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Abstract: Oil oxidation is considered to involve the formation of free radicals. In this study, several major fatty acids in peanut oil have been investigated, and it showed that free radicals were mainly generated from the unsaturated fatty acids oleic acid and linoleic acid. Through a fitting analysis of the types of free radicals, they were identified as alkyl peroxy radicals (DMPO-•OOL), alkoxyl radicals (DMPO-•OL), alkyl radicals (DMPO-•L), and unknown radicals (DMPO-•X). In a comparison of two different heating temperatures, at 90 °C the electron spin resonance (ESR) spectrum was dominated by alkoxyl radicals (DMPO-•OL) and an unknown radical (hyperfine splitting constants of α N = 14.73 G and α H = 2.12 G, as befits a comprehensive carbon-centered radical). At 120 °C, the ESR spectrum was dominated by alkyl radicals (DMPO-•L). This study has indicated that ESR provides a powerful method for evaluating free radical generation in the oxidation of peanut oil. Highlights • Electron spin resonance (ESR) provided a powerful method to evaluate the free radicals in oxidation process of peanut oil. • Changes of free radicals from unsaturated fatty acids oleic acid and linoleic acid were studied. • Electron spin resonance (ESR) has potential to evaluate the oxidative stability of peanut oil. [ABSTRACT FROM AUTHOR]

Fusarium solani (CICC 2603) is one of the main postharvest spoilage strains of many fruits and vegetables. This research was to investigate the synergistic antifungal mechanism of thymol and salicylic acid (S TSA) on F. solani. Morphological observation showed that the cell structure and morphology changed seriously after S TSA treatment. Determination of F. solani stained cells with propidium iodide (PI) indicated that S TSA damaged the integrity of cell membrane, and the contribution of salicylic acid was greater than that of thymol. Meanwhile, the increase in the absorbance of 260 nm and 280 nm demonstrated that S TSA caused the leakage of cell contents severely, and the contribution of thymol was greater than that of salicylic acid. In addition, the decrease of ergosterol biosynthesis showed that S TSA interfered with membrane function of F. solani. Mitochondrial membrane potential (MMP) and enzymes activities of tricarboxylic acid (TCA) cycle experiments demonstrated that the mitochondrial function was seriously injured in F. solani. These results showed that S TSA inhibited the activity of F. solani more effectively than thymol or salicylic acid alone, by disrupting integrity and function of the cell membrane, causing leakage of the cell contents, meanwhile inhibiting function of the mitochondria, ultimately resulting in cell death. • The combination of thymol and salicylic acid (S TSA) had synergistic inhibition effect on F. solani. • S TSA treatment induced the disruption of cell membrane integrity and permeability. • S TSA treatment severely damage the morphology and function of mitochondria. • Thymol and salicylic acid played different role in synergistic antifungal effect. [ABSTRACT FROM AUTHOR]

The transformation of carbosulfan (CSN) in apples was investigated during oven-drying, microwave drying, and sun-drying. CSN transformed primarily into carbofuran (COA) during these drying processes. The conversion kinetics of CSN and COA was fitted by curve regression and mainly conformed to quadratic models (R2 = 0.70–0.97). Oven-drying promoted the transformation of CSN into COA. Microwave drying resulted in the highest scavenging capacity against CSN and COA (41%–100%). Moreover, a transformation mechanism was proposed on the basis of density functional theory (DFT) calculation. The COA originated from a series of chemical reactions involving hydroxyl substitution, cleavage, and oxidation; this result was further confirmed on the basis of molecular electrostatic potential (MEP) and molecular orbital theory. Furthermore, the toxicity and stability of CSN and COA were evaluated with the T.E.S.T. program. COA was less toxic than CSN to aquatic organisms but more toxic than CSN to rats. Therefore, COA production should be avoided during drying. Microwave drying was found to be the optimum choice for drying apples. • The effect of drying on CSN was analyzed. • The properties of pesticide molecules were analyzed. • The transformation pathway of CSN was proposed based on DFT calculations. • The toxicity of the CSN and transformation products were evaluated. [ABSTRACT FROM AUTHOR]

