Profiling of phytochemicals and evaluation of antifungal activity of Piliostigma species on Aspergillus species causing tomato fruit rot

Abstract

Abstract. Mahmud AA, Danladi MD, Adi BA, Abdulrahman MD, Nafi’u BS, Mohammed UA. 2023. Profiling of phytochemicals and evaluation of antifungal activity of Piliostigma species on Aspergillus species causing tomato fruit rot. Asian J Trop Biotechnol 20: 62-68. Medicinal plants, such as Piliostigma reticulatum (DC.) Hochst. and Piliostigma thonningii (Schumach.) Milne-Redh. from the family Fabaceae are considered therapeutic due to the bioactive compounds present in their organs. These medium-sized, leguminous trees, native to the tropics and common in Nigeria, are rich in antifungal and antioxidant compounds. The study focused on the phytochemical components of these plants and evaluation of antifungal activity which was tested against Aspergillus fungi species isolated from rotten tomatoes. Identification and quantification of the plants’ phytochemical constituents of ethanolic and aqueous extracts were conducted, assessing the antifungal activity of the extracts and determination of the extracts Minimum Fungicidal (MFC) and Inhibitory Concentrations (MIC). From the study, these extracts contained biologically active compounds, including alkaloids, flavonoids, tannins, saponins, cardiac glycosides, and anthraquinones. The inhibitory effect of the ethanolic extracts ranged between (4-42mg/mL) and (5-31mg/mL) for Aspergillus niger and Aspergillus fumigatus, respectively. While aqueous extracts was recorded (6-20mg/mL) and (7-15mg/mL). The MIC values of ethanolic extracts have (6-8mg/mL) and (7-26mg/mL), and MFC values of (28-30mg/mL) and (22-28mg/mL) against A. niger and A. fumigatus. The aqueous extracts have MIC values (32-38mg/mL) and (36-59mg/mL), MFC values ranged (50-56mg/mL) and (38-65mg/mL) against A. niger and A. fumigatus, respectively. The study has shown that the plant extracts contained antifungal properties based on bioactive compounds found in their leaves and antifungal effects demonstrated against the tested organisms. The findings suggest the use of these plant extracts, which could serve as potential bio-fungicides when explored further. The study of the bioactive compounds of these plants provides a foundation for creating natural, safer medications and innovative bio-fungicide products. Subsequent investigations on the specified plants will be based on the framework established by this study. Future research, including in vivo testing and exploration of the mechanism of action, is recommended.