Stereoselective Determination of a Novel Chiral Insecticide,Sulfoxaflor, in Brown Rice,Cucumber and Apple by Normal‐Phase High‐Performance Liquid Chromatography

An effective high‐performance liquid chromatography method was developed for the stereoselective determination of a new sulfoximines insecticide, sulfoxaflor, in brown rice, cucumber and apple. Target compounds were extracted with acetonitrile and an aliquot cleaned with Cleanert PestiCarb/PSA (primary and secondary amine) cartridge. Five polysaccharide‐based columns were investigated on the separation of sulfoxaflor stereoisomers and the best was achieved on a ChromegaChiral CCA column with n‐hexane/ethanol/methanol (90:2:8, v/v/v) as mobile phase by UV detection at 220 nm at 20ºC. The resolutions of the four stereoisomers were 1.85, 1.54 and 3.08, and the elution order was identified by optical rotation and stereoisomers ratio. The mean recoveries of sulfoxaflor stereoisomers ranged from 77.1% to 99.3%, with relative standard deviations less than 8.9% at three concentration levels in all matrices. The limits of detection for all stereoisomers varied from 0.05 mg/kg to 0.07 mg/kg, while the limit of quantification did not exceed 0.22 mg/kg. The method was then successfully applied to determine the sulfoxaflor stereoisomers in authentic samples, confirming that it is convenient and reliable for stereoselective determination of sulfoxaflor stereoisomers in food. Chirality 26:114–120, 2014. © 2014 Wiley Periodicals, Inc.     

Convergent evolution of the gut microbiome in marine carnivores

The gut microbiome can help the host adapt to a variety of environments and is affected by many factors. Marine carnivores have unique habitats in extreme environments. The question of whether marine habitats surpass phylogeny to drive the convergent evolution of the gut microbiome in marine carnivores remains unanswered. In the present study, we compared the gut microbiomes of 16 species from different habitats. Principal component analysis (PCA) and principal coordinate analysis (PCoA) separated three groups according to their gut microbiomes: marine carnivores, terrestrial carnivores, and terrestrial herbivores. The alpha diversity and niche breadth of the gut microbiome of marine carnivores were lower than those of the gut microbiome of terrestrial carnivores and terrestrial herbivores. The gut microbiome of marine carnivores harbored many marine microbiotas, including those belonging to the phyla Planctomycetes, Cyanobacteria, and Proteobacteria, and the genus Peptoclostridium. Collectively, these results revealed that marine habitats drive the convergent evolution of the gut microbiome of marine carnivores. This study provides a new perspective on the adaptive evolution of marine carnivores.     

Flower pollination algorithm with runway balance strategy for the aircraft landing scheduling problem

Aircraft landing scheduling is a challenging problem in the field of air traffic, whose objective is to determine the best combination of assigning the sequence and corresponding landing time for a given set of aircraft to a runway, and then minimize the sum of the deviations of the actual and target landing times under the condition of safe landing. In this paper, a flower pollination algorithm embedded with runway balance is proposed to solve it. Context cognitive learning and runway balance strategy are devised here to enhance its searching ability. 36 scheduling instances are selected from OR-Library to validate its performance. The experimental results show that the proposed algorithm can get the optimal solutions for instances up to 100 aircrafts, and is also capable of obtaining better solutions compared with SS, BA and FCFS for instances up to 500 aircrafts in a shorter time.     

Expression of Hsp27 correlated with rat detrusor contraction after acute urinary retention

