Effect of Some Ecological Factors on Thegrowth of Aspergillus niger and Cladosporium sphaerospermum

Indoor airborne fungi have been implicated in human health problems, damage to building materials, books, clothes and stored foods, which effected by different ecological factors. Aspergillus niger and Cladosporium sphaerospermum are the most dominant indoor airborne fungi were obtained from our previous study. The effect of normal indoor conditions (Temperature and Relative Humidity) on their growth was studied. Including their nutrients growth requirements. The PDA medium was the appropriate growth medium for Cl. sphaerospermum, with a significant difference at (p<0.05); where as GYA medium was the appropriate growth medium for A. niger, with no significant difference. The temperatures 25 and 30°C favored colony diameter growth for Cl. sphaerospermum and A. niger, respectively with a significant difference at (p<0.05). The growth of Cl. sphaerospermum increased to reach its maximum at 100% RH. Whereas, A. niger prefers to grow at lower RH comparing to Cl. sphaerospermum to reach its maximum at 75% RH with a significant difference at (p<0.05). Controlling the normal indoor conditions can play a significant role in reducing the growth of indoor airborne fungi. Cl. sphaerospermum can be used as indicator fungi for the high humidity level in residences. The result has proved that keeping the humidity low enough can prevent fungi growth.