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Commercial Production (commercial + production)
Selected AbstractsBioaugmentation of tar-contaminated soils under field conditions using Pleurotus ostreatus refuse from commercial mushroom production,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2003Helle Hestbjerg Abstract The influence of the white rot fungus Pleurotus ostreatus on the degradation of selected poly- and heterocyclic aromatic hydrocarbons (referred to as polycyclic aromatic hydrocarbons [PAHs]) in soil was investigated under field conditions representing the Northern temperate zone. Pleurotus ostreatus was added to two contaminated soils in the form of homogenized refuse from the commercial production of fungus. The soils were collected from a former shipyard (the B&W soil) and underneath a former coal tar storage at an old asphalt factory in Denmark (the Ringe soil). Treatments (control, soil mixed with autoclaved sawdust medium, and soil mixed with P. ostreatus refuse) were set up in triplicate in concrete cylinders (height, 50 cm; diameter, 60 cm). The activity of P. ostreatus was measured as laccase activity and phenanthrene (PHE)- and pyrene (PYR)-degrading bacteria were enumerated. Twenty-one different PAHs were quantified. After nine weeks the concentrations of the 3-, 4-, 5-, and 6-ring PAHs in the Ringe soil were reduced by 78, 41, and 4%, respectively. These reductions corresponded with high initial laccase activity, a decrease in pH caused by the fungus, and an increase in the number of PHE- and PYR-degrading bacteria. No significant PAH degradation was observed in the B&W soil. Reasons for the difference in performance of P. ostreatus in the two soils are discussed in terms of soil histories and bioavailability. The use of P. ostreatus refuse holds promising potential for bioremediation purposes. [source] Production and sensory characteristics of flavoured soymilk samplesINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 3 2003Christina Antwiwaa Nti Abstract The sensory quality characteristics of four flavoured soymilk samples including vanilla, banana, coffee and chocolate were evaluated at varying concentrations of the flavour. This was done to establish the most acceptable flavour and desired concentration for commercial production of soymilk and also to facilitate increased consumption of soymilk for improved nutrition. Hot extraction of the milk from blanched soybeans was achieved by blending in hot water and sieving through muslin cloth. Different concentration levels of the flavours being assessed, namely chocolate, coffee, vanilla and banana, were added. Consumer preference for the various samples was assessed using a nine-point hedonic scale. Addition of flavours was found to improve the sensory characteristics and consumer preference of soymilk. Colour, taste, aroma, mouthfeel and hence overall acceptability of the soymilk samples were improved significantly by the addition of vanilla, banana, coffee and chocolate flavours. The maximum concentrations of the individual flavours for optimal sensory impact were established. Based on the results, the following flavour concentrations are recommended per 100 ml of soymilk: 0.03% vanilla, 0.01% banana, 1.5% coffee and 4% chocolate. [source] Studies on the appearance of skeletal anomalies in red porgy: effect of culture intensiveness, feeding habits and nutritional quality of live preysJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2010M. S. Izquierdo Summary Despite the great interest of red porgy as a new species for Mediterranean aquaculture, its commercial production is constrained by the high incidence of skeletal deformities occurring in this species under culture conditions. Several studies have been conducted to better understand the origin of these anomalies in this species, using different system intensiveness, rotifers enrichment products or rotifers docosahexaenoic acid content. The first study showed that culture intensification increased the number of fish with an extra vertebrae, what was probably related to the different nutritional quality of live preys employed in each treatment, since water temperature, salinity and genetic background were identical for the different batches of fish studied. Total incidence of skeletal abnormalities was higher in the intensive system, particularly cranial abnormalities and kyphosis in the cephalic vertebrae. In both rearing systems the most common skeletal anomalies were vertebral column disorders, lordosis and fused vertebrae, their localization along the column being affected by the culture intensiveness. Rotifer enrichment, predominantly its docosahexaenoic acid content significantly affected deformities occurrence. A marked positive effect of rotifer docosahexaenoic acid content was found on larval survival. X-ray studies denoted elevated levels of bone abnormalities associated, in both trials, to low docosahexaenoic acid content in live preys. Among different anomalies, the presence of fused vertebrae was the most frequent deformity for both rearing trials. A 50% reduction in the number of deformed fish for each type of deformity was obtained when the larvae were fed higher docosahexaenoic acid levels, denoting the important role of this fatty acid in bone development. Further studies are needed to elucidate the importance of essential fatty acids on the development of bone deformities in fish, since the functions of these fatty acids differ among them and can lead to very different effects in fish metabolism, including bone formation. [source] RHEOLOGICAL PROPERTIES OF CRYSTALLIZED HONEY PREPARED BY A NEW TYPE OF NUCLEIJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2009YUE-WEN CHEN ABSTRACT Good spreadability is a highly desirable quality for crystallized honey used in product applications. In this study, we processed Taiwanese liquid litchi honey into crystallized honey by adding a new nuclei material, namely 0.1% (w/w) glucose powder, instead of the traditional 5,10% (w/w) natural nuclei. Rheological properties of the resulting product were determined during heating and cooling utilizing small amplitude oscillatory