Characterization of Vitamin B12 Compounds in Fermented Poultry Manure Fertilizers

(1) Background: Currently, no data are available on the vitamin B12 content of an organic fertilizer product, viz. fermented poultry manure, or whether the organic fertilizer product contains vitamin B12 or inactive corrinoids (or both). (2) Methods: This study conducted a microbiological assay to determine the vitamin B12 content of various commercially available fermented poultry manure fertilizer products. (3) Results: The results varied from 1.4 μg to approximately 20 μg per 100 g of dry weight. In the bioautography analysis, selected products had two positive spots with identical Rf values of vitamin B12 and pseudovitamin B12. High-performance liquid chromatography and liquid chromatography/electrospray ionization−mass spectrometry analyses of the selected products indicated that these fertilizers primarily contained vitamin B12. They also contained minor inactive cobamides such as pseudovitamin B12, 2-methyladenyl cobamide, and 2-methylmercaptoadenyl cobamide. (4) Conclusions: These results suggested that edible plants would enrich vitamin B12 using fermented poultry manure organic fertilizer products.