ISOLATION AND IDENTIFICATION OF BACTERIAL CONTAMINANTS FROM PLANT TISSUE CULTURE LABORATORY IN NIFOR

ABSTRACT

This study was carried out to isolate and identify bacterial contaminants from the air and culture material in a tissue culture laboratory at the Nigerian Institute for Oil Palm Research. Settle plate methods were employed for the isolation of bacteria from the air in the tissue culture section at the Nigerian Institute for Oil Palm Research (NIFOR). Standard conventional bacteriological techniques were also employed for the isolation and enumeration of bacteria from materials used for tissue culture experiments. The isolates were identified using cultural, morphological and biochemical characteristics. The data was analyzed using Microsoft Excel and descriptive statistics was used for interpretation of the data. The results showed that the airborne bacterial counts of selected sections in the tissue culture section in NIFOR range from log10 2.03±0.16 cfu/m3 (laminar flow chamber) to log10 2.60±0.09 cfu/m3 (Washroom 1) in the months of March while a higher bacterial count was observed for the month of May with bacterial counts between log10 1.98±0.15 cfu/m3 (Laminar flow chamber) to log10 3.21±0.04 cfu/m3 (Sterilization room). The airborne bacterial counts of tissue culture and growth rooms in NIFOR ranged from log10 1.98±0.13 cfu/m3 (Growth room 1) to log10 2.06±0.20 cfu/m3 (Growth room 3). The corridors to the tissue culture laboratories were also found to have airborne bacterial counts between log10 1.89±0.16 cfu/m3 (incubation room corridor) to log10 2.16±0.15 cfu/m3 (First curtain corridor). The bacterial counts were found to be higher at the second sampling in the months of May- June compared to March-April 2023. The sanitary standards in (Log10 cfu/cm3) relative to the degree of pollution in the indoor environment of the laboratory and growth rooms revealed that 18.18% of the rooms for tissue culture experiment had high levels of contamination while 72.73% had intermediate levels of contamination with only 9.09% of tissue culture section with low level of contamination. The materials and constituents used for tissue culture were also found to be largely contaminated with bacterial isolates and the bioburden levels ranged from log10 2.74±0.02 cfu/ml (Micro x10) to log10 2.88±0.10 cfu/ml. The bacterial isolates obtained from the air and materials used for tissue culture were identified to be Bacillus species, Pseudomonas aeruginosa, Proteus vulgaris, Escherichia coli, Lysinibacillus forsiformis and Enterobacter.