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The aim of the study was to investigate the occurrence and formation of peroxygenase catalysed non-volatile oxidised fatty acids (NVOFAs), especially epoxy and hydroxy fatty acids, which potentially provide off-flavours in oat. A method based on extraction of NVOFAs using accelerated solvent extraction and analysis by UHPLC-ELSD/MS was developed. Hydroxy and epoxy fatty acids from oleic and linoleic acids were present as major NVOFAs in non-heat treated (NHT) oat products, and the contents increased markedly during storage. In a controlled storage experiment, NVOFA contents in NHT oat flours increased to 1700-2000 µg/g, whereas in heat-treated samples, only to 200-400 µg/g. Epoxy fatty acids seemed to be the first products that occurred, followed by hydroxy fatty acids and minor NVOFAs. The formation of NVOFAs was related to lipase catalysed lipid hydrolysis and the formation of volatile lipid oxidation products. Inactivation of lipid degrading enzymes is crucial to producing stable oat products., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The encapsulation of eugenol (E) by spray-drying using whey protein (WP) or soy lecithin (LE) and maltodextrin in combination with oleic acid (OA) and chitosan (CH) was analysed in order to obtain antioxidant and antimicrobial powders for food applications. Formulations with only WP or LE showed higher encapsulation efficiencies (EE) (95-98%) and antibacterial effect against E. coli and L. innocua due to their greater E load. Incorporation of OA or CH promoted lower EE, which negatively affected the antimicrobial and antioxidant activities of the powders. Furthermore, the addition of CH implied less thermal protection against the E losses. The eugenol release was not notably affected by pH or polarity of the food simulant, but the release rate significantly decreased when incorporating OA and CH. The E-LE formulations better retained the eugenol than E-WP powders when heated above 200 °C, this being relevant for the powder inclusion in thermally treated products., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Ethnopharmacological Relevance: Terminalia laxiflora Engl. & Diels, (Sudanese Arabic name: Darout الدروت) and Terminalia brownii Fresen (Sudanese Arabic name: Alshaf ألشاف) (Combretaceae) are used in Sudanese traditional folk medicine and in other African countries for treatment of infectious diseases, TB and its symptoms, such as cough, bronchitis and chest pain., Aim of Study: Because of the frequent use of T. laxiflora and T. brownii in African traditional medicine and due to the absence of studies regarding their antimycobacterial potential there was a need to screen extracts of T. laxiflora and T. brownii for their growth inhibitory potential and to study the chemical composition and compounds in growth inhibitory extracts., Materials and Methods: The plant species were collected in Sudan (Blue Nile Forest, Ed Damazin Forestry areas) and selected according to their uses in traditional medicine for the treatment of bacterial infections, including TB. Eighty extracts and fractions of the stem bark, stem wood, roots, leaves and fruits of T. laxiflora and T. brownii and nine pure compounds present in the active extracts were screened against Mycobacterium smegmatis ATCC 14468 using agar diffusion and microplate dilution methods. Inhibition zones and MIC values were estimated and compared to rifampicin. HPLC-UV/DAD, GC/MS and UHPLC/Q-TOF MS were employed to identify the compounds in the growth inhibitory extracts., Results: The roots of T. laxiflora and T. brownii gave the best antimycobacterial effects (IZ 22-27 mm) against Mycobacterium smegmatis. The lowest MIC of 625 µg/ml was observed for an acetone extract of the root of T. laxiflora followed by methanol and ethyl acetate extracts, both giving MIC values of 1250 µg/ml. Sephadex LH-20 column chromatography purification of T. brownii roots resulted in low MIC values of 62.5 µg/ml and 125 µg/ml for acetone and ethanol fractions, respectively, compared to 5000 µg/ml for the crude methanol extract. Methyl (S)-flavogallonate is suggested to be the main active compound in the Sephadex LH- 20 acetone fraction, while ellagic acid xyloside and methyl ellagic acid xyloside are suggested to give good antimycobacterial activity in the Sephadex LH-20 ethanol fraction. RP-18 TLC purifications of an ethyl acetate extract of T. laxiflora roots resulted in the enrichment of punicalagin in one of the fractions (Fr5). This fraction gave a five times smaller MIC (500 µg/ml) than the crude ethyl acetate extract (2500 µg/ml) and this improved activity is suggested to be mostly due to punicalagin. 1,18-octadec-9-ene-dioate, stigmast-4-en-3-one, 5α-stigmastan-3,6-dione, triacontanol, sitostenone and β-sitosterol were found in antimycobacterial hexane extracts of the stem bark of both studied species. Of these compounds, 1,18-octadec-9-ene-dioate, stigmast-4-en-3-one, 5α-stigmastan-3,6-dione, triacontanol, sitostenone have not been previously identified in T. brownii and T. laxiflora. Moreover, both plant species contained friedelin, betulinic acid, β-amyrine and two unknown oleanane-type triterpenoids. Of the listed compounds, friedelin, triacontanol and sitostenone gave a MIC of 250 µg/ml against M. smegmatis, whereas stigmasterol and β-sitosterol gave MIC values of 500 µg/ml., Conclusions: Our results show that T. laxiflora and T. brownii contain antimycobacterial compounds of diverse polarities and support the traditional uses of various parts of T. laxiflora and T.brownii as decoctions for treatment of tuberculosis. Further investigations are warranted to explore additional (new) antimycobacterial compounds in the active extracts of T. laxiflora and T. brownii., (Copyright © 2018. Published by Elsevier B.V.)

