmentation in peak and breakdown viscosities of LMR starch, suggesting an enhancement in palatability of cooked LMR with increased stickiness and decreased hardness. In contrast to the decrease in volatile compounds in LMR following argon plasma treatment, the concentrations of several prevalent aroma compounds, including 1-hexanol, 1-hexanal, and 2-pentylfuran, exhibited significant increments, reaching 1489.70 ng/g, 3312.10 ng/g, and 58.80 ng/g, respectively. These findings suggest the potential for enhancing various facets of the commercial qualities of LMR by utilizing different input gases during plasma treatment. [ABSTRACT FROM AUTHOR]

• A bio-friendly corn starch (CS)/carbon dots (CDs) packaging film developed. • CDs imparted excellent oxidation resistance and antimicrobial capacity to the film. • The DPPH radical scavenging rate of CDs reached 92.77%. • The antimicrobial activity of CS/CDs film was increased to 99.9%. Packaging plays an important role in protecting food from environmental impacts. However, traditional petroleum-based packaging has difficulty in meeting the antimicrobial and antioxidant requirements of prepared foods. This study introduced carbon dots (CDs), prepared by using carrot as a precursor, into corn starch (CS) to construct a bio-friendly composite film with high freshness retention properties. The scavenging of DPPH radicals reached 92.77 % at a CDs concentration of 512 µg/mL, and the antimicrobial activity of CS/5% CDs against Escherichia coli and Staphylococcus aureus was increased to 99.9 %. Notably, the homogeneous doping of CDs creates a dense surface and high carbon content inside the film, which promotes the elasticity and thermal stability of the composite film. Finally, we encapsulated deep-fried meatballs in CS-CDs films. The results showed that the CS-CDs films effectively protected the quality of deep-fried meatballs, and have excellent potential for application in food preservation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Date seed polyphenols were tabulated in commercial pills. • Pill's polyphenols shielded BSA versus glycoxidation via different mechanisms. • Pill's polyphenols dose-dependently inhibited formation of advanced glycation end-products. • Pill's polyphenols trapped intermediated dicarbonyls and formed some new adducts. • Pill's polyphenols declined BSA-glucose binding and structurally blocked glycoxidation sites. We aimed at tabulating and characterizing a flavan-3-ol isolated from date seeds into date seed pills (DSP) as a commercial healthcare pill, and deeply studying their anti-glycoxidation impacts on bovine serum albumin using multi-dimensional approaches SDS-PAGE/NBT, UPLC-ESI-Q-TOF-MS, antiradical via Fenton-type reaction, multispectral, and molecular docking. Results showed that DSP were successfully tabulated (an encapsulation efficiency of 98.78 %) with high antioxidant values via noncovalently binding with whey proteins supported by FTIR and lib-dock results. DSP dose-dependently decayed fluorescent-AGEs by 16.77, 5.32, and 37.41 % in DSP500-BSA-G/MGO/GO models, respectively, later confirmed by SDS-PAGE and initial precursors mitigation results. The docking results confirmed that DSP could bind with glycoxidation sites of BSA-subunits, namely Lys431, Arg458, and Arg196 via H-bonds. DSP trapped both di-carbonyls and reduced CML-level, where new adducts such as epicatechin-mono/MGO-GO, were identified. 500 µg mL−1 DSP reduced OH-induced fluorescence intensity of AGEs by 43.32 % in BSA-G/Fe2+/H 2 O 2. Our results open a new direction for upcycling by-products as effective glycoxidation inhibitors in a type of healthcare pills in protein-rich models. [ABSTRACT FROM AUTHOR]

