枸杞子水提物对采绒革盖菌木质纤维素酶和木质素酶活性的影响

以梯度试验方法研究了采绒革盖菌（Ｃｏｒｉｏｌｕｓ ｖｅｒｓｉｃｏｌｏｒ）在含不同量枸杞子（Ｌｙｃｉｕｍ ｃｈｉｎｅｎｓｅ）水煎液的ＰＤＹ液体培养基中生长时,纤维素酶、半纤维素酶、木质素酶（漆酶、邻苯二酚氧化酶、愈创木酚氧化酶）活性的变化。结果表明,培养基中含有４％￣５％的枸杞子水提物能明显促进菌丝体生长,显著增强胞内和胞外酶活性。     

糙皮侧耳多糖分解酶和木质素酶活性研究

本文测定了侧耳在ＰＤＹ培养液中生长时，培养液ＰＨ值的变化，蛋白质含量和菌丝体研究了淀粉酶，羧甲基纤维素酶，半纤维素酶，邻苯二酚氧化酶，愈创木酚氧化酶和漆酶的活性变化。结果表明；在整个培养欺内六种酶均有酶活性，但不同酶的活性有较大差异，产酶高峰也不尽相同。     

金耳液体培养过程中几种胞外酶活性的变化规律

测定了金耳液体培养过程中,培养基中的淀粉酶、羧甲基纤维素酶、半纤维素酶、果胶酶、邻苯二酚氧化酶、愈创木酚氧化酶和漆酶的活性变化规律。结果表明,在整个培养期内,7种酶均有活性,但活性差异较大,产酶高峰也不尽相同。     

黑木耳栽培过程中胞外酶活性变化

以5个黑木耳(Auricularia auricula)栽培菌株为实验材料,研究了黑木耳栽培过程中4种胞外酶活性的变化.结果表明,不同菌株胞外酶活性不同,但在整个生长发育过程中变化规律基本一致:即随着黑木耳子实体的生长发育,羧甲基纤维素酶(CMCase)和滤纸纤维素酶(FPase)的活性逐渐增强,并在子实体成熟时最高,子实体采收后活性迅速下降;漆酶(LAC)、多酚氧化酶(POD)活性在菌丝生长阶段较高,随着子实体的生长发育酶活下降.     

侧耳792几种胞外酶活性的测定比较

侧耳(792)在PDY液体培养基中培养时,淀粉酶、羧甲基纤维素酶、半纤维素酶、邻苯二酚氧化酶、愈创木酚氧化酶和漆酶的酶活有较大变化,产酶高峰期也不同；蛋白质含量和菌丝体重量在第10d达最大值,可作为菌丝体(菌种)收获期。     

甘蔗渣培养基栽培木耳过程中主要组分的降解和有关酶活的变化

实验以甘蔗渣加少量麦麸栽培毛木耳和光木耳,在栽培的不同阶段分析测定培养物的的主要化学组成成分和有关酶活性的变化。结果表明,两种木耳利用栽培底物的能力有明显差别;在栽培后期,毛木耳和光木耳分别消耗纤维素为74%和43%,半纤维素为78%和61%,木质素寿60%和35%。不过它们对这些底物的消耗又具有相似的阶段性变化的特点,即在子实体形成期的消耗速率都比菌丝生长期快。培养物的纤维素酶和半纤维素酶的活性也有阶段性变化特点。底物降解速率的变化与酶活水平的变化之间有一定对应关系,其中尤以毛木耳较明显。实验还分析培养物的过氧化物酶和多酚氧化酶的活性变化,简要地讨论了它们在栽培底物降解中的作用。     

香菇液体培养的基本生理研究

供试的三个菌株７４０２，ｘ１６和大光在相同的有机培养基中，其商体量不同，以７４０２生长最多；其漆酶和多酚氧化酶活性也有差异，以Ｘ１６产生的最高。在有机基础培养基中加花生仁纷或葵籽仁粉可以促进菌体生长量，而加草纸浆却提高了木聚糖酶活性。以加漩甲基纤维素的综合培养基为种液，接种到有草纸浆加花生仁粉的培养基中，可以诱导出较高的纤维素酶活性，但漆酶和多酚氧化酶浩性不高。反之，用玉术粉为种液时，仅出刃了高的漆酶和多酚氧化酶活性，而纤维素酶性却是低的。     

