Safety evaluation of Lactobacillus plantarum strain TWK10® isolated from Taiwan Pickled Cabbage

Abstract

In recent years, probiotics have drawn increasing attention due to their ability to confer multiple health benefits. It is vital to evaluate the safety of a probiotic strain, to confirm it is safe and well-tolerated by human. Lactobacillus plantarum TWK10®, isolated from Taiwanese pickled cabbage, has been demonstrated to have beneficial effect on improving exercise performance and muscle mass in clinical studies. In this study, we evaluated the safety of TWK10 in a battery of animal and in vitro studies including oral toxicity, the Ames' bacterial reverse mutation assay, the mammalian micronucleus and chromosome aberration tests. A subacute repeated-dose 28-day toxicity study was conducted to determine the no observable adverse effect level (NOAEL) of TWK10. In Ames' test, the results showed no mutagenic effect of TWK10 with or without the addition of S9 mixture. The mammalian chromosomal aberration test conducted in Chinese hamster ovary cells (CHO-K1) showed TWK10 was not genotoxic. Additionally, TWK10 administration did not cause any significant change in reticulocyte ratio and micronucleus incidence in ICR mice suggesting that it is non-mutagenic. In the repeated dose 28-day subacute oral toxicity study, SD rats administered with TWK10 at 1.4 × 1010, 2.8 × 1010 and 5.6 × 1010 cfu/kg/day showed no clinical signs of toxicity or adverse effects. Based on these findings, the NOAEL of TWK10 was determined to be 5.6 × 1010 cfu/kg/day. These findings combined with the tolerability seen in human clinical studies suggests that TWK10 is safe for human consumption.