Atrazine photochemical degradation in homogeneous phase using Fe(III)/UV/air system was studied. Two toxicity assessments, a Lemna minor growth inhibition test and a Daphnia magna acute immobilisation test, were employed to test potential toxicity of atrazine and its degradation products. The occurrence of atrazine in rivers from the Vltava River basin was evaluated from the analyses performed by Povodí Vltavy, State Enterprise.

Recently, the agricultural, industrial and mining activities have led to increase in contaminant emission. Trace metals or herbicides are among the pollutants to be concerned in the world. In this study we evaluated the effects of the herbicide atrazine (at the concentrations of 5, 50 and500 µg L-1) and its combination with copper (Cu, 50 µg L-1) and chromium (Cr, 50 µg L-1) on duckweed over the period of 10 days in the laboratory conditions. We found that 50 and 500 µg atrazine L-1 severely impacted on the growth or even caused the death of the plants, whereas there was no statistically significant difference in the duckweed growth rate between the 5 µg atrazine L-1 exposure and control. In the combined treatments (50 µg atrazine L-1 with Cu; with Cr or with both Cu and Cr), the plant growth rate of atrazine with either Cu or Cr was strongly reduced. However, the mixture of atrazine with Cu and Cr did not significantly decrease the development and growth rate of duckweed. Besides, atrazine and investigated heavy metals resulted in turning whiteof duckweek leaves that evidence ofthe chlorophyll degradation. Our results showed the negative influences of the herbicide atrazine and metals on development and morphology of duckweed. / Gần đây, những hoạt động nông nghiệp, công nghiệp và khai khoáng đã và đang dẫn đến sự gia tăng phát thải các chất gây ô nhiễm. Kim loại nặng hoặc thuốc diệt cỏ là những chất gây ô nhiễm đang được quan tâm trên thế giới. Trong nghiên cứu này, chúng tôi đánh giá ảnh hưởng của thuốc diệt cỏ atrazine (nồng độ 5, 50 và 500 µg/L) và sự kết hợp của chất này với đồng (Cu, 50 µg/L) và crom (Cr, 50 µg/L) lên bèo tấm trong thời gian 10 ngày trongđiều kiện phòng thí nghiệm. Chúng tôi nhận thấy atrazine tại nồng độ 50 và 500 µg/L đã gây nên những ảnh hưởng nghiêm trọng lên sự phát triển hay thậm chí làm cho bèo tấm bị chết, trong khi đó, không ghi nhận được bất kì sự khác biệt có ý nghĩa thống kê về tốc độ tăng trưởng của bèo tấm giữa lô thí nghiệm phơi nhiễm 5 µg atrazine / L và lô đối chứng. Trong những lô phơi nhiễm kết hợp (50 µg atrazine / L với Cu, với Cr hoặc với đồng thời Cu và Cr), tốc độ tăng trưởng của bèo tấm khi phơi nhiễm với atrazine và Cu hoặc Cr bị giảm mạnh, tuy nhiên, việc phơi nhiễm đồng thời atrazine với Cu và Cr đã không làm giảm đáng kể sự phát triển và tốc độ tăng trưởng của bèo tấm. Bên cạnh đó, atrazine và kim loại nặng đã làm cho màu của lá bèo tấm chuyển sang màu trắng, điều này chứng tỏ có sự suy giảm chlorophyll. Kết quả nghiên cứu này đã cho thấy những ảnh hưởng tiêu cựccủa thuốc diệt cỏ atrazine và kim loại lên sự phát triển và hình thái của bèo tấm.

