In total, 30 postmenopausal women (

In total, 30 postmenopausal women (mean age = 50.31 ± 4.23 years) participated in this study. All women were at least 2 years naturally menopausal. All participants were normotensive, normocholesterolemic, nondiabetic, nonsmokers and receiving no medication (including vitamin supplements). All of them denied having hot flashes for at least a year. All participants gave informed consent in accordance with the requirement of the Medical Research Ethics Committee of the University of Suez Canal, Egypt.

Garlic soft gels were purchased from Puritan’s Pride, Inc, Oakdale, NY, USA. Each of the soft gel contained A. sativum (from 500:1 extract) equivalent to 1000 mg of fresh garlic bulb. Mature NS seeds were supplied by the Medicinal and Aromatic Research Department, Horticulture Research Station, Agriculture Research Center, Alexandria, Egypt. Nigella seeds were grounded to powder using an electric grinder (model MX-915 C; National, Japan) for 2 min and placed in a glass container prior to use.

The subjects consumed garlic at a dose of two garlic soft gels per day (equivalent to 2000 mg of fresh garlic bulb)47 and crude black seed grounded to powder in a dose of 3 g/day for a period of 8 weeks.48

Before and after this period, fasting blood samples were obtained, and oxidant malondialdehyde (MDA) was measured in the plasma fraction, based on the reaction with thiobarbituric acid to yield a colored product. The optical density of the reaction product was measured at 532 nm using 1,1,3,3-tetramethoxypropane as a standard.49 Antioxidant (superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)) activities were studied in erythrocyte hemolysate as indices of oxidant balance. Erythrocytes were washed with isotonic solution of sodium chloride and centrifuged at 3000 r/min for 10 min where erythrocyte pellets were separated and resuspended in cold distilled water to obtain the erythrocyte lysate.50,51 The resulting erythrocyte lysate was used for measurement of SOD and determination of GSH-Px.52

The GSH-Px activity was given as IU/mL and SOD activity as U/mL. One unit of SOD activity was defined as the amount of protein causing 50% inhibition of the nitroblue tetrazolium salt reduction rate. The MDA concentration was determined by using thiobarbituric acid reaction. MDA, an end product of fatty acid peroxidation, reacts with thiobarbituric acid to form a colored complex that has maximum absorbance at 532 nm.

Statistical analysis was performed using GraphPad Prism version 0.5. Paired t-test was used. Data were given as mean ± standard deviation (SD) with 0.05 as point of minimal statistical significance.