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941.
Rafał Ogórek Wojciech Pusz Paweł P. Zagożdżon Bartosz Kozak Henryk Bujak 《Geomicrobiology journal》2017,34(10):823-833
This paper is a speleomycological report from a former aluminous shale mine in Janowiec, Poland. Fungi were identified morphologically and molecularly. Microclimatic conditions differed significantly between locations of the study. However, the external environment around the mine did not directly increase the community composition and concentration of fungi in the mine. The density of fungi isolated from the air outside the mine was 63.1 colony forming units (CFU) per 1 cm3 of air. Inside the mine, fungal density ranged from 287.5 to 655 CFU per 1 m3 from the air, 28.4 to 131.1 CFU per 1 cm2 from the rock surfaces and 288.1 to 335.1 CFU per 1 cm3 from the water. Pearson correlation analysis showed that the levels of fungi isolated from the air were correlated positively with temperature, relative humidity and CO2 concentration. The concentration of fungi isolated from the rock surfaces showed a positive correlation with air flow. Five species of filamentous fungi were isolated from the sampled external air, 10 species from the internal air, six species from the rock surface and 11 species from the water. The fungi most frequently isolated from the air and water of the mine belonged to Penicillium spp., whereas from the rock surface, Geomyces pannorum was most frequently isolated. Some of the fungi present in the mine can be psychrotolerant and pathogenic for humans and animals, and they can also cause degradation of rocks. 相似文献
942.
《Animal : an international journal of animal bioscience》2017,11(11):2084-2093
There is a commitment by the European pig sector to ban surgical castration of male piglets in the European Union in 2018. One alternative to castration is to raise entire male pigs, with an increased risk of boar taint. A field study was performed to: (1) evaluate inter- and intra-farm variation in boar taint prevalence, (2) investigate factors measured at slaughter influencing boar taint and (3) evaluate the relationship between sensorial scoring by a trained panel and the concentration of boar taint components. From 34 farms, neck fat samples were collected from all entire male pigs in at least two slaughter batches per farm (78 batches; 9167 animals). In addition to olfactory boar taint analysis, data were also collected on fresh skin lesions (score 0 to 3) at the slaughter line, slaughter weight, lean meat percentage, duration of transport, time spent in lairage, total delivery duration, day length, shortening of days and outdoor mean temperature. Using the hot iron method, neck fat samples were scored (eight-point scale) for boar taint. Average boar taint prevalence (score ≥3) was 5.6±2.5% and the mean difference between the maximum and minimum prevalence per farm was 4.3±3.2%. Androstenone (AND), skatole (SKA) and indole concentrations were measured for a subset (n=254) of the samples. According to binomial univariate mixed models, entire male pigs with a higher skin lesion score had higher odds of having boar taint (P=0.031), as did fatter entire male pigs (P<0.001). In the binomial multivariate mixed model lean meat percentage (P<0.001) and outdoor mean temperature (P=0.005) remained as only significant factors. Based on our results, we can conclude that these statistically significant at least partially influence the prevalence of boar taint. According to the binomial univariate mixed models SKA concentration in liquid fat seems a better predictor for boar taint than AND. There were no significant synergetic effects between boar taint compounds. 相似文献
943.
以除虫菊(Pyrethrum cinerariifolium Trey.)无菌苗为外植体,研究除虫菊发状根的诱导、培养条件优化,并对发状根中的除虫菊素进行检测和生物活性测定。结果显示,乙酰丁香酮能促进除虫菊下胚轴和子叶发状根的诱导,当乙酰丁香酮浓度为150 μmol/L时除虫菊下胚轴和子叶的诱导率为对照的2.29倍和2.66倍,预培养6 d时,下胚轴发状根诱导率为对照的2.25倍,发根农杆菌A4的诱导率均高于ATCC15834,愈伤组织较适合发状根的诱导,愈伤组织侵染后适合在无激素的MS培养基上进行发状根诱导,250 mL三角瓶中添加50 mL MS培养基较适合发状根的生长。对除虫菊发状根进行PCR检测发现,发根农杆菌含有的Ri T-DNA的rolB基因已整合进入发状根基因组中。通过GCMS检测发现,愈伤组织中除虫菊素的6种成分均未检测到,而发状根中检测到瓜菊素Ⅰ、茉酮菊素Ⅰ和茉酮菊素Ⅱ 3种成分,发状根对粘虫的拒食作用明显优于愈伤组织。本研究为通过组织培养方式生产除虫菊素奠定了基础。 相似文献
944.
