Antiradical capacity

ACW—Integral Antiradical Capacity of Water-Soluble Compounds... 

During determination of the integral antiradical capacity of blood plasma (ACW) by the PCL method, the above-mentioned substances, among others, will be detected primarily. 

Figure 9 Antiradical capacity in the lipid phase of blood plasma (ACL) determined with the PCL method versus vitamin E (VE) as a sum of a- and y-tocopherols determined with HPLC. (From Ref. 28.)...

Modified procedure (ACP kit) Total plasma protein is isolated from low-molecular-weight plasma antioxidants in a single-step liquid gel chromatography procedure and its antiradical capacity ACP is measured in the ACW assay. 

The antiradical capacity of proteins is thought to be an important component of the total antioxidant capacity of blood plasma. Analysis of the ACW of blood plasma showed, that under normal conditions, its main components are the UA and ASC. The rest of the total antiradical capacity (ACR), which can be... 

Investigations of the effects of UV- and hypochlorite-induced oxidative modification of 20 amino acids and human serum albumin (HSA) on their antiradical properties showed unexpected results [36], Seven amino acids (cystine, histidine, methionine, phenylalanine, serine, tryptophan, and tyrosine) and HSA developed ACW following oxidation (see examples in Fig. 14). The fresh (produced in 1998) HSA from Serva had no antiradical capacity, but it acquired this quality during irradiation. The out-of-date HSA sample (Dessau, GDR, 1987, expiration date 7/1/1992) showed a remarkable ACW even in an unirradiated state. 

Figure 15 Antiradical capacity of histidine (2 mmol/L) undergoing chemical (NaOCI) and physical (UV, 254 nm) oxidation in equivalent concentrations of ascorbic acid used as calibrator. For UV dose 1 = 60 s, dose 2 = 120 s. For NaOCI after 45 min of incubation with 16 (dose 1) or 32 (dose 2) mg/L NaOCI.

G Lewin, G Kuhn, U Deuse, M Buhring, B Ramsauer, I Popov. Paradox of the antiradical capacity of blood plasma proteins. In SFRR Europe Summer Meeting, July 2-5, 1999, Dresden, Germany. Book of Abstracts, p 029. 

In both CL systems the key measured parameter for determining of the total water-soluble blood serum component AOA (ACW - integral antiradical capacity of water soluble compounds ) is the latent period. It decides as time from the oxidation initiation moment to a point of intersection on an axis of time of the tangent attached to CL-curve in the point corresponding to a maximum of its first derivative dl/dt (Figure 18.7). Calibration of devices was carried out on ascorbic acid, and the total AOA of water-soluble components (ACW) was expressed in the equivalent ascorbic acid content in one liter of blood serum (pmol/L). The measurement error of this parameter for the first device made no more than 20%, for the second didn t exceed 5%. 

FIGURE 18.4 Correlation of ACW measurement results for donors and recipients (ACW - integral antiradical capacity of water soluble compounds ) for model with hemoglobin (ACW, pmol/L (Hb)) and with ABAP (ACW, pmol/L (ABAP)) r-correlate coefficient. 

Measurement results of the antiradical capacity of blood serum and its some individual components for recipients with liver disease... 

Genovese, M. and Lannes, S. 2009. Comparison of total phenolic content and antiradical capacity... 

Shpigun, L. K., Ya. V. Shushenachev, and P. M. Kamilova. 2008. Automatic methods for testing antiradical capacity of biocompounds. In Chemistry The Global Science. 2nd EuChem Chemistry Congress. Torino, Italy. 

Some other features are used to measure antioxidant power, for example, an antiradical capacity (ECso value), which represents the amount of AOX required to reduce the initial concentration (absorbance) of the radical by 50% [6]. This value can be determined graphically by plotting the absorbance against the AOX concentration or calculated by using the corresponding linear regression equation. 

Derivatives of chlorophyll a were found to be more effective radical quenchers than those of chlorophyll b. Furthermore, metal-lree derivatives such as chlorins, pheophytins, and pyropheopytins exhibited significantly lower antiradical capacity than metaUo-derivatives such as Mg-chlorophylls, Zn-pheophytins, Zn-pyropheo-phytins, Cu-pheophytin a, and Cu-chlorophyllins. It seems that dietary chlorophyll derivatives prevalent in both fresh and processed foods and dietary supplements have antioxidant and antimutagenic activities [60]. 

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