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Full-Text Articles in Life Sciences

Fatty Acid Composition Of Oil From Adapted Elite Corn Breeding Materials, Francie G. Dunlap, Pamela J. White, Linda M. Pollak, Thomas J. Brumm Sep 1995

Fatty Acid Composition Of Oil From Adapted Elite Corn Breeding Materials, Francie G. Dunlap, Pamela J. White, Linda M. Pollak, Thomas J. Brumm

Food Science and Human Nutrition Publications

The fatty acid composition of corn oil can be altered to meet consumer demands for “healthful” fats (i.e., lower saturates and higher monounsaturates). To this end, a survey of 418 corn hybrids and 98 corn inbreds grown in Iowa was done to determine the fatty acid composition of readily-available, adapted, elite corn breeding materials. These materials are those used in commercial hybrid production. Eighty-seven hybrids grown in France (18 of which also were grown in lowa) were analyzed to determine environmental influence on fatty acid content. The parents of the hybrids and the inbreds were classified in one of ...


A Three-Year Level Study Of The Profitability Of Corn And Soybean Production, Todd D. Davis, William M. Edwards Aug 1995

A Three-Year Level Study Of The Profitability Of Corn And Soybean Production, Todd D. Davis, William M. Edwards

Economic Staff Paper Series

Crop producers face many decisions each year about the quantity and quality of inputs to use, the purchasing of these inputs, and the timing of production operations. Because their time for gathering and analyzing information on which to base management decisions is limited, they need to know which decision, areas have the greatest impact on profitability. A set of detailed and accurate records of production, costs, and returns from a group of producers growing corn and soybeans in Iowa over a three-year period was.available from Iowa State University Extension. This information was used to assess the relative importance of ...


Evaluation Of A Liquid Chromatographic Method For The Determination Of Fumonisins In Corn, Poultry Feed, And Fusarium Culture Material., Larry G. Rice, P. Frank Ross, Jan Dejong, Ronald D. Plattner, Joel R. Coats Jul 1995

Evaluation Of A Liquid Chromatographic Method For The Determination Of Fumonisins In Corn, Poultry Feed, And Fusarium Culture Material., Larry G. Rice, P. Frank Ross, Jan Dejong, Ronald D. Plattner, Joel R. Coats

Entomology Publications

The performance of a liquid chromatographic method for determining fumonisins in corn, animal feeds, and culture material was evaluated. Efficiencies of extractions with the following solvent systems were determined: acetonitrile-water (50 + 50, v/v), methanol-water (75 + 25, v/v), and 100% water. The acetonitrile solvent gave both higher extraction efficiencies and faster extraction times than the other 2 solvents. Extraction was followed by C18 solid-phase extraction column cleanup. Fumonisin B1 (FB1), fumonisin B2 (FB2), and fumonisin B3 (FB3) were measured by precolumn derivatization with o-phthalaldehyde followed by isocratic separation on a C18 reversed-phase column with a mobile phase of 50 ...


Properties Of Sugary-2 Maize Starch: Influence Of Exotic Background., M. R. Campbell, Pamela J. White, Linda M. Pollak Jul 1995

Properties Of Sugary-2 Maize Starch: Influence Of Exotic Background., M. R. Campbell, Pamela J. White, Linda M. Pollak

Food Science and Human Nutrition Publications

Genetic modifiers of maize (Zea mays L.) starch thermal properties were examined by differential scanning calorimetry (DSC). Sugary- 2 (su2) kernels from segregating ears were identified based on textural appearance of starches following crosses between an exotic maize accession with the inbred OH43 homozygous for the su2 allele (OH43 su2). Two exotic maize accessions, PI213768 and PI451692, were used. Germs retained from su2 kernels were used to produce an F2 population of su2 plants containing 50% exotic germ plasm. With few exceptions, F2 ears from the populations were homozygous for the su2 allele. Significant (P less than or equal to ...