黄背木耳液体培养中几种相关酶活性的测定

采用液体培养法,对黄背木耳纤维素酶、淀粉酶、氧化酶等几种相关酶的活性变化规律进行了研究,结果表明:淀粉酶活性高峰出现最早(第6天),酶活性最高;纤维素酶的活性高峰随后出现(第8天);邻苯二酚氧化酶的活性高峰期到来更晚(第11天)。     

八个杏鲍菇菌株胞外酶活性及蛋白质含量的研究比较

对于8个杏鲍菇菌株发酵液中的羧甲基纤维素酶、半纤维素酶、漆酶、多酚氧化酶、淀粉酶的活性及其蛋白质含量进行了研究。测定结果表明:菌株CC的羧甲基纤维素酶、半纤维素酶、漆酶、淀粉酶活力均高于其它7个菌株,多酚氧化酶活性低于AA,PLA,PL7,PL174个菌株,高于PL3,PL6,PL16三个菌株;各菌株的蛋白质含量有着很大的差异,其中菌株CC的蛋白质含量为最高,并且蛋白质含量在一定程度上可以反应总酶活;分析表明:CC是一优良的杏鲍菇菌株。     

香魏蘑液体培养酶活性变化特点及固体培养抗菌性能的测定

采用液体培养法,对香魏蘑纤维素酶、淀粉酶、氧化酶等几种相关酶的活性变化规律进行了研究。结果表明:淀粉酶活性高峰出现最早(第5天),酶活性最高;纤维素酶的活性高峰随后出现(第7天);邻苯二酚氧化酶的活性高峰期到来更晚(第10天);同时采用固体培养法测定了香魏蘑和几种常见霉菌的作用,表明香魏蘑具有一定的抗耐特性。     

Changes in monoamine oxidase activity during thrombotic cerebral ischemia and protection mechanisms of ginkgolide B in tree shrews

AIM:The present study was designed to examine changes in monoamine oxidase (MAO) activity during cerebral ischemia and whether ginkgolide B's brain protection challenges with inhibiting monoamine oxidase. METHODS: The focal thrombotic cerebral ischemia was formed by photochemistry-induced in tree shews.MAO activities in different areas which include ischemic,core, penumbra and contralater and serum, were tested by enzyme color-compared way. The protein contents in different area above was examined by amino acid autoanalytic apparatus. RESULTS:MAO activities in ischemic core in different group were much lower than that in the sham operation group and contralatetral areas, with its peak at seventy-two hours after occlusion, but that in penumbra and serum ascended. There were significant differences in MAO activities between ischemic group and control (P＜0.01). In ginkgolide B(GB) group, the MAO activities in all areas but not in core descended, significant differences(P＜0.01) between in GB group and in twenty-four hours after occlusion. Changes in MAO activity was consistent with alterations of brain proein content(r=0.81,P＜0.05). CONCLUSION:The changes in monoamine neurotransmitters in core and penumbra considerably depend on the alterations of MAO activities after thrombotically cerebral ischemia. Probably, protective effects of GB on ischemic neurons is related to its acting as antagonist of platelet activating factor and regulator of monoamine oxidase.     

一氧化氮对瓶插月季呼吸作用及相关酶活性的影响

 以硝普钠( SNP) 为一氧化氮供体, 研究了NO及其清除剂PTIO (2-phenyl-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide) 处理对切花月季瓶插过程中生理变化及呼吸作用相关酶活性变化的影响。结果表明: 0.1 mmol·L^-1 SNP释放的NO可以降低月季切花的萎蔫率, 延长瓶插寿命, 增加花枝鲜样质量, 抑制COX (细胞色素氧化酶) 、AO (抗坏血酸氧化酶) 、PPO (多酚氧化酶) 活性, 抑制月季呼吸强度和乙烯释放, 延缓二者跃变高峰的出现, 延缓MDA含量和膜相对透性的升高, PTIO的处理提高了上述SNP处理下COX、AO、PPO的活性, 提高了呼吸速率, 促进MDA含量和膜相对透性的上升, 但抑制了乙烯的释放, 初步说明NO可能参与衰老过程中呼吸作用的末端氧化酶的活性调节。     

