1. 1) List of Existing Food Additives (List of food additives from natural origin compiled and published by the Ministry of Health and Welfare on April 16, 1996): The Ministry of Health and Welfare Announcement, No. 120, Tokyo, Japan.
2. 2) Tanaka, O., Tamura, Y., Masuda, H., Mizutani, K., Application of saponins in foods and cosmetics: saponins of Mohave Yucca and Sapindus mukurossi. Adv. Exp. Med. Biol., 1-11 (1996).
3. Spectrophotometric Determination of Saponin in Yucca Extract Used as Food Additive
4. 4) Blunden, G., Hardman, R., Quantitative estimation of monohydroxy saturated steroidal sapogenins in plant materials by densitometric thin-layer chromatography. J. Chromatogr., 34, 507-514 (1968).
5. 5) Budzikiewicz, H., Djerassi, C,. Williams, D. H., Structure elucidation of natural products by mass spectrometry, Volume II: Steroids, terpenoids, sugars, and miscellaneous classes. Holden-Day, Inc., 1964, p. 112-113.