Allicin extract exhibits anti-group B streptococci activity. - GreenMedInfo Summary
In vitro activity of an aqueous allicin extract and a novel allicin topical gel formulation against Lancefield group B streptococci.
J Antimicrob Chemother. 2009 Jan;63(1):151-4. Epub 2008 Nov 11. PMID: 19001449
University of East London, Romford Rd, Stratford, London E15 4LZ, UK. [email protected]
BACKGROUND: Studies have shown the efficacy of intra-partum antibiotics in preventing early-onset group B streptococcal sepsis. This approach results in a high intra-partum antibiotic use. Worryingly, the same antibiotics used in prophylaxis are also first-line treatment for neonatal sepsis, and antibiotic exposure in the peri-natal period has been shown to be a risk factor for late-onset serious bacterial infections and allergic disease. Antibiotic exposure in the peri-natal period is becoming a major public health issue; alternative strategies are needed. Garlic has been traditionally used to treat vaginal infections. Allicin is the main antibacterial agent isolated from garlic.
OBJECTIVES: The aim of the study was to investigate the in vitro activity of a novel allicin extract in aqueous and gel formulation against 76 clinical isolates of Lancefield group B streptococci (GBS).
METHODS: MICs and MBCs of allicin were determined for 76 GBS isolates by agar dilution and microtitre plate methods. Killing kinetics were determined for a selected 16 of the 76 strains. Agar diffusion tests were compared for allicin liquid and gel (500 mg/L).
RESULTS AND CONCLUSIONS: MICs and MBCs of allicin liquid were 35 to 95 mg/L and 75 to 315 mg/L, respectively. Time/dose kill curves produced a 2-3 log reduction in cfu/mL within 3 h and no detectable growth at 8 and 24 h. A novel 500 mg/L allicin gel produced an average zone size of 23+/-6 mm compared with 21+/-6 mm for allicin in water. Aqueous allicin is bactericidal against GBS isolates and maintains activity in a novel gel formulation.
