The application of starch-based edible film in food preservation: a comprehensive review.

Using renewable resources for food packaging not only helps reduce our dependence on fossil fuels but also minimizes the environmental impact associated with traditional plastics. Starch has been a hot topic in the field of current research because of its low cost, wide source and good film forming property. However, a comprehensive review in this field is still lacking. Starch-based films offer a promising alternative for sustainable packaging in the food industry. The present paper covers various aspects such as raw material sources, modification methods, and film formation mechanisms. Understanding the physicochemical properties and potential commercial applications is crucial for bridging the gap between research and practical implementation. Finally, the application of starch-based films in the food industry is discussed in detail. Different modifications of starch can improve the mechanical and barrier properties of the films. The addition of active substances to starch-based films can endow them with more functions. Therefore, these factors should be better investigated and optimized in future studies to improve the physicochemical properties and functionality of starch-based films. In summary, this review provides comprehensive information and the latest research progress of starch-based films in the food industry.

Metabolites and metabolic pathway analysis of sulfadimidine in carp (Cyprinus carpio) based on UHPLC-Q-orbitrap HRMS.

Sulfadimidine (SM2) is an N-substituted derivative of p-aminobenzenesulfonyl structure. This study aimed to analyze the metabolism of SM2 in carp (Cyprinus carpio). The carps were fed with SM2 at a dose of 200 mg/(kg · bw) and then killed. The blood, muscle, liver, kidney, gill, other guts, and carp aquaculture water samples were collected. The UHPLC-Q-Exactive Plus Orbitrap-MS was adopted for determining the metabolites of SM2 in the aforementioned samples. Twelve metabolites, which were divided into metabolites in vivo and metabolites in vitro, were identified using Compound Discoverer software. The metabolic pathways in vivo of SM2 in carp included acetylation, hydroxylation, glucoside conjugation, glycine conjugation, carboxylation, glucuronide conjugation, reduction, and methylation. The metabolic pathways in vitro included oxidation and acetylation. This study clarified the metabolites and metabolic pathways of SM2 in carp and provided a reference for further pharmacodynamic evaluation and use in aquaculture.

The Antibacterial Activities and Effects of Baicalin on Ampicillin Resistance of MRSA and Stenotrophomonas maltophilia.

The development of novel antibacterial agents from plant sources is emerging as a successful strategy to combat antibiotic resistance in pathogens. In this study, we systemically investigated the antibacterial activity and underlying mechanisms of baicalin against methicillin-resistant Staphylococcus aureus (MRSA) and Stenotrophomonas maltophilia. Our results showed that baicalin effectively restrained bacterial proliferation, compromised the integrity of cellular membranes, increased membrane permeability, and triggered oxidative stress within bacteria. Transcriptome profiling revealed that baicalin disrupted numerous biological pathways related to antibiotic resistance, biofilm formation, cellular membrane permeability, bacterial virulence, and so on. Furthermore, baicalin demonstrated a synergistic antibacterial effect when combined with ampicillin against both MRSA and S. maltophilia. In conclusion, baicalin proves to be a potent antibacterial agent with significant potential for addressing the challenge of antibiotic resistance in pathogens.

Application of essential oils as slow-release antimicrobial agents in food preservation: Preparation strategies, release mechanisms and application cases.

Food spoilage caused by foodborne microorganisms will not only cause significant economic losses, but also the toxins produced by some microorganisms will also pose a serious threat to human health. Essential oil (EOs) has significant antimicrobial activity, but its application in the field of food preservation is limited because of its volatile, insoluble in water and sensitive to light and heat. Therefore, in order to solve these problems effectively, this paper first analyzed the antibacterial effect of EOs as an antimicrobial agent on foodborne bacteria and its mechanism. Then, the application strategies of EOs as a sustained-release antimicrobial agent in food preservation were reviewed. On this basis, the release mechanism and application cases of EOs in different antibacterial composites were analyzed. The purpose of this paper is to provide technical support and solutions for the preparation of new antibacterial packaging materials based on plant active components to ensure food safety and reduce food waste.

Ionic liquids functionalized Fe3O4-based colorimetric biosensor for rapid determination of ochratoxin A.

