| 1. |
- Gunnarsson, Gudjon, et al.
(författare)
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Inhibitory effect of known antioxidants and of press juice from herring (Clupea harengus) light muscle on the generation of free radicals in human monocytes
- 2006
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Ingår i: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 54:21, s. 8212-8221
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Tidskriftsartikel (refereegranskat)abstract
- Reactive oxygen species (ROS) can cause oxidative stress, which has been linked to various diseases. It has been suggested that antioxidant-rich foods can reduce such oxidative stress. However, the lack of suitable model systems to screen for in vivo effects of food-derived antioxidants has prevented a clear consensus in this area. In this study, the aim was to use a single-cell model system (human monocyte) to evaluate whether certain pure antioxidants and complex muscle extracts (herring light muscle press juice, PJ) could prevent ROS formation under in vivo like conditions. ROS were excreted from the monocytes upon stimulation with phorbol myristate acetate and were then detected as isoluminol-enhanced chemiluminescence (CL). Adding 2000 units of catalase and 50 units of superoxide dismutase to the monocytes model lowered the CL response by 35 and 86%, respectively. Ascorbate (14.1 mM) lowered the response by 99%, alpha-tocoperhol (188 microM) by 37%, and Trolox (50 microM) by almost 100%. Crude herring PJ gave a dose-dependent reduction in the CL response. At 10, 100, and 1000 times dilution, the PJ reduced the CL signal by 93, 60.5, and 10.6%. PJ fractionated into low molecular weight (LMW) (<1000 Da) and high molecular weight (>3500 Da) fractions decreased the CL response by 52.9 and 71.4%, respectively, at a 100-fold dilution. Evaluation of the PJ samples in the oxygen radical absorbance capacity test indicated that proteins may be the primary radical scavenging compounds of PJ, whereas the ROS-preventing effect obtained from the LMW fraction may also be attributed to other mechanisms. Thus, this study proved that the monocyte assay can be a useful tool for studying whether food-derived antioxidants can limit ROS production under physiologically relevant conditions. It also showed that herring contains numerous aqueous compounds demonstrating antioxidative effects in the monocyte model system.
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| 2. |
- Lindqvist, Helen, 1977, et al.
(författare)
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Influence of herring (Clupea harengus) and herring fractions on metabolic status in rats fed a high energy diet.
- 2009
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Ingår i: Acta physiologica (Oxford, England). - : Wiley. - 1748-1716 .- 1748-1708. ; 196:3, s. 303-14
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Tidskriftsartikel (refereegranskat)abstract
- AIM: Few dietary studies have looked beyond fish oil to explain the beneficial metabolic effects of a fish-containing diet. Our aim was to study whether addition of herring, or sub-fractions of herring, could counteract negative metabolic effects known to be induced by a high-fat, high-sugar diet. METHODS: Rats were given six different diets: standard pellets; high energy diet with chicken mince (HiE control); high energy diet with herring mince (HiE herring); and high energy diet with chicken mince and either herring oil (HiE herring oil), herring press juice, PJ (HiE PJ) or herring low molecular weight PJ (HiE LMW-PJ). Factors associated with the metabolic syndrome were measured. RESULTS: There were no differences in energy intake or body weight between the groups, but animals fed high energy diets had a higher body fat content compared with the pellet group, although not statistically significant in all groups. Mesenteric adipocyte size was smaller in the HiE herring oil group compared with the HiE control. Glucose clamp studies showed that, compared with the pellet group, the HiE control and HiE herring diets, but not the HiE herring oil diet, induced insulin resistance. Addition of herring or herring oil to the high energy diet decreased total cholesterol levels, triacylglycerols and the atherogenic index compared with the HiE control group. CONCLUSIONS: The results suggest that addition of herring or herring oil counteracts negative effects on blood lipids induced by a high energy diet. The lipid component of herring thus seems to be responsible for these beneficial effects.
