Reino R. Linko

Gas-liqui chromatographic analysis of 2,4-dinitrophenyl-hydrazones of carbonyl compounds

Abstract Fifteen carbonyl compounds that are known to be flavor components have beenanalyzed as their 2,4-dinitrophenylhydrazones by gas-liquid chromatography on a 2% SE-30 column both isothermally at 232° and with a linear temperature program at a rate of 4°/min from 200 to 270° and on a 12% F-60 column at 225°. The detectors employed were a hydrogen flame ionization detector and an electron capture detector. Mixtures of the 2,4-dinitrophenylhydrazones can be successfully resolved on both columns although derivatives of compounds such as propanal, propenal and acetone with equal numbers of carbon atoms overlap. Some of the 2,4-dinitrophenylhydrazones gave rise to double peaks in gas-liquid chromatography owing mainly to the influence of the solvent. Peaks which were only slightly asymmetric were obtained when ethyl acetate was the solvent. The sensitivity was of the order of nanograms when the flame ionization detector was employed and five-hundred times greater when the electron capture detector was employed.

Comparison of the fatty acids in Baltic herring and available plankton feed

Triglycerides and phospholipids dominate in Baltic herring flesh lipids throughout the plankton growth season though at the same time plankton species and their lipids vary considerably. Wax esters and fatty alcohols do not exist in significant amounts in Baltic herring flesh or plankton. Saturated fatty acids exist in equal proportions in herring and plankton lipids whereas monoenoic acids are more dominant in herring and polyunsaturated acids in plankton lipids, respectively. The component alkyl chains are similar in both fish and plankton fatty acids, thus suggesting the planktonic origin. During the period of abundant availability of plankton the changes in the fatty acids of the herring depot fat are related to the changes in the plankton lipid composition.

Fatty acids of long chain length in baltic herring lipids

The component fatty acids with carbon numbers exceeding 22 in flesh lipids of Baltic herring caught in May and September 1967 in the Turku archipelago have been studied. The total lipid content of the flesh of the herring was 3.5% on average in May and 7.2% on average in September. The fatty acids in the lipids were converted to methyl esters which were resolved and analyzed by urea adduct fractionation, thin layer chromatography and programmed temperature gas liquid chromatography (GLC). The lipids of the herring caught in May were found to contain 15 fatty acids with 24–32 carbon atoms, whereas the lipids of the herring caught in September were found to contain only nine fatty acids with 24–28 carbon atoms. The differences are probably due to nutritional factors. The long chain fatty acids in the lipids of the herring caught in September were isolated by preparative GLC and their structures were studied by UV spectroscopy before and after alkali isomerization, by IR spectroscopy and by GLC of their ozonization products. The identified acids were tetracosanoic, 15-tetracosenoic, 12,15,18,21-tetracosatetraenoic, 9,12,15,18,21-tetracosapentaenoic, 6,9,12,15,18,21-tetracosahexaenoic, 17-hexacosenoic, 11,14,17,20,23-hexacosapentaenoic, 8,11,14,17,20,23-hexacosahexaenoic and 4,7,10,13,16,19,22-octacosaheptaenoic acids. The proportion of the fatty acids containing over 22 carbon atoms in the lipids of fall herring is much higher than has been found earlier in the lipids of marine teleost fish; the reason may be due at least partly to differences in analytical methods.

Fatty acids in the roe lipids of common food fishes

The roe lipid fatty acids of Baltic herring, roach, perch, burbot and rainbow trout were quantitatively studied by capillary-GLC. The composition of roe fatty acids remain fairly stable during the fish maturation. The fatty acid profiles are very similar in various fish roes though differences exist in the relative amounts of individual components. On average perch and burbot have longer chain lengths and higher unsaturation degrees in their roe fatty acids compared to the other species. Variations in the fatty acids can be related to the roe lipid compositions and apparently also to the diet of the parent fish.

Comparison of lipid and fatty acid composition in vendace (Coregonus albula L.) and available plankton feed

Abstract 1. 1. The food of vendace in Lake Pyhajarvi (SW Finland) consisted mainly of cladocerans and copepods throughout the sampling period from May to October. 2. 2. The content of triacylglycerols and polar lipids of vendace flesh, varied seasonally, in accordance with the total lipids. Triacylglycerols dominated in vendace flesh, while these and polar lipids occurred in nearly equal proportions in composite plankton. In vendace gut, the share of polar lipids decreased markedly. 3. 3. Plankton and vendace flesh total lipids were composed of the same fatty acids. Their relative amounts varied, especially in polyenoic acids and in the ratio of ω-6 and ω-3 polyenoics. 4. 4. The fatty acid composition of fish flesh lipids remained fairly similar throughout the whole sampling period with a slight seasonal variation of some fatty acids occurring in plankton total lipids.

