Dalebutler8134

Propamocarb is a carbamate fungicide used to control Phytophthora disease. Frequent and large-scale use of propamocarb means that it poses a potential threat to the health of consumers. Monoclonal antibodies against propamocarb were prepared using a hapten of propamocarb that was generated by introducing a benzene ring and a carboxyl group into the structure of propamocarb. A lateral flow immunoassay strip was developed for the detection of propamocarb in tomato and cucumber samples using the gold nanoparticle-labeled antibody. The immunoassay strip was found to provide a visible limit of detection was 5 ng/g and the cut-off value was 250 ng/g for propamocarb in food samples. For quantitative analysis, the calculated limits of detection (LODs) of the immunoassay strip were 1.43 ng/g and 0.44 ng/g in cucumber and tomato, respectively. Using the immunoassay strip, the average recoveries ranged from 95.5 ± 5.4% to 108.8 ± 6.8%, with CVs of 3.1-6.2% for the cucumber, and the average recoveries were 95.1 ± 6.5%-111.9 ± 4.2%, with CVs ranging from 3.7% to 6.8% for tomato samples. All the results demonstrated that the immunoassay strip was suitable for the detection of propamocarb in fruits and vegetables.5-Hydroxymethylfurfural (HMF) and acrylamide (AA) are neoformed food contaminants. In this study, the simultaneous inhibition of HMF and AA by histidine (His) were investigated. In the asparagine (Asn)/glucose (Glc) model system, the inhibition ratios of HMF and AA were in the range of 28-58% and 0-71% when 20 mmol/L His was added. In cookies, His also exhibited excellent inhibition effects on both HMF and AA. At the His concentration of 2% (w/w), the inhibition ratios of HMF and AA reached 90% and 65%. Additionally, the sensory quality of cookies was not affected significantly. Qualitative results suggested that His inhibited the formation of AA by the competitive reaction between His and Asn for Glc, as well as directly eliminated the formed HMF and AA via the carbonyl-amine reaction and the Michael addition, respectively. This study revealed that His could be applied for the inhibition of HMF and AA in heated food.In this study, combining metabolome and transcriptome, color related attributes and phenolic compositions of Tunisian pomegranate arils from 7 Chinese regions at same developing stage were studied. The total anthocyanin (TAC), flavonoids, and percent polymeric color (PPC) were ranged at 8.93-28.41 mg/100 g arils, 37.55-69.72 mg/100 g arils, and 3.38-21.96%, respectively. In total, 51 phenolic compounds were characterized, most of which were markedly higher in reddish-purple pomegranate arils than those levels in reddish pomegranate arils. In contrast, the accumulation of tannins was significantly higher in reddish pomegranate arils. Among the 49 differentially expressed genes, 8 and 5 genes were matched to β-glucosidase and peroxidase, respectively. Correlation analysis showed that PPC was negatively correlated with 10 phenolic metabolites and TAC, positively correlated with L*, polymeric color, and 1 gene (|r| > 0.7, p less then 0.01). Our results provide new insights for understanding the difference in coloration of pomegranate arils.Yellowing is a critical issue that reduces quality and commodity value of rice. This article presents an overview on rice yellowing and the mechanism of rice yellowing was addressed as the emphasis. Doxorubicin ic50 The change of physicochemical and nutritive properties in yellowed rice depends on the exposure temperature and time, as well as rice cultivar. The temperature and moisture on rice yellowing were dominant. There is no consensus on the relationship between microorganisms and rice yellowing. The occurrence of yellowing is mainly associated with heat stress induced by heaping heat or respiration of grain, and the yellowing is the collective result of primary and secondary metabolism. The upregulation of flavonoids is the direct cause of rice yellowing, which can be used as metabolic markers of rice yellowing. The Maillard reaction also contributes to yellowing during storage. Aeration and cooling are recommended to lessen the occurring of rice yellowing during commercial storage.Supercooling can preserve beef without freezing damage, whereas maintaining the supercooled state is difficult. An innovative method of static magnetic field extended supercooling (SM-ES) was proposed to maintain the non-frozen state of beef. Effect of SM-ES (-4 °C + SMF) compared with refrigerated (4 °C), slow-frozen (-4 °C) and frozen (-18 °C) treatment on beef quality was investigated. Results demonstrated that SM-ES successfully preserved beef at -4 °C without ice nucleation for 14 days. The SEM images revealed that the microstructure of slow-frozen/frozen samples was damaged due to crystallizing, while the ice nucleation was not observed in SM-ES treated beef. Compared with refrigerated, slow-frozen and frozen treatment, the drip loss of SM-ES decreased by 21.9%, 47.8% and 30.9%, respectively. The lipid oxidation degree of beef decreased following SM-ES treatment. SM-ES treatment extended the shelf-life of beef for more than 6 days compared with refrigeration while prevented its crystallizing.Clenbuterol is present in animal tissues and organs and, therefore, potentially present in gelatin derived from animal sources. The objective of this study was to develop a method for identify an quantify traces of clenbuterol in gelatin and jellies. The clenbuterol calibration curve showed linearity in the range of 20-1000 pg mL-1. The detection and quantification limits were 5 pg g-1 and 10 pg g-1, respectively. The