RESUMO
The amino acid profile and the effects of the seed extracts of Sphenostylis sternocarpa, Monodora myristica and Mucuna sloanei were studied based on their ability to inhibit haemoglobin polymerization and improve the Fe2+/Fe3+ ratio of sickle cell erythrocytes. The samples were fractionated into crude aqueous extract (CAE), fat-soluble (FAS), butanol-soluble (BUS) and water-soluble (WAS) fractions. The CAEs of the samples ranked highest in amino acid content in the range of S. sternocarpa (7.12 ± 0.00 g/100g)>M. myristica (6.00 ± 0.15 g/100g)>M. sloanei (3.56 ± 0.21 g/100g). The amino acids identified in appreciable quantities in the seed samples included Phe, Leu, Val, Ile, His, Arg, Tyr, Met, among others. The extracts inhibited polymerization to varying degrees with CAE of both S. sternocarpa and M. myristica, as well as the WAS of M. myristica eliciting significantly (p<0.05) high percent inhibition of polymerization when compared with Phe standard. The extracts improved the Fe2+/Fe3+ ratio of HbSS blood from 1.36% for CAE of M. sloanei to 85.04% for CAE of S. sternocarpa; and from 11.03% for WAS of S. sternocarpa to 36.08% for WAS of M. sloanei. These legumes could, therefore, have immense nutritional and therapeutic importance in the management of sickle cell disease and other related diseases.
RESUMO
Logistic response of antioxidants to lipid peroxide concentration in carbon tetrachloride toxicity in rabbit liver was evaluated. Carbon tetrachloride (CCl4), ethanol extracts of Chromolaena odorata (ETECO), sylimarin (a known hepatoprotective agent) and water, were used to induce variations in the oxidant/antioxidant balance in the test and control animals. This was used as a model to study the delicate balance between the activities and/or the intracellular concentrations of these antioxidants and lipid peroxide. Concentrations of lipid peroxidation product (malondialdehyde) were estimated to access the degree of oxidation of the polyunsaturated fatty acids in the liver tissue. Glutathione (GSH) concentration was estimated to capture the non-enzymatic antioxidant concentration, while glutathione-s-transferase (GST), superoxide dismutase (SOD), and catalase (CAT) activities were assayed in the liver to assess the enzymatic antioxidant activities. Results obtained from this study showed that the concentrations of lipid peroxidation product (malondialdehyde) varied in a logistic fashion with the nonenzymatic antioxidant (glutathione) and the enzymatic antioxidants (glutathione-stransferase, superoxide dismutase, and catalase). The concentration of the peroxidation product and the concentration/activity of the antioxidants were inversely related, maintaining a highly logistic relationship (R2 = 0.99). The non-enzymatic antioxidant (GSH) concentration and the enzymatic antioxidant (GST, SOD, and CAT) activities were found to be directly related in a sigmoidal manner (R2 = 0.98). These observations indicated that oxidant/antioxidant concentrations and activities in a rabbit liver tissue is tightly related and mathematically associated.
RESUMO
The ethanol extract of the leaf of Chromolaena odorata (Linn) was assessed for freeradical- scavenging and antioxidant potentials. Ability of the extract to scavenge reactive intermediates (superoxide ion O2 ·-, hydrogen peroxide H2O2, nitric oxide NO˙, hydroxyl radical OH˙) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, were used to assess its free radical scavenging potentials. Antioxidant potential was studied by assessing invitro inhibition of lipid peroxidation in both the brain (Neuro-protective potentials) and liver homogenates of Fenton-oxidant stressed rabbits. Inhibition of protein oxidation was assessed in-vitro by loss of protein thiol (P-SH), while assessment of the reducing power of the extract was further used to assess antioxidant capacity. Results obtained showed the ability of the extract to scavenge free radicals and reactive intermediates in a dose-response manner. The plant also had good antioxidant capacity. The secondary plant metabolites found earlier in the extract may explain reasons for the bio-efficacy of the plant. These findings are of great importance in view of the availability of the plant and its observed possible diverse applications in medicine and nutrition.