Heat shock protein 27 (Hsp27) can regulate actin cytoskeleton dynamics and contractile protein activation. This study investigates whether Hsp27 expression is related to bladder contractile dysfunction after acute urinary retention (AUR). Female rats were randomized either to AUR by urethral ligation or to normal control group. Bladder and smooth muscle strip contraction at time points from 0 h to 7 days after AUR were estimated by cystometric and organ bath studies. Hsp27 expression in bladder tissue at each time point was detected with immunofluorescence, Western blots, and real-time PCR. Expression of the three phosphorylated forms of Hsp27 was detected by Western blots. Smooth muscle ultrastructure was observed by transmission electron microscopy. Data suggest that maximum detrusor pressure and both carbachol-induced and spontaneous detrusor strip contraction amplitude decreased gradually for the duration from 0 to 6 h, and then increased gradually to near-normal values at 24 h. Treatment of muscle strips with the p38MAK inhibitor, SB203580, inhibited carbachol-induced contractions. Smooth muscle ultrastructure damage was the highest at 6 h after AUR, and then lessened gradually during next 7 days, and ultrastructure was close to normal. Expressions of Hsp27 mRNA and protein and the proteins of the three phosphorylated forms were higher at 0 h, decreased to lower levels up to 6 h, and then gradually increased. Therefore, we conclude that rat bladder contractile function after AUR worsens during 0–6 h, and then gradually recovers. The findings of the current study suggest that Hsp27 modulates bladder smooth muscle contraction after AUR, and that phosphorylation of Hsp27 may be an important pathway modulating actin cytoskeleton dynamics in bladder smooth muscle contraction and reconstruction after injury.     

The antihypertensive effect of peptides: a novel alternative to drugs?

Many types of bioactive peptides that inhibit angiotensin I, angiotensin I converting enzyme (ACE) and Ang II type 1 receptor (AT1) in the cardiovascular system contribute to the prevention and treatment of hypertension. These inhibitory peptides are derived from many food proteins or artificial synthetic products. Further research examining the bioavailability of ACE inhibitory peptides will lead to the development of more effective ACE inhibitory peptides and foods. Our research also demonstrates that ACE inhibitory peptide LAP may lower blood pressure with no adverse effects.     

Enantioseparation and Determination of the Chiral Fungicide Furametpyr Enantiomers in Rice,Soil, and Water by High‐Performance Liquid Chromatography

The chiral fungicide furametpyr is widely used in the rice field to control rice sheath blight; however, furametpyr enantiomers are treated as just one compound in traditional achiral analysis, which gives only partial information. An effective chiral analytical method was developed for the resolution and determination of the fungicide furametpyr enantiomers in rice, soil, and water samples. Furametpyr enantiomers were excellently separated and determined on a Chiralpak AD‐H column with n‐hexane/ethanol (90:10, v/v) as mobile phase at a flow rate of 0.8 mL min^‐1 with UV detection at 220 nm. The resolution was up to 8.85. The first eluted enantiomer was (+)‐furametpyr and the second eluted one was (?)‐furametpyr. The effects of mobile‐phase composition and column temperature on the enantioseparation were evaluated. The method was validated for linearity, repeatability, accuracy, limit of detection (LOD), and limit of quantification LOQ. LOD was 2.0 µg kg^‐1 in water, 0.02 mg kg^‐1 in soil, and 0.07 mg kg^‐1 in rice with an LOQ of 6.7 µg kg^‐1 in water, 0.07 mg kg^‐1 in soil, and 0.23 mg kg^‐1 in rice. The average recoveries of the pesticide in all matrices ranged from 73.1 to 101.8% for all fortification levels. The precision values associated with the analytical method, expressed as relative standard deviation (RSD) values, were below 14.0% in all matrices. The methodology was successfully applied for the enantioselective analysis of furametpyr enantiomers in real samples. Chirality 25:904–909, 2013. © 2013 Wiley Periodicals, Inc.     

红曲色素β-环糊精包合物稳定性的初步研究

紫红曲霉经液体发酵可获得红曲色素 ,通过离心、过滤、乙醇浸提获得的发酵液中色素浓度为 0 .0 1 7g/mL。但其对光照、pH值、温度等不稳定限制了其用途。将 β 环糊精与所得色素包合 ,通过紫外扫描来初步表征包合物 ;并将包合物与游离色素放置在不同光照、pH值、温度条件下来比较各自的色泽保存率 ;结果表明 ,包合物与红曲色素相比 ,稳定性有一定程度的增强。