Lard from pork back fat was dry fractionated based on crystallization temperature, resulting in fractions with a ratio of saturated to unsaturated fatty acids of 1.10 and 0.61. Lean minced pork was mixed with the saturated and unsaturated fat fraction and stored in modified atmosphere (80% O 2 and 20% CO 2 ) at 5 °C for 2, 5, 7, 9, and 12 days under light to investigate the effect on oxidative stability of lipids and proteins. The saturated fat group developed higher TBARS values and lower levels of free thiol groups during storage, indicating that the unsaturated fat fraction in minced pork promoted increased oxidative stability of both lipids and proteins. A higher content of α-tocopherol in the unsaturated fat fraction suggests that the differences in oxidative stability is causatively linked to the balance between the fatty acid composition and content of antioxidants. The TBARS values and free thiol content were negatively correlated, suggesting a relationship between lipid and protein oxidation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The aim was to study lipase, lipoxygenase (LOX) and peroxygenase (POX) activities in oat and faba bean samples to be able to evaluate their potential in formation of lipid-derived off-flavours. Lipase and LOX activities were measured by spectroscopy, and POX activities via the formation of epoxides. An ultra-high performance liquid chromatography method was developed to study the formation of fatty acid epoxides. The epoxides of esters were measured by gas chromatography. Mass spectroscopy was used to verify the identity of the epoxides. Both oat and faba bean possessed high lipase activities. In faba bean, LOX catalysed the formation of hydroperoxides, whose break-down products are the likely cause of off-flavours. Since oat had low LOX activity, autoxidation is needed to initiate lipid oxidation. Oat had high POX activity, which is able to convert hydroperoxides to epoxy and hydroxy fatty acids that could contribute significantly to off-flavours. POX activity in the faba bean was low. Thus, in faba bean volatile lipid oxidation products could rapidly be formed by LOX, whereas in oat reactions are slower due to the need of autoxidation prior to further reactions., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The aglycones of vicine and convicine, divicine and isouramil, are the causative agents of favism and, therefore, should be analysed along with vicine and convicine in research seeking to eliminate them. This study investigated the stability of the aglycones produced by hydrolysis with β-glucosidase. Reversed-phase, high-performance liquid chromatography (HPLC) with UV detection was shown to be able to observe both aglycone formation and further reactions in isolated fractions and extract made from faba bean and in faba bean suspension. Divicine and isouramil were unstable and degraded almost completely in extract in 60min and completely in fractions in 120min at a pH of 5 at 37°C. Adding sodium ascorbate delayed degradation of divicine. Divicine was more stable at 20°C than at 37°C. Being able to show formation and degradation of the aglycones, the proposed method allows monitoring of the vicine and convicine detoxification process., (Copyright © 2016. Published by Elsevier Ltd.)

