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101.
Nataliya Voloshchuk Mona Knop Thomas Colby Erich Kombrink Lothar Hennig Diana Hofmann Dieter Sicker Andrej Gryganski Margot Schulz 《Chemoecology》2007,17(1):1-12
Summary. Doratomyces stemonitis (Hyphomycetales, Dematiaceae) is a saprotrophic fungus belonging to the mycobiota of the cereal rhizosphere. The fungus is
able to metabolize benzoxazolin-2-(3H)-one and a variety of its derivatives including higher plant detoxification products, microbial degradation products and
the chemically rather stable 2-amino-(3H)-phenoxazin-3-one. D. stemonitis can use all of these compounds as sole C-sources but their utilization, especially that of microbial degradation products
and 2-amino-(3H)-phenoxazin-3-one, seems to be highly energy consuming, resulting in slow mycelium growth and a change of colony morphology.
Benzoxazolin-2-(3H)-one derived compounds induce the synthesis of different isoforms of a glycosylated protein with sequence homologies to the
endo-1,3-β-glucanase Asp f2, an allergen from Aspergillus fumigatus and other Asp f2-like proteins e.g., from Verticillium dahliae or PRA1 antigen from Candida albicans. The induction of the protein is regarded as a stress response. 相似文献
102.
103.
为了实现污水处理的深度脱氮除磷及蛋白质源污泥增量,分别采用生物吸附/A~2O和生物吸附/MBR/硫铁自养反硝化工艺进行对比试验研究.结果表明,生物吸附工艺可以快速富集进水中的大部分有机物,剩余污泥采用厌氧发酵方式处理,用于生产优质碳源.两套污水处理工艺均获得了优质水质,出水氨氮、总氮和总磷分别达到5、7和0.4 mg·L~(-1)以下.优质碳源投加到A~2O和MBR工艺段,碳源环境的改善使得污泥增长率和氮的同化比例显著提高,第4阶段污泥产率分别达到0.59和0.49 g·g~(-1)(以每g COD产VSS量(g)计),氮的同化率分别达到66%和59%.此外,污泥中蛋白质及氨基酸含量也显著增长,A~2O工艺段增长率分别为34.7%和31.2%,MBR工艺段相应的增长率分别为19.7%和18.3%,实现了蛋白质源污泥的增量,为污泥资源化利用提供了优质原料. 相似文献
104.
Across West and Central Africa, wildlife provides a source of food and income. We investigated the relation between bushmeat hunting and household wealth and protein consumption in 2 rural communities in Bioko Island, Equatorial Guinea. One village was dedicated to commercial hunting, the other trapped game primarily for food. We tested whether commercial‐hunter households were nutritionally advantaged over subsistence‐hunter households due to their higher income from the bushmeat trade and greater access to wild‐animal protein. We conducted bushmeat‐offtake surveys in both villages (captures by hunters and carcasses arriving to each village). Mammals (including threatened primates: black colobus [Colobus satanas], Preussi's guenon [Allochrocebus preussi], and russet‐eared guenon [Cercopithecus erythrotis]), birds, and reptiles were hunted. The blue duiker (Philantomba monticola), giant pouched rat (Cricetomys emini), and brush‐tailed porcupine (Atherurus africanus) contributed almost all the animal biomass hunted, consumed, or sold in both villages. Monkeys and Ogilbyi's duikers (Cephalophus ogilbyi) were hunted only by commercial hunters. Commercial hunters generated a mean of US$2000/year from bushmeat sales. Households with commercial hunters were on average wealthier, generated more income, spent more money on nonessential goods, and bought more products they did not grow. By contrast, households with subsistence hunters spent less on market items, spent more on essential products, and grew more of their own food. Despite these differences, average consumption of vegetable protein and domestic meat and bushmeat protein did not differ between villages. Our results highlight the importance of understanding the socioeconomic and nutritional context of commercial and subsistence bushmeat hunting to correctly interpret ways of reducing their effects on threatened species and to enable the sustainable offtake of more productive taxa. Contrastes en el Sustento y la Ingesta de Proteínas entre Carne de Caza de Subsistencia y Comercial en Dos Aldeas en Isla Bioko, Guinea Ecuatorial 相似文献
105.
