Thiobarbituric Reactive Substances Research Articles

Effect of an Olive Vegetation Water Phenolic Extract on the Physico-Chemical, Microbiological and Sensory Traits of Shrimp (Parapenaeus longirostris) during the Shelf-Life.

The aim of this study was to evaluate the effects of phenolic extract derived from olive vegetation water (PEOVW) in deep-water rose shrimps (Parapenaeus longirostris) at the day of packaging (D0) and after three (D3), six (D6) and eight (D8) days of refrigerated storage. Freshly caught shrimps were randomly divided into four groups: the phenolic extract (PE) group (2 g/L of phenols); the sulfites (S) group (0.5% sodium metabisulfite solution); the phenolic extract + sulfites (PE + S) group (0.25% sodium metabisulfite solution with 1 g/L of phenols), and the control (CTRL) group (tap water). Concerning color coordinates, there were no variations either between groups or over time, while it is important to highlight that phenolic extract (PE group) led to a significant reduction in total volatile basic nitrogen (TVB-N; p < 0.001) and thiobarbituric reactive substances (TBARS; p < 0.001) values. Furthermore, PE also had a relevant effect in reducing bacterial counts and decreasing the microbial development. Finally, as concerns melanosis, the effect of phenolic extract alone was marginal, but when combined with half a dose of sodium metabisulfite, it was as effective as the shrimps treated with only sodium metabisulfite in delaying black spots (p < 0.05). These results are very promising with a view to commercializing additive-free shrimps.

Oral administration of potato peel extract affects serum blood metabolites, liver function and ameliorating oxidative stress induced in rabbits exposed to cold stress

This study investigated the effect of potato peel extract (PPE), orally administrated to rabbits, on serum blood metabolites and ameliorating oxidative stress induced by cold stress under Egyptian winter conditions. Twenty-four bucks grouped into three treatments (8 animals per group) were used for the experiment. The animals received 1.5 ml of water orally, containing 0 (PPE0), 25 (PPE25) or 50 (PPE50) mg PPE/kg live weight. Bucks were randomly assigned into three homogenous equal groups according to the level of PPE. Treatments were applied to each animal every two days over a period of three months including one month as an adaptation period. At the 8th week of the experiment, blood samples were collected from each buck and at the end of the experiment, bucks were slaughtered, and some organs were collected and weighed. The PPE improved (p < 0.05) blood total protein, albumin, globulin and glucose. The blood concentration of total lipid, cholesterol, triglyceride, low density lipoprotein and very low-density lipoprotein (were increased (p < 0.02) in PPE rabbits. Furthermore, PPE extract doses decreased (p < 0.001) oxidant thiobarbituric reactive substance (TBARS) in both blood and liver. Other liver and blood antioxidant system enzymes such as catalase, glutathione peroxidase, and superoxide dismutase were improved (p < 0.005) by PPE supplementation. Overall, oral administration of PPE up to 50 mg/kg live weight can have positive effects on rabbit health under cold stress.

Influence of Frozen Storage on Properties of Rohu and Pangas Protein Isolates Obtained from Its Processing Waste

ABSTRACT The aim of this investigation was to study the influence of freezing and frozen storage on properties of protein isolates obtained from rohu and pangas processing waste through pH shift processing (pH 2.0 and 13.0). Quality changes were measured for a period of 3 months at −18°C. Increase in storage period decreased the myoglobin content, pigment content, and cooking yield (p < .05). Increase in frozen storage period increased thiobarbituric reactive substances to a range of 4.09–4.98 mg MAD kg−1. L* values of isolates decreased with the advancement of storage time (p < .05). Quality of protein gels was also affected by freezing and frozen storage. At the end of the storage period, pangas acid, pangas alkali, rohu acid, and rohu alkali isolate gels had folding test scores of 2.0, 1.0, 1.0, and 1.0, respectively. Gel strength values also decreased significantly from 1131.36, 1001.80, 847.57, and 746.88 g cm to 325.63, 226.77, 224.98, and 203.95 g cm for pangas acid, pangas alkali, rohu acid, and rohu alkali isolates, respectively. The effect of frozen storage was found to be high on pangas alkali isolate, which was evident by the drastic fall of G’ and G” values (p < .05).

