6种植物提取物对荔枝霜疫霉的抑制作用

采用菌丝生长速率法测定了双氢青蒿素、厚朴酚、辣椒碱、青蒿琥酯、蛇床子素以及蒿甲醚6种植物提取物对32个采自广东,福建以及海南的荔枝霜疫霉菌菌株的抑制作用,以期为后期植物源农药的开发提供基础。结果显示,6种植物提取物对供试的32个菌株均有一定的抑制作用,以厚朴酚的抑制作用最好,双氢青蒿素次之,其它4种植物提取物的抑制作用相对较差,但均未出现不抑制现象。6种植物提取物对荔枝霜疫霉菌均有用于开发防治荔枝霜疫霉的植物源农药的潜力,以厚朴酚最佳。     

抗灰葡萄孢霉菌乳酸菌的筛选

从80株乳酸菌中筛选出45株具有抗灰葡萄孢霉菌活性的乳酸菌菌株,其中10株具有较强抗灰葡萄孢霉菌活性。对这10株乳酸菌菌株的抗植物致病真菌谱进行了研究,这10株乳酸菌对番茄早疫病菌,甜瓜疫霉菌,甜瓜枯萎病菌,苹果炭疽病菌的生长均有较强的抑制作用。其中1株具有广谱抗植物致病真菌活性的乳酸菌菌株BX6-4为植物乳杆菌。经番茄离体叶片接种试验发现,植物乳杆菌BX6-4的发酵液能够在体外强烈地抑制灰葡萄孢霉菌的生长。     

稀土甘氨酸配合物对微生物作用初探

本文用7种稀土甘氨酸配合物在实验室对微生物的作用进行了试验。通过杯碟法测定抑菌圈,用活菌平板计数法进行菌落计数,其结果是这7种稀土甘氨酸配合物对细菌均表现出抑制作用,对霉菌不起抑制作用。     

11种食药同源植物提取物对果蔬常见腐败菌的抑菌活性研究

本文以花椒、高良姜等11种食药同源植物提取物为供试材料,分别研究了其对扩展青霉、灰葡萄孢、链格孢和大肠杆菌、金黄色葡萄球菌等5种常见果蔬腐败菌的抑制作用。结果表明,花椒对三种霉菌抑制作用最强,高良姜和莱菔子对扩展青霉和链格孢有一定抑制作用。花椒对三种霉菌的最小抑菌浓度分别为25. 00、25. 00、50. 00 mg/m L,最小杀菌浓度分别为50. 00、100. 00、100. 00 mg/m L。花椒对三种霉菌的孢子萌发有显著抑制作用。花椒提取液处理樱桃番茄可显著降低果实发病率,延长果实保鲜期。11种食药同源植物提取液对大肠杆菌抑菌效果较差。高良姜和天麻对金黄色葡萄球菌抑菌效果突出,可显著抑制金黄色葡萄球菌生长,二者对金黄色葡萄球菌的MIC分别为7. 50和30. 00 mg/m L,MBC分别为15. 00和60. 00 mg/m L。     

化学药物防治霉菌及对香菇菌丝生长的影响试验初报

采用化学药物防治食用菌栽培中的各种不同病虫害 ,较为有效 ,但同时也给食用菌的菌丝生长带来不利的影响。对几种化学药物杀菌剂对霉菌及香菇菌丝生长的影响进行了研究。试验结果表明 ,5种杀菌剂的不同浓度水溶液对所试 4种不同霉菌的抑制作用亦不同 ,正常的使用浓度对香菇菌丝的生长速度多为减慢 ,并且有明显的抑制作用。     

分离引起柑橘腐烂、霉变的微生物及生物防治

从自然腐烂的柑橘中提取腐败菌,并对其进行分离,研究引起柑橘腐烂、霉变的主要微生物。通过菌落颜色、表面特征和质地等菌体形态的观察,获得初步鉴定的结果:细菌2种(编号A1、A2),分别为葡糖杆菌属和不动杆菌属;霉菌2种(编号B1、B2),分别为青霉菌属和毛霉属;酵母菌1种(编号C),为酵母属的酿酒酵母。用地衣芽孢杆菌SH003试验菌株考察对上述腐败菌的抑制作用,结果表明:地衣芽孢杆菌SH003发酵液对细菌和霉菌具有很好的抑制作用,但是对酵母菌的抑制作用不明显。     

