title: Development of a rapid and simple method for detection of protein contaminants in carmine.
abstract: Protein contaminants in carmine can cause dyspnea and anaphylactic reactions in users and consumers of products containing this pigment. The method generally used for detection of proteins in carmine has low reproducibility and is time-consuming. In this study, a rapid, simple, and highly reproducible method was developed for the detection of protein contaminants in carmine. This method incorporates acidic protein denaturation conditions and ultrafiltration. To prevent protein aggregation, sodium dodecyl sulfate containing gel electrophoresis running buffer was used for dispersing the carmine before filtration. An ultrafiltration device was used to separate the protein contaminants from carminic acid in the carmine solution. Two ultrafiltration devices were compared, and a cylindrical device containing a modified polyethersulfone membrane gave the best results. The method had high reproducibility.
authors.affiliation: Graduate School of Environmental Symbiotic System and Department of Innovative Systems Engineering, Nippon Institute of Technology, 4-1 Gakuendai, Miyashiro-machi, Saitama 345-8501, Japan.
authors.forename: Norihisa
authors.initials: N
authors.lastname: Nakayama
authors.affiliation: Kishi Kasei Company, 1-10-8 Fukuura, Kanazawa-ku, Yokohama 234-0004, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Ohtsu
authors.affiliation: Kishi Kasei Company, 1-10-8 Fukuura, Kanazawa-ku, Yokohama 234-0004, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Maezawa-Kase
authors.affiliation: Graduate School of Environmental Symbiotic System and Department of Innovative Systems Engineering, Nippon Institute of Technology, 4-1 Gakuendai, Miyashiro-machi, Saitama 345-8501, Japan.
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Sano