Traditional packaging has reached its limits in ensuring food quality and prolonging shelf life. In this study, we developed antifungal sachets containing essential oils (EOs) in microcapsules (ASEOs-CM) and evaluated their application potential in bread preservation. The results showed that the release of EOs from ASEOs-CM at 25 °C followed first-order kinetics. In addition, EOs-containing ASEOs-CM had strong inhibitory effects on microorganisms in vitro and effectively inhibited the growth of molds and yeasts on sliced bread. In the experimental group, the contents of eugenol and citral EOs on bread increased during storage. Breads in three different packages (LDPE, PP and HDPE) had a total shelf life of 13, 13, and 15 d, respectively, while control breads had a shelf life of 5 d. Sachets did not affect the sensory properties of bread. Therefore, the use of ASEOs-CM was an effective, safe, and sustainable preservation method for breads. • The sachets of compound essential oil containing microcapsules were developed. • The sachets has good antifungal activity. • The sachets has no effect on the sensory characteristics of bread. • The sachets can be used to extend the shelf life of baked products. [ABSTRACT FROM AUTHOR]

A green synthesis method for nanoscale silver using β-cyclodextrin as both reducing agent and stabilizer was developed. β-cyclodextrin was used not only as a reducing agent but also a stabilizing agent for nano-silver, and is also an excellent detection substrate due to its special structure (inner hydrophobic and outer hydrophilic ring structure). Then, the green synthesized silver nanoparticles were used as Surface-enhanced Raman spectroscopy (SERS) enhanced substrates to detect polycyclic aromatic hydrocarbons, such as: anthracene, pyrene, chrysene and triphenylene. The SERS substrate can be used for both quantitative detection of the four polycyclic aromatic hydrocarbons and qualitative identification of mixtures of these hydrocarbons. This synthesis method is simple and convenient, having great potential in simultaneous and rapid detection of environmental organic pollutants. Image 1 • A green synthesis method of nano silver surface reinforced substrate is introduced in this paper. • β-cyclodextrin could be used both as a reducing agent and as a stabilizer because of its unique structure. • The enhanced substrate synthesized by this method can be used for the detection of polycyclic aromatic hydrocarbons. [ABSTRACT FROM AUTHOR]

The synergistic effects of different essential oils can not only reduce their dosage and cost, but also improve their biological activity. The aim of this study was to evaluate the synergistic antifungal effect of eugenol and citral (S EC) on Penicillium roqueforti. Determination of reactive oxygen species (ROS) and malondialdehyde content indicated that S EC could induce membrane lipid peroxidation, and the contribution of citral was greater than that of eugenol. In addition, downregulation of the gene encoding an NADPH oxidase subunit indicated that the ROS burst induced by S EC was mediated by NADPH oxidase. Scanning electron microscope (SEM) and transmission electron microscope (TEM), propidium iodide treatment, DNA gel electrophoresis and cell leakage experiments showed that S EC destroyed the integrity of the cell membrane and internal structures, and degraded the cell contents, and the contribution of eugenol was greater than that of citral. These results showed that S EC inhibited the activity of P. roqueforti more effectively than eugenol or citral alone, by inducing membrane lipid peroxidation and promoting the ability of eugenol to destroy the cell membrane. The combined agents eventually caused leakage of the cell contents, and ultimately cell death. •The combination of eugenol and citral (S EC) had synergistic inhibition effect against P. roqueforti. •S EC treatment could significantly induce lipid peroxidation. •S EC treatment resulted in damaged the morphology of cells. •S EC treatment resulted in loss of plasma membrane integrity. [ABSTRACT FROM AUTHOR]

To control the spoilage of bread products and reduce the costs associated with preventing their spoilage, the synergistic antifungal effects of natural agents against the main bread spoilage fungi Penicillium roqueforti and Aspergillus niger were studied. After screening 66 groups antifungals using the checkerboard method, only one combination, i.e., that of eugenol and citral (S EC), showed synergistic effects against both the fungi. Their average minimal inhibitory concentrations (MICs) decreased significantly when they were present as a combination, i.e., by 3.40-fold, compared to the case when each agent was used separately. S EC inhibited the spore germination of both the fungi by more than 95% at 2 × MIC. At the same time, their mycelial growth was almost completely inhibited. The morphology of the mycelia was further observed by SEM. Serious wrinkles and deformations were found on the surface of the mycelia at 2 × MIC. Finally, the shelf life tests showed that treatment with S EC significantly prolonged the molding time of bread. These results showed that S EC may serve as a spoilage control measure and reduce the costs associated with preventing bread spoilage. • The combination of citral and eugenol (S EC) had a synergistic effect on both mold. • S EC effectively inhibited spore germination and mycelial growth. • S EC could significantly prolong the shelf life of bread. [ABSTRACT FROM AUTHOR]