recovery of the analyte ranged from 93.4 to 98.7% with an intra-day RSD% (n = 4) of 1.25%-3.25%, and an inter-day RSD% (n = 12) of 0.5%-2.25%, with good linearity (R2 = 0.99). The method developed and validated was successfully applied in 54 gelatin samples, 57.4% of which showed clenbuterol. This UHPLC-MS/MS method combines high sensitivity with good selectivity and short chromatographic run time.Conventional and innovative (microwave-assisted and subcritical water extraction) techniques were applied to investigate the bioactive content of traditional plant - Teucrium montanum. Verbascoside and echinacoside, identified and quantified using LC-MS/MS and HPLC-PAD, were found to be the predominant phenolics in all extracts. Infusion (30 °C, 30 min) was characterized with the highest total phenolic content and antioxidant capacity and was further used for encapsulation into liposomes. Formulation of liposomes with a high encapsulation efficiency of echinacoside (68.27%) and verbascoside (80.60%), satisfactory physical properties, including size (326.2 nm) and polydispersity index (0.34), was achieved, although determined zeta potential (-23.03 mV) indicated their instability. Formulated liposomes were successfully coated with pectin and alginate that was also proved by FTIR analysis. Liposomes coated with pectin showed the most desirable in vitro digestion release of verbascoside and echinacoside, while alginate as liposome surface layer proved to be more appropriate for their retention during storage time.This study aimed to investigate the effect of myofiber changes and protein oxidation on water holding capacity (WHC) of bighead carp fillets stored at -20 °C. WHC, microstructure, protein oxidation parameters, and specific modifications of oxidized amino acids were analyzed during 9 months of frozen storage. Results indicated that WHC decreased accompanied by myofibers' structural changes (including the formation of cavities among myofibers, breakage of myofibrils and myofibers, and shortening of sarcomeres) and protein oxidation. SDS-PAGE and carbonyl and sulfhydryl content determination of myofibrillar proteins and exudates gave a detailed description of the protein oxidation. LC-MS/MS analysis demonstrated that oxidation, di-oxidation, and 4-hydroxy-2-nonenal (HNE) and malondialdehyde (MDA) adduction were the top four oxidative modifications of proteins. Oxidative modifications impaired configuration and polarity of proteins, which may further affect WHC. This study provides plausible explanations to support the role of protein oxidation in the decrease of WHC in frozen fillets.To use hydrocolloids for improving the breadmaking performance of whole wheat flour dough, relationships between hydrocolloid addition and dough thermomechanical, viscoelastic and microstructural properties were investigated. The responses of dough thermomechanical and viscoelastic properties to hydrocolloid addition depended on the hydrocolloid type. A power-law gel model fitted well to the linear and non-linear viscoelastic parameters, i.e., G'(ω), G(ω) and J(t), of doughs. The model parameters gel strength (S) and exponent (n) were well indicative of hydrocolloid-induced changes in dough strength and relaxation behavior. The torque-scale mixolab parameters C2, C3 and C5, showed a good linear relationship with hydrocolloid addition. These parameters were also well correlated with S and n. Hydrocolloids played a crucial role in the modification for dough microstructure by forming a more continuous gluten network and better connection between starch granules and protein matrix.This study investigated seven pesticides in vegetables produced in rural South-western Uganda to determine their suitability for human consumption. Pesticide residue concentrations (ppm) were determined using QuEChERS method, LC-MS/MS, GC-MS/MS and UV-Vis. Cypermethrin, dimethoate, metalaxyl, profenofos, malathion, dichlorvos and mancozeb concentrations detected in sprayed samples ranged between 0.00403 and 0.05350, 0.17478-62.60874, 0.12890-3.55681, 0.00107-0.59722, 0.03144-0.63328, 0.00240-0.34102 and 0.00001-0.00244, respectively. The residues exceeded MRLs in sprayed samples (59.52%), unsprayed samples (18%) and market samples (8%). The quality index of the market vegetables was found to be optimal (14.29%), good (75%), adequate (3.57%) and inadequate (14.29%). Pesticide residues may lower food quality and pose risk to human health. Therefore, regulation and monitoring pesticide residues in vegetables produced in south-western Uganda in order to avoid harmful effects on human health would be paramount.Soft rot and Pythium leak are postharvest storage diseases of potato tubers that can cause substantial crop losses in the US. This study focused on detecting volatile organic compounds (VOCs) associated with rot inoculated tubers during storage (up to 21 days) using headspace solid-phase microextraction (SPME) coupled to gas chromatography (GC) with mass spectrometry (MS) and flame ionization detector (FID) analysis. Russet Burbank and Ranger Russet tubers were inoculated with the rot pathogens. Static sampling with 50 min trapping time followed by GC-MS and GC-FID analysis identified 23 and 30 common VOCs from the pathogen inoculated tubers. Overall, n,n-dimethylmethylamine, acetone, 1-undecene, and styrene, occurred frequently and repeatability in inoculated samples based on GC-MS analysis, with the latter two found using GC-FID analysis as well. Identification of such biomarkers can be useful in developing high-throughput VOC sensing systems for early disease detection in potato storage facilities.