Biodegradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1

Pyrethroid pesticide cypermethrin is a environmental pollutant because of its widespread use, toxicity and persistence. Biodegradation of such chemicals by microorganisms may provide an cost-effective method for their detoxification. We have investigated the degradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1 in various matrices such as, polyurethane foam (PUF), polyacrylamide, sodium alginate and agar. The optimum temperature and pH for the degradation of cypermethrin by immobilized cells of Micrococcus sp. were found to be 30 °C and 7.0, respectively. The rate of degradation of 10 and 20 mM of cypermethrin by freely suspended cells were compared with that of immobilized cells in batches and semi-continuous with shaken cultures. PUF-immobilized cells showed higher degradation of cypermethrin (10 mM and 20 mM) than freely suspended cells and cells immobilized in other matrices. The PUF-immobilized cells of Micrococcus sp. strain CPN 1 were retain their degradation capacity. Thus, they can be reused for more than 32 cycles, without losing their degradation capacity. Hence, the PUF-immobilized cells of Micrococcus sp. could potentially be used in the bioremediation of cypermethrin contaminated water.

Micrococcal botryomycosis of the left temporal region.

Botryomycosis arises from chronic infections produced by low-virulence organisms in an altered host environment. Staphylococci have been the most common organisms implicated, but various other bacteria have also been identified in human botryomycosis lesions. The relative balance between the host's resistance and the microorganism's virulence may be altered in some way that perpetuates the growth of the lesions in a symbiotic fashion. The diagnosis of botryomycosis is one that is often easily overlooked because it can be confused with other mycetomas such as actinomycosis and nocardosis. We report here a case of micrococcal botryomycosis that occurred in the left temporal region in a 70 year-old male, which was diagnosed by the help of a histopathological examination and microbial cultures.