10种南药植物提取物乙酰胆碱酯酶抑制活性的筛选模型研究

采用筛选模型对10种南药样品乙酸乙酯提取物的乙酰胆碱酯酶抑制活性进行了评价。结果表明:10种南药(益智、鸡血藤、决明子、巴戟天、溪黄草、金樱子、化橘红、佛手、绞股蓝、五指毛桃)均具有不同程度的乙酰胆碱酯酶抑制活性。当提取物浓度为1.0 mg/mL时,溪黄草、益智、化橘红、绞股蓝、五指毛桃表现出较强的抑制活性,平均抑制率大于50%,分别为89.59%,77.10%,67.54%,52.62%,52.29%,其他5种南药的平均抑制率在20.81%~49.81%之间;提取物浓度为0.1 mg/mL时,溪黄草、益智、佛手仍表现出相对较强的抑制活性,平均抑制率大于25%,其他7种南药的平均抑制率在6.07%~24.78%之间。应该深入研究复方中药治疗老年痴呆的药效物质基础,加大对南药资源的开发利用。     

四种植物提取物对马铃薯晚疫病菌的抑制作用

本试验测定了苦参(Sophora flavescensAit.)、瑞香狼毒(Stellera chamaejasma)、乌头(Aconitum carmichaeli Debx.)、甘草(Glycyrrhiza uralensis Fisch.)的乙醇和水提取物对马铃薯晚疫病菌的生物活性。结果表明:4种植物提取物对马铃薯晚疫病菌都具有明显的抑制作用,其中室内毒力最强的为苦参醇萃取物(ACS4),其次分别为瑞香狼毒水提取物(HCS1)、乌头醇萃取物(ACS3)和甘草醇萃取物(ACS2),其抑制中浓度分别为0.0177g·mL-1、0.0207g·mL-1、0.0305g·mL-1和0.0623g·mL-1;浓度为0.05g·mL-1的ACS4、0.08g·mL-1的HCS1、0.2g·mL-1的ACS2抑制产孢效果与空白对照间差异达极显著;经ACS4和HCS1处理的晚疫病菌侵染马铃薯后病情指数显著低于CK,说明这两种提取物能有效抑制晚疫病菌的侵染。ACS2、ACS3也有一定效果,但不显著。     

植物乙醇提取物对荔枝蒂蛀虫的防治研究

通过室内饲养观察和田间试验,研究不同药剂对荔枝蒂蛀虫的防治效果。通过室内饲养观察,从9种植物乙醇提取物中筛选出了飞机草茎叶乙醇提取物、非洲山毛豆乙醇提取物和大叶桉叶乙醇提取物3种对荔枝蒂蛀虫成虫具有较好的产卵忌避作用的植物乙醇提取物;田间药效试验结果表明,上述3种忌避作用物质处理5d后,对荔枝蒂蛀虫的产卵防治效果分别为82.02%,82.17%,74.37%,显著高于10%高效灭百可乳油(47.57%)和90%敌百虫结晶的防治效果(35.99%)。3种乙醇提取物对荔枝果实的保果效果分别为84.21%,85.26%,80.00%,对荔枝蒂蛀虫具有较好的防治和保果效果。      

中草药提取物对香蕉镰刀菌枯萎病病原菌的抑制作用

本研究测试了 123 种常见中草药提取物对香蕉镰刀菌枯萎病病原菌的抑菌作用。结果表明,供试提取物 100 倍稀释液对菌株 B1 的菌丝生长和孢子萌发的抑制作用在 50 %以上的分别有 15 种和 14 种;对菌株B2 的菌丝生长和孢子萌发抑制作用在 50 %以上的提取物分别有 7 种和 9 种。进一步测试发现,经过 200 倍 稀释,只有丁香提取物和厚朴提取物对菌株 B1 的菌丝生长和孢子萌发抑制作用均达到 50 %以上。丁香提取物对菌株 B1 和菌株 B2 菌丝生长的抑制中浓度分别为 3 396.31 μg/mL 和 3 375.87 μg/mL。     

20种植物提取物对芒果炭疽菌的抑制作用

研究了16科20种（其中12种为中草药）植物的丙酮提取物对芒果炭疽病菌株的抑制作用,初步分析了利用植物源农药解决芒果炭疽病抗药性问题的可能性.结果表明,同一药物在不同浓度下作用效果可能存在较大的差异.芒果炭疽病抗药性菌株对供试植物丙酮提取物没有明显的抗药性,100mg/mL（每mL含100mg干物质的提取物）浓度下石菖蒲、艾草、阳春砂、益智、飞机草等植物在芒果炭疽菌抗药性菌株室内试验中其作用效果明显优于1000 mg/L多菌灵,其中石菖蒲丙酮提取物对芒果炭疽病菌敏感菌株（ZJS）、抗药性菌株（ZJR）有效中浓度EC50分别为5.91,4.06 mg/mL,艾草丙酮提取物对芒果炭疽病菌敏感菌株（ZJS）、抗药性菌株（ZJR）有效中浓度EC50分别为9.24,14.53 mg/mL.     