shear to assess spreadability. As the product was heated, it exhibited decreased consistency and improved fluidity (evidenced by decreasing storage modulus [G,] and loss modulus [G,] values) and three distinct regions within the G,curve ("softening,""crystalline plateau" and "melting"). As the product was cooled from 55 to 0C, moduli were lower than those obtained during heating, and the product did not exhibit the three G,curve regions across the temperature range. Therefore, we observed incomplete reversible crystallization and rheological properties during temperature migration. Flow properties of crystallized honey in the 0,25C temperature range could be successfully predicted using the Herschel,Bulkley model (R2 > 0.97). However, the product approached Newtonian flow behavior as temperatures neared the upper end of this range. Higher viscosity and lower yield stress were observed at temperatures below 15C. The crystallized honey developed for this study exhibited shear-thinning properties desirable in honey products intended to be spread. PRACTICAL APPLICATIONS Crystallized honey is traditionally prepared by introducing 5,10% natural nuclei into liquid honey. Our lab developed a new method that replaces the natural nuclei with glucose powder, which, at 0.1% (w/w), produces a good quality creamed honey that, in commercial production, offers the potential for significant production cost advantages. As crystallized honey is used in commercial/consumer applications as a spread, its dynamic rheology is of both academic and industrial interest. In this study, we discuss the physical properties of the crystallized honey developed using glucose powder to help better identify the factors and variables involved in honey spreadability and thus facilitate the development of better honey products with more desirable spreadability profiles. This study also provides a rheological properties and spreadability database for crystallized honey that reflects the range of temperature changes that can be expected to occur during normal product storage and use. [source] SUPERCRITICAL FLUID EXTRACTION AND DETERMINATION OF LUTEIN IN HETEROTROPHICALLY CULTIVATED CHLORELLA PYRENOIDOSAJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2007ZHENGYUN WU ABSTRACT Chlorella is a promising alternative resource of lutein, as it can be cultivated heterotrophically and efficiently in a fermentor. In this study, high density of Chlorella pyrenoidosa was achieved by fed-batch cultivations. Lutein in Chlorella was extracted by supercritical fluid and was determined by high-performance liquid chromatography and liquid chromatography-mass spectrometry. The extraction degree of lutein reached 87.0% after 4-h extraction under the optimized conditions of 50C, 25 MPa and modified CO2 with 50% ethanol. High purity of lutein could be obtained by supercritical fluid extraction with appropriate operation parameters. The whole process developed in this study may be useful for the commercial production of lutein. [source] 71 Proteomics of haematococcus pluvialis: new opportunities for study of genomics of a non-sequenced speciesJOURNAL OF PHYCOLOGY, Issue 2003Q. Hu The green alga, Haematococcus pluvialis, has become a model organism for commercial production of the high-value carotenoid astaxanthin. H. Pluvialis has also drawn significant scientific attention because fundamental biological questions relating to the massive cellular accumulation of astaxanthin have to be addressed in order to improve the yield and quality of the algal biomass. However, research has been impeded by the lack of molecular background information on this non-sequenced species. A combination of classical biochemistry with a state-of-the-art proteomic approach was used to address these questions. This was possible by taking advantage of information already available for homologous genes/gene-products in organisms whose genomes have been sequenced. The approach involved isolation of subsets of the proteome from subcellular compartments/organelles of an organism by one- or two-dimensional electrophoresis (1-DE or 2-DE) and their identification by N-terminal sequencing and peptide mass fingerprinting (PMF), involving matrix-assisted laser desorption/ionization and time-of-flight (MALDI-TOF) mass spectrometry coupled with bioinformatics. Based upon the information obtained from the combined methods, expression and physiological functions of specific genes/encoded proteins may be deduced. Examples include profiling of cell wall proteins, biogenesis and protein composition of lipid bodies, and expression patterns of soluble proteins under stress conditions. Advantages and limitations of the method for non-sequenced organisms and for cross-species protein identification will also be discussed. [source] RT-PCR Detection of Odontoglossum ringspot virus, Cymbidium mosaic virus and Tospoviruses and Association of Infections with Leaf-Yellowing Symptoms in PhalaenopsisJOURNAL OF PHYTOPATHOLOGY, Issue 5 2008K. Yamane Abstract Leaf-yellowing symptoms in Phalaenopsis are most important effects in its commercial production in Japan and their cause has not yet been clarified. In the present study, Odontoglossum ringspot virus (ORSV), Cymbidium mosaic virus (CymMV) and tospoviruses were evaluated by reverse transcription-polymerase chain reaction (RT-PCR) in Phalaenopsis showing leaf-yellowing symptoms. Ring, spot, mosaic, necrosis and other symptom types were observed in 42%, 24%, 25%, 16% and 44% of the tested plants respectively. ORSV was detected in 55% of the plants, particularly in 35 of 42 plants with ring symptoms. CymMV was detected in 34% of the plants, particularly in 18 of 25 plants with mosaic symptoms. Plants co-infected with both viruses tended to show severe symptoms. In spite of systemic infection by inoculation of ORSV, no clear ring symptoms were observed in any plant for 6 months. Symptoms of leaf-yellowing were significantly reduced after 3 months. These results suggest that the symptoms can be associated with the viruses but occurred and alleviated over time and by changes in the environmental conditions. No tospoviruses were detected in 70 tested