农用抗菌素1222的研究

农用抗菌素1222是从我国土壤中分离得到一株链霉菌NO.1222所产生的抗菌素,对多种植物病原真菌、酵母及真菌有抑制作用,但对细菌无作用。链霉菌NO.1222经分类鉴定证明为烬灰链霉菌类群。农抗1222经理化性质的研究表明是属于四烯类抗菌素。我们把它用于浸种试验,表明对棉花枯萎病菌的灭菌有较好的效果。本文报告链霉菌NO.1222的菌种鉴定,抗菌素的理化性质及防治病害的研究结果。     

山东半岛农药污染点源放线菌多样性及抑菌活性

【目的】探究山东半岛农药污染点源放线菌多样性及非链霉菌抑菌活性,试图发现新放线菌和新抗生素。【方法】通过16S rDNA序列对已分离得到的154株纯培养放线菌进行初步分类鉴定并进行系统发育分析;采用管碟法和菌丝生长速率法检测10株非链霉菌的抑菌活性。【结果】154株放线菌覆盖7个科,8个属,有一株非链霉菌(205)可能为潜在的新种。10株非链霉菌的发酵液均对供试的植物病原真菌和细菌有不同程度的抑制作用,尤其是菌株Microbacterium oxydans JN853773和Kocuria rosea JN192402对所有供试病原菌都有强烈的抑制作用。【结论】农药污染点源可以作为开发新型抗生素产生菌的重要来源。     

链霉菌6803菌株对植物的化感作用

链霉菌属是绝大多数已知抗生素和一些重要活性物质的产生菌,它对高等植物是否具有化感作用尚缺乏研究. 从土壤中分离获得7个放线菌菌株,研究其对植物幼苗生长的抑制作用.结果表明： 链霉菌6803菌株在固体和液体发酵培养时均强烈抑制油菜根和稗草根的生长, 其液体发酵液的5倍稀释液对油菜和稗草苗生长的抑制分别达到60.7%和61.3%. 常规形态与生理生化试验表明,该菌株属于链霉菌属金色类群; 16S rRNA基因序列分析表明,该菌株为沙场链霉菌,基因序列相似性达到99.28%. 此菌株经过80～100 s紫外线照射筛选出的正突变菌株UV8024和UV100-2的10倍稀释发酵液对油菜幼苗生长的抑制作用比原始菌株分别提高了37.5%和38.1%, 经过1%硫酸二乙酯诱变50 min筛选出的正突变菌株D507的10倍稀释发酵液对油菜幼苗生长的抑制作用比原始菌株提高了29.8%. 链霉菌6803菌株对高等植物具有化感作用, 并可通过诱变育种提高其化感潜力.     

链霉菌6803菌株对植物的化感作用

链霉菌属是绝大多数已知抗生素和一些重要活性物质的产生菌,它对高等植物是否具有化感作用尚缺乏研究.从土壤中分离获得7个放线菌菌株,研究其对植物幼苗生长的抑制作用.结果表明:链霉菌6803菌株在固体和液体发酵培养时均强烈抑制油菜根和稗草根的生长,其液体发酵液的5倍稀释液对油菜和稗草苗生长的抑制分别达到60.7％和61.3％.常规形态与生理生化试验表明,该菌株属于链霉菌属金色类群;16S rRNA基因序列分析表明,该菌株为沙场链霉菌,基因序列相似性达到99.28％.此菌株经过80 ～ 100 s紫外线照射筛选出的正突变菌株UV8024和UV100-2的10倍稀释发酵液对油菜幼苗生长的抑制作用比原始菌株分别提高了37.5％和38.1％,经过1％硫酸二乙酯诱变50 min筛选出的正突变菌株D507的10倍稀释发酵液对油菜幼苗生长的抑制作用比原始菌株提高了29.8％.链霉菌6803菌株对高等植物具有化感作用,并可通过诱变育种提高其化感潜力.     

Inhibition of fungal growth and infection in maize grains by spice oils

Essential oils of 12 spices were tested for inhibitory activity against fungal infection and mycelial growth in post-harvest maize grains during storage. It was observed that the oils of cassia, clove (30 μl/g grain and above), star-anise (40 μl/g grain and above, geranium (30 μl/g grain and above) and basil (50 μl/g grain) inhibit the in viuo mycelial growth of established seed-borne infections of Aspergillus flavus, Curvularia pallescens and Chaetomium indicum as well as preventing infection following inoculation with A. flavus, A. glaucus, A. niger and A. sydowi . These oils also preserved the grain from natural A. flavus infection during the experimental period. Nutmeg, ginger and cumin oil (all at 50 μ1/g grain) could check mould growth and grain infection for only a brief period.     