Environmental toxins in Finnish Wildlife. A study on time trends of residue contents in fish during 1973–1978

Abstract The O.E.C.D. monitoring Wildlife Sampling and Analysis Programme 1973–1975 has been extended at national level in Finland to 1978 by analysing chlorinated hydrocarbon residues in fish at two marine and two freshwater environments and mercury at the latter two freshwater environments. Statistical treatment of the analysis results gave significant decreasing trends in most cases of PCB and DDT residues but in mercury levels no significant change was detected.

Volatile monocarbonyl compounds of carrot roots at various stages of maturity

ZusammenfassungDie leichtflüchtigen Carbonylverbindungen der Karotten Varietät „Feonia Hunderup S-64” wurden in verschiedenen Stufen der Reife als 2,4-DNPH mit der kombinierten DC-GC-MS-Methode analysiert. Dreiundzwanzig verschiedene Carbonylverbindungen wurden nachgewiesen. Von diesen sind Undecanal, 2-Butenal, Methylbutenal, 2-Pentanon, 6-Methyl-5-hepten-2-on und 5-Methylfurfural noch nicht in Karotten aufgefunden worden. Während des Reifens nahm der Gehalt an Acetaldehyd und Aceton bedeutend zu. Der Gehalt an Methylbutenal verminderte sich.SummaryVolatile carbonyl compounds of carrot varietyFeonia Hunderup S-64 at various stages of maturity were analysed as their 2,4-DNPHs by a combined TLC-GLC-MS method. Twenty-three different carbonyl compounds were identified, of which undecanal, buten-2-al, methylbutenal, pentan-2-one, 6-methyl-5-hepten-2-one and 5-methylfurfural have not previously been found in carrot. During maturation the content of acetaldehyde and acetone increased significantly, while that of methylbutenal decreased.

Lipids and fatty acids in plankton from the finnish coastal waters of the Baltic sea

Abstract 1. 1. In the Finnish coastal waters phytoplanktonic diatoms dominate in early summer, changing to zooplanktonic Rotatoria in June and later to Copepoda. 2. 2. The lipid contents in plankton varied from 0.2 to 2.5% wet weight or from 1.9 to 17.0% dry weight, respectively. 3. 3. Triglycerides and polar lipids together dominated in phytoplankton while polar lipids alone were the major lipid in zooplankton. Exceptionally high proportions of free fatty acids existed in most samples whereas wax esters were detected only as minor components. 4. 4. Over two thirds of the fatty acids in phytoplankton were composed of C 16 acids, whereas palmitic acid together with polyenoic C 20 and C 22 acids dominated in zooplankton. 5. 5. Monoenoic C 20 and C 22 acids, often abundant in copepods, were found only in minor amounts in this study.

Volatile monocarbonyl compounds of arctic bramble (Rubus arcticus L.) at various stages of ripeness

SummaryVolatile carbonyl compounds of arctic brambles at various stages of ripeness were analyzed as their 2,4-DNPHs by a combined TLC-GLC-MS method. Twenty-one different carbonyl compounds could be identified. During the ripening process the content of most carbonyl compounds increased, the largest changes occuring in the amounts of acetaldehyde, pentenal, acetone, acetonn and diacetyl but the content of hexenal decreased.ZusammenfassungDie leichtflüchtigen Carbonylverbindungen der Brombeere wurden in verschiedenen Stufen der Reife als 2,4-DNPH mit der kombinierten DC-GC-MS-Methode analysiert. 21 verschiedene Carbonylverbindungen wurden entdeckt. Während des Reifens vermehrte sich die Quantität der meisten Carbonylverbindungen; die größten Veränderungen geschahen in der Menge des Acetaldehyds, Pentenals, Acetons, Acetons und Diacetyls. Der Gehalt an Hexenal verminderte sich.

Identification of keto acids in arctic bramble,Rubus arcticus L. as methyl esters of their 2,4-dinitrophenylhydrazones

The major keto acids in arctic bramble,Rubus arcticus L. were investigated. The acids were isolated with anionic and cationic ion-exchange resins, converted to 2,4-dinitrophenylhydrazones, and purified with an Al2O3 column. The derivatives were separated on a silica gel G thin-layer plate and esterified with methanol-HCl and the methyl esters of the keto acid 2,4-dinitrophenylhydrazones formed were analyzed on an OV-1-glass capillary gas-liquid chromatography column and with mass spectrometry. 2-Oxoglutaric, pyruvic, oxaloacetic, and glyoxylic acids were identified. The mass spectra of the derivatives are presented.