Polymerisation of added coniferyl alcohol by inherent xylem peroxidases and its effect on fungal decay resistance of Norway spruce     

Sanni Raiskila  Kurt Fagerstedt  Tapio Laakso  Pekka Saranpää  Mia Löija  Leena Paajanen  Riitta Mahlberg  Anne-Christine Ritschkoff 《Wood Science and Technology》2006,40(8):697-707

It is known that active peroxidase isozymes exist in mature wood of Norway spruce (Picea abies L. Karst.) and that they remain active for years and are found even in the heartwood (in Scots pine), where all cellular activity has ceased. This peroxidase activity was utilised in the impregnation of wood blocks with a natural monolignol, coniferyl alcohol and hydrogen peroxide. The hypothesis was that the internal wood peroxidases would oxidise the added monolignol and bind it stably into the cell wall matrix, which could hinder fungal decay. Since coniferyl alcohol is not very soluble in water, the impregnation was done under vacuum with an acetone–water solution containing 10% coniferyl alcohol and 0.4 mM H₂O₂ at room temperature (ca. 0.02 g of coniferyl alcohol was added to 1 g of wood). After impregnation, dimers of coniferyl alcohol and free coniferyl alcohol were found in acetone extracts with GC–MS analysis. Penetration of coniferyl alcohol and non-extractable reaction products were studied from the wood blocks with FTIR PAS technique. The wood samples treated were also subjected to a fungal decay test with Coriolus versicolor. This treatment hindered fungal decay in a 60-day experiment and led to a dry weight loss of 8.8% in comparison with 19.9% in the control. The reactions of coniferyl alcohol and H₂O₂ in the presence of peroxidases are discussed as well as the use of monolignols to increase wood decay resistance.  相似文献   

Predicting spring phenology and frost damage risk of Betula spp. under climatic warming: a comparison of two models   总被引：1，自引：0，他引：1  

Linkosalo T  Carter TR  Häkkinen R  Hari P 《Tree physiology》2000,20(17):1175-1182

Timing of bud burst and frost damage risk for leaves of Betula spp. in response to climatic warming in Finland was examined with two models. In the first model, ontogenetic development in spring was triggered by an accumulation of chilling temperatures. The second model assumed an additional signal from the light climate. The two models gave radically different estimates of frost damage risk in response to climate warming. The chilling-triggered model forecast a significant and increasing risk with increased warming, whereas the light-climate-triggered model predicted little or no risk. The chilling-triggered model is widely applied in phenological research; however, there is increasing experimental evidence that light conditions play a role in the timing of spring phenology. Although it is not clear if the light response mechanisms are appropriately represented in our model, the results imply that reliance on a light signal for spring development would afford a degree of protection against possible frost damage under climate warming that would not be present if chilling were the sole determinant. Further experimental tests are required to ascertain the light-related mechanisms controlling phenological timing, so that credible model extrapolations can be undertaken.  相似文献   

Non-industrial private forest owners' willingness to supply forest-based energy wood in the South Savo region in Finland     

Sinikka Mynttinen  Kalle Karttunen  Tapio Ranta 《Scandinavian Journal of Forest Research》2014,29(1):41-50

The consumption of energy wood in Finland has increased dramatically since the early 2000s, and the region of South Savo is a bellwether for its usage across the country. This increase is partly due to the national policy of sustainable energy, region's wealth of forests but is also dependent on non-industrial private forest owners (NIPF) deciding to sell energy wood. In this study, a survey with a structured questionnaire was conducted among the NIPFs in the region of South Savo to enlarge the understanding of their willingness to sell energy wood in the future and adopt new approaches to forestry that involves energy wood thinning as well as their current production of energy wood. Moreover, the factors influencing forest owner's motivations relating to energy wood thinning as well as information needs were analysed with multivariate techniques. The results show that almost half of the forest owners in the South Savo region had not sold energy wood. However, forest owners within the region generally had positive attitudes towards selling small-sized energy wood and forestry methods that involve energy wood thinning. Moreover, forest owners' willingness to sell different types of energy wood varied, depending on their background. The study suggests that the increase in supply of energy wood presumes both intensified extension services for forest owners and markets that are better organised than at the moment. The results may also prove beneficial in informing policy-makers regarding which specific target group(s) to focus on when promoting energy wood sales among NIPFs and which aspects of energy wood harvesting and sales to promote.  相似文献   

