For plant leaf samples rich in polysaccharides and polyphenols, which DNA extraction kit has a fast lysis speed?

Complete grinding-free processing is not very realistic for samples such as pine needles. Due to the waxy leaf surface and thick cell walls, direct lysis usually results in highly variable yields. A more feasible approach is "semi-grinding-free": cut the leaves into 2-3 mm small pieces, place them into a 96-well deep-well plate, add lysis buffer and steel beads, and shake using a high-throughput tissue grinder. In this way, more than 100 samples can be processed per day. When selecting a kit, ask clearly whether it is tolerant to high concentrations of polysaccharides and polyphenols. Some kits add a high-salt/chloroform extraction step before binding; although this adds one more step, it significantly improves purity. There are also magnetic bead methods that rely on a special binding buffer to directly bind DNA, avoiding organic solvents and making them suitable for automation. If the price is within 15 yuan/sample, it is advisable to negotiate bulk packaging or group purchasing. If purity is unstable, do not switch entirely at first; use 20 samples for a parallel comparison.

For over 100 plant samples per day, it is recommended to abandon traditional manual CTAB and directly use a 96-well plate magnetic bead method or column-based high-throughput plant DNA kit. Rice leaves are relatively easy to extract, but pine needles contain high levels of polysaccharides and polyphenols. When selecting a kit, check whether the lysis buffer contains CTAB/guanidine salts and high-concentration salts, and it is best if PVP or β-mercaptoethanol can be added to prevent browning. The key to rapid lysis is using a tissue grinder: use deep-well plates with 2-3 3 mm steel beads, add lysis buffer, and run on the instrument for 60-120 seconds to disrupt the tissue, which is much faster than liquid nitrogen grinding. For the extraction steps, choose a magnetic bead method that is directly compatible with 96-well plates, with an elution volume of 50-100 μL; a batch of 96 samples takes about 1.5-2 hours. Within a budget of 15 RMB/sample, domestic bulk packaging or OEM has a chance to achieve this, while imported bulk may exceed it. It is recommended to first request trial runs with 24 rice and 24 pine needle samples each, and check A260/A280 and A260/A230.

A budget of 15 yuan/sample is tight for plant genome extraction, but not impossible, especially for domestic bulk packaging of 96-well plate magnetic bead methods, where the per-sample cost can be in the 10-20 yuan range, depending on whether magnetic rod sleeves and deep-well plates are included. When comparing prices, have suppliers provide test data for rice leaves and pine needles separately, rather than looking at only a single material; some kits perform very well on rice, while for pine needles the 260/230 ratio can drop below 1.4. You can ask suppliers whether they can provide a chloroform-free/organic solvent-free version, which makes high-throughput workflows smoother. More importantly, first try small packaging; many manufacturers can provide 2-4 plates for trials, using the same batch of samples to run a CTAB control in parallel, and tallying yield, purity, and PCR success rate. If purity is poor, you can additionally add 5-10 mg PVP during lysis or increase the centrifugation speed, but this will lengthen the time. Choose suppliers that can provide 96-well plate centrifugation/magnetic rack adaptation solutions to reduce manual plate changing.

The lysis time for polysaccharide- and polyphenol-rich samples was too long. We tried both yellow flower and leaf samples, and finally found that adding PVP had a significant effect.

Is there a rapid protocol that does not require liquid nitrogen grinding? With a large number of samples, manual grinding is too slow.