Exploring Agave americana L. as a Promising Alternative for Dermatophytosis Management

Abstract

The role of traditional medicine in South Africa has altered drastically in the past few decades. This could be a result of colonization and westernisation of culture. Poor lifestyle choices including grooming and diet lead to compromised immune systems. Consequentially, the body becomes vulnerable to recuring illnesses and susceptible to numerous skin infections including fungal infections. The folkloric use of medicinal herbs in the treatment and management of dermatological conditions is well documented. Folkloric medicine has been shown to possess some of the best biological and/ or antipathogenic activities. However, some of these activities are yet to be validated and/ or documented. Therefore, a wide literature search was executed to bring to the fore, some of the dermatologically significant medicinal plants that are utilised by the Sotho speaking people of Bloemfontein with a view to select an understudied species for further studies. Agave americana L. was thus selected for further studies. Some South African companies use this plant in the production of skin care products, indicating its potential commercial significance. However, the plant is classified as a category three invasive species in South Africa, posing a threat to local ecosystems. Utilizing the plant for dermatological purposes can offer a dual benefit by addressing prevalent skin conditions in the population and controlling the spread of the invasive species. To minimize ecological impact, it is suggested to promote the controlled utilization of the plant. Exploring the dermatological effects of Agave americana L. not only contributes to scientific knowledge but also validates and preserves traditional practices. This research has the potential to bridge the gap between traditional wisdom and modern science, providing effective skincare solutions while addressing ecological concerns related to the plant's invasive nature. Agave americana L. growing in Bloemfontein was profiled for secondary metabolites using LC-MS techniques. The samples were collected near Bloemdustria in Bloemfontein, Free State South Africa, at a height of approximately 1395m above sea level on the Old Thaba Nchu Road. Two triterpenoids, including Piscidic and Eucomic acid and a glycoside, were profiled and identified. This plant is thus potentially rich in terpenes. Terpenes are well recognized for their ability to promote transdermal absorption and possess anti-inflammatory qualities, in addition to other physiological roles in humans. Because of their unique chemical structures and the tissues or organs they interact with, glycosides have a variety of roles. Although a host of other secondary metabolites could not be identified for various reasons, these results could be more promising. Perhaps essential oil extracts can potentially reveal other secondary metabolites that can then be linked to their supposed medicinal properties and therefore validate this plant’s use in folkloric medicine. The study analysed the potential of Agave americana L. acetone, methanol, and water extracts in treating dermatological infections in somatology. The extracts were therefore assayed for biological activities including antioxidant (FRAP and DPPH), anti-and-pro-inflammatory as well as antifungal activity (against C. albicans, T. interdigit, T. rubrum and T. tonsurans). The water extract showed the most potential, followed by methanol and acetone extracts. The water extract showed the most activity, with concentrations of 250 and 500 μg/ml being more active than Trolox and EGCG. The acetone extract was inactive, while methanol was active but not significantly different. The water extract showed the best potential for DPPH scavenging, with IC50 values between 15.625 and 31.25 μg/ml. The water extract showed pro-inflammatory activity, with high concentrations of nitrite at low extract concentrations, which decreased in a dose-dependent manner. None of the extracts exhibited anti-inflammatory potential. The study also found that C. albicans, T. interdigit, T. rubrum, and T. tonsurans were resistant to all dilutions tested. This study therefore can conclude that the Agave americana L. did not possess any antifungal activity against the tested pathogens. This is also not very surprising considering the very low secondary metabolites constituents as reported in chapter 3. The genotoxicity and cytotoxicity of Agave americana L. leaf extracts on the kidney cell line (Vero cells) in-vitro were assayed using standard methods. The study found that acetone and water extracts did not increase micronuclei formation at all concentrations except for 200 μg/ml. However, the methanol extract showed an increase in micronuclei formation, indicating potential genotoxicity. The water extract showed mild toxicity against Vero cells, with an estimated IC50 value of 200 μg/ml. However, these results are negligible as they are below the minimum concentration required to inhibit biological response. Due to some indications of toxicity, further studies are therefore recommended.