plants. ORSV and CymMV were simultaneously detected by RT-PCR using reported primers for ORSV and newly designed primers for CymMV using an efficient direct tube RNA extraction technique providing more cost-effective RT-PCR screening. No viruses were detected by RT-PCR in several plants showing spot or ring symptoms, suggesting the presence of other causal agents related to these symptoms. [source] COMPARISON OF INSTRUMENTAL METHODS FOR MEASURING SEED HARDNESS OF FOOD-GRADE SOYBEANJOURNAL OF TEXTURE STUDIES, Issue 1 2008BO ZHANG ABSTRACT Breeding specialty soybeans for the soyfood market requires proper methodology in evaluation of seed quality attributes. In this study, efficient methods that could be potentially used for testing soybean seed hardness were developed by examining different instruments and seed parameters. Five food-grade soybean genotypes with different seed sizes were used to determine seed water-absorption capacity and hardness. Water absorption capacity was expressed by swell ratios for seed weight, seed dimension, and volume of water changes before and after soaking. Seed hardness test was conducted by a one-bite method using a food texture analyzer equipped with five different probes. The results showed that hardness testing by a 75 mm cylinder with 10 steamed seeds, single blade with five steamed seeds, and shear cell with 30 g steamed seeds produced dependable and consistent results with low coefficient of variance. However, shear cell may not be practical for early plant selection in a breeding program due to a relatively large sample requirement. Seed size can be used as indirect selection indicators for seed hardness. PRACTICAL APPLICATIONS Seed hardness is an important factor in determining soybean suitability for natto production. This study used two texture analyzers equipped with five different probes to test hardness of five soybean genotypes with different seed size. The methodologies for testing the seed texture of soybean have been established, which can help regulate the seed hardness testing for commercial production and provide consistent hardness references for natto breeding programs and the seed industry. [source] Effects of cassava processing methods on antinutritional components and health status of children,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2002Omorogieva Ojo Abstract This study was conducted to evaluate cassava processing methods in Nigeria, its antinutritional components and the possible impact on the health status of children. The traditional method of cassava processing involved peeling of cassava tubers with a knife, manual grating, dewatering with logs of wood and/or stones, sieving with a cane-woven sieve and frying in a local metal fryer on a wood fire. In contrast, the modern method involved the use of knives for peeling, a mechanical grater, a hydraulic press for dewatering, iron sieves for sieving and an improved metal fryer for frying on a coal fire. The products of both methods included gari (accounting for 70% of Nigeria's total cassava consumption) and lafun. The intake of gari and other foods in 129 3,5-year-old children in Benin City, Nigeria was also assessed based on a food frequency questionnaire. The children were classified into normal and protein-deficient groups using lower/middle/upper-arm circumference and clinical features of malnutrition. Based on the number of households in villages around Benin City who were involved in cassava processing, 90% used the traditional processing method compared with 10% using the modern method, although the latter controlled the commercial production and sale of gari. There were significantly (P,<,0.05) higher intakes of protein and energy in normal compared with protein-deficient children, but the latter group obtained higher percentages of protein and energy from gari. In addition, the correlation between the amount of gari consumed and clinical scores of malnutrition was low (R2,<,0.2). This may be due to the children consuming gari from both methods and also from different sources. The average gari intake for these children was 320,g,day,1 and HCN levels may be as high as 10.24,mg,day,1. Some children who are exposed to these levels with poor nutritional status and lack of access to food varieties may develop sublethal effects in the short term. The higher protein intake by the normal children may also reduce the toxicity of HCN. We conclude that methods of processing cassava have profound effects on HCN retention and chemical composition of cassava products. In addition, the modern processing method is more efficient than the traditional method, with significantly reduced processing losses, labour input and levels of HCN. The HCN content in combination with the quantity and quality of protein in the diet has significant impact on the health status of children. Therefore, in susceptible children with poor nutritional status who consume inadequately processed cassava products with limited food choice, these may predispose them to the effects of HCN and thiocyanate. © 2002 Society of Chemical Industry [source] The Effects of Temperature and Salinity on Early Life Stages of Black Sea Bass Centropristis striataJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2004David L. Berlinsky Along the Atlantic coast black sea bass occur from the Gulf of Maine to Florida and support important commercial and recreational fisheries. Interest in commercial production of black sea bass has increased in recent years due to high demand and limited seasonable availability. Efforts towards large-scale production have been hampered by a high incidence of early larval mortality. Two of the most important environmental variables affecting hatchery production of marine finfish larvae are temperature and salinity. In the wild, larval black sea bass are found in waters with temperatures of 12,24 C and salinity levels of 30,35 ppt. Studies were conducted to define the temperature and salinity ranges that support growth and development of black sea bass during early life stages. Three developmental phases were investigated: 1) fertilization to hatch: 2) hatch through yolk sac absorption: and 