Antimicrobial Activity of Acacia Nilotica Bee Honey on Biofilms Forming Staphylococcus aureus isolated from Wound Swabs

Abstract

Bee Honey as an alternative antimicrobial has been explored in the treatment of infections and as a result of its antimicrobial effects had been widely investigated on various microorganisms including biofilms. The formation of biofilm in wounds by pathogenic organisms has been associated with impairment of healing processes due to combined effects of the virulence of organisms within the biofilm. The effect of attenuation of the organism through inhibition of biofilm and quorum sensing (QS) signaling molecules by bee honey will allow the body defense system of the hosts “patients” to easily eliminate the organism from the site of infection. This study was aiming to detect the antibacterial activity of two concentrations of Acacia honey from two different sources on biofilms forming Staphylococcus aureus isolated from wound swabs. The samples were collected from Soba teaching hospital in Khartoum state in the period between June to August 2017. The practical was done in Sudan University of Science and Technology research laboratory on fifty-five Staphylococcus aureus isolated from wound swabs, S.aureus ATCC 29213 and MRSA ATCC 43300. After bacterial isolation the antibacterial activity of benzyl penicillin antibiotic was measured using Kirby Bauer disc diffusion technique. Out of 57 S. aureus 37 (64.9%) isolates sensitive to penicillin, 4 (7%) intermediate and 16 (28.1%) resistant. Activity of Oxacillin disc was measured to detect methicillin sensitivity and there were 51 (89.5%) MSSA and 6 (10.5%) MRSA. The antibacterial activity of bee honey was measured using micro-broth dilution method in 96 well microtiter plate. The two different concentrations of Acacia bee honey 25%, 75% (v/v) and the antibiotics were added and incubated at 37 o C for 24 hours which showed that 25% honey had significant effect in inhibiting S.aureus biofilms (p. value= 0.000) unlike the 75% honey (p. value= 0.075), the benzyl penicillin (p. value= 0.658) and the ceftriaxone (p. value= 0.097) which showed lower effect on biofilm formation. This study concluded that the concentration of Acacia bee honey that affected S.aureus biofilms forming invitro was 25% (v/v). Further studies are needed to evaluate the antimicrobial activity of bee honey.