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The aim of this study was to investigate the effect(s) of a mixture ofNigella sativaseeds (N. sativa; black cumin or fennel) and honey on (i) the modulation of cardiovascular disease (CVD) risks among hypercholesterolemic and healthy subjects; and (ii) to assess the lipid-soluble antioxidants capacity of samples using the photochemiluminescence (PCL) method. Sixty-five subjects, aged twenty-five to fifty-eight, were enrolledand assigned to three groups. Two groups of healthy andhypercholesterolemic subjects were supplemented with N. sativa seeds and honey at 50 mg/kg (body weight) daily for three months. The third group served as control (healthy subjects without supplementation). Fasting blood samples were taken at baseline and again after three months of supplementation to measure (i) total cholesterol (TC), (ii) triglycerides (TG), (iii) low density lipoprotein-cholesterol (LDL-c), (iv) high density lipoprotein-cholesterol (HDL-c), (v) blood glucose, and (vi) hemoglobin concentrations. The findings were significant (p  0.05),indicatingthat N. sativa seeds mixed with honey had hypolipidemic, antiobesity and hypotensive effects.Results showed significant reductions in TG (20.1%), TC:HDL-c (12.3%),accompanied by increased HDL-c (15.0%) among healthy subjects.Supplementation also significantly decreased TC (6.2%), TG (13.3%), TC:HDL-c (19.5%),with increased HDL-c (8.4%) in the hypercholesterolemic group. Furthermore, there were significant reductions in body weight, body mass index and body fat by 2.3%, 2.2%, 4.5%, and by 1.8%, 1.9%, 4.5% in healthy and hypercholesterolemic subjects, respectively. Blood pressureslowering werealso observed in hypercholesterolemic subjects with significant reductions in systolic blood pressure (3.9%) and diastolic blood pressure (5.5%). There were no significant effectsfromsupplementation on blood glucose or hemoglobin concentrations. It is postulated that the positive effects observed may be due to antioxidant activity. The combination of of N. sativa seeds with honey showed higher synergistic effectswhen compared withsupplementation ofN. sativa seeds or honey on their own. Overall, these findings suggest that a mixture of N. sativa seeds with honey hasbeneficial effects in loweringthe citedrisk indicators for cardiovascular disease as a natural source of antioxidant activity; thus aidingthe maintainence of health bylowering CVD risk factors.

This research was undertaken to investigate the effect of Roselle (Hibiscus sabdariffa. L) extract on the physical properties and stability of extra virgin olive oil emulsions. Four different emulsions were prepared with methanolic Roselle extract (0.01 and 0.02%) and 0.02% BHT (commercial antioxidant) as well as without the extract/ antioxidant (control). The physical properties were studied in terms of pH, droplet size distribution, microstructure, viscosity and stability towards phase separation and lipid oxidation (under accelerated oxidation at 60°C for 10 days). The emulsions with Roselle extract was found to exhibit lower polydispersity and more uniform droplet size as compared to control and BHT emulsions. The highest viscosity was observed for the emulsion with 0.02%. The BHT emulsion was the most unstable towards phase separation after 15 days of storage at 5°C. A protective effect of Roselle extract against lipid oxidation in the emulsions was clearly observed at 0, 2, 8 and 10 days of accelerated storage (at 60°C) with considerably low total oxidation values (5.4 to 13). All emulsions showed insignificant deterioration with peroxide value < 20 meq/kg after oxidation period. This study provided important preliminary data on possibility of applying Roselle extract (which is known to content a significant amount of bioactive compounds) in producing functional food emulsions with acceptable properties and stability. Keywords: antioxidants, emulsion, roselle extract, stability, properties