acid-phosphatase and 1-1-diphenyl-2-picrylhydrazyl

Topics: Acid Phosphatase; Animals; Binding Sites; Biphenyl Compounds; Catalysis; Cattle; Copper; Electron Spin Resonance Spectroscopy; Kinetics; Osteoporosis; Oxidation-Reduction; Peroxidases; Picrates; Protective Agents; Reactive Oxygen Species; Serum Albumin, Bovine; Spectrometry, Fluorescence; Superoxide Dismutase; Thermodynamics; Time Factors

Lipofuscin-like pigments (LFLP) are considered a hallmark of aging. The intracellular LFLP formation rate is negatively correlated with the life expectancy of cell. In food quality, increase of LFLP not only affects the appearance but also causes loss of nutritional value.. The accumulation of LFLP increased during storage of all walnuts. LFLP fluorescent intensities of walnuts with 4%, 6%, 12% and 16% moisture at the end of storage were 8.1, 4.8, 4.3 and 2.8 times those at the beginning, respectively. The LFLP accumulation of walnuts with high moisture was found to be negatively correlated with soluble sugars and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical quenching rate, but positively correlated with the content of hydroxymethylfuraldehyde (HMF). While the LFLP accumulation of walnuts with low moisture had a strong positive correlation with anisidine value, it exhibited high negative correlations with acid phosphatase activity, DPPH(•) quenching rate and tocopherol content.. In walnuts with low initial moisture, lipoxidation products increased markedly during storage and these products might provide the source for LFLP accumulation. On the other hand, in walnuts with high initial moisture, reducing sugars derived from the hydrolysis of soluble sugars might play an important role in initiating the Maillard-like reaction, leading to LFLP accumulation.

Topics: Acid Phosphatase; Biphenyl Compounds; Carbohydrate Metabolism; Diet; Food Storage; Glycosylation; Humans; Juglans; Lipid Peroxidation; Lipofuscin; Maillard Reaction; Nutritive Value; Nuts; Picrates; Tocopherols; Water