3) during the initial exogenous feeding stage (5,14 days post hatch: DPH). Fertilized eggs were obtained by manual spawning of fish following administration of LHRHa. Fertilized eggs were transferred to 300-mL glass Petri dishes or 500-mL beakers to assess the effects of salinity and temperature through hatch and yolk sac absorption, respectively. To determine environmental effects on growth and survival during initial exogenous feeding 400 actively feeding larvae were cultured in green water and fed enriched rotifers for a 9-d period. For investigation of the effect of salinity, sea water (35 ppt) was diluted gradually to 15, 20, 25, and 30 ppt and maintained at 21 C. For examination of the effect of temperature, seawater was adjusted from 21 C to 12, 15, 21, 27, or 30 C at a rate of 3 C/h. No eggs hatched at 12 C or when salinity was maintained at 0 or 5 ppt. Hatching was uniformly high (, 85%) at temperatures between 15 and 27 C and at salinities , 15 ppt. Survival through yolk sac absorption was greatest at temperatures between 18 and 27 C and at salinities , 20 ppt. Survival through first feeding stage was highest at temperatures , 18 C and 30 ppt salinity. Larval growth through first feeding was not significantly affected by salinity level but did increase with rearing temperature. The results indicate that survival and development of black sea bass during early life stages are most favorable at temperatures >18 C with salinity levels approaching full strength seawater. [source] Sustained, Natural Spawning of Southern Flounder Paralichthys lethostigma Under an Extended Photothermal RegimeJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2001Wade O. Watanabe Hormone-induced spawning of southern flounder Paralichthys lethostigma has produced substantial numbers of viable eggs, but wide variations in fertilization and hatch rates have been reported. Recently, sustained natural spawning of southern flounder broodstock, without hormone induction, has been achieved in our laboratory. Adults (average weight = 1.12 kg; N= 25), including 6 captured as juveniles in 1993 and 19 captured as adults during September 1998, were stocked in two 4.8-m3 controlled-environment tanks in October 1998 and held under natural photothermal conditions until January 1999, when an artificial winter photo-period of 10 L:14 D was initiated and then maintained through April 1999. Sex ratio was approximately 13 females:8 males:7 unknown. Natural spawning was observed in early December 1998 and increased in frequency to a peak in March 1999, before declining in late April. Water temperature ranged from 13.9 to 24.5 C during the spawning period. Natural spawnings over 142 d produced a total of 18.3 × 106 eggs, with a mean fertilization rate of 28.0% (range = 0,100%), yielding 4.94 × 106 fertilized eggs. The mean percentage of eggs that remained buoyant in full-strength seawater (34 ppt) was 41.3% (0,98%), while hatching rate of buoyant eggs was 37.3% (0,99%) and survival of yolksac larvae to the first-feeding stage was 30.2% (0,100%). Gonadal biopsies in late April identified six females from both tanks as probable spawners. A preliminary comparison suggests that natural spawning produced much larger numbers of viable eggs per female, with higher egg quality (i.e., fertilization and hatching success) than hormone-induced spawning. In contrast to natural spawning, hormone-induced strip-spawning enabled timing of spawnings to be more precisely controlled. These results suggest that a combination of both natural and hormone-induced spawning of photothermally conditioned fish will help produce the large numbers of eggs required to support commercial production. [source] Kinetic modeling of lutein production by heterotrophic Chlorella at various pH and temperaturesMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 8 2006Xianming Shi Abstract Kinetics of lutein production by heterotrophic Chlorella protothecoides was investigated with respect to pH and temperature. Flask cultures with initial pH 5.0,8.0 were carried out, and it was found that pH 6.0 was optimal for the algal growth. Further tests in fermentors showed that the highest biomass concentration, maximum cellular lutein content and lutein yield were achieved at pH 6. 6. In addition, it was shown that optimal biomass concentration and lutein yield were obtained at 28°C, while application of 35°C resulted in the highest cellular lutein content. A mathematical model was developed for the description of the processes under these cultivation conditions and the kinetic model fitted well to the experimental data. The obtained results may contribute to the commercial production of lutein by C. protothecoides. [source] Remnants of the Waikato: Native forest survival in a production landscapeNEW ZEALAND GEOGRAPHER, Issue 1 2005Mairi Jay Abstract:, This paper addresses the issue of conservation of native biodiversity on privately owned farmland in New Zealand. Based on surveys of Waikato dairy farmers as exemplars of intensive agricultural practice, it examines factors that influence the survival of native forest on land with potential for commercial production. Results suggest that a significant proportion of Waikato dairy farmers regard native forest favourably, although the proportion of farmers who actively conserve their forest is small. Factors that assist the persistence of native forest on dairy farms include personal characteristics of the farmer, past accidents of history which have left forest remnants in place, and physical characteristics of the farm such as topography. While the conservation of native biodiversity within this intensively farmed landscape is strongly influenced by political economy pressures that encourage production, non-utilitarian motives such as aesthetic enjoyment and family heritage can serve to counter the production ethic. [source] Genetic diversity among parental lines of Indica hybrid rice (Oryza sativa L.) in China based on coefficient of parentagePLANT BREEDING, Issue 6 2006S. Wang Abstract Genetic diversity constitutes the raw material for plant improvement, and provides protection against genetic vulnerability to biotic