Enantioselective reduction of acetyldimethylphenylsilane: A screening with thirty strains of microorganisms

Summary Thirty strains of microorganisms (bacteria, yeasts, fungi and green algae) were tested as resting free cells for their ability to transform acetyldimethylphenylsilane (1) enantioselectively into (R)-(1-hydroxyethyl)dimethylphenylsilane [(R)–2]. The biotransformations were monitored by GC (packed OV-17 column) and the enantiomeric purities of the products isolated were determined by HPLC (cellulose triacetate column, UV detection). All microorganisms tested were found to reduce 1 enantioselectively to give (R)-2. Under the test conditions used, the yeastTrigonopsis variabilis (DSM 70714) was found to exhibit the highest specific activity (1.5 mg product x g cell wet mass^–1 x min^–1), whereas the highest enantioselectivities were observed for the bacteriaAcinetobacter calcoaceticus (ATCC 31012) (>95% ee),Brevibacterium species (ATCC 21860) (90% ee) andCorynebacterium dioxydans (ATCC 21766) (>95% ee), the yeastCandida humicola (DSM 70067) (90% ee), the fungusCunninghamella elegans (ATCC 26269) (94% ee), as well as the cyanobacteriumSynechococcus leopoliensis (94% ee). From the green algae tested,Chlamydomonas reinhardii showed the highest enantioselectivity (85% ee).     

Biocatalysts for production of chiral epoxides

Summary A number of bacterial strains, representing a range of genera, were isolated in pure culture with ethene or propene as the sole source of carbon and energy. The organisms included Aerococcus, Alcaligenes, Micrococcus and Staphylococcus spp. and a variety of Gram-negative, Gram-positive and Gram-variable mesophilic rods/ coccobacilli not yet identified. This suggests that the ability to utilize gaseous olefins is more widespread in nature than previously recognised. All 18 organisms tested stereospecifically formed R-1,2-epoxypropane (enantiomeric excess, ee=90–96%), R-1,2-epoxybutane (ee=90–98%) and trans-(2R,3R)-epoxybutane (ee=64–88%) from the corresponding olefins. In addition to Micrococcus sp. M90C, the substrate specificities of six other organisms were studied. The pattern of reactivity for the group of four ethene (M26, M90C, M93A, M186)- and two propene (M142, M156)-utilizers differed from that found with peracids, whereas the chemical reactivity of the substrate appeared to affect enzymatic epoxidations in Staphylococcus sp. M97B. Offprint requests to: M. Mahmoudian     

Improvement of natural isolates of <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis> strains for synthesis of a chiral building block using classic genetics

The asymmetric bio-reduction of 4-chloro-acetoacetic-acid-ethyl-ester to the pharmaceutical building block (S)-4-chloro-3-hydroxybutanoate-ethyl-ester requires the utilization of an enantioselective robust biocatalyst. Some of the natural Saccharomyces cerevisiae strains, isolated from Mount Carmel National Park in Israel, were characterized as resistant to environmental stress. Nevertheless, these strains showed relatively low enantiomeric-excess (ee), while a laboratory strain, Y103, exhibited a selectivity of 98% ee. The enantioselective lab strain was crossed with the multi-stress resistant environmental isolate (93% ee) followed by backcross with Y103, to subsequently obtain a haploid offspring of backcross-1, exhibiting both high multi-stress resistance and high enantioselectivity (98% ee). Introducing osmotic (1 M NaCl), oxidative (0.6 mM H₂O₂) and thermal stress (44°C) to growing cultures of the enantioselective parent, resulted in a decrease of 24–32% in specific activity, while the enantioselectivity of the stress-resistant parent decreased by 4–12% ee. Unlike its original parental strains, the new strain maintained constant specific activity and enantioselectivity when introduced to the various stress factors. This work shows that the classic introgression method, can serve as a viable approach for creating a robust enantioselective biocatalyst, designed for industrial production of chiral compounds.     

