Open Access Original Research Article

Isolation and Identification of Resistant Bacteria from Petroleum Producing Vicinity by Gene Amplification and Sequencing

O. Aleruchi, O. Obire

Biotechnology Journal International, Page 1-8
DOI: 10.9734/bji/2021/v25i330139

This investigation focuses on molecular identification of antibiotic resistant bacteria isolated from petroleum producing vicinity using 16S rRNA sequencing based technique. The bacterial 16s rRNA gene sequences were amplified using polymerase chain reaction, sequenced,  characterized and compared by using primers which has been compared to national center for biotechnology information (NCBI) sequence database. The presence of the plasmid mediated antibiotic resistance determinants CTX-M and QNRB genes in the bacterial isolates were analyzed. A total of four bacterial isolates that were resistant to all the antibiotic agents used were identified molecularly. The BLAST results showed 100 % similarity and phylogenetic study indicated that the genes were evolutionarily related to Morganella morganii, Pseudomonas xiamenensis, Chryseobacterium cucumeris and Staphylococcus sp., respectively. The genes obtained were submitted to the NCBI gene bank and were assigned accession number; MN094330, MN094331, MN094332 and MN094333, respectively. CTX-M and QNRB genes were however absent in the bacterial isolates. The result identified some peculiar abilities of the bacterial isolates to be resistant to antibiotics and suggests a correlation with resistance and hydrocarbon utilizing bacteria. The level of resistance could be as a result of the disinfection process during wastewater treatment procedure or the same adaptive mechanisms possessed by the isolates to control the hydrocarbon concentration in their cell. The study also clearly indicates that these wastewaters, when discharged into the environment directly may pose a risk for the spread of antibiotic resistant bacteria.

Open Access Original Research Article

Effects of Process Parameters on the Activities of Enzymes by Different Species of Aspergillus in Crude Polluted Soil Sites

J. M. Madu, A. I. Ogbonna, C. I. C. Ogbonna

Biotechnology Journal International, Page 9-17
DOI: 10.9734/bji/2021/v25i330140

The effects of temperature, pH and incubation time on amylase, protease and cellulase activity by different species of Aspergillus in crude oil polluted soil sites in Nigeria were studied. Incubation period, Optimal pH values and temperatures for the enzymes produced by the different micro‐organisms were determined. The production of amylase by A. fumigatus and A. niger isolated from crude oil polluted sites showed that both fungi had their peaks on the first day of incubation for amylase, protease and cellulase. A. niger showed higher stability across a range of pH (3-6) and temperature (25-70oC) changes in all the enzyme activities. Further experiments are recommended to purify the secreted enzymes and stability studies will be performed to enhance the application of enzyme to commercial level.