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1.
1. Studies were conducted with tall oil fatty acids (TOFA) to determine their effect on broiler chicken performance and ileal microbiota. TOFA, a product originating from coniferous trees and recovered by fractional distillation of side-streams from pulp production, mainly comprises free long-chain fatty acids (~90%) and resin acids (~8%). Conjugated linolenic acids and pinolenic acid are characteristic fatty acid components of TOFA.

2. TOFA products at 750 mg/kg feed were tested in two 35-day broiler chicken trials, each using a wheat soya-based diet and with 12 replicate pens per treatment. In both trials, TOFA improved body weight gain at all time points (P < 0.001) and feed conversion efficiency during the first 21 days (P < 0.01). Two different dry TOFA formulations (silica carrier and palm oil coating) were tested and showed performance effects similar to liquid TOFA.

3. Ileal digesta of the broiler chickens was analysed for total eubacteria, Lactobacillus spp., Enterococcus spp., Escherichia coli and Clostridium perfringens on days 14 and 35. TOFA significantly increased total eubacteria and lactobacilli density on day 14 (P < 0.05). There was a significant positive correlation between these bacterial groups and broiler body weight on day 14 (P < 0.01).

4. A numerical reduction in C. perfringens was observed. In vitro growth inhibition studies showed that C. perfringens was strongly inhibited by 10 mg/l TOFA (P < 0.001), while common lactobacilli were resistant to >250 mg/l. The in vitro results were thus in line with in vivo observations.

5. The mechanisms behind the bacterial shifts and their role in performance improvement are unknown. Further purification of TOFA components is needed to identify the effective agents.  相似文献   

