曲酸及氯曲酸衍生物的合成及抑菌活性

以曲酸为原料,设计合成了16个曲酸衍生物(QI-01~QI-16)和10个氯曲酸衍生物(QII-01~QII-10),通过核磁共振氢谱及元素分析对其结构进行了表征。初步抑菌活性测定结果表明:所有供试化合物对苹果炭疽病菌Glomerella cingulata和番茄灰霉病菌Botrytis cinerea的菌丝生长均有不同程度的抑制作用,其中化合物QI-07和QI-11对苹果炭疽病菌活性最高,50μg/mL时的抑制率分别为79.3%和86.2%;化合物QII-04、QII-08和QII-09对番茄灰霉病菌活性最高,50μg/mL时的抑制率分别为70.0%、70.0%和76.7%。     

Investigating interactions of salicylic acid and jasmonic acid signaling pathways in monocots wheat

Upon pathogen or insect attack, plants respond with production of a specific blend of the alarm signals salicylic acid (SA) and jasmonic acid (JA), which are recognized as key players in the regulation of the signaling pathways involved. SA and JA responsive genes and SA/JA cross talk were well characterized in dicotyledonous species, but little is known in monocotyledonous plants. Using qRT-PCR, the expression profiles of SA and JA responsive genes were investigated after SA and JA treatments in monocots wheat. The results showed that Glu2 and PR-2 responded almost exclusively to SA, PR-3 and LOX2 responded positively to methyljasmonate (MeJA) treatment, while Lipase and PR-1.1 were induced in response to treatment with SA or MeJA. Furthermore, either by pathogen infection or exogenous application of hormones can activate the antagonistic effect between SA and JA in wheat, which has been well elucidated in dicotyledonous species. The outcomes of SA-JA interactions could be affected by the relative concentration of each hormone. This study shed light on marker genes that can represent SA and JA pathways in wheat and provided some clues for better understanding their interactions in monocot.     

苯甲酸·水杨酸·三唑酮混剂的液相色谱分析

本文介绍了以甲醇 水为流动相,采用C18不锈钢柱,230nm检测波长,对三唑酮、苯甲酸、水杨酸混合物进行液相色谱定量分析的方法。该方法的标准偏差分别为0．027、0．029、0．048;变异系数分别为0．24％、0．67％、0．74％;线性相关系数分别为0．9999、0．9999、0．9999;平均回收率分别为99．82％、100．39％、100．17％。     

黑松感染松材线虫后几种有机酸含量的变化

 Changes of benzoic acid, phenylacetic acid and salicylic acid contents in stem of 3-4 year old Pinus thunbergii inoculated with Bursaphelenchus xylophilus were studied by HPLC. The results showed that after nematode infection, contents of benzoic acid and salicylic acid in the stem of Pinus thunbergii increased gradually and then decreased when serious disease occurred, while content of phenylacetic acid increased at early stage and decreased at later stage of the disease. The role of benzoic acid, pbenylacetic acid and salicylic acid during the development of the disease was discussed.     

苯甲酸和肉桂酸促进蚕豆枯萎病发生的生理生化机制

为探讨苯甲酸和肉桂酸胁迫促进蚕豆枯萎病发生的生理生化机制,在接种蚕豆枯萎病菌Fusarium oxysporum f. sp. fabae的条件下,研究了苯甲酸和肉桂酸4个浓度处理对蚕豆枯萎病发生、植株抗氧化酶活性、膜质过氧化程度及病程相关蛋白的影响。结果表明,与对照相比,不同浓度苯甲酸处理下蚕豆枯萎病的病情指数提高了25.0%～362.5%;蚕豆根系和叶片中过氧化物酶(POD)活性分别降低了15.7%～31.4%和21.3%～38.7%,过氧化氢酶(CAT)活性分别降低了37.7%～42.8%和28.4%～44.8%,丙二醛(MDA)含量分别提高了28.9%～42.6%和16.4%～45.0%,根系几丁质酶和β-1,3-葡聚糖酶活性降低了23.6%～39.4%和17.4%～38.7%。与对照相比,不同浓度肉桂酸处理下蚕豆枯萎病的病情指数提高了37.5%～350.6%,蚕豆根系和叶片中POD活性分别降低了17.1%～48.6%和13.4%～36.0%,CAT活性分别降低了15.6%～61.0%和18.5%～57.9%,MDA含量分别提高了24.5%～51.8%和42.0%～94.1%,根系几丁质酶和β-1,3-葡聚糖酶活性分别降低了29.1%～48.9%和21.3%～40.2%。苯甲酸和肉桂酸浓度高于50 mg/L时显著降低蚕豆抗氧化酶性能,加剧细胞破损程度,抑制病程相关蛋白表达,降低自身生理生化抗性,有利于病原菌入侵,促进枯萎病发生,其中肉桂酸的促进效应大于苯甲酸。     

