Elevated tissue status of omega-3 fatty acids protects against age-related telomere attrition in fat-1 transgenic mice.

BACKGROUND & AIMS: Leukocyte telomere length (LTL) is a biomarker of aging that may be influenced by dietary factors. Omega-3 fatty acids (n-3 FA) have been suggested to affect LTL. However, research on this effect has been inconclusive. The aim of the study was to test the hypothesis about the positive effect of n-3 FA on LTL. METHODS: Fat-1 transgenic mice, which can convert omega-6 fatty acids (n-6 FA) to n-3 FA and have elevated levels of endogenous n-3 FA in their tissues, were used to study the effects of n-3 FA on LTL at different ages. Blood samples from 10-month-old wild-type (WT) mice (n = 10) and fat-1 mice (n = 10) and 3-month-old WT mice (n = 5) and fat-1 mice (n = 5) were used to measure relative and absolute LTL. The levels of proteins critical for telomere maintenance were examined by Western blot analysis. RESULTS: Fat-1 transgenic mice had longer leukocyte telomeres than their WT siblings, suggesting a slower rate of age-related telomere shortening in fat-1 mice. In animals aged 10 months, the LTL was significantly longer in fat-1 than in WT mice (mean ± SEM; relative LTL: WT = 1.00 ± 0.09 vs. fat-1: 1.25 ± 0.05, P = 0.031; absolute LTL: WT = 64.41 ± 6.50 vs. fat-1: 78.53 ± 3.86, P = 0.048). The difference in LTL observed in three-month-old mice was insignificant, however the mean LTL was still longer in fat-1 mice than in the WT mice. Fat-1 mice also had abundant levels of two shelterin proteins: TRF1 (27%, P = 0.028) and TRF2 (47%, P = 0.040) (telomeric repeat binding factor 1 and 2) compared to WT animals. CONCLUSION: This study, for the first time in a unique animal model free of dietary confounders, has demonstrated that increased levels of n-3 FA in tissues can reduce telomere attrition. The data presented indicate the possibility of using omega-3 fatty acids to reduce accelerated telomere attrition and, consequently, counteract premature aging and reduce the risk of age-related diseases.

The Influence of the Apple Vinegar Marination Process on the Technological, Microbiological and Sensory Quality of Organic Smoked Pork Hams.

The effect of marinating pork hams in apple vinegar on the technological, microbiological, and sensory quality was verified. Three variants of pork hams were produced: S1-ham with curing salt, without apple vinegar; S2-ham with curing salt and 5% apple vinegar; S3-ham with salt and 5% apple vinegar. The tests were carried out immediately after production, after 7 and 14 days of storage. The products did not differ significantly in their chemical composition, salt content, fatty acid composition, and water activity (p > 0.05). During storage, a significant increase in the cholesterol content was observed (64.88-72.38 mg/100 g of the product). The lowest levels of nitrites and nitrates were recorded for treatment S3 (<0.10 and 4.73 mg/kg of product, respectively). The samples with the addition of apple vinegar (S2 and S3) were characterized by a lower pH value, higher oxidation-reduction potential, and TBARS (thiobarbituric acid reactive substances). Hams S3 were significantly brighter (L* 68.89) and less red (a* 12.98). All of the tested pork hams were characterized by very good microbiological quality (total number of microorganisms, number of lactic acid bacteria, number of acetic bacteria, number or presence of pathogenic bacteria). Significantly the lowest TVC (total viable counts) was found in the ham S3 (2.29 log CFU/g after 14 days). The S3 hams during storage were characterized by greater juiciness (6.94 c.u.) and overall quality (7.88 c.u.), but a lower intensity of smell and taste than the cured ham (S1). To sum up, it is possible to produce pork hams without the addition of curing salt, using natural apple vinegar as a marinade. Apple vinegar has a positive effect on the storage stability of the products, without losing their sensory properties.

The effect of the use of Limosilactobacillus fermentum S8 isolated from organic acid whey on nitrosyl pigment concentration and the colour formation of uncured cooked meat products.

This paper studies the application of Limosilactobacillus fermentum S8 from organic whey in meat processing and investigation the effect of bacteria on the concentration of nitrosyl pigments, colour formation, physicochemical characteristics and microbiological quality of uncured cooked meat products. 3 canned meat batters' were produced: control with salt and sodium nitrite (100 mg/ kg), treatment with salt, treatment with salt and L. fermentum S8 (107 cfu/g), then the cans were stored and cooked. The tests were carried out after production, 32 and 56 days of cold storage. It was shown that the use of L. fermentum in the processing of uncured meat caused the increase concentration of nitrosyl pigments and redness (a*) in the products after cooking. The addition of bacteria had a significant impact on the lowering pH value and the redox potential of the cooked products. The product from L. fermentum was characterized by a similar microbiological quality as compared to the traditionally cured and non-cured products (P < 0.05).

