Safety evaluation of certain food additives
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BIOLOGICAL DATA 2.1 Biochemical aspects No specific absorption, distribution, metabolism or excretion data were available on the galactomannans from cassia gum. However, from studies on guar gum, locust (carob) bean gum and tara gum reviewed by the Committee at its nineteenth, twenty-fifth and thirtieth meetings, respectively (Annex 1, references 39, 57 and 74), it appears that other galactomannans in related gums undergo no or only minimal hydrolysis by digestive juices or enzymes, independent of the specific mannose to galactose ratio. They can be partially fermented by large gut microflora, but are largely excreted unchanged in faeces. The Committee concluded that cassia gum will be largely excreted unchanged as well, although fermentation by gut microflora may occur to some extent. If hydrolysis of cassia gum occurs, the resulting oligosaccharides or monosaccharides would be expected to be absorbed and metabolized in normal biochemical pathways. 2.2 Toxicological studies Most available toxicological studies were performed with semi-refined cassia gum. Semi-refined cassia gum is produced similarly to the cassia gum currently under evaluation, with the exception of an additional isopropanol extraction step to significantly reduce the level of anthraquinones in the latter. Anthraquinones are impurities that occur naturally in the seeds from which cassia gum is produced, some of which may display muscle-toxic, genotoxic or carcinogenic properties. Semi-refined cassia gum contains approximately 70 mg total anthraquinones/kg. 2.2.1 Acute toxicity Two studies of acute oral toxicity were available. In a limit test, five male Wister-Han-Schering rats were given in total 5000 mg semi-refined cassia gum/kg 12 tải về 1.44 Mb. Chia sẻ với bạn bè của bạn:
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