Comparative effects of two plant growth regulators; indole-3-acetic acid and chlorogenic acid on human and horse serum butyrylcholinesterase

Butyrylcholinesterase (BChE), a major detoxification enzyme found abundantly in many tissues and organisms, constitutes the first line defense in the serum of higher organisms and is a marker for toxic exposure. In this study, the interaction of two plant growth regulators, indole-3-acetic acid (IAA) and chlorogenic acid (CA) with purified human and horse serum BChE is investigated. The time dependent interaction of IAA with the two enzyme species was concentration dependent and rapid. Through kinetic studies, IAA was found to be linear-mixed type inhibitor for human serum BChE, and uncompetitive inhibitor for the horse serum enzyme. For the human BChE, α and the K_i value was calculated as 2.15 ± 1.09 and 3.09 ± 0.98 mM, respectively, and for the horse enzyme the K_i value was calculated as 1.05 ± 0.09 mM. The time dependent interaction of CA with the two enzyme species was biphasic. At low CA concentrations, CA stimulated the activities of both enzyme species whereas at high CA concentrations, inhibition was observed. At high concentrations, the inhibition kinetics for both enzymes fitted the non-competitive inhibition model. The K_i values calculated for human and horse BChE were 2.75 ± 0.14 and 0.96 ± 0.07 mM, respectively. The differences in the interaction of these two growth regulators with the two enzymes species arises from the structural differences between the human and horse serum BChE which can be considered as a triple human mutant BChE.     

茉莉酸对苹果幼树抗旱效应的研究

苹果幼苗经50mg/LJA处理4d后用PEG6000进行干旱胁迫。在胁迫的6h内，叶片气孔导度表现出“快—慢—快—慢”的降低趋势，相同浓度的JA与ABA使受旱植株叶片脯氨酸含量分别提高0.85mg/gFW～1.30mg/gFW和0.64mg/gFW～0.99mg/gFW，SOD活性分别提高1.08unit/(mg蛋白*min)～1.78unit/(mg蛋白*min)和0.89unit/(mg蛋白*min)～1.56unit/(mg蛋白*min)。相同浓度的JA的处理效应大于ABA。ABA预处理没有改变胁迫时叶片的MDA和内源ABA含量，而JA则使MDA含量降低0.01μmol/gFW～4.03μmol/gFW，ABA含量提高29ng/gFW～217ng/gFW。升高或降低的曲线均以4h为转折点。推测JA通过促进ABA合成而增强苹果对干旱的适应能力。     

芳甲酰氨基环丙酸的合成及其生物活性

以与脱落酸具有相同受体的化合物pyrabactin为先导,用1-氨基环丙酸替代2-氨甲基吡啶,设计合成了17个具有脱落酸功能的类似物(芳甲酰氨基环丙酸),其中13个为未经文献报道的新化合物。其结构均经过核磁共振氢谱、红外光谱和高分辨质谱(HRMS)确证。初步生物活性测试结果表明,大部分目标化合物表现出一定的延缓种子萌发活性,其中化合物 B4、B8和B11在5000μmol/L时的活性优于脱落酸。     

黄腐酸对乙草胺生物活性及持效期的影响

采用玉米根长法或芽长法研究了黄腐酸对乙草胺的生物活性、持效期和除草效果的影响.结果显示:乙草胺浓度和玉米根芽生长呈明显负线性关系,乙草胺浓度与根芽的线性方程为Y1=0.098x1+9.449和Y2=0.079x2+22.255,相关系数R1=-0.9916、R2=-0.9809;黄腐酸能够提高乙草胺的生物活性和除草效果,并延长乙草胺的持效期,添加0.25%～4.00%黄腐酸,乙草胺抑制玉米芽长和根长的活性分别提高7.12%～14.27%和6.32%～11.65%,其持效期延长0.46～12.17天:施药后28天,添加0.5%～2.0%的黄腐酸使乙草胺防除稗草的鲜重抑制率提高11.93%～16.88%.     

