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On this thread I'll cite some abstracts about the antioxidant capacities of various substances. Notice that in some of hte experiments, refined olive oil or lard are used, because they are biochemically unstable.
Food Chem Toxicol. 1996 May;34(5):449-56.
Extracts of herbs and spices are increasingly of interest in the food industry because they retard oxidative degradation of lipids. There is also increasing interest in the antiviral activity of plant products. A liquid, deodorized rosemary extract and an oily extract of a mixture of Provençal herbs were tested for antioxidant and antiviral action in vitro. The rosemary extract (Herbor 025) and the extract of Provençal herbs (Spice Cocktail) inhibited peroxidation of phospholipid liposomes with 50% inhibition concentration values of 0.0009% (v/v) and 0.0035% (v/v), respectively. Herbor 025 and the spice cocktail (at 0.2%, v/v) reacted with trichloromethylperoxyl radical with calculated rates of 2.7 x 10(4) s-1 and 1.5 x 10(3) s-1, respectively. The main active components in the herbal preparations, carnosol and carnosic acid, at 0.05% (v/v) react with rate constants of (1-3) x 10(6) M-1 sec-1 and 2.7 x 10(7) M-1 sec-1, respectively. Both extracts show good antioxidant activity in the Rancimat test, especially in lard. Herbor 025 and the spice cocktail inhibited human immunodeficiency virus (HIV) infection at very low concentrations which were also cytotoxic. However, purified carnosol exhibited definite anti-HIV activity at a concentration (8 microM) which was not cytotoxic. Both preparations promoted some DNA damage in the copper-phenanthroline and the bleomycin-iron systems. The two herbal preparations possess antioxidant properties that may make them useful in the food matrix.
J Food Prot. 2001 Sep;64(9):1412-9.
In this study, the antioxidant properties of Mediterranean food spices (annatto, cumin, oregano, sweet and hot paprika, rosemary, and saffron) at 5% concentration and of common food additives (butylated hydroxyanisole [BHA], butylated hydroxytoluene [BHT], and propyl gallate) at 100 microg/g are compared. The ability of these compounds to inhibit lipid peroxidation was, in decreasing order, rosemary > oregano > propyl gallate > annatto > BHA > sweet paprika > cumin > hot paprika > saffron > BHT. Deoxyribose damage is partially inhibited in the presence of cumin extract that exhibits the strongest protective action. The rest of the spices also protect deoxyribose better than the BHA and BHT used in the assay. Finally, the results obtained in the assay point to the prooxidant effect of propyl gallate. Hydrogen peroxide scavenging activity is measured by using peroxidase-based assay systems. In aqueous medium, the spice extracts show lower antioxidant activity than propyl gallate, the decreasing order being cumin > oregano > annatto > rosemary > hot paprika > sweet paprika. BHA and BHT did not scavenge H2O2 Spices are able to scavenge HOCl and protect alpha1-antiproteinase. The results indicate that rosemary and oregano are more effective HOCl scavengers than the other substances analyzed, which, in decreasing order, were propyl gallate, annatto, sweet and hot paprika, saffron, and cumin. The effect of Mediterranean food spices on the oxidative stability of refined olive oil tested by the Rancimat method was compared with common food additives during storage (72 h, 2, 4, and 6 months) at room temperature. The results showed that the spice extracts analyzed have significant stabilizing effects (P < 0.05).
J Food Prot. 2001 Dec;64(12):2037-46.
