A novel sphingophosphonolipid head group 1-hydroxy-2-aminoethyl phosphonate in Bdellovibrio stolpii

Members of the bacterial genus Bdellovibrio include strains that are free-living whereas others are known to invade and parasitize larger Gram-negative bacteria. The bacterium can synthesize several sphingophospholipid compounds including those with phosphoryl bonds as well as phosphonyl bonds. In the present study, the dominant sphingophosphonolipid component was isolated by column chromatography, and the long-chain bases, fatty acids, and polar head groups were identified by thin-layer and gas-liquid chromatographic procedures. The definitive structural identity of the sphingolipid was established by nuclear magnetic resonance and mass spectrometry of hydrolysis products and the intact compound. The compound was identified as N-2′-hydroxypentadecanoyl-2-amino-3,4-dihydroxyheptadecan-1-phosphono-(1-hydroxy-2-aminoethane).     

Components of Honeybee Royal Jelly as Deterrents of the Parasitic <Emphasis Type="Italic">Varroa</Emphasis> Mite, <Emphasis Type="Italic">Varroa destructor</Emphasis>

The parasitic mite Varroa destructor Anderson & Trueman reproduces on the immature stage of the honeybee, Apis mellifera L. Mites are found more often on drone brood than worker brood and only infrequently on queen brood. We investigated the chemical basis for the low incidence of mites on queen brood. V. destructor mites were deterred by a crude extract of royal jelly, a glandular secretion produced by nurse bees and fed to queen larvae. Bioassay-driven fractionation of the crude extract via column chromatography resulted in one active fraction that was as active as the crude extract. Compounds in the active fraction were identified using gas chromatography (GC) and coupled gas chromatography/mass spectrometry (GC-MS). Before injection, compounds were esterified with MeOH/sulfuric acid, followed by silylation of any hydroxyl groups present. The active fraction contained at least 22 compounds, all fatty acids, several of which contained an additional hydroxyl group on the alkyl chain. Synthesis of some of these compounds that are not commercially available is described. A synthetic mixture containing most of the compounds in the active fraction was as active as the active fraction in the bioassay.     

Lipid composition ofNeurospora crassa

The lipids ofNeurospora crassa, isolated in pure form from freeze-dried mycelium, were found to contain squalene, sterol esters, triglycerides, free fatty acids, geranylgeraniol, free sterols, carotenoids, cardiolipin, phosphatidyl ethanolamine, phosphatidyl choline, phosphatidyl serine, and phosphatidic acid. The above compounds were isolated in pure form by column and thin layer chromatography and were characterized by infrared spectroscopy and chromatographic mobilities. Fatty acid moieties were characterized by gas liquid chromatographic retention times of their methyl esters relative to those of authentic standards. The fatty acid composition of the triglycerides was found to be similar to that of phosphatidic acid, cardiolipin, and lecithin.     

Concentration and purification of stearidonic,eicosapentaenoic, and docosahexaenoic acids from cod liver oil and the marine microalgaIsochrysis galbana

n-3 Polyunsaturated fatty acids (n-3 PUFA) from the marine microalgaIsochrysis galbana were concentrated and purified by a two-step process—formation of urea inclusion compounds followed by preparative high-performance liquid chromatography. These methods had been developed previously with fatty acids from cod liver oil. By the urea inclusion compounds method, a mixture that contained 94% (w/w) stearidonic (SA), eicosapentaenoic (EPA), plus docosahexaenoic (DHA) acids (4:1 urea/fatty acid ratio and 4°C crystallization final temperature) was obtained from cod liver oil fatty acids. Further purification of SA, EPA, and DHA was achieved with reverse-phase C₁₈ columns. These isolations were scaled up to a semi-preparative column. A PUFA concentrate was isolated fromI. galbana with methanol/water (80:20, w/w) or ethanol/water (70:30, w/w). With methanol/water, a 96% EPA fraction with 100% yield was obtained, as well as a 94% pure DHA fraction with a 94% yield. With ethanol/water as the mobile phase, EPA and DHA fractions obtained were 92% pure with yields of 84 and 88%, respectively.     