Efficacy of Essential Oils on Fungi Isolated from Archaeological Objects in Saqqara Excavation,Egypt

The archeological objects constitute an important part of the worldwide cultural heritage. The impact of the fungal activity on the deterioration of cultural heritage is a global problem and their preservation over time is a challenging task. Antifungal activities of 12 essential oils (EOs) (black cumin, castor, cinnamon, clove, cumin, garlic, geranium, lavender, lemongrass, menthe, olive, and thyme) were examined against 16 fungal species isolated from three tested archaeological objects (wall painting stone, wooden statue, and pottery coffin) from Saqqara stores in Egypt. Molecular identification was carried out for the highly frequent species (Aspergillus niger, A. flavus and Rhizopus oryzae) in the three tested archaeological samples. Antifungal activity and minimal inhibitory concentration (MIC) of the tested EOs with different concentrations (0.125, 0.25, 0.5, 0.75, 1?μl/ml) were measured.

The most efficient EOs were thyme (MIC ranged from 0.25–0.75μl/ml) followed by clove (MIC ranged from 0.25–1?μl/ml) and geranium, (MIC ranged from 0.5–1?μl/ml). Thymol (37.1%) and p-Cymene (26.32%) were the active constituents of thyme, while Triacetin (69.36%) and eugenol (28.67) were the most efficient components of clove oil followed by geranium active components (à-Citronellol 20.62% and Geraniol 14.43%). Aspergillus niger was the most resistance species, while Fusarium oxysporum and Penicilium citrinium were the most susceptible ones.     

Effect of alcoholic extracts of wild plants on the inhibition of growth of Aspergillus flavus,Aspergillus niger,Penicillium chrysogenum,Penicillium expansum,Fusarium moniliforme and Fusarium poae moulds

Fungicidal activity of wild plants Larrea tridentata, Karwinskia humboldtiana, Ricinus communis, Eucalyptus globulus, Ambrosia ambrosioides, Nicotiana glauca, Ambrosia confertiflora, Datura discolor, Baccharis glutinosa, Proboscidea parviflora, Solanum rostratum, Jatropha cinerea, Salpianthus macrodonthus y Sarcostemma cynanchoides was evaluated against the moulds species Aspergillus flavus, Aspergillus niger, Penicillium chrysogenum, Penicillium expansum, Fusarium poae y Fusarium moniliforme moulds species. Alcoholic extracts 6% (w/v) were prepared using six grams of dried plant powders (leaves and stems) and alcohol (70% ethanol or 70% methanol). A spore suspension (1x10(6); ufc/ml) of each mould was prepared by adding saline solution (0.85%) and 0.1% tween 80. The extracts were mixed with Czapeck yeast agar (CYA) at 45-50 degrees C in 1:10 relation on Petri dishes. Triplicate Petri dishes of each treatment and for each mould were centrally inoculated and three Petri dishes were used without treatment as controls. The inoculated dishes and controls were incubated at 25 +/- 2 degrees C for eight days. The incubated dishes were examined each 48 h and after the colony diameter (radial growth) was measured. Two mould species were controlled by L. tridentata, B. glutinosa and P. parviflora. Extracts of L. tridentata in methanol or ethanol at 41.5-100% inhibited all six species of moulds.     

杉木、柳杉与黄连间作的初步研究

引言林农间作、林药间作等混农林业模式是提高农、林业生态系统功能和生产的有效途径。我国耕地面积小,森林资源不足,因此发展混农林业生产,最大限度地利用林地生产力,提     

HPLC法测定黄芩叶、花、种子中褪黑激素的含量

应用高效液相色谱—荧光检测系统测定了昼夜两个时间点黄芩鲜叶中褪黑激素的浓度差别,同时也检测了花、种子中褪黑激素的含量。结果表明,夜间和白天采集的新鲜叶片昼夜含量不同,分别为1.6503ng/g和0.5163ng/g。在花和种子中也检测到褪黑激素。尽管目前对褪黑激素在植物中的作用尚不完全清楚,但是有关植物中褪黑激素含量的研究将对营养、医药和农业等提供有益的信息。     

