• Journal of Plant Biology
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• 제3권2호
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• pp.6-18
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• 1960

The present experiments were designed in order to clarify the differences between the long and short styled plants and the transgressive gradition in the degree of dimorphism among the three heterostylous species of the Polygonus, P. japonica, F. esculentum, and P. senticosa, based on investigations regarding the floral structure, ecological and physiological traits, the results of which are summarized as follows: (1) P. japonica, although it exhibits typical dimorphism, has undergone so high a differentiation between long and short styled that its long styled individuals behave as if they were female; and short styled individuals as if male. In long-styled individuals, filament, anther, and pollen grains show signs of degeneration, most of the pollen being abortive. On the other hand, in short styled individuals, the filament, anther, and pollen grains have attained remarkable development; the pollen grians are large and fertile. In short-plant the fertilized flowers readily drop off in every stage of their embryo development. This species has completely lost the self-fertile property, which is characteristic of the non-dimorphic Polygonum genus. Although this specsei typically exhibits the physiological characteristics of the non-dimorphic Polygonum genus. Although this specisei typically exhibits the physiological characteristics of dimorphism in controlled pollination, the short-styled individuals bear no seed in nature, thus misleading taxonomists to idenfity the short-styled plant as male. 2) The morphological feature of the flower organ of P. senticosa obviously indicates definite dimorphism. Physiologically, however, no differentiation towards dimorphism was observed, the species still retaining, both in long and short-individuals, the self-fertile property common to the Polygonum genus. Elaborate examinations revealed that regardless of the modes of pollination, both fertiization and seed setting flourish, no differentiation betwen legitimate and illegitimate unions being recognizable. This sort of physiological property has not been observed in the investigations of other heterostylous plants. It is assumed that this species is differentiated structurally into dimorphism, but not yet physiologically. In nature, however, this plant would have more opportunities to be cross-pollinated, i.e., legitimately combined, than self-pollinated because of the development of two forms of flowers. 3) In terms of heterostylism, the F. esculentum just occupies the intermediate position between P. japonica and P. senticosa structurally, ecologically, and physiologically. Doescription of some of the physiological behavior of the plant will suffice to demonstrate the above facts. While P. japonica has completely lost its self-fertile property, P. senticosa still retains it wolly. In F. esculentum 2-6% of self-fertility is the result in illegitimate combination. There occur occasionally hereditary self fertile individuals among some of the F. or 20 min. irradiation plot, when they reach any stage of the same bacterial population. In addition to this increase of total population in the plots with the more dose of UV light irradiation, it seems that the more dose of UV light irradiation is the more shortened the generation time of Azotobacter. Therefore, it is clear that variation of reproductive rate must be, mere or less, due to the genetic effects induced by UV light irradiation. On the other hand, the lag phase or logarithmic growth phase in nonirradiated culture is shortened prominently, and this must be due to the difference in bacterial number of the original inoculm. The generation time of Azotobacter is shortened by exogeneous treatment of nuclei acid derivatives, and the degree is greater in case of DNA derivatives than RNA dervatives. W.H. Price reported that the rate of ribose nucleic acid to protein in Staphylococcus muscae is proportional to the generation time: that is the faster the cell can form ribose nucleic acid, the more rapid its growth. This explains the shortening of generation time by exogeneous RNA derivatives in this work reasonably. On the other hand, it is well known that the desoxyribose nuclic acid content per cell is constant and independent of the generation time. A.D. Laren and W.N. Takahashi reported that the infectious RNA from TMV is 6 times as sensitive to inactivation by UV as it is in the form of intact virus, and that inactivation of infectious TMV involves onlu a local change on RNA chain. But, the effect of exogeneous DNA in this work suggests that irradiated living cell which cotain DNA bring about some change on DNA moleculs as well as RNA molecules. And if the mutagenic effects of UV take into consideration, it is very reasonable. Therefore, it is clear that the variation of the generation time by UV irradiation is, more or less, due to the genetic effects. Therefore, it seems that the shortness of the average lifewpan of Azotobacter by UV irradiation is resulted not only from the influence of the environmental conditions, but also from the variation of genetic factor of the individual.

• 한국식품위생안전성학회지
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• 제26권4호
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• pp.349-354
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• 2011

시중에서 판매된 일반우유와 포름알데히드를 처리한 참치어유 배합사료를 먹여 DHA를 강화한 DHA 강화우유내의 포름알데히드 함량을 분석함으로써 포름알데히드를 처리한 사료를 먹여 DHA를 강화한 우유의 안전성을 평가하고자 하였다. 시중에서 판매된 일반우유와 DHA 강화우유를 CM, DHA-K, DHA-B로 구분하였다. 이화학 검사를 통해 세 제품이 모두 기준치 이내의 정상 수준을 나타내는 신선한 제품임을 확인하였고, 전반적인 시료간의 유의적 차이는 거의 없었으나, DHA-K를 다른 두 시료와 비교하면 지방함량은 두 시료의 지방함량의 절반 정도인 1.85%이었으며, 단백질은 약 1% 높게 나타났다. DHA 강화우유에 함유된 DHA의 함량을 분석해본 결과 DHA-B가 DHA-K보다 약 2배이상 높게 나타났으며, 이러한 차이는 연령별 섭취량 기준과 비슷한 양상을 나타내는 것으로 보인다. HPLC를 이용하여 우유 내 포름알데히드를 분석한 결과, 일반우유와 포름알데히드를 처리한 참치어유배합사료를 먹인 DHA 강화우유 모두 WHO에서 정한 신선유 중 포름알데히드 함량 기준치인 0.013~0.057 ppm사이에 존재했으며, 또한 세 시료간에 유의적 차이가 없는 것으로 보아 DHA를 강화하기 위해 포름알데히드를 첨가한 참치어유 배합사료를 소에게 먹이더라도 포름알데히드가 우유로 전이되지는 않는 것으로 보이며, 포름알데히드를 처리한 사료를 먹인 DHA 강화우유의 포름알데히드에 대한 안전성은 일반우유 수준이라고 판단된다.