In food systems, lipid oxidation can cause oxidation of other molecules. This research for the first time investigated oxidative degradation of β-glucan induced by lipid oxidation using an oil-in-water emulsion system which simulated a multi-phased aqueous food system containing oil and β-glucan. Lipid oxidation was monitored using peroxide value and hexanal production while β-glucan degradation was evaluated by viscosity and molecular weight measurements. The study showed that while lipid oxidation proceeded, β-glucan degradation occurred. Emulsions containing β-glucan, oil and ferrous ion showed significant viscosity and molecular weight decrease after 1 week of oxidation at room temperature. Elevated temperature (40°C) enhanced the oxidation reactions causing higher viscosity drop. In addition, the presence of β-glucan appeared to retard the hexanal production in lipid oxidation. The study revealed that lipid oxidation may induce the degradation of β-glucan in aqueous food systems where β-glucan and lipids co-exist., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In this study, we present the difference in sterol composition of extracted steryl glycosides (SG) hydrolyzed by either enzymatic or acid hydrolysis. SG were analyzed from foods belonging to the plant families Cucurbitaceae (melon and pumpkin seeds) and Amaranthaceae (amaranth and beetroot), both of which are dominated by Δ(7)-sterols. Released sterols were quantified by gas chromatography with a flame ionization detector (GC-FID) and identified using gas chromatography/mass spectrometry (GC-MS). All Δ(7)-sterols identified (Δ(7)-stigmastenyl, spinasteryl, Δ(7)-campesteryl, Δ(7)-avenasteryl, poriferasta-7,25-dienyl and poriferasta-7,22,25-trienyl glucoside) underwent isomerization under acidic conditions and high temperature. Sterols with an ethylidene or methylidene side chain were found to form multiple artifacts. The artifact sterols coeluted with residues of incompletely isomerized Δ(7)-sterols, or Δ(5)-sterols if present, and could be identified as Δ(8(14))-sterols on the basis of relative retention time, and their MS spectra as trimethylsilyl (TMS) and acetate derivatives. For instance, SG from melon were composed of 66% Δ(7)-stigmastenol when enzymatic hydrolysis was performed, whereas with acid hydrolysis only 8% of Δ(7)-stigmastenol was determined. The artifact of Δ(7)-stigmastenol coeluted with residual non-isomerized spinasterol, demonstrating the high risk of misinterpretation of compositional data obtained after acid hydrolysis. Therefore, the accurate composition of SG from foods containing sterols with a double bond at C-7 can only be obtained by enzymatic hydrolysis or by direct analysis of the intact SG.

It has previously been shown that maternal nutrition affects the fetal environment, with consequences for the infant's health. From early pregnancy onwards participants here received a combination of dietary counseling and probiotics (Lactobacillus GG and Bifidobacterium lactis Bb12; n = 10), dietary counseling with placebo (n = 12), or placebo alone (n = 8). The major differences in placental fatty acids were attributable to a higher concentration of n-3 polyunsaturated fatty acids in both intervention arms than in controls. Further, dietary counseling with probiotics resulted in higher concentrations of linoleic (18:2n-6) and dihomo-gamma-linolenic acids (20:3n-6) compared with dietary counseling with placebo or controls.

Despite clinical evidence of the cholesterol-lowering effects of phytosterols, the exact mechanisms involved are still unclear. Displacement of cholesterol by phytosterols from mixed micelles, which is due to their greater hydrophobicity, is one of the hypotheses for the lumenal effects contributing to the reduction of intestinal cholesterol absorption. In this study a dynamic in vitro lipolysis method was used to examine the solubilization behavior of cholesterol and/or phytosterols during lipolysis to probe the efficacy of cholesterol displacement from mixed micelles by phytosterols. The effects of lipid chain length on sterol solubilization were studied by using microcrystalline suspensions containing 17% phytosterol or cholesterol, formulated in long-chain TG (LCT) and medium-chain TG (MCT). When digesting cholesterol-suspended in LCT, the entire cholesterol dose was incorporated into the micellar phase. For the cholesterol formulation suspended in MCT, 50.3% of the initial dose was recovered in the micelles. Under the respective conditions, we observed lower solubilization of phytosterols than of cholesterol (roughly fourfold). Only 25% of the initial phytosterol dose was solubilized from suspensions formulated with LCT, and 13% was solubilized from MCT formulations. Co-administration of phytosterol and cholesterol suspensions showed a significant reduction of cholesterol solubilization, particularly when dosed in MCT, with approximately 25% of the cholesterol dose solubilized. Insignificant amounts of cholesterol were displaced by phytosterols when cholesterol was presolubilized in the mixed micelles. The results show that, compared with LCT, mixed micelles containing MCT lipolysis products have a reduced solubilizing capacity for cholesterol, which adds to the effectiveness of the phytosterols in displacing cholesterol. This suggests potential benefits of using medium chain length lipids in cholesterol-lowering phytosterol products.