To prevent the spoilage of vegetables in food processing, hexanal, a quorum-sensing (QS) inhibitor, was first used to inhibit the formation of Erwinia carotovora and Pseudomonas fluorescens biofilms. Their growth curves were not markedly inhibited by hexanal below the minimum inhibitory concentration (MIC), but the biofilm formation could be inhibited. Motility, exopolysaccharide production, and biofilm formation of E. carotovora and P. fluorescens were significantly inhibited by hexanal at sub-MICs (P < 0.05). There was a positive dose-dependent relationship (r = 0.8167–0.9998) between the inhibition ratio and concentrations of hexanal during the critical biofilm-formation stage (1–3 d), as well as a negative relationship (r = −0.8168 to −0.9998) between the inhibition ratio and culture time. The biomass, as well as average and maximum of biofilm thicknesses, decreased significantly (P < 0.05) relative to those of the control group. Luminescence, which represents the AI-2 molecule, decreased significantly with the increase in hexanal concentration (P < 0.05), indicating that inhibition of motility, exopolysaccharide production, and biofilm formation of E. carotovora and P. fluorescens was related to the decrease in the autoinducer AI-2. Therefore, hexanal could be developed as a new QS inhibitor for preventing decay of vegetables in the food industry. • Biofilm formation was inhibited with good dose-dependent under MIC. • Inhibition occurred significantly in the earlier stage of biofilm formation. • Hexanal inhibited biofilm formation due to the reduction of AI-2. [ABSTRACT FROM AUTHOR]

Abstract In order to explore the safety of bisphenol A (BPA) degradation in food packaging, the degradation effect of six common probiotics to BPA was first explored in this paper. The result showed that the degradation rate of BPA by Lactobacillus reuteri was the highest among the six common probiotics, which was 69.83%. In addition, no toxic substances were found in the degradation products of Lactobacillus reuteri by GC-MS analysis. Based on this, the enzyme microsphere sustain-released preparation (EMSP) of Lactobacillus reuteri was prepared and characterized. Then the effects of different treatment conditions on the degradation rate of BPA were investigated. Finally, it was applied to orange juice, black tea and mung bean cold tea. The contents of BPA in canned beverage (black tea beverage, orange juice beverage and mung bean cold tea) added with EMSP decreased by 92.74%, 92.33% and 92.33%, respectively, after storage of 1 d. After 27 d, the contents of BPA in these three kinds of canned beverages reached 0. It can be seen that Lactobacillus reuteri has a significant degradation effect on BPA and has great potential and commercial value. Highlights • Lactobacillus reuteri has a significant effect on the degradation of bisphenol A. • No toxic or harmful substances were found in the degradation products of Lactobacillus reuteri. • EMSP has a good slow-release effect and can significantly reduce the content of bisphenol A in canned beverages. [ABSTRACT FROM AUTHOR]

Abstract This study was to develop the quorum sensing (QS) inhibitors from Traditional Chinese Medicinal Plants (TCMs). The water extracts of twenty-nine plants were screened for quorum sensing inhibitory (QSI) activity using two biomonitor strains, Chromobacterium violaceum CV026 (CV026), Agrobacterium tumefaciens A136 (A136). Two of the plants, Galla chinensis and Coptis chinensis , showed a good QS inhibition capacity far below their MIC values, and no effect on their growths. The inhibition zones were 5.16 mm and 12.50 mm for CV026 respectively, and the production of violacein were decreased by 34.5% and 50.44% at 100 μg/mL respectively. QS-mediated β-galactosidase activity in A136 was inhibited strongly of 33.20% at 100 μg/mL by Galla chinensis while Coptis chinensis showed no inhibition. The QS-regulated virulence factors, including swarming motility and biofilm on Pseudomonas aeruginosa PAO1 were inhibited significantly at 10, 50 and 100 μg/mL respectively (P < 0.05). The higher the sub-MIC concentration, the greater the inhibitory effect on the production of violacein, β-galactosidase activity, swarming motility or biofilm formation, showing a good dose-dependent manner (r = 0.9286–0.9999). These findings may be helpful to provide a new aspect regarding the treatment of bacterial infections under a lower concentration of the TCMs. Highlights • Two Traditional Chinese Medicinal Plants showed QSI activities under MIC. • They inhibited violacein production of CV026, motility and biofilm of PAO1. • Galla chinensis inhibited β-galactosidase activity of A136, Coptis chinensis not. • Their QSI activities showed dose-dependent manner under MIC. [ABSTRACT FROM AUTHOR]