20种植物提取物对南方根结线虫的毒杀活性

采用浸渍法测定13科20种植物乙醇提取物对南方根结线虫的毒杀活性。结果表明：酸豆、牛角瓜、番荔枝、苦楝乙醇提取物以10 mg/mL处理后24 h,供试2龄线虫校正死亡率分别为82.13%、85.71%、89.28%、89.28%,处理后48 h,校正死亡率分别为89.01%、96.34%、92.67%和96.34%,均具有强杀线虫活性;毒力测定结果表明：处理后24 h和48 h,4种提取物的LC50由小到大顺序为：酸豆＜牛角瓜＜番荔枝＜苦楝。     

几种植物乙醇提取物对螺旋粉虱的生物活性

采用玻管药膜法和田间试验研究飞机草、青葙、假蒟等6种植物叶片的乙醇提取物对螺旋粉虱的生物活性.结果表明,各供试提取物均对螺旋粉虱表现出一定的生物活性,其中以飞机草和青葙的活性最高,其LC50分别为753.40,999.81 mg/kg,其余4种提取物对螺旋粉虱的活性大小依次为:假茼>菠萝蜜>含羞草>桃金娘.田间试验结果表明,飞机草和青葙提取物对螺旋粉虱成虫均具有较高活性,在50倍浓度处理下,飞机草和青葙提取物的防效均在75%以上.     

茜草不同极性提取物的体外抑菌活性研究

本文采用k-b纸片法研究了茜草不同极性溶剂提取物的抑菌作用,结果表明,石油醚提取物浓度为50mg／ml时,抑菌率为25．03％;乙酸乙酯层提取物浓度为50mg／mL时抑制率最高,为48．64％;丙酮层提取物浓度为50mg／mL时抑制率最高,为61．59％;甲醇层提取物浓度为50mg／mL时抑制率最高,为46．09％。     

西湖龙井产区茶树炭疽菌分离鉴定及其植物源抑菌剂筛选

为筛选出对西湖龙井产区茶树炭疽病菌具有较好抑菌活性的植物提取物,对该地区的茶树炭疽病菌进行了分离鉴定,采用菌丝生长速率法测定了12种植物提取物的抑菌活性,进一步采用浓度梯度试验测定了3种抑菌活性较好的植物提取物的抑菌毒力。研究结果表明,引起西湖龙井产区茶树炭疽病的主要病原为山茶炭疽菌(Colletotrichum camelliae);在200 mg·L^-1时香荆芥酚、牛至精油和紫苏醛对该菌的抑菌活性较好,菌丝生长抑制率均在68%以上,有效中浓度(EC₅₀)分别为71.459、77.155、110.753 mg·L^-1。显微观察发现,在添加有效中浓度的香荆芥酚、牛至精油和紫苏醛的培养基上进行病原菌培养时,菌丝形态发生明显改变,呈现变形扭曲、皱缩干瘪等现象。综上所述,香荆芥酚、牛至精油和紫苏醛对山茶炭疽菌具有较强的抑菌活性,具有开发为植物源杀菌剂的应用潜力。     

茶叶不同提取物及不同茶叶对结核分枝杆菌抑制作用的研究

为探明茶叶对结核分枝杆菌H₃₇Ra菌株的抑制作用,采用牛津杯法对H₃₇Ra菌株进行抑菌试验,研究不同茶叶提取物(茶多酚、茶多糖和茶皂素)及不同种类茶叶(华农绿针、大宗炒青、广东大叶青、福鼎寿眉、铁观音、凤凰单丛、祁门红茶、下关沱茶、青砖茶)对H₃₇Ra菌株活性的抑制能力。结果显示,茶多酚对H₃₇Ra菌株表现出显著的抑菌能力,随着茶多酚浓度的增加,抑菌效果逐渐增强;在40 mg·m L^-1下,茶多酚显示出长期抑制H₃₇Ra菌株生长的能力;茶多糖和茶皂素对结核分枝杆菌没有抑制作用;不同种类茶叶表现出不同程度的抑菌能力,其中凤凰单丛的乙酸乙酯部较其他分离部有更强的抑菌能力,其60%乙醇洗脱的柱层析分离物抑菌能力最强,推测茶多酚是抑制H₃₇Ra菌株生长的主要成分。研究结果证实了茶叶对H₃₇Ra菌株具有抑制作用,且茶叶不同提取物和不同种类茶叶在抑菌能力上存在差异,为开发结核病相关的抗菌药物提供了一个新思路。     