Valorisation of black mulberry and grape seeds: Chemical characterization and bioactive potential

Grape (Vitis vinifera L. var. Albariño) and mulberry (Morus nigra L.) seeds pomace were characterized in terms of tocopherols, organic acids, phenolic compounds and bioactive properties. Higher contents of tocopherols (28 ± 1 mg/100 g fw) were obtained in mulberry, whilst grape seeds were richer in organic acids (79 ± 4 mg/100 g fw). The phenolic analysis of hydroethanolic extracts characterised grape seeds by catechin oligomers (36.0 ± 0.3 mg/g) and mulberry seeds by ellagic acid derivatives (3.14 ± 0.02 mg/g). Both exhibited high antimicrobial activity against multiresistant Staphylococcus aureus MIC = 5 mg/mL) and no cytotoxicity against carcinogenic and non-tumour primary liver (PLP) cells. Mulberry seeds revealed the strongest inhibition (p < 0.05) against thiobarbituric reactive substances (IC50 = 23 ± 2 µg/mL) and oxidative haemolysis (IC50 at 60 min = 46.0 ± 0.8 µg/mL). Both seed by-products could be exploited for the developing of antioxidant-rich ingredients with health benefits for industrial application.

The lysine derivative aminoadipic acid, a biomarker of protein oxidation and diabetes-risk, induces production of reactive oxygen species and impairs trypsin secretion in mouse pancreatic acinar cells

We have examined the effects of α-aminoadipic acid, an oxidized derivative from the amino acid lysine, on the physiology of mouse pancreatic acinar cells. Changes in intracellular free-Ca2+ concentration, the generation of reactive oxygen species, the levels of carbonyls and thiobarbituric-reactive substances, cellular metabolic activity and trypsin secretion were studied. Stimulation of mouse pancreatic cells with cholecystokinin (1 nM) evoked a transient increase in [Ca2+]i. In the presence of α-amoniadipic acid increases in [Ca2+]i were observed. In the presence of the compound, cholecystokinin induced a Ca2+ response that was smaller compared with that observed when cholecystokinin was applied alone. Stimulation of cells with cholecystokinin in the absence of Ca2+ in the extracellular medium abolished further mobilization of Ca2+ by α-aminoadipic acid. In addition, potential pro-oxidant conditions, reflected as increases in ROS generation, oxidation of proteins and lipids, were noted in the presence of α-aminoadipic acid. Finally, the compound impaired trypsin secretion induced by the secretagogue cholecystokinin. We conclude that the oxidized derivative from the amino acid lysine induces pro-oxidative conditions and the impairment of enzyme secretion in pancreatic acinar cells. α-aminoadipic acid thus creates a situation that could potentially lead to disorders in the physiology of the pancreas.

Effects of Prunus cerasus L. Seeds and Juice on Liver Steatosis in an Animal Model of Diet-Induced Obesity.

The accumulation of adipose tissue increases the risk of several diseases. The fruits-intake, containing phytochemicals, is inversely correlated with their development. This study evaluated the effects of anthocyanin-rich tart cherries in diet-induced obese (DIO) rats. DIO rats were exposed to a high-fat diet with the supplementation of tart cherry seeds powder (DS) and seed powder plus juice (DJS). After 17 weeks, the DIO rats showed an increase of body weight, glycaemia, insulin, and systolic blood pressure. In the DS and DJS groups, there was a decrease of systolic blood pressure, glycaemia, triglycerides, and thiobarbituric reactive substances in the serum. In the DJS rats, computed tomography revealed a decrease in the spleen-to-liver attenuation ratio. Indeed, sections of the DIO rats presented hepatic injury characterized by steatosis, which was lower in the supplemented groups. In the liver of the DIO compared with rats fed with a standard diet (CHOW), a down-regulation of the GRP94 protein expression and a reduction of LC3- II/LC3-I ratio were found, indicating endoplasmic reticulum stress and impaired autophagy flux. Interestingly, tart cherry supplementation enhanced both unfolded protein response (UPR) and autophagy. This study suggests that tart cherry supplementation, although it did not reduce body weight in the DIO rats, prevented its related risk factors and liver steatosis.