To develop natural and sustainable films with excellent physical, biological, and release properties for food packaging applications, a bilayer film based on guar gum/agar/sodium alginate /Litsea cubeba (Lour.) oil Pickering emulsion (LOPE)/titanium dioxide nanoparticles (TiO 2) was developed in this work. LOPE was herein prepared with hawthorn pectin/β-cyclodextrin complex particle as a stabilizer showed an average size of 0.961 μm and exhibited excellent physical stability. TiO 2 can greatly strengthen the tensile strength and barrier properties of the films by increasing the crystallinity. LOPE can not only significantly improve the inhibition effect of the films on the growth of Penicillium citreoviride (Inhibition percentage = 85.08%) by allowing the slow-release of volatile Litsea cubeba oil to destroy the mycelial structure, also significantly increase the elongation at break of the film by 57.05%. Constructing a bilayer system containing LOPE and TiO 2 was a desirable strategy for enhancing the properties of the films. As a proof of concept, cooked rice was utilized as experimental samples to investigate the impact of the film with TiO 2 /LOPE. Compared with the control, the TiO 2 /LOPE-rich bilayer film greatly reduced the total viable counts in cooked rice stored at 4℃ by 50.05%. This innovative film offers a cost-effective solution to effectively improve the quality and reduce mold infection in food. [Display omitted] • Litsea cubeba oil-loaded Pickering emulsion (LOPE) was prepared in this work. • LOPE and TiO 2 were successfully added to the AG/SA-based bilayer film. • LOPE improved the antifungal property of the film through slow-release of volatile LO. • TiO 2 enhanced the tensile strength and barrier properties of the films. • Film with LOPE/TiO 2 has great potential in preservation technology for cooked rice. [ABSTRACT FROM AUTHOR]

The high volatilization of essential oil caused low antibacterial efficiency and poor preservation effect of food-active packaging. Herein, the active sustained-release microencapsulated inclusion was synthesized by using β-cyclodextrin (β-CD) as the wall material and CEO as the core material. The inclusion rate of β-CD@CEO was 83.08 %, the embedding efficiency was 86.80 %, and the oil yield was 12.65 %. Then different concentrations of the β-CD@CEO complex were encapsulated in the PVDF nanofibers by uniaxial electrospinning technique. All the WCA results of the nanofiber films were greater than 90°.The release behavior of the CEO into the film was consistent with the first-order kinetic model. Similarly, the film presented the inhibition zone against E. coli and S. aureus of 17.1 mm and 16.7 mm, respectively. And the cell viability rate of the developed films was more than 80 %. Finally, the PVDF nanofibrous film with β-CD@CEO (4.5 %) can be used for griskin preservation to prolong the shelf life for 2 days at 4 °C. Thus, the developed sustained-release packaging film with high hydrophobicity could be suitable for potential application in high-humidity environments. [Display omitted] • Both microencapsulation and electrospinning improved the encapsulation efficiency. • PVDF hydrophobicity polymer helped to improve the integrality of the packaging film. • The packaging film extended the shelf life of griskin by 2 days at 4 °C. [ABSTRACT FROM AUTHOR]

[Display omitted] • DNA tetrahedral scaffolds improved detection accuracy and stability of electrochemical sensors. • Bifunctional work electrode greatly simplified the manufacturing process of biosensors. • HPG with the function of signal amplification was introduced for further improving sensitivity. • LOD of 2.4 and 3.5 pg/mL for OTA and AFB1 are qualified for the reliable monitoring of mycotoxins. • Dual-modality strategy provides a simple and accurate means for monitoring mycotoxins. Herein, a bifunctional electrochemical biosensor based on the DNA tetrahedral scaffolds (TDNs) was proposed, OTA@TDNs and AFB1@TDNs were adopted for electrochemical signal output in response to OTA and AFB1 concentration, simultaneously. In order to increase the conductivity of the biosensor, highly porous gold (HPG) was loaded on electrode surface by pulse electrodeposition. Under optimal conditions, the P Fc displayed a linear range with AFB1 concentration between 0.05 ∼ 360 ng·mL−1 with the LOD of 3.5 pg·mL−1. And the P MB selective and sensitive responses to OTA are achieved with a linear range of 0.05 ∼ 420 ng·mL−1 and a LOD of 2.4 pg·mL−1. This biosensor has high sensitivity, selectivity and stability for OTA and AFB1 detection in peanut samples. The approach streamlines the experimental procedure, leading to significantly improve the detection efficiency of mycotoxins. Collectively, this method suggest a novel approach for the detection and monitoring of OTA and AFB1 in food sample. [ABSTRACT FROM AUTHOR]