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Biomedical subjects

J Knuutinen

Publications and source records attributed to J Knuutinen.

10 recordsLinked to original sources
PubMed2005

Protein metabolism and strength performance after bovine colostrum supplementation.

This study was designed to determine the responses of muscle protein, serum amino acids, and strength performance to bovine colostrum supplementation in physically active men. The rest (R) group (n = 6) and the exercise (E) group (n = 6) carried out twice a 2-week experiment randomly assigned in a double-blind fashion with either placebo (PLA; consuming daily 20 g maltodextrin) or bovine colostrum (COL; consuming daily 20 g colostrum supplement) treatment with one month between. On the test day after the treatment period the measurements were carried out in fasting conditions and E carried out a strength training session (STS). The methods involved the infusion of ring-(2)H(5)-phenylalanine, femoral arterial and venous blood sampling, and biopsies from the vastus lateralis muscle. Serum concentration of essential amino acids during recovery was greater (p < 0.05) in the COL groups compared with the PLA groups. Both muscle protein synthesis and breakdown increased (p < 0.05) with COL. There were no differences in phenylalanine net balance or strength performance between the PLA and COL groups. It was concluded that a 2-week supplementation with bovine colostrum in physically active men increases serum concentration of essential amino acids but has no effect either on strength performance or protein net balance in fasting conditions during recovery after STS.

Adult↗
PubMed1999

Pyrolysis of humic acids from digested and composted sewage sludge

Humic acids (HAs) were extracted from four digested sewage sludge samples composted for four months, one, two and four years. HAs were pyrolyzed at three different temperatures applying both conventional and in situ methylation (ISM) pyrolysis. The pyrolysates were analyzed using gas chromatography-mass spectrometry (GC/MS). Derivatization (ISM) and pyrolysis temperature had dramatic effects on the composition and relative amounts of the pyrolysates. Among the derivatized HA fragments aliphatic compounds prevailed under all the pyrolysis conditions tested. Aromatic substances consisting mainly of guaiacyl-type compounds were detected in higher abundances only at elevated temperatures. Without ISM the contribution of aromatic structures to the total pyrogram was considerably greater than that of the aliphatics. Increase of the pyrolysis temperature from 450 degrees C to 600 degrees C had smaller effect on the proportions and composition of the compounds studied than increase from 350 degrees C to 450 degrees C.

Journal Article↗
PubMed1998

Identification of fish species by reversed-phase high-performance liquid chromatography with photodiode-array detection.

A method for the separation of sarcoplasmic fish proteins by RP-HPLC is described. The procedure revealed significant differences useful for reliable identification of fish species. Sixteen of the most common Finnish freshwater fish species were differentiated by species-specific HPLC chromatograms obtained using photodiode-array detection (PAD) at 200-350 nm. The analytical column was a Hi-Pore RP-304 reversed-phase column. The separation was performed by a linear gradient of acetonitrile and water with a small amount of trifluoracetic acid (TFA). Star-symbol plots were constructed from the chromatograms to visualize the data. Clearly different HPLC protein profiles for most fish species were obtained. The chromatograms of salmonoids show similarities, whereas the protein profiles of cyprinids are dissimilar. Minor intraspecific differences were obtained for three types of powan (Coregonus lavaretus).

Animals↗
PubMed1998

Pyrolysis-GC-MS and CuO-oxidation-HPLC in the characterization of HMMs from sediments and surface waters downstream of a pulp mill.

High molecular mass fractions of lignin and humic compounds in sediments and waters downstream of a pulp mill were characterized applying pyrolysis-gas chromatography-mass spectrometry. The results were compared to those obtained using reversed phase HPLC on the cupric oxide oxidation products. The chromatographic data of both pyrolysis and cupric oxide oxidation were also subjected to the principal component analysis (PCA). The sediment samples and fractions obtained by ultrafiltration of river water samples were freeze dried prior to characterization. The sediment samples were also extracted using 2 M sodium hydroxide solution. The extracts were ultrafiltrated, freeze dried and compared to the freeze dried original sediments using the procedures mentioned above. The amounts of HMMs obtained from the sediments ranged from 62 mg to 97 mg per one gram of sediment. Gel permeation chromatography was applied to samples obtained from sediments by extraction with tetrahydrofuran. The weight average molecular weights of these fractions were in the range of 1500-2300 amu.

Chromatography, High Pressure Liquid↗
PubMed1994

Characterization of the humic material formed by composting of domestic and industrial biowastes. Part 1. HPLC of the cupric oxide oxidation products from humic acids.

The changes induced by humification of anaerobically digested sewage sludge, source separated biowaste, and pulp mill biosludge were determined by extracting the fractions of bitumen and humic and fulvic acids from the samples of fresh and humified composts. In all cases, a distinct decrease in the amount of bitumen could be detected during humification. The amount of humic acids increased in sewage sludge and biowaste samples, but decreased in pulp mill biosludge sample during humification. The humic acids were degraded by CuO oxidation and the phenolic degradation products were analysed by reversed-phase high-performance liquid chromatography. The yield of these aromatic degradation products was in the range 0.9-2.0% for each sample. The main phenolic degradation products were 4-hydroxybenzoic acid, vanillic acid, 4-hydroxybenzaldehyde, vanillin, syringaldehyde, and acetovanillone. Two lignin dimers, dehydrodivanillin and dehydrodiacetovanillone, were also identified.

Chromatography, High Pressure Liquid↗
PubMed1985

Pyrolysis products of PCBs.

Model compound studies which were previously done for impurities and environmental residues of chlorophenols and for wastes of chlorination processes were extended to the impurities and pyrolysis products of polychlorinated biphenyls (PCBs). Model compounds were commercial products or synthesized and their structures proven by spectroscopic methods. These models were used as analytical reference substances in GC/ECD and GC/MS studies of the pyrolyzed PCB samples. In addition to previously known neutral components like polychlorinated dibenzofurans (PCDFs), chlorophenolic substances, especially polychlorophenols (PCPs) and polychlorinated biphenylols (PCB-OHs) were observed as major pyrolysis products of PCBs. Capacitor fires are suggested to produce in many cases chlorophenols which are major toxic hazards to people.

Chromatography, Gas↗
PubMed1982

The mutagenicity of some edible mushrooms in the Ames test.

The mutagenic activity of five wild and two cultivated species of edible mushrooms was studied in the Ames Salmonella/microsome test system. The wild mushrooms tested were four species of the genus Lactarius (L. necator, L. torminosus, L. helvus and L. rufus) and bolete (Boletus edulis). The cultivated species were champignon (Agaricus bisporus) and shiitake (Lentinus edodes). All the mushrooms were mutagenic to tester strains sensitive to base-pair substitution mutagens, and L. necator, L. rufus and B. edulis also had some frameshift activity. Metabolic activation was not required and the mutagenic activity could be detected even in boiled mushroom extracts. After fractionation with organic solvents (ethanol followed by diethyl ether) the activity was recovered in the ether phase as well as the aqueous phase in the case of L. necator, but remained in the aqueous phase of the A. bisporus and Lentinus edodes extracts.

Basidiomycota↗
PubMed1977

Thin-layer chromatography of chlorinated catechols.

The thin-layer chromatography of catechol and six chlorinated catechols has been studied on five adsorbents. Acetic acid in the developing solvent was essential for the production of sharp zones. The best separation of the individual compounds occurred on alumina, whereas silica gel appeared to be good for group separation (clean-up) from other compounds.

Catechols↗