没食子酸对美国白蛾幼虫营养效应及解毒酶活性的影响

美国白蛾是我国重大外来入侵害虫,寄主范围十分广泛。酚类物质是最广泛的植物次生代谢物之一,在植物抵御昆虫取食的化学防御中具有重要作用。本研究通过人工饲料添加没食子酸的方法,探究不同浓度的没食子酸对美国白蛾幼虫的营养效应及解毒酶和乙酰胆碱酯酶活性的影响。结果表明,各浓度(1.0%、1.5%、2.0%、2.5%、3.0%)没食子酸对美国白蛾4龄幼虫的近似消化率、食物利用率、相对取食量和相对生长率均具有显著影响(P<0.05),近似消化率和相对取食量不同程度下降,食物利用率和相对生长率则不同程度上升。不同浓度的没食子酸处理对美国白蛾幼虫的乙酰胆碱酯酶、羧酸酯酶、谷胱甘肽S-转移酶和细胞色素P450的活性均具有显著影响(P<0.05)。1.0%没食子酸作用时间不同,美国白蛾4龄幼虫的乙酰胆碱酯酶、羧酸酯酶、谷胱甘肽S-转移酶和细胞色素P450的活性差异显著(P<0.05)。没食子酸能够始终诱导细胞色素P450的活性,而羧酸酯酶的活性却受到抑制。不同浓度的没食子酸对乙酰胆碱酯酶作用总体上不明显,但较低浓度时(1.0%)对乙酰胆碱酯酶活性却随处理时间延长而抑制作用加强。较低浓度(1.0%~1.5%)的没食子酸对谷胱甘肽S-转移酶的活性有一定诱导作用,但随着没食子酸浓度提高谷胱甘肽S-转移酶的活性却受到一定程度的抑制。没食子酸能抑制美国白蛾幼虫的取食,并且对解毒酶和乙酰胆碱酯酶的活性表现出一定的时间效应和剂量效应,表明美国白蛾幼虫可能通过调节食物利用和解毒代谢等多种途径降低没食子酸的毒害作用,从而对含没食子酸的寄主植物产生适应。     

不同小麦品种（系）对麦长管蚜的抗性

采用网罩麦长管蚜Sitobion miscanthi (Takahashi)的观测方法,对15个不同抗性小麦品种（系）进行苗期不选择性、抗生性测定;选择其中5个代表性品种（系）观测了田间扬花期麦长管蚜的产蚜量,测定了小麦旗叶和穗部中单宁与槲皮素的含量以及麦长管蚜羧酸酯酶（CarE）与谷胱甘肽S-转移酶（GST）的活性。结果表明,代表性品种（系）在苗期对麦长管蚜的产蚜量的影响与扬花期的呈显著正相关（r＝0.956*）。穗部槲皮素的含量与不同抗性品种（系）上的产蚜量呈显著负相关（r＝-0.941*）;单宁含量在不同抗性品种（系）间存在显著差异,其含量变化与产蚜量无显著相关。取食不同抗性品种（系）后麦长管蚜的CarE和GST酶活力存在显著差异。结论认为小麦不同品种（系）对麦长管蚜产蚜量（生殖力）的抑制作用是其抗蚜的重要特性,尤其是中4无芒和冀保一号对麦长管蚜抗生性较强。     