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| 3. |
- Sannaveerappa, Thippeswamy, 1976
(författare)
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Antioxidative Properties of Herring (Clupea harengus) Press Juice in Food, In Vitro and In Vivo Model Systems
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Some species like herring (Clupea harengus) are currently under-utilized due to their small size, dark colour and susceptibility to lipid oxidation. Our hypothesis has been that the high susceptibility of herring to oxidation makes it well equipped with natural antioxidants, both fat and water soluble ones. The aim of this thesis has been to isolate the water soluble antioxidants in terms of a herring light muscle extract (press juice, PJ) and to test the capacity of this PJ to inhibit oxidation in different model systems ranging from food to in vivo conditions. Attempts were also made to identify the tentative compounds responsible for the antioxidative properties.Herring PJ was fractionated into low molecular weight (LMW; 1, 3.5, 50 kDa) fractions. Some samples were also heat treated (100 degree C, 10 min). The antioxidaitve properties of the PJ samples were tested and compared with pure antioxidants using a hemoglobin (Hb) containing washed cod mince during ice storage, in the oxygen radical absorbance capacity (ORAC) assay, in a Cu induced low density lipoprotein (LDL) assay and in a human monocyte model. The herring PJs were also exposed to simulated in vitro gastrointestinal (GI) digestion to evaluate possible changes in the ORAC and LDL oxidation assay responses.During optimization of the washed cod mince model, it was found that the starting cod mince should not contain > 20 mg alpha-tocopherol/kg and that cold setting (i.e pre-gelation) as well as too low moisture ( PJ > HMW-PJ > LMW-PJ. These results indicate a major contribution of the PJ protein fraction to peroxyl radical scavenging. All the PJs except the LMW-PJ also extended the Cu induced LDL oxidation lag phase and decreased the rate of LDL oxidation. Herring PJs also showed a capacity to prevent phorbol myristate acetate (PMA) induced reactive oxygen species (ROS) formation in a human monocyte model. The results here ranked the PJs as PJ > HMW-PJ >LMW-PJ. In vitro GI digestion of herring PJs for 165 min, increased the ORAC values of the protein containing PJs up to approx 12.5 fold and extended the LDL oxidation lag phase approx 1.3 fold. Along with this there was a significant increase in formation of peptides that were
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| 4. |
- Sannaveerappa, Thippeswamy, 1976, et al.
(författare)
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Antioxidative Properties of Press Juice From Herring (Clupea harengus) Against Hemoglobin (Hb) Mediated Oxidation of Washed Cod Mince
- 2007
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Ingår i: Journal of Agricultural and Food Chemistry. ; 55:23, s. 9581-9591
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Tidskriftsartikel (refereegranskat)abstract
- The antioxidative effect of herring (Clupea harengus) light muscle press juice (PJ) against hemoglobin-(Hb-) mediated oxidation of washed cod mince during ice storage was tested. The PJ was fractionatedinto low-molecular-weight (LMM; 1, >3.5, and > 50kDa) fractions; it was preheated (10 min, 100 °C) and tested with or without removing heat coagulatedproteins. Its antioxidative effect was compared with that given by endogenous levels of two tentativeantioxidant candidates: ascorbic acid and uric acid. Oxidation was followed by determining rancidodor, peroxide value, and redness. Whole herring PJ and the LMW-PJ fraction significantly (p
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| 5. |
- Sannaveerappa, Thippeswamy, 1976, et al.