Anserine Reverses Exercise-Induced Oxidative Stress and Preserves Cellular Homeostasis in Healthy Men.

The study tested whether anserine (beta-alanyl-3-methyl-l-histidine), the active ingredient of chicken essence affects exercise-induced oxidative stress, cell integrity, and haematology biomarkers. In a randomized placebo-controlled repeated-measures design, ten healthy men ingested anserine in either a low dose (ANS-LD) 15 mg·kg−1·bw−1, high dose (ANS-HD) 30 mg·kg−1·bw−1, or placebo (PLA), following an exercise challenge (time to exhaustion), on three separate occasions. Anserine supplementation increased superoxide dismutase (SOD) by 50% (p < 0.001, effect size d = 0.8 for both ANS-LD and ANS-HD), and preserved catalase (CAT) activity suggesting an improved antioxidant activity. However, both ANS-LD and ANS-HD elevated glutathione disulfide (GSSG), (both p < 0.001, main treatment effect), and consequently lowered the glutathione to glutathione disulfide (GSH/GSSG) ratio compared with PLA (p < 0.01, main treatment effect), without significant effects on thiobarbituric acid active reactive substances (TBARS). Exercise-induced cell damage biomarkers of glutamic-oxaloacetic transaminase (GOT) and myoglobin were unaffected by anserine. There were slight but significant elevations in glutamate pyruvate transaminase (GPT) and creatine kinase isoenzyme (CKMB), especially in ANS-HD (p < 0.05) compared with ANS-LD or PLA. Haematological biomarkers were largely unaffected by anserine, its dose, and without interaction with post exercise time-course. However, compared with ANS-LD and PLA, ANS-HD increased the mean cell volume (MCV), and decreased the mean corpuscular haemoglobin concentration (MCHC) (p < 0.001). Anserine preserves cellular homoeostasis through enhanced antioxidant activity and protects cell integrity in healthy men, which is important for chronic disease prevention. However, anserine temporal elevated exercise-induced cell-damage, together with enhanced antioxidant activity and haematological responses suggest an augmented exercise-induced adaptative response and recovery.

In Vitro Antioxidant Properties of Berry Leaves and Their Inhibitory Effect on Lipid Peroxidation of Thigh Meat from Broiler Chickens

AbstractThe present study is designed to evaluate the antioxidant compounds from bilberry, cranberry, and raspberry leaves in connection with their radical scavenging activities, and their potential in inhibiting the lipid peroxidation of thigh meat from broiler chickens. For this purpose, plant extracts are analyzed regarding the content in bioactive compounds, antioxidant properties analysis including 1,1‐diphenyl‐2‐picrylhydrazyl, superoxide, hydrogen peroxide, and hydroxyl radical‐scavenging activities. Lipid peroxidation is induced by an Fe+3/ascorbic acid system and the inhibitory effects of plants extracts are assessed using thiobarbituric reactive substances (TBARS) as biomarkers for quantifying lipid oxidation in meat. The overview of the analyzed antioxidant compounds shows that cranberry leaves present the highest concentrations of vitamin E, β‐carotene, lutein and zeaxanthin, and polyphenols and a total antioxidant capacity with 52% higher than bilberry and 360% than raspberry. Bilberry leaves extract shows the strongest effect (p &lt; 0.0001) in inhibiting meat lipid peroxidation.Practical Applications: The results demonstrate the positive effect of the selected berry leaves in the oxidative stability of broiler chicken meat under in vitro conditions, and may be suggested as an alternative source of natural antioxidants for animal nutrition, with benefits in inhibiting and delaying oxidation, and also enhancing the nutritional value of meat.

