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The content of malondialdehyde (MDA), considered as a product of oxidation of lipids harmful to health in commercial infant formulae (IF) and follow-on formulae (FF) (N=13), human milk (N=7), cow’s milk (N=7), soybean oil and rapeseed oil was studied. The MDA content was confirmed to be high, ranging from 40.50±13.77 to 89.60±15.26 μg/100 mL infant milk formulae, compared to 19.35±5.14 μg/100 mL in human milk on average. Such a great difference between MDA contents of commercially available formulae and human milk is accounted for imperfection of different technologies of manufacturing IF and FF. The major quantity of MDA is formed during the production, packing in the air and storage of IF and FF. It is suggested that the content of MDA should be labeled. The authors’ suggestion is that the maximum allowable tolerance of MDA should not exceed 48.0 μg MDA/ 100 mL liquid IF and FF.
Changes in the composition of fatty acids (FA) were determined in lipid extracts isolated from developing ovaries containing ovules and developing seeds of Echium vulgare L. The samples were collected successively over 20 days beginning with the first day after flowering. The contents of the n-6 FA family members, i.e., γ-linolenic (GLA) (C18:3) and linoleic (LA) (C18:2) acids changed in a parallel manner and reached the maximum of 13.9% and 24%, respectively, on the 12th day, after which they fell systematically down to 8.6% and 18.2%, respectively, on the 20th day after flowering. Starting with day 13, the content of α-linolenic acid (ALA) (C18:3 n-3) begins to grow intensively, from 24.2% to 39.3% on the 20th day after flowering. The increase in the content of stearidonic acid (SDA) (C18:4 n-3), up to 10.5% on the 20th day after flowering, occurred steadily as the seeds developed, and was independent of the changes in the content of GLA and LA. The pattern of changes in the content of SDA, GLA, LA and ALA during the development of seeds, and the occurrence of SDA in the seed oil of other plants, demonstrate that the biosynthesis of SDA in the seeds is critically dependent on the presence of ALA. The above condition indicates that SDA biosynthesis in the seeds of Echium vulgare follows the scheme LA → simultaneous, competitive, action of Δ6 and Δ15 desaturases, leading to the formation of GLA and ALA, respectively, and then ALA (Δ6 des) → SDA. The biosynthesis according to the scheme: GLA (Δ15 des) → SDA is highly unlikely.
Kwasy tłuszczowe zawierające układ trzech sprzężonych wiązań podwójnych TCFA (trienoic conjugated fatty acids) są produktami oksydacji lipidów szkodliwymi dla zdrowia niemowląt i jako takie mogą stanowić znacznik stopnia zaawansowania utlenienia tłuszczu mleka początkowego (infant formulae IF) i następnego (follow-on formulae FF). Zbadano zawartość TCFA w tłuszczu wolnym i w tłuszczu związanym IF i FF. Liczbowo zawartość TCFA wyrażono umownie jako parametr K [%] będący stosunkiem absorbancji układu trzech sprzężonych wiązań podwójnych kwasów tłuszczowych (analityczna długość fali 268 nm) do absorbancji charakterystycznej dla grup karbonylowych triacylogliceroli (218 nm). Próbkę odniesienia stanowił tłuszcz dojrzałego mleka ludzkiego. Parametr K tłuszczu mleka ludzkiego wynosił maksymalnie 0,60 ±0,03% (N=9), podczas gdy rozpiętość K tłuszczu badanych IF i FF zawierała się w granicach: minimalnie 4,49 ±0,27%, maksymalnie 12,40 ±0,73% w zależności od producenta IF i FF (5 różnych producentów, łącznie 17 produktów). Rozbieżności w zaawansowaniu stopnia utlenienia lipidów mają związek z jakością i ilością dodawanych olejów roślinnych oraz z zastosowaną technologią produkcji IF i FF. Mając na uwadze szkodliwość dla zdrowia produktów oksydacji lipidów, zwłaszcza dla niemowląt i małych dzieci, zasugerowano wprowadzenie limitu parametru K tłuszczu IF i FF na maksymalnie 6%. Spośród 17 badanych produktów 22% spełniało te wymagania.
