Northern wetlands make up a substantial terrestrial carbon sink and are often dominated by decay-resistant Sphagnum mosses. Recent studies have shown that planctomycetes appear to be involved in degradation of Sphagnum-derived debris. Novel trimethylornithine (TMO) lipids have recently been characterized as abundant lipids in various Sphagnum wetland planctomycete isolates, but their occurrence in the environment has not yet been confirmed. We applied a combined intact polar lipid (IPL) and molecular analysis of peat cores collected from two northern wetlands (Saxnäs Mosse [Sweden] and Obukhovskoye [Russia]) in order to investigate the preferred niche and abundance of TMO-producing planctomycetes. TMOs were present throughout the profiles of Sphagnum bogs, but their concentration peaked at the oxic/anoxic interface, which coincided with a maximum abundance of planctomycete-specific 16S rRNA gene sequences. The sequences detected at the oxic/anoxic interface were affiliated with the Isosphaera group, while sequences present in the anoxic peat layers were related to an uncultured planctomycete group. Pyrosequencing-based analysis identified Planctomycetes as the major bacterial group at the oxic/anoxic interface at the Obukhovskoye peat (54% of total 16S rRNA gene sequence reads), followed by Acidobacteria (19% reads), while in the Saxnäs Mosse peat, Acidobacteria were dominant (46%), and Planctomycetes contributed to 6% of the total reads. The detection of abundant TMO lipids in planctomycetes isolated from peat bogs and the lack of TMO production by cultures of acidobacteria suggest that planctomycetes are the producers of TMOs in peat bogs. The higher accumulation of TMOs at the oxic/anoxic interface and the change in the planctomycete community with depth suggest that these IPLs could be synthesized as a response to changing redox conditions at the oxic/anoxic interface.
Cites: Proc Natl Acad Sci U S A. 1985 Oct;82(20):6955-92413450
Cites: J Mol Biol. 1990 Oct 5;215(3):403-102231712
Cites: Appl Environ Microbiol. 1993 Mar;59(3):695-7007683183
Cites: Nucleic Acids Res. 2001 Jan 1;29(1):181-411125085
The biological fate of the fish feed additive, ethoxyquin (EQ) was examined in the muscle of Atlantic salmon during 12 weeks of feeding followed by a 2 weeks depuration period. Parent EQ (1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline), quinone imine (2,6-dihydro-2,2,4-trimethyl-6-quinolone), de-ethylated EQ (6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline) and EQDM (EQ dimer or 1,8'-di(1,2-dihydro-6-ethoxy-2,2,4-trimethyl-quinoline) were found to be the ubiquitous metabolites of dietary EQ, with EQDM as a main metabolite. A rapid decrease in the level of EQ (2.4 days of half-life) was balanced by an increase in EQDM, giving an unchanged net sum following 2 weeks of depuration. The mandatory 14 days depuration period prior to slaughtering of farmed salmon in Norway was not sufficient for complete elimination of EQ-derived residuals. Post depuration, EQDM accounted for 99% of sum of the two compounds in all treatment groups; possible toxicological effects of EQDM are not known. The individual concentrations of EQ and EQDM and their sum are dependent on EQ level in the feed, consequently, their residual concentrations may be controlled. The theoretical amount of EQ and EQDM consumed in one meal of farmed salmon would be under the recommended ADI, provided that the fish were raised on feed with no more than 150 mg EQ/kg feed, which is the EU maximum limit for EQ in fish feed.
There is rising awareness that different arbuscular mycorrhizal (AM) fungi have different autoecology and occupy different soil niches and that the benefits they provide to the host plant are dependent on plant-AM fungus combination. However, the role and community composition of AM fungi in succession are not well known and the northern latitudes remain poorly investigated ecosystems. We studied AM fungal communities in the roots of the grass Deschampsia flexuosa in two different, closely located, successional stages in a northern Aeolian sand area. The AM fungal taxa richness in planta was estimated by cloning and sequencing small subunit ribosomal RNA genes. AM colonization, shoot d (13)C signature, and %N and %C were measured. Soil microbial community structure and AM fungal mycelium abundance were estimated using phospholipid (PLFA) and neutral lipid (NLFA) analyses. The two successional stages were characterized by distinct plant, microbial, and fungal communities. AM fungal species richness was very low in both the early and late successional stages. AM frequency in D. flexuosa roots was higher in the early successional stage than in the late one. The AM fungal taxa retrieved belonged to the genera generally adapted to Arctic or extreme environments. AM fungi seemed to be important in the early stage of the succession, suggesting that AM fungi may help plants to better cope with the harsh environmental conditions, especially in an early successional stage with more extreme environmental fluctuations.
