Comparative Antifungal and Synergistic Activity of Human, Bovine, Goat and Infant Formula Milk Lactoferrin against Candida albicans, Candida krusei, and Aspergillus terreus

Recently, the extensive use of azole has provoked antifungal resistance, along with the increase prevalence of fungal infections. Milk lactoferrin has been reported to show antifungal activity. This study aims to compare the antifungal activity of lactoferrin in breast milk, cow’s milk, goat’s milk, and infant formula milk with azole against Candida albicans, Candida krusei, and Aspergillus terreus. Lactoferrin samples were extracted from formula milk (fLf), goat’s milk (gLf), cow’s milk (bLf), and breast milk (hLf). Disk diffusion and microdilution techniques were used to assess antifungal activity against wild-type A. terreus, fluconazole-resistant C. albicans ATCC 10231, fluconazole-sensitive C. albicans ATCC 90028, and wild-type C. krusei. Lactoferrin has demonstrated antifungal properties through susceptibility testing. In A. terreus, C. albicans, and C. krusei, bLf generated the biggest zone of inhibition. The antifungal activity produced by bLf and hLf against C. albicans ATCC 90028 was greater than fluconazole (bLf = 32 mm; hLf = 30 mm; fluconazole = 28 mm). In addition, bLf also provides higher zone of inhibition against C. krusei than itraconazole (bLf = 34.44 mm; itraconazole = 31 mm). On microdilution, hLf exhibited the best efficacy against the three fungal strains (MIC of 0.78% for C. krusei wild type, MIC of 1.56% for C. albicans ATCC 10231, and MIC of 0.39% for C. albicans ATCC 90028). Together, azole and lactoferrin had synergistic effect against C. albicans ATCC 10231 and increased antifungal efficacy against C. albicans ATCC 90028, C. krusei, and A. terreus. Bovine and human lactoferrin showed the strongest inhibition compared with other milk lactoferrin, with bovine lactoferrin exceeding fluconazole against fluconazole-sensitive C. albicans and itraconazole against C. krusei. Human lactoferrin exhibited the lowest MICs across species and synergized with fluconazole against resistant C. albicans. These findings suggest that specific milk lactoferrin, particularly bovine and human, may serve as promising antifungal adjuvants.