A stainless steel mesh (SSM) with the feature of flexibility was employed as the colorimetric biosensor substrate, and aptamer was bond onto the surface of the SSM. Through the cross-linking of ionic liquids (ILs), AuPt nanoparticles were deposited  onto the surface of Fe3O4 material to obtain a magnetic nanozyme with high peroxidase catalytic activity and rapid color change. Through the competing interaction of OTA and cDNA with aptamer, AuPt@IL@Fe3O4 signal probe was separated to catalyze the 3,3',5,5'-tetramethylbenzidine/hydrogen peroxide (TMB/H2O2) system to observe the color by bare eye and record the absorbance at 652 nm using a UV-spectrophotometer. Through the study of the catalytic properties on the basis of the Michaelis equation, AuPt@IL@Fe3O4 nanozyme presented a Vmax of 3.85 × 10-8 M s-1 and Km of 0.01 mM. Under the optimized conditions, the linear range of the colorimetric biosensor towards OTA was 5-100 ng mL-1, and the detection limit was 0.078 ng mL-1. This biosensor was applied to beer and corn samples with recoveries of 70.4-102.6% and 93.3-104.7%, respectively. Results showed that this sensor is a portable, rapid, economical, sensitive visual sensing platform towards mycotoxin in real samples.

Broad-Spectrum Antibody-Based Immunochromatographic Strip Assay for Rapid Screening of Bisphenol A Diglycidyl Ether and Its Derivatives in Canned Foods.

Bisphenol A diglycidyl ether (BADGE) is widely present in the inner coating of metal food cans, from which it can migrate into food and generate harmful derivatives during storage, such as bisphenol A (2,3-dihydroxypropyl) glycidyl ether, bisphenol A (3-chloro-2-hydroxypropyl) glycidyl ether, and bisphenol A (3-chloro-2-hydroxypropyl) (2,3-dihydroxypropyl) glycidyl ether. Here, a gold-nanoparticle-based immunochromatographic strip assay based on a broad-spectrum polyclonal antibody was developed for the simultaneous detection of BADGE and its derivatives, which could be accomplished within 15 min. The quantitative analysis of the visualization results was performed using Adobe Photoshop CC 2021, and the detection limit, defined as the concentration causing 15% inhibition, was 0.97 ng/mL. The recoveries of BADGE and its derivatives at various spiking levels in canned food samples ranged from 79.86% to 93.81%. The detection results of the proposed immunochromatographic strip assay were validated via high-performance liquid chromatography, showing a good correlation coefficient (R2 = 0.9580).

Ensuring seafood safe to spoon: a brief review of biosensors for marine biotoxin monitoring.

With harmful algal blooms, marine food poisoning caused by marine biotoxins frequently occurs and is life-threatening if severe. However, the conventional detection methods of marine toxins have a few limitations: low sensitivity and high-cost. Therefore, it is necessary to establish a fast and sensitive on-site detection method for real seafood sample. Biosensors based on aptamers, antibodies, and cells have been applied in marine toxins monitoring. This review presents the classification and toxic effects of marine toxins, and recent biosensor for marine toxin detection. In addition, we have compared the superiority and limitation of these biosensors. Finally, challenges and opportunities of biosensors in food safety detection were discussed. Considering the excellent results achieved by the aptasensor in the field of detection, it seems ready to be put into practical applications.

An aptamer and flower-shaped AuPtRh nanoenzyme-based colorimetric biosensor for the detection of profenofos.