茄无网蚜几种酶对溴氰菊酯与高温胁迫的应答

[目的]通过研究茄无网蚜Acyrthosiphon solani(Kaltenbach)在溴氰菊酯和高温2种胁迫方式下其单位虫体质量解毒酶、保护酶和代谢酶活力的变化情况,为茄无网蚜耐药性研究、发生期预测等提供相应的理论依据.[方法]本文用LC50溴氰菊酯和32℃高温分别胁迫3龄茄无网蚜6、12、24、48和72 h,分析并比较其单位虫体质量谷胱甘肽-S-转移酶、过氧化物酶、羧酸酯酶和海藻糖酶的活力变化.[结果]过氧化物酶和羧酸酯酶对2种胁迫方式的响应剧烈,单位虫体质量的过氧化物酶活力在茄无网蚜被溴氰菊酯胁迫6、24和48 h后被显著抑制(P＜0.05),在温度胁迫处理组中均高于对照组,且在6、12和24 h处理组差异显著(P＜0.05);羧酸酯酶活力在溴氰菊酯胁迫时有较大波动,在6、24、48和72 h处理组与对照差异显著(P＜0.05).海藻糖酶对2种胁迫方式的响应较剧烈,海藻糖酶活力在溴氰菊酯胁迫6、24、48和72 h处理组显著高于对照(P＜0.05),在温度胁迫6、12和72 h处理组与对照组差异显著(P＜0.05).谷胱甘肽-S-转移酶对2种胁迫方式的响应相对较弱,谷胱甘肽-S-转移酶活力仅在溴氰菊酯胁迫6h和24 h处理组与温度胁迫24 h处理组显著高于对照(P＜0.05).[结论]LC50溴氰菊酯胁迫比温度胁迫对茄无网蚜体内4种酶活力的影响更大;2种胁迫方式对茄元网蚜体内4种酶活性均产生影响,过氧化物酶与羧酸酯酶参与度更高.     

槲皮素对B型烟粉虱羧酸酯酶和谷胱甘肽S-转移酶活性的影响

采用人工饲料添加法,研究植物防御性次生物质槲皮素对B型烟粉虱Bemisiatabaci(Gennadius)成虫主要解毒酶系羧酸酯酶(CarE)和谷胱甘肽S-转移酶(GSTs)影响的剂量效应和时间效应。用低剂量槲皮素(0.01%,wv)处理B型烟粉虱成虫24h后,其羧酸酯酶(CarE)和谷胱甘肽S-转移酶(GSTs)比活力分别为51.09mOD(min·头)和2.249OD(mgpro.min),是对照的1.233倍和2.20倍;而高剂量的槲皮素对2种解毒酶没有诱导增加作用,甚至还有抑制作用。低剂量的槲皮素短时间处理烟粉虱后,可诱导2种酶活性增加,谷胱甘肽S-转移酶(GSTs)在0.005%的槲皮素处理30min后,比活力值达到8.454OD(mgpro·min),为对照的8.30倍。     

四种类型杀虫剂对麦长管蚜的温度效应及其与主要解毒酶的关系

为了明确杀虫剂毒力受温度的影响及其程度,本文测定了4大类8种药剂在10～25℃下对麦长管蚜的毒力;并测定了麦长管蚜Sitobion avenae(Fabricius)在不同温度下2个解毒酶和1个靶标酶的活性差异。结果表明,高效氯氰菊酯对麦长管蚜表现不规则负温度系数,啶虫脒表现不规则正温度系数,高效氟氯氰菊酯对麦长管蚜的毒力不受温度影响,其他药剂(辛硫磷、毒死蜱、灭多威、丁硫克百威、吡虫啉)均表现为明显的正温度系数效应,以有机磷类杀虫剂表现最为明显,毒死蜱温度系数高达57.70。酶活性实验表明:麦长管蚜在高温下GST活性增强,羧酸酯酶和乙酰胆碱酯酶活性降低。它们的变化规律表明:GST活性与负温度系数密切相关,正温度系数与羧酸酯酶活性和靶标酶乙酰胆碱酯酶活性有关。     