Characterization And Food Applications Of High Amylose And Other Varieties Of Starch , Tunyawat Kasemsuwan Jan 1995

Characterization And Food Applications Of High Amylose And Other Varieties Of Starch , Tunyawat Kasemsuwan

Retrospective Theses and Dissertations

The dominant mutant amylose-extender (Ae1-5180) maize starch is a new starch variety and is derived from spontaneous mutation. Scanning electron microscopy, gel permeation chromatography (GPC), amylose content, amylopectin chain-length, and thermal properties (gelatinization and retrogradation) indicated that the doses (1-3 doses) of the dominant gene did not affect the structure or properties of the starch. GPC and real amylose content of these starches indicated that they contained a large amount of intermediate components (≈20%). The Ae1-5180 dominant mutant starch contained 33% amylose. The amylopectin branch-chain length was shorter than that of the intermediate component. Thermal analysis indicated that the dominant ...


Production Of Aldehyde Oxidase By Streptomyces Species , Byungtae Lee Jan 1995

Production Of Aldehyde Oxidase By Streptomyces Species , Byungtae Lee

Retrospective Theses and Dissertations

Production of aldehyde oxidase (aldehyde:O[subscript]2 oxidoreductase, EC 1.2.3.1) by Streptomyces setonii 75Vi2 and Streptomyces viridosporus T7A was characterized. For S. setonii, aldehyde oxidase was initially induced in shake-flask culture in 0.6% (w/v) yeast extract medium. Inducer (propanal) concentration was determined to be 1.6 g/L medium and two propanal additions generated the best results. Inducer addition to cells in late-log phase was essential to enzyme induction. Dissolved oxygen and pH measurements were key parameters for determination of late-log phase in 15-L and 50-L batch fermentation. Aldehyde oxidase activity was 0.02 ...


Effects Of Ear Developmental Temperature On Fine Structure Of Maize Starch , Ting-Jang Lu Jan 1995

Effects Of Ear Developmental Temperature On Fine Structure Of Maize Starch , Ting-Jang Lu

Retrospective Theses and Dissertations

Two genetically unrelated normal dent maize inbreds, ICI63 and ICI92, with different heterotic backgrounds were used for studying environmental temperature effects on grain yield and quality. These two maize inbreds are used in commercially available hybrids and are proprietary to ICI Seeds. The maize inbreds were grown in a greenhouse to control the growing condition of the plants. After 14 days post-pollination, the ears were wrapped in temperature control devices set at 25 or 35∘ C during the grain-filling period. Grain yield, kernel weight, and kernel density were less for ears developing at 35∘ C than for those at 25 ...


Myofibrillar Protein Degradation Patterns And Structural Changes In Skeletal Muscle From Electrically Stimulated Bos Taurus And Bos Indicus Crossbred Cattle , Chiung-Ying Ho Jan 1995

Myofibrillar Protein Degradation Patterns And Structural Changes In Skeletal Muscle From Electrically Stimulated Bos Taurus And Bos Indicus Crossbred Cattle , Chiung-Ying Ho

Retrospective Theses and Dissertations

Degradation of titin, nebulin, desmin and troponin-T, structural changes in nonstimulated (NS) and electrically stimulated (ES) bovine skeletal muscle and comparison of these changes in Angus x Jersey (AxJ) cattle (Bos taurus cross) with the changes in Brahman x Simmental (BxS) cattle (Bos indicus cross) were determined. Myofibrils for SDS-PAGE and Western blots and intact muscle samples for transmission electron microscopy were prepared at 0, 1, 3, 7, 14 and 28 days postmortem (PM). In SDS-PAGE, ES slightly accelerated the degradation of intact titin (T1 band), nebulin, desmin and troponin-T in AxJ samples. In Western blots of AxJ samples, ES ...


Factors Affecting The Flavor Development Of Swiss Cheese , Firth Kraft Whitehouse Jan 1995

Factors Affecting The Flavor Development Of Swiss Cheese , Firth Kraft Whitehouse

Retrospective Theses and Dissertations

The flavor of Swiss cheese made from various natural and synthetic fats was compared with cheese made from the natural milk emulsion. Cheeses made from recombined milk fat and skim milk with or without the addition of gum acacia gave typical flavor similar to the natural milk emulsion. Homogenization did not have an effect on flavor of the cheese. Cheese made from recombined milk fat and skim milk plus buttermilk solids had lower typical flavor than the natural milk emulsion or cheeses made with gum acacia. Cheeses made from high-oleate sunflower oil with or without the incorporation of synthetic short-chain ...