Field metabolic rate and water turnover of the numbat (<Emphasis Type="Italic">Myrmecobius fasciatus</Emphasis>)

The numbat (Myrmecobius fasciatus) is a diurnal and exclusively termitivorous marsupial. This study examines interrelationships between diet, metabolic rate and water turnover for wild, free-living numbats. The numbats (488±20.8 g) remained in mass balance during the study. Their basal metabolic rate (BMR) was 3.6 l CO₂ day^–1, while their field metabolic rate (FMR) was 10.8±1.22 l CO₂ day^–1 (269±30.5 kJ day^–1). The ratio FMR/BMR was 3±0.3 for numbats. We suggest that the most accurate way to predict the FMR of marsupials is from the regression log FMR=0.852 log BMR+0.767; (r²=0.97). The FMR of the numbat was lower than, but not significantly different from, that of a generalised marsupial, both before (76%) and after (62–69%) correction for the significant effect of phylogeny on FMR. However the numbat's FMR is more comparable with that of other arid-habitat Australia marsupials (98–135%), for which the regression relating mass and FMR is significantly lower than for nonarid-habitat marsupials, independent of phylogeny. The field water turnover rate (FWTR) of free-living numbats (84.1 ml H₂O day^–1) was highly correlated with FMR, and was typical (89–98%) of that for an arid-habitat marsupial after phylogenetic correction. The higher than expected water economy index for the numbat (FWTR/FMR=0.3±0.03) suggests that either the numbats were drinking during the study, the water content of their diet was high, or the digestibility of their termite diet was low. Habitat and phylogenetic influences on BMR and FMR appear to have pre-adapted the numbat to a low-energy termitivorous niche.Abbreviations BMR basal metabolic rate - FMR field metabolic rate - EWL evaporative water loss - FWTR field water turnover rate - MR metabolic rate - PVR phylogenetic vector regression - RER respiratory exchange ratio - T_a ambient temperature - T_b body temperature - TBW total body water - CO₂ rate of carbon dioxide production - O₂ rate of oxygen consumption - WEI water economy index - WER water efflux rate - WIR water influx rateCommunicated by I.D. Hume     

Dietary assimilation and the digestive strategy of the omnivorous anomuran land crab<Emphasis Type="Italic"> Birgus latro</Emphasis> (Coenobitidae)

On Christmas Island, Indian Ocean, the diet of robber crabs, Birgus latro (Linnaeus) was generally high in fat, storage polysaccharides or protein and largely comprised fruits, seeds, nuts and animal material. The plant items also contained significant amounts of hemicellulose and cellulose. In laboratory feeding trials, crabs had similar intakes of dry matter when fed artificial diets high in either fat or storage polysaccharide, but intake was lower on a high protein diet. Assimilation coefficients of dry matter (69–74%), carbon (72–81%), nitrogen (76–100%), lipid (71–96%) and storage polysaccharide (89–99%) were high on all three diets. B. latro also assimilated significant amounts of the chitin ingested in the high protein diet ( 93%) and hemicellulose (49.6–65%) and cellulose (16–53%) from the high carbohydrate and high fat diets. This is consistent with the presence of chitinase, hemicellulase and cellulase enzymes in the digestive tract of B. latro. The mean retention time (27.2 h) for a dietary particle marker (⁵⁷Co-labelled microspheres) was longer than measured in leaf-eating land crabs. The feeding strategy of B. latro involves the selection of highly digestible and nutrient-rich plant and animal material and retention of the digesta for a period long enough to allow extensive exploitation of storage carbohydrates, lipids, protein and significant amounts of structural carbohydrates (hemicellulose, cellulose and chitin).Communicated by I.D. Hume     

Studying allozyme variation in sexual and apomictic <Emphasis Type="Italic">Taraxacum</Emphasis> and <Emphasis Type="Italic">Pilosella</Emphasis> (Asteraceae) populations

