19. Antibacterial and antifungal activities of extracts of Convolvulus leiocalycinus and Haloxylon griffithii of Balochistan, Pakistan

Abstract

Different medicinal plants have the potential of antibacterial and antifungal activities. Therefore, this research was executed to assess the antibacterial and antifungal activities of different fractions i.e. water (H₂O), chloroform (CHCl₃), n-hexane (C₆H₁₄) and ethyl acetate (C₄H₈O₂) of Convolvulus leiocalycinus and Haloxylon griffithii by applying Agar well diffusion method. Bacterial strains of four types i.e., 3 gram-negative and 1 gram-positive namely Escherichia coli, Klebsiella pneumonia, Staphylococcus aureus, Pseudomonas aeruginosa and a fungal strain like PBF-1 were used to investigate the antibacterial and antifungal activities in the selected plant extracts. The water, chloroform, ethyl acetate and n-hexane fractions of C. leiocalycinus exhibited antibacterial activities of 7, 7, 7 and 6mm zone of inhibition respectively against S. aureus bacteria. Consequently, the same four fractions of H. griffithii displayed antibacterial activities against S. aureus 8, 8, 9 and zero mm zone of inhibition respectively. Considering the antifungal activity, the ethyl acetate fraction of C. leiocalycinus showed strong inhibition i.e., ++. But in H. grifithii, only the n-hexane fraction gave partial inhibition in antifungal activity. These results indicated that the ethyl acetate fraction of C. leiocalycinus exhibited strong antifungal activity as compared with the same fraction of H. griffithii showing that C. leiocalycinus is more potent as compared to H. griffithii. This justifies the usage of both plants in traditional medicines in future. It is also suggested that the use of entire extract of both the plants in foods can improve their shelf life.

Keywords: Agar well diffusion; Antibacterial activity; Antifungal activity; fungal strain PBF-1.

http://dx.doi.org/10.19045/bspab.2019.80175