麦长管蚜羧酸酯酶基因cDNA片段克隆及吡虫啉胁迫对其表达的影响

羧酸酯酶在昆虫对杀虫剂的解毒代谢过程中发挥重要作用,本研究旨在分析吡虫啉胁迫对麦长管蚜羧酸酯酶基因表达的影响。采用同源克隆方法克隆麦长管蚜羧酸酯酶基因cDNA片段,实时荧光定量PCR技术检测羧酸酯酶基因在不同吡虫啉剂量下的表达量变化。扩增所得麦长管蚜羧酸酯酶基因cDNA片段大小为392 bp,命名为SaEST 3(GenBank登录号KY 441614),该片段编码130个氨基酸残基,分子量14 kD,等电点4.93。序列同源性比对及生物信息学分析表明SaEST3推导的氨基酸序列与豌豆长管蚜、麦双尾蚜、夹竹桃蚜、桃蚜的羧酸酯酶氨基酸序列相似性较高,分别为94%、85%、80%和80%。实时荧光定量PCR结果显示,不同吡虫啉处理剂量下,SaEST3 m RNA的相对表达量均上调。克隆得到的基因片段为麦长管蚜羧酸酯酶基因片段,吡虫啉对麦长管蚜羧酸酯酶基因SaEST3表达有一定的影响。     

麦长管蚜唾液中几种酶的鉴定、活力测定与功能分析

用Parafilm膜夹营养液法,以两种食料介质饲喂麦长管蚜Macrosiphum avenae 3龄若蚜并收集其唾液,对唾液中的酶类进行了鉴定、活力测定和功能分析。结果表明,在20%蔗糖介质提取液中,鉴定有果胶酶、多酚氧化酶和纤维素酶; 在水介质提取液中鉴定有纤维素酶; 两种介质提取液中都未鉴定出过氧化物酶。酶活力测定结果表明, 在20%蔗糖介质提取液中, 每30头蚜虫分泌的果胶酶、多酚氧化酶和纤维素酶的酶活力分别为2.59×10^-3 U/g、7×10^-3 U/g和7.89×10^-3 U/g; 在水介质提取液中,纤维素酶活力为3.68×10^-3 U/g。行为反应试验结果表明,果胶酶处理麦苗的挥发物组分能引起麦长管蚜寄生性天敌燕麦蚜茧蜂Aphidius avenae和捕食性天敌七星瓢虫Coccinella septempunctata 的嗅觉偏好反应,因此,果胶酶在麦长管蚜取食诱导小麦植株的间接防御反应中具有重要作用。     

两种体色生物型桃蚜对杀虫剂敏感性差异及其与酶活力的关系

为了明确不同体色生物型桃蚜Myzus persicae (Suizer)对药剂的敏感性差异,本文采用室内生物测定和酶活力测定法检测不同体色生物型桃蚜对杀虫剂的敏感性以及与3种解毒酶和1种靶标酶活力关系。结果表明,红色生物型的敏感性明显低于绿色生物型,其中对吡虫啉的敏感性差异最大,LC50分别为6796648和284597 mg/L,红色为绿色生物型2388倍;其次为毒死蜱,LC50分别为12295798和1936816 mg/L,红色为绿色生物型635倍;两种生物型桃蚜对阿维菌素敏感性差异最小,红、绿色生物型的LC50分别为311678 和290966 mg/L,红色为绿色生物型107倍。红色生物型体内3种解毒酶（羧酸酯酶、谷胱甘肽-S-转移酶和多功能氧化酶P450）的比活力均高于绿色生物型,红色型羧酸酯酶比活力为绿色型的31倍,谷胱甘肽-S-转移酶为41倍,多功能氧化酶P450为15倍,两种体色生物型3种解毒酶的活力差异均达显著水平。两种体色生物型体内乙酰胆碱酯酶比活力没有差异,说明乙酰胆碱酯酶比活力与敏感性关系不大。     

棉蚜抗吡虫啉品系和敏感品系主要解毒酶活性比较

通过生物测定和生物化学方法比较了棉蚜 Aphis gossypii 对吡虫啉抗性（约为7倍）和敏感品系几种主要解毒酶的活性。结果表明：氧化胡椒基丁醚对两个品系均无明显增效作用。抗性品系中羧酸酯酶和谷胱甘肽S-转移酶的比活力均明显高于敏感品系,抗性品系中羧酸酯酶的K_m值也显著高于敏感品系,说明抗性品系羧酸酯酶与底物的亲和力明显高于敏感品系。上述结果证明羧酸酯酶和谷胱甘肽S-转移酶活力增强在棉蚜对吡虫啉的抗性中起重要作用。     