Application of natural antioxidant extract from guava leaves (Psidium guajava L.) in fresh pork sausage

The current study was conducted to determine the antioxidant efficacy of guava leaf extract (3000 to 6000 ppm on fat basis) in fresh pork sausage, compared with negative control (CON) and 200 ppm butylated hydroxytoluene (BHT), for 0, 1, 4, 7, 10, and 14 d at 4 °C. The extract provided a total antioxidant capacity of 1505 μmol trolox equivalence/g. From d 4, the extract at 5000 and 6000 ppm provided greater (P < .05) antioxidant capacity than the CON and was either similar (P > .05) or greater (P < .05) than BHT. From d 4, the sausage formulated with 4000 to 6000 ppm of guava leaf extract had less conjugated dienes, lower peroxide and acidic values, less thiobarbituric reactive substances value, and better color (P < .05) than the CON and did not differ from BHT (P > .05). Guava leaf extract at 4000 ppm or greater is effective in preventing oxidation in fresh pork sausage.

In vitro and in vivo inhibitory effects of Carica papaya seed on α-amylase and α-glucosidase enzymes

The present study was aimed to investigate the in vitro and in vivo inhibitory effects of Carica papaya seeds on α-amylase and α-glucosidase enzymes, as this is known to be an antidiabetic mechanism. Analysis of the extracts of the seeds for phytochemicals revealed the presence of a significant amount of saponins, alkaloids, flavonoids, phenols, terpenoids, and steroids. The seed extracts of Carica papaya exhibited good antioxidant capacity using 2, 2-diphenyl-1-picryl hydroxyl (DPPH), thiobarbituric reactive substance (TBARS) and ferric reducing antioxidant power (FRAP) method. The results of the inhibitory studies of the extracts revealed that the hexane extract followed by the ethyl acetate extract was the most potent inhibitor of α-amylase and α-glucosidase enzyme when compared to other extracts using their IC50 values. In the animal study, different doses (250, 500 and 1000 mg/kg/body weight) of the extracts of Carica papaya seed were administered orally for 120 min, to normal and streptozotocin-induced diabetic rats, and were compared with acarbose 100 mg/kg/body weight and control group for the effect on postprandial hyperglycemia. The extract of ethyl acetate (at doses of 250, 500 and 1000 mg/kg/body weight) significantly reduced postprandial glucose levels in these animals. The characterization of hexane and ethyl acetate extracts by GC-MS analysis revealed 20 bioactive compounds while the FTIR analysis confirmed the presence of this functional groups: -C=C, -C-Cl, -C-O, -O-H, -CH, -C=O, -C=C=C, -N=C=S, -O=C=O and -N-H in Carica papaya seed extracts. It was concluded that the inhibition of α-amylase and α-glucosidase enzymes and the prevention of oxidative stress in postprandial hyperglycemia could be some of the possible mechanisms by which they exert their anti-diabetic properties.

Antioxidant performances of corn gluten meal and DDGS protein hydrolysates in food, pet food, and feed systems

Protein hydrolysates from corn gluten meal (CGM) and distillers’- dried grains with solubles (DDGS) were prepared with Neutrase and Alcalase, and the antioxidant activity of those hydrolysates in bulk oils, ground pork, canine pet food, and pig feed were evaluated by measuring oxidation stability based on peroxide value (PV) and thiobarbituric reactive substances (TBARS) value. Alcalase-hydrolyzed CGM (CPH-A) and Neutrase-hydrolyzed CGM (CPH–N) had stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than Alcalase-hydrolyzed DDGS (DPH-A) and Neutrase-hydrolyzed DDGS (DPH-N). The CPH-N showed better prevention on lipid oxidation in both corn oil and fish oil compared with other corn antioxidants. The best oxidation prevention in ground meat was observed with 2 g/kg of CPH-N. Lipid oxidation in pet food containing 2% DPH-A was efficiently retarded by 37.8% reduction at the end of the incubation, and TBARS value of pig feed containing 2% CPH-N was reduced the most compared with other treatments. However, there was no significant difference in growth performance and plasma antioxidant concentration between broilers fed with DDGS or Alcalase-treated DDGS. Overall, CGM and DDGS protein hydrolysates could potentially be used as naturally derived antioxidant in food, pet food, and feed systems with good protection efficiency for lipid oxidation to improve product storage stability.

