Chemical Composition, FTIR Studies, Morphological Alterations, and Antifungal Activity of Leaf Extracts of Artemisia sieberi from Saudi Arabia

Artemisia sieberi Besser is an herb widely used in traditional medicine in Middle East to treat various ailments. Present study evaluated various solvent extracts of leaves of A. sieberi growing in Saudi Arabia, against a wide array of phytopathogenic fungi. All the extracts showed significant inhibition. Methanol and dichloromethane extracts showed strong inhibition of mycelial growth of Alternaria alternata, Fusarium moniliforme, F. solani, F. oxysporum and Macrophomina phaseolina. Scanning and transmission electron microscopy of treated fungal cells revealed the damaging effects of extracts on fungi. Scanning electron microphotographs of treated cells show shriveled and twisted mycelium with small vesicles, misshapen and ruptured conidia with heavy scaling and leakage of cell contents. The microphotographs from TEM show heavy vacuolation, proliferation of lipid bodies, septal damage, and undeveloped conidia. GC-MS and FTIR analysis revealed the presence of some important bioactive compounds like Isophorone, Cis-9-Tetradecen-1-ol, Phenol,5-methyl-2-(1-methyl ethyl)-acetate, Phenol, 2-methyl-5 (1-methylethyl), Phenol, 2,4,5-trimethyl, coumarin, camphor, 3-bromo-d-, physostigmine and oxacyclododecen-2-one. The functional groups like phenols, flavonoids, polyphenols, aromatic compounds and ketones were identified from the IR spectrum. The rich and diverse chemical composition of A. seiberi could be responsible for the strong antifungal activity. Hence, leaves of A. sieberi can serve as an ecofriendly substitute for the harmful synthetic fungicides used during harvest and postharvest period. (C) 2019 Friends Science Publishers