In this work, a simple, sensitive and selective colorimetric method was established for the detection of profenofos. Firstly, novel flower-shaped AuPtRh trimetallic nanospheres were synthesized via a simple one-pot method, and had outstanding peroxidase catalytic activity. AuPtRh nanospheres with a great specific surface area were linked with an aptamer via Au-S and Pt-S bonds to specifically recognize profenofos. A graphene oxide grafted stainless-steel mesh (SSM-GO) was prepared to be a carrier and the aptamer-AuPtRh was nonspecifically adsorbed on the surface of SSM-GO, which was to be the capture probe for the detection of profenofos in real samples. They were characterized and confirmed by transmission electron microscopy, atomic force microscopy, etc. Through the investigation of the catalytic performance on the basis of the Michaelis equation, the Vmax of AuPtRh nanospheres was 22.27 × 10-8 M s-1, and Km was 0.6632 mM, which indicated that the affinity of AuPtRh nanospheres was relatively higher than that of horseradish peroxidase and Au NPs. In the presence of profenofos, the aptamer-AuPtRh would specifically combine with profenofos, which would further detach from SSM-GO. Then, it was introduced into the 3,3',5,5'-tetramethylbenzidine/H2O2 (TMB/H2O2) system to form blue oxTMB. The linear range of this colorimetric biosensor was 1-300 ng L-1 and the limit of detection was 0.725 ng L-1. It also had good recovery and anti-interference ability in real samples, which provided a new strategy for the rapid detection of pesticides.

Pseudomonas laoshanensis sp. nov., isolated from peanut field soil.

A novel Gram-stain-negative, aerobic strain, designated Y22T, was isolated from peanut field soil in Laoshan Mountain in China. Cells of strain Y22T were rod-shaped and motile by a single flagellum. The strain was found to be oxidase- and catalase-positive. 16S rRNA gene sequence based on phylogenetic analysis indicated that strain Y22T belonged to the genus Pseudomonas, and showed the highest 16S rRNA gene sequence similarity of 99.0% to Pseudomonas pelagia JCM 15562T, followed by Pseudomonas salina JCM 19469T (98.4%), Pseudomonas sabulinigri JCM 14963T (97.9%), Pseudomonas bauzanensis CGMCC 1.9095T (97.6%) and Pseudomonas litoralis KCTC23093T (97.5%). The phylogenetic analysis based on multilocus sequence analyses with concatenated 16S rRNA, gyrB, rpoD and rpoB genes indicated that strain Y22T belonged to Pseudomonas pertucinogena lineage. The average nucleotide identity scores between strain Y22T and closely related species were 74.6-82.8%, and the Genome-to-Genome Distance Calculator scores were 16.4-44.9%. The predominant cellular fatty acids of strain Y22T were C18:1ω7c (29.6%), C17:0 cyclo (17.5%) and summed feature 3 (C16:1ω7c and/or C16:1ω6c) (17.4%). The genomic DNA G+C content was 57.9 mol%. On the basis of phenotypic characteristics, phylogenetic analyses and in silico DNA-DNA relatedness, a novel species, Pseudomonas laoshanensis sp. nov. is proposed. The type strain is Y22T (= JCM 32580T = KCTC 62385T = CGMCC 1.16552T).

Construction of an electrochemical sensor with graphene aerogel doped with ZrO2 nanoparticles and chitosan for the selective detection of luteolin.

A simple, fast and sensitive method for the detection of luteolin is proposed based on the chitosan/reduced graphene oxide aerogel with dispersed ZrO2 nanoparticles modified glassy carbon electrode (ZrO2/CS/rGOA-GCE) as an electrochemical sensor. The ZrO2/CS/rGOA composite was prepared by one pot synthesis from a mixture of GO, CS and zirconyl chloride octahydrate, and subsequently be freeze-dried. Scanning electron microscope images showed a typical thin, wrinkled and fluctuant morphology of graphene nanosheets and the polymerized CS and ZrO2 nanoparticles deposited on the surface of rGOA. Cyclic voltammetry and differential pulse voltammetry were used to measure the electrochemical response of ZrO2/CS/rGOA composite-based biosensor towards luteolin at the working potential window (-0.8-0.8 V). The improved performance of this biosensor was attributed to efficient electron transfer and large surface area of 3D rGOA, and high specific activity of Zr towards adjacent hydroxyl groups. Under optimized conditions, the analytical performance of this method towards luteolin was investigated with a detection limit of 1 nM and a linear range from 5 nM to 1000 nM.. Finally, the ZrO2/CS/rGOA-GCE electrochemical method coupled with solid phase extraction was used for the detection of luteolin in real samples. Recoveries of  spiked samples with different concentrations were in the range 78.6-103.3% with a relative RSD lower than 12.0%. Graphical abstract Schematic representation of the preparation of the ZrO2 nanoparticles and chitosan doped graphene aerogel modified electrode. The electrode was employed for the detection of luteolin coupled with the solid-phase extraction technique.

