Russian researchers discovered that light, which got through a light-adjusting film, has stimulated biochemical activity of oil-degrading bacteria of genus Pseudomonas: Pseudomonas stutzeri and Pseudomonas putida. The work has been done in the Institute of Oil Chemistry, Siberian branch of Russian academy of sciences.

All plants and many microorganisms have special photo-regulating systems, which are effective tools for regulation of growth and development of these organisms. During the process of photosynthesis, for instance, a plant absorbs photons with longer wavelengths (from red spectral range), that is why scientists suggest using special light-adjusting films, which absorb solar ultraviolet radiation and transform it into red light and therefore contribute to crop yield improvement. Researchers from the Institute of Oil Chemistry suggest using similar light-adjusting films for growing microorganisms, like soil microbial population, which actively participates in biological degradation of oil and petroleum products.

 

 

Pollution of our environment is a serious problem, especially if we want to leave our planet suitable for further living of our descendants and other living organisms. Researchers from Tomsk have thoroughly studied the effect light-adjusting films have on microorganisms of genus Pseudomonas because these bacteria are widely spread in nature and actively participate in processes of degradation of various organic compounds.

Bacterial strains, used in this research, were Pseudomonas stutzeri and Pseudomonas putida, isolated from stratal waters of oil reservoir. Microorganisms were grown under various conditions: under light with a light-adjusting film, which transforms radiation into red light with wavelength of 615 nanometers; under light with a high pressure polyethylene film, which is transparent for all kinds of solar radiation; under a glass cover, which is opaque for ultraviolet radiation; and without any light. Glass cover and darkness experiments served as controls. All strains were irradiated for 6 hours every day for 15 days. The lamps were emitting visible light (400-710 nanometers) and ultraviolet radiation.

The experiment demonstrated that under a light-adjusting film the number of microorganisms was 100-500 times higher, than in the control variants of the study. Moreover, metabolic processes in bacterial cells appeared to go on much faster. Enzymes of oxidative metabolism in bacteria under the film also became more active, thus leading to much faster degradation of oil and petroleum products. This phenomenon can be applied in nature for effectively eliminating oil spills, for instance, before they do any significant damage to the environment.

The mechanism of stimulating effect of the red light still remains unclear, however, researchers offer several hypotheses, which can explain this phenomenon. Elimination of DNA-damaging ultraviolet radiation should definitely be one of these hypotheses.