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A ladder-shape melting temperature isothermal amplification (LMTIA) assay was established and used to detect soybean components in edible oils.

This study is to develop a technology for processing red bean (Vigna angularis), and to make red bean becoming a preconditioned grain product for fast cooking. Red bean was subjected to a pre-precondition treatment with high temperature and high pressure. The nutritional composition, color, starch structure and texture of the processed red beans were studied. The treatments led to color change and increased the starch and protein contents of red bean, while the lipid content of the treatment red bean was found to be reduced. The precondition process shortened the cooking time of red beans by 2.6 times, while it still retained the structural integrity of the red beans. A significant change in textural properties (hardness, gumminess and chewiness) after precondition treatment was observed. The result from this study will be the basic supports for further developing the precondition technology of grain products.

A novel method, termed ladder-shape melting temperature isothermal amplification (LMTIA), was developed in this study. As a proof of concept, one pair of primers or two pairs of nested primers and a thermostable DNA polymerase were employed to amplify the internal transcribed spacer of Oryza sativa with the ladder-shape melting temperature curve. Our results demonstrated that the LMTIA assay with nested primers was 50-fold more sensitive than the LAMP assay with the same level of specificity. The LMTIA method has the potential to be used for the prevention and control of emerging epidemics caused by different types of pathogens.

Two new rhamnosides, 18-O-α-l-rhamnopyranosylabietic acid (1) and (E)-3,5-dimethoxystilben-4'-O-α-l-rhamnopyranoside (2), five known glucosides (3-7) along with three others were isolated from Cynanchum atratum roots. The structures of new compounds were elucidated by physical data analyses such as NMR, UV, IR, HR-ESI-MS, as well as acid hydrolysis. All of them were assessed for their antioxidant activities through 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical ion (ABTS•

A new hydrocinnamoyl glucoside, 1-O-(4-hydroxyhydrocinnamoyl)-β-D-glucopyranose (1), together with fifteen known glycosides, including two phenylethanoid glycosides (2–3), two cinnamoyl glycosides (4–5), six phenolic glycosides (6–11), one lignan glycoside (12) and four megastigmane glycosides (13–16) were isolated from a 95% EtOH extract of the Typhonium giganteum rhizomes. The sixteen glycosides were structurally characterized by NMR, HRESIMS, enzymatic hydrolysis and comparison with literature. Upon evaluating inhibitory activities of compounds 1–16 against mushroom tyrosinase at 25 μM, compounds 10 and 11 exhibited obvious inhibitory activities, with %inhibition values of 20.94±0.59%, 23.28±1.09%, respectively, with arbutin used as the positive control (26.21±0.58%).

Here we describe the improvement of pesticide residue extraction from tomatoes by an improved QuEChERS method. Through Plackett–Burman design, 4 significant variables out of 11 potential variables were identified that could influence the relative deviation of measurements. The 11 variables were: amount of sample, C18, Na2SO4, NaCl, MgSO4, NaAc, GCB (graphitized carbon black), and PSA (primary–secondary amine); ACN volume; percentage of FA (formic acid); and centrifugation time. The amounts of GCB, Na2SO4, PSA and sample were significant variables, which were further optimized using a Box–Behnken design to predict the optimum extraction conditions. The method presented recoveries between 72.5 and 119.7%, with relative standard deviations ranging from 1.17 to 14.62% for all real samples spiked with pesticides at three different fortification levels. Overall, methods met the requirements of national standard for pesticide residue analysis. The results indicate that the improved QuEChERS method is suitable for the routine monitoring of 20 pesticides which often are detected in tomato samples.

Angelica dahurica is an important medicinal plant, which has been widely used in medicines and skin-whitening products. In the investigation of phytochemicals present in A. dahurica roots, three unusual furanocoumarin rhamnosides, angelicosides I–III (1–3), one undescribed furanocoumarin glucoside, angelicoside IV (4), together with eight known compounds (5–12) were isolated. Their structures were characterized by a combination of UV, IR, NMR, HRESIMS, along with acid hydrolysis and enzymatic hydrolysis. All the isolated compounds were tested for their mushroom tyrosinase inhibitory activities, and compounds 1, 2, and 11 showed moderate activities.