The effect of 10 essential oil (EO) components on biofilm formation for vegetable spoilage Erwinia carotovora and Pseudomonas fluorescens at sub-MICs were investigated. Chromobacterium violaceum CV026 (CV026) was selected as quorum sensing (QS) biosensor bacterium. The swimming, swarming, twitching motility, exopolysaccharide (EPS) production and biofilm formation were determined. All tested EO components showed QS inhibition of CV026, E. carotovora and P. fluorescens . Biofilms were inhibited by all EO components by inhibiting their motilities and EPS production. Salicylic acid and thymol showed the best inhibitory effect on biofilm formation of P. fluorescens (37.61%) and E. carotovora (47.24%) respectively. Hexanal as QS inhibitor for biofilm formation was first reported, with inhibition ratio of 25.86% and 20.18%, which was confirmed by scanning electron and fluorescence microscopy. Inhibition of biofilm formation by anti-QS EO components could be novel intervention strategy to enhance safety and quality of vegetables in the food industry. [ABSTRACT FROM AUTHOR]

Automatic image annotation is one of the most important challenges in computer vision, which is critical to many real-world researches and applications. In this paper, we focus on the issue of large scale image annotation with deep learning. Firstly, considering the existing image data, especially the network images, most of the labels of themselves are inaccurate or imprecise. We propose a Multitask Voting (MV) method, which can improve the accuracy of original annotation to a certain extent, thereby enhancing the training effect of the model. Secondly, the MV method can also achieve the adaptive label, whereas most existing methods pre-specify the number of tags to be selected. Additionally, based on convolutional neural network, a large scale image annotation model MVAIACNN is constructed. Finally, we evaluate the performance with experiments on the MIRFlickr25K and NUS-WIDE datasets, and compare with other methods, demonstrating the effectiveness of the MVAIACNN. [ABSTRACT FROM AUTHOR]

Ultrasonic treatment is widely used for surface cleaning of vegetables in the processing of agricultural products. In the present study, the molecular and proteomic response of Pseudomonas fluorescens biofilm cultured on lettuce was investigated after ultrasound treatment at different intensity levels. The results show that the biofilm was efficiently removed after ultrasound treatment with intensity higher than 21.06 W/cm2. However, at an intensity of less than 18.42 W/cm2, P. fluorescens was stimulated by ultrasound leading to promoted bacterial growth, extracellular protease activity, extracellular polysaccharide secretion (EPS), and synthesis of acyl-homoserine lactones (AHLs) as quorum-sensing signaling molecules. The expression of biofilm-related genes, stress response, and dual quorum sensing system was upregulated during post-treatment ultrasound. Proteomic analysis showed that ultrasound activated proteins in the flagellar system, which led to changes in bacterial tendency; meanwhile, a large number of proteins in the dual-component system began to be regulated. ABC transporters accelerated the membrane transport of substances inside and outside the cell membrane and equalized the permeability conditions of the cell membrane. In addition, the expression of proteins related to DNA repair was upregulated, suggesting that bacteria repair damaged DNA after ultrasound exposure. • Pseudomonas fluorescens biofilm was treated by ultrasound at different intensity levels. • Molecular and proteomic response of P. fluorescens biofilm was revealed. • Intensity >21.06 W/cm2 efficiently removed biofilm and suppressed bacterial growth. • P. fluorescens biofilm was stimulated by ultrasound at intensity <18.42 W/cm2. • P. fluorescens initiate stress response and damage repair after ultrasound stimulation. [ABSTRACT FROM AUTHOR]

