Phytochemical Analysis and Antifungal Activity of Fruit Leaves Extracts on the Mycelial Growth of Fungal Plant Pathogens

Methanolic extracts of leaves of thompson seedless grape, flame seedless grape, zizyphus, pomegranate and fig were screened for their phytochemical constituents and also investigated for their antifungal activity in vitro against phytopathogenic fungi, Alternaria solani, Botrytis cinerea, Botrytis fabae, Fusarium oxysporum and Fusarium solani. Phytochemical screening of crude methanolic extracts revealed the presence of terpenes, tannins, flavonoids, alkaloids, carbohydrate or glycosides, phenolic glycosides and resins in all extracts, while saponins were not detected from any extracts except zizyphus and fig. Zizyphus leaves had the highest concentration of total polyphenols and total flavonoids content which were 147.47 mgGAE/g and 16.35 mgQE/g, respectively. HPLC analysis identified twelve polyphenolic compounds; pyrogallic acid, gallic acid, protocatechuic, catechin, p-hydroxy benzoic acid, p-coumaric acid, phenol, o-coumaric acid, salicylic acid, coumarin, quercetin and cinnamic acid. All extracts contained protocatechuic, catechin, p-hydroxy benzoic acid, p-coumaric acid, o-coumaric acid and coumarin with different concentrations. The methanolic extract of zizyphus leaves had the greatest inhibitory effect on mycelial growth of B. fabae by 95.56% at 4 mg/ml. Also, extract of pomegranate caused remarkable reduction on the fungal growth (94.44%) of B. fabae at 4 mg/ml, while fig extract caused 91.11% inhibition against the same fungus at the same concentration. F. oxysporum and F. solani were the most resistant fungi against all methanolic extracts tested