NO PLANT on earth produces useful B-12. Spirulina has "meat" in it in the form of embedded bacteria, and of course Algae are in the plant kingdom, but technically they are not plants. Cyanobacteria (Blue-green Algae): https://en.wikipedia.org/wiki/Cyanobacteria Bacteria and Cyanobacteria can of course make b-12, and eating wet hot compost from a garbage ditch, can keep you supplied with B-12 to prevent retardation. perhaps a few very foul pungent historic forms of pickling may allow enough proper b-12 generating bacteria. Sadly, no normal home made asian pickles not even kimchee have b-12 from plant matter, or bacteria, but from soy sauce addendums.Traditional home-made soybean-fermented foods such as Doenjang, Chungkookjang, and Gochujang were found to contain higher vitamin B12, if rotting for a full 10 months, and no factories ever do that, you would have to rot the material yourself. Tofu has 0.000 B-12 in it, I am talking about breeding colonies of bacteria for b-12. **NO PLANT on earth produces useful B-12.** ========== Spirulina is Cyanobacteria