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63%
The determination of the furosine (FUR) indicator of the Maillard reaction in commercial infant formulae (IF), follow-on formulae (FF), human milk (N=10) and raw cow milk (N=7) was performed using high performance liquid chromatography with ultraviolet detection (HPLC/UV). A high FUR content was confirmed that ranged from 1320±102.2 to 1550.9±166.5 mg/100 g protein in infant formulae IF and from 931.9±153.8 to 1156.7±104.5 mg/100 g protein in follow-on formulae FF (human milk – at the average below 6 mg/100 g protein). Such a significant difference between FUR values of commercially available formulas is accounted for imperfection of different technologies of manufacturing IF and FF. In dairy products damage caused by heat treatment could be greater as a result of manufacturing processes and storage conditions. Furosine content was used in order to calculate the concentration of blocked lysine. In infant formulas IF’s the blocked lysine levels were found to range from 19.6 to 34% of total lysine. Taking into consideration harmful for health, toxic products of Mallard reaction, the content of FUR should be labelled. In the Authors’ opinion, the content of furosine tolerance should make compromise between that what is theoretical demanded and that what is practical reached (fresh milk powder for all purposes – about 120 mg FUR/100 g protein, FF of producer C – 930 mg FUR/100 g protein). The authors’ suggestion is that the maximum allowable tolerance of FUR should not exceed 700 mg/100 g protein of IF and FF.
These was examined the oils from seeds or fruits obtained from nine plants growing in their natural environment or cultivated under the conditions of temperate zone: Ligustrum vulgare L., Mahonia aquifolium Nutt., Mirabilis jalapa L., Myrrhis odorala L., Papaver rhoeas L., Robinia pseudoacacia L., Rosa canina L., Saponaria officinalis L., Viburnum opulus L. These was determined the content of oils and fatty acids both in quantity and quality. The highest content of oil was found in P. rhoeas seeds (37.5%). It was also rich in EFAs (78.72%). The some high amount of EFAs was determined in the oil extracted from R. canina fruits (73.33%) and R. pseudoacacia seeds (80.68%). The oil obtained from the fruits of M. odorata had the highest amount of oleinic acid (82.12%), amount of oil in this material was 12.29%.
Polyunsaturated fatty acids (PUFAs, LA and ALA) are not synthesized in mammals in the absence of their essential fatty acid precursors. However, hibernating animals and animals sleeping through the winter need sufficiently high amounts of these acids. The Eurasian badger does not hibernate, but sleeps over winter. In the autumn the body weight of adult badgers increases even twofold, since they put on fat before the winter. Fat is deposited primarily in the subcutaneous layer of adipose tissue, and much less commonly in the muscles, liver and around the intestines. The percentage composition of fatty acids (Saturated fatty acids-SFAs, monounsaturated fatty acids-MUFAs, PUFAs) is different in particular types of tissue. The lipids isolated from depot adipose tissues (suet, subcutaneous, perirenal, periintestinal fat) are dominated by monounsaturated fatty acids (on average 41.25%), followed by saturated fatty acids (33.53%). Polyun­saturated FAs have the lowest proportion in this groups of tissues, on average 17.75% of total FAs. On the other hand, liver lipids contain over 44% PUFAs. The fatty acid composition of lipids in badgers tissue includes considerable quantities of essential unsaturated n-6 and n-3 fatty acids of great pharmacological significance.
Our paper presents a qualitative analysis of particular lipid classes (phospholipids, triacylglycerols, cholesterol, free fatty acids) isolated from the tissues of raccoon dogs harvested in northeastern Poland. In all examined tissues (except for the liver) the dominant group of lipids were triacylglycerols. The amounts of lipids representing the other classes depended on the kind of tissue from which the fat was isolated. The concentration of phospholipids was 0.7% in subcutaneous tissue and 41.7% in the liver, cholesterol content ranged between 0.6 and 4.8%, while the amount of fee fatty acids varied from 0.3% in subcutaneous tissue to 5.1% in the liver. Fat deposited in different body parts of the raccoon dog is generally uniform with regard to FA composition. Particular attention should be paid to the presence of trans-octadecenoic acids in the tissues of raccoon dogs, since these acids are commonly found in ruminants and herbivores.
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