2.
The removal of the cyanobacterial peptide toxin microcystin-LR at 4 and 37 degrees C by six commercial probiotic strains and Lactobacillus plantarum strains IS-10506 and IS-20506 isolated from dadih, Indonesian traditional fermented milk, was assessed in this study. The aim was to evaluate the main factors influencing the viability and metabolic activity of the probiotic strains, as well as their capacity to remove microcystin-LR. Both L. plantarum strains isolated from dadih, as well as Bifidobacterium lactis strains Bb12 and 420, were shown to be more resistant, and >85% remained viable in phosphate-buffered saline (PBS) solution for 48 h of incubation at either temperature, while the viability of the other four commercial bacteria decreased markedly over time. The effect of glucose on viability and removal of toxin was shown to be a strain-specific and strain-dependent property, but in general, the efficiency of microcystin-LR removal increased when glucose was added to the solution. A maximum removal of 95% was observed for L. plantarum strain IS-20506 (37 degrees C, 10 (11) colony-forming units mL(-1)) with 1-2% glucose supplementation and 75% in PBS alone.  相似文献   
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4.
A species trial with 14 eucalypt species with randomized complete blocks design was planted on Imperata cylindrica dominated grassland in South Kalimantan, Indonesia in January 1987. The site was prepared mechanically. No fertilizers were used. At the age of three years E. camaldulensis had clearly the highest survival rate (95%) and mean annual increment (5.9 m3ha–1a–1) compared with the other species tried. It was followed by E. urophylla, E. deglupta, E. pellita, E. tereticornis, E. alba, E. torelliana, E. intermedia, E. grandis and E. pilularis. Four other species, E. phaeotricha, E. resinifera, E. cloeziana and E. microcorys died either in the nursery or immediately after planting. All the eucalypts tried had narrow crowns and open canopies. It is suggested that eucalypts are not recommendable for grassland reforestation under minimum plantation tending. Effects of intensive weeding, spacing, fertilizing and performance in second rotation or mixed stands should be tested to elaborate the suitability of eucalypts on grasslands.  相似文献   
5.
The prolamins of wheat, rye, and barley contain structures that are harmful to gluten-sensitive people, and an extensive degradation of these prolamins during food processing might eliminate this problem. Sourdough fermentation is a cereal food process during which some protein degradation occurs. In this study, the prolamin hydrolysis that occurred in a high-proteolytic-activity germinated-wheat sourdough (GWSD) was compared with that of wheat sourdough systems which contained moderate or no proteolytic activities. Virtually all of the wheat prolamins (gliadins and glutenins) were degraded during the GWSD fermentation. Quantification of its prolamin levels confirmed that extensive prolamin hydrolysis had occurred in the GWSD. This hydrolysis was attributed to the cysteine proteinase activities of the germinated wheat. The use of high-proteolytic sourdoughs in baking could make it possible to prepare new low-prolamin cereal-based products for use by gluten-sensitive people, who could then diversify their diets by including these whole-grain containing products into their every-day diets.  相似文献   
6.
Functional properties of conventional oat materials are relatively poor with respect to foam and emulsion formation and stabilization. This is largely due to the poor solubility of oat proteins and the presence of lipids in aqueous extracts of oats. In the experimental part of this study, extracts were prepared from different type oat flours (oat endosperm flour, oat fine flour, CO2-defatted whole oat flour and CO2-defatted oat flour) with a buffered aqueous extraction procedure at acidic (pH 4.5 and 6.5) and basic (pH 8.5 and 10.5) regions. The solubility of proteins was the highest at pH 10.5 and NaCl concentration of 2%. Among the extracts, CO2-oat flour showed improved foaming and emulsifying properties at basic pH values. The presence of 0.1% NaCl resulted in the lowest foam volumes, but the emulsion activity and stability values being the highest. Sucrose addition resulted in increased foam and emulsion stability of suspensions. Heat treatment at 80 °C impaired foam properties, whereas the stability of emulsions increased with the increase in temperature from 20 °C to 80 °C. CO2-extracted oats can be useful raw materials in beverages and other aqueous applications where protein functionality plays an important role.  相似文献   
7.
The complete carbon budget and the turnover rate of assimilated carbon of ectomycorrhizal Scots pine seedlings growing on natural humus were determined in microcosm conditions. The main aim was to improve understanding of the partitioning of the assimilated carbohydrates within seedlings associated with multiple ectomycorrhizal fungi, and to discover carbon dynamics of the mycorrhizosphere.Plant photosynthesis and below-ground respiration were measured in order to obtain the actual carbon assimilation and respiration rates at the time of measurements. Soon after the photosynthesis and respiration rate measurements the seedlings were pulse-labeled with 14CO2 to follow carbon allocation to different plant, fungal and soil compartments and rhizosphere respiration. Long-term carbon allocation during the entire life span of the seedlings was estimated by measuring plant and mycorrhizal root-tip biomass. The ectomycorrhizal community was analyzed using morphotyping and ITS-sequencing.The 14C label was detected in rhizosphere respiration after 12 h and it peaked between 36 and 60 h after labeling. More than half of the assimilated carbon was allocated below-ground as biomass or respiration and higher mycorrhizal biomass increased the below-ground carbon turnover. The presence of Suillus variegatus affected the plant carbon balance in several ways. When S. variegatus was present, the below-ground respiration increased and this carbon loss was compensated by higher photosynthetic activity. Other fungal species did not differ between each other in their effects on carbon balance. Our findings indicate that some root-associated mycorrhizal fungal symbionts can significantly alter plant CO2 exchange, biomass distribution, and the allocation of recently photosynthesized plant-derived carbon.  相似文献   
8.
The primary objective of this monitoring is to detect long-term Long-Range Transboundary Air Pollution (LRTAP) induced changes in the water quality of small lakes, throughout Finland, with low conductivity. The monitored lakes (n=171, sampled every autumn since 1990 and in 1987) have a smaller watershed (usually headwater or seepage lakes), a larger lake/catchment ratio, and lower base cation concentrations, alkalinity and pH than Finnish lakes on average. The monitoring network provides background data for air pollution dose/response studies, critical load calculations and for the modelling of acidification scenarios. The declining sulphate deposition seems to be reflected in small headwater lakes all over southern and central Finland as a lowering of the sulphate concentration in the waters. Nitrate concentrations in these lakes have been typically low in the autumn. The base cation concentration is not generally declining, as it is in deposition in many areas. The sulphate concentration in lakes has declined more than base cations. Hydrologically, the recent years have been quite variable because of varying annual precipitation. The variation in alkalinity and pH in typical Finnish lakes is dependent on the content of humic material derived from catchments. The monitoring period is too short to reveal consistent trends in major ion chemistry. However, signs of improvement in recent years can be seen; in comparing 1993 to 1987, years with similar organic acidity and base cations, it seems that the sulphate decline in lakes monitored is compensated by a significant rise in both alkalinity and pH.  相似文献   
9.
Since the early 1980s, the acidic deposition in the northern Europe has decreased substantially. This has resulted in corresponding improvements of the water quality in some acid sensitive small lakes of southern Finland. Among the fish of these lakes, the first signs of recovery were recorded in the early 1990s, when the European perch (Perca fluviatilis L.) started to reproduce in some sparse populations. Since then, the reproduction of perch has been successful in several years. The appearance of strong year-classes in lakes earlier almost empty of fish indicates recovery. This development has resulted in increased population densities, decreased mean sizes of fish and decreased growth rates. In a more acid sensitive species, roach (Rutilus rutilus (L.)), no clear indications of recovery have been recorded this far. However, schools of small roach (age 1+) were observed in the summer of 1998 in two acidic lakes that were inhabited by sparse roach populations during 1985–1995.  相似文献   
10.
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