Use of an ultrasound cell retention system for the size fractionation of somatic embryos of woody species

The Effect of Megasonic Separation on the Nutritional and Physical Properties of Food - An Overview

“…For example, no significant damage to blood cells was reported at frequencies between 0.5 to 3.5 MHz with the exception of cases where excessive power caused cavitation at frequencies below 1 MHz [26]. Similarly, Maitz et al [27] also demonstrated no significant alteration to physical integrity of plant cells when subject to ultrasonic separation.…”

The Uses Of Ultrasound In Plant Tissue Culture

“…powerful tunable instruments emitting via "horns" (e.g. [14]), commonly used for tissue disruption, or by laboratory-produced equipment [23]. Soyabean, cowpea, maize, wheat, Ohio buckeye -various tissues SAAT* 55 kHz/ 0.2-100s/50W/10-20 × 2-4 mm clumps in 1 ml in 13×100 mm glass tube [15] Soyabean embryogenic callus SAAT* 55 kHz/ 0-300s/50W/10-20 × 2-4 mm clumps in 1 ml in 13×100 mm glass tube [16] Soyabean immature embryos SAAT* 55 kHz/ 0.1-10s/50W /10 cots in 0.5 ml in 1.5 ml microfuge tube [17] Soyabean cotyledonary nodes SAAT* 55 kHz/6-600s/50W/10 explants covered in Agrobacterium solution in 16×125 mm glass tube [18] Ohio buckeye SAAT* 55 kHz/ 0-60s/50W /10 embryogenic clumps in 1 ml in 13×100 mm glass tube [19] Robina pseudoacacia cotyledon SAAT* 30 kHz/ 60s/ 60 W /10 explants in 20 ml in 50 ml Falcon tube [20] Squash cotyledon explant multiple shoot regeneration 47 kHz/ 30-120s/ 35W/ 20 explants (420 mg) in 10 ml in 25×150 mm glass tube [21,22] Ultrasound can be supplied as a continuous waveform, or as pulses, propagating wave or standing wave, a fact little discussed in the literature of plant tissue culture.…”

“…Mature embryos of different species were sorted using purpose-built equipment operating at a higher frequency than reported in Table 1 (carrot embryos at 190 kHz in pulses at 0.5-1.5W; the larger tree embryos at 175 kHz in pulses at 0.7W). The embryos were sorted by size, using an ultrasound standing wave to trap cells in a flow-through system, as the particles are much smaller than the acoustic wavelength used [23]. As the embryos were about 1 mm in size, an acoustic wavelength of about 7 mm was used to trap the embryos at the antinodes of the sound velocity field, where there is less acoustic energy, and they are not damaged by acoustic forces [23].…”

“…Ultrasound was used to breakup embryo clusters and then to fractionate effectively somatic embryos of carrot (Daucus carota), cork oak (Quercus suber), grapevine (Vitis berlandieri × rupestris), and cherry (Prunus incisa × serrula) [23]. Mature embryos of different species were sorted using purpose-built equipment operating at a higher frequency than reported in Table 1 (carrot embryos at 190 kHz in pulses at 0.5-1.5W; the larger tree embryos at 175 kHz in pulses at 0.7W).…”

“…The embryos were sorted by size, using an ultrasound standing wave to trap cells in a flow-through system, as the particles are much smaller than the acoustic wavelength used [23]. As the embryos were about 1 mm in size, an acoustic wavelength of about 7 mm was used to trap the embryos at the antinodes of the sound velocity field, where there is less acoustic energy, and they are not damaged by acoustic forces [23]. In this flow-through system, smaller embryos and cells which had not differentiated sufficiently were not trapped, and passed through for resorting [23].…”