Pathogenic,Enterotoxin-Producing Staphylococci in Mink Feed and Mink Feed Raw Materials     

Tapio Juokslahti  Seppo Lindroth  Aimo Niskanen 《Acta veterinaria Scandinavica》1980,21(4):516

Samples of 51 mink feeds and 101 raw material batches were analysed for pathogenic staphylococci. Of the feed samples 37 % were contaminated with pathogenic staphylococci, the mean count being 3.02 log CFU (colony forming units)/g and the highest count being 4.48 log CFU/g of feed. Of the raw materials investigated, slaughter-house offals were most frequently contaminated and contained highest counts of S. aureus, 60 % of the samples being positive with a mean log count of 3.86/g and a maximum of 5.70/g. Forty-eight staphylococcal isolates were tested for eniterotoxin production. Toxin A, B or G were produced by eight isolates, A being the most common. None of the isolates produced B or E toxins.  相似文献   

The Effect of the Bacteriological Status of Feed on Some Haematological and Blood Chemical Data on Mink     

Tapio Juokslahti 《Acta veterinaria Scandinavica》1980,21(4):504

Blood samples from 100 minks from a research farm using bacteriologically high quality feed and from 55 minks from another farm supplying bacteriologically inferior feed, as well as from nine minks from Denmark from two farms providing still better quality feed than both Finnish farms – all minks apparently clinically healthy – were analyzed for some haematological and chemical data: total leucocyte count, haemoglobin, ornithine carba-moyltransferase (OCT), alkaline phosphatase (AP), alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), γ-glutamyl-transferase (Γ-GT), total bilirubin and creatinine. The Finnish minks supplied with high quality feed had more optimal values of total leucocytes, haemoglobin, OCT, AP and creatinine than minks receiving feed with higher bacterial contamination. The Danish minks had better blood values in the investigated parameters except for lower haemoglobin and total bilirubin, which showed no significant difference.  相似文献   

Bacteriological Quality of Ready-Mixed Mink Feed in Finland     

Tapio Juokslahti 《Acta veterinaria Scandinavica》1978,19(4):520

Frozen samples of Finnish ready-mixed mink feed were analyzed for total bacterial count, the number of faecal streptococci, the coliform count, the number of haemolytic bacteria and the number of sulphite-reducing bacteria. The investigation comprised 242 feed samples from 38 central kitchens and larger private farm kitchens, the combined feed production of which is about 85 % of the yearly feed production of Finland.Of all samples 48.3 % had a total bacterial count of 10⁶ … 6} × 106 bacteria per g of feed. The total bacterial count was relatively constant during the first four production periods of the year (December-August) and was elevated during the last period (September-November). The percentage of samples containing less than 2.5 × 10⁴ faecal streptococci per g of feed was 49.8 %; 62 % of the samples contained less than 2.5 × 10⁴ coliform bacteria per g. The content of coliform bacteria was lowest during the third production period (May); 48.5 % of the samples contained 5 × 10³ … 10⁵ haemolytic bacteria per g, and 4.6 % were negative. The content of haemolytic bacteria was relatively constant during the whole production year; 52.6 % of the feed samples contained 5 × 10³ … 10⁵ sulphite-reducing bacteria per g, and 17.2 % were negative. The mean content of sulphite-reducing bacteria was lowest during the second production period (March-April).The results are discussed and compared with corresponding results from Norway and Denmark.  相似文献   

Sole ulcers in Finnish dairy cattle     

Minna Kujala  Ian R. Dohoo  Minna Laakso  Christian Schnier  Timo Soveri 《Preventive veterinary medicine》2009,89(3-4):227-236

