Enhancing quality and oxidative stability of aged fried food with gamma-tocopherol.

To determine the effects of gamma-tocopherol on the stability of fried food, potato chips were fried in triolein with 0, 100, or 400 ppm gamma-tocopherol. Potato chips, sampled at 1, 3, and 6 h of frying time, were aged for 0, 2, and 4 days at 60 degrees C and then evaluated for odor attributes by sensory analysis and for volatile compounds by purge-and-trap gas chromatography-mass spectrometry. Oil sampled after 1, 3, and 6 h of frying time from the fryer was evaluated for total polar compounds and retention of gamma-tocopherol.

A rapid method for extraction of zearalenone and zeraralenols in fermented corn.

A rapid extraction method is described for isolation of zearalenone and α- and β-trans-zearalenols from laboratory fermented corn. Corn fermented withFusarium crookwellense at 25°C for 2 weeks was agitated for 5 minutes in acetone. The acetone extract was evaporated to dryness and the remaining residue was chromatographed on a silica gel column with hexane:ethyl acetate (8:2).

Growth, death, and oxygen uptake kinetics of Pichia stipitis on xylose.

Pichia stipitis NRRL Y-7124 has potential application in the fermentation of xylose-rich waste streams, produced by wood hydrolysis. Kinetic models of cell growth, death, and oxygen uptake were investigated in batch and oxygen-limited continuous cultures fed a rich synthetic medium. Variables included rates of dilution (D) and oxygen transfer (K(1)a) and concentrations of xylose (X), ethanol (E), and dissolved oxygen (C(ox)).

Metabolites of cis,trans, and trans,cis isomers of linoleic acid in mice and incorporation into tissue lipids.

Metabolism of octadecadienoic acid isomers in weanling mice was studied by feeding fat-free diets supplemented with 2% by weight of cis-9,trans-12-octadecadienoic acid (c,t-18:2-d0), tetradeuterated trans-9,cis-12-octadecadienoic acid (t,c-18:2-d4) or dideuterated cis-9,cis-12-octadecadienoic acid (c,c-18:2-d2). Rates for conversion of c,t-18:2-d0 and c,c-18:2-d2 to c,t-20:4-d0 and c,c-20:4-d2 were identical and both were 5-times higher than conversion of t,c-18:2-d4 to t,c-20:4-d4. Accumulation of t,c-18:2-d4 in liver lipids was 2-4-times higher than for c,t-18:2-d0 or c,c-18:2-d2.

Reactivity of Deoxynivalenol (Vomitoxin) Monoclonal Antibody Towards Putative Trichothecene Precursors and Shunt Metabolites.

The reactivity of deoxynivalenol (DON) monoclonal antibody 6F5 towards trichothecenes and Fusarium metabolites associated with DON and T-2 toxin biosynthesis was assessed by indirect enzyme-linked immunosorbent assay. Using concentrations required to inhibit antibody binding to a DON hemisuccinate ovalbumin conjugate solid phase by 50% as a basis of comparison, isotrichodermin, 3-acetyl DON, 15-deacetylcalonectrin, and 3,15-dideacetylcalonectrin were 647, 362, 247, and 209% cross-reactive relative to DON, respectively. Isotrichodermol, sambucinol, and 7,8-dihydroxycalonectrin reacted to a lesser extent.

Dithyreanitrile: an unusual insect antifeedant from Dithyrea wislizenii.

Dithyreanitrile, a novel sulfur-containing indole alkaloid, was isolated from the seeds of Dithyrea wislizenii (Cruciferae). Dithyreanitrile inhibits feeding of fall armyworm (Spodoptera frugiperda) and European corn borer (Ostrinia nubilalis) larvae. Dithyreanitrile, the first natural product with two sulfur atoms and a nitrile attached to the same carbon, was characterized by X-ray diffraction, spectroscopy, and chemical synthesis.

Multiple zeins from maize endosperms characterized by reversed-phase high performance liquid chromatography.