6种植物次生物质对斜纹夜蛾解毒酶活性的影响

草食性昆虫取食植物时遇到宿主植物中大量次生物质的化学防御,研究昆虫适应植物毒素的反防御策略具有重要的科学意义。分别添加0.01%肉桂酸、0.01%水杨酸、0.01%花椒毒素、0.02%槲皮素、0.05%黄酮和0.1%香豆素等6种植物次生物质的人工饲料饲养斜纹夜蛾(Spodoptera litura)五龄幼虫48 h后,测定斜纹夜蛾幼虫中肠和脂肪体中谷胱甘肽S-转移酶(GSTs)、羧酸酯酶(CarE)、P450的酶含量及头部乙酰胆碱酯酶(AChE)的活性,利用半定量RT-PCR检测中肠和脂肪体中CYP4M14和CYP4S9的基因表达水平。结果表明:取食肉桂酸和香豆素后,斜纹夜蛾中肠中CarE的酶活性分别提高了1.67和1.37倍,取食6种次生物质均能显著提高斜纹夜蛾脂肪体中GSTs酶活性。取食肉桂酸和香豆素48 h后,脂肪体中P450酶含量比对照增加2.93和14.50倍。取食肉桂酸、花椒毒素、槲皮素和香豆素后,斜纹夜蛾头部AchE酶活性与对照相比提高了1.53、1.80、2.36和1.56倍。6种次生物质均可诱导脂肪体中CYP4M14基因表达,槲皮素、肉桂酸和香豆素强烈诱导CYP4S9在脂肪体中表达。表明,斜纹夜蛾具有利用植物次生物质诱导其解毒酶的能力,进而提高其对毒素的抗性。     

枣花病对意大利蜜蜂消化酶和解毒酶系活性的影响

[目的]枣花期蜜蜂易发生枣花中毒(又称枣花病),致使大量采集蜂死亡.本研究初步探讨了枣花病对蜜蜂的毒性作用机理.[方法]以正常的意大利蜜蜂Apis mellifera ligustica工蜂为对照,采用分光光度法测定山西临猗、太谷和临县患枣花病的意大利蜜蜂工蜂体内淀粉酶、蛋白酶、蔗糖酶、果胶酶、海藻糖酶、酯酶(este...     

斑蝥素对粘虫几种代谢酶及多酚氧化酶的影响

为进一步探讨斑蝥素的杀虫作用机理, 本研究采用叶碟饲喂法处理粘虫Mythimna separata（Walker）5龄幼虫, 测定了饲喂处理后6, 12, 24, 36和48 h试虫体内羧酸酯酶(CarE)、酸性磷酸酯酶(ACP)、碱性磷酸酯酶(ALP)、谷胱甘肽 S-转移酶(GST)和细胞色素P450 Ο-脱甲基酶及多酚氧化酶(PPO)的活性。结果表明: 斑蝥素可显著激活羧酸酯酶, 处理后48 h酶比活力最大, 为同期对照的1.68倍; 酸性磷酸酯酶在处理后6和12 h活性变化不明显, 处理24 h后逐渐被激活, 且与对照差异显著(P＜0.05); 明显抑制碱性磷酸酯酶, 且随着处理时间的延长, 抑制作用增强; 对Ο-脱甲基酶表现为先抑制后激活的趋势; 谷胱甘肽S-转移酶表现出先激活后抑制的影响; 离体活体条件下均可显著抑制PPO活性。可见, 斑蝥素可明显影响昆虫的代谢酶系, 且其对碱性磷酸酶和多酚氧化酶的抑制作用可能与其毒杀作用有关。     

