Nondestructive DNA extraction from specimens and bulk samples preserved in DESS solution for DNA barcoding

DNA barcoding of small organisms often requires significant damage or destroy specimens. To address this, the development of nondestructive DNA extraction methods that maintain specimen morphology is crucial. Here, we present a protocol using the supernatant of DESS preservation solution (20% DMSO, 250 mM EDTA, saturated NaCl), which conserve both the morphological characteristics and DNA of biological samples long-term. This method successfully conducted nondestructive barcoding of nematodes preserved in DESS and stored 10 years at room temperature. The protocol also applies to bulk environmental samples, where sediment and seagrass collected in the field are immediately preserved in DESS. This enables the subsequent isolation and individual nondestructive barcoding of meiofauna and diatoms from the preserved environmental samples in the laboratory.