添加剂对堆肥过程中挥发性有机物（VOCs）的减排效果

为明确添加剂对堆肥挥发性有机物（Volatile organic compounds,VOCs）排放的减排效果和影响因素,通过文献筛选出吸附类添加剂（活性炭和沸石）与有机酸类添加剂（柠檬酸和草酸）开展实验研究。在鸡粪-玉米秸秆堆肥实验中,设置5个处理,分别为对照（CK）、添加活性炭、添加沸石、添加柠檬酸和添加草酸处理。研究对象包括115种VOCs、三甲胺和6种含硫有机挥发气体（二甲硫醚、二甲基二硫醚、二甲基三硫醚、甲硫醇、乙硫醇、乙硫醚）。结果表明：在28 d的好氧发酵中,所有处理均达到50 ℃并维持7 d,满足无害化标准。检出110种VOCs、三甲胺和3种含硫有机挥发气体（二甲硫醚、二甲基二硫醚,二甲基三硫醚）。VOCs的排放集中在前9 d,在第3天时VOCs达到峰值。5个处理在堆肥第3天检测到的VOCs浓度范围为169.22~548.26 mg·m^-3。4种添加剂对各类VOCs均有减排效果。在第3天,活性炭、沸石、柠檬酸和草酸对烷烃类的减排效率分别为79%、26%、77%和46%,对卤烃类的减排效率分别为96%、38%、93%和97%,对芳香烃类的减排效率分别为28%、11%、24%和53%。从堆肥第6天开始只有沸石对各类VOCs有减排效果,最高减排效率为30%。针对含硫有机挥发气体减排,减排效果依次是草酸>柠檬酸>沸石>活性炭。4种添加剂对含硫有机挥发气体均有减排效果,但是对三甲胺没有减排效果。综合堆肥前9 d VOCs的减排情况,4种添加剂中沸石对各类VOCs减排效果最好。堆肥过程中添加沸石有利于VOCs和其他气体的协同减排,并且对土壤和农作物不存在风险,所以沸石在堆肥工程中有广阔的应用前景。     

Approaches to Configuration Determinations of Flexible Marine Natural Products: Advances and Prospects

Flexible marine natural products (MNPs), such as eribulin and bryostatin, play an important role in the development of modern marine drugs. However, due to the multiple chiral centers and geometrical uncertainty of flexible systems, configuration determinations of flexible MNPs face great challenges, which, in turn, have led to obstacles in druggability research. To resolve this issue, the comprehensive use of multiple methods is necessary. Additionally, configuration assignment methods, such as X-ray single-crystal diffraction (crystalline derivatives, crystallization chaperones, and crystalline sponges), NMR-based methods (JBCA and Mosher’s method), circular dichroism-based methods (ECCD and ICD), quantum computational chemistry-based methods (NMR calculations, ECD calculations, and VCD calculations), and chemical transformation-based methods should be summarized. This paper reviews the basic principles, characteristics, and applicability of the methods mentioned above as well as application examples to broaden the research and applications of these methods and to provide a reference for the configuration determinations of flexible MNPs.     

饲料分析检验过程的质量保证与控制

在饲料分析检验过程中不可避免产生系统和随机误差,从而影响分析结果的准确度。系统误差是由于检验过程中某些确定的、经常性的原因所造成的误差．它对检验结果的影响比较固定．在重复检验过程中可以重复地表现出来．系统误差产生的原因和来源主要包括仪器误差、试剂误差、测定方法误差、分析人员个人误差等。随机误差是由于一些偶然的外部因素所引起的．产生随机误差的因素不定。     

Taxonomic and Bioactivity Characterizations of Mameliella alba Strain LZ-28 Isolated from Highly Toxic Marine Dinoflagellate Alexandrium catenella LZT09

Microalgae host varied microbial consortium harboring cross-kingdom interactions with fundamental ecological significance in aquatic ecosystems. Revealing the complex biofunctions of the cultivable bacteria of phycosphere microbiota is one vital basis for deeply understanding the mechanisms governing these dynamic associations. In this study, a new light-yellow pigmented bacterial strain LZ-28 was isolated from the highly-toxic and harmful algal bloom-forming dinoflagellate Alexandrium catenella LZT09. Collective phenotypic and genotypic profiles were obtained to confidently identify this strain as a new Mameliella alba member. Comparative genomic analysis showed that strain LZ-28 shared highly similar functional features with other four marine algae-derived M. alba strains in spite of their distinctive isolation sources. Based on the bioactivity assaying, the mutual growth-promoting effects between bacterial strain LZ-28 and algal strain LZT09 were observed. After the culture conditions were optimized, strain LZ-28 demonstrated an extraordinary production ability for its bioflocculanting exopolysaccharides (EPS). Moreover, the portions of two monosaccharides glucose and fucose of the EPS were found to positively contribute to the bioflocculanting capacity. Therefore, the present study sheds light on the similar genomic features among the selected M. alba strains, and it also reveals the potential pharmaceutical, environmental and biotechnological implications of active EPS produced by this new Mameliella alba strain LZ-28 recovered from toxic bloom-forming marine dinoflagellate.     