and abiotic stresses. Diversity of parental lines of indica hybrid rice in China is not well-characterized. The major objective of this study was to quantify genetic diversity of Chinese parental lines of hybrid rice via coefficient of parentage (COP). All 100 parental lines of hybrid rice widely used in hybrid breeding and commercial production during 1976,2003 were studied by COP analysis. The mean COP for the 100 parental lines was low (0.056), indicating a potentially high degree of diversity in Chinese hybrid rice breeding. Forty-nine percent of all pairs of parental lines were completely unrelated by pedigree data. The low mean COP for the parental lines was attributed to a continual incorporation of exotic germplasm (wild rice, japonica and javanica etc.) into the genetic base over time, to the introduction of foreign germplasm from the Philippines (International Rice Research Institute), Korea, the United States, Thailand, and Guyana as breeding stock. The mean COP from 1976 to 1990 was twice as much as that from 1990 to 2003. Cluster analysis was an effective method to discriminate diversity, ten clusters were identified, and maintainer lines, restorer lines and other parental lines with special genetic background were clearly grouped. In addition, restorer lines were further divided into 11 sub-clusters, which basically was in agreement with hybrid rice breeding. Among ten provinces, Hunan, Sichuan and Fujian were outstanding for breeding 54 of 100 parental lines in hybrid rice production, and the genetic diversity of parental lines in Fujian, Sichuan,Guangxi, Hunan and Jiangsu were all narrower than that in Hubei, Guangdong, Zhejiang and Jiangxi. The result of coefficient of parentage analysis for 100 parental lines may promote the management of parental diversity and hybrid rice breeding in China. [source] Heterosis for yield and other agronomic traits of winter triticale F1 and F2 hybridsPLANT BREEDING, Issue 4 2001G. Oettler Abstract Triticale is generally treated as a self-pollinating crop and line breeding is practised. Hybrid breeding has been discussed for some time, but there is little information for winter triticale. This study investigated heterosis for eight agronomic traits in F1 and F2 hybrids grown together with their parents as drilled plots in three environments. On average, grain yield heterosis was 12.5 dt/ha (a relative 10.5%) compared with the mid-parent value for F1 hybrids, and 6.2 dt/ha (5.0%) for F2 hybrids and withawide range of 4.4,17.1 dt/ha for F1 hybrids. A positive contribution to the heterosis of yield was made by kernels/spike and 1000-kernel weight, whereas spikes/m2 showed negative heterosis. Hybrid plants in F1 and F2 were taller than mid-parents (8.3 cm and 5.3 cm, respectively), with a tendency to earlier heading. The negative heterosis for falling number in F1 and F2 hybrids could be a problem for commercial production of triticale hybrids. By selecting parents for combining ability and the identification of heterotic patterns, grain yield heterosis of 20% appears feasible. [source] Effect of Pepino mosaic virus on the yield and quality of glasshouse-grown tomatoes in the UKPLANT PATHOLOGY, Issue 5 2006N. J. Spence Two fully replicated trials were conducted with glasshouse-grown tomatoes, under conditions similar to commercial production, to define the impact of Pepino mosaic virus (PepMV). PepMV was not found to reduce bulk yields in these trials, but the quality of tomato fruits harvested was reduced significantly. Compared with uninoculated, PepMV-free control plants, 6·5% of fruits of PepMV-affected cv. Espero were downgraded from class 1 in trial 1. In trial 2, an average 38% of class 1 fruits from PepMV-affected cvs Espero and Encore were lost as a result of downgrading. Loss of quality was mainly a result of blotchy ripening, gold marbling, gold spot, and symptoms directly attributed to PepMV infection. PepMV infection also affected fruit size. The results are discussed in relation to the demands of multiple retailers in the UK for class 1 tomatoes only. [source] Mechanical properties of injection molded long fiber polypropylene composites, Part 1: Tensile and flexural propertiesPOLYMER COMPOSITES, Issue 2 2007K. Senthil Kumar Innovative polymers and composites are broadening the range of applications and commercial production of thermoplastics. Long fiber-reinforced thermoplastics have received much attention due to their processability by conventional technologies. This study describes the development of long fiber reinforced polypropylene (LFPP) composites and the effect of fiber length and compatibilizer content on their mechanical properties. LFPP pellets of different sizes were prepared by extrusion process using a specially designed radial impregnation die and these pellets were injection molded to develop LFPP composites. Maleic-anhydride grafted polypropylene (MA- g -PP) was chosen as a compatibilizer and its content was optimized by determining the interfacial properties through fiber pullout test. Critical fiber length was calculated using interfacial shear strength. Fiber length distributions were analyzed using profile projector and image analyzer software system. Fiber aspect ratio of more than 100 was achieved after injection molding. The results of the tensile and flexural properties of injection molded long glass fiber reinforced polypropylene with a glass fiber volume fraction of 0.18 are presented. It was found that the differences in pellet sizes improve the mechanical properties by 3,8%. Efforts are made to theoretically predict the tensile strength and modulus using the Kelly-Tyson and Halpin-Tsai model, respectively. POLYM. COMPOS., 28:259,266, 2007. © 2007 Society of Plastic Engineers [source] Microstructure-thermal property relationship of high trans -1,4-poly(butadiene) produced by anionic polymerization of 1,3-butadiene using an initiator composed of alkyl aluminum, n -butyl lithium, and barium alkoxidePOLYMER ENGINEERING & SCIENCE, Issue 1 2009Juan J. Benvenuta-Tapia This article deals with the characterization of high trans -1,4-poly(butadiene) (TPBD) prepared by means of an anionic polymerization using