12种热带植物粗提物对胡椒瘟病的抑菌活性测定

用生长速率法测试了12种热带植物乙醇粗提物对胡椒瘟病菌的离体抑菌活性。结果表明，当供试质量浓度为干样10 mg/mL时，鹰爪和马缨丹粗提物对胡椒瘟病菌菌丝生长的抑菌率均达到90%以上，分别为91.95%和94.32%。可见这两种植物粗提物对供试病原菌菌丝生长具有明显的抑制作用，值得进一步研究开发。     

茶鲜叶挥发物组分及对茶树病原菌的熏蒸抑制作用

为明确茶鲜叶中的挥发物组分及其与茶树主要病原菌之间的关系,利用HS-SPME-GC-MS法萃取分析茶鲜叶挥发物组分,并以茶褐枯病菌、茶云纹叶枯病菌、茶炭疽病菌、茶轮斑病菌为目标菌,测定茶鲜叶主要挥发物单体组分对病原菌的熏蒸抑制作用.结果显示,从茶鲜叶挥发物中分离到28个组分,鉴定出其中19个组分,占挥发物总量的94.4...     

山竹果皮提取物农药活性研究

探索山竹果皮提取物在农业中的杀虫抗菌活性,为新型植物源农药的开发提供理论依据。采用浸叶法测定山竹果皮乙醇、石油醚、氯仿、乙酸乙酯及正丁醇等5种提取物对斜纹夜蛾3龄幼虫拒食和毒杀活性;以生长速率法测定这5种提取物对12种植物病原真菌的抗菌活性。结果显示：山竹果皮提取物对斜纹夜蛾3龄幼虫均具有一定的拒食及毒杀作用,以氯仿提取物的拒食活性最高,其24和48 h拒食率分别为72.51%和65.75%;而毒杀作用以石油醚提取物最强,其处理5 d后,斜纹夜蛾的校正死亡率为53.70%。抑菌试验显示山竹氯仿提取物对芒果炭疽病菌、水稻纹枯病菌、番茄灰霉病菌和芒果蒂腐病菌等4种植物病原真菌具有明显抑制菌丝生长作用,其EC50值分别为0.230 5、0.429 3、0.265 2和 0.390 1 mg/mL。由此说明,山竹果皮提取物具有良好的杀虫抗菌活性,基于山竹产物开发新型植物源农药具有潜在的利用价值。     

圆滑番荔枝叶乙醇提取物不同萃取组分对胡椒瘟病菌的抑菌活性测定

采用液-液分配法对圆滑番荔枝叶乙醇提取物进行萃取分离,得到石油醚、三氯甲烷、乙酸乙酯等不同萃取组分。采用生长速率法测定不同萃取组分对胡椒瘟病菌的抑制作用。结果表明：乙酸乙酯萃取组分对胡椒瘟病菌的抑制作用最强,其中20 mg/mL乙酸乙酯萃取组分对胡椒瘟病菌菌丝生长的抑制率达到74.43%,具有较好的抑菌效果。     

Antifungal and Larvicidal Activities of Phlorotannins from Brown Seaweeds

Phlorotannins are secondary metabolites produced by brown seaweeds with antiviral, antibacterial, antifungal, and larvicidal activities. Phlorotannins’ structures are formed by dibenzodioxin, ether and phenyl, ether, or phenyl linkages. The polymerization of phlorotannins is used to classify and characterize. The structural diversity of phlorotannins grows as polymerization increases. They have been characterized extensively with respect to chemical properties and functionality. However, review papers of the biological activities of phlorotannins have focused on their antibacterial and antiviral effects, and reviews of their broad antifungal and larvicidal effects are lacking. Accordingly, evidence for the effectiveness of phlorotannins as antifungal and larvicidal agents is discussed in this review. Online databases (ScienceDirect, PubMed, MEDLINE, and Web of Science) were used to identify relevant articles. In total, 11 articles were retrieved after duplicates were removed and exclusion criteria were applied. Phlorotannins from brown seaweeds show antifungal activity against dermal and plant fungi, and larvicidal activity against mosquitos and marine invertebrate larvae. However, further studies of the biological activity of phlorotannins against fungal and parasitic infections in aquaculture fish, livestock, and companion animals are needed for systematic analyses of their effectiveness. The research described in this review emphasizes the potential applications of phlorotannins as pharmaceutical, functional food, pesticide, and antifouling agents.     

