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1.
In a medium containing 40 g ethanol l–1, laccase production by Trametes versicolor was 2.6 unit per ml of the supernatant, which was over 20 times higher than that without ethanol. Laccase activity with ethanol was quite comparable to that with the well-known inducers such as veratryl alcohol, xylidine and guaiacol. With other white-rot fungi, Coriolus hirsutus and Grifola frondosa, ethanol had a similar stimulatory effect on laccase production.  相似文献   
2.
Oxygen consumption, air cell gases, hematology, blood gases and pH of Puna teal (Anas versicolor puna) embryos were measured at the altitude at which the eggs were laid (4150 m) in the Peruvian Andes. In contrast to the metabolic depression described by other studies on avian embryos incubated above 3700 m, O2 consumption of Puna teal embryos was higher than even that of some lowland avian embryos at equivalent body masses. Air cell O2 tensions dropped from about 80 toor in eggs with small embryos to about 45 toor in eggs containing a 14-g embryo; simultaneously air cell CO2 tension rose from virtually negligible amounts to around 26 torr. Arterial and venous O2 tensions (32–38 and 10–12 toor, respectively, in 12- to 14-g embryos) were lower than described previously in similarly-sized lowland wild avian embryos or chicken embryos incubated in shells with restricted gas exchange. The difference between air cell and arterial O2 tensions dropped significantly during incubation to a minimum of 11 torr, the lowest value recorded in any avian egg. Blood pH (mean 7.49) did not vary significantly during incubation. Hemoglobin concentration and hematocrits rose steadily throughout incubation to 11.5 g · 100 ml-1 and 39.9%, respectively, in 14-g embryos.Abbreviations PO2 partial pressure gradient of O2 - BM body mass - D diffusion coefficient - G gas conductance (cm3·s-1·torr-1) - conductance to water vapor - IP internal pipping of embryos - P ACO2 partial pressure of carbon dioxide in air cell - P AO2 partial pressure of oxygen in air cell - P aCO2 partial pressure of carbon dioxide in arterial blood - P aCO2 partial pressure of oxygen in arteries - P H barometric pressure (torr) - PCO2 partial pressure of carbon dioxide - P IO2 partial pressure in ambiant air - PO2 partial pressure of oxygen - P VCO2 venous carbon dioxide partial pressure - P VO2 mixed venous oxygen partial pressure - SE standard error - VO 2 oxygen consumption  相似文献   
3.
T. Suzuki 《Insectes Sociaux》1993,40(3):341-343
Summary The present study investigated the age at which insemination takes place in Polistes snelleni, a species in which mating begins while new reproductives are still emerging from the nest. Insemination of new reproductive females began as early as 5 days of age, and most females were inseminated by 10 days of age.  相似文献   
4.
The Dufour's gland of the paper wasp, Polistes fuscatus,is a source of the cues used by dominant females to recognize the eggs laid by subordinates or nonnestmates on pre (worker)-emergence nests. When dominant wasps were presented with an egg covered with either (1) the Dufour's gland extract of a subordinate cofoundress, (2) the extract of an egg from the same subordinate, or (3) the solvent alone, the dominant female destroyed and replaced the eggs covered with the Dufour's extract significantly more frequently than the other eggs. Eggs with the extract of a nonnestmate's Dufour's gland were also eaten significantly more frequently than those with the solvent. Given similar choices, subordinates did not destroy any eggs. The Dufour's gland appears to have little or no role in communicating dominance directly among aggressively interacting cofoundresses.  相似文献   
5.
漆酶高产菌株的筛选及产酶条件研究   总被引:17,自引:0,他引:17  
木质素是一种高度复杂的不定形的芳香族化合物 ,是仅次于纤维素的第二大再生有机资源 ,木质素的微生物降解及其有关酶类在制浆造纸工业和环境保护方面具有较大潜力。木质素的生物降解酶主要有木素过氧化物酶、漆酶、锰过氧化物酶和多酚氧化酶等。国外已有该方面的研究报道[5~ 7,9,10 ] ,但多集中在黄孢原毛平革菌 (Phanerochaetechrysosporium)木素过氧化物酶和锰过氧化物酶方面的研究 ;Slomczyn ski等[8] 研究了Botrytiscinerea的漆酶特性 ;国内有关研究报道较少[3 ,4 ] ,筛选漆酶高…  相似文献   
6.