Fatty acid compositions of lipid fractions from vegetative cells and mature sorocarps of the cellular slime moldDictyostelium discoideum

A wild-type strain ofDictyostelium discoideum was grown uponAerobacter aerogenes. Fatty acid compositions of lipid fractions and of total lipids obtained from vegetative amoebae and mature sorocarps were compared. Fatty acids isolated from vegetative cells were found to include large quantities of 17- and 19-carbon cyclopropane fatty acids while straight-chain, saturated fatty acids represented only 10% (w/w) of total fatty acids. These cyclopropane fatty acids appear to be derived from ingested bacteria and are preferentially incorporated into neutral lipids of the slime mold. Development of amoebae to mature sorocarps is accompanied by a substantial decrease in cyclopropane fatty acid content and a concomitant increase in unsaturated fatty acids, mostly as octadeca-5,11-dienoic acid. The †-22 stigmastenyl ester fraction is the richest source of this acid. Fully 65% of the fatty acids in this fraction are the octadecadienoate.     

Study of color stability of tall oil fatty acids through isolation and characterization of minor constituents

Minor constituents in high quality tall oil fatty acids have been isolated successfully by liquid column chromatography, using silicic acid as the adsorbent. The minor constituents contained two types of compounds: those which were noneffective and those which were effective in causing the darkening of tall oil fatty acids during heating. The former consisted oftrans-3,5-dimethoxystilbene and rosin acids. The latter was separated into numerous fractions by the combination of chemical methods, silicic acid column chromatography, and low temperature fractional crystallization. The fractions were characterized by functional group analyses, chemical reactions, and UV and IR spectrometric methods. Most of the fractions contained two-three times as much oxygen in the molecule as the original sample and were highly oxidized fatty acids. They had mol wt ranging 300–551 and contained double bonds, carbonyl, ester, peroxide, and hydroxyl groups. The effect of these minor constituents upon the color stability of tall oil fatty acids during heating was postulated as being due to the hydroxyl groups located in the α-position to the double bond in the molecule.     

Isolation and identification of trans -3,5-dimethoxystilbene from high quality tall oil fatty acids by liquid chromatography and mass spectrometry

trans-3,5-Dimethoxystilbene has been isolated from high quality tall oil fatty acids (unsaponifiables 1.5% maximum, rosin acids 1.5% maximum), using liquid column chromatography and low temperature solvent fractional crystallization. The structure of this compound was determined with the aid of IR, mass and NMR spectrometry. Thetrans-3,5-dimethyoxystilbene was found to be responsible for the development of a red color during the epoxidation of the tall oil fatty acids. Paper of the Journal Series, New Jersey Agricultural Experiment Station, Rutgers, The State University.     

The Multifaceted Inhibitory Effects of an Alkylquinolone on the Diatom Phaeodactylum tricornutum

The mechanisms underlying interactions between diatoms and bacteria are crucial to understand diatom behaviour and proliferation, and can result in far-reaching ecological consequences. Recently, 2-alkyl-4-quinolones have been isolated from marine bacteria, both of which (the bacterium and isolated chemical) inhibited growth of microalgae, suggesting these compounds could mediate diatom–bacteria interactions. The effects of several quinolones on three diatom species have been investigated. The growth of all three was inhibited, with half-maximal inhibitory concentrations reaching the sub-micromolar range. By using multiple techniques, dual inhibition mechanisms were uncovered for 2-heptyl-4-quinolone (HHQ) in Phaeodactylum tricornutum. Firstly, photosynthetic electron transport was obstructed, primarily through inhibition of the cytochrome b₆f complex. Secondly, respiration was inhibited, leading to repression of ATP supply to plastids from mitochondria through organelle energy coupling. These data clearly show how HHQ could modulate diatom proliferation in marine environments.     

