• 한국식품과학회지
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• 제26권1호
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• pp.93-97
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• 1994

천연의 녹색 색소를 개발하기 위하여 Rhodopseudomonas viridis DSM 133이 생산하는 색소의 물리적, 화학적 특성을 조사하였다. 가시광선 범위에서의 흡수특성을 측정한 결과 이 색소는 흡수극대가 378, 414 및 677 nm인 3개의 main peak와 510, 540 및 618 nm인 3개의 minor peak를 확인할 수 있었으며 전반적으로 녹색색조를 나타내었다. 색소는 산성 영역 보다는 알카리 영역, 즉 pH $6.0{\sim}9.0$에서 보다 안정한 경향을 보였다. 그러나 광선과 산소 존재 하에서는 색소의 파괴가 촉진되었다. $40^{\circ}C$ 이하에서는 안정하였고, $Fe^{3+}$ 및 $Al^{3+}$에 의해서는 색조의 저하와 함께 혼탁이 발생되었으나 $Cu^{2+}$에 의해서는 안정성이 유지되었다. 본 색소는 TLC결과 4종의 색소로 구성되어 있었으며 주 색소는 F-4와 F-2로 나타났다.

• Environmental Engineering Research
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• 제12권4호
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• pp.136-147
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• 2007

In an effort to identify possible microbes for seeking bioagents for remediation of herbicide-contaminated soils, seven species of phototrophic nonsulfur bacteria (Rhodobacter capsulatus and sphaeroides, Rhodospirillum rubrum, Rhodopseudomonas acidophila, blastica and viridis, Rhodomicrobium vannielii) were grown in the presence of the herbicide, butachlor, and bacterial growth rates and nitrogen fixation were measured with different carbon sources. Under general conditions, all species showed 17-53% reductions in growth rate following butachlor treatment. Under nitrogen-fixing conditions, Rb. capsulatus and Rs. rubrum showed 1-4% increases in the growth rates and 2-10% increases in nitrogen-fixing abilities, while the other 5 species showed decreases of 17-47% and 17-85%, respectively. The finding that Rp. acidophila, Rp. blastica, Rp. viridis and Rm. vannielii showed stronger inhibitions of nitrogenase activity seems to indicate that species in genera Rhodobacter and Rhodospirillum are less influenced by butachlor than those in Rhodopseudomonas and Rhodomicrobium in terms of nitrogen-fixing ability. Overall, nitrogenase activity was closely correlated with both growth rate and glutamine synthetase activity (representing nitrogen metabolism). When the carbon sources were compared, pyruvate (three carbons) was best for all species in terms of growth rate and nitrogen fixation, with malate (four carbons) showing intermediate values and ribose(five carbons) showing the lowest; these trends did not change in response to butachlor treatment. We verified that each of the 7 species had a plasmid ($12.2{\sim}23.5\;Kb$). We found that all 7 species could use butachlor as a sole carbon source and 3 species were controlled by plasmid-born genes, but it is doubtful whether plasmid-born genes were responsible to nitrogen fixation.