Effects of dietary myrcene administration on antioxidant gene responses in common carp ( Cyprinus carpio ), exposed to copper sulphate

In the present study, common carp (Cyprinus carpio) were fed with diet supplemented with 0% (M0) or 0.5% (M0.5) myrcene for 6 week and exposed to ambient copper (0.2 mg/L) for further 2 weeks. Gene expressions of superoxide dismutase (sod), catalase (cat), glutathione peroxidase (gpx), glutathione reductase (gr) and glutathione S-transferase (gst) were assayed in the fish brain and kidney, and thiobarbituric reactive substance (TBARS) levels were determined in blood plasma. The results showed that there was no significant difference in TBARS levels between the M0 and M0.5 treatments, before the copper exposure; however, the M0 had significantly higher TBARS levels compared to the M0.5, after the copper exposure. The antioxidant genes showed different patterns in the fish brain and kidney. The genes were up-regulated in the fish brain by dietary myrcene and copper exposure. However, in the fish kidney, the M0.5 treatment showed no change in sod, cat, gpx before and after the copper exposure. The results suggest that myrcene is capable to induce antioxidant enzymes that prepare the fish for a further oxidative condition (i.e. copper exposure). Dietary myrcene at 0.5% level is suggested for common carp before treatment with copper sulphate.

MiADMSA minimizes arsenic induced bone degeneration in Sprague Dawley rats

Arsenic considered as one of the most hazardous chemical while arsenic poisoning is also one of the serious medical issues worldwide. Long term arsenic exposure is associated with bone degeneration. The exact mechanism involving arsenic induced bone degeneration remains unclear but, plentiful literature suggested that oxidative/nitrosative stress caused by generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) is one of the leading causes.Various treatment strategies are available for bone degeneration however, the suitable treatment for arsenic induced bone degeneration still lacks. In the current investigation, we evaluated the efficacy of chelation against arsenic induced bone degeneration in experimental rats. Male Sprague Dawley rats were exposed to sodium arsenite and dimethylarsinic acid (DMA) (50 ppm) for 18 weeks. After arsenic exposure, animals were treated with Monoisoamyl dimercaptosuccinic acid (MiADMSA) for three course of treatment (50 mg/kg, p.o., once daily for 5 days) with an interval of one week between two courses of treatment. MiADMSA minimizes the bone degeneration through reduction of oxidative stress (Reactive Oxygen Species, Reactive Nitrogen Species, and thiobarbituric reactive substances), alteration of antioxidant status (rGSH, Superoxide dismutase, Catalase) which led to the depletion in the levels of inflammatory markers like TNFα and IL-1β and alteration in the bone remodelling biomarkers like ALP, RANKL, and Runx2. It can be concluded from this study that MiADMSA could be an effective therapeutic strategy against arsenic induced bone degeneration and the possible mechanism could be the chelation of arsenic accompanied by the reduction in oxidative stress and inflammation.

Involvement of Cholinergic and Redox Impairments in Insecticidal Properties of Essential Oils from Fertility Tree and Horseradish Tree Leaves in Fruit Fly (Drosophila melanogaster).

This study reports the biological activity of essential oils from fertility tree and horseradish tree leaves, and the mechanisms by which these oils promote insecticidal activity using Drosophila melanogaster as a model organism. Adult D. melanogaster were exposed to these essential oils at a final concentration of 10 µL/g for 24 hours. The exposure of flies to the essential oil resulted in significant decrease in their survival and fecundity. In addition, the essential oils produced significant reduction in acetylcholinesterase activity and induced oxidative stress in the flies as evidenced by an increase in reactive oxygen species, thiol and thiobarbituric reactive substance levels, as well as catalase activity. The essential oils were also characterized by gas chromatography coupled with mass spectrometry. Constituents such as terpenoids, Bis (2-ethylhexyl) phthalate, benzeneacetaldehyde, phytol, octadecane, 9,12-octadecadienoic acid (Z,Z)- methyl ester, heneicosane, eicosane and others were characterized. Therefore, our results point out to the potential application of fertility tree and horseradish tree leaf essential oils as natural alternatives to synthetic insecticides in agricultural and pest control practices, especially against dipterans.