The Effect of Feeding Chicken and Geese Broilers with Different Cereals on the Fatty Acids Profile in Meat.

The research was conducted on the effect of bird broilers fed with different hybrid rye doses on the fatty acids profile in muscle. The first experiment was performed on 3 geese broilers groups fed with hybrid rye, oats or hybrid rye and oats mix in proportion 1:1. No effect of the hybrid rye feeding of geese on the SFA level in meat was observed, but the MUFA level was significantly higher and PUFA level and n-6/n-3 PUFA ratio were significantly lower than in geese fed with oats. The second experiment was performed on 3 chicken broiler groups fed with mix of corn, wheat, soybean meal and rapeseed oil (control group), and fed with an addition of 10% or 20% hybrid rye in diet (experimental groups). No effect of hybrid rye feeding of chicken broilers on the meat quality and SFA level was observed. However, the MUFA level was higher and the PUFA level and n-6/n-3 PUFA ratio were lower in meat of chicken broilers fed with hybrid rye. In conclusion hybrid rye is a healthy ingredient in the diet of studied birds and may be used up to 20% in chicken broilers and 50% in the diets of geese. A 100% hybrid rye in geese diet caused lower final body weight.

The Influence of Acid Whey on the Lipid Composition and Oxidative Stability of Organic Uncured Fermented Bacon after Production and during Chilling Storage.

The aim of this research was to evaluate the effect of acid whey on changes in the fatty acid profile, oxidative stability, physico-chemical parameters, and microbiological and sensory quality of traditional organic uncured fermented Polish bacon after production and during chilling storage. Three different treatments of fermented bacon were produced: C-control bacon with a nitrite curing mixture; T-bacon with a nitrate curing mixture; and AW-bacon with acid whey and NaCl. The acid whey used in the production of uncured fermented pork bacon positively changed the sensorial characteristics, directly after the ripening process, and had a positive effect in terms of a decrease in the pH of the product. All of the fermented bacon treatments in general were of good microbiological quality. A higher lactic acid bacteria (LAB) level was observed in the AW treatment after the fermentation process, and the bacteria number did not change during storage, whereas in the C and T treatments, the LAB level increased during storage (p < 0.05). The application of acid whey did not limit the formation of secondary oxidation products (TBARS) during bacon ripening (1.68 mg MDA kg-1), but had a reduced value during storage time (0.73 mg MDA kg-1). The highest polyunsaturated fatty acid (PUFA) levels, after ripening and after four weeks of refrigerated storage, were found in the C treatment. In the AW treatment, it was found that the PUFA level increased; likewise, the content of n-3 and n-6 fatty acids increased, while saturated fatty acids (SFAs) decreased during storage (p < 0.05). The opposite tendency was observed in the C treatment. After four weeks of storage, the PUFA/SFA ratio was the lowest in the nitrate treatment, and higher values of the PUFA/SFA ratio were obtained in the acid whey and nitrite treatment (p < 0.05).

Application of Silver Ion High-Performance Liquid Chromatography for Quantitative Analysis of Selected n-3 and n-6 PUFA in Oil Supplements.

The aim of this study was to develop a simple method for simultaneous determination of selected cis/cis PUFA-LNA (18:2), ALA (18:3), GLA (18:3), EPA (20:5), and DHA (22:6) by silver ion high-performance liquid chromatography coupled to a diode array detector (Ag-HPLC-DAD). The separation was performed on three Luna SCX Silver Loaded columns connected in series maintained at 10 °C with isocratic elution by 1% acetonitrile in n-hexane. The applied chromatographic system allowed a baseline separation of standard mixture of n-3 and n-6 fatty acid methyl esters containing LNA, DHA, and EPA and partial separation of ALA and GLA positional isomers. The method was validated by means of linearity, precision, stability, and recovery. Limits of detection (LOD) for considered PUFA standard solutions ranged from 0.27 to 0.43 mg L(-1). The developed method was used to evaluate of n-3 and n-6 fatty acids contents in plant and fish softgel oil capsules, results were compared with reference GC-FID based method.