The phytotoxicity of natural tetramic acid derivatives

Natural tetramic acid derivatives have attracted a great deal of interest of chemists because of their structural features and the broad range of biological activities. This paper focuses on five naturally occurring tetramic acid derivatives reported to have phytotoxicity and discusses their common structural characteristics. Copyright © 2011 Society of Chemical Industry     

氨基酸补料对伊枯草菌素A发酵的影响

对枯草芽胞杆菌(Bacillus subtilis ZK8)进行4种不同工艺(分批发酵和3种氨基酸浓度的补料分批发酵)的发酵,测定并分析了发酵过程中各时间点样品中菌量、伊枯草菌素A (iturin A)的效价、还原糖、总氮及16种游离氨基酸的含量及变化趋势。结果表明,在工艺2 (补料浓度分别为天冬氨酸55 mg/L,谷氨酸12 mg/L,脯氨酸6 mg/L)发酵条件下,枯草芽胞杆菌ZK8菌量最高,达2.163×1010个/mL,比分批发酵(对照组)提高9.5%;在工艺1(补料浓度分别为天冬氨酸50 mg/L,谷氨酸9 mg/L,脯氨酸5 mg/L)发酵条件下,iturin A效价最高,达20 101.1 U,比对照提高了93.94%。     

嘧啶(氧)硫苯甲酸类除草剂研究进展

嘧啶(氧)硫苯甲酸类除草剂是超高效除草剂类型之一,是新一代绿色、安全、高效、低残留农药,具有很高的推广价值。本文综述了嘧啶(氧)硫苯甲酸类除草剂的主要类型、作用机理、国内外应用现状,总结了目前的研究进展;对其引发的杂草抗药性问题进行阐述。可为嘧啶(氧)硫酸苯甲酸类除草剂的农业应用及科学研究提供借鉴。     

小核盘菌菌丝生长和乙二酸合成影响因素研究

小核盘菌菌丝在V8溶液培养基和酵母浸膏溶液培养基中生长显著优于其他供试培养基,菌丝干重分别为6.666 mg/mL和6.632 mg/mL。在葡萄糖土豆浸汁培养基中产生的乙二酸量显著高于其他培养基,为1.981 mg/mL。在蔗糖液培养基中,培养7 d菌丝干重达到最大,为4.455 mg/mL。培养6 d乙二酸产生量达到最大,为0.966 mg/mL。培养基初始pH4.5最适合菌丝生长,干重为4.678 mg/mL。乙二酸含量随初始pH增加而增加,pH7.0的培养基中乙二酸含量为1.835 mg/mL。氮源含量增加可以促进乙二酸的合成,当蔗糖与大豆水解蛋白之比为25 g/10 g时,乙二酸含量为1.897 mg/mL。添加琥珀酸钠乙二酸含量显著增加,为3.741 mg/mL。     

子午岭不同植被类型土壤微生物量与有机酸含量

以黄土丘陵沟壑区的子午岭次生林区为研究区域,分析了农田、草本、乔木、灌木、弃耕地五种不同植被覆盖下土壤微生物量与有机酸含量变化。结果表明,不同植被类型土壤微生物生物量C变化趋势是:农田>草本>乔木>弃耕地>灌木,从乔木到农田微生物生物量N、P基本上呈下降趋势。不同植被类型下土壤有机酸变化基本趋势为:弃耕地<灌木<草本<农田<乔木。相关分析表明,不同植被覆盖下土壤微生量C、P与该土壤有机酸含量呈显著正相关,而土壤微生物N与该土壤有机酸含量相关性不显著。     

Plant extracts containing caffeic acid and rosmarinic acid inhibit zoospore germination of Phytophthora spp. pathogenic to Theobroma cacao

The three most important species of Phytophthora worldwide causing black pod disease of cacao are P. palmivora, P. megakarya, and P. capsici. Chemicals are effective in controlling this disease but more natural methods would be preferred. One alternative is to use natural plant extracts. Rosemary and lavender leaf extracts were found to be effective in reducing germination of P. capsici, P. megakarya, and P. palmivora zoospores when supplemented to agar plates at different dilutions. The extracts displayed the biggest impact on P. megakarya zoospores where it completely inhibited germination at a 25% dilution of the prepared extract. When applied to cacao leaf disks, rosemary extract reduced necrosis caused by P. megakarya zoospores. In a bioassay, pears first treated with lavender extract showed no symptoms of P. megakarya infection compared with the non-treated controls. Based upon HPLC analyses, the active compound in these extracts was determined to be caffeic acid, rosmarinic acid or some simple derivative thereof. When added to agar plates, synthetic caffeic acid and rosmarinic acid completely inhibited germination of P. capsici, P. megakarya, and P. palmivora zoospores at concentrations of 3 and 6 g l⁻¹, respectively. In addition, sage and rice bran extracts, which both contain caffeic acid, were also effective in reducing zoospore germination. In contrast, inhibition of Botrytis cinerea or Trichoderma asperellum conidia germination did not occur, displaying some level of specificity. These extracts could provide an economically safe method for reducing damage caused by black pod disease on cacao until resistant varieties are developed and released.     

