Análise comparativa de protocolos para extração de DNA genômico em Prosopis juliflora (Sw.) DC

Abstract

The objective of the present research was to compare the efficiency among seven protocols adapted for the extraction of genomic DNA from the species Prosopis juliflora (Sw.) DC. The protocols used were based on their buffers: SDS 10%, CTAB 5%, Sorbitol, CTAB 3% and Sorbitol, SDS 0.7% and NaCl, CTAB 2%, CTAB 2% and NaCl 1.4M. In all tests, the use of β-mercaptoethanol, liquid nitrogen, proteinase K and RNAses was eliminated. The samples consisted of leaf primordia in each specimen in triplicate. The quantity and quality of the extracted DNA were evaluated by electrophoresis in 1% agarose gel and by reading the absorbances in a spectrophotometer. For amplification reactions, the ISSR primer was used. Among the tested extraction buffers, SDS 10%, CTAB 5% and CTAB 3%, and Sorbitol were the most efficient for P. juliflora. Of these three protocols, CTAB 3% and Sorbitol showed a better level of purity despite the lower amount of DNA (123 ng/µL) compared to 10% SDS and 5% CTAB buffers (312 and 321 ng/µL, respectively, and high content of contaminants). We conclude that it is possible to use extraction protocols without additives that are harmful to human health and at a lower cost in the extraction process.