Enzymatic Synthesis of Refined Olive Oil‐Based Structured Lipid Containing Omega ‐3 and ‐6 Fatty Acids for Potential Application in Infant Formula

Structured lipids (SLs) containing palmitic, docosahexaenoic (DHA), and gamma‐linolenic (GLA) acids were produced using refined olive oil, tripalmitin, and ethyl esters of DHA single cell oil and GLA ethyl esters. Immobilized Lipozyme TL IM lipase was used as the biocatalyst. The SLs were characterized for fatty acid profile, triacylglycerol (TAG) molecular species, solid fat content, oxidative stability index, and melting and crystallization profiles and compared to physical blend of substrates, extracted fat from commercial infant formula (IFF), and milk fat. 49.28 mol% of palmitic acid was found at the sn‐2 position of SL TAG and total DHA and GLA composition were 0.73 and 5.00 mol%, respectively. The total oleic acid content was 36.13 mol% which was very close to the 30.49% present in commercial IFF. Comparable solid fat content profiles were also found between SLs and IFF. The SLs produced have potential for use in infant formulas.     

Production of malic and succinic acids by sugar-tolerant yeast <Emphasis Type="Italic">Zygosaccharomyces rouxii</Emphasis>

Zygosaccharomyces rouxii V19 was grown in YPG medium (yeast extract, 0.5%, peptone, 1.0%, glucose, 10%). Fermented broth was purified through a series of ion-exchange columns and ODS column and the purified sample was TMS-esterified. Malic and succinic acids were identified with GC-MS analysis. The yeast was cultivated under various cultural conditions and quantitative determination of the organic acids was carried out with HPLC on Shodex column. Glucose concentration of 30%, initial pH 5.0, and 25 °C incubation temperature were the optimum conditions. Inclusion of glutamic, malic, and succinic acid precursors in the medium increased the production of malic acid. On the other hand, only addition of malic acid enhanced the production of succinic acid. Maximum amount of malic acid produced was 74.9 g/L (32.8% yield, based on glucose consumption) in the medium with 0.5% glutamic acid supplement, and that of succinic acid was 7.7 g/L (8.1% yield) when 0.3% malic acid was added in the medium.     

HPLC–DAD–ESI–MS Analysis of Phenolic Compounds During Ripening in Exocarp and Mesocarp of Tomato Fruit

Identification of phenolic compounds was done by means of liquid chromatography (HPLC) coupled to mass spectrometry (MS) using the electrospray ionization interface (ESI). Quantification of phenolic compounds was carried out by using HPLC with diode array detector (DAD) in exocarp and mesocarp of tomato fruit at 6 different ripeness stages (mature‐green, breakers, turning, pink, light‐red, and red). Several phenolic compounds were identified including chlorogenic acid, caffeic acid, p‐coumaric acid, ferulic acid, and rutin and some combined phenolic acids were tentatively identified, mainly glycosides, such as caffeoyl hexose I, caffeoyl hexose II, caffeoylquinic acid isomer, dicaffeoylquinic acid, p‐coumaroyl hexose I, p‐coumaroyl hexose II, feruloyl hexose I, feruloyl hexose II, siringyl hexose, and caffeoyl deoxyhexose hexose. Fruit exocarp had higher quantities of total soluble phenolics (TSP) compared to mesocarp. During ripening, TSP increased in both exocarp and mesocarp, mainly in exocarp. While rutin increased, chlorogenic acid decreased in both tissues: exocarp and mesocarp.     

Manipulation of Omega‐3 PUFAs in Lamb: Phenotypic and Genotypic Views

A number of studies have shown that dietary omega‐6 and omega‐3 long‐chain fatty acids can be incorporated into muscle tissue of ruminants despite the biohydrogenation of dietary fatty acids in the rumen. The main focus of this review is on eicosapentaenoic (20:5n‐3) and docosahexaenoic (22:6n‐3) fatty acids because health authorities around the world consider the sum of these fatty acids as the basis of classifying a food as a source or good source of omega‐3 polyunsaturated fatty acids (PUFAs). A high proportion of polyunsaturated fatty acids are hydrogenated in the rumen, leading to a higher concentration of 18:0, but some escapes the rumen to be absorbed intact by the small intestine. Feeding strategies for ruminants have been successfully applied to increase the absorption of PUFAs in the small intestine and therefore to increase the levels of PUFAs in muscle tissue. Protected fats and algae are strong candidates to improve the nutritional value of red meat in ruminants in terms of health‐claimable omega‐3 fatty acids. Efforts to understand the genetic basis of fatty acid metabolism have been underway. The knowledge of the main genes which control the output of omega‐3 fatty acids is still lacking, but gene expression studies have helped to explain the deposition of these acids in muscle, liver, and subcutaneous fat.     