945.
弗赖森草螺菌RE3-3合成生长素及其促生作用的研究 总被引:1,自引:0,他引:1
研究弗赖森草螺菌RE3-3菌株的培养条件对其生长素(IAA)生物合成的影响,并观察菌株合成IAA对芦苇及香蒲幼苗的促生影响。在单因素筛选和菌液初始浓度确定的基础上,对菌株RE3-3合成IAA的培养条件进行优化;以IAA标准物质为对照,对菌株合成IAA促进芦苇及香蒲苗的生长能力进行分析。通过高效液相色谱与质谱分析鉴定其产物为IAA;培养基中含0.07%L-色氨酸及1%葡萄糖,在p H 7.0、温度30℃、培养时间48 h的最佳培养条件下,菌株RE3-3可产生最大量的IAA(74 mg/L);菌株合成IAA作用芦苇及香蒲苗时,其促生效果最显著,植株根长、茎长明显提高。通过改变菌株RE3-3的培养条件,可提高其合成IAA的能力,且菌株RE3-3合成IAA具有显著的促生效果。 相似文献
946.
Effects of developmental conditions on growth,stress and telomeres in black‐legged kittiwake chicks
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Rebecca C. Young Jorg Welcker Christopher P. Barger Scott A. Hatch Thomas Merkling Evgenia V. Kitaiskaia Mark F. Haussmann Alexander S. Kitaysky 《Molecular ecology》2017,26(13):3572-3584
Early‐life conditions can drive ageing patterns and life history strategies throughout the lifespan. Certain social, genetic and nutritional developmental conditions are more likely to produce high‐quality offspring: those with good likelihood of recruitment and productivity. Here, we call such conditions “favoured states” and explore their relationship with physiological variables during development in a long‐lived seabird, the black‐legged kittiwake (Rissa tridactyla). Two favoured states were experimentally generated by manipulation of food availability and brood size, while hatching order and sex were also explored as naturally generating favoured states. Thus, the favoured states we explored were high food availability, lower levels of sibling competition, hatching first and male sex. We tested the effects of favoured developmental conditions on growth, stress, telomere length (a molecular marker associated with lifespan) and nestling survival. Generation of favoured states through manipulation of both the nutritional and social environments furthered our understanding of their relative contributions to development and phenotype: increased food availability led to larger body size, reduced stress and higher antioxidant status, while lower sibling competition (social environment) led to lower telomere loss and longer telomere lengths in fledglings. Telomere length predicted nestling survival, and wing growth was also positively correlated with telomere length, supporting the idea that telomeres may indicate individual quality, mediated by favoured states. 相似文献
947.
948.
Guoqiang Chen Jiming Wang Yulong Su Youshuang Zhu Ge Zhang Hongwei Zhao 《Preparative biochemistry & biotechnology》2017,47(10):963-969
Pullulan with different molecular-weight could be applied in various fields. A UV-induced mutagenesis Aureobasidium pullulans UVMU6-1 was obtained from the strain A. pullulans CGMCC3.933 for the production of low-molecular-weight pullulan. First, the obtained polysaccharide from A. pullulans UVMU6-1 was purified and identified to be pullulan with thin-layer chromatography, Fourier transform infrared, and nuclear magnetic resonance. Then, culture medium and conditions for this strain were optimized by flask fermentation. Based on the optimized medium and culture conditions (pH 4, addition of 4?g/L Tween 80 for 96?hr of cultivation), continuously fermentation was performed. The highest pullulan production and dry biomass was 109 and 125?g/L after fermentation for 114?hr, respectively. The average productivity was about 1?g/L/hr, which was intensively higher than the previous reported. This study would lay foundations for the industrial production of pullulan. 相似文献
949.
950.