Effect of some mould inhibitors and herbal plants on mycotoxins production by Aspergillus flavus and Fusarium verticilloides in vitro and in stored corn grains

Clove oil, clove extract and butylated hydroxyanisole (BHA) completely suppressed the growth of both Fusarium verticilloides and Aspergillus flavus isolates. Black cumin and thyme extracts were more suppressive on F. verticilloides than A. flavus. Antitox-Plus (AP) had no effect on the growth of both the pathogens. The minimum inhibitory concentration (MIC) test revealed that A. flavus was more sensitive to Fix-A-Tox (FAT) and AP than F. verticilloides. In the growth media, all the tested substances, completely suppressed the production of aflatoxins by A. flavus and significantly reduced fumonisins production by F. verticilloides, particularly clove oil and extract. Treatment of immature grains with the tested mould inhibitors prior to inoculation with A. flavus and F. verticilloides significantly reduced mycotoxins production at the end of the storage period; moreover, highest reduction rates were realised by BHA and FAT. Complete or highly significant suppression of aflatoxins in mature grains were obtained by all the tested herbal and synthetic mould inhibitors. Ground clove buds contained the highest carvacrol content, whereas thymol content was higher in thyme extract. Clove oil was rich in eugenol. Alpha-tocopherol content was higher in ground black cumin (BC), followed by BC oil. Unsaturated fatty acid content was higher in thyme extract and ground BC than saturated fatty acids. Linolenic acid was the most predominant fatty acid in BC oil and extract, whereas behenic and arachidic acids were detected only in BC oil. Stearic acid was the main fatty acid in clove oil and extract, whereas oleic acid was the prevailing fatty acid in thyme extract.     

HPLC法测定黄芩叶、花、种子中褪黑激素的含量

应用高效液相色谱荧光检测系统测定了昼夜两个时间点黄芩鲜叶中褪黑激素的浓度 差别,同时也检测了花、种子中褪黑激素的含量。结果表明,夜间和白天采集的新鲜叶片昼夜含量不同,分别为1.6503 ng/g和0.5163 ng/g。在花和种子中也检测到褪黑激素。尽管目前对褪黑激素在植物中的作用尚不完全清楚,但是有关植物中褪黑激素含量的研究将对营养、医药和农业等提供有益的信息。     

Aflatoxin contamination of some common drug plants

This paper deals with the natural occurrence of aflatoxins in some common drug plants collected from storehouses in Bihar, India. Of 15 samples analyzed, 14 were aflatoxin positive. The highest level of aflatoxin contamination was detected in the seeds of Piper nigrum (1.20 micrograms/g), followed by the level detected in the seeds of Mucuna prurita (1.16 micrograms/g), and the lowest level was detected in the bark of Acacia catechu (0.09 micrograms/g). Of 158 isolates of Aspergillus flavus obtained from as many samples of drug plants, 49 were found to be toxigenic. The amount of aflatoxin B1 elaborated by the toxigenic isolates was in the range of 0.86 to 5.24 micrograms/ml of culture filtrate.     

Aflatoxin contamination of some common drug plants.

This paper deals with the natural occurrence of aflatoxins in some common drug plants collected from storehouses in Bihar, India. Of 15 samples analyzed, 14 were aflatoxin positive. The highest level of aflatoxin contamination was detected in the seeds of Piper nigrum (1.20 micrograms/g), followed by the level detected in the seeds of Mucuna prurita (1.16 micrograms/g), and the lowest level was detected in the bark of Acacia catechu (0.09 micrograms/g). Of 158 isolates of Aspergillus flavus obtained from as many samples of drug plants, 49 were found to be toxigenic. The amount of aflatoxin B1 elaborated by the toxigenic isolates was in the range of 0.86 to 5.24 micrograms/ml of culture filtrate.     

The effect of clove and cinnamon oils on growth of and aflatoxin production by Aspergillus flavus

The effect of different concentrations of clove and cinnamon oils was studied on the growth of and aflatoxin production by Aspergillus flavus in SMKY liquid medium. The effect of these compounds was also verified against aflatoxin production in maize. Significant reduction (P < 0.05) in the elaboration of aflatoxin in liquid culture after treatment with more than 100 μg ml^-1 of these compounds was recorded. Cinnamon oil exhibited maximum inhibitory action and reduced 78% aflatoxin formation on maize at 1000 mg kg^-1.