Several papers have cited chicken pancreas and dessicated hog kidney as the source for folate conjugase enzyme. 2 ml of this added at a concentration of 5mg/ml. Kariluoto & Piironen (2009) (https://www.sciencedirect.com/science/article/pii/B9781891127700500108)
Some other papers have used fresh blood plasma (rat /human) for the same. If I were to use plasma, what quantity would be needed in the experiment?