植物源壬酸水剂对三裂叶豚草的防除效果

三裂叶豚草是危害生态环境和人类健康的恶性杂草。本研究探索了植物源壬酸水剂对野外自然生长的三裂叶豚草的防治效果,分别于6月下旬和8月上旬两个时期,利用5%和10%两个浓度的壬酸水剂对三裂叶豚草进行茎叶喷雾处理。结果表明,北京地区8月上旬为三裂叶豚草现蕾期,此时施药不再有新出苗的植株结籽,为防除三裂叶豚草的最适时期。采用10%壬酸水剂,有效成分用量8 000g/667m2,喷液量80L/667m2进行喷雾防治,7d和28d的株防效分别达到94.9%和91.2%,结籽三裂叶豚草仅4.6株/m2,比对照减少了93.11%,单株种子数量为261.78粒,比对照减少了83.73%,产生的种子少,防效较好。     

没食子酸对水稻细菌性条斑病防治作用的持效期

利用高效液相色谱法(HPLC)检测没食子酸(gallic acid,简称GA)在水稻叶片上的残留时间,并在检测水稻叶片上残留量的同时接种病原菌,调查接种后水稻细菌性条斑病的发病情况,以确定GA在水稻叶片上对水稻细菌性条斑病防治作用的持效期。研究结果表明,GA不具有内渗作用,只残留在水稻叶片的表面。分别用100、200和400 mg/L的浓度处理叶片后,GA在叶片表面的残留时间分别为16、24和28 d。200 mg/L浓度处理叶片后,GA对水稻细菌性条斑病防治作用的持效期为16 d。研究结果可为有效使用GA防治水稻细菌性条斑病奠定基础。     

Photochemical behaviour of dichlorprop [(+/-)-2-(2,4-dichlorophenoxy)propanoic acid] in aqueous solution

Aqueous solutions of dichlorprop were irradiated under different conditions of pH, wavelength and oxygenation. The photochemical behaviour was found to be complex and many photoproducts were formed. However, at low concentrations the main photoproducts were 4-chloropyrocatechol, 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol. Some other photoproducts were identified, namely 2-(4-chloro-2-hydroxyphenoxy)propanoic acid, 2-(3,5-dichloro-2-hydroxyphenyl)propanoic acid and 2,4-dichlorophenyl acetate. From comparison with results previously obtained with mecoprop [2-(4-chloro-2-methylphenoxy)propanoic acid] it appears that the presence of a chlorine atom in position 2 on the ring strongly modifies the photochemical behaviour.     

柠檬酸对石灰性土壤磷的释放效应

在盆栽条件下,以不施磷肥和不施柠檬酸为对照(CK1),研究了在不施磷和施磷情况下施用柠檬酸对土壤有效磷、小麦地上部和根部吸磷状况以及生物学产量的影响。结果表明,施用柠檬酸明显降低了土壤pH,增加了土壤中的有效磷的含量;在施用磷肥条件下,随着柠檬酸施用量的增加,土壤pH值逐步降低,土壤有效磷逐步提高,小麦地上部,尤其根部吸磷量增加,生物学产量显著增加。     

植物源羊脂酸除草活性及其响应机制

为研制新型植物源除草剂,需从植物中筛选具有除草活性的天然产物,本研究将椰子经物理压榨成椰子油,椰子油经皂化、酸化、蒸馏分段,再经气质联用仪鉴定其中具有除草活性的产物,并采用室内生测法和田间药效试验对该产物的除草活性进行评价,测定其在不同光照和浓度条件下对小飞蓬Conyza canadensis的3种防御酶——L-苯丙氨酸解氨酶、多酚氧化酶和过氧化物酶活性的影响。结果表明:从椰子油中筛选的具有除草活性的产物经鉴定为羊脂酸,气质色谱图中保留时间为6.20 min。羊脂酸具有较高的除草活性,EC_(50)为14.07 mg/L,100 m L的20%羊脂酸水乳剂喷施后15 d对20 m~2非耕地杂草的株防效和鲜重防效分别为90.25%和90.37%,即与对照药剂草甘膦异丙胺盐水剂除草效果相当。低浓度羊脂酸对小飞蓬的防御酶活性影响不显著,较高浓度下L-苯丙氨酸解氨酶活性显著上升,多酚氧化酶和过氧化物酶活性显著下降,当光强为100~120μmol·m~(-2)·s~(-1)、温度为18~20℃时,这种变化在完全黑暗条件下较完全光照条件下更为明显。表明羊脂酸除草机理可能与其抑制杂草的光合作用有关。