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A magnetic beads (MBs)–assisted fluorescence aptasensing approach based on dual DNA tweezers and magnetic separation was established for the detection of ochratoxin A (OTA) and fumonisin B1 (FB1). A dual DNA tweezers structure with four ends linked with fluorophores (FAM, ROX) and quenchers (BHQ1, BHQ2) was designed, and produced the high initial fluorescence signals because of the long spatial distance between FAM and BHQ1, ROX, and BHQ2. Bio-aptamer/anti-aptamer of OTA and bio-aptamer/anti-aptamer of FB1 were respectively annealed to form dsDNA, and immobilized to MBs coated with streptavidin (SA). With the existence of OTA and FB1, OTA and FB1 preferentially bound with their respective bio-aptamers, which made anti-aptamers dissociate from dsDNA coupled on MBs. After magnetic separation, the dissociated anti-aptamers reacted with dual DNA tweezers, respectively, which made DNA tweezers close and the fluorescence was quenched. The linear ranges of approach for OTA and FB1 detection were 0.05–20 ng/mL and 0.1–40 ng/mL, respectively. The limit of detection for OTA and FB1 was 0.029 ng/mL and 0.061 ng/mL. The prepared MBs-assisted fluorescence aptasensing approach was applied to detect OTA and FB1 in spiked red wine and corn samples, which showed good recoveries between 92 and 106%. [ABSTRACT FROM AUTHOR]

In order to stabilize the whole wheat flour and extend its shelf life, microwave was employed to heat the wheat bran to inactivate the lipase in this paper. The effects of microwave heating of wheat bran on the lipase activities, gluten properties, dough properties and storage stability of the stabilized whole wheat flour, and the quality of steamed bread made of stabilized whole wheat flour were investigated. Furthermore, molecular docking was applied to interpret the mechanism. The results showed that microwave can reduce lipase activity, maintain the quality of whole wheat flour dough and steamed bread, and retard rancidity. The molecular docking results displayed that the conformation of the amino acids chains near the lipase catalytic center changed, which made the substrate difficult to enter the catalytic center and prevented the hydrolysis of the fat substrate. [ABSTRACT FROM AUTHOR]

Objectives: Vitamin D deficiency was associated with obesity. However, the causal relationship remains controversial. We hypothesized that there would be family-based associations in both vitamin D deficient families and obese families for the SNPs associated with vitamin D deficiency, if vitamin D deficiency was a causal factor of obesity. We aimed to investigate the family-based association of SNPs in CYP27B1 with both vitamin D deficiency and obesity.Methods: Four hundred and nineteen pedigrees containing 1505 rural individuals aged from 18 to 79 years in Henan Province of China were included in this study. Family-based associations of rs10877012 and rs4646536 in CYP27B1 with vitamin D deficiency and obesity were investigated. Serum 25(OH)D3 concentration <20 μg/L was defined as vitamin D deficiency. BMI ≥ 28 kg/m2 was applied for obesity definition. Taqman assays were applied for SNP genotyping. Family-based associations were investigated with FBAT software.Results: It was shown that vitamin D deficiency was a risk factor of obesity (adjusted OR: 1.332, 95% CI: 1.042-1.703, P = 0.022). Furthermore, there were family-based associations for allele T of rs10877012 and allele T of rs4646536 in both vitamin D deficient families and obese families (P < 0.05). Both rs10877012 and rs4646536 were associated with serum 25(OH)D3 levels between siblings (P < 0.05), but not BMI (P > 0.05). In addition, there is linkage disequilibrium between rs10877012 and rs4646536 (D' = 1.0, r2 = 0.992).Conclusion: Vitamin D deficiency may be a causal factor of obesity. Maintaining sufficient vitamin D is beneficial to obesity prevention. [ABSTRACT FROM AUTHOR]

The effect of microwave heating wheat grains (700 W for 0-60 s) on gluten, farinograph, pasting properties and baking (steamed bread and biscuit) of flour was studied. The lipase (LA) and lipoxygenase (LOX) activities of the microwave-treated wheat were monitored, and the accelerated storage at 35 °C of whole wheat flour was also investigated. The results showed that the gluten, farinograph properties and viscosity were influenced to a small extent when microwave treatment time was less than or equal to 20 s and the temperature of the grains was less than or equal to 56 °C. Texture profile analysis indicated that steamed bread made from wheat treated by microwave for 20 s was softer and of better quality. Microwave treatment for longer periods (≥30 s) increased the temperature ≥68 °C, that damaged the gluten and made wheat unsuitable for making steamed bread; however, suitable for making food with lower gluten requirements, such as biscuits. The results obtained from enzyme activity and accelerated storage experiments demonstrated that microwave treatment could inactivate LA and LOX and extend the shelf-life. [ABSTRACT FROM AUTHOR]

Capillary electrophoresis using 1-butyl-3-methylimidazolium tetrafluoroborate as background electrolyte for the separation and determination of 11 amino acids was studied. Several parameters, such as ionic liquid concentration, pH of background electrolyte and applied voltage, were optimized. Amino acids were derived with Sanger’s reagent (2,4-dinitrofluorobenzene) and the detection was performed by an ultraviolet absorption detector at 360 nm. Under selected conditions, 11 amino acids were completely separated within 16 min. The RSD values of integrated areas and migration times are <3.03 and <1.64%, respectively. The electroosmotic flow can be influenced by imidazolium cation, and the association between the imidazolium cation and the derived amino acids plays an important role in the separation mechanism. This method not only provides an approach for the separation and determination of amino acids, but is also an extension of the ionic liquid application to capillary electrophoresis. [ABSTRACT FROM AUTHOR]

Threat-based awe such as those elicited by natural disasters could also elicit a sense of a small self as positive awe did, further promoting prosociality. Inspired by this finding and research on sense of global community, we intended to examine the potential mediating roles of sense of a small self and sense of global community in the relation between natural disaster-elicited awe and willingness to help people in afflicted areas. Six hundred and eighty undergraduate students in their first year (Mage = 18.52) were conveniently chosen as participants. After viewing a 4-min video successively displaying four types of natural disasters (i.e., earthquakes, volcanoes, tsunami, typhoon) with their massive destruction, participants reported on items regarding their feelings of awe over the disasters, sense of a small self, sense of global community, and their willingness to help people in the disaster-stricken areas. Results indicated that all the direct paths and indirect paths in the hypothesized meditational model were significant, suggesting that temporary disaster-induced awe might produce a self-diminishing effect and enhance people's sense of global community, which finally enhance their willingness to help people in the disaster-stricken areas. [ABSTRACT FROM AUTHOR]