The Relationship Between The Calpain Enzyme System And The Postmortem Degradation Of Selected Myofibrillar Proteins , Elisabeth Jane Huff Lonergan Jan 1995

The Relationship Between The Calpain Enzyme System And The Postmortem Degradation Of Selected Myofibrillar Proteins , Elisabeth Jane Huff Lonergan

Retrospective Theses and Dissertations

The protease [mu]-calpain degrades the myofibrillar proteins titin, nebulin, filamin, desmin and troponin-T. Titin and nebulin have been reported to be affected by sample preparation. This study showed that there was little difference in the rate of degradation of the intact forms due to sample preparation (whole muscle preparations vs. purified myofibrils). The postmortem degradation of titin, nebulin, filamin, desmin, and troponin-T was monitored using SDS-PAGE and Western blotting techniques at 0, 1, 3, 7, 14, 28, and 56 days postmortem. Postmortem aged samples with lower shear force values exhibited faster degradation of the five myofibrillar proteins. Similar degradation ...


Observations On The Biosynthesis Of [Alpha]-Eleostearic And Vernolic Acids And The Accumulation Of Petroselinic Acid In Somatic Carrot Embryos , Linsen Liu Jan 1995

Observations On The Biosynthesis Of [Alpha]-Eleostearic And Vernolic Acids And The Accumulation Of Petroselinic Acid In Somatic Carrot Embryos , Linsen Liu

Retrospective Theses and Dissertations

Developing somatic embryos of carrots accumulated up to 24% petroselinate of total fatty acids, most of which was incorporated into triacylglycerols. Both triacylglycerol and petroselinate accumulation in the embryos were increased by addition of abscisic acid to the culture medium. The novel phenylethyl esters of the fatty acids were used to separate petroselinate from oleate both by gas chromatography and high performance liquid chromatography. This derivative offers the fastest and most efficient method for petroselinate analysis among the published procedures;The biosynthesis of vernolic acid in the developing seed of Vernonia galamensis was explored by using (1-14C) acetate in vivo ...


Oxidative And Frying Stabilities Of Soybean Oils With Altered Fatty Acid And/Or Lipoxygenase Contents , Nuo Shen Jan 1995

Oxidative And Frying Stabilities Of Soybean Oils With Altered Fatty Acid And/Or Lipoxygenase Contents , Nuo Shen

Retrospective Theses and Dissertations

Lipoxygenase (LOX)-null soybean lines, lacking LOX 2, LOX 2 and 3 and containing normal (>8.0%) or low (<3.0%) linolenate (18:3) contents were evaluated for their room-temperature storage stability, stability during frying, and oxidative stability in bread cubes stored after frying. Six genotypes of soybeans were extracted by both laboratory-scale and pilot plant-scale systems and were refined, bleached, and deodorized in the laboratory. Citric acid was added to oils during the cool-down stage of deodorization. For each system, two replications separated at the point of conditioning were evaluated for each genotype, including Century 84, L2-3, L2L3-2-4, A89-269043, A89-269043-L2, and A89-269043-L2L3;Peroxide values (PVs), fatty acid compositions, volatile compounds, and sensory evaluation were determined for several room-temperature storage conditions. To determine stability under frying conditions, each replicate (250 g) was heated to 180 ± 5°C in a minifryer. Bread cubes were fried at the beginning of heating and after 20 h of heating. Heating of the oils was continued for 10 h each day for 3 consecutive days. Sensory evaluation of the fried cubes, the peroxide values of oils extracted from the cubes, and the conjugated dienoic acid values and polymer values of the heated oils were measured. For both room-temperature and frying-temperature tests, soybean oils with low 18:3 contents were significantly more stable than were oils with normal 18:3 contents, regardless of the LOX contents of the beans;Additional soybean genotypes that contained different amounts of palmitate (16:0) and 18:3 were evaluated for oxidative stability. Soybean oils from Hardin 91, P9322, A91-282036, and HPLL were processed and analyzed. The fatty acid compositions, peroxide values, and cloud points were measured. The results showed that elevating 16:0 and/or lowering 18:3 increased the oxidative stability of soybean oils.