The chemiluminescence of ovarian tumours tissue lipids was studied at various stages of hormonal cancerogenesis. With the growth of the ovarian tumour the biochimiluminescence intensity decreases and becomes minimal in the period of granulous cell formations. The inverse relationship is observed when studying biochimiluminescence of common liver lipids in tumour-bearing animals, which is explained by migration of bioantioxidants from the liver to the tumour. The changes in the biochimiluminescence intensity at various stages of hormonal cancerogenesis is connected with the processes of tumour cells proliferation.
Two hundred ml of milk were obtained from a lactating Stejneger's beaked whale stranded at Ninilchik, Alaska on 21 Oct, 1980. Total solids (41%) were similar to values reported for sperm and belukha whales, while fat (17%) was half as great and crude protein (17%) was 2-4 times greater than in milk of these species. Lactose was not detected. Calcium (0.22%) was greater than reported for pigmy sperm whales but less than for blue whales. Phosphorus (0.07%) was less than for any of the above species. Sodium and potassium concentrations were 0.13% and 0.11%, respectively. Values (microgram/g) for other elements analyzed (magnesium, 42; iron, 35; copper, 2.6; zinc, 1.5; manganese, 0.3; selenium, 0.36) have not been reported for whale milk. Based on SDS-gel electropherograms, this whale milk did not contain a whey protein corresponding to cattle milk alpha-lactalbumin. A blue-green pigment in the milk was identified as biliverdin.
There are good markets for mature pollock roe; however, immature pollock roe is underutilized. The physical and nutritional properties of immature pollock roe (IPR) have not been reported, which limits its potential use as a food ingredient. The objective of this study was to evaluate the physical and nutritional properties of immature pollock roe and soluble and insoluble protein powders made from the immature roe. IPR samples were obtained during the spring pollock harvest from a seafood processing plant in Kodiak, Alaska. Soluble (SP) and insoluble protein (IP) fractions were produced by heating IPR, separating by centrifugation and freeze drying. The protein contents of freeze-dried IPR, SP, and IP were 81.7%, 63.2%, and 83.0%, respectively. The amino acid contents of IPR and IP were similar except for isoleucine and valine. However, the amino acid contents of IPR and IP were different from values for SP. Lipid contents of IPR, SP, and IP were 9.2%, 9.3%, and 11.1%, respectively. Palmitic acid (C16:0; 21.2%), DHA (C22:6omega3; 21.2%), and EPA (C20:5omega3; 19.0%) were the 3 most abundant fatty acids in fresh IPR. Fat adsorption capacity value for SP was significantly higher than IPR and IP (P
The objectives of this study were to examine protein and amino acid composition, lipid and fatty acid composition, along with a range of essential minerals in common Norwegian seaweed species representing the red (Palmaria palmata and Vertebrata lanosa), green (Cladophora rupestris, Enteromorpha intestinalis and Ulva lactuca) and brown (Alaria esculenta, Laminaria digitata, Laminaria hyperborea, Fucus vesiculosus and Pelvetia canaliculata) classes and assess their potential as alternatives to cereals in food and feed. As macroalgae accumulate heavy metals, arsenic, cadmium and mercury were also analyzed.
Proteins ranged from 34 to 123?g?kg(-1) dry weight (DW) and the essential amino acid levels may cover both human and salmonid requirements. Lipids were low (6-58?g?kg(-1) DW), but the red algae had high relative content of long-chained omega-3 fatty acids (32-34 % of the fatty acids). Iodine contents were particularly high in the Laminaria species. Of the heavy metals only arsenic levels may be of concern.
In total, the red alga P. palmata was regarded as the best alternative to cereals in food and feed. For several of the other species, single-component extraction for the ingredients market may be better than using the whole product.
The chemical composition of Norwegian bulk collected goats' milk from the University herd was analysed during one lactation period (30 weeks, 20 samples during 1983). There was considerable variation in chemical composition during the year. Fat content decreased over the first 4 months of lactation and increased during the mountain pasture period. Protein concentration decreased during the first 4 months, and then increased until the end of lactation. Lactose concentration decreased throughout lactation. Casein nitrogen (casein N) was highest at mid lactation and lowest at the beginning and end of lactation. beta-Lactoglobulin N showed the opposite trend. Citrate content showed a significantly quadratic decrease and total ash content an increase with advancing lactation. Mutual significant correlations between total P, K, Na, Ca and Mg were calculated, and all increased throughout lactation. There was significant positive correlation between concentrations of individual medium-chain fatty acids and stage of lactation. They remained more or less constant during the first part of the lactation, decreased to minima when the goats were on pasture, and increased during the last phase of lactation. Concentration of C16 fatty acid was negatively correlated with C18 and C18:1. Goat flavour intensity score and quality flavour score were highest at mid lactation, and positively correlated with the acid degree value.