Allozyme spectra of peroxidase, esterase, superoxid dismutase, tyrosinase, alcohol dehydrogenase, lactate dehydrogenase, and acid phosphatase were examined in populations of sexual (Taraxacum serotinum and Pilosella echioides) and apomictic (T. officinale and P. officinarum) plant species. The heterozygosity in these populations (0.455–0.620) proved to be considerably higher than the average level characteristic of plant populations (0.058–0.185). The populations examined did not differ in the mean phenotype number , i.e., they exhibited the same diversity (3.188–3.380). The proportion of rare phenotypes h also did not differ between the sexual and apomictic species of the same genus, whereas this parameter in the Pilosella populations (0.150–0.174) was significantly higher than in the Taraxacum ones (0.093–0.114). The populations were characterized by numerous isozyme spectra (more than 11 per populations) and displayed multiple allelism (the mean allele frequency was 3.63–4.38 per locus). They exhibited a high percentage of rare (occurring at a frequency lower than 5%) spectra (35–80%). This indicates that agamic complexes, to which these populations belong, may have a more complicated genetic structure of both apomictic and sexual populations than the species that do not belong to agamic complexes.Translated from Genetika, Vol. 41, No. 2, 2005, pp. 203–215.Original Russian Text Copyright © 2005 by Kashin, Anfalov, Demochko.     

Kinetic resolution of ketoprofen ester catalyzed by lipase from a mutant of CBS 5791

A biotransformation process was developed for the production of (S)-ketoprofen by enantioseletive hydrolysis of racemic ketoprofen ester using the mutant Trichosporon laibacchii strain CBS 5791. A satisfactory result was obtained, in which the E was 82.5, with an ee of 0.94 and a conversion of 0.47 under the optimum hydrolysis conditions [E is enantiomeric ratio, E=ln[1–X(1+ee)]/ln[1–X(1–ee)]; ee is enantiomeric excess, ee=(C_S–C_R)/(C_S+C_R): temperature of hydrolysis was 23°C]. The medium used in biotransformation was a mixture of growth broth and biotransformation broth at a ratio of 1:9, the concentration of Tween 80 was 15 g/l, the time of hydrolysis, 72 h. These results are promising for further scale-up. Tween 80 significantly improved lipase enantioselectivity and activity at the optimum concentration.     

Transgenic resistance to <Emphasis Type="Italic">Cymbidium mosaic virus</Emphasis> in <Emphasis Type="Italic">Dendrobium</Emphasis> expressing the viral capsid protein gene

A Taiwan isolate of Cymbidium mosaic virus (CymMV-CS) was isolated from infected Cymbidium sinesis Willd. The cDNA of the capsid protein (CP) gene was synthesized and sequenced. Alignment of this CP gene with other reported CPs revealed homologies of 92–98% at the nucleotide level and 98–99% at the amino acid level. To generate virus-resistant varieties, the CymMV-CS CP gene was transformed into Dendrobium protocorms through particle bombardment. Transformants were selected on medium supplemented with 20 mg/L hygromycin and the presence of the transgene was confirmed by polymerase chain reaction, Southern, Northern and Western blot analyses. Transgenic Dendrobium harboring the CymMV CP gene expressed a very low level of virus accumulation four months post-inoculation with CymMV, as detected by ELISA. The transgenic plants exhibited much milder symptoms than the non-transgenic plants upon challenge with CymMV virionsSequence data reported from this article have been deposited at the GenBank Data Libraries under Accession No. AY429021.     

