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141.
为了解青霉菌对植物吸收重金属元素铅的影响,把从土壤里分离到的具有铅富集能力的青霉菌(Penicillium Inordinate Arenicolasp.)接种到铅污染不同程度的土壤里,采用盆栽的方法观察这个菌株对毛桃(Prunuspersica L.Batsch)和大久保桃(Prunuspersica L.Batschcv.Okubao)铅胁迫的缓解效应。结果表明:(1)在接种青霉菌的土壤里生长的毛桃和大久保桃的根、茎、叶中铅累积量均比未接种青霉菌的低,茎叶中铅的分配率比未接种青霉菌的低;(2)接种青霉菌相对增加桃苗株高、叶绿素含量、硝酸还原酶及超氧化物歧化酶活性,降低叶片的细胞膜透性;随着土壤中铅胁迫强度的增加,接种青霉菌对增加桃树株高及改善叶片生理特性的效应递减;(3)两个桃树品种的上述生理性状受铅胁迫的影响及青霉菌的缓解效应存在品种间差异。  相似文献   
142.
碱性脂肪酶酶解鲐碎肉脂肪的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
采用扩展青霉(Penicillium expansum)PF868产生的碱性脂肪酶为酶源,酶解脱酯鲐碎肉,其最适条件为:32-34℃,pH9.3,酶活浓度40u/ml,碎肉的质量与酶液体积比为1g:5ml,脱脂时间50min。鲐碎肉的干基残脂率低于4.0%。  相似文献   
143.
毕璋友  吴惠君 《安徽农业科学》2014,42(4):1002-1003,1005
[目的]研究韭菜乙醇粗提物对储藏期柑橘青霉病菌的抑菌作用。[方法]采用粗提物浓度梯度的平板培养法培养柑橘青霉菌,判断不同溶剂和不同处理的粗提物对柑橘青霉菌是否有抑制作用。[结果]以酒精、丙酮和无菌水为溶剂的新鲜韭菜提取物对柑橘青霉菌都有不同程度的抑制作用,且随着浓度的增大抑菌作用增强,随着培养时间的延长抑菌作用降低;以无菌水为溶剂的药液抑制作用最大,24h时EC-50为431.385μg/ml。以无菌水为溶剂时,不同处理方法所得的韭菜乙醇粗提取物对柑橘青霉菌菌丝生长有明显的抑制作用,以新鲜茎叶对菌丝生长的抑制作用最大,干根次之,以干茎叶的抑制作用最小。[结论]韭菜乙醇粗提物对储藏期柑橘青霉病菌的菌丝有抑菌作用。  相似文献   
144.
本文收集了中国广西青霉属的46个种及其有性型名录,其中包括3个中国新记录。  相似文献   
145.
通过牛津杯法测定不同浓度膜醭毕赤酵母对扩展青霉体外抑制作用,将扩展青霉分别接入膜醭毕赤酵母和无菌水处理(对照组)的苹果,统计发病率和病变直径,结合顶空气相色谱-离子迁移谱(HS-GC-IMS)检测膜醭毕赤酵母拮抗组和对照组苹果的挥发性物质。结果表明,酵母在108 CFU/mL时抑菌圈最大(25.4 mm),并能显著抑制扩展青霉的孢子萌发率和芽管长度。培养10 d,酵母拮抗组的苹果发病率为10.6%,显著低于对照组(92.2%)。HS-GC-IMS共定性出38种挥发性成分,主要为酯类及醇醛化合物。对照组中丙酸乙酯、苯乙烯等含量显著高于酵母拮抗组。108 CFU/mL 膜醭毕赤酵母细胞悬浮液能够明显抑制扩展青霉和有效防治苹果采后青霉病。  相似文献   
146.
温度和干旱胁迫下绳状青霉菌P1的溶磷能力研究   总被引:1,自引:0,他引:1  
【目的】探究绳状青霉菌(Penicillium funicuiosum)P1对绿豆种子萌发的作用及其在温度和干旱胁迫下的溶磷能力,为生物磷肥的研制提供菌种资源和理论依据。【方法】将绿豆种子消毒后,用沾蘸法沾绳状青霉菌P1菌悬液,置于铺有2层湿滤纸的无菌培养皿中28 ℃培养4 d,以沾无菌水的处理为对照,测定绿豆种子的发芽率、发芽势、鲜质量、干质量、芽长、根长、发芽指数和活力指数,分析P1对绿豆种子萌发的影响。测定不同干旱程度(极轻度、轻度、中度、重度)和不同温度(5,10,12,15,20,25,28,35和40 ℃)条件下P1的溶磷能力,分析环境胁迫对P1解磷能力的影响。【结果】绳状青霉P1对绿豆种子萌发具有良好的促生效果,与对照相比,绳状青霉P1使绿豆幼苗的芽长和根长分别增长了149.14%和50.21%,发芽率提高了86.67%,种子活力提升了237.25%。绳状青霉P1在干旱胁迫下仍具有很强的溶磷能力,在重度干旱胁迫下的溶磷量可达418.85 mg/L。P1在10~35 ℃的条件下均能生长且具备溶磷能力,10 ℃条件下的溶磷量为34.67 mg/L,28 ℃条件下的溶磷量为1 120.52 mg/L,35 ℃条件下的溶磷量为364.97 mg/L。【结论】绳状青霉菌P1是一株对环境适应性较好且能促进植物生长的菌株,可用于制备微生物菌肥。  相似文献   
147.