Effect of tannic acid on brush border disaccharidases in mammalian intestine

Tannic acid is a glucoside (penta-m-digallolyl-glucose), which exhibits a wide variety of physiological functions. Around neutral pH, 0.4 mM tannic acid produced 84% inhibition of rat brush border sucrase activity, but 35-40% enzyme inhibition was observed in the rabbit intestine at 0.08 mM concentration. In the mice, 74-77% enzyme inhibition was observed at 0.05 mM concentration of tannic acid. The observed inhibition was reversible in rat intestine. Tannic acid (0.2 mM) also inhibited lactase (18% in adult and 71% in suckling animals), maltase (76%) and trehalase (88%) activities in rat intestine. pH versus activity curves showed that 0.2 mM tannic acid inhibited enzyme activity in rat by 91% at pH 5.5 which was reduced to 14% at pH 8.5 compared to the respective controls. In the rabbit 18-60% enzyme inhibition was noticed below pH 7.0, however at pH 8.5, it was of the order of 38%. Kinetic analysis revealed that tannic acid is a competitive inhibitor of rat brush border sucrase at pH 6.8. Effect of tannic acid together with various -SH group reacting reagents revealed that the enzyme inhibition is additive in nature, suggesting the distinct nature of binding sites on the enzyme for these compounds. The results suggest that tannic acid is a potent inhibitor of intestinal brush border disaccharidases, and could modulate the intestinal functions.     

Purification and characterization of acid trehalase from the yeast suc2 mutant

Acid trehalase was purified from the yeast suc2 deletion mutant. After hydrophobic interaction chromatography, the enzyme could be purified to a single band or peak by a further step of either polyacrylamide gel electrophoresis, gel filtration, or isoelectric focusing. An apparent molecular mass of 218,000 Da was calculated from gel filtration. Polyacrylamide gel electrophoresis of the purified enzyme in the presence of sodium dodecyl sulfate suggested a molecular mass of 216,000 Da. Endoglycosidase H digestion of the purified enzyme resulted after sodium dodecyl sulfate gel electrophoresis in one distinct band at 41,000 Da, representing the mannose-free protein moiety of acid trehalase. The carbohydrate content of the enzyme was 86%. Amino acid analysis indicated 354 residues/molecule of enzyme including 9 cysteine moieties and only 1 methionine. The isoelectric point of the enzyme was estimated by gel electrofocusing to be approximately 4.7. The catalytic activity showed a maximum at pH 4.5. The activity of the enzyme was not inhibited by 10 mM each of HgCl2, EDTA, iodoacetic acid, phenanthrolinium chloride or phenylmethylsulfonyl fluoride. There was no activation by divalent metal ions. The acid trehalase exhibited an apparent Km for trehalose of 4.7 +/- 0.1 mM and a Vmax of 99 mumol of trehalose min-1 X mg-1 at 37 degrees C and pH 4.5. The acid trehalase is located in the vacuoles. The rabbit antiserum raised against acid trehalase exhibited strong cross-reaction with purified invertase. These cross-reactions were removed by affinity chromatography using invertase coupled to CNBr-activated Sepharose 4B. Precipitation of acid trehalase activity was observed with the purified antiserum.     

阿特拉津和敌敌畏对棉铃虫和家蝇羧酸酯酶以及GSH—S—转移酶的诱导作用

在一定时间内,刚特拉津 (Atrazinc)对棉铃虫 Heliothis armigera 幼虫羧酸酯酶以及GSH-S-转移酶(GST)活性有明显的诱导作用,羧酸酯酶活性最高增加146%,GST增加280%。 对羧酸酯酶的诱导高峰时间要落后于GST,不同施药剂量的诱导高峰时间以及导增加的量也不相同。 敌敌畏对家蝇Musca domestica vicina GST活性没有明显的诱导作用,阿特拉津对家蝇GST活性也没有产生诱导作用。     

Effect of Three Phenolic Compounds on Hill Activity in Rice (Oryza sativa)

The role of phenolic compounds in regulating the Hill activityin the flag leaf of rice during grain development has been studied.Salicylic acid (25 ppm), caffeic acid (25 ppm) and tannic acid(50 ppm) have been found to be the most effective concentrationsto increase the activity of this system. Salicylic acid, caffeic acid, tannic acid, Hill activity     

Depressed performance and detoxification enzyme activities of Helicoverpa armigera fed with conventional cotton foliage subjected to methyl jasmonate exposure