Antimicrobial resistance among urinary tract infection (UTI) isolates in Europe: results from the SENTRY Antimicrobial Surveillance Program 1997

The SENTRY Antimicrobial Surveillance Program was established to monitor the occurrence and antimicrobial susceptibility of bacterial pathogens via an international network of sentinel hospitals. Twenty European hospitals referred a total of 887 urinary tract infection (UTI) isolates to the European SENTRY reference laboratory during the period October–December 1997. Ninety percent of the referred species were represented by Escherichia coli (52%), Enterococcus spp. (12%), Klebsiella spp. (7%), Proteus spp. (7%), Pseudomonas aeruginosa (7%), and Enterobacter spp. (5%). The susceptibility of E. coli isolates to penicillins was less than 60%, while almost all of the isolates were susceptible to piperacillin/tazobactam (98% susceptibility), cephalosporins (98%), and carbapenems (100%). Amikacin was the best aminoglycoside (99.8% susceptibility). The susceptibility to quinolones was only 88–89%, with highest levels of resistance observed for isolates from Portugal, Italy, England, The Netherlands, and some centers in France, Spain, and Poland. The susceptibility of Klebsiella spp. to the newer generations of cephalosporins was 82–95% and to the carbapenems 100%. Amikacin was again the best aminoglycoside (94% susceptibility). The susceptibility of Enterobacter spp. to any ß-lactam antibiotic was poor, except for the carbapenems (100% susceptibility) and cefepime (90% susceptibility), while the susceptibility to aminoglycosides was 80–89%. Proteus spp. showed complete susceptibility to cefepime, ceftriaxone, the carbapenems, and piperacillin/tazobactam, while the susceptibility of P. aeruginosa isolates was poor, with best results for the carbapenems (susceptibility 89%), piperacillin/tazobactam (susceptibility 84%), and amikacin and ticarcillin (susceptibility to both 80%). Enterococcus spp. showed the highest susceptibility to vancomycin (98%), teicoplanin (98%), and ampicillin (94%).     

Enantioselective Organocatalytic Oxaziridination of N‐Tosyl Aldimine Catalyzed by Cinchona Alkaloid‐Ester Derivatives

A series of cinchona alkaloid‐ester derivatives was synthesized and applied to catalyze the enantioselective oxaziridination of aryl aldimines with m‐CPBA. The (R,R)‐oxaziridines were obtained in good yields with high enantiomeric excess (ee) values (up to 98%). Chirality 26:150–154, 2014. © 2014 Wiley Periodicals, Inc.     

A high cell density fermentation strategy to produce recombinant malarial antigen in <Emphasis Type="Italic">E. coli</Emphasis>

A high cell density cultivation method was developed to produce recombinant PvRII, a malaria vaccine candidate, in E. coli for use in vaccine studies. Cells were grown in completely defined media and glucose was fed to achieve a specific growth rate of 0.12 h^–1 until cells reached 55 g dry wt l^–1. Culture was then induced with 1 mm IPTG and cells were further grown for 4 h to reach 85 g dry wt l^–1 at 0.1 h^–1. Recombinant PvRII was purified from inclusion bodies under denaturing conditions using metal affinity chromatography which yielded 10 mg PvRII g^–1 dry wt. After refolding, PvRII was greater than 98% pure, homogeneous and functionally active in that it specifically bound Duffy positive human red cells.Revisions requested 21 September 2004; Revisions received 29 October 2004     

Production of Lactobacillus kefir cells for asymmetric synthesis of a 3,5-dihydroxycarboxylate

An efficient fedbatch process for the production of Lactobacillus kefir DSM 20587 cells was developed. An improvement in space time yield of 270% (3.7 g_DCW l^–1 day^–1) and in final enzyme activity of 440% (9.1 U/ml) was achieved on a 150 l scale by controlling the oxygen transfer rate to 7–9 mmol l^–1 h^–1. The cells exhibited good and highly stereoselective reducing activities against tert-butyl 6-chloro-3,5-dioxohexanoate. tert-Butyl (3R,5S)-6-chloro-dihydroxyhexanoate, a chiral building block for HMG-CoA reductase inhibitor synthesis, was produced with 47.5% yield and >99% ee at C₃3 and C₅5 in a simple batch biotransformation process.     

