MATERIALS AND METHODS
The expired human packed blood cells used in this research was obtained
from the Blood Bank of Batangas Regional Hospital. The freshly collected
blood was obtained from one of the members of the research team. Sheep
blood that served as the standard came from Research Institute for Tropical
Medicine in Alabang, Muntinlupa City.
The researchers employed the red cell suspension technique in the
preparation of blood agar having expired human blood as the main component.
Two different microorganisms, namely Staphylococcus aureus ATCC 25923
and Staphylococcus epidermidis ATCC 12228, were inoculated in five different
blood agars. These included sheep blood, unwashed expired human blood,
unwashed fresh human blood, washed expired and fresh human blood. The
morphologies and hemolytic patterns were compared. Each type of blood
was added to Trypticase soy agar (Hi-Media, USA) in the preparation of BAP.
BAP using washed expired human blood without test organisms and sheep
blood with test organisms served as the negative control and positive control,
respectively.
The growth of the microorganisms was evaluated in terms of the cultural
characteristics and hemolytic reaction (Forbes et al., 2007). The washed blood
agar was subjected to different storage duration to determine its stability. To
determine the effect of the duration of storage, a batch of culture media was
stored at a refrigerated temperature. The said culture media were then serially
inoculated with Staphylococcus aureus everyday for seven (7) days.