an initiator composed of alkyl aluminum, n -butyl lithium, and barium alkoxide. By controlling both initiator composition and polymerization temperature, a set of TPBD was prepared with well-known number of 1,4-trans units, molecular weight distribution, and average molecular weight. Analyses by differential scanning calorimetry and diffraction of wide-angle X-rays showed a direct relationship between the microstructure of the polymer and its thermal properties. By increasing the number of 1,4-trans units (70,90%), the crystallinity of the polymer was increased (10,30%); polymers with less than 65% of 1,4-trans units were amorphous, whereas TPBD with a number of 1,4-trans units greater than 80% were polymorphous and presented two endothermic transitions. Summing up, the results presented in this article indicate that cyclohexane solutions of alkyl aluminum, n -butyl lithium, and barium alkoxide allow produce polybutadienes with enough amount of 1,4-trans units to display a regular microstructure that makes them susceptible to experience-induced crystallization, likewise at a reaction rate similar to that observed for the commercial production of poly(butadiene) with n -butyl lithium. POLYM. ENG. SCI., 2009. © 2008 Society of Plastics Engineers [source] Structural-based mutational analysis of d -aminoacylase from Alcaligenes faecalis DA1PROTEIN SCIENCE, Issue 11 2002Cheng-Sheng Hsu Abstract d -Aminoacylase is an attractive candidate for commercial production of d -amino acids through its catalysis in the zinc-assistant hydrolysis of N -acyl- d -amino acids. We report here the cloning, expression, and structural-based mutation of the d -aminoacylase from Alcaligenes faecalis DA1. A 1,007-bp PCR product amplified with degenerate primers, was used to isolate a 4-kb genomic fragment, encoding a 484-residue d -aminoacylase. The enzyme amino-terminal segment shared significant homology within a variety of enzymes including urease. The structural fold was predicted by 3D-PSSM to be similar to urease and dihydroorotase, which have grouped into a novel ,/,-barrel amidohydrolase superfamily with a virtually indistinguishable binuclear metal centers containing six ligands, four histidines, one aspartate, and one carboxylated lysine. Three histidines, His-67, His-69, and His-250, putative metal ligands in d -aminoacylase, have been mutated previously, the remaining histidine (His-220) and aspartate (Asp-366) Asp-65, and four cysteines were then characterized. Substitution of Asp-65, Cys-96, His-220, and Asp-366 with alanine abolished the enzyme activity. The H220A mutant bound approximately half the normal complement of zinc ion as did H250N. However, the C96A mutant showed little zinc-binding ability, revealing that Cys-96 may replace the carboxylated lysine to serve as a bridging ligand. According to the urease structure, the conserved amino-terminal segment including Asp-65 may be responsible for structural stabilization. [source] Structure-based prediction of modifications in glutarylamidase to allow single-step enzymatic production of 7-aminocephalosporanic acid from cephalosporin CPROTEIN SCIENCE, Issue 1 2002Karin Fritz-Wolf Abstract Glutarylamidase is an important enzyme employed in the commercial production of 7-aminocephalosporanic acid, a starting compound in the synthesis of cephalosporin antibiotics. 7-aminocephalosporanic acid is obtained from cephalosporin C, a natural antibiotic, either chemically or by a two-step enzymatic process utilizing the enzymes D-amino acid oxidase and glutarylamidase. We have investigated possibilities for redesigning glutarylamidase for the production of 7-aminocephalosporanic acid from cephalosporin C in a single enzymatic step. These studies are based on the structures of glutarylamidase, which we have solved with bound phosphate and ethylene glycol to 2.5 Å resolution and with bound glycerol to 2.4 Å. The phosphate binds near the catalytic serine in a way that mimics the hemiacetal that develops during catalysis, while the glycerol occupies the side-chain binding pocket. Our structures show that the enzyme is not only structurally similar to penicillin G acylase but also employs essentially the same mechanism in which the ,-amino group of the catalytic serine acts as a base. A subtle difference is the presence of two catalytic dyads, His B23/Glu B455 and His B23/Ser B1, that are not seen in penicillin G acylase. In contrast to classical serine proteases, the central histidine of these dyads interacts indirectly with the O, through a hydrogen bond relay network involving the ,-amino group of the serine and a bound water molecule. A plausible model of the enzyme,substrate complex is proposed that leads to the prediction of mutants of glutarylamidase that should enable the enzyme to deacylate cephalosporin C into 7-aminocephalosporanic acid. [source] Isolation of Y- and X-linked SCAR markers in yellow catfish and application in the production of all-male populationsANIMAL GENETICS, Issue 6 2009D. Wang Summary Sex controls have been performed in some farmed fish species because of significant growth differences between females and males. In yellow catfish (Pelteobagrus fulvidraco), adult males are three times larger than female adults. In this study, six Y- and X-linked amplified fragment length polymorphism fragments were screened by sex-genotype pool bulked segregant analysis and individual screening. Interestingly, sequence analysis identified two pairs of allelic genes, Pf33 and Pf62. Furthermore, the cloned flanking sequences revealed several Y- and X-specific polymorphisms, and four Y-linked or X-linked sequence characterized amplified region (SCAR) primer pairs were designed and converted into Y- and X-linked SCAR markers. Consequently, these markers were successfully used to identify genetic sex and YY super-males, and applied to all-male population production. Thus, we developed a novel and simple technique to help commercial production of YY super-males and all-male populations in the yellow catfish. [source] Growth, salinity tolerance and microsatellite analysis of the F2 reciprocal hybrids of Oreochromis niloticus×Sarotherodon galilaeus at