Ultraviolet inactivation

The ultraviolet inactivation spectrum for gramicidin has been published by Setlow and Doyle121. Sugimoto and coworkers have presented infrared, ultraviolet, visible and ESR spectra for gramicidin solutions irradiated with various amounts of ultraviolet light122. 

R. B. Setlow, Molecular Changes Responsible for Ultraviolet Inactivation of the Biological Activity of DNA, in Mammalian Cytogenetics and Related Problems in Radiobiology, Pergamon Press, Long Island City, NY, 1964. 

Magbanua BS, Jr, Savant G, Truax DD. Combined ozone and ultraviolet inactivation of Escherichia coli. J Environ Sci Health Part A Tox Hazard Subst Environ Eng 2006 41 (6) 1043 55. 

Gaugler, R., Bednarek, A. and Campbell, J.F. (1992) Ultraviolet inactivation of heterorhabditid and steinemematid nematodes. Journal of Invertebrate Pathology 59, 155-160. 

Jagger J Ultraviolet inactivation of biological systems. In Photochemistry and Photobiology of Nucleic Acids Biology. Volume II. Edited by Wang SY. New York Academic Press 1976 147—186. 

A. Norman, A nuclear role in the ultraviolet inactivation of Neurospora conidia, J. Cell. 

Yaoi, Y., and Amano, M., 1970, Inhibitory effect of ultraviolet inactivated vesicular stomatitis virus on inhibition of DNA synthesis in cultured chick embryo cells, J. Gen. Virol. 9 69. 

Rupert, C.S., Goodgal, S., and Herriot, R.M., Photoreactivation of ultraviolet inactivated Hemo-phila influenzae transforming factor, /. Gen. Physiol, 41,451,1958. 

Heat is the most reliable method of virus disinfection. Most human pathogenic viruses are inactivated following exposure at 60°C for 30 minutes. The virus of serum hepatitis can, however, survive this temperature for up to 4 hours. Viruses are stable at low temperatures and are routinely stored at -40 to -70°C. Some viruses are rapidly inactivated by drying, others survive well in a desiccated state. Ultraviolet light inactivates viruses by damaging their nucleic acid and has been used to prepare viral vaccines. These facts must be taken into account in the storage and preparation of viral vaccines (Chapter 15). 

Ryu, H., Gerrity, D., Crittenden, J.C. andAbbaszadegan, M. (2008) Photocatalytic inactivation of Cryptosporidium parvum with Ti02 and low-pressure ultraviolet irradiation. 

Figure 9.4 Repair of DNA inactivated by ultraviolet light. Light causes die dimerization of adjacent thymine residues that block DNA replication. The four enzymes shown are involved in removal and replacement of a portion of the DNA that contains the dimer.

Mycobacterium tuberculosis, ultraviolet germicidal irradiation in inactivating airborne microorganizms, 5 654 Mycoherbicides, 23 332 Mycoplasma, in fermentation, 11 AG Mycostats, in pet foods, 10 855 Myers and Montgomery experimental design text versus other texts,... 

Hadjok, C., Mittal, G. S., and Warriner, K. (2008). Inactivation of human pathogens and spoilage bacteria on the surface and internalized within fresh produce by using a combination of ultraviolet light and hydrogen peroxide. J. Appl. Microbiol. 104,1014-1024. 

Hemotoxic activity. Seed oil, administered orally to human adults, produced thrombocytosis in children, the effect was inactivated by ultraviolet radiation . Hypercholesterolemic activity. Seed oil, administered by gastric intubation to rabbits at a dose of 0.4 g/kg, was inactive " . Male Wistar rats fed 12 or 24% sesame oil in the diet for 4 weeks were investigated. The rats on the 24% sesame oil diet had significantly lower lymphatic cholesterol and fatty acids . 

Munakata, N. Hieda, K. Kobayashi, K. Ito, A. Ito, T. Action spectra in ultraviolet wavelengths (150-250 nm) for inactivation and mutagenesis of Bacillus subtilis spores obtained with synchrotron radiation. Photochem. Photobiol. 1986, 44 (3), 385-390. 

Munakata, N. Saito, M. Hieda, K. Inactivation action spectra of Bacillus subtilis spores in extended ultraviolet wavelengths (50-300 nm) obtained with synchrotron radiation. Photo-chem. Photobiol. 1991, 54 (5), 761-768. 

The presence of proflavine protects some viruses against inactivation by ultraviolet radiation and proflavine has been shown to inhibit formation of thymine dimers in DNA.86 (6) The sensitivity of microorganisms to ultraviolet light increases with, but is not proportional to the square of, the thymine content of the DNA.86 (7) Substitution of... 

The correlation between definite photoproducts and biological action of ultraviolet light discussed in this section is confined to a particular action of ultraviolet light, namely an inactivating or lethal action. Microorganisms are killed, DNA synthesis in cells is inhibited, transforming DNA is inactivated, template activity of DNA is reduced, and phage and viruses are inactivated because the pyrimidine dimer which is formed in-strand is apparently able to provide a block which hinders DNA or RNA replication. 

Another approach is the whole-killed or inactivated vaccine. These vaccines are derived from the pathogen itself, rather than a weakened form, as are live attenuated vaccines. Chemical (e.g., formalin, ether, and beta-propiolactone) or physical (e.g., heat, ultraviolet, and gamma irradiation) means, or combinations thereof, are used to inactivate the pathogen. Notable examples of this type of viral vaccine include the inactivated polio vaccine... 

From an analytical perspective, the single most important physicochemical characteristic of riboflavin is its photosensitivity (80-82). Exposure of this vitamin to ultraviolet and visible light results in irreversible photoreduction to lumiflavin and lumichrome and loss of vitamin activity. In addition, the coenzymes are subject to hydrolysis by endogenous phosphatases that are present in a number of foods. Since these enzymes are generally inactivated by thermal processing, they are a concern only in the analysis of fresh products. 

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