Effect of Dietaryn‐3Source on Rabbit Male Reproduction

In the last two decades, the human sperm count linearly decreased in Western countries. Health problems, lifestyle, pollutants, and dietary behaviours are considered as the main risk factors, and the unbalance of dietary n‐6/n‐3 fatty acids is one of the most relevant. The aim of the present research is to study the effect of different dietary sources of n‐3 polyunsaturated fatty acids (PUFA) on reproductive traits using rabbit buck as the animal model. Fifteen rabbit bucks were assigned to three experimental groups: the control group, the FLAX group fed 10% extruded flaxseed, and the FISH group fed 3.5% fish oil for 110 days (50-day adaptation and 60-day experimental periods). Semen samples were collected weekly, whereas blood was collected every two weeks for the analytical determination of semen traits, oxidative status, fatty acid profiles, isoprostanes, neuroprostanes, and the immunocytochemistry of docosahexaenoic acid (DHA) and eicosapentaenoic (EPA) acid. At the end of the trial, the rabbits were killed and the testes were removed and stored for the analysis of fatty acid profile and immunocytochemistry. Results showed that dietary administration of n‐3 PUFA improved the track speed of the sperm and increased the n‐3 long-chain PUFA mainly confined in the sperm tail. Seminal plasma increased the thiobarbituric reactive substances (TBARs) by three times in the groups fed supplemental n‐3, whereas the F2-isoprotanes (F2-IsoPs) and F4-neuroprostanes (F4-NeuroPs) were lower and higher, respectively, in both supplemented groups than in the control. The testes and sperm showed a higher DHA and EPA distribution in rabbits from the n‐3 supplemented groups compared with the control. In conclusion, supplemental dietary n‐3 PUFA improved sperm motion traits and resulted in an enrichment of membrane fatty acid in the sperm and testes of the rabbits. However, such an increased amount of PUFA negatively affected the sperm oxidative status, which was mainly correlated with the generation of F4-NeuroPs with respect to F2-IsoPs. Accordingly, the latter cannot be considered a good marker of oxidation when diets rich in n‐3 PUFA are provided.

Lipid oxidation inhibition capacity of plant extracts and powders in a processed meat model system

A meat model system was used for screening lipid oxidation inhibiting capacity of diverse horticultural plant materials. In the model, heme-containing sarcoplasmic proteins from the meat water-phase were homogenized with linoleic acid and thiobarbituric reactive substances (TBARS) were measured. 23 Plant materials were investigated at three high (50, 100, and 200 ppm) concentrations and five plant extracts were tested at three low (5, 10, and 20 ppm) concentrations over time. In the high concentration sets, summer savory freeze-dried powder, beetroot leaves extracted with 50% ethanol, and an olive polyphenol powder extracted from wastewater, inhibited oxidation the most effectively. After two weeks and at 200 ppm concentration, oxidation was reduced to 17.2%, 16.6% and 13.5% of the blank sample with no added antioxidants respectively. In the low concentration set, spray dried rhubarb juice inhibited oxidation the most after two weeks at 5 ppm where oxidation was reduced to 68.3% of the blank sample with no added antioxidants.

