乳铁蛋白广泛分布于人和哺乳动物乳汁和其他多种组织及其分泌液中（包括泪液、精液、胆汁、滑膜液等内、外分泌液和嗜中性粒细胞），但乳汁中含量较高，其中牛初乳中乳铁蛋白含量最高。血液中乳铁蛋白主要由多核细胞分泌，骨髓、唾液腺及子宫内膜等也能分泌少量乳铁蛋白。

乳铁蛋白来源于人奶的广泛生物学功能决定了其在化妆品、食品、动物生产、医疗等领域中的应用，可作为抗氧化剂、免疫促进剂、补铁剂、药物载体等。

Lactoferrin 17-41 (Lactoferricin B) has an MIC of 30 μg/ml against E. coli ATCC 25922. Lactoferrin 17-41 significantly stimulates apoptosis of HT-29 cells and displays cytotoxic activity on HT-29 cells. Lactoferrin 17-41 variously regulats transcription of genes involved in the p53 signaling pathway, such as PMAIP-1, TP5313, and SFN. Lactoferrin 17-41 can bind LPS from Gram-negative bacteria and that it can inhibit LPS induced cytokine response in human monocytic cells. Cell Viability Assay Cell Line: HT-29 cells Concentration: 50, 100, 200, 400, 800 or 1000 µg/mL Incubation Time: 4, 12, 24 or 48 hours Result: More effective at inducing apoptosis at 400 µg/mL. Higher toxicity is shown at 800 µg/mL.

Lactoferrin 17-41 (Lactoferricin B) 对应于牛乳铁蛋白的残基 17-41，对革兰氏阳性和革兰氏阴性细菌、病毒、原生动物和真菌等多种微生物具有抗菌活性。Lactoferrin 17-41 具有抗肿瘤活性。