IN-VITRO EVALUATION OF DISINFECTANTS AGAINST INDIGENOUS ASPERGILLUS PARASITICUS

Abstract

Fungal spores are present in environment of food industry, indoor environment, hospitals, pharmaceutical industry and vaccine production units. These fungal spores are main cause of infection and threat to immunocompromised individuals by contaminating products and surgical instruments and producing mycotoxins in different food products. Now a day‘s people spent more time in indoor environment than outdoor environment. In indoor there is less air and maintenance is improper. As more time is spent indoor so the problem of headache, feeling of tiredness and pressure on head occur. Fungi are present everywhere in nature and cause serious problem to public health in indoor environment. From indoor environment many fungi are isolated. On natural and synthetic material fungus are able to grow especially when the humidity is present in environment. Inorganic material actS as good substrate for the growth of aspergillus. Fungus attacks on wood. On painted surfaces aspergillus mostly grows. Due to exposure to mycotoxin contaminated food the hypersensitivity pneumonitis occurs. Immunocompromised individual‘s spent more time indoor and exposure to aspergillus species result in serious respiratory disorders such as allergic Broncho pulmonary aspergillosis, semi invasive pulmonary aspergillosis and pulmonary aspergilloma. Disinfectants are chemical which reduce the number of microorganism which can cause infection to human health. Disinfectant should have following properties. Disinfectant should have broad spectrum of activity, in presence of organic matter the disinfectant act, disinfectant should have high penetrating power and act in both acidic and alkaline pH. Disinfectant should be nontoxic and cost effective. Disinfectant should be nonirritant for skin and store for long time. Different disinfectants are used to control fungal infections. Mostly alcohol, quaternary ammonium compound, biguanides, phenols, aldehyde are used. The proper and effective use of disinfectant is necessary to restrain infection related to health care. There is need to investigate the efficacy of disinfectants against fungal spores. Isolates of Aspergillus parasiticus (n=20) was procured from project entitled as ―Purification and standardization of mycotoxins extracted from indigenous fungi under optimized experimental conditions‘‘. Aspergillus parasiticus was revived on Sabouraud‘s dextrose agar and identified on the base of macroscopic characters and microscopic characters. Macroscopic characters will be observed from obverse and reverse side of fungal growth on Sabouraud‘s dextrose agar. Microscopic features will be determined by cellophane tape method and slide culture method. Further DNA was extracted from fungal mycelia and then polymerase chain reaction (PCR) was performed. To confirm the result of PCR gel electrophoresis was performed. For this 2% agarose gel is made. After conformation through PCR Aspergillus parasiticus spore suspension 106 spores/mL (1 mL) was inoculated into Sabouraud‘s dextrose broth and incubated for 14-25 days at 25±3⁰C in dark for mycotoxin production. Then mycotoxin was extracted and mycotoxin was detected through thin layer chromatography (TLC). Thin layer chromatography plate was observed under UV light at 365nm. B1 and B2 toxin fluoresce blue while G1 and G2 fluorescece green under UV light. Toxigenic isolates of Aspergillus parasiticus was selected. Antifungal susceptibility of disinfectant was checked through well diffusion method. Disinfectants Terralin (quaternary ammonium compounds), Alpha guard (biguanides), Instru Star (amine), Hypochlorite (Halogens) and Isopropanol (alcohols) were checked through well diffusion method. Then check minimum inhibitory concentration by broth microdilution method of disinfectants Terralin (quaternary ammonium compounds), Alpha guard (biguanides), Instru Star (amine), Hypochlorite (Halogens). Then perform log reduction method for disinfectants and count CFU/mL at different incubation time.