K.M.S. Sundaram 《Journal of environmental science and health. Part. B》2013,48(2):295-312
Abstract Effects of azadirachtin (isomer A, AZ‐A) and tebufenozide (TF) on freshwater algae were investigated using indoor aquatic microcosms. AZ‐A and TF were dosed at different concentrations to 10‐L microcosms. Chlorophyll and protein contents of the algae, and the concentrations of the insecticides in water and algae were monitored at intervals of time up to 20 d. Chlorophyll and protein contents in algae were inhibited at treatment levels of 3.0 and 4.5 μg AZ‐A/mL, whereas at 1.5 μg/mL, the chemical stimulated the chlorophyll production. The partition of AZ‐A between water and algae was reversible, and the bioconcentration factor (BCF) was low. In contrast, TF dosed at 0.25 to 0.75 μg/mL stimulated algal growth, probably due to its utilization of carbonaceous and nitrogenous intermediates and other breakdown products of TF as nutrients. The BCF was high and the organism functioned as a sink for the chemical. Extension of the laboratory findings to complex outdoor systems are discussed. 相似文献
106.
A.H. El‐Sebae M.E. Abdel‐Ghanv D. Shalloway M.M. Abou Zeid J. Blancato M.A. Saleh 《Journal of environmental science and health. Part. B》2013,48(6):763-777
Abstract Phosphorylation is an indispensable process for energy and signal transduction in biological systems. AlCl3 at 10 nM to 10 uM range activated in‐vitro [γ‐32P)ATP phosphorylation of the brain (tau) T protein in both normal human or E.coli expressed T forms; in the presence of the kinases P34, PKP, and PKC. However, higher concentrations of ALCl3 inhibited the T phosphorylation with P34, PKP, and PKC to a maximum at 1 mM level. AlCl3 at 100 uM to 500 uM range induced non‐enzymatic phosphorylation of T with γ‐ATP, γ‐GTP, and α‐GTP. AlCl3 activated histone phosphorylation by P34 in a similar pattern. The hyperphosphorylation of T by Al3+ was accompanied by molecular shift and mobility retardation in SDS‐PAGE. This may demonstrate the mechanism of the longterm neurological effect of Al3+ in human brain leading to the formation of the neurofibrillary tangles related to Alzeheimer's disease. 相似文献
107.
108.
This article presents a method to determine the carbon content of biomass, which is formed when degrading biodegradable polymers in an aerobic aqueous test system. Existing methods for determining the carbon content of biomass (e.g., fumigazation, protein assays, dry solids) have several disadvantages when applied for polymer degradation tests. In this work a protein assay based on the Lowry method was used. It was shown that the ratio between protein and carbon content is not constant but depends on the composition of the microbial population, the growth phase, and the substrate supply. This effect was used for the method presented in this article. For determining the carbon content of biomass the absorbance obtained by the Lowry test is correlated directly with the carbon content of biomass in dependence on the duration of the degradation test. The calibration curves are obtained by a mixed population of microorganisms during the course of a degradation test. 相似文献
109.
V. Gopal S. Parvathy P. R. Balasubramanian 《Environmental monitoring and assessment》1997,48(2):117-124
Cyprinus carpio were exposed to two non-essential (Hg and Pb)and two essential (Cu and Ni) heavy metal salts at lethal andsub-lethal concentrations. Blood serum total protein, serum globulinand serum albumin was analysed every 2 hr for 24 hrs andagain at 48 and 72 hrs. Serum protein and globulin level showedan intial sharp increase from 2 to 20 hrs, followed by decline thatextend over a period of 72 hrs. Serum albumin showed an initialimmediate decline from 2 to 4 hrs, followed by an intermittent period of recovery and decline that extend over a period of 72hrs. Both lethal and sub-lethal concentrations of metal salts elicited asimilar pattern of response varying only in magnitude. The use offish blood serum protein, albumin and globulin measurements as general indicators of pollutant stress response isdiscussed. 相似文献
110.
Processing and Physical Properties of Plastics Made from Soy Protein Polyester Blends 总被引:6,自引:0,他引:6
Blending soy protein with polyesters using a polyvinyllactam as a compatibilizer successfully made soy protein-based plastics. The polyesters used to produce blends included polycaprolactone (PCL) and Biomax (a commercial biodegradable polyester). The blends were processed by compounding extrusion and injection molding. Blends containing soy protein/Biomax-poly(vinyl alcohol) had tensile strengths ranging from 16–22 MPa, with samples containing larger percentages of the synthetic polymer exhibiting greater strengths. Blends made from soy protein, Biomax, and PCL had tensile strengths ranging from 27–33 MPa. All the blends had high Young's moduli but demonstrated brittle characteristics as evident from their low elongations at break, ranging from 1.8–3.1%. Plastics made from soy protein/polyester blends exhibited low water absorption and had good stability under ambient conditions relative to the plastics made from soy protein alone. Blends made from soy protein flour produced plastics with the lowest water absorption. 相似文献