不同品种菊芋总酚含量、PPO活性、POD活性及其与褐变的关系

对5个菊芋品种的总酚含量、PPO活性、POD活性与褐变强度进行了测定。结果表明：不同菊芋品种的总酚含量、PPO活性、POD活性与褐变强度差异显著,其中3个北方品种的各项指标均高于2个南方品种。相关性分析显示,4个外形呈不规则瘤形品种的PPO活性与褐变强度之间呈显著正相关,相关系数r=0.982。褐变主成分分析表明：PPO活性、POD活性和总酚含量这3个变量共同影响菊芋的褐变。     

柑橘衰退病毒侵染对寄主植物同工酶及酸性病程相关蛋白表达的影响

以柑橘衰退病毒(Citrus tristeza virus,CTV)不同致病力株系接种寄主植物,比较分析了寄主植物体内过氧化物酶(peroxidase,POD)和多酚氧化酶(polyphenol oxidase,PPO)活性变化特点。结果表明,该病毒侵染对这2种酶活性的影响因寄主品种和CTV株系而异,CTV强毒和弱毒株系侵染均导致墨西哥莱檬植株中POD活性明显降低;在甜橙上,CTV强毒株系接种植株中POD活性则显著性提高,而弱毒株系接种对POD的活性无明显影响;在对该病毒具有较高抗性的枳壳中,接种CTV不同株系对POD活性均无明显影响。而在接种强毒株系N25的墨西哥莱檬中PPO活性有所增强,在枳壳上则表现为接种植株的PPO活性降低,在甜橙上PPO活性无明显的变化。POD、PPO和酯酶(esterase,EST)同工酶酶谱分析的结果显示,CTV弱毒株系接种枳壳后诱导产生了2条新的EST同工酶谱带,而在其他CTV接种植株上均未诱导表达新的POD、PPO及EST酶谱。酸性病程相关蛋白分析结果显示,CTV强毒株系在甜橙上诱导产生有6条明显的酸性病程相关蛋白条带。     

低氧胁迫下黄瓜幼苗根系多胺代谢的变化

 利用外源Spd、PAO 抑制剂研究了黄瓜幼苗根系在低氧水培时的生长状况以及内源PAs、H₂O₂ 含量和PAO活性的动态变化。结果表明, 外源PAs对低氧胁迫下黄瓜幼苗根系的生长有促进作用;低氧处理后3种PAs含量都明显上升, 外源Spd和PAO抑制剂增加了根系中的PAs含量, 降低了根系中H₂O₂ 含量, 减缓了低氧伤害; PAs为低氧胁迫的应激产物, PAO为适应酶类, 其活性随PAs含量的变化而发生变化。     

Methyl jasmonate plays a role in fruit ripening of ‘Pajaro’ strawberry through stimulation of ethylene biosynthesis

The role of methyl jasmonate (MJ) in strawberry (Fragaria × ananassa Duch. cv Pajaro) fruit ripening was investigated by monitoring its endogenous concentrations in fruit at various stages of development and the effects of exogenously applied MJ at these stages on ethylene biosynthesis. The concentration of endogenous trans-MJ was significantly higher in the white fruit (31.7–162.2 ng g⁻¹) and decreased sharply in half and fully ripe fruit. Higher concentrations of endogenous trans-MJ at the white stage of strawberry fruit development followed by a decline during fruit ripening indicate that MJ may play an important role in modulating fruit ripening. Significantly increased ethylene production was measured in the fruit when MJ was applied at white, half ripe and at fully ripe stage. The application of MJ (50 μM) resulted in significantly highest ethylene production and increased activities of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ACC oxidase as compared to all other treatments. The effect of exogenously applied MJ on ethylene production, ACC synthase and ACC oxidase activities was dependent on concentration of MJ applied and on fruit developmental stage. In conclusion, MJ in strawberry modulates fruit ripening, as its concentration is higher in white fruit and is declined with the progression of ripening and exogenous application of MJ increases ethylene production, activities of ACC oxidase and ACC synthase depending upon the concentration of MJ applied and fruit developmental stage.     

