No abstract

Agarose gel electrophoresis is commonly used to separate different species of nucleic acids. We compare four different methods of extraction which are commonly used. These methods include buffer extraction, electroelution, glass bead extraction and extraction of DNA from low-melting agarose. The results show that DNA extracted by these four methods is comparable in their ligability to the PMT 21 vectors and the plasmids with insert can be used for subsequent transfections of competent bacteria. There is a higher yield for buffer extraction and electroelution when compared with glass bead extraction and low melting agarose (p less than 0.05). To conclude, the four commonly used methods for DNA isolation are comparable qualitatively. But the simplest method, namely buffer extraction, has the highest yield.

The objective of this study was to compare the antioxidant activity and cytotoxicity of Durio zibethinus M. (Durian) leaf extract from two extraction methods. Ultrasound-assisted extraction and Accelerated-solvent extraction were used to produce crude extract. The results revealed that UAE achieved 3× higher in total phenolic content in the leaf extract compared to ASE. DPPH radical scavenging activity was 4.6× higher in leaf extract from ASE. No significant differences reported in ferric reducing power, and total flavonoid content of the leaf extract between the two methods. Cytotoxicity via MTT assay demonstrated no significant differences in cell viability upon exposure to the leaf extract from both methods. This suggested that they were appropriate in producing Durio zibethinus M. leaf extract for end use application in food related product. Both ensured similar level of safety in Durio zibethinus M. leaf extract as a new potential ingredient for the food industry.