Study of the Effect of Aloe vera Gel, Neem Leaf and Licorice Extracts in Controlling Aspergillus Niger in Mazafati Rutab

In this study, inhibitory effects of herbal products (licorice root and neem leaf extracts, Aloe vera gel) on Aspergillus niger growth isolated from Mazafati palm dates and control of this mold in Mazafati palm dates were studied. The mold was isolated from rotten Mazafati palm dates. Herbal products were added to melted potato dextrose agar medium in different concentrations (0.1, 0.5 and 1% for Licorice root and neem leaf extracts and 0.25, 0.35 and 0.50% for Aloe vera gel). Plates containing the herbal products were inoculated with fungi discs (7mm diameter) and incubated at 25°C ± 1. The diameter of fungus colonies (mm) were measured daily. There was significant difference (P < 0.01) among the herbal extracts and also their concentrations in preventing Aspergillus niger growth. The results showed that inhibitory effects of licorice root extract on Aspergillus niger growth were significantly more than that of neem extract and Aloe vera gel. High concentration of the extracts had also more inhibitory effects on the mold growth. The licorice root extract at 1% concentration showed more reduction in the growth of Aspergillus niger and also was effective on control of rot in Mazafati palm dates. The licorice root extract did not make any special taste in Mazafati palm dates and obtained the more score in the sensory attributes (taste, appearance, acceptability).