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141.
MD. Munir H. Khan S. Ali A. Fakhru'l-Razi MD. Z. Alam 《Journal of environmental science and health. Part. B》2013,48(4):381-386
Cellulase production was carried out by solid state bioconversion (SSB) method using rice straw, a lignocellulosic material and agricultural waste, as the substrate of three Trichoderma spp. and Phanerochaete chrysosporium in lab-scale experiments. The results were compared to select the best fungi among them for the production of cellulase. Phanerochaete chrysosporium was found to be the best among these species of fungi, which produced the highest cellulase enzyme of 1.43 IU/mL of filter paper activity (FPase) and 2.40 IU/mL of carboxymethylcellulose activity (CMCase). The “glucosamine” and “reducing sugar” parameters were observed to evaluate the growth and substrate utilization in the experiments. In the case of Phanerochaete Chrysosporium, the highest glucosamine concentration was 1.60 g/L and a high concentration of the release of reducing sugar was measured as 2.58 g/L obtained on the 4th day of fermentation. The pH values were also recorded. The range of the pH was about 5.15 to 5.56 in the case of Phanerochaete Chrysosporium. 相似文献
142.
Magdalena Gucia Grażyna Jarzyńska Anna K. Kojta Jerzy Falandysz 《Journal of environmental science and health. Part. B》2013,48(2):81-88
Mature specimens of Parasol Mushroom were collected annually in the outskirts of the Siemiany (2000–2003) and Rafa (2001–2003) sites in the northern part of Poland to examine temporal variations and similarities in the composition of 20 chemical elements. Analysis was done under the same condition and using well-validated analytical methods. Elements were determined by inductively coupled plasma–atomic emission spectroscopy and cold vapour–atomic absorption spectroscopy (Hg). The ranges of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn concentrations in the caps of fruiting bodies were similar (p > 0.05; Mann-Whitney U test) for both geographically distant sites, and these specimens from Rafa were more contaminated with Pb (p < 0.05; Mann-Whitney U test). The annual collections of caps in the Siemiany site varied in Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, Hg, Na, Rb and Sr and contents (0.05 < p < 0.001), while they were similar in Cr, K, Mg, Mn, Ni, P, Pb and Zn (p > 0.05; Mann-Whitney U test). The annual collections of specimens from the Rafa site varied in contents of Ag, Al, Ba, Ca, Fe, Hg, K, Mg, Mn, P, Rb and Zn (p > 0.05), while they were similar in Cd, Co, Cr, Cu, Na, Ni, Pb and Sr (p < 0.05). The results of this study imply that metallic elements content of Parasol Mushroom collected at the same undisrupted sites, and hence keeping the same geochemical condition for mushroom development and fructification (the same stands and probably the same mycelia), can fluctuate over the years or the life-span of mycelium. Hence, when assessing the nutritional value of essential metallic elements and status of non-essential or toxic metallic elements in Parasol's Mushroom caps (and probably also of other mushrooms species) to man, the possible fluctuation in contents over time have to be taken into account. 相似文献
143.
以从中国西南林区分离获得的外生菌根真菌彩色豆马勃(Pisolithus tinctorius 715,简称Pt715)、松乳菇(Lactarius delicious.ex Gray-1(简称Ld-1)、Lactarius delicious.exPink-2(简称Ld-2)、Lactarius delicious.ex White-3(简称Ld-3))为供试菌种,研究Hg、Cd对其吸收氮素的影响,从而筛选出在营养吸收上具有重金属耐受性的菌株。结果表明,重金属对外生菌根真菌吸收氮素营养的影响因重金属元素种类、真菌种类和氮素形态不同而异,Hg、Cd基本不会抑制供试菌种对有机态氮的吸收,而对NH+4-N、NO-3-N的吸收有不同程度的抑制或促进作用,但无明显的规律可循;Ld-1菌株具有一定的耐Hg性,在培养液中加入不同浓度的Hg后,Ld-1菌株对3种氮源的吸收均未受到明显抑制,相反在高Hg浓度下还促进了对NH+4-N、NO-3-N的吸收。Ld-1菌株有可能在Hg的胁迫下诱导合成了新的特异性蛋白,Hg与特异性蛋白结合从而缓解了其污染胁迫。 相似文献
144.
145.