Research advances of DNA aptasensors for foodborne pathogen detection.

Aptamers, referring to single-stranded DNA or RNA molecules can specifically recognize and bind to their targets. Based on their excellent specificity, sensitivity, high affinity, and simplicity of modification, aptamers offer great potential for pathogen detection and biomolecular screening. This article reviews aptamer screening technologies and aptamer application technologies, including gold-nanoparticle lateral flow assays, fluorescence assays, electrochemical assays, colorimetric assays, and surface-enhanced Raman assays, in the detection of foodborne pathogens. Although notable progress (more rapid, sensitive, and accurate) has been achieved in the field, challenges and drawbacks in their applications still remain to be overcome.

Origin traceability of peanut kernels based on multi-element fingerprinting combined with multivariate data analysis.

BACKGROUND: Multi-elements have been widely used to identify the geographical origins of various agricultural products. The objective of this study was to investigate the feasibility of identifying the geographical origins of peanut kernels at different regional scales by using the multi-element fingerprinting technique. The concentrations of 20 elements [boron (B), magnesium (Mg), phosphorus (P), potassium (K), calcium (Ca), etc.] were determined in 135 peanut samples from Jilin Province, Jiangsu Province, and Shandong Province of China. Data obtained were processed by one-way analysis of variance (ANOVA), principal components analysis (PCA), k nearest neighbors (k-NN), linear discriminant analysis (LDA), and support vector machine (SVM). RESULTS: Peanut kernels from different regions had their own element fingerprints. The k-NN, LDA, and SVM were all suitable to predict peanut kernels according to their grown provinces with the total correct classification rates of 91.2%, 91.1%, and 91.1%, respectively. While SVM was the best to identify different grown cities of peanut kernels with the prediction accuracy of 91.3%, compared to 72.2% and 78.3% for k-NN and LDA, respectively. CONCLUSION: It was an effective method to identify producing areas of peanut kernels at different regional scales using multi-element fingerprinting combined with SVM to enhance regional capabilities for quality assurance and control. © 2020 Society of Chemical Industry.

Determination of the geographical origin of maize (Zea mays L.) using mineral element fingerprints.

BACKGROUND: Maize (Zea mays L.) is a staple cereal crop and feed crop throughout the world. In this article, a mineral element fingerprinting technique was applied to single out suitable element indicators to determine the geographical origin of maize. A total of 90 fresh maize samples were collected in 2107 from Jilin, Gansu, and Shandong provinces in China. The contents of 25 mineral elements in all maize samples were measured by inductively coupled plasma mass spectrometry (ICP-MS). The composition of mineral elements was analyzed by multivariate statistical analysis, including one-way analysis of variance (one-way ANOVA), principal component analysis (PCA), k-nearest neighbor (KNN) analysis, and stepwise linear discriminant analysis (SLDA). RESULTS: As compared by one-way ANOVA, the contents of 19 mineral elements in maize samples were significantly different among three provinces. Principal component analysis based on these 19 elements could obtain preliminary visual classification groups of maize samples. K-nearest neighbor analysis produced a total correct classification rate of 83.9% on the training set, and 82.2% on the prediction set. The SLDA model, based on eight indicative elements (Na, Cr, Rb, Sr, Mo, Cs, Ba, and Pb) obtained a total correct classification rate of 92.2% with cross-validation. CONCLUSION: The mineral element fingerprinting technique combined with multivariate statistical analysis could be a helpful method to identify the geographical origin of maize. © 2019 Society of Chemical Industry.

Novel subgenotype D11 of hepatitis B virus in NaPo County, Guangxi, bordering Vietnam.