One novel monoterpene rhamnoside (1) and 7 known monoterpenes (2-8) were isolated from the ethanol extract of Cynanchum atratum for the first time. Their structures were identified by comprehensive spectroscopic data analysis such as nuclear magnetic resonance, high-resolution electrospray ionization mass spectra, optical rotatory dispersion, and acid hydrolysis. In the subsequent antioxidant assay, compound 8 exhibited obvious 2,2-diphenyl-2-picrylhydrazyl hydrate radical scavenging activity.

Twelve cinnamoyl glucoside derivatives were prepared by glycosylation of glucosyl trichloroacetimidate and cinnamic acid derivatives, followed by dechloroacetylation with a pyridine/H2O mixture. Their structures were characterized by 1H and 13C NMR, as well as mass analysis. All the products were tested for their antiproliferation activities against murine melanoma B16-F10 cell line. Compounds 4e-4j were able to inhibit the proliferation of murine melanoma B16-F10 cell line with IC50 values of 17.38 ± 0.07, 9.87 ± 0.09, 9.69 ± 0.12, 29.42 ± 0.04, 32.95 ± 0.08, 25.68 ± 0.09 μM, respectively.

A novel method termed isothermal amplification of nucleic acids with ladder-shape melting curve (LMCP) was developed in the study. In this method, one pair of primers or two pairs of nested primers and a thermostable DNA polymerase (large fragment) were employed to amplify the internal transcribed spacer (ITS) of Oryza sativa with ladder-shape melting curve. Our results demonstrated that the LMCP assay with nested primers was 50-fold more sensitive and one-hour faster than the LAMP assay with the same level of specificity. The LMCP method has the potential to be used for the prevention and control of the emerging epidemics.

Two undescribed phenylethanoid glycosides, Ginkgoside C (1) and D (2), together with ten known glycosides (3−12) were isolated from Ginkgo biloba leaves. Their structures were characterized by physical data analyses such as NMR, HRESIMS, as well as chemical hydrolysis. All compounds were tested for their tyrosinase inhibitory activities. At a concentration of 25 μM, compounds 2, 4, 5, 6, and 11 showed obvious mushroom tyrosinase inhibition activities, with %inhibition values of 19.12 ± 2.59%, 25.79 ± 1.83%, 16.07 ± 1.07%, 24.46 ± 1.10%, 18.64 ± 3.62%, respectively, with kojic acid used as the positive control (27.50 ± 2.72%).

Cathodic electrodeposition of PbSe is carried out in aqueous alkaline selenosulfate (SeSO32−) bath of lead complex ions at various conditions of electrolysis. Micro- and nanocrystalline PbSe thin films were grown onto glassy carbon (GC) substrates by potentiostatic and cyclic voltammetric (CV) methods respectively. Structure and surface morphology of thin films were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). X-ray diffraction indicates that the PbSe films have cubic structure without any impurities. The SEM micrograph showed the films cover GC substrate completely and consisted of irregular shaped grains.

Dietary fiber is a carbohydrate-based polymer with significant health benefit, soybean residues are generally discarded in food industries during the production of soybean milk and tofu. In this study, ultrasound-assisted alkali extraction technology was employed to extract insoluble dietary fiber from soybean residues. And the physicochemical properties of insoluble dietary fibers were also studied. The optimal conditions for insoluble dietary fibers were determined to be solid to liquid ratio of 1:50, alkali concentration of 0.05 mol/L, ultrasound power of 450 W, reaction time of 10 min and reaction temperature of 30 °C. The yield of insoluble dietary fiber was 744.3 ± 13.2 mg/g raw soybean residues using the combination of ultrasound and alkali. In addition, the insoluble dietary fibers had higher water retention capacity, swelling capacity than those of untreated soybean residues, while the oil retention capacity of insoluble dietary fibers was lower than that of untreated soybean residues.