Two new secondary metabolites, namely, pinodiketopiperazine A (1) and 6,7-dihydroxy-3-methoxy-3-methylphthalide (2), along with alternariol 2,4-dimethyl ether (3) and l-5-oxoproline methyl ester (4), which were isolated from a natural source for the first time but have been previously synthesized, were characterized from the marine sediment-derived fungus Penicillium pinophilum SD-272. In addition, six known metabolites (5–10) were also identified. Their structures were elucidated by analysis of the NMR and mass spectroscopic data. The absolute configuration of compound 1 was determined by experimental and calculated ECD spectra. Compound 2 displayed potent brine shrimp (Artemia salina) lethality with LD50 11.2 μM.  相似文献   
148.
Ten new (1–10) and 26 known (11–36) compounds were isolated from Penicillium griseofulvum MCCC 3A00225, a deep sea-derived fungus. The structures of the new compounds were determined by detailed analysis of the NMR and HRESIMS spectroscopic data. The absolute configurations were established by X-ray crystallography, Marfey’s method, and the ICD method. All isolates were tested for in vitro anti-food allergic bioactivities in immunoglobulin (Ig) E-mediated rat basophilic leukemia (RBL)-2H3 cells. Compound 13 significantly decreased the degranulation release with an IC50 value of 60.3 μM, compared to that of 91.6 μM of the positive control, loratadine.  相似文献   
149.
One new meroterpenoid-type alkaloid, oxalicine C (1), and two new erythritol derivatives, penicierythritols A (6) and B (7), together with four known meroterpenoids (2–5), were isolated from the marine algal-derived endophytic fungus Penicillium chrysogenum XNM-12. Their planar structures were determined by means of spectroscopic analyses, including UV, 1D and 2D NMR, and HRESIMS spectra. Their stereochemical configurations were established by comparing the experimental and calculated electronic circular dichroism (ECD) spectra for compound 1, as well as by comparison of the optical rotations with literature data for compounds 6 and 7. Notably, oxalicine C (1) represents the first example of an oxalicine alkaloid with a cleaved α-pyrone ring, whereas penicierythritols A (6) and B (7) are the first reported from the Penicillium species. The antimicrobial activities of compounds 1–7 were evaluated. Compounds 1 and 6 exhibited moderate antibacterial effects against the plant pathogen Ralstonia solanacearum with minimum inhibitory concentration (MIC) values of 8 and 4 μg/mL, respectively. Compound 6 also possesses moderate antifungal properties against the plant pathogen Alternaria alternata with a MIC value of 8 μg/mL.  相似文献   
150.
The effect of electrolyzed oxidizing (EO) water in combination with ozone to control postharvest decay of tangerine cv. “Sai Num Pung” was investigated. The spore suspension containing 105 conidia ml−1 of Penicillium digitatum was prepared. EO water was generated by electrolysis of various concentrations of NaCl solution (5, 25, 50% and saturated NaCl). The spore suspension was inoculated into EO water and incubated at 27 °C for 1, 2, 4, 8 and 32 min. It was found that the EO water with saturated NaCl completely inhibited the spore germination of the fungus within 1 min. When the fruits inoculated with P. digitatum were washed in EO water at the same concentrations as previous experiment for 4, 8 and 16 min and stored at 5 °C for 18 days, it was found that immersion of the fruit in EO water for 8 min was the most effective to reduce disease incidences. Moreover, washing fruit in EO water and kept in a refrigerated chamber at 5 °C with continuous ozone exposure at a concentration of 200 mg l−1 for 2 h day−1 to extend storage life suppressed the disease incidence until 28 days. However, none of the treatments had any effect on the quality of fruit such as total soluble solids, titratable acidity, percent weight loss and peel color. Therefore EO water may be useful for surface sanitation and ozone has potential to control the recontamination of postharvest diseases in tangerine fruit in storage room.  相似文献   
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