Characterization And Application Of Porcine Liver Aldehyde Oxidase In The Removal Of Off-Flavors From Soy Proteins , Peeyush Maheshwari Jan 1995

Characterization And Application Of Porcine Liver Aldehyde Oxidase In The Removal Of Off-Flavors From Soy Proteins , Peeyush Maheshwari

Retrospective Theses and Dissertations

Two enzyme forms (PAO-I and PAO-II) of porcine liver aldehyde oxidase (aldehyde: oxygen oxidoreductase, EC 1.2.3.1) were purified to homogeneity using affinity chromatography. The heat treatment and ammonium sulfate fractionation steps resulted only in a partial purification. Both enzyme forms, PAO-I and PAO-II, have similar pIs of 5.8 and molecular weight of 262,000 and 255,000 daltons, respectively;The two enzyme forms exhibited different substrate specificities. Compared to PAO-II, PAO-I showed higher affinity for the medium-chain aldehydes (pentanal and hexanal) which are mainly responsible for the greeny and beany off-flavor of soybean products. The PAO-I ...


Enhanced Production, Purification, And Characterization Of Propionicin Plg-1, A Bacteriocin Produced By Propionibacterium Thoenii P127 , Hyun-Dong Paik Jan 1995

Enhanced Production, Purification, And Characterization Of Propionicin Plg-1, A Bacteriocin Produced By Propionibacterium Thoenii P127 , Hyun-Dong Paik

Retrospective Theses and Dissertations

Propionibacterium thoenii strain P127 produces the bacteriocin propionicin PLG-1. Goals of this study were to increase the sensitivity of the standard well diffusion assay system for bacteriocin activity, to improve production of propionicin PLG-1 under controlled conditions in a fermenter, and to obtain the amino acid sequence and composition of the purified bacteriocin;For the well diffusion assay, a 5-mm deep base layer that contained 2.5% agar, 0.85% NaCl and 0.1% Tween 80 was used. Plates were incubated at 37° C for 2 h before adding bacteriocin samples to the wells. Lactobacillus delbrueckii ATCC 4797 was used ...


Effect Of Heat Treatment, Irradiation And Storage Conditions On The Survival, Growth And Virulence Of Heat-Shocked Yersinia Enterocolitica In Ground Pork , Kalpana Shenoy Jan 1995

Effect Of Heat Treatment, Irradiation And Storage Conditions On The Survival, Growth And Virulence Of Heat-Shocked Yersinia Enterocolitica In Ground Pork , Kalpana Shenoy

Retrospective Theses and Dissertations

The heat shock response and thermotolerance of Yersinia enterocolitica in BHI broth and ground pork was studied. Further, the survival and growth of the heat-shocked cells following heat treatment at 55° C and stored at 4 or 25° C under air, vacuum, or modified atmosphere was also examined. Lastly, the irradiation sensitivity of the heat-shocked cells when suspended in pork and packaged either under air or vacuum was determined. As part of the research, virulence of the survivors was examined following heat treatment or irradiation;Exposure of Y. enterocolitica to 45° C for 60 mins. in BHI broth resulted in ...


Osmoconditioned Seeds As A Foodstuff , Julie Marie Goldman Jan 1995

Osmoconditioned Seeds As A Foodstuff , Julie Marie Goldman

Retrospective Theses and Dissertations

The technique of seed osmoconditioning, which consists of a controlled hydration and dehydration, was evaluated for use in foodstuff production;In the first experiment, soybean, wheat, mungbean, and sesame seeds were hydrated in polyethylene glycol (PEG), chitosan plus water (CH), citric acid (CA), and water (W). Hydrated seeds were either dehydrated to their original moisture content or left fully-hydrated and stored at 5°C or 15°C for 2 or 4 weeks. Fully-hydrated and dehydrated seeds sprouted faster than untreated seeds, but the performance of fully-hydrated seeds declined during storage. Phytate content in soybean and mungbean seeds increased with the ...