(författare)
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Changes in the Antioxidative Property of Herring (Clupea harengus) Press Juice during a Simulated Gastrointestinal Digestion
- 2007
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Ingår i: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 55:26, s. 10977-85
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Tidskriftsartikel (refereegranskat)abstract
- The aqueous fraction (press juice, PJ) from herring muscle was recently shown to inhibit hemoglobin-mediated oxidation of washed fish mince lipids during ice storage. As a first step to evaluate potential in vivo antioxidative effects from herring PJ, the aim of-this study was to investigate whether herring PJ retains its antioxidative capacity during a simulated gastrointestinal (GI) digestion. Press juice from whole muscle (WMPJ) and light muscle (LMPJ) was mixed with pepsin solution followed by stepwise pH adjustments and additions of pancreatin and bile solutions. Digestive enzymes were removed from samples by ultrafiltration (10 kDa). Before, during, and after digestion, samples were analyzed for their peptide content and for antioxidative properties with the oxygen radical absorbance capacity (ORAC) and the low-density lipoprotein (LDL) oxidation assays. From 0 to 165 min of digestion, the content of
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| 6. |
- Sannaveerappa, Thippeswamy, 1976, et al.
(författare)
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Evaluation of Occasional Nonresponse of a Washed Cod Mince Model to Hemoglobin (Hb)-Mediated Oxidation
- 2007
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Ingår i: Journal of Agricultural and Food Chemistry. ; 55:11, s. 4429-4435
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Tidskriftsartikel (refereegranskat)abstract
- An emerging model to test antioxidants for application in seafoods is washed cod mince fortified withhemoglobin (Hb) as a catalyst. This system has been used to test the antioxidative activity of certainmuscle extracts and some pure compounds such as BHA, BHT, TBHQ, and propyl gallate during icestorage. However, the washed cod mince model has occasionally been resistant to Hb-mediatedoxidation. This has been in cases when the moisture of the model has been minimized by washesat the protein isoelectric point (pH 5.5) to allow for large additions of potentially antioxidative solutions.In this paper, noncontrollable and controllable factors for this intriguing occasional oxidation resistancewere studied. Compositional analyses (lipid content, alpha-tocopherol, and lipid hydroperoxides) andstructural analysis of a “normal” oxidizing model and a stable model were done to identify anydifferences among them. Some controllable factors related to the model preparation that were studiedincluded different washing pH values (5.5-6.6), Hb concentrations (7.2 and 13.5 íM), final modelmoisture contents (75, 81, and 90%), and light exposure during ice storage (0 h, 3-4 h, or 24 h oflight/day). Results revealed a 2-fold higher alpha-tocopherol content in the stable model than in theoxidizing model. Electron microscopy images showed a more and less disrupted myofibrillar structurein the stable and the oxidizing cod model, respectively. This indicated that “cold setting” (i.e., pregelation)of the stable model may have occurred and prevented Hb from diffusing freely in the model.Controllable factors that reduced lipid oxidation in the models were less Hb and lower moisture.
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| 7. |
- Sannaveerappa, Thippeswamy, 1976, et al.
(författare)
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Factors affecting the binding of trout HbI and HbIV to washed cod mince model system and their influence on lipid oxidation
- 2014
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Ingår i: Food Chemistry. - : Elsevier BV. - 0308-8146 .- 1873-7072. ; 143, s. 392-397
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Tidskriftsartikel (refereegranskat)abstract
- Electrostatic interactions between haemoglobin (Hb) and muscle components of fish may be an initial step of Hb-mediated lipid oxidation. This mechanism was investigated by examining the interaction of anionic HbIV and cationic Hbl with insoluble components of washed cod mince under different pH and salt conditions. Lipid oxidation was monitored in parallel using the thiobarbituric acid reactive substances (TBARS) test. Higher binding of Hbl to washed cod mince occurred compared to HbIV, yet HbIV better promoted lipid oxidation. An increase in pH from 5.7 to 6.3 and further to 7.0 lowered both Hb-binding and TBARS development. Addition of NaCl decreased Hb-binding but still did not influence Hb-mediated lipid oxidation. Thus, Hb binding had no consistent effect on lipid oxidation of washed cod mince. Rapid haemin release from the anionic Hb appeared to be a primary facilitator of lipid oxidation, overshadowing the greater binding ability of the cationic Hb. (C) 2013 Elsevier Ltd. All rights reserved.
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