Background: Vitamin E may have immunomodulatory properties beyond its antioxidant function. The objective here was to assess the alpha- and gamma-tocopherol status and its correlation between atopic mothers and their infants., Methods: Mothers with atopic disease were recruited at the end of gestation and their infants were followed up. Serum samples from mothers and infants were collected at the infants' age of 1 month. Atopic dermatitis was diagnosed during the 1st year of life and skin prick tests were performed at 1 year., Results: Infants' serum gamma- and alpha-tocopherol to fat ratios were significantly correlated with maternal serum ratios (r=0.70, p<0.0001 and r=0.52, p=0.004, respectively). In infants the serum alpha-tocopherol/fat was higher and the gamma-tocopherol/fat ratio lower than in mothers. Serum tocopherol levels were not associated with skin prick test reactions or atopic dermatitis in the infants., Conclusions: Maternal tocopherol status determines that of the infant. Different tocopherol forms may have different serum levels and roles in the regulation of inflammatory diseases., (Copyright (c) 2005 S. Karger AG, Basel.)

Because of the positive health effects of phytosterols, phytosterol-enriched foods and foods containing elevated levels of natural phytosterols are being developed. Phytosterol contents in cereals are moderate, whereas their levels in the outer layers of the kernels are higher. The phytosterols in cereals are currently underutilized; thus, there is a need to create or identify processing fractions that are enriched in phytosterols. In this study, pearling of hulless barley and rye was investigated as a potential process to make fractions with higher levels of phytosterols. The grains were pearled with a laboratory-scale pearler to produce pearling fines and pearled grains. Lipids were extracted by accelerated solvent extraction, and nonpolar lipids were analyzed by normal-phase HPLC with ELSD and UV detection. Total sterol analyses were performed by GC. After a 90-s pearling, the amounts of pearling fines from hulless barley and rye were 14.6 and 20.1%, respectively, of the original kernel weights. During pearling, higher levels of phytosterols and other lipids were fractionated into the fines. The contents of free sterols and sterols esterified with FA in the fines were at least double those in the whole grains. Pearling fines of hulless barley and rye contained >2 mg/g phytosterol compounds, which makes them a good source of phytosterols and thus valuable raw materials for health-promoting foods.

Information on phyto-oestrogen intake in various populations has been scanty until now, primarily because data on the content of these compounds in foods were lacking. We report here on expansion of the Finnish National Food Composition Database (Fineli) with values for the plant lignans matairesinol and secoisolariciresinol and the isoflavones daidzein and genistein. The values, expressed as aglycones, were based on food analyses (mainly GC-MS) or imputed from analytical data for 180 foods for lignans and 160 foods for isoflavones; additionally, over 1000 values were derived from the recipe database of Fineli. Average intake of these phyto-oestrogens was calculated using food consumption data of the National Dietary Survey FINDIET 1997, which was carried out in a random sample of the adult population in five areas in Finland. The dietary data were collected by 24 h recall =2862). The mean lignan intake was 434 (standard deviation (SD) 1575) microg/d and the mean isoflavone intake was 788 (SD 673) microg/d. Women had a higher lignan density (microg lignans/MJ) in their diet than men (P<0.05). Men had a higher mean daily isoflavone intake, 902 (SD 368) microg, than women, 668 (SD 963) microg (P<0.05). The sources of lignans were many: seeds, cereals, fruit, berries and vegetables. The main sources of isoflavones appeared to be processed meat products/sausages containing soya as an ingredient, and legumes as such. The average intake of lignans and isoflavones in Finland seems to be low, but intake varies throughout the population.

Manufacturing of healthy wholegrain foods demands knowledge of process-induced changes in macro-, micro- and non-nutrients. The high content of dietary fibre is a challenge in relation to good product texture and sensory quality. The stability and bioavailability of bioactive compounds have a marked influence on the health effects of cereal foods. It was confirmed that sterols, folates, tocopherols and tocotrienols, alkylresorcinols, lignans, phenolic acids and total phenolics are concentrated in the bran layers of the rye grain, and are only present at low levels in the flour endosperm. The levels of folate and easily-extractable phenolic compounds increase in germination and sourdough baking, but there are negligible changes in the levels of sterols, lignans and alk(en)ylresorcinols. The levels of tocopherols and tocotrienols are reduced during the sourdough fermentation. In conclusion, many of the bioactive compounds in wholegrain rye are stable during food processing, and their levels can even be increased with suitable processing.

Plant sterols are subjected to oxidation when exposed to air and, especially, when heated at high temperatures. We developed a method to study thermo-oxidation of plant sterols. The method consisted of cold saponification, purification of oxides by solid-phase extraction and gas chromatography analysis. To compensate for losses during the procedure, an internal standard was added before saponification. The method showed good recovery of added cholesterol oxides, separation of plant sterol oxides and reproducibility in detecting thermo-oxidation products of stigmasterol and rapeseed oil. Based on this study, the major products are 7-hydroxy, 5,6-epoxy and 7-keto compounds and oxides are formed faster in bulk stigmasterol than in rapeseed oil.