Several Mediterranean and tropical fruits have been analyzed in order to assess their antioxidant activity compared with that of common food additives (butylated hydroxyanisole [BHA], butylated hydroxytoluene [BHT] and propyl gallate). Among Mediterranean fruits, red grape and plum were more effective (P < 0.05) scavengers of peroxyl radicals than BHA, BHT, and propyl gallate. Of the tropical fruits, banana was the most effective scavenger of peroxyl radicals. Mediterranean and tropical fruits showed very good scavenger activity against hydroxy radicals (OH*), protecting deoxyribose better than BHA and BHT. The HOCI scavenging ability of Mediterranean fruits tested was, in decreasing order, lemon > plum > apricot > white grape > melon > red grape > mandarin > watermelon > peach > medlar > apple > orange > cherry > strawberry. However, the four varieties of pear were poor scavengers (P < 0.05). Among tropical fruits, the order of efficiency as HOCI scavengers was passion fruit > lime > passiflora > kumquat > avocado > pineapple > physalis > papaya fruit > carambola > mango > banana. All Mediterranean fruits showed an effect on hydrogen peroxide except peach. Tropical fruits also had a strong effect on hydrogen peroxide except avocado, which had no effect. The effect of Mediterranean and tropical fruits on the protection factor of refined olive oil, analyzed by the Rancimat method and compared with common food additives, was clear. Watermelon conferred a significantly (P < 0.05) greater protection than the other Mediterranean fruits. Among tropical fruits, physalis had the most stabilizing effect.
J Agric Food Chem. 2002 Sep 25;50(20):5566-70.
Changes in the concentration of tocopherol, monophenols, o-diphenols, squalene, and polyunsaturated fatty acids in olive oil were evaluated during 1 year at various storage conditions. Samples of two different extra virgin olive oil (EOO), produced in Calabria (Italy), were stored in dark and in colorless bottles, filled up completely or to half, in order to simulate the domestic storage conditions. The extent of oxidation or photooxidation was monitored by periodic measurements of peroxide values and the rate of degradation of alpha-tocopherol, o-diphenols, squalene, and polyunsaturated fatty acids. The quantitative analysis of the constituents has been performed by HPLC-DAD, HPLC-MS, and GC-MS. The main changes in the concentrations of the analyzed compounds were associated with the major oxygen level in the half-empty glass bottles. alpha-Tocopherol was the first molecule to be oxidized (-20% after 2 months, -92% after 12 months). Squalene and o-diphenols were protected in the first months by the presence of alpha-tocopherol, and their content decreased significantly only after 6 and 8 months, respectively, in the half-empty bottles. The concentration of polyunsaturated fatty acids remained almost constant during 8 months for all four different storage conditions; their oxidation started when the level of the antioxidants decreased.
J Agric Food Chem. 1999 Oct;47(10):4025-32.
The role of squalene in olive oil stability was studied for various concentrations and experimental conditions. No effect was found in induction periods of olive oil at elevated temperatures using the Rancimat apparatus. Samples were then stored at 40 and 62 degrees C in the dark, and the extent of oxidation was followed by periodic measurements of peroxide value and conjugated dienes. A concentration dependent moderate antioxidant activity was evidenced which was stronger in the case of olive oil compared to that found for sunflower oil and lard. In the presence of alpha-tocopherol (100 mg/kg) and caffeic acid (10 mg/kg) the contribution of squalene (7000 mg/kg) was not significant. No radical scavenging activity was observed using DPPH(*) in 2-propanol. The weak antioxidant activity of squalene in olive oil may be explained by competitive oxidation of the different lipids present which leads to a reduction of the oxidation rate. Squalene plays a rather confined role in olive oil stability even at low temperatures.
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| I have been always "scared" of the high glycemic index when eating banana but it seems to be a good scavenger of peroxyl radicals! Good news indeed. Hans, do you know anything about the antioxidant capacity of soy sauce? It's used here during meat cooking so I hope it might offset some of the bad effects of oxidized cholesterol and oleic acid. |
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My diet is very rich in "simple carbs," including sugar-rich cookies. The "trick" is to eat such items with protein-rich foods (I use ricotta and "regular" cheese) along with some fat that is SFA-rich but UFA-poor). If you do that, you won't have weight or health issues (unless you eat way too much calories). I am 5'9" tall, early 40s, and weigh about 140. Needless to say, I am thin. The rest of my "blood relatives" are all overweight. The big difference is that they eat cooked meat and have a UFA-rich diet. None smoke or drink, and all get plenty of sleep.
As to soy sauce, take a look at:
http://www.foodproductdesign.com/hotnews/66h98633.html |
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