基于非靶向代谢组学的特色寒地浆果滋味品质分析

为探究笃斯越橘、蓝靛果、树莓、黑加仑4种特色寒地浆果滋味特点,及其滋味形成的特征性物质组成,该研究基于超高效液相色谱-四极杆飞行时间质谱（ultra-high-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry, UPLC-QTOF-MS）和气相色谱质谱法（gaschromatography-mass spectrometry, GC-MS）分别对4种浆果的非挥发性和挥发性物质进行鉴定和筛选,并进行公因子分析;同时进行4种浆果的电子舌分析及感官评价,得出4种浆果滋味品质模糊综合得分。结果显示：笃斯越橘糖酸比为4.41,特征性挥发性物质为α-松油醇和苯甲醛,电子舌酸味响应值最强;黑加仑糖酸比为3.80,特征性挥发性物质为苯乙醇和乙酸,各滋味响应值相当;蓝靛果糖酸比为3.37,总酚含量最高,特征性挥发性物质为正己醇和3-己烯-1-醇,咸味和鲜味响应值最高;树莓糖酸比为8.19,特征性挥发性物质为乙酸和α-紫罗酮,甜味和苦味响应值最高;经筛选鉴定及统计分析得出4种浆果的非挥发性物质中有显著差异的化合物有10种,分别为塔格糖、乳酸、阿洛酮糖、草酸、柠檬酸、天冬氨酸、茜草苷、6α-甘露二糖、蔗糖和异槲皮素。滋味感官模糊综合评分由大到小为树莓、蓝靛果、笃斯越橘、黑加仑;因子分析结果表明4种浆果滋味组成得分由大到小排序依次为黑加仑、蓝靛果、笃斯越橘和树莓。该研究结果可为4种寒地浆果的产品开发滋味调控提供理论依据。     

新型饲料添加剂——碱式氯化锌的合成及性质研究

以氯化锌和氧化锌为原料,合成了一种新型饲料添加剂——碱式氯化锌[Zn5(OH)8Cl2·H2O,TBZC]。采用正交试验法,研究了反应温度、反应时间、反应液pH值、干燥温度对TBZC合成的影响,确定了最佳合成条件:氯化锌和氧化锌摩尔比1:4、反应液pH值5.5、反应温度90℃、反应时间2.5h、干燥温度80℃、干燥时间2h,产率可达88%。借助XRD、IR、DSC确定其结构。通过对TBZC的吸水性、溶解性进行试验,结果表明,TBZC具有不吸湿、不溶于水、易溶于酸性和中性盐溶液的性质。     

樱桃小茎尖培养后的早熟变异与RAPD鉴定

樱桃品种Ｘｅｓｐｈｙｅ（Ｐｒｕｎｕｓ　ａｖｉｕｍ）的休眠芽通过小茎尖分生组织培养后,发现一株组培苗结果后成熟期明显早于Ｘｅｓｐｈｙｅ及同批其它试管苗,该株经无性繁殖试栽后早熟性状稳定,并且综合性状良好,具栽培价值,暂定名“早丹”。经ＲＡＰＤ技术鉴定,该早熟变异株的ＤＮＡ指纹图谱与原Ｘｅｓｐｈｙｅ品种不同,早熟变异株比原 Ｘｅｓｐｈｙｅ品种多扩增一条 ＯＰＵ０３－９５０ ＤＮＡ谱带,说明该株系发生了ＤＮＡ的变异。     

聚类分析在我国果树研究中的应用及问题分析

对近１０年来聚类分析在我国果树研究中的应用情况进行了简要总结。涉及十余种果树及系统聚类和模糊聚类两种聚类分析方法。文中对有关问题进行了分析和讨论。     

不结球白菜维生素C和可溶性糖含量的遗传分析

采用主基因—多基因混合遗传模型分析方法,对不结球白菜乌塌菜×矮脚黄、雪克青×矮脚黄两个组合的维生素Ｃ、可溶性糖含量进行单世代和联合世代遗传分析。结果表明,两组合中维生素Ｃ含量遗传符合一个主基因和多基因的混合遗传模型,主基因遗传率为５２６８％～７４１２％。可溶性糖在雪克青×矮脚黄组合中也符合主基因—多基因遗传模型,主基因遗传率为８９７３％～８９７９％。维生素Ｃ和可溶性糖主基因效应均以加性效应为主,在乌塌菜×矮脚黄组合中,两性状主基因有较明显的负向显性效应,在雪克青×矮脚黄组合中,显性效应不明显。育种实践中应注重对主基因加性效应的利用。