浸水处理对采后香菇褐变和质地的影响

以新鲜香菇为试验材料,通过测定香菇浸水后的质量、颜色、水分存在状态,以及多酚氧化酶活性和微观结构等指标,探索了浸水处理对采后香菇褐变和质地的影响。结果表明,浸水处理显著降低了香菇表面亮度,增加了总色差,浸水处理0～10 min内,香菇质量增加呈现先慢后快再变慢的趋势,不同部位香菇以外层菌皮吸水能力最强;浸水处理导致香菇T22弛豫时间延长,半结合水显著增加。然而,浸水处理降低了多酚氧化酶的活性和总酚含量,扫描电镜观察显示,浸水后香菇表面菌丝孔隙较少。因此,水分引起的采后香菇褐变不是多酚氧化酶酶促褐变的结果,而是水分导致了香菇表面结构的变化。     

西瓜交替氧化酶AOX2基因的克隆与分析

为了研究西瓜交替氧化酶基因家族在西瓜植株中可能发挥的功能,以西瓜（Citrullus lanatus）耐冷种质IVSM9为材料,根据植物不同物种交替氧化酶基因核苷酸保守区序列设计兼并引物,得到西瓜交替氧化酶（alterna-tive oxidase）AOX基因的中间片段。在已知序列的基础上,分别设计5’和3’末端扩增的...     

四种植物提取物对抵御葡萄霜霉病菌的影响

以对霜霉病具有抗性的葡萄品种‘左优红’和‘Fredonia’、委陵菜、无花果为试材,制备丙酮和2种乙醇提取物,研究4种植物的不同提取物在感病葡萄品种‘霞多丽’抵御霜霉病侵染中的作用,观测其对‘霞多丽’葡萄叶片多酚氧化酶(PPO)和β-1,3葡聚糖酶(Glu)活性的影响。结果表明:4种植物的提取物100倍稀释液均可在一定程度上降低葡萄霜霉病菌对‘霞多丽’叶片的侵染率,提取物作用效果强弱依次为70%乙醇委陵菜叶片提取物(60℃提取3h)50%丙酮的‘Fre-donia’叶片提取物70%乙醇的‘左优红’的提取物(50℃水浴提取5h),而无花果提取物作用最差;有效提取物均能不同程度地提高‘霞多丽’葡萄叶片的PPO和Glu活性。     

In vitro anti-platelet aggregative effect of procyanidins isolated from grape seeds

AIM: To study the possible anti-platelet aggregative mechanisms of procyanidins (PC) isolated from grape seeds in vitro. METHODS: Platelet-rich plasma (PRP) and platelet-poor plasma (PPP) were prepared from the blood of healthy volunteers. PC,diphenylene iodonium(DPI,a nonspecific NADPH oxidase inhibitor) and apocynin (a specific NADPH oxidase inhibitor) were used to observe the effects on collagen-induced platelet maximum aggregation rate using platelet aggregometer. The influences of PC on platelet NADPH oxidase activity, NO content and superoxide anion (O₂^-·) level were evaluated by chemiluminescence spectrometer. The role of PC in the expression of activated platelet markers (PAC-1 and CD62P) was observed by flow cytometry. RESULTS: PC (100 μmol/L), apocynin (10 μmol/L) and DPI (100 μmol/L) significantly inhibited collagen-induced maximum platelet aggregation rate (P<0.01). In collagen-activated platelets, NO content reduced and O₂^-· level increased,both of which were recovered by PC at concentration of 100 μmol/L (P<0.05). PC also obviously inhibited NADPH oxidase activity (P<0.01), and significantly down-regulated PAC-1 and CD62P expression (P< 0.05) in platelets. CONCLUSION: Procyanidins isolated from grape seeds have the anti-platelet aggregation function through inhibiting NADPH oxidase activity, further influencing platelet NO and O₂^-· levels.