different salinitiesAQUACULTURE RESEARCH, Issue 9 2010Biao Yan Abstract Oreochromisniloticus (O), the sixth generation of Genetic Improvement of Farmed Tilapia, shows rapid growth but poor salt tolerance, while Sarotherodon galilaeus (S) exhibits opposite traits. To combine the traits, F1 progeny was obtained through artificial fertilization. Fertile F1 produced F2 by natural spawning. The mean survival times, the median survival time (ST50) or the survival rate of hybrids was greater than O. niloticus in a gradual or an acute salinity change. Plasma osmolarity, [Na+] and [Cl,] of the hybrids fluctuated in 32 g L,1 water during a 24-h period, but eventually reached levels similar to fish in freshwater. O. niloticus,×S. galilaeus, (OS F2) or S. galilaeus,×O. niloticus, (SO F2) showed the fastest growth at 22.5 g L,1, equal to about 78.2% or 69.7% of O. niloticus at 0 and 3.87 or 3.45 times that of S. galilaeus at their individual optimum growth. Growth in OS F2 was 12% faster than SO F2. Microsatellite analysis showed that F2 had more alleles, a higher polymorphism information content and greater observed and expected heterozygosity than O. or S. Population differentiation was not detected between F1 and F2. All the results indicated that F2 could be exploited for commercial production under saline conditions. [source] Advances in rearing techniques of Pagrus pagrus, (Linnaeus, 1758): comparison between intensive and semi-intensive larval rearing systemsAQUACULTURE RESEARCH, Issue 3 2010Francisco Javier Roo Abstract Red porgy, Pagrus pagrus L., is a potential candidate for marine finfish diversification on commercial Mediterranean and Atlantic coastal aquaculture. This paper described the development of a suitable larval rearing protocol for commercial application. Red porgy eggs were reared under Intensive and Semi-intensive systems until 50 days after hatching. In addition, two different weaning protocols were tested for each rearing system. The effects of these treatments were evaluated on the growth, survival and whole-body biochemical and fatty acid composition of red porgy larvae. Significant differences in growth but not in survival at 50 days after hatching were detected in trial A for the semi-intensive and intensive rearing system (23.5 ± 2.7,18.9 ± 3.4 mm; 4.4,4.9%); however, modifications in initial prey density and illumination conditions, implemented in trials B (29.5 ± 3.0,25.2 ± 1.9 mm; 21.8,5.3%) and C (26.2 ± 2.6,24.6 ± 2.6 mm; 22.7,3.8%), significantly improved survival and growth rates in the semi-intensive rearing system. Furthermore, the results in trial C confirmed the feasibility of a partial reduction in Artemia use and the significant improvement in survival rates with the new weaning protocol applied (26.4 ± 2.3,24.1 ± 3.9 mm; 28.7,12.5%) in the intensive systems. The results of this study concluded that the best larval rearing protocol for commercial production of red porgy fingerlings should include the use of semi-intensive systems. [source] Use of neuroactive catecholamines to chemically induce metamorphosis of hatchery-reared flat oyster, Ostrea angasi, larvaeAQUACULTURE RESEARCH, Issue 14 2009Stephan O'Connor Abstract Low numbers and unreliable wild catch of the native flat oyster, Ostrea angasi, spat has resulted in the NSW flat oyster industry being reliant on hatchery-produced spat. The need to produce culchless spat in the hatchery stimulated investigation of several catecholamines to induce metamorphosis in O. angasi larvae. Larvae were treated with one of four neuroactive catecholamines (epinephrine, epinephrine bitartrate, l -Dopa and GABA) at one of four concentrations (10,3, 10,4, 10,5 or 10,6 m) for one of three treatment durations (0.5, 1,2 h) to determine morphogenic action for culchless spat production. Epinephrine bitartrate at 10,3 and 10,4 m and epinephrine at 10,3, 10,4 and 10,5 m, for a treatment duration of 1,2 h, produced significantly greater numbers of spat and culchless spat, compared with any other treatment combination. The other catecholamines tested did not induce a significant increase in the total number of spat or culchless spat, over untreated controls. Separate trials found that long-term treatment (24 h) with epinephrine bitartrate and epinephrine at morphogenic concentrations inhibited metamorphosis. Consecutive daily use of epinephrine bitartrate increased the numbers of spat and culchless spat produced, but did not affect larval or short-term post-larval survival. Treatment with 10,3 m epinephrine bitartrate or 10,4 m epinephrine for 1 h is recommended for routine commercial production of culchless flat oyster spat. [source] Genetic differences in growth among wild populations of the yabby, Cherax destructor (Clark)AQUACULTURE RESEARCH, Issue 12 2002D R Jerry Abstract Before commencing a breeding programme on a new aquaculture species, it is prudent to identify populations or strains with superior characteristics for commercial production. Information on the comparative performance of populations allows informed decisions to be made on the starting genetic base for the programme. As a precursor to a breeding programme in the decapod species, Cherax destructor (Clark), five geographically isolated populations were evaluated for the traits weight at age, abdomen length and abdomen width over a period of 9 months. Mean weight at age was found to vary among the populations by up to 42%, whereas mean abdomen length was similar among four out of the five populations. No differences were found in abdomen width. This study emphasizes that rapid genetic gains can be made simply by starting a breeding programme based on faster growing populations. [source] Weaning Chinese perch Siniperca chuatsi (Basilewsky) onto artificial diets based upon its specific sensory modality in feedingAQUACULTURE RESEARCH, Issue 2001X F Liang Abstract Chinese perch are one of the most valuable food fish in China, but the sole source of feed for intensive culture is live prey fish. Our previous studies on systematic sensory physiology revealed that this species have a mechanism for this peculiar feeding habit. In the present study, a specific training