Characterization of porcine omental lipids

Porcine omental lipid extracts were fractionated and the major lipid components characterized. Approximately 97% of the chloroform/methanol extract consisted of triglycerides containing primarily 16∶0, 18∶0, 18∶1, and 18∶2 fatty acids. Small quantities of free fatty acids, cholesterol, di- and monoglycerides were also detected. The phospholipid fraction, obtained by solvent partition and Unisil column chromatography and characterized by high performance liquid chromatography (HPLC) and HPLC-mass spectrometry, was found to consist primarily of phosphatidylcholine, sphingomyelin, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol. The neutral glycolipids, isolated by solvent partition and Unisil column chromatography and identified by HPTLC and HPLC, were found to consist primarily of di-, tri-and tetraosylceramides. The complex glycolipid fraction, obtained from Folch upper phase solvent partition and characterized by HPTLC and immunoblotting, was found to consist primarily of ganglio-, globo-, and neolacto- neutral glycolipids and ganglio-, globo-, neolacto- and fucosylated gangliosides.     

Characterization of feline omentum lipids

Feline omental lipid extracts, previously reported to be angiogenic in the cornea of rabbits, were fractionated and the major lipid components characterized. Approximately 97% of the chloroform/methanol extract consisted of triglycerides containing primarily 16∶0, 18∶0, 18∶1 and 18∶2 fatty acids. Trace quantities of free fatty acids, cholesterol, di- and monoglycerides were also detected. The phospholipid fraction, obtained by solvent partition and Unisil column chromatography and characterized by high performance liquid chromatography (HPLC)-mass spectrometry, was found to consist of phosphatidylcholine, sphingomyelin, phosphatidylethanolamine and phosphatidylserine. The neutral glycolipids, isolated by solvent partition and Unisil column chromatography and identified by high performance thin layer chromatography and HPLC of their perbenzoylated derivatives, were found to consist of glucosyl- and galactosylceramides, galabiosylceramide, lactosylceramide, globotriaosylceramide and globotetraosylceramide. The complex glycolipid fraction, obtained from Folch upper phase solvent partition, was found to consist primarily of Forssman glycolipid and gangliosides GM₃ and GD₃. Smaller amounts of GM₁ and other unidentified gangliosides were also present. The ganglioside nomenclature is according to the system of Svennerholm (J. Neurochem. 10, 613–623, 1963)     

Lipid and fatty acid compositions of a novel docosahexaenoic acid-producing marine bacterium

An unidentified bacterial strain, SCRC-21406, isolated from the intestine of a marine fish, Glossanodon semifasciatus, produced docosahexaenoic acid at 23% (mol/mol) [=28% (w/w)] of total fatty acids in a medium containing 0.5% (wt/vol) peptone and 0.1% (wt/vol) yeast extract at 12°C under atmospheric pressure. The cell yield was 0.43 g/L. The major lipids of the strain were phosphatidylethanolamine and phophatidylglycerol. Docosahexaenoic acid was localized at the sn-2 positions of both phospholipids. The amounts of polyunsaturated fatty acids other than docosahexaenoic acid were extremely small [<3% (mol/mol)]. Monousaturated fatty acids of the cis-7, cis-9 and cis-11 types were detected.     

Rapid determination of free fatty acids in vegetable oils by gas liquid chromatography

Determination of the free fatty acids in small quantities of vegetable oil is accomplished by gas liquid chromatography. The free fatty acids are isolated from a hexane solution of the vegetable oil into an aqueous solution of trimethylphenylammonium hydroxide (TMPH). Due to the alkalinity of TMPH, the free fatty acids readily partition into this aqueous phase. Injection of the free fatty acid-TMPH salts into a gas chromatograph results in pyrolytic methylation of the free fatty acid salts—yielding the methyl esters. Excellent results were obtained when this new procedure was used on neutral lipid oils containing known amounts of free fatty acids and compared with the results obtained by a modified BF₃/MeOH esterification procedure. When compared to the AOCS titration procedure, this new procedure gave comparable results. This new procedure has advantages over the AOCS procedure: it is more sensitive and gives quantitative results for individual free fatty acids. This new procedure also has several advantages over the modified BF₃/MeOH esterification procedure: it is easily and more rapidly performed, there is no deposition of glyceride on the column when the sample is injected, and because there is quantitative recovery, the new procedure is more sensitive and can be used on oils with a low weight percentage of free fatty acids.     

