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The aim of this study was to evaluate the effects of enzymatic hydrolysis of camel whole casein on their antioxidant and angiotensin-converting enzyme (ACE)-inhibitory properties. Whole camel casein was hydrolyzed by proteinase K (PK), and the hydrolysates were fractionized by ultrafiltration membranes into three fractions. Semi-preparative reversed-phase high-performance liquid chromatography (RP-HPLC) was used to differentiate the mixture of peptides in the 3 kDa permeate fractions. A fraction (F4) with potentials of ACE-inhibitory activity (IC50 = 73 μg.mL −1 ) and radical scavenging activity (IC50 = 6.8 μg.mL −1 ) was selected for further purification and fractionation. The fraction F4C obtained from a second step purification of F4 showed strong ACE-inhibitory activity (IC 50 = 36 μg.mL −1 ) as well as radical scavenging activity (IC 50 = 3.3 μg.mL −1 ). The results of this study suggest that whole camel casein can be considered as a promising source for the production of peptides with potential of ACE-inhibitory and antioxidant activities.

Background:The importance of viral protein-2 (VP2) of canine parvovirus (CPV) in binding to human cancer cells, production of veterinary vaccines and diagnostic kits has motivated several researches on producing this protein. Objectives: Our purpose was to construct recombinant bacmid shuttle vectors expressing VP2 of CPV using Bac-to-Bac baculoviral expression system. Materials and Methods: Mini-Tn7 transposones engineered in pFastBac1 donor vectors were used to construct expression cassettes of GFP and CPV-VP2. The plasmids were transferred into E. coli DH 10 Bac competent cells. Site-specifi c transposition of the genes into bacmid was accomplished using helper plasmid. Occurrence of Transposition was confi rmed via PCR using specifi c primers and PUC/M 13 universal primers. The recombinant bacmid DNAs were transfected into Sf9 cells using cationic lipids to generate new recombinant baculoviruses expressing GFP and CPV-VP2. GFP and VP2 expressions were evaluated by fl uorescence microscopy and western analysis, respectively. Results: Cloning, subcloning and recombination processes of both GFP and VP2 were accomplished and verifi ed. Accuracy of transfection process was confi rmed by GFP fl uorescence microscopy.VP2 expression was verifi ed by SDS-PAGE and western analysis. Conclusions: Two Bac-to-Bac expression systems were designed to produce recombinant VP2 and GFP in insect cells.

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Transfusional iron overload is a major cause of morbidity and mortality in thalassemia, sickle-cell disease and other chronic anemias. To overcome these problems, orally bio available iron chelators, deferiprone and deferasirox, were used for the treatment of patients suffering from thalassemia. The interactions between deferiprone and deferasirox with the carrier protein, beta-thalassemia hemoglobin (Hb), were investigated using fluorescence, circular dichroism (CD) and UV-visible measurements at physiological condition. Strong fluorescence quenching on interactions of the above drugs with beta-thalassemia Hb were observed. Fluorescence quenching data of thalassemia Hb in the presence of deferasirox have shown greater affinity of binding. The number of binding sites to Hb for deferasirox was found to be more relative to those of the deferiprone. The effects of these drugs on the oxygen affinity of the thalassemia Hb were studied by spectroscopic methods using sodium dithionite. Results indicated that deferiprone reduces oxygen affinity (increases oxygen releasing ability) of Hb, while in the presence of deferasirox, oxygen affinity of Hb has significantly increased by dose-dependent manner. As such, deferasirox exhibited opposite effect relative to deferiprone on the function of thalassemia Hb. In clinical dose of deferiprone, CD results showed that, the alpha-helical content of thalassemia Hb significantly increased. By use of the clinical dose of deferasirox, however, a decrease in alpha-helical content of protein was observed, which resulted in decreasing stability of thalassemia Hb. Our study showed that reduction in stability of thalassemia Hb in the presence of deferasirox induced higher conformational changes in protein.