Mo-CBP4, a purified chitin-binding protein from Moringa oleifera seeds, is a potent antidermatophytic protein: In vitro mechanisms of action, in vivo effect against infection, and clinical application as a hydrogel for skin infection.

Dermatophytes belonging to Trichophyton ssp. are important anthropophilic and zoophilic pathogens, which developed resistance to griseofulvin, the common antifungal drug used to treat dermatophytosis. In this context, Moringa oleifera seed proteins have been described as antifungal agents with potential applications. Thus, this work aimed to evaluate the antidermatophytic in vitro, focusing on mechanisms, and in vivo potential of Mo-CBP4, purified from M. oleifera seeds. Mo-CBP4was purified after protein extraction with 50 mM Tris-HCl buffer, pH 8.0, and chromatography on chitin and CM Sepharose™ columns and antidermatophytic potential of Mo-CBP4 evaluated in vitro and in vivo. In vitro, Mo-CBP4 reduced in 50% the germination of microconidia of Trichophyton mentagrophytes at 45 µM; but did not show inhibition of mycelial growth. Mo-CBP4 (45 µM) presents the inhibitory activity even when incubated with N-acetyl-d-glucosamine (NAG). Analysis of the mechanisms of Mo-CBP4 revealed an increase in membrane permeability, ROS overproduction and damage to cell wall leading to microconidia death. Furthermore, using in vivo models, Mo-CBP4 (5, 10 and 20 mg g-1) reduced the severity and time of dermatophytosis. Altogether, these findings indicate that Mo-CBP4 has great potential for the development of novel antifungal drugs for the clinical treatment of dermatophytosis.

Role of membrane sterol and redox system in the anti-candida activity reported for Mo-CBP2, a protein from Moringa oleifera seeds.

Plant proteins are emerging as an alternative to conventional treatments against candidiasis. The aim of this study was to better understand the mechanism of action of Mo-CBP2 against Candida spp, evaluating redox system activity, lipid peroxidation, DNA degradation, cytochrome c release, medium acidification, and membrane interaction. Anti-candida activity of Mo-CBP2 decreased in the presence of ergosterol, which was not observed with antioxidant agents. C. albicans treated with Mo-CBP2 also had catalase and peroxidase activities inhibited, while superoxide dismutase was increased. Mo-CBP2 increased the lipid peroxidation, but it did not alter the ergosterol profile in live cells. External medium acidification was strongly inhibited, and cytochrome c release and DNA degradation were detected. Mo-CBP2 interacts with cell membrane constituents, changes redox system enzymes in C. albicans and causes lipid peroxidation by ROS overproduction. DNA degradation and cytochrome c release suggest apoptotic or DNAse activity. Lipid peroxidation and H+-ATPases inhibition may induce the process of apoptosis. Finally, Mo-CBP2 did not have a cytotoxic effect in mammalian Vero cells. This study highlights the biotechnological potential of Mo-CBP2 as a promising molecule with low toxicity and potent activity. Further studies should be performed to better understand its mode of action and toxicity.