Correlation Among Ground Beef Lipid Content, Color, and Lipid Oxidation Over a 7-Day Simulated Retail Display Period

ObjectivesGround beef is more susceptible to lipid oxidation compared to whole muscle beef cuts. This is due to its smaller particle size and greater surface area, which makes the meat products more prone to be exposed to various environmental factors during production. The objective of this study was to determine the relationships among ground beef lipid content, instrumental color, visual discoloration, and lipid oxidation over a 7d simulated retail display period.Materials and MethodsBeef inside rounds (IMPS #168) from the right sides of steer carcasses (n = 63) were collected from a commercial processing facility and delivered to the U of Guelph Meat Science Laboratory for further analyses. Each inside round was trimmed of all subcutaneous fat and connective tissue, and then fabricated into ground beef patties (113 g/patty) at two targeted fat addition levels (no added fat and 25%). Lean ground beef (no added fat) was made by grinding cubes of inside round muscle through a Sirman Master 90 Y12 meat grinder (Sirman USA, Franklin Park, IL). Regular ground beef (25% added fat) was made by grinding cubed round muscle with an additional 25% subcutaneous fat that originated from the rib primal of the same carcass. For the simulated retail shelf life study, 2 crust frozen patties (crust frozen for 1 h to improve packaging ability) were placed on a Styrofoam meat tray with a soaker pad and overwrapped with PVC film. In total, there were 4 trays of patties per ID (2 trays/targeted fat level). Trays were placed under two LED lights (52 W, 1850 lumens, color temperature of 4000K, 1612.5 to 2152 lux) at 4°C and the locations on shelves were changed every 24 h. Minolta L*, a*, b* color and subjective surface discoloration were evaluated every 24 h for 7 d. Lipid peroxidation of patties before and after the retail display was estimated using thiobarbituric reactive substances (TBARS; mg MDA/g fat). Lipid content of patties was quantified using Soxhlet extraction with petroleum ether. Summary statistics and Pearson correlation coefficients were determined using the PROC CORR procedure of SAS. Correlations were regarded as weak at r &lt; |0.35|, moderate at |0.36| ≤ r ≤ |0.67|, and strong at r ≥ |0.68|.ResultsLipid content in the 126 ground beef samples evaluated in this study ranged from 3.47% to 30.43% (16.30% ± 6.18%). A moderate and significant correlation was observed between lipid content and change in TBARS values (r = –0.59, P &lt; 0.0001). Similarly, an increase in lipid content is moderately correlated with a decrease in a* values (r = –0.58, P &lt; 0.0001) and an increase in surface discoloration after a 7d display period (r = 0.53, P &lt; 0.0001). Δ TBARS values was weakly correlated with Δ L* (r = 0.24, P &lt; 0.01), Δ a* (r = 0.11, P = 0.25), and visual discoloration (r = –0.16, P = 0.09). Finally, Δ a* was strongly correlated with surface discoloration values at d7 (r = –0.76, P &lt; 0.0001).ConclusionAn increase of lipid content in ground beef had a moderate association with decreased redness, greater surface discoloration, and less change in lipid oxidation over a 7d simulated retail display period. Color values were not great predictors of lipid oxidation values and trained technicians often equated visual discoloration in beef to a deviation from the desired cherry red color.

Evaluation of vegetables and fish oils for the attenuation of diabetes complications

The present study was accomplished to examine and compare the effect of specific antioxidant-rich oils on hyperglycemia, dyslipidemia, renal function markers and oxidative renal damage in diabetic rats for four weeks. Papaya (P), olive (O), fenugreek (Fe), bitter gourd (B) and fish (Fi) oils were used for this purpose. Streptozotocin (STZ) was injected intraperitoneally in a single dose to induce diabetes. All oils were given orally at a dose of 3g/kg for four weeks in respective group after induction of diabetes. After treatment with oils, blood was collected, and their kidneys were stored. The level of fasting blood glucose (FBG), glycated hemoglobin (HbA1c), total cholesterol (TC), triglycerides (TG), low-density lipoprotein-cholesterol (LDL-C) and very low-density lipoprotein-cholesterol (VLDL-C) increased while amylase and high-density lipoprotein cholesterol (HDL-C) level decreased in the diabetic rats. These changes were augmented by fenugreek, bitter gourd and olive oils treatment. Diabetic rats showed elevated renal function markers in serum, including, serum creatinine (Scr), blood urea nitrogen (BUN) and alkaline phosphatase (ALP), which were restrained significantly by fenugreek and bitter gourd oil treatment. Moreover, fenugreek and bitter gourd oils treatment significantly modulated the level of thiobarbituric reactive substances (TBARS), malonaldehyde (MDA) and catalase (CAT) in the kidney of diabetic rats. The histopathological examination also showed the protective effect of these oils. The study suggests that vegetable oils are effective in reducing hyperglycemia, dyslipidemia and renal damage related to the side effects of diabetes. Thus they may have therapeutic value for preventing diabetes side effects and may be included in oil diet treatment synergically. Thus, our data suggest that oils as potent antidiabetic agent and beneficial in the control of diabetes-related abnormalities such as hyperglycemia, dyslipidemia and renal damage of STZ induced rat model of type 2 diabetes. Our study also supports the suggestion that synergistic possibilities exist concerning the use of these oils in the treatment of diabetes mellitus.