Food habits of sambar <Emphasis Type="Italic">Cervus unicolor</Emphasis> at the Horton Plains National Park,Sri Lanka

The sambar Cervus unicolor has a large population in southern Asia. In Sri Lanka, its habitat use is most common among the four cervid species. We carried out an analysis of the food habits of sambar in the Horton Plains National Park from January to November 1991 by using the quantitative fecal analysis method. Analyses of sambar feces collected at the three habitats (two grassland communities and a forest) in the Horton Plains National Park found that the sambar diet largely consisted of graminoid leaves; 45–78% in grasslands and 43–60% in the forest. The analyses also found that the proportion of graminoid leaves in early summer (52–78%) was greater than it was in winter (43–49%). In spring and summer, different varieties of graminoids were consumed by sambar, whereas dicotyledonous plants were consumed in winter. The fecal nitrogen level did not fall below the critical level of their nutrition (1.1%), indicating that sambar food quality in the Horton Plains was sufficient. A large proportion of Pennisetum spp., exotic grasses (10–39%) were found in the fecal compositions collected in the Pennisetum community. This could be because of the high biomass and high nitrogen concentration (approximately 2.4%) of Pennisetum and its low-growing nature. From the present study, we found that in order for sambar, a native ungulate, not to increase in number, the growth of exotic plants such as Pennisetum needs to be controlled.     

Comparisons of morphology and neritic distributions of <Emphasis Type="Italic">Euphausia crystallorophias</Emphasis> and <Emphasis Type="Italic">Euphausia superba</Emphasis> furcilia during autumn and winter west of the Antarctic Peninsula

Euphausia crystallorophias and E. superba larvae often overlap in distribution in Antarctic coastal regions. Here, we describe the morphology and ecology of E. crystallorophias furcilia stages F3–F6, with emphasis on characteristics that distinguish them from E. superba, based on samples collected west of the Antarctic Peninsula during autumn and winter 2001 and 2002. During autumn most E. crystallorophias occurred as F4s (53%) and F5s (35%), while E. superba occurred in all furcilia stages (F1–F6). During winter, F6 was the dominant stage (>67%) for both species. On average, body lengths of E. crystallorophias larval stages were significantly greater than those of E. superba. During autumn, densities of the two species were similar (range: 0.003–11.8 m^–3) at many on-shelf stations, with lower densities during winter. Where both species occurred, >58% of E. crystallorophias furcilia were collected between 50 and 100 m depth, while 82% of E. superba were shallower (25–50 m). Younger stages of E. crystallorophias occurred more frequently (54% of F3s) in water >100 m than older stages (11% of F6s). Thus, many larval E. crystallorophias were vertically segregated from E. superba, thereby reducing grazing competition between the young of these morphologically similar species.     

Differences in growth,total lipid content and fatty acid composition among 60 clones of <Emphasis Type="Italic">Cylindrotheca fusiformis</Emphasis>

Differences between clones of the diatom Cylindrotheca fusiformi were studied with respect to growth rate, total lipid content and fatty acid composition. Sixty clones were isolated and cultivated under batch conditions. All clones were grown under identical conditions (temperature 22±1°C, light intensity 100 μmol photon m⁻² s⁻¹, salinity 28, F/2 medium) and were harvested in the late exponential growth phase for lipid and fatty acid analysis. The results show a wide variation in growth, total lipid content and fatty acid profiles among clones (p<0.05). The major fatty acids in the 60 clones were 14:0 (4.6–9.1%), 16:0 (18.2–32.0%), 16:1n-7 (21.6–33.1%), 20:4n-6 (4.1–13.5%) and 20:5n-3 (6.2–17.2%), with the highest proportion of 20:4n-6 in clone CF13 (13.5%), and the highest proportion of 20:5n-3 in clone CF5 (17.2%). The results support the view that some microalgal fatty acid variation is not restricted to interspecific variation and external factors, but also varies from clone to clone within the same species.     