6种草本药用植物种子超低温保存技术研究

以草本药用植物杜若、过江藤、夏枯草、皱果苋、罗勒和山香的成熟种子为材料,探讨了含水量和冷冻方法对种子超低温保存的影响。结果表明,经液氮超低温冷冻后,6种草本药用植物种子发芽率较对照组均有显著差异(p0.05);适宜的含水量下,种子经过超低温冷冻后其发芽率甚至高于对照组。3种冷冻方法中,玻璃化冷冻法更适合过江藤和山香种子的超低温保存,缓慢冷冻法更适合皱果苋、杜若和夏枯草种子的超低温保存,直接冷冻法适合于杜若和罗勒种子的超低温保存。所以,液氮超低温冷冻法保存杜若等6种草本药用植物种子是可行的;含水量对超低温保存前后夏枯草、山香和罗勒种子的发芽率影响显著。     

解淀粉芽孢杆菌HAB-7对18株植物病原真菌的抑制作用

HAB-7是一株分离自豇豆根际土壤、具有较强抑菌作用的解淀粉芽孢杆菌(Bacillus amyloliquefaciens)。研究HAB-7对18株植物病原真菌及其发酵液粗提蛋白对植物病原的抑制作用,并测定其对番茄种子的促生作用。采用平板对峙法测定其对18株植物病原真菌的抑制活性,以橡胶树炭疽菌为指示菌,对其发酵上清液经60%、80%硫酸铵盐析获得的抗菌粗蛋白进行测试;并将HAB-7菌液稀释成6个浓度梯度,分别用来对番茄种子进行促生测试。结果显示：HAB-7对18株植物病原真菌的平均抑菌率为61.03%;     

Antifungal properties of Agapanthus africanus L. extracts against plant pathogens

Crude extracts of various Agapanthus africanus plant parts were screened in vitro against eight economically important plant pathogenic fungi. Radial mycelial growth was inhibited significantly (P<0.05) in five test organisms, while Pythium ultimum, and to a lesser extent Fusarium oxysporum and Alternaria alternata, showed a degree of tolerance. Subsequently, these crude extracts were tested in vivo in the greenhouse against Mycosphaerella pinodes, the cause of black spot or Ascochyta blight in peas. Fourth internode leaves were removed from 4-week-old pea plants, placed on moist filter paper in Petri dishes and inoculated with a M. pinodes spore suspension 30 min before and after treatment with the extracts. The control of Ascochyta blight by different concentrations of the crude extracts was measured in terms of lesion size over a 6-d period at 20 °C in a growth cabinet. All crude extracts significantly reduced lesion development caused by M. pinodes when leaves were inoculated with spores both before and after treatment with the extracts. Neither of the extracts showed any phytotoxic reaction on the leaves, even at the highest concentration applied. A combined aerial part crude extract of A. africanus was additionally evaluated against sorghum covered (Sporisorium sorghi) and loose (Sporisorium cruentum) kernel smuts under field conditions over two seasons. The extract and a standard fungicide, Thiram that served as a positive control, were applied as seed treatments 1 h after artificially inoculating separate sets of sorghum seed with smut spores. Inoculated, but untreated seeds served as a negative control. The extract reduced the incidence of both loose and covered kernel smuts significantly (P<0.05) and compared favourably with the prescribed fungicide, Thiram. Both treatments resulted in significant yield increases compared to the untreated control. From these results it was concluded that the aerial part crude extract of A. africanus possesses sufficient in vivo antifungal activity to warrant a further investigation.     

Aaptamine Derivatives with Antifungal and Anti-HIV-1 Activities from the South China Sea Sponge Aaptos aaptos

Five new alkaloids of aaptamine family, compounds (1–5) and three known derivatives (6–8), have been isolated from the South China Sea sponge Aaptos aaptos. The structures of all compounds were unambiguously elucidated by spectroscopic analyses, as well as by comparison with the literature data. Compounds 1–2 are characterized with triazapyrene lactam skeleton, whereas compounds 4–5 share an imidazole-fused aaptamine moiety. These compounds were evaluated in antifungal and anti-HIV-1 assays. Compounds 3, 7, and 8 showed antifungal activity against six fungi, with MIC values in the range of 4 to 64 μg/mL. Compounds 7–8 exhibited anti-HIV-1 activity, with inhibitory rates of 88.0% and 72.3%, respectively, at a concentration of 10 μM.