Abstract: Using an electroless replacement deposition method, large-area superhydrophobic metal substrate could be obtained. The superhydrophobic surfaces were prepared via a replacement reaction between copper substrate and HAuCl4 solution. The roughness of the copper substrate increased much after the replacement reaction. X-ray powder diffraction (XRD) pattern and energy dispersive X-ray (EDX) spectroscopy have proved that gold, CuCl and Cu2O formed on the surface of copper substrate after the replacement reaction. The surface showed remarkable superhydrophobic properties with a contact angle higher than 150 degrees without any modification with a self-assembled monolayer (SAM) of long chain thiol or perfluoro molecules. [Copyright &y& Elsevier]

In industry, Polygalacturonase (PG) is typically used for enzymatic hydrolysis of fruit juice to increase the yield. In the present study, it was found that two pesticides, namely trichlorfon and carbosulfan, which are frequently applied to fruit trees, inhibited the activity of PG and reduced the yield of apple juice. The presence of trichlorfon and carbosulfan reduced the yield by 3.58% and 4.12% during enzymatic hydrolysis of apple juice, respectively. Undoubtedly, this might lead to enormous losses in the juice industry. Analysis of the catalytic mechanism of PG on pectin revealed that the N-acetyl-D-(+)-glucosamine (NAG-404) and tyrosine (TYR-197) residues in the active site played key roles in the process. Nonetheless, it was also determined that various moieties in the pesticides interacted with these amino acids, which led to a decrease in the catalytic activity of the enzyme. Evaluation of the flavor components in enzymatically hydrolyzed apple juice demonstrated that the two pesticide residues could reduce the content of esters, alcohols, and acids by 6.75%, 4.64%, and 3.20%, respectively. Thus, pesticide residues would not only lead to a decrease in the juice yield and change in flavor but would also exhibit potential inhibitory effects on fruit ripening. • The effect of pesticides on apple juice yield was analyzed. • The effect of pesticides on PG activity was evaluated. • The interaction between PG and pesticides was studied. • The effect of pesticides on flavor in apple juice was analyzed. [ABSTRACT FROM AUTHOR]

We prepared double layer membranes containing eugenol (0.2, 0.3, and 0.4 g/100 g) using electrospinning technology and investigated their effects on the postharvest quality of cucumbers. The poly (lactic acid) (PLA) membrane was attached to the collector, and the nanofibers were prepared using an electrospinning device and deposited on the surface of the PLA membrane to form double layer membrane. The results informed that the shelf life of cucumbers packaged with double layer membranes increased from 15 days to 21 days at 4 °C. The double layer membrane containing 0.3 g/100 g eugenol had greater effects on delaying the spoilage process and prolonging the shelf life of cucumber fruits than other membrane. Compared with unpackaged samples, packaged samples had higher hardness values, Peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) enzyme activities, and protein and proline content; and they had lower weight loss, skin color differences values, stickiness values, microbial growth, and malondialdehyde (MDA) and total soluble sugar content. Our results suggest that double layer membranes may be used to extend the shelf life of cucumbers at 4 °C. [Display omitted] • Electrospinning was used to develop active packaging to prolong the shelf-life of cucumbers. • Nanocomposite films have beneficial effects on the postharvest storage of cucumbers. • The shelf-life of cucumbers packaged with nanocomposite films has been extended by 6 days. [ABSTRACT FROM AUTHOR]

The aim of this work was to develop a novel degradable bioactive film with poly (lactic acid), gelatin and eugenol, and electrospinning technology was used to develop an active internal layer for the active films to encapsulate eugenol. An annealing treatment was used to improve the adhesion of the active layer onto the poly (lactic acid) film. The results showed that eugenol could be efficiently encapsulated in nanofibers (92.72 g/100 g). The internal active layer containing it showed a uniform fiber morphology observed by scanning electron microscope. The diameter of nanofibers was enlarged and the hydrophobicity was enhanced, the antioxidant activity and antibacterial activity were improved as the addition of eugenol compared with pure gelatin nanofibers. In particular, nanofibers containing 4 μL/mL eugenol (G3) showed the highest antioxidant activity (32.99 mg DPPH/g dry weight), radical scavenging activity (43.80%), and significant microbial growth inhibition with CFU of about 3 log units (E. coli) and 2.5 log units (S. aureus) lower than the control. In conclusion, our results suggested that active layer could be an effective method to encapsulate eugenol, and the poly (lactic acid)/gelatin nanofibers bilayer film was a novel biodegradable packaging material with excellent antioxidant activity and antibacterial activity. • Electrospinning was used to develop active internal layer for composite film. • Eugenol was encapsulated in nanofibers and enhanced its hydrophobicity. • The composite film is a novel biodegradable material for active packaging. [ABSTRACT FROM AUTHOR]