The major storage proteins of maize (Zea mays L.) endosperm are located in protein bodies, and may be separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) into two major classes and four minor classes of polypeptides. The two major classes (commonly known as zeins) have been separated previously into a large number of components by isoelectric focusing (IEF).

Fermentation and aerobic metabolism of cellodextrins by yeasts.

The fermentation and aerobic metabolism of cellodextrins by 14 yeast species or strains was monitored. When grown aerobically, Candida wickerhamii, C. guilliermondii, and C.

Fractionation of egg and soybean phosphatidylcholines by silver resin chromatography.

Samples of egg and soybean phosphatidylcholines were fractionated by total number of double bonds on silver ion-saturated resin columns using solvent programming (acetonitrile in methanol). Stainless-steel columns were packed with 15-microns resin which had been isolated by air elutriation. Methods of column packing, silver ion incorporation, solvent-resin interactions and resin regeneration are also discussed.

Limonoid antifeedants from seed of Sandoricum koetjape.

An extract of the seed of Sandoricum koetjape has yielded two new limonoids, sandoricin [1] and 6-hydroxysandoricin [2]. Both compounds are effective antifeedants when incorporated into artificial diets and fed to fall armyworm (Spodoptera frugiperda) or European corn borer (Ostrina nubilalis) larvae. Reduced growth rates and increased times to pupation were evident at lower dose levels while significant mortality was noted at higher dose levels.

Phylogenetic relationships among species of Saccharomyces, Schizosaccharomyces, Debaryomyces and Schwanniomyces determined from partial ribosomal RNA sequences.

Species of the genera Saccharomyces, Schizosaccharomyces, Debaryomyces and Schwanniomyces were compared from their extent of divergence in three regions from small (18S) and large (25S) subunit ribosomal RNAs comprising a total of 900 nucleotides. With the exception of the closely related Saccharomyces bayanus and S. pastorianus, which appear to have identical sequences, all other species could be distinguished by nucleotide differences in a variable region of the large subunit, and genus-specific nucleotides were discernible in all three regions.

Mycotoxin formation by different geographic isolates of Fusarium crookwellense.

Eighteen Fusarium crookwellense isolates from the continents of Australia, Europe, and North America were compared for their ability to produce mycotoxins on corn at 25 degrees C after 2 weeks. Extracts from corn fermented with each Fusarium isolate were analyzed by thin-layer chromatography (TLC) and gas chromatography/mass spectroscopy (GS/MS) for mycotoxins. Toxins detected were zearalenone (13 isolates), fusarin C (11 isolates), nivalenol (4 isolates), and diacetoxyscirpenol (2 isolates).

Aspergillus flavus and aflatoxins B1, B2, and M1 in corn associated with equine death.

Corn from an Arkansas farm, where three horses died and others became sick, was investigated for causative principles. Necropsy of the three horses revealed what appeared to be severe hepatic necrosis. Histopathological examination indicated a pattern of hepatic lesions that was suggestive of aflatoxin contamination of the feed.

Sugar uptake and starch biosynthesis by slices of developing maize endosperm.

(14)C-Sugar uptake and incorporation into starch by slices of developing maize (Zea mays L.) endosperm were examined and compared with sugar uptake by maize endosperm-derived suspension cultures. Rates of sucrose, fructose, and d- and l-glucose uptake by slices were similar, whereas uptake rates for these sugars differed greatly in suspension cultures.

Carbon Concentration and Carbon-to-Nitrogen Ratio Influence Submerged-Culture Conidiation by the Potential Bioherbicide Colletotrichum truncatum NRRL 13737.

We assessed the influence of various carbon concentrations and carbon-to-nitrogen (C:N) ratios on Colletotrichum truncatum NRRL 13737 conidium formation in submerged cultures grown in a basal salts medium containing various amounts of glucose and Casamino Acids. Under the nutritional conditions tested, the highest conidium concentrations were produced in media with carbon concentrations of 4.0 to 15.

Production of a novel steroid sulfate metabolite [4,4,24-trimethylcholesta-8,14,24(28)-trien-2 alpha,3 beta,11 alpha,12 beta-tetrol 12-acetate, 3-sulfate] by Fusarium species and its biological activity.

