Antimicrobial activity of aloe vera, citrus hystrix and zingiber officinale against fungus pyricularia oryzae and bacteria bacillus subtilis

Abstract

Rice blast disease is caused by the seed-borne pathogenic fungus known as Pyricularia oryzae. Rice blast disease which attacked the paddy plants has become an important and serious disease nowadays which it caused the reducing in rice yield to 50 % worldwide. The current study was developed to prevent the rice blast disease from damaging the paddy plants. In this project, P.oryzae fungus and bacteria of Bacillus subtilis was used for testing the antifungal and antibacterial activity. The leaf and grain part of the paddy plant was taken and isolated and their morphology was observed and measured. The fungus was identified from its pattern on PDA which looks like white colony colour, fluffy, round and the pear-shaped of its conidia. Antifungal activity was demonstrated by using three different concentrations (10, 20 and 30 mg/ml) of ethanol extract of three different plants which are Aloe vera, Citrus hystrix and Zingiber officinale. A.vera has the highest antifungal activity effect against P.oryzae at concentration of 30 mg/ml followed by Z.officinale and C.hystrix. Antibacterial activity against the bacteria of B.subtilis, was demonstrated by using disc diffusion method with four different concentrations (5, 10, 20 and 30 mg/ml) of the three plant extracts. The highest antibacterial activity was shown by the extraction of A.vera at concentration of 30 mg/ml followed by Z.officinale and C.hystrix extraction at concentration of 20 mg/ml. Minimum Inhibitory Concentation (MIC) was at the lowest concentration of both antifungal and antibacterial activity. In a conclusion, the extraction of A.vera, C.hystrix and Z.officinale has shown the ability as an antifungal and an antibacterial agent against the fungus and bacteria.