Environmental disinfection greatly reduces the occurrence of nosocomial or healthcare associated infections (HCAIs) which are the major healthcare problems worldwide. In India, Ayurvedic traditional fumigation with natural plant products is used to disinfect environment. In the present study, environmental disinfection efficiency of traditional fumigation practice has been evaluated by using natural plant products such as garlic (Allium sativum) peel, turmeric (Curcuma longa) powder, Carom (Trachyspermum ammi) seeds (Ajwain) and Loban (resin of Styrax benzoin and Boswellia species). The efficiency of traditional fumigation using these natural products to disinfect air and surface was evaluated. The effect of traditional fumigation on the microbiological quality of air was revealed by active air sampling. In addition, the ability of the traditional fumigation using garlic peel to disinfect inanimate surface was evaluated using three strains of methicillin resistant Staphylococcus aureus (MRSA). Glass slide was artificially contaminated with the bacteria and fumigated whereas non-fumigated slide served as control. The control and fumigated slides were analyzed for surviving bacteria and subjected to scanning electron microscopy (SEM) analysis. Traditional fumigation performed separately with three grams of garlic peel, turmeric, carom seeds and loban powder reduced the average air borne bacterial colony forming units (cfu)/m3 compared to non-fumigated control. The SEM analysis showed reduced number of bacteria in garlic peel fumigated surface samples. The results of the study strongly suggested that the traditional Ayurvedic fumigation with natural plant products is effective in reducing air-borne bacteria and in disinfecting inanimate surfaces. The traditional fumigation with herbal products has huge potential to address the problem of nosocomial infections.
World health organization (WHO) recognizes antimicrobial resistance as a silent pandemic. It is estimated that 10 million deaths will occur annually due to antimicrobial resistant infections by 2050. Phytochemicals exhibit activity against drug resistant bacteria, offering potential for developing novel antibacterial agents. Garlic organosulphur compounds exhibit potent activity against a variety of drug-resistant bacteria. Identifying their mechanism of action is critical to assess their potential to be developed as novel antibacterial agents. Diallyl sulfide (DAS) is a component of garlic essential oil with antibacterial activity. In this study antibacterial activity of DAS was investigated against Bacillus cereus, a common foodborne pathogen. DAS exhibited activity against B. cereus with a minimum inhibitory concentration (MIC) of 54.75 mM. The presence of DAS significantly reduced the growth of B. cereus. The study also investigated the mechanism of antibacterial activity of DAS against B. cereus. Treating B. cereus with sub-MIC and MIC concentration of DAS resulted in a dose and time-dependent leakage of intracellular proteins. The protein leakage was enhanced at acidic pH. Scanning electron microscopy (SEM) of B. cereus treated with DAS showed deformation in the cell membrane. Thus, the data indicate that DAS exerts its antibacterial activity by compromising the membrane integrity of B. cereus. The study demonstrates DAS could be used to control B. cereus infections. The findings indicate that DAS has a membrane altering activity, suggesting that development of resistance to this mechanism is less likely and the compound could be novel antibacterial or a good adjuvant for antibiotics.
8 February 2019 in Indian Journal of Clinical Biochemistry