Non-Polar Lipid Components of Human Cerumen

Human cerumen was separated by column chromatography into the following groups of compounds: hydrocarbons, squalene, wax esters and cholesterol esters, triacylglycerols, free fatty acids, free fatty alcohols, monoacylglycerols, free cholesterol, free sterols, and free hydroxy acids. The groups of compounds obtained were examined in detail by gas chromatography and gas chromatography–mass spectrometry. In total, about one thousand compounds have been identified.     

Fat-Soluble Bioactives,Fatty Acid Profile and Radical Scavenging Activity of <Emphasis Type="Italic">Semecarpus anacardium</Emphasis> Seed Oil

Semecarpus anacardium (family Anacardiaceae) has many applications in the Ayurvedic and Siddha systems of medicine in India. Detailed knowledge on the composition of S. anacardium oil, in consideration of potential utilization, is of major importance. In this investigation, column chromatography, gas chromatography, thin layer chromatography and liquid chromatography techniques were performed to analyze lipid classes, fatty acids and fat-soluble bioactives of S. anacardium crude seed oil. The amount of neutral lipids in the crude seed oil was the highest, followed by glycolipids and phospholipids, respectively. Linoleic followed by palmitic and oleic were the major fatty acids. The ratio of unsaturated fatty acids to saturated fatty acids was higher in neutral lipid classes than in the polar lipids. The main sterol compounds were β-sitosterol, campesterol and stigmasterol. δ-Tocopherol followed by β-tocopherol were the main tocopherols. When S. anacardium seed oil and extra virgin olive oil were compared for their radical scavenging activity toward 1,1-diphenyl-2-picrylhydrazyl radical and galvinoxyl radical (by electron spin resonance spectrometry), S. anacardium seed oil exhibited a stronger RSA.     

Isolation of brominated long-chain fatty acids from the phospholipids of the tropical marine spongeAmphimedon terpenensis

Preliminary investigation of the phospholipid fatty acid composition of the tropical marine spongeAmphimedon terpenensis by gas chromatography/mass spectrometry revealed the presence of some novel brominated fatty acids. Two new brominated fatty acids, (5E, 9Z)-6-bromo-5,9-tetracosadienoic acid (2a) and (5E, 9Z)-6-bromo-5,9-pentacosadienoic acid (3a) were subsequently isolated from a chloroform/methanol (3∶1, vol/vol) extract of the sponge and characterized as their methyl esters 2b and 3b. The known brominated fatty acid (5E, 9Z)-6-bromo-5,9-hexacosadienoic acid (4a) was also isolated. The new fatty acid methyl esters were confirmed as brominated δ5,9 acid derivatives by chemical ionization mass spectrometry. The position of the bromine substituent was determined to be C-6 by nuclear magnetic resonance techniques while the stereochemistry of the two double bonds was deduced by nuclear Overhauser enhancement difference spectroscopy. The biosynthetic implications of the co-occurrence of the three brominated acids are discussed.     

Analysis of exoskeleton triglycerides ofLeptinotarsa decemlineata say

The exoskeleton triglyceride fraction isolated from the Colorado beetle,Leptinotarsa decemlineata Say, was studied. Analysis of the hydrolysis products and direct capillary column gas chromatography showed that, apart from triglycerides, the fraction contained no diol lipids. The composition of the natural triacylglccerol mixture was assessed by gas chromatography and by field desorption and electron impact mass spectrometry. Triglycerides isolated from the Colorado beetle are typical glycerol triesters, with long chain (mainly oleic or palmitic) fatty acids. The structures of two major components (91%), i.e., trioleoyl glycerol and 1,2-dioleoyl-3-palmitoyl glycerol, were determined.     

