Ivan A. Wolff

Bio: Ivan A. Wolff is an academic researcher from United States Department of Agriculture. The author has contributed to research in topics: Catalysis & Linoleic acid. The author has an hindex of 12, co-authored 20 publications receiving 778 citations.

The search for new industrial crops

Abstract: Advances in technological development have produced an ever-increasing pressure for new and different raw materials to keep pace with changing industrial needs. Many new and useful properties of plants may be discovered through the modern chemistry and technology of utilization research. The U. S. Department of Agriculture’s search for new industrial crops is a coordinated botanical and utilization research program.

Distribution of rotenone and deguelin in Tephrosia vogelii and separation of rotenoid-rich fractions

Abstract: Rotenone and deguelin were determined by thinlayer densitometry in seven varieties of Tephrosia vogelii. The leaflets contained more deguelin than rotenone; the reverse was generally found in the petioles, stems, and roots. One variety contained deguelin but no rotenone. In other varieties the leaflets had more rotenone than other parts of the plant, and several times as much deguelin. Fractionation to recover rotenoid-rich leaflets was pas ible because they were more friable than stem portions of partially dried plants. Minimizing

An octadecatrienoic acid from Lamium purpureum L. seed oil containing 5,6-allenic and trans-16-olefinic unsaturation.

Abstract: 1. Lamium purpureum L. (Labiatae) seed oil contains 16% of a new acid characterized as (−)-octadeca-5,6-trans-16-trienoic acid (proposed trivial name `lamenallenic acid') (Ia). The acid was isolated as its methyl ester by countercurrent distribution by using a combination of recycle–single withdrawal techniques. Methyl lamenallenate (Ib) is strongly laevorotatory. 2. The structure was established by infrared spectroscopy, nuclear-magnetic-resonance spectroscopy, quantitative hydrogenation and oxidative cleavage data of the original acid and of hydrazine partial reduction products. 3. Other unsaturated esters identified by their cleavage products were oleate, linoleate and linolenate. 4. A very small amount (less than 1%) of methyl laballenate [(−)-methyl octadeca-5,6-dienoate] was also isolated and identified.

Fatty acid and polar lipid composition in the classification of Cellulomonas, Oerskovia and related taxa

Abstract: Strains representing the taxa Cellulomonas, Oerskovia, Brevibacterium fermentans, Corynebacterium manihot and Nocardia cellulans were degraded by acid methanolysis and the non-hydroxylated fatty acid esters released examined by thin-layer and gas chromatography. The major fatty acid in all strains was 12-methyltetradecanoic acid (anteiso C15) which occurred together with other anteiso acids, iso and straight-chain acids. The fatty acid profiles of the cellulomonads were distinguished by the presence of 13-carbon acids and significantly higher proportions of straight-chain acids than found in the other test strains whose profiles were closely similar to one another. Two-dimensional thin-layer chromatography showed that almost identical and very characteristic polar lipid patterns were given by all the organisms under study: the only major components were diphosphatidylglycerol, phosphatidylinositol and two phospho-glycolipids chromatographing similarly to, but distinguishable from, the mono- and diacyl phosphatidylinositol dimannosides characteristic of Nocardia and other actinomycetes. The accumulated lipid data support the reclassification of B. fermentans, Cor. manihot and N. cellulans in the genus Oerskovia.

Lipids in the Classification and Identification of Coryneform Bacteria Containing Peptidoglycans Based on 2, 4-diaminobutyric Acid

Abstract: Strains of 2, 4-diaminobutyric acid-containing coryneform bacteria were degraded by acid methanolysis and the non-hydroxylated fatty acid esters released examined by thin-layer and gas chromatography. The major fatty acid structural types were straight-chain, anteiso- and iso-methyl branched-chain acids. Polar lipids of the test strains were examined by two-dimensional thin-layer chromatography. All strains possessed very characteristic polar lipid patterns consisting of diphosphatidylglycerol, phosphatidylglycerol and a number of uncharacterized glycolipids. Menaquinones (vitamin K) were the sole isoprenoid quinones detected in the test strains. Corynebacterium insidiosum, Cor. michiganense, Cor. nebraskense and Cor. sepedonicum contained unsaturated menaquinones with nine isoprene units, whereas unsaturated menaquinones with 10 isoprene units predominated in strains of Cor. iranicum and Cor. tritici and a strain labelled Arthrobacter sp. The single strain of Cor. aquaticum examined contained comparable amounts of menaquinones with 10 and 11 isoprene units whereas strains of Cor. mediolanum and Flavobacterium dehydrogenans contained major amounts of menaquinones with 11 and 12 isoprene units. The results of the present study indicate that lipid markers may be of considerable value in the classification and identification of 2, 4-diaminobutyric acid-containing phytopathogenic and saprophytic coryneform bacteria.

Analysis of bacterial menaquinone mixtures by high performance liquid chromatography

Abstract: Menaquinone mixtures of microbial origin were separated according to the chain length and the degree of hydrogenation of the polyisoprenyl side-chain by reversephase partition high performance liquid chromatography. Menaquinones can be measured easily and sensitively by the chromatographic system described here.