procedure was designed, and both experimental (initial body weight 171.0 g; 120 days) and commercial (initial body weight 52.4 g; 240 days) net-cage cultures were conducted to investigate the training success, growth performance and survival of the trained yearlings fed with nonlive or Oregon-type moist diet. The training successes of minced prey fish and the Oregon moist diet were 100 and 89.9%, respectively, in experimental culture, and 92.2 and 83.5% in commercial culture. In an experimental trial, the fish fed minced prey fish or the Oregon moist diet attained final body weights of 472.7 g or 344.7 g, although the specific growth rates of these groups were significantly lower than that of the fish fed live prey fish (final body weight 560.0 g). Mortality was not significantly related to dietary treatment. In commercial culture, the final body weights were as follows: 750 g on live prey fish, 705 g on minced prey fish and 651 g on the Oregon moist diet. Feed costs to produce 1 kg fish were estimated to be US$6.59 for live prey fish, US$1.76 for minced prey fish and US$2.07 for the Oregon moist diet. The results of the present study confirmed that sensory modality and associative learning appear to be critical factors in determining food discrimination of Chinese perch, indicating that both minced trash fish and Oregon-type moist diet can be substituted for live prey fish in intensive commercial production. [source] Commercializing lignocellulosic bioethanol: technology bottlenecks and possible remediesBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 1 2010Saumita Banerjee Abstract With diminishing oil supplies and growing political instability in oil-producing nations, the world is facing a major energy threat which needs to be solved by virtue of alternative energy sources. Bioethanol has received considerable attention in the transportation sector because of its utility as an octane booster, fuel additive, and even as neat fuel. Brazil and the USA have been producing ethanol on a large scale from sugarcane and corn, respectively. However, due to their primary utility as food and feed, these crops cannot meet the global demand for ethanol production as an alternative transportation fuel. Lignocellulosic biomass is projected as a virtually eternal raw material for fuel ethanol production. The main bottleneck so far has been the technology concerns, which do not support cost-effective and competitive production of lignocellulosic bioethanol. This review sheds light on some of the practical approaches that can be adopted to make the production of lignocellulosic bioethanol economically attractive. These include the use of cheaper substrates, cost-effective pre-treatment techniques, overproducing and recombinant strains for maximized ethanol tolerance and yields, improved recovery processes, efficient bioprocess integration, economic exploitation of side products, and energy and waste minimization. An integrated and dedicated approach can help in realizing large-scale commercial production of lignocellulosic bioethanol, and can contribute toward a cleaner and more energy efficient world. Copyright © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] Use of Glycol Ethers for Selective Release of Periplasmic Proteins from Gram-Negative BacteriaBIOTECHNOLOGY PROGRESS, Issue 5 2007Jeffrey R. Allen Genetic modification of Gram-negative bacteria to express a desired protein within the cellapos;s periplasmic space, located between the inner cytoplasmic membrane and the outer cell wall, can offer an attractive strategy for commercial production of therapeutic proteins and industrial enzymes. In certain applications, the product expression rate is high, and the ability to isolate the product from the cell mass is greatly enhanced because of the productapos;s compartmentalized location within the cell. Protein release methods that increase the permeability of the outer cell wall for primary recovery, but avoid rupturing the inner cell membrane, reduce contamination of the recovered product with other host cell components and simplify final purification. This article reports representative data for a new release method employing glycol ether solvents. The example involves the use of 2-butoxyethanol (commonly called ethylene glycol n -butyl ether or EB) for selective release of a proprietary biopharmaceutical protein produced in the periplasmic space of Pseudomonas fluorescens. In this example, glycol ether treatment yielded ,65% primary recovery with ,80% purity on a protein-only basis. Compared with other methods including heat treatment, osmotic shock, and the use of surfactants, the glycol ether treatment yielded significantly reduced concentrations of other host cell proteins, lipopolysaccharide endotoxin, and DNA in the recovered protein solution. The use of glycol ethers also allowed exploitation of temperature-change-induced phase splitting behavior to concentrate the desired product. Heating the aqueous EB extract solution to 55 °C formed two liquid phases: a glycol ether-rich phase and an aqueous product phase containing the great majority of the product protein. This phase-splitting step yielded an approximate 10-fold reduction in the volume of the initial product solution and a corresponding increase in the productapos;s concentration. [source] Advances of amorphous wire magnetics over 27 yearsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 4 2009Kaneo Mohri Abstract An overview of advances of the amorphous wire magnetics over the past 27 years with discoveries of extremely sensitive magnetic effects such as the large Barkhausen effect, the Matteucci effect and the magnetoimpedance effect and their successive applications to security sensor tags, pen-inputting computer tablets and electronic compasses for mobile phones in commercial productions is presented. An important new topic of biocell magnetic field sensing in vitro and human physiological magnetic field sensing in vivo using a 10 pT amorphous wire magnetoimpedance sensor is also shown that would be improved using thinner glass-covered amorphous wires. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||||||||||||||