Peculiar properties of lipase fromCandida parapsilosis (Ashford) langeron and talice

A newCandida parapsilosis lipase was isolated and studied. This enzyme was purified by hydrophobic chromatography on a phenyl-sepharose CL4B column followed by gel permeation on a Sephacryl S300 HR column. It was a 160 kg·mol⁻¹ molecular-weight oligomeric enzyme. Optimal activity was obtained at 45°C and pH 6.5. The lipase activity toward various acylglycerols and esters was studied. The hydrolysis rate was greater for secondary acylesters than for primary acylesters. This lipase showed a high specificity for long-chain fatty acids and particularly for polyunsaturated fatty acids. This enzyme was able to catalyze the synthesis of various oleoylesters in aqueous medium.     

Characterization of Aroma-Active Compounds in Iranian cv. Mari Olive Oil by Aroma Extract Dilution Analysis and GC–MS-Olfactometry

Aroma, aroma‐active compounds and fatty acid profiles of Iranian olive oil obtained from the cv. Mari were investigated for the first time in the current study. Aroma extracts were isolated from the oil by using a purge and trap extraction system and their compositions were analyzed by gas chromatography‐mass spectrometry‐olfactometry (GC–MS‐O). A total of 35 aroma compounds comprising alcohols, aldehydes, acids, esters, ketones, terpenes and volatile phenols were identified and quantified in the assayed samples. Aldehydes were present at the highest levels, followed by ketones and alcohols. (E)‐2‐Hexenal was quantitatively (1589 µg kg^?1) the main aroma compound in the analyzed oils, followed by hexanal and (E)‐2‐heptenal. The aroma‐active volatiles were elucidated in the aromatic extract by applying aroma extract dilution analysis (AEDA). The results of AEDA revealed 17 aroma‐active compounds. Under these condition it was possible to completely identify 16 of these compounds. Regarding to the flavor dilution (FD) factor, the most potent odorants with the highest FD factor were (E)‐2‐hexenal (512), followed by hexanal, 6‐methyl‐5‐hepten‐2‐one, (E)‐2‐decenal and one unknown compound (LRI = 1871). The fatty acid profile of the tested oils was composed of thirteen compounds. Oleic acid was the main fatty acid (76.01 %) followed by palmitic acid.     

Gas-liquid chromatographic analysis of cyclopropenoid fatty acids

A method is described for the analysis of cyclopropenoid fatty acids in oils. The method consists of reacting the methyl esters of the cyclopropenoid fatty acids with silver nitrate in methanol to form ether and ketone derivatives. The derivatives formed from the cyclopropenoid fatty acids are separated from the methyl esters of the normal fatty acids by gas-liquid chromatography on a 15% diethylene glycol succinate column. The method is applicable to oils containing from 0.01% to 100% of cyclopropenoid fatty acids. The derivatives of oils containing lew levels of cyclopropenoids are separated from the normal methyl esters by alumina chromatography prior to gas-liquid chromatography. Studies on the quantitative aspects of the derivative formation, alumina chromatography, and gas-liquid chromatography are reported. Analyses for total cyclopropenoid fatty acid content of cottonseed oil andSterculia foetida oil by the gas-liquid chromatographic and hydrobromic acid titration procedures showed good agreement. Replicate analyses of a sample ofSterculia foetida oil for malvalic and sterculic acid gave coefficients of variation of 6.04% and 1.17%, respectively.     

Studies on the fatty acid composition of crayfish lipids

The fatty acid composition of carcass and exoskeleton lipids was determined for the freshwater crayfishOrconectes rusticus. Lipid fractions were isolated by column and thin-layer chromatography. Fatty acid methyl esters and alcohol acetates were then prepared and analyzed by gas-liquid chromatography. Peak identities were established from retention time data for methyl esters, hydrogenated methyl esters, and saturated, monoene, diene, and polyene methyl esters separated as acetoxy-mercuri-methoxy derivatives. Minor component acids were estimated from their relative compositions in these fractions. Presented at the symposium honoring J. B. Brown, AOCS meeting in Chicago, 1964.