Ulfat M. Omar

Antiproliferative Activity of Egg Yolk Peptides in Human Colon Cancer Cells

ABSTRACT Egg yolk peptides were successfully prepared from egg yolk protein by-products after lecithin extraction. Defatted egg yolk protein was hydrolyzed with pepsin and pancreatin and purified by gel filtration to produce egg yolk gel filtration fraction (EYGF-33) with antiproliferative activity. The highlight of this study was that the peptide EYGF-33 (1.0 mg/ml) significantly inhibits cell viability of colon cancer cells (Caco-2) with no inhibitory effects on the viability of human colon epithelial normal cells (HCEC) after 48 h. Reduced cell viability can be explained by cell cycle arrest in the S-phase in which DNA replication normally takes place. EYGF-33 significantly enhanced the production of superoxide anions in the mitochondria of Caco-2 cells; this could activate a mitochondrial apoptotic pathway leading to typical Poly Adenosine diphosphate-ribose polymerase (PARP) cleavage as observed in the Western blot result. The induction of apoptotic cell death by EYGF-33 was supported by the externalization of phosphatidylserine (PS). However, further elucidation of the mechanism of EYGF-33-mediated apoptosis would provide further support for its use as a potential therapeutic and chemopreventive agent.

In Vitro Cytotoxic and Anticancer Effects of Zamzam Water in Human Lung Cancer (A594) Cell Line

BACKGROUND Zamzam water is naturally alkaline and rich in a variety of minerals which may represent a powerful tool for cancer therapy. In this research, the cytotoxic effects of Zamzam water were investigated in human lung cancer (A549) cell line and compared with human skin fibroblasts (HSF). METHODS Two different preparations of Zamzam water were used: Z1, with pH adjusted to 7.2 and Z2, with no pH adjustment. The effects of both treatments on the morphology of the A549 and HSF cell lines were investigated. The cell viability of HSF and A549 cells was identified by the MTT assay and trypan blue exclusion. Detection of apoptotic cells and cell cycle analyses were determined using flow cytometry. Moreover, reactive oxygen species (ROS) were measured for both cell lines. RESULTS Both Zamzam water treatments, Z1 and Z2 showed reductions in the cell viability of A549 cells. Cell death occurred via necrosis among cells treated with Z2. Cell cycle arrest occurred in the G0/G1 phases for cells treated with Z2. Cellular and mitochondrial ROS productions were not affected by either treatment. CONCLUSION Our findings indicate that Zamzam water might have potential therapeutic efficacy for lung cancer.

ASSESSMENT OF THE ANTIOXIDANT PROPERTIES OF THE MOST COMMON COFFEE BREWS AVAILABLE IN THE LOCAL MARKETS OF THE WESTERN REGION OF SAUDI ARABIA

The purpose of the current study is to determine the antioxidant activity of the most commonly used coffee brews in the Western region of Saudi Arabia. Further, total phenolic and flavonoid contents were measured and antioxidants properties including ferric reducing antioxidant power and ferrous ion chelating activity, DPPH radical scavenging activity, and scavenging of hydrogen peroxide assays were also determined. Results of study revealed that phenolic contents were 741, 835 and 578 μg/ml of gallic acid/2 g of coffee, and the total flavonoid contents were 711, 802, and 828 μg/ml of catechin/2 g of coffee for Nescafé red mug, Turkish coffee and Espresso, respectively. The inhibition percentage of hydrogen peroxide showed highly significant reduction (p<0.001) in Turkish coffee compared to Nescafé red mug. Further, DPPH activity also showed highly significant reduction (p<0.01) in Espresso and Turkish coffee compared to Nescafé red mug, whereas, Espresso showed a highly significant increase (p<0.01) in reducing power activity. Regarding the metal chelating activity, Espresso showed a significant decrease (p<0.05) in metal chelation activity as compared to Nescafé red mug. The current study demonstrated that Nescafé red mug, Turkish coffee and Espresso, were the most consumed coffee types in the Western region of Saudi Arabia according to the survey. These three types of coffee showed high phenolic and flavonoid contents as well as a high antioxidant activity. Huda A. Al Doghaither * , Ashjan M. Almowalad, Ayat M. Shorbaji, Ayat B. Al-Ghafari, and Ulfat M. Omar

The Effect of Adding Different Concentrations of Cows’ Milk on the Antioxidant Properties of Coffee

Polyphenols have been widely studied and considered as a health promoting and disease preventive agents in humans. Several studies investigated the antioxidant properties of polyphenols and their abilities to eliminate free radicals. In this study, the antioxidant activity of coffee in the presence of different types of cows’ milk at different concentrations, 10% or 20%, was investigated. Our results showed that milk could either enhance the scavenging of DPPH or decrease the metal chelating and metal reducing activity of polyphenol. However, more investigations are required to evaluate the mechanisms by which fats in milk can alter the antioxidant activity of coffee.