A novel steroid sulfate, 4,4,24-trimethylcholesta-8,14-24(28)-trien-2 alpha,3 beta,11 alpha,12 beta- tetrol 12-acetate, 3-sulfate, was discovered in Fusarium spp. Forty Fusarium strains belonging to F. sporotrichioides, F.

Physiology and genetics of xylan degradation by gastrointestinal tract bacteria.

Hemicelluloses or xylans are major components (35%) of plant materials. For ruminant animals, about 50% of the dietary xylans are degraded, but only small amounts of xylans are degraded in the lower gut of nonruminant animals and humans. In the rumen, the major xylanolytic species are Butyrivibrio fibrisolvens and Bacteroides ruminicola.

Sprayable self-encapsulating starch formulations for Bacillus thuringiensis.

Under glasshouse conditions, various cornstarches and adjuvants were examined as encapsulating agents in sprayable formulations for Bacillus thuringiensis subsp. kurstaki Berliner. When these materials were suspended in water and tested for physical factors such as viscosity, clumping, and retention on plant surfaces, a range of responses was observed.

Fumonisin B1: Isolation from corn culture, and purification by high performance liquid chromatography.

A method is described to isolate fumonisin B1 (FB1) from corn cultured for 18 days at 25°C withFusarium moniliforme. Cultured corn was extracted with aqueous methanol and purified with XAD-2 column chromatography and high performance liquid chromatography (HPLC). About 450 mg of FB1 were obtained from 800g cultured corn.

Transport of glucose and cellobiose by Candida wickerhamii and Clavispora lusitaniae.

The cellular location of beta-1,4-glucosidase activity from, as well as the transport of glucose and cellobiose into, cells of Clavispora lusitaniae NRRL Y-5394 and Candida wickerhamii NRRL Y-2563 was investigated. The beta-glucosidase from Cl. lusitaniae appeared to be a soluble cytoplasmic enzyme.

Sugar metabolism in germinating soybean seeds: evidence for the sorbitol pathway in soybean axes.

Characterization of sugar content and enzyme activity in germinating soybean (Glycine max L. Merrell) seeds led to the discovery of sorbitol accumulating in the axes during germination. The identity of sorbitol was confirmed by relative retention times on high-performance liquid chromatography and gas liquid chromatography and by mass spectra identical with authentic sorbitol.

Cloning, sequencing, and expression of a xylanase gene from the anaerobic ruminal bacterium Butyrivibrio fibrisolvens.

A gene coding for xylanase activity, xynA, from the anaerobic ruminal bacterium Butyrivibrio fibrisolvens 49 was cloned into Escherichia coli JM83 by using plasmid pUC19. The gene was located on a 2.3-kilobase (kb) DNA insert composed of two adjacent EcoRI fragments of 1.

Bacillus thiaminolyticus sp. nov., nom. rev.

The name "Bacillus thiaminolyticus" Kuno 1951 was not included on the Approved Lists of Bacterial Names and has lost standing in bacteriological nomenclature. The genetic homogeneity of "Bacillus thiaminolyticus" was assessed by determining guanine-plus-cytosine contents by the buoyant density method and by measuring DNA relatedness by using spectrophotometric reassociation procedures. Of the 26 strains which I studied, 24 had guanine-plus-cytosine contents in the range from 52 to 54 mol%.

RUTHENIUM RED INHIBITION OF OXYGEN EVOLUTION AND SPECIFIC RELEASE OF THE EXTRINSIC 16 kDa POLYPEPTIDE IN A PHOTOSYSTEM II PREPARATION.

The inhibitory effect of the dye ruthenium red was studied in photosystem II-enriched submembrane fractions. A number of distinct types of interaction were found, which differed in their concentration range and required incubation time. Ruthenium red instantaneously quenches the initial chlorophyll a fluorescence level (F ) and the maximum fluorescence level (F ) by enhancing radiationless deactivation in the chlorophyll light harvesting complex.