Feruloylated monoacyl- and diacyl-glycerols (FMAGs and FDAGs) are lipophilic antioxidants and potential UV absorbers. FMAGs and FDAGs were synthesized by a novel chemoenzymatic method: firstly, ferulic acid was esterified with glycerol to synthesize glyceryl ferulate, using p-toluenesulfonic acid as chemical catalyst in 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF(4)); secondly, glyceryl ferulate was esterified with oleic acid to synthesize FMAGs and FDAGs, using Novozym 435 as biocatalyst in 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim]PF(6)). The conversion of ferulic acid and yield of glyceryl ferulate in the first reaction were both 98%. The yields of FMAGs and FDAGs in the second reaction reached 34 +/- 2% and 66 +/- 3%, respectively.

Water chestnut is one of the most popular vegetables in Asian countries that grows in shallow water. Eighteen water chestnut samples were collected from Lake Tai and six samples were bought at markets in Wuxi, China, in October 2007. Extraction solution of water chestnut was cleaned up with a solid phase extraction column and immunoaffinity chromatography cartridges, then the microcystin (MC) level was detected by indirect competitive enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-mass spectrometry (LC-MS). The results of ELISA showed that there were six samples collected from Lake Tai which contained MCs; the highest level of total MCs was 7.02 ng/g. The results of LC-MS confirmed that MC-LR and MC-RR were present in five samples. The highest level of MC-LR was 1.02 ng/g and that of MC-RR was 4.44 ng/g. Heavy cyanobacterial blooms had occurred, and MCs were detected in water at the points in Lake Tai where MCs occurred in water chestnuts collected in 2007. MCs were not detected in the six samples bought at Wuxi markets. The results suggest that MCs can accumulate in water chestnuts, which is a potential hazard for human health.

Microcystin-LR (MC-LR) is a heptapeptide hepatotoxin produced by cyanobacteria. Immunoaffinity chromatography (IAC) column was prepared with CNBr-activated Sepharose 4B and monoclonal antibody of MC-LR. Water sample was cleaned up by IAC column and the content of MC-LR in water was determined by liquid chromatography-mass spectrometry (LC-MS). The results suggested that the IAC column exhibited highly selective specificity for MC-LR and selective removed interference from complex water sample. Water sample was concentrated for 2,000-fold through once purification. Cyanobacterial blooms had broken out in 2007 in Lake Tai, the third largest freshwater lake in China. Water samples from two parts of Lake Tai had been analyzed. The highest concentration of MC-LR in water from Lake Tai was 0.522 microg/L.

Poly(lactic acid) (PLA) fibers of submicron sizes encapsulating allyl isothiocyanate (AITC) (PfA) were made and electrospun onto the surfaces of PLA films. SEM examination confirmed the fusion of the two phases to form a bilayered fiber-grafted film after the film underwent air blowing and water washing to remove the nongrafted fibers. The fiber-grafted PLA films (PfA-g-film) retain the mechanical properties of PLA. The release of AITC from the fibers was temperature dependent. At temperatures lower than 4°C, the incorporated AITC remained within the fibers without losing activity; at room temperature, AITC released in a sustained manner over weeks. The release of AITC was also dependent on its initial concentration in the PLA electrospinning solution; samples with more AITC incorporated showed a higher release rate. PfA-g-films significantly inhibited the growth of Listeria innocua and Escherichia coli k12 when tested on package foods. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42475.

An ionic liquid (IL) system for the enzymatic epoxidation of soybean oil was studied. The effects of active oxygen carriers (different fatty acids) and ILs ([Bmim]PF6 and [Bmim]BF4) on the enzymatic epoxidation were investigated. Response surface methodology (RSM) was used to study and optimize the effects of variables (reaction time, reaction temperature, molar ratio of H2O2/C=C-bonds, and molar ratio of fatty acid/C=C-bonds) on the epoxy oxygen group content (EOC) of epoxidized soybean oil (ESO). Results showed that the enzymatic epoxidation of soybean oil can be enhanced using tetradecanoic acid (C13H27COOH) as active oxygen carrier and [Bmim]PF6 as reaction medium. The optimum EOC of ESO was 5.9 ± 0.3% under the following conditions: reaction temperature 46°C, reaction time 11 h, enzyme load 3% (w/w, relative to the weight of soybean oil), molar ratio of H2O2/C=C-bonds 1.8:1, and molar ratio of C13H27COOH/C=C-bonds 0.5:1.