Use Of Eubacterium Coprostanoligenes To Decrease Plasma Cholesterol Concentration In Hypercholesterolemic Rabbits And The Cholesterol Content Of Fermented Meats , Uford Augustus Madden Jan 1995

Use Of Eubacterium Coprostanoligenes To Decrease Plasma Cholesterol Concentration In Hypercholesterolemic Rabbits And The Cholesterol Content Of Fermented Meats , Uford Augustus Madden

Retrospective Theses and Dissertations

The effects of Eubacterium coprostanoligenes, a cholesterol reducing bacteria, on plasma cholesterol homeostasis in hypercholesterolemic rabbits and on the cholesterol content of pork and mutton sausages were investigated. Daily oral doses of the bacteria were administered to hypercholesterolemic rabbits, and meat samples were inoculated with different amounts of bacteria and incubated for 12-15 hours at 37° C. These studies addressed the problem of human hypercholesterolemia by investigating the possibility of using E. coprostanoligenes as a model for the treatment of human hypercholesterolemia and to develop technology to decrease the cholesterol content of foods;Eighteen New Zealand White male adult rabbits ...


Water Reuse In Fermentations , Tzu-Yin Hsiao Jan 1995

Water Reuse In Fermentations , Tzu-Yin Hsiao

Retrospective Theses and Dissertations

This work was undertaken to investigate the feasibility of reusing the process effluent from fermentation processes to minimize the liquid waste. Two fermentations with different characteristics were chosen as model fermentations for development of principles. The first was a yeast fermentation that requires high levels of carbon substrate for production of intracellular lipid. The second was a bacterial fermentation requiring high levels of nitrogen in the medium for production of lysine. The latter is used for commercial production of lysine;In the study of the first model fermentation, Apiotrichum curvatum, an oleaginous yeast, was used as the working culture. Spent ...


A Muscle Hypertrophy Condition In Lamb (Callipyge): Characterization Of Effects On Muscle Growth And Meat Quality Traits, M. Koohmaraie, S. D. Shackelford, T. L. Wheeler, Steven M. Lonergan, M. E. Doumit Jan 1995

A Muscle Hypertrophy Condition In Lamb (Callipyge): Characterization Of Effects On Muscle Growth And Meat Quality Traits, M. Koohmaraie, S. D. Shackelford, T. L. Wheeler, Steven M. Lonergan, M. E. Doumit

Steven M. Lonergan

The present experiment was conducted to determine the effect of the callipyge phenotype on traits affecting muscle growth and meat tenderness. Dorset wethers (n = 40) that were either carriers or non-carriers were fed grain and slaughtered at 169 d of age. Callipyge phenotype did not affect ( P > .05) slaughter weight, hot carcass weight, or weights of the heart, spleen, viscera, kidney-pelvic fat, head, and pelt; however, callipyge lambs had a higher dressing percentage and lighter lungs, liver, and kidneys ( P < .01). Callipyge lambs had reduced fat thickness and marbling score and higher leg scores and longissimus area (34%). Adductor (30%), biceps femoris (42%), gluteus group (31%), longissimus (32%), psoas group (20%), quadriceps femoris (18%), semimembranosus (38%), and semitendinosus (26%) weights were higher in the callipyge phenotype ( P < .01); however, phenotype did not affect ( P > .05) weights of infraspinatus or supraspinatus. Longissimus pH and temperature declines were not affected ( P > .05) by phenotype. Longissimus myofibril ...


Delayed-Incubation Method For Microbiological Analysis Of Environmental Specimens And Samples, James S. Dickson, M. H. Brodsky, C. A. Davidson, M. J. Pettis, T. L. Tieso Jan 1995

Delayed-Incubation Method For Microbiological Analysis Of Environmental Specimens And Samples, James S. Dickson, M. H. Brodsky, C. A. Davidson, M. J. Pettis, T. L. Tieso

James S. Dickson

Five laboratories compared the quantitative recovery of heterotrophic bacteria, yeasts and molds, coliforms, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus from a variety of naturally contaminated food and water samples, using traditional incubation procedures and a delayed-incubation method. Refrigeration of inoculated media for up to 3 days prior to incubation was shown to be a viable option for many quantitative analyses, but needs to be validated for each application. Some inoculated media withstood refrigeration for up to 7 days prior to incubation without any detrimental effect on the recovery of target cells, while the incubation of other media for similar ...