Molecular diversity of arbuscular mycorrhizal fungi in relation to soil chemical properties and heavy metal contamination 总被引:1,自引:0,他引:1
Mehdi Zarei Stefan Hempel Tesfaye Wubet Gholamreza Savaghebi Mojtaba Khayam Nekouei 《Environmental pollution (Barking, Essex : 1987)》2010,158(8):2757-1576
Abundance and diversity of arbuscular mycorrhizal fungi (AMF) associated with dominant plant species were studied along a transect from highly lead (Pb) and zinc (Zn) polluted to non-polluted soil at the Anguran open pit mine in Iran. Using an established primer set for AMF in the internal transcribed spacer (ITS) region of rDNA, nine different AMF sequence types were distinguished after phylogenetic analyses, showing remarkable differences in their distribution patterns along the transect. With decreasing Pb and Zn concentration, the number of AMF sequence types increased, however one sequence type was only found in the highly contaminated area. Multivariate statistical analysis revealed that further factors than HM soil concentration affect the AMF community at contaminated sites. Specifically, the soils’ calcium carbonate equivalent and available P proved to be of importance, which illustrates that field studies on AMF distribution should also consider important environmental factors and their possible interactions. 相似文献
146.
147.
Marques AP Oliveira RS Rangel AO Castro PM 《Environmental pollution (Barking, Essex : 1987)》2008,151(3):608-620
Zn accumulation in Solanum nigrum grown in naturally contaminated soil in the presence of different types of organic amendments was assessed. Under the same conditions, the response of the plant to inoculation with two different isolates of arbuscular mycorrhizal fungi (AMF) (Glomus claroideum and Glomus intraradices) was also evaluated. S. nigrum grown in the non-amended soil always presented higher Zn accumulation in the tissues, with the addition of amendments inducing reductions of up to 80 and 40%, for manure and compost, respectively, and enhancing plant biomass yields. The establishment of S. nigrum in the Zn contaminated soil combined with the application of amendments led to a 70-80% reduction in the amount of Zn leached through the soil. The use of S. nigrum in combination with manure appeared as an effective method for reducing the effects of soil contamination, diminishing Zn transfer to other environmental compartments via percolation. 相似文献
148.
149.
We performed a quantitative assessment of the impact of impingement at power plants on the Hudson River white perch population We estimated that impingement reduces the abundance of each white perch year class by at least 10% and probably by 15–20% or more after 2–3 years of vulnerability to power plants We attempted to detect effects of impingement on average year-class abundance of white perch from a time series of abundance indices derived from impingement data We found, however, that neither impingement collection rates observed at Hudson River power plants nor beach seine data provide a reliable index of year-class strength in white perch. Even if a reliable index were developed, natural fluctuations in year-class strength are great enough that a short-term monitoring program would be inadequate for detecting even a large reduction in average year-class strength. We performed a multipopulation analysis using simple food chain and food web models The results suggest that any long-term decline in white perch abundance caused by impingement should be accompanied by an increase in the abundance of one or more competing fish species and by an increase in the biomass of adult white perch relative to young-of-the-year.We conclude that 1) at present, assessments of population-level impact of impingement should focus on short-term effects, 2) research is needed to develop a reliable index of year-class strength for use in long-term monitoring programs, 3) identification and quantification of natural environmental factors influencing year-class strength are needed to improve our ability to predict and detect changes in abundance, and 4) it would be useful in designing monitoring programs to focus on detecting patterns of change among populations and age groups rather than solely on declines in abundance of individual populationsResearch sponsored by the Office of Nuclear Regulatory Research, US Nuclear Regulatory Commission under Interagency Agreement No. 40-550-75 with the US Department of Energy under Contract W-7405-eng-26 with Union Carbide Corporation. Publication No. 2030, Environmental Sciences Division, ORNL. 相似文献
150.
The habitats, relative occurrence, and distribution of the white whale in the White Sea and the southeastern Barents sea in every month of the ice season have been studied using the results of an aerial ice survey along standard routes from 1970–1991. In these seas, white whales have been found in each month of the ice season, with single animals, groups, schools or gams, herds, and large congregations of several hundred animals accounting for 10, 22.8, 47.2, 12.9, and 7% of all aggregations of white whales observed, respectively. The relative occurrence of white whales in the White Sea is higher in March and May (32.5 and 30%, respectively) and lower in February, January, and November (15, 10, and 7.5%, respectively); in December and April, the whales are observed very seldom (2.5% in both months). In the southeastern Barents Sea, the relative occurrence of white whales is highest in May (53.3%) and considerably lower in December and February (16.7 and 10%); only a few animals are found during the remaining ice season. Regarding different habitats, the relative occurrences of white whales in open water, in water openings in the ice, near the edge of pack ice, and in ice packs with different degrees of closeness are 21.5, 11.4, 45.7, and 21.4%, respectively. 相似文献