Methyl jasmonate (MeJA)‐mediated defense in conventional cotton, Gossypium hirsutum L. (Malvaceae), against cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), was investigated with respect to the activities of the detoxification enzymes acetylcholinesterase (AChE), carboxylesterase (CarE), and glutathione S‐transferases (GST) in pupae as well as the performance of larvae. The results suggested that exogenous application of MeJA to cotton leaves depressed the activities of AChE, CarE, and GST of cotton bollworm pupae. Both the absolute and protein‐specific AChE activities of pupae were depressed at all three MeJA concentrations applied as compared with a control, and the effects of 0.4 mM MeJA were significantly higher than those of 0.1 and 0.2 mM. A marked reduction in absolute CarE activity was observed at the 0.4 mM MeJA treatment, whereas the protein‐specific activity was increased by 0.2 and 0.4 mM. Absolute GST activity was significantly depressed only by the 0.4 mM MeJA treatment, whereas protein‐specific GST activity was not markedly affected by MeJA. Protein content of pupae was reduced by 0.4 mM MeJA‐induced defense in cotton leaves. The development time of larvae was protracted and pupal weight was reduced by 0.1 and 0.4 mM MeJA‐treated cotton leaves. Larval weight gain was inhibited significantly on 0.2 and 0.4 mM MeJA‐treated cotton leaves. The results suggested that MeJA‐induced plant defense may have adverse effects on H. armigera. In addition to the inhibition of growth and development, induced defense may also impair the insect's ability to detoxify toxic plant secondary metabolites.     

高温对田间小菜蛾DNA损伤及4种抗药性相关酶系活性的抑制

研究了高温对福州上街菜田小菜蛾成虫4种抗药性相关酶系活性的影响。与饲养在25℃下的小菜蛾相比,33．5~C或40℃处理72h导致小菜蛾基因组DNA出现DNA凋亡特征梯度化条带。33~C饲养小菜蛾4、8、12或24h对小菜蛾成虫乙酰胆碱酯酶（AChE）和羧酸酯酶（CarE）活性无显著影响,但33℃饲养小菜蛾12或24h导致小菜蛾成虫谷胱甘肽s转移酶（GSTs）酶活性和细胞色素P450含量显著下降。36℃、24h可导致AChE活性显著下降,36℃、12h和24h可导致CarE活性显著下降,36℃、4h,8h,12h和24h可导致GST活性和细胞色素P450含量显著下降。总体上,高温对CarE、GSTs和细胞色素P450的抑制作用大于对AChE的影响,此外,3CC对AChE、CarE、GSTs酶活性和细胞色素P450含量的抑制作用大于33℃的抑制作用。     

Effect of phenolic compounds on protein cross-linking and properties of film from fish myofibrillar protein

The effects of several phenolic ocmpounds (caffeic acid, catechin, ferullic acid and tannic acid) at various concentrations (1, 3 and 5% based on protein) on cross-linking and properties of film from myofibrillar proteins of bigeye snapper (Priacanthus tayenus) were investigated. Among all phenolic compounds used, tannic acid exhibited the highest cross-linking ability on myofibrillar protein as evidenced by higher decrease in free amino groups with coincidentally lower band intensity of myosin heavy chain (MHC). In addition, the extent of protein cross-linking increased with increasing concentration of phenolic compounds. Addition of phenolic compounds could enhance mechanical properties of the resulting films. As phenolic compounds content increased, Young's modulus (E) and tensile strength (TS) of the films increased, while their elongation at break (EAB) decreased (P<0.05), suggesting stronger and stiffer film structure. At the same concentration used, tannic acid rendered the film with higher mechanical properties, compared to others. Phenolic compounds decreased film transparency and affected color of the films differently, depending on types and concentrations used. Films from myofibrillar proteins with and without polyphenol generally had the excellent barrier properties to UV light at the wavelength of 200-800nm. Therefore, it could potentially be used as inner packaging material for high-fat foods to prevent the lipid oxidation and thus prolonging the shelf-life of foods during storage.