Could some of the USP vitamin D remain in the batch, without being
metabolized by the yeast?
One may question how we know that, at the end of the growing process, none of the USP vitamin D3 is left in its original, non-grown or non-renatured state. There are analytical tests that verify this fact. These tests are performed on every lot of renatured vitamin D we manufacture.
The first analytical test is performed using High Performance Liquid Chromatography (HPLC) equipment. To demonstrate the efficacy of this test, one must first understand that all vitamin D is fat soluble. All vitamins are either fat soluble, meaning they dissolve in fats, or water soluble, indicating that they dissolve only in water. And as we learn in grade school science, fat and water never mix. Therefore, to test for the presence of fat soluble vitamins, the lab must first wash whatever is being tested with alcohol. Alcohol will cause the fat soluble components present to separate from the rest of the medium.
In this case, we wash the high Vitamin D yeast with ethanol. The yeast is then separated and dried. The remaining ethanol is collected for analysis. If the HPLC test reveals any fat soluble substance present within the yeast, then we know that USP vitamin D is present and the yeast has not fully metabolized, and converted all of the vitamin D. That entire batch of yeast would then be discarded. [In the decades we’ve been growing renatured Vitamin D through our process, we’ve had to discard very few batches of yeast.]
Our second test is performed once the ethanol wash is complete and we have verified that the only vitamin D remaining is yeast cell. The yeast-bound vitamin D is then subjected to HPLC analysis that actually breaks the cell wall. This time we are looking for the presence of Vitamin D inside of the yeast cell. In order to extract the vitamin D from the inside of the yeast cell we must first break the yeast cell wall during the sample preparation phase. After the cell wall of the yeast is broken we can then perform the analysis for the presence of vitamin D through another ethanol wash. This second analysis confirms that the potency of the vitamin D achieves the specification required for the production of our encapsulated products.
Finally, the most plant-like attribute of the final product are the co-factors present in all plant forms of food but not present in synthetic vitamins. These co-factors include: antioxidants, glycoproteins, lipoproteins, glutathione, CoQ10 and SOD (superoxide dismutase). We never add these co-factors; they are endogenous to the yeast cells. Just as plants contain a variety of food components (proteins, carbohydrates and fats) that surround the vitamins in the plant the renatured vitamin D maintains nutrients that mimic the characteristics of plants. With the presence of these co-factors the renatured vitamin D is ready for use in our vegan friendly supplements.
Through this painstaking and careful process we can now make Vitamin D3, a vital nutrient, available in a vegan-friendly format for supplementation.