Synthesis of carotenoids by<Emphasis Type="Italic"> Rhodotorula rubra</Emphasis> GED8 co-cultured with yogurt starter cultures in whey ultrafiltrate

Two cultures, a yeast (Rhodorula rubra GED8) and a yogurt starter (Lactobacillus bulgaricus 2–11+Streptococcus thermophilus 15HA), were selected for associated growth in whey ultrafiltrate (WU) and active synthesis of carotenoids. In associated cultivation with the yogurt culture L bulgaricus 2–11+S. thermophilus 15HA under intensive aeration (1.3 l^–1min^–1 air-flow rate) in WU (45 g lactose l^–1), initial pH 5.5, 30 °C, the lactose-negative strain R. rubra GED8 synthesized large amounts of carotenoids (13.09 mg l^–1 culture fluid). The carotenoid yield was approximately two-fold higher in association with a mixed yogurt culture than in association with pure yogurt bacteria. The major carotenoid pigments comprising the total carotenoids were -carotene (50%), torulene (12.3%) and torularhodin (35.2%). Carotenoids with a high -carotene content were produced by the microbial association 36 h earlier than by Rhodotorula yeast species. No significant differences were notd in the ratio between the pigments synthesized by R. rubra GED8+L. bulgaricus 2–11, R. rubra GED8+S. thermophilus 15HA, and R.rubra GED8+yogurt culture, despite the fact that the total carotenoid concentrations were lower in the mixed cultures with pure yogurt bacteria.     

Effect of different protein–energy ratio in pulse by-products and residue based pelleted feeds on growth, rumen fermentation, carcass and sausage quality in Barbari kids

Thirty two Barbari kids (5-month old of 10.62 ± 0.09 kg BW, 16 males and 16 females) were equally divided into four groups to monitor growth, nutrient utilization, rumen fermentation, blood metabolites, carcass traits, meat and sausage quality on diet based on Cajanus cajan straw (60) and concentrate mixture (40) to have different protein–energy ratio in the diets (Diet 1—CP 12%, TDN 55%, Diet 2—CP 12%, TDN 60%, Diet 3—CP 14%, TDN 55% and Diet 4—CP 14%, TDN 60%). The experimental kids in each group were fed the respective diets at 4% of their body weight and limited quantity (300–400 g/kid/day) of oat fodder. The average DM intake/kg W^0.75 during growth period was significantly (P < 0.05) higher in Diet 1 (low protein–low energy) than Diet 4 (high protein–high energy). Kids under Diet 2 (low protein–high energy) and Diet 4 (high protein–high energy) gained 7.2% and 14.5% more weight respectively per day compared to those on Diet 1 (low protein–low energy), however, values of final body weight, average daily gain and feed conversion efficiency (%) were not significantly different (P > 0.05). The pH and total VFA concentration in the rumen liquor were similar (P > 0.05) among the four treatment groups. TCA precipitable-N was insignificantly (P > 0.05) higher in Diet 4 than other diets. Glucose, urea–nitrogen, total protein, albumin and globulin concentration in plasma were unaffected by treatments. TDN intake, DCP and TDN percentages were also similar (P > 0.05) among the four groups. Nitrogen balance (g/day/kid) values also showed no significant variation. Dietary effect was also not significant (P > 0.05) in the values of hot carcass weight, dressing percentage, carcass physical composition, variety meat yield and fat deposition but not breast fat thickness and kidney fat accumulation, which were significantly (P < 0.05) higher in Diet 2. Chemical composition values of Longissimus thoracis muscle were similar (P > 0.05) in percentage moisture, fat and ash, while CP was significantly (P < 0.05) higher in Diets 2 and 3 than Diets 1 and 4. There were no significant differences (P > 0.05) in the chemical composition of sausages prepared using meat from the kids of different treatments. Therefore, it may be concluded that pelleted feed of Diet 2 responded with better growth rate, quality of carcass traits and meat quality.     

