本研究的目的是探讨本土乳酸菌发酵乳清液，包括Lactobacillus helveticus KMCH1（ON561781）、Lactococcus lactis KMCM3（ON561782）和Lactiplantibacillus plantarum KMJC4（ON615217）对人结肠癌（HT-29）和正常小鼠成纤维细胞（L929）体外细胞的影响。本研究利用蛋白酶活性、MTT测试、细胞凋亡诱导和细胞周期阻滞流式细胞术进行了实验检测。利用OPA试剂测量三种不同类型的发酵乳清液的蛋白酶活性，结果表明L. helveticus KMCH1发酵乳清液具有最高的蛋白水解作用。三种类型的发酵乳清液在时间和浓度上呈现出对HT-29细胞的抗癌效果（浓度为16 mg ml-1，在72小时内），而对L929细胞抑制效果为3%至10%。此外，这三种多种细胞液体被证明通过诱导细胞凋亡和S期细胞周期阻滞抑制了HT-29细胞的增殖。本土乳酸菌株能够在发酵乳中产生具有抗癌效果的生物活性肽。抑制HT-29细胞增殖取决于肽的浓度。© 作者（2023）。由牛津大学出版社代表应用微生物国际公开发布。

The purpose of this study was to investigate the effect of fermented milk supernatants of autochthonous lactic acid bacteria including; Lactobacillus helveticus KMCH1 (ON561781), Lactococcus lactis KMCM3 (ON561782) and Lactiplantibacillus plantarum KMJC4 (ON615217) on human colon cancer (HT-29) and normal mouse fibroblast (L929) cells in vitro.Proteolytic activity, MTT test, evaluation of apoptosis induction and cell cycle arrest by Flow Cytometry were the assays performed in this study. The measurement of proteolytic activity of three types of fermented milk supernatant using OPA reagent showed that fermented milk supernatant of L. helveticus KMCH1 included the highest proteolysis. Three types of fermented milk supernatant showed anticancer effect on HT-29 cell in a time- and concentration-based manner (at a concentration of 16 mg ml-1 for 72 h), while the effect of three types of supernatant on inhibition of L929 cell was 3 to 10%. Besides, three types of supernatant inhibited HT-29 cell proliferation by inducing apoptosis and cell cycle arrest at S phase.Autochthonous lactic acid bacteria strains were able to produce bioactive peptides with anticancer effects in fermented milk. Inhibition of HT-29 cell proliferation was dependent on peptide concentration.© The Author(s) 2023. Published by Oxford University Press on behalf of Applied Microbiology International.