Lipid Oxidation Inhibition Capacity of 11 Plant Materials and Extracts Evaluated in Highly Oxidised Cooked Meatballs

The underlying mechanism(s) behind the potential carcinogenicity of processed meat is a popular research subject of which the lipid oxidation is a common suspect. Different formulations and cooking parameters of a processed meat product were evaluated for their capacity to induce lipid oxidation. Meatballs made of beef or pork, containing different concentrations of fat (10 or 20 g 100 g−1), salt (2 or 4 g 100 g−1), subjected to differing cooking types (pan or deep frying), and storage times (1, 7, and 14 days), were evaluated using thiobarbituric reactive substances (TBARS). The deep-fried meatball type most susceptible to oxidation was used as the model meat product for testing the lipid oxidation inhibiting capacity of 11 plant materials and extracts, in two concentrations (100 and 200 mg kg−1 gallic acid equivalent (GAE)), measured after 14 days of storage using TBARS. Summer savory lyophilized powder was the most efficient plant material, lowering lipid oxidation to 13.8% and 21.8% at the 200 and 100 mg kg−1 concentration, respectively, followed by a sea buckthorn leaf extract, lowering lipid oxidation to 22.9% at 100 mg kg−1, compared to the meatball without added antioxidants. The lipid oxidation was thus successfully reduced using these natural antioxidants.

Long-Chain n-3 PUFA Content and n-6/n-3 PUFA Ratio in Mammal, Poultry, and Fish Muscles Largely Explain Differential Protein and Lipid Oxidation Profiles Following In Vitro Gastrointestinal Digestion.

Muscle food characteristics (fatty acid profile, heme-Fe, intrinsic antioxidants) that relate to the formation of (patho)physiological oxidation products during gastrointestinal digestion are investigated. Muscles (n = 33) from 18 mammal, poultry, and fish species, of which some are mixed with lard to standardize their fatty acid profile, are digested in vitro. Lipid oxidation is assessed by thiobarbituric reactive substances (TBARS), n-3 PUFA derivative 4-hydroxy-2-hexenal and propanal, n-6 PUFA derivative 4-hydroxy-2-nonenal and hexanal, and protein oxidation by carbonylation. Digests of n-3 PUFA-rich fish demonstrated the highest n-3 PUFA oxidation, whereas digests of various poultry and rabbit muscles showed highest n-6 PUFA oxidation, which correlated significantly with the n-6/n-3 PUFA ratio. Without lard addition, lipid oxidation is significantly higher in chicken and pork loin digests versus beef and deer digests, whereas the opposite occurred when these muscles are mixed with lard. Protein carbonylation correlates significantly with levels of TBARS and the sum of hydroxy-alkenals in digests. The n-6/n-3 PUFA ratio correlates well with the 4-hydroxy-2-nonenal/4-hydroxy-2-hexenal ratio in digests. Muscular fatty acid profiles largely explain type and extent of lipid and protein oxidation during gastrointestinal digestion. Red meat only stimulates oxidation when digested with specific fat sources.