DNA-templated silver nanoclusters (DNA-AgNCs) is a kind of fluorescent nanoclusters in-situ synthesized on DNA, thereby giving the DNA probe an inherent function of label-free signal output. Herein, the DNA-AgNCs with a GCC-loop-structure which has a quantum field of 51.6% was firstly proposed. It was proved that the addition of the double-stranded structure on the GCC-loop drastically enhanced the fluorescence intensity of the AgNCs. Through the further studies of the relationship between DNA secondary structure and AgNCs, a kind of DNA-AgNCs-probe was designed based on the change of the secondary structure which was induced by the target strand. By this, the fluorescence signal of probe was in "turn on" mode. The probe system could be directly used for the detection of Norovirus RNA, which had a linearity of 20 nM to 1.8 μM with a detection limit of 18 nM. Moreover, this detection platform was also selective to differentiate mismatched RNA. It was expected to be a universal method for different RNA detection by changing the recognition sequence of the probe. • The biosensor succeeds in realizing the quantitative detection of the target RNA. • DNA-templated silver nanoclusters with a quantum yield of 51.60% was found. • It was found that DNA with stable secondary structure facilitates the formation of fluorescent silver nanoclusters. • The constructed probe has great potential in label-free detection of the nucleic acids. [ABSTRACT FROM AUTHOR]

Abstract Melamine is commonly used to manufacture the coating of three-piece tin cans. It may migrate into food in the course of storage, threatening the health of consumers. This work aimed to trace the migration of melamine into food simulants (acetic acid, 3% v/v; ethanol, 10% v/v) during coating of three-piece tin cans in order to propose the critical points for food contamination. High-performance liquid chromatography–tandem mass spectrometry was used to detect melamine in samples. The results indicated that the amount of melamine migrating in the overlay–spray process (step 8) is the largest, significantly higher than that of the other processes (P ≤ 0.05). It was also found that the main source of melamine in the packaging of metal containers is the coating. Therefore, the selection of coatings and the optimization of the process can reduce the migration of melamine. Highlights • Instead of using the soak method, a one-sided migration cell that matches the test method was designed. • An intermediate product of processing was the sample, not a complete packaging material. • Overlay-spray process was identified as the largest melamine migration process. [ABSTRACT FROM AUTHOR]

Schematic diagram of the mechanisms involved in PGE 2 - and VEGF-mediated crosstalk between ECs and BMSCs under hypoxia. (1) Hypoxia promoted cell proliferation, ALP activity, osteogenic differentiation, and ERK phosphorylation in BMSCs, while PD98059 blocked the hypoxia-induced osteogenic differentiation. (2) RAOECs COX-2, VEGF and PGE 2 secretion and migration were augmented under hypoxia, while NS398 prominently impaired ECs response to hypoxia, and exogenous PGE 2 partially reversed the effect of NS398. (3) ECs synthesis and release the COX-2-dependent PGE 2 and VEGF, which signal in a paracrine manner to BMSCs via EP1/2 and VEGFR, triggering phosphorylation of ERK signaling and osteogenic differentiation. ECs migration and PGE 2 , VEGF release were significantly enhanced in ECs: BMSCs group. Moreover, NS398 (pretreated ECs) significantly lessened the PGE 2 , VEGF concentrations in supernatant of the co-culture system. NS398-treated ECs and AH6809/SU5416-treated BMSCs greatly impaired the co-cultured ECs-induced enhancement of BMSCs osteogenic differentiation. [Display omitted] • Hypoxia enhances cell proliferation and ERK-mediated osteogenic differentiation in BMSCs. • Hypoxia augments COX-2-dependent PGE 2 , VEGF release, integrin αvβ3 expression and migration of ECs. • COX-2/PGE 2 /VEGF signaling is involved in intercellular BMSCs: ECs communication under hypoxia. Understanding the crosstalk between endothelial cells (ECs) and bone-marrow mesenchymal stem cells (BMSCs) in response to hypoxic environments and deciphering of the underlying mechanisms are of great relevance for better application of BMSCs in tissue engineering. Here, we demonstrated that hypoxia promoted BMSCs proliferation, colony formation, osteogenic markers expression, mineralization, and extracellular signal-regulated protein kinase (ERK) phosphorylation, and that PD98059 (ERK inhibitor) blocked hypoxia-induced osteogenic differentiation. Hypoxia enhanced ECs migration, cyclooxygenase 2 (COX-2) and integrin α v β 3 expression, and prostaglandin E 2 (PGE 2), vascular endothelial growth factor (VEGF) secretion. NS398 (selective COX-2 inhibitor) and LM609 (integrin α v β 3 specific inhibitor) impaired the ECs response to hypoxia, and exogenous PGE 2 partially reversed the effects of NS398. BMSCs: ECs co-culture under hypoxia upregulated BMSCs osteogenesis and ERK phosphorylation, as well as ECs migration, integrin α v β 3 expression, and PGE 2 and VEGF secretion. NS398 (pretreated ECs) lessened PGE 2 , VEGF concentrations of the co-culture system. NS398-treated ECs and AH6809 (combined EP1/2 antagonist)/L-798106 (selective EP3 antagonist)/L-161982 (selective EP4 antagonist)/SU5416 [VEGF receptor (VEGFR) inhibitor]-treated BMSCs impaired the co-cultured ECs–induced enhancement of BMSCs osteogenic differentiation. In conclusion, hypoxia enhances BMSCs proliferation and ERK-mediated osteogenic differentiation, and augments the COX-2–dependent PGE 2 and VEGF release, integrin α v β 3 expression, and migration of ECs. COX-2/PGE 2 /VEGF signaling is involved in intercellular BMSCs: ECs communication under hypoxia. [ABSTRACT FROM AUTHOR]