Hepatitis B virus has been classified into 10 genotypes and 48 subgenotypes worldwide. We found previously, through polymerase chain reaction (PCR) amplification of a sample collected in 2011, that an HBsAg carrier was infected with two genotypes (B and D) of HBV. We carried out cloning, sequencing and phylogenetic analysis of the complete genomes and, for confirmation, analysed a sample collected from the same individual in 2018. Fifteen complete sequences were obtained from each sample. The carrier was infected in 2011 by genotypes B and D and by various recombinants, but only genotype D was present in 2018. The major and minor parents of the recombinants are genotypes B and D, respectively, although the recombination breakpoints vary among them. All 23 genotype D isolates form a cluster, branching out from other subgenotype D sequences and supported by a 100 % bootstrap value. Based on complete genome sequences, almost all of the estimated intragroup nucleotide divergence values between our isolates and HBV subgenotypes D1-D10 exceed 4 %. Compared to the other subgenotypes (D1-D10), 35 unique amino acids were present in our isolates. Our data provide evidence for a novel subgenotype, provisionally designated HBV subgenotype D11.

Asymptomatic hepatitis B carriers who were vaccinated at birth.

The long-term persistence of immunity following universal infant immunization against hepatitis B virus (HBV) and the need for a subsequent booster dose in adolescence remain under debate. With data derived from Long'an County, Guangxi, China, we reported previously that the prevalence of hepatitis B surface antigen (HBsAg) among adults born from 1987 to 1993 increases with age, although these individuals had received a first dose of the vaccine within 24 hours of birth. Here, we sought the source of transmission by comparison of genotypes among their family members using phylogenetic analysis of complete HBV S gene sequences. For comparison, we screened 2199 vaccinated individuals aged 5 to 17 in Cang Wu County and 1592 vaccinated individuals aged 3 to 7 in Ling Shan County in Guangxi for HBsAg carriers and investigate their family members. In total, 50 asymptomatic HBsAg carriers who were vaccinated at birth and 152 family members were analyzed. The results showed that 25% (95% CI: 6.0-44.0) of the HBsAg-positive children had not acquired their HBV infection from their mothers. This phenomenon showed a trend that increases with age. Antibody escape mutations were detected in 22.9% (95% CI: 11.0-34.8) of the isolates. In conclusion, a booster dose may be necessary for adolescence who were vaccinated at birth in highly endemic countries.

Locus 5p13.1 may be associated with the selection of cancer-related HBV core promoter mutations.

Background: The basal core promoter (BCP) double mutations (A1762T and G1764A) of hepatitis B virus (HBV) have been reported to be an aetiological factor of hepatocellular carcinoma (HCC). What distinguishes the subset of HBV carriers in whom these mutations are selected? Methods: A genome-wide association study (GWAS) was carried out on 218 asymptomatic HBsAg carriers infected with HBV with BCP double mutations and 191 controls infected with HBV with the wild type BCP. The highest ranking nucleotide polymorphisms (SNPs) were validated with other study subjects, 203 cases and 181 controls. The expression of the gene nearest a SNP found to be significant was examined using RT-PCR. Results: Forty-five candidate SNPs were identified in the GWAS. Three SNPs were found to be associated with the selection of HBV BCP double mutations in the replication stage, including rs7717457 at 5p13.1, rs670011 at 17q21.2, rs2071611 at 6p22.2. Especially, rs7717457 (P= 4.57×10-5 combined P) reached the potential GWAS significance level. The expression of gene complement component 7 (C7), nearest to SNP rs7717457, differed significantly between the case and control groups (t=2.045, P=0.04), suggesting that SNP rs7717457 was associated with the expression of its nearest gene. Conclusions: SNP rs7717457 is associated with the selection of HBV BCP double mutations, providing an important clue to understanding the mechanisms of oncogenesis of HBV BCP double mutations.

Draft genome of the peanut A-genome progenitor (Arachis duranensis) provides insights into geocarpy, oil biosynthesis, and allergens.

