西番莲香味及主要糖酸物质含量的季节性变化规律研究

用改良的"Likens Nickerson"装置抽提出"华杨1号"黄果西番莲(Passifloraedulisf.flavicarpaDegener)果汁香精油,该香精油经GC MS分离鉴定出50种成分,包括脂肪族酯类16种,脂肪醇类6种,醛类5种,酮类5种,萜烯类13种,其他成分5种.丁酸乙酯、丁酸己酯、β 紫罗兰酮对西番莲果汁的香味贡献较大.西番莲果汁香味及主要糖酸物质含量存在显著的季节性差异.夏末初秋成熟的果实品质最佳:香味好,糖酸比高,丁酸乙酯、丁酸己酯和β 紫罗兰酮的含量高;冬季成熟的果实品质较差,但L-抗坏血酸含量较高.

Effects of Bagging with Paper Bags and Non-woven Bags on Flavor Compounds of Feicheng Peach

With Hongli Feicheng Peach as the test material, the effects of bagging with 4 kinds of paper bags and 3 kinds of non-woven bags on the soluble sugar, organic acids and aroma compounds in peach fruits were investigated using headspace solid-phase microextraction （HS-SPME） combined with gas chromatogra- phy-mass spectrometry （GC-MS） and high-performance liquid chromatography （HPLC）. The results showed that there were significant differences in sugar and acids contents of peach fruits between different bagging treatments. The sugar con- tent of peach fruits was increased when bagged with single-layer inner-black outer- yellow paper bags and double-layer inner-white outer-yellow paper bags. The organ- ic acid content in peach fruits bagged with all the types of bags except the single- layer inner-black outer-yellow paper bag was increased greatly. The count and rela- tive content of aroma compounds were all decreased after bagging. Combined with the detection results of soluble sugar, organic acids and aroma compounds, the sin- gle-layer inner-black outer-yellow paper bag was suitable for bagging of Hongli Fe- icheng peach.

The DNA damage response pathways： at the crossroad of protein modifications

Post-translational modifications play a crucial role in coordinating cellular response to DNA damage. Recent evidence suggests an interplay between multiple protein modifications, including phosphorylation, ubiquitylation, acetylation and sumoylation, that combine to propagate the DNA damage signal to elicit cell cycle arrest, DNA repair, apoptosis and senescence. Utility of specific post-translational modifiers allows temporal and spatial control over protein relo-calization and interactions, and may represent a means for trans-regulatory activation of protein activities. The ability to recognize these specific modifiers also underscores the capacity for signal amplification, a crucial step for the maintenance of genomic stability and tumor prevention. Here we have summarized recent findings that highlight the complexity of post-translational modifications in coordinating the DNA damage response, with emphasis on the DNA damage signaling cascade.

Assessing the Germplasm of Laminaria (Phaeophyceae) with Random Amplified PoLymorphic DNA (RAPD) Method

Eighteen gametophytes includingL. japonica, L. ochotensisandL. longissima, were verified with random amplified polymorphic DNA (RAPD) technique. Eighteen ten-base primers were chosen from 100 primers selected for final amplification test. Among the total of 205 bands amplified, 181 (88.3%) were polymorphic. The genetic distance among different strains ranged from 0.072 to 0.391. The dendrogram constructed by unweighted pair-group method with arithmetic (UPGMA) method showed that the female and male gametophytes of the same cell lines could be grouped in pairs respectively. It indicated that RAPD analysis could be used not only to distinguish different strains ofLaminaria, but also to distinguish male and female gametophyte within the same cell lines. There is ambiguous systematic relationship if judged merely by the present data. It seems that the use of RAPD marker is limited to elucidation of the phylogenetic relationship among the species ofLaminaria.

Metabolite identification and the development of a simultaneous quantification method for wogonin and wogonin-7-O-glucuronide:application to a distribution study in mice liver

Wogonin possesses potent inhibitory activities against cancer cell growth in vitro and in vivo and has attractive safety profiles.A highly sensitive liquid chromatography coupled with tandem mass spectrometry method was developed for the identification of major metabolites in mice liver after intravenous administration of wogonin.Five metabolites were identified and biotransformation pathways were elucidated as well.Furthermore,a method was developed and validated for the simultaneous quantitatively determination of wogonin and wogonin-7-O-glucuronide in mice liver.After liquid-liquid extraction by ethyl acetate,the analytes were separated on a C_（18）column with a mobile phase of methanol-10 mM ammonium acetate water （80：20,v/v）.The detection was operated with negative selected reaction monitoring mode using electrospray ionization technique. The linear response range was 0.2-40μg/g for both wogonin and wogonin-7-O-glucuronide in mice liver.The developed quantification method was suitable for distribution study after intravenous infusion of wogonin injection in animals.

A perspective on picornavirus inhibitors and concrete evolution of WIN compounds

The family Picornaviridae is one of the largest families of human viral pathogens,causing an extensive range of clinical manifestations from mild fever,common cold to serious paralytic poliomyelitis,COPD,etc.,some of which can even be life-threatening.Picornaviruses also cause zoonotic epidemics that result in dramatic social and economical losses.Although no efficient antivirus agent for prophylaxis or treatment of picornarivus infections has been officially approved yet,a large number of anti-picornavirus compounds with potent activity have been developed and investigated,through which further information about picornavirus has been revealed as well.Viral mRNA translation,viral mRNA replication and especially the viral capsid are the three main targets of these compounds having been extensively studied.The typical one is the WIN series of compounds that bind to the viral capsid and inhibit rival attachment or uncoating.Herein,a perspective on picornavirus inhibitors and a concrete evolution of WIN compounds will be presented in this paper.

Controlled synthesis of core-mesoporous shell from biomass sustainable N-doped hollow carbonaceous nanospheres

Encompassing ecological and economic concerns, the utilization of biomass to produce carbonaceous materials has attracted intensive research and industrial interest. Using nitrogen containing precursors could realize an in situ and homogeneous incorporation of nitrogen into the carbonaceous materials with a controlled process. Herein, N-doped hollow core-disordered mesoporous shell carbonaceous nanospheres （HCDMSs） were synthesized from glucosamine hydrochloride （GAH）, an applicable carbohydrate-based derivative. The obtained HCDMSs possessed controlled size （-450-50 nm） and shell thickness （-70-10 nm）, suitable nitrogen contents （-6.7-4.4 wt.%）, and Brunauer-Emmett-Teller （BET） surface areas up to 770 m^2.g^-1. These materials show excellent electrocatalytic activity as a metal-free catalyst for the oxygen reduction reaction （ORR） in both alkaline and acidic media. Specifically, the prepared HCDMS-1 exhibits a high diffusion-limited current, and superior durability and better immunity towards methanol crossover and CO poisoning for ORR in alkaline solution than a commercial 20 wt.% Pt/C catalyst.