通过化学、IR和UV光谱等方法发现云芝子实体的热水提取物 CVP 是由多糖、核酸和蛋白质等组成的混合物。通过柱层析方法从 CVP 中纯化出一个多糖组份 B-2-3,经完全水解证实组成它的单糖残基主要为Glc。用 HPLC 方法测得其分子量为 5.01×105。通过对甲基化及 1H 和 13C NMR 数据的分析发现 B-2-3 为一个以β-D-1, 4-Glc、β-D-1, 3-Glc 和β-D-1, 6-Glc 残基构成主链,同时在β-D-1, 3, 6-Glc 及β-D-1, 4, 6-Glc 处产生分枝的多糖。  相似文献   
7.
研究了彩绒草盖菌在不同碳源和氮源培养基中生长时,对纤维素酶、半纤维素酶、木质素酶(漆酶、多酚氧化酶、愈创木酚氧化酶)分泌的影响。结果表明不同碳源和氮源对酶类的分泌影响很大,富含淀粉的物质能明显促进木质素酶的分泌,而专一性底物(纤维素和半纤维素)对纤维素酶和半纤维素酶有诱导作用,麸皮也能诱导半纤维素酶的产生。  相似文献   
8.
The present study sought to evaluate the central nervous system (CNS) depressant, antioxidant, and cytotoxicity activity of methanol and aqueous extract of Trametes versicolor (METV and AETV). The CNS activity was assessed by the open field, hole-cross, forced swimming, thiopental sodium-induced sleeping time, hole-board, and rotarod tests in Swiss albino mice. For both extracts, a substantial decrease in locomotion was observed in open field and hole-cross tests. In addition, the molecular docking study has been implemented through Maestro V11.1. The higher dose of METV (400 mg/kg) and the lower dose of AETV (200 mg/kg) exhibited a significant decrease in immobility time in forced swimming test and increased prolongation of sleep in thiopental sodium-induced sleeping time test, respectively. In contrast, a moderate finding was observed for the hole-board and rotarod tests. Additionally, a significant DPPH scavenging assay and a high toxicity effect in brine shrimp lethality assay were observed. Besides, five phenolic compounds, namely baicalin, quercetin, catechin, p-hydroxybenzoic acid, and quinic acid, were used for the molecular docking study, whereas catechin demonstrated the highest binding affinity towards the targets. The findings conclude that the T. versicolor could be an alternative source for CNS anti-depressant and antioxidant activity.  相似文献   
9.
The insects known as thrips are commonly thought of as flower‐living and pestiferous organisms, but we report here a novel interaction between a phlaeothripine thrips species, Mirothrips arbiter gen. et sp. nov. and three species of social paper wasps in Brazil. This thrips species breeds inside the wasp colonies, and larval and adult thrips feed on wasp eggs, which become severely damaged. Infested nests can contain up to 300 M. arbiter gen. et sp. nov. individuals. The closest relatives of M. arbiter are two presumably predaceous species: Mirothrips bicolor sp. nov. , which inhabits abandoned Cecidomyiidae galls, and Mirothrips analis comb. nov. , described from individuals collected in the silken bags of the caterpillars of Psychidae moths. The behaviour exhibited by M. arbiter represents one of the most evolutionarily advanced lifestyles known among Thysanoptera, and we predict that other polistine species serve as hosts for this thrips in Brazil. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 332–341.  相似文献   
10.
We developed 10 polymorphic microsatellite loci for the Japanese paper wasp Polistes rothneyi using the magnetic particle method. Eight of the 10 loci tested were highly polymorphic, having four to eight alleles in P. rothneyi with an expected heterozygosity of 0.60–0.75. They also appeared to be applicable to other related species such as Polistes jokahamae. These loci can be used to study parameters concerning genetic relatedness such as worker reproduction and kin structure.  相似文献   
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