The Finnish Healthy Hooves project was set up to determine the frequency of, and risk factors for various hoof lesions in Finnish dairy herds. Data were collected in the years 2003 and 2004. A large dataset of over 74,000 cow-level observations recorded by hoof trimmers was merged with production data from the Finnish Agricultural Data Processing Centre Ltd. Ultimately, data from a single lactation from each of 16,792 cows in 703 herds were used for the analyses in this paper. Three-level hierarchical logistic models with hoof trimmer and farms (within hoof trimmer) as random effects were fit to data sets of tie stall (TS) and loose housing (LH) herds separately. The outcome of interest was the presence or absence of a sole ulcer in one or more legs of a cow during the lactation of interest.Cows examined once had a risk of sole ulcer 5.23% in tie stall herds and 7.58% in LH herds. As the number of examinations increased the odds of a diagnosis of sole ulcer increased substantially (2 and 3+ examinations had odds ratios (ORs) of 1.42 and 3.42 in TS herds and 2.77 and 6.89 in LH herds). Breed had a large effect on the risk of sole ulcer with Holsteins 2.89 times more likely to be affected than Ayrshires in TS herds and 2.94 times in LH herds. In TS herds, the presence of other hoof lesions such as haemorrhages (OR = 2.97), heel-horn erosions (OR = 2.10) and corkscrew claw (OR = 2.83) increased the risk of a sole ulcer developing. In LH herds, only haemorrhages (OR = 1.80) were a significant risk factor when parity was ≥2. In TS herds, use of mats (compared to hard flooring) significantly reduced the risk of sole ulcers (OR = 0.49). The effect of parity on the risk of sole ulcer was greatest when parity ≥4 but this effect was only significant in tie stalls (OR = 1.86).When analyses were restricted to cows with parity ≥2, similar results were obtained for the risk factors identified above. In addition, parity became highly significant in TS and LH (OR 2.31 and 2.23, respectively when parity was 4+). In TS herds, herd average milk production was significantly associated with a decrease risk of sole ulcer (OR = 1.28 per 1000 kg decrease) but there was no effect of production at the cow level (measured as deviation from the herd mean). No significant effects of production were observed in LH herds.  相似文献   

Positional distribution of conjugated linoleic acid in triacylglycerol of Saccharomyces cerevisiae     

Jaakola S  Vahvaselkä M  Laakso S 《Journal of agricultural and food chemistry》2006,54(15):5611-5616

Saccharomyces cerevisiae was cultivated in the presence of cis-9,trans-11 or trans-10,cis-12 isomers of free conjugated linoleic acid (CLA), and the effects of the isomers on the regioisomerisms of triacylglycerol (TAG) of the yeast were elucidated. Both isomers constituted about 34% of all fatty acids and increased drastically the number of different TAG species. Nearly all of the species contained CLA in at least one sn-position. In the most abundant species analyzed (20% of total species), the cis-9,trans-11 isomer appeared in combination with monounsaturated fatty acids (C16:1, C:18:1) whereas trans-10,cis-12 isomer was most frequently present with a medium chain fatty acid (C10:0 or C12:0) in the sn-2 position and C16:0 in one of the end positions (14% of total species). With either isomer, the amount of TAG species in which CLA encompassed all sn-positions was ca. 4%. Thus, S. cerevisiae can be used to produce edible single cell oil characterized by very heterogeneous distribution of CLA among the different TAG species.  相似文献   

Microbially safe utilization of non-inactivated oats (Avena sativa L.) for production of conjugated linoleic acid     

Vahvaselkä M  Lehtinen P  Laakso S 《Journal of agricultural and food chemistry》2006,54(3):963-967

A microbially safe process for the enrichment of conjugated linoleic acid (CLA) in oats was developed. The process consists of hydrolysis of oat lipids by non-inactivated oat flour, followed by propionibacterium-catalyzed isomerization of the resulting free linoleic acid to CLA. The first stage was performed at water activity (a(w)) 0.7, where hydrolysis of triacylglycerols progressed efficiently without growth of the indigenous microflora of flour. Thereafter, the flour was incubated as a 5% (w/v) aqueous, sterilized slurry with Propionibacterium freudenreichii ssp. shermanii. The amount of CLA produced in 20 h was 11.5 mg/g dry matter corresponding to 116 mg/g lipids or 0.57 mg/mL slurry. The oat flour had also the capability to hydrolyze exogenous oils at a(w) 0.7. Sunflower oil, added to increase linoleic acid content in triacylglycerols 2.7-fold, was hydrolyzed rapidly. Isomerization of this oil-supplemented flour as a 5% slurry gave final CLA content of 22.3 mg/g dry matter after 50 h of fermentation, corresponding to 118 mg/g lipids or 1.14 mg/mL slurry. Storage stability of CLA in fermented oat slurries at 4 degrees C was good.  相似文献   

Effects of vatinoxan on cardiorespiratory function and gastrointestinal motility during constant-rate medetomidine infusion in standing horses     

H. Tapio  M. R. Raekallio  A. Mykkänen  S. Männikkö  M. Scheinin  R. C. Bennett  O. Vainio 《Equine veterinary journal》2019,51(5):646-652

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