Economic-Engineering Assessment Of Sequential Extraction Processing Of Corn, Dongil Chang, Mila P. Hojilla-Evangelista, Lawrence A. Johnson, Deland J. Myers Jan 1995

Economic-Engineering Assessment Of Sequential Extraction Processing Of Corn, Dongil Chang, Mila P. Hojilla-Evangelista, Lawrence A. Johnson, Deland J. Myers

Center for Crops Utilization Research Publications

A simulation model, termed SIMSEP for simulating the Sequential Extraction Process (SEP), was developed to assess the economic and engineering feasibilities of SEP, an innovative approach to processing corn into ethanol, edible oil, industrial and edible proteins, andfeed ingredients. SEP is designed to produce a new mix of value-added coproducts that could improve the profitability of processing corn and corn-derived ethanol. Simulations were carried out for various system variables to examine their effects on profitability. Results showed that SEP is economically and technically feasible. Estimates for return on investment for a proposed plant are attractive under many likely market situations ...


Genetic Variation For Starch Thermal And Functional Properties Among Nonmutant Maize Inbreds', M. R. Campbell, Linda M. Pollak, Pamela J. White Jan 1995

Genetic Variation For Starch Thermal And Functional Properties Among Nonmutant Maize Inbreds', M. R. Campbell, Linda M. Pollak, Pamela J. White

Food Science and Human Nutrition Publications

Differential scanning calorimetry (DSC) has been used in previous < 0.01) inbred by year interaction was present for all DSC parameters studies to detect differences in thermal properties among starches of non- with the exception of AH. Differences were observed in starch viscosities mutant maize (Zea mays L.) genotypes. This study was conducted to and gel strengths for six inbreds selected for highest and lowest Tp, AH, determine the magnitude of genetic and genotype by environmental effects and range (R,). Several significant (P < 0.05) correlations occurred on starch properties among a set of exotic and domestic inbred lines. between DSC parameters and starch paste viscosities and gel strengths. Functional properties of starches from selected lines exhibiting extreme These data suggest that evaluation of starches from nonmutant genotypes DSC values also were investigated. Highly significant (P< 0.01) differences by DSC can be used to predict some functional properties. A practical for DSC starch thermal properties were seen among the lines. Starches application of DSC in breeding programs may include screening maize from exotic lines generally had lower gelatinization onset temperature germplasm for extreme DSC values or population improvement through (TO), peak temperature (Tp), and enthalpy (AH). A highly significant (P recurrent selection. The maize wet-milling industry produces a number of starch- based products important in the food industry. Genetic variability in starch structure and functional properties has led to the use of specialty starches from waxy and high-amylose genotypes (Shannon and Garwood 1984). More recently, the introduction of starches containing double mutant combinations with proper- ties similar to chemically modified starches has resulted in several patents (Katz 1991). The application of differential scanning calorimetry (DSC) to the study of starch was first described by Stevens and Elton (1971). This technique offers a thermodynamic approach to the study of starch gelatinization by monitoring changes in the physical and chemical properties of starches (Donovon et al 1983). Use of DSC in investigating the thermal behavior of starches has become increasingly more popular because it requires only a small sample size and is easy to operate (Sanders et al 1990). Addi- tionally, DSC is relatively rapid compared with more traditional methods of studying starch gelatinization, making it suitable for breeding programs. Extensive variations in DSC parameters have been observed among starches of single- and double-mutant genotypes of maize indicating differences in starch structure and function (Brockett et al 1988, Sanders et al 1990, Wang et al 1992). More recent studies have revealed variations in DSC parameters among non- mutant sources of maize starch. Krueger et al (1987), for example, found differences in DSC parameters among two maize inbred lines and suggested that AH and peak height index (PHI) could be used as a means of identifying maize genotypes. White et al (1990) reported variability in thermal properties by DSC in genetically variable maize populations. The largest differences were observed for gelatinization onset (T.), range (Rn), and total enthalpy (AH). In addition, Li et al (1994) found large variations in DSC values among several exotic populations of maize, sug- gesting that selection among these on the basis of DSC values would identify genotypes having desired starch properties.