The role of different anions in ionic liquids on Pseudomonas cepacia lipase catalyzed transesterification and hydrolysis

Lipase Pseudomonas cepacia (PS) catalyzed transesterification of ethyl 3-phenylpropanoate with eleven alcohols was investigated in three ionic liquids [ILs], [Bmim]BF₄, [Bmim]PF₆, and [Bmim]Tf₂N, consisting of an identical cation and different anions. The yields were higher in hydrophobic ILs [Bmim]Tf₂N (55–96%) and [Bmim]PF₆ (22–95%), than in hydrophilic [Bmim]BF₄ (0–19%). The incubation of lipase PS in hydrophobic ILs for a period of 20–300 days at room temperature resulted in an increased yield of 62–98% in [Bmim]Tf₂N and 45–98% in [Bmim]PF₆, respectively. The lipase PS-hydrophobic IL mixture was recycled five times without any decrease in the yield of the products. In another set of experiments, the hydrolytic activity of the enzyme was determined after incubation in each of the three ILs and in hexane for 20 days at room temperature. It was found to be 1.8- and 1.6-fold higher in [Bmim]Tf₂N and [Bmim]PF₆, respectively, remained unchanged in [Bmim]BF₄ and was 1.6 times lower in hexane as compared to the non-incubated enzyme.     

A new species of amblycipitid catfish, <Emphasis Type="Italic">Xiurenbagrus gigas</Emphasis> (Teleostei: Siluriformes), from Guangxi,China

A new species of amblycipitid catfish is described based on five specimens (88.0–164.5mm in standard length: SL) collected from the vicinity of Duan, Guangxi Zhuangzu Autonomous Region, southern China. The new species, Xiurenbagrus gigas, is different from all other known amblycipitid catfish, but similar to X. xiurenensis by having two patches of vomerine teeth. The new species can be distinguished from X. xiurenensis by having a larger head (head length: 27.9–34.9% vs. 21.8–26.4% SL; head depth: 14.4–17.9% vs. 12.4–14.1% SL; head width: 22.4–29.4% vs. 18.1–20.3% SL), lower adipose fin (4.6–6.0% vs. 6.5–8.3% SL), shorter distance from dorsal origin to adipose origin (25.7–32.0% vs. 32.9–38.9% SL), longer dorsal fin (21.2–24.9% vs. 16.2–19.1% SL), longer pectoral fin (18.4–20.7% vs. 13.5–16.8% SL), longer pelvic fin (13.1–14.3% vs. 8.8–11.8% SL), and more gill rakers (7–9 vs. 5). Xiurenbagrus gigas, the largest known species in the family Amblycipitidae, is distributed in the Xijiang River, the longest tributary of the Zhujiang (Pearl) River basin.     

Serum selenium and selenoprotein P status in adult Danes – 8-year followup

Selenium is an essential micronutrient important to human health. The main objective of this study is to describe serum selenium and selenoprotein P status in two samples of the Danish population. In addition, the influence of various factors potentially associated with selenium status was investigated.Blood samples from a total of 817 randomly selected subjects from two cities in Denmark were analyzed. Half of the samples were collected in 1997–1998 and the other half in 2004–2005. Samples from women aged 18–22, 40–45 and 60–65 years, and men aged 60–65 years were selected for this study. All subjects had filled in a food frequency questionnaire (FFQ) and a questionnaire with information about smoking habits, alcohol consumption and exercise habits.Mean serum selenium level was 98.7±19.8 μg/L and median selenoprotein P level was 2.72 (2.18–3.49) mg/L. Serum selenium and selenoprotein P increased with age, and selenoprotein P was higher in men than in women. Serum selenium levels decreased by 5% on average from 1997–98 to 2004–05 (P<0.001), whereas selenoprotein P level increased (P<0.001). The intake of fish correlated weakly with serum selenium level (r=0.14, P<0.001) but not with selenoprotein P level. Smoking status, alcohol intake, exercise habits, BMI and medicine use did not influence selenium status.It is concluded that selenium status in this Danish population is at an acceptable level. No major groups with regard to age, sex or lifestyle factors could be identified as being in risk for selenium deficiency.