Журнал микробиологии и патологии

Modified Methods for Quick and Safe Extraction of DNA from Common Microbiological Samples

Abstract

O.O. Ajayi1,2*, A. Adekanmbi1, O. E. Fagade1, M. Dianda2

Isolating and purifying DNA are very important steps in DNA molecular techniques used in microbiological studies for the identification of genotypes, traits associated with genes of interest, and genetic diversity. Plant and soil materials are among the most difficult for high quality DNA extractions. While carrying out DNA extraction for over 2000 different sample types using 2 different kits (ZYMO Bacterial/Fungal extraction kit, ZYMO Soil extraction kit, ZYMO Plant extraction kit and E.Z.N.A. soil DNA Kit) and crude extraction CTAB method, several modifications were made to ensure extraction of good quality DNA. These modifications in the methods were documented; re used severally to confirm their accuracy and was done without the use of liquid Nitrogen. The extracted DNA obtained from CTAB extraction were extremely high and was diluted for use in PCR using a ratio 1:10 of DNA to water while those obtained from the kit were used directly (but in small quantities ~0.5 μL) or diluted in a ratio 50:50. The mean DNA yields obtained for CTAB extraction were between 500-4000 mg/μl while that obtained for the kits were between 70-400 mg/μl. The 260/280 nm absorbance ratio had a high level of purity between 1.8-2.0. These modified methods can be used for day to day extraction processes in the laboratory.