No abstract

Arabinase is an enzyme recognized for its ability to degrade arabinan, a plant cell wall constituent. It has been applied in the food industry most commonly for juice processing. One commercial source of arabinase is Aspergillus tubingensis (A. tubingensis), a black Aspergillus species. Given the intended use in food for human consumption, and noting its potential presence at trace levels in finished products, a series of safety studies including in vitro Ames and chromosome aberration assays, in vivo mammalian erythrocyte micronucleus and alkaline comet assays, and a 90‐day rat oral toxicity study were conducted. No test article‐related mutagenic activity was observed in the Ames assay. Although positive activity was observed in the chromosome aberration assay, this was not replicated in the in vivo genotoxicity assays including in preabsorptive cells. In the subchronic toxicity study, no test article‐related adverse effects were observed following oral administration of arabinase at doses of 15.3, 153, or 1,530 mg total organic solids (TOS)/kg body weight/day to Sprague Dawley rats. The no‐observed‐adverse‐effect level was considered to be the highest dose tested (1,530 mg TOS/kg body weight/day). The results of the genotoxicity studies and the subchronic toxicity study support the safe use of arabinase from A. tubingensis in food production.

Isomaltodextrin-producing enzymes (PP enzyme) include two extracellular enzymes (α-glucosyltransferase and α-amylase) produced by Paenibacillus alginolyticus PP710. These enzymes are essential for producing isomaltodextrin (IMD), a highly branched α-glucan, from starch. In this study, we evaluated the safety of this PP enzyme. No genotoxicity was observed when the PP enzyme was assayed in standardized bacterial reverse mutation and chromosome aberration tests. An acute toxicity study in rats showed no toxic effects of PP enzyme at 2,000 mg/kg. No animals died, and no effects of enzyme administration were observed in a 14-day repeated oral-dose toxicity study in rats at the maximum dose of 1,000 mg/kg/day. The no observed adverse effect level was determined to be 1,000 mg/kg/day in a 90-day subchronic gavage toxicity study in rats. No animals died, and no abnormal findings due to consumption of the PP enzyme were observed in this study. These safety evaluation results demonstrated that the PP enzyme was safe for application as an ingredient in the manufacturing of the food ingredient IMD.