Organophosphorus pesticides (OPPs) are a group of common residual pollutants in food that cause serious harm to human health. In the present study, the ability of 10 lactic acid bacteria (LAB) to degrade OPPs (dimethoate, parathion methyl, trichlorfon and chlorpyrifos) was explored for their potential application to degrade OPPs in fermented food. The results showed that some LAB can survive in the presence of OPPs and degrade them significantly in a short time. Among these, Lactiplantibacillus plantarum subsp. plantarum CICC20261 (L. plantarum 20261) showed the highest degradation ability. The degradation behavior of OPPs by L. plantarum 20261 followed pseudo-zero-order kinetic model (k = 1.0939–1.5915). Phosphatase produced by the strain played the key role in the degradation of OPPs because its activity was positively related to the degradation of OPPs (r = 0.975–0.995). Phosphatase could degrade OPPs rapidly in vitro , further confirmed that L. plantarum 20261 degraded rather than adsorped the OPPs. In addition, the excellent antioxidant ability of LAB and the tolerance of simulated gastric and intestinal juices showed their potential protective effects against oxidative damage induced by pesticides in vivo. • Lactic acid bacteria were screened for degrading organophosphorus pesticides (OPPs). • The phosphatase activity was positively related to the degradation rate of OPPs. • The crude phosphatase could rapidly degrade OPPs in vitro. • First study on reducing oxidative stress caused by pesticides by lactic acid bacteria. [ABSTRACT FROM AUTHOR]

During preservation of nuts, nut oils are easily oxidized; hence, peroxide value (PV) is an important evaluation index. In this study, a novel method for the determination of the PV of nuts based on partial-least-square regression (PLSR) and Forest random PLSR (RF-PLSR) model was established. Meanwhile, the Raman spectrum was processed by 24 spectral pretreatment methods to transform the whole Raman band, and the best band was selected by RF method. Among the whole bands, 36 wavenumbers were selected to establish the PLSR model. The R-square of the correction set (R2c) and prediction set (R2p) of the optimal Standard normal variate transformation + first Derivative-PLSR model and RF-PLSR were 0.9552, 0.8672, 0.8048, and 0.7927, while the root-mean-square error of calibration (RMSEC) and prediction (RMSEP) were 0.067, 0.1100, 0.1514, and 0.1547, respectively. These results showed that Raman spectroscopy combined with chemometrics could be used to establish a rapid, nondestructive, and precise method for the determination of oil oxidation index. • Dynamic monitoring of nut oil oxidation was done through Raman technology. • Comparison was done on the stability and precision of different models established by different pretreatments. • PLSR modeling was performed by the Random Forest algorithm to quantify oil peroxide values. [ABSTRACT FROM AUTHOR]