Potato Skin: A Potential Bio stimulating agent for used Motor Oil Bio degraders

The potential of potato skin (PS) to enhance bioremediation of soil polluted with used motor oil was investigated gravimetrically for a period of 42 days. Polluted soil was amended with 5%, 10% and 15% (w/w) of PS. Loss of total petroleum hydrocarbon (TPH), microbial growth and germination indices were all investigated throughout the study period. At the end of 42 days, there was significant oil loss of 73.85% in the amended soil. Hydrocarbon-utilizing bacterial (HUB) counts were significantly higher(P≤0.05) in the amended option ranging from 6.7 x 106 to 22.3 x 106CFU/g. The HUB isolated from the oil-contaminated soil were identified tentatively as belonging to the genera: Bacillus, Arthrobacter, Rhodococcus, Corynebacterium, Pseudomonas, Staphylococcus and Acinetobacter. Similarly, fungal counts ranged from 4.8 x 105 to 59.0 x 105 CFU/g. Aerobic fungi isolated were identified tentatively as Aspergillus niger, Aspergillus sp., Pennicillum sp., Phialophora sp., Cladosporium sp. and Verticillum sp. Germination index of 69.46% was recorded in the amended option. Oil loss and microbial growth were significantly higher (P≤ 0.05) in the amended option than the control option. Potato skin, therefore can offer a good alternative in bioremediation of soil polluted with used motor oil.