α‐Eleostearic acid is more effectively metabolized into conjugated linoleic acid than punicic acid in mice

BACKGROUND: The objective of this study was to investigate the metabolism of α‐eleostearic acid (α‐ESA, cis9,trans11,trans13‐18:3) and punicic acid (PA, cis9,trans11,cis13‐18:3) and to compare the relative conversion efficiency of these fatty acids into conjugated linoleic acids (CLAs) in mice. RESULTS: Twenty‐four male ICR mice were fed either a control diet or one of two experimental diets supplemented with 10 g kg^?1α‐ESA or PA in the form of triacylglycerols for 6 weeks. The accumulation of PA in all tissues examined was significantly higher than α‐ESA; in both groups it was found that cis9,trans11‐conjugated linoleic acid (cis9,trans11‐18:2) was detected in all tissues examined. The relative conversion rate of α‐ESA into cis9,trans11‐18:2 was significantly higher than that of PA. The highest conversion rate of α‐ESA was found in adipose tissue (91.8%), spleen (91.4%) and kidney (90.7%), and the lowest in the heart (84.6%). The highest conversion rate of PA occurred in the liver (76.2%) and the lowest occurred in the heart (54.5%). CONCLUSION: The present results indicate that both α‐ESA and PA are effectively metabolized into cis9,trans11‐18:2 in mice. These conjugated dietary fatty acids might be useful sources of CLAs in tissues owing to the natural abundance of α‐ESA and PA in some seeds. Copyright © 2009 Society of Chemical Industry     

Simultaneous Determination of Mono‐, Di‐, and Trihydroxyoctadecenoic Acids in Beer and Wort

Monohydroxy, dihydroxy‐, and trihydroxyoctadecenoic acids in beer and wort were simultaneously determined using gas chromatography after a solid extraction method. These three acids were detected at ppm levels in the wort. The monohydroxyoctadecenoic acids were not detected after wort boiling, but the dihydroxy‐ and trihydroxyoctadecenoic acids were transferred through wort boiling, fermentation and lagering into the finished beer. During the mashing using a laboratory mash bath, they gradually increased to about twice the levels those at mashing‐in. The amounts of dihydroxyoctadecenoic acid and trihydroxyoctadecenoic acid in commercial beer samples varied from 0.6 to 1.6 ppm and 6 to 15 ppm, respectively.     

Phytochemical and biological investigation of <Emphasis Type="Italic">Stevia rebaudiana</Emphasis> Bertoni; 1-labdane-type diterpene

Five labdane diterpenoids, austroinulin, iso-austroinulin, sterebin E, sterebin E acetate, and sterebin A acetate, along with hydrocarbons, aliphatic alcohols, β-amyrin, β-sitosterol and stigmasterol were isolated from the chloroform soluble fraction of the methanol extract of Stevia rebaudiana leaves. Chlorogenic and caffeic acids were isolated from the EtOAc fraction. All the isolated compounds were identified using spectral tools. The chloroform and methanol extracts proved significant anti-inflammatory effect and caused marked inhibition of carrageenan-induced paw oedema in rats.     

Determination of short chain volatile fatty acids in silages from artichoke and orange by‐products by capillary gas chromatography

A simple, rapid and sensitive capillary gas chromatographic method was investigated to determine volatile fatty acids (VFA) in juice from silage made from artichoke and orange byproducts. The procedure uses a capillary column fused‐silica, 30 m×0.25 mm×0.25 mm ID and coated with FFAP‐TR. Centrifuged samples can be injected directly after lowering the pH to 1 and using a simple deproteinisation method. No adsorption, tailing or ghost phenomena occured. Separate analyses of VFA are quick and reliable. The average duration of an analyses is 7 min. The concentration, not only of the major acids, such as acetic acid, but also of the minor fermentation products such as butyric acid can be determined. The retention times of the products of fermentation and the extraction reagents were sufficiently different to avoid interference problems. © 1999 Society of Chemical Industry     

Concentration of n‐3 polyunsaturated fatty acids in cholesterol‐reduced cod‐liver oil by lipases

This study was conducted to elucidate the effects of different lipases originated from Candida rugosa (CR), porcine pancreas (PP) and Aspergillus niger (AN) on the degree of hydrolysis (DH) in cholesterol‐reduced cod‐liver oil (87.5%) and evaluate the changes in n‐3 polyunsaturated fatty acid concentrations in the oil hydrolysed by the lipases. The lipase‐catalysed hydrolysis of cholesterol‐reduced cod‐liver oil was performed at 37 °C for 8 h. Among all the lipase samples studied, DH in the oil after lipase‐catalysed hydrolysis followed the decreasing order: CR lipase (70.01%) > PP lipase (26.18%) > AN lipase (18.57%). Triacylglycerol levels in the oil hydrolysed by all the lipases studied decreased, while mono‐ and diacylglycerol levels increased during lipase‐catalysed hydrolysis. The eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) concentrations in cholesterol‐reduced cod‐liver oil hydrolysed by the CR lipase were remarkably higher than those by the PP or AN lipase. Thus, it is suggested in this study that the CR lipase appears to be most suitable for producing and n‐3 polyunsaturated fatty acids including EPA and DHA concentrates from cholesterol‐reduced cod‐liver oil.     

Stability Analysis of Zinc Oxide‐Nanoencapsulated Conjugated Linoleic Acid and Gamma‐Linolenic Acid

ABSTRACT: Conjugated linoleic acid (CLA) and gamma‐linolenic acid (GLA) were encapsulated with hydrated zinc oxide nanoparticles in an effort to improve their time and thermal stability. Encapsulated and nonencapsulated CLA and GLA were stored at 20, 30, 40, and 50 °C for 49 d. At various time points, encapsulated CLA and GLA were extracted, methylated, and analyzed using GC‐FID. Both encapsulated CLA and control CLA were stable when stored at 20, 30, and 40 °C for up to 49 d. However, control CLA was 100% degraded after 28 d at 50 °C, whereas encapsulated CLA was stable at 50 °C for 49 d. Similarly, both encapsulated GLA and control GLA were stable when stored at 20 °C for 49 d, but nonencapsulated GLA was 92% degraded after 49 d at 30 °C; encapsulated GLA was stable at 30 °C. Therefore, nanoencapsulation improves the time and temperature stability of CLA and GLA.