Peanut or groundnut (Arachis hypogaea L.), a legume of South American origin, has high seed oil content (45-56%) and is a staple crop in semiarid tropical and subtropical regions, partially because of drought tolerance conferred by its geocarpic reproductive strategy. We present a draft genome of the peanut A-genome progenitor, Arachis duranensis, and 50,324 protein-coding gene models. Patterns of gene duplication suggest the peanut lineage has been affected by at least three polyploidizations since the origin of eudicots. Resequencing of synthetic Arachis tetraploids reveals extensive gene conversion in only three seed-to-seed generations since their formation by human hands, indicating that this process begins virtually immediately following polyploid formation. Expansion of some specific gene families suggests roles in the unusual subterranean fructification of Arachis For example, the S1Fa-like transcription factor family has 126 Arachis members, in contrast to no more than five members in other examined plant species, and is more highly expressed in roots and etiolated seedlings than green leaves. The A. duranensis genome provides a major source of candidate genes for fructification, oil biosynthesis, and allergens, expanding knowledge of understudied areas of plant biology and human health impacts of plants, informing peanut genetic improvement and aiding deeper sequencing of Arachis diversity.

The suitability of rare earth elements for geographical traceability of tea leaves.

BACKGROUND: Rare earth elements (REEs) have been used for the identification of the geographical origins of an increasing number of foods. This study analyzed the effects of geographical origin, harvest season, variety, and their interactions on REEs in tea leaves to investigate whether REEs were suitable for geographical identification of tea leaves. Tea leaves of different varieties and the corresponding soils were collected in different seasons from different areas of China. The concentrations of 14 REEs in tea leaves and soils were determined, and then analyzed with one-way analysis of variance (ANOVA), multi-way ANOVA, correlation analysis, and linear discriminant analysis. RESULTS: All factors significantly affected the contents of REEs in tea leaves. The concentrations of REEs in tea leaves were related to those in provenance soils. However, the concentrations of most REEs in tea leaves were primarily affected by the harvest season. CONCLUSION: Seasonal variations should be considered when REE fingerprinting is applied for the identification of tea for authentication purposes. © 2019 Society of Chemical Industry.

High Prevalence of HBV Lamivudine-Resistant Mutations in HBV/HIV Co-Infected Patients on Antiretroviral Therapy in the Area with the Highest Prevalence of HIV/HBV Co-Infection in China.

OBJECTIVES: We aimed to determine the prevalence of hepatitis B virus (HBV) drug-resistant mutations in patients co- infected with HBV/human immunodeficiency virus (HIV), including both drug-naïve subjects and those who received antiretroviral therapy (ART) in Guangxi, where the prevalence of HIV/HBV co-infection is highest in China. METHODS: Two hundred and three subjects co-infected with HBV/HIV were recruited, including 123 drug-naïve patients (group 1) and 80 who received ART (group 2). The polymerase gene of HBV in the serum of all study subjects was analysed. RESULTS: The results showed that the prevalence of HBV drug-resistant mutations in group 2 (76.5%, 95% CI 56.3-96.7) was significantly higher than that in group 1 (1.4%, 95% CI -1.4 to 4.2; χ2 = 50.955, p < 0.05). The major pattern of lamivudine (3TC)-resistant mutations is L180M+M204I+L80I (35.7%). In total, 95% of subjects with resistant mutations had cross-resistance to telbivudine and entecavir. No putative tenofovir disoproxil fumarate (TDF) resistance change was found. Five subjects (6.5%) in group 2 had HBV viral loads over 10 × 106 copies/mL. Four of them had 3TC-resistant mutations. Multivariate analysis showed that ART was the only factor associated with the development of drug-resistant mutations. CONCLUSION: Treating HIV in HIV/HBV co-infection with antiretroviral agents may result in a very high prevalence of HBV 3TC-resistant mutations. TDF could not completely suppress HBV replication.

Efficient construction of C-N and C-S bonds in 2-iminothiazoles via cascade reaction of enaminones with potassium thiocyanate.

A novel and highly efficient protocol has been developed for the regioselective synthesis of 2-iminothiazole derivatives with potential biochemical interest by the reaction of enaminones, potassium thiocyanate (KSCN), and N-bromo succinimide (NBS) under mild conditions. The reaction proceeds via the formation of α-bromo enaminones as a versatile intermediate followed by thiocyanation/intramolecular cyclization in a one pot manner. The developed method is particularly attractive due to various advantages including operational simplicity, mild conditions, being catalyst free, and high bond-forming efficiency. The proposed protocol explores the synthetic routes of thiazoles by using various functional enaminones.