O presente estudo teve como objetivos avaliar os efeitos ecotoxicológicos das ações individual e combinada dos fármacos cloridrato de propranolol e losartana potássica, por meio do ensaio de inibição do crescimento da macrófita aquática Lemna minor e comparar esses efeitos com os preditos por meio dos modelos de adição de concentração e ação independente. Buscou-se também calcular critérios de qualidade da água para a proteção da vida aquática para esses dois fármacos. Os testes de sensibilidade foram realizados empregando-se o cloreto de sódio como substância de referência. Os testes ecotoxicológicos foram conduzidos de acordo com Protocolo da OECD, com a modificação do uso de fotoperíodo ao invés de luz contínua para simular condições ambientais mais realísticas. As bases de dados Ecotox Database e da National Centers for Coastal Ocean Science foram consultadas, respectivamente, para a obtenção de dados ecotoxicológicos para a derivação dos critérios de qualidade da água e para a obtenção de dados previstos por meio de relações quantitativas estrutura-atividade (RQEA). Com relação aos testes de sensibilidade, todos os resultados estiveram dentro da faixa de aceitabilidade ao nível de confiança de 95%, com um valor médio de concentração efetiva mediana (CE50) de 4042,6 mg.L-1. Os testes com o fármaco cloridrato de propranolol para os parâmetros número de frondes, área foliar total e peso fresco resultaram nos valores médios de CE50 respectivos de 101,4 mg.L-1; 76,2 mg.L-1 e 84,0 mg.L-1, enquanto que nos testes com a losartana potássica esses valores foram, respectivamente, de 63,9 mg.L-1; 61,3 mg.L-1 e de 76,9 mg.L-1. Os valores de CENO e de CEO obtidos nos testes com o cloridrato de propranolol foram de 1,56 mg.L-1 e 3,1 mg.L-1, respectivamente, enquanto que nos testes com a losartana potássica, esses valores foram de 0,78 mg.L-1 e de 1,56 mg.L-1. O teste de ação combinada com os fármacos mostrou que ambos os modelos preditivos superestimaram, em todos os níveis de concentração testados, os efeitos de toxicidade da mistura nos testes com a L. minor. Portanto, observaram-se interações antagonísticas na ação combinada desses dois fármacos em relação aos efeitos preditos pelos modelos de referência. Com relação aos critérios de qualidade da água, calcularam-se os valores de 0,9 e 0,18 µg.L-1 de cloridrato de propranolol para a proteção das espécies pelágicas de água doce e salina, respectivamente, enquanto que para a losartana potássica, os valores preliminares calculados para a proteção das espécies de água doce e marinhas foram, respectivamente, de 0,055 e de 0,0055 µg.L-1. Os resultados obtidos permitiram observar que a losartana potássica mostrou-se mais tóxica para L. minor do que o cloridrato de propranolol. Além disso, a macrófita mostrou-se mais sensível aos efeitos de toxicidade da losartana potássica do que outras espécies relatadas na literatura. O teste de mistura mostrou que a capacidade dos dois modelos avaliados em predizer a toxicidade de misturas é limitada. As concentrações do cloridrato de propranolol em ambientes aquáticos não ultrapassam os critérios de qualidade da água. Testes crônicos adicionais com a losartana são necessários para a derivação de critérios definitivos. / This study aimed to evaluate the single and joint ecotoxicological effects of the drugs propranolol hydrochloride and losartan potassium, using the Lemna minor growth inhibition test and to compare the observed effects with those predicted by the models of concentration addition and independent action. In addition, water quality criteria were derivated for the protection of aquatic life against the possible adverse effects caused by these antihypertensive drugs. The sensitivity tests were carried out employing sodium chloride as a reference substance. Ecotoxicological tests were carried out according to OECD protocol, with the modification of using photoperiod instead of continuous lighting, in order to provide conditions closer to the environmental ones. The Ecotox Database and the database of the National Centers for Coastal Ocean Science were consulted for derivation of the water quality criteria and for the data predicted by quantitative structure-activity relationships (QSARs), respectively. With regard to the sensitivity tests, all results were within the range of acceptability at a 95% confidence level, with a mean value of median effective concentration (EC50) of 4042.6 mg.L-1. The tests with propranolol hydrochloride for the parameters frond number, total frond area and fresh weight resulted in mean EC50 values of 101.4 mg.L-1; 76.2 mg.L-1 and 84.0 mg.L-1, respectively, whereas in the tests with losartan potassium, those EC50 values were 63.9 mg.L-1, 61.3 mg.L-1 and 76.9 mg.L-1, respectively. The NOEC and LOEC values obtained in the tests with propranolol hydrochloride were 1.56 mg.L-1 and 3.1 mg.L-1, respectively, whereas in the tests with losartan potassium, these values were 0.78 mg.L-1 and 1.56 mg.L-1, respectively. Both the reference predictive models overestimated the mixture toxicity of the pharmaceuticals at all the effect concentration levels evaluated in the L. minor test. Therefore, the mixture of propranolol hydrochloride and losartan potassium showed an antagonistic interaction in the L. minor test in comparison to the predicted effects. Regarding to the water quality criteria, the values of 0.9 and 0.18 µg.L-1 of propranolol hydrochloride were calculated for the protection of pelagic organisms living in freshwater and marine ecosystems, respectively, whereas for losartan potassium, the calculated preliminary criteria for protection of pelagic organisms living in freshwater and saltwater ecosystems were 0.055 and 0.0055 µg.L-1, respectively. The results showed that losartan potassium proved to be more toxic to L. minor than propranolol hydrochloride. Furthermore, this macrophyte seemed to be more sensitive to losartan toxicity than other organisms reported in the literature. The mixture test showed that the capability of the two reference models in accurately predicting the mixture toxicity is limited. The concentrations reported of propranolol hydrochloride in aquatic environment are not usually higher than the water quality criteria values. More data on chronic test to losartan are necessary in order to derive definitive criteria.

Transgenic plant systems have been proposed as bioreactors in the production of pharmaceutical and industrial proteins. The economic benefits of inexpensive plant production systems could be erased if the downstream processing ends up being expensive. To avoid monoclonal antibody (mAb) modification or fouling of chromatography resins, removal of phenolics from plant extracts is desirable. Removal of major phenolics in Lemna extracts was evaluated by adsorption to PVPP, XAD-4, IRA-402 and Q-Sepharose resins. Analysis of phenolics adsorption to XAD-4, IRA-402 and Q-Sepharose showed superior dynamic binding capacities at pH 4.5 than at 7.5. The economic analysis using SuperPro Designer 7.0 indicated that addition of a phenolics adsorption step would increase mAb production cost only 20% by using IRA-402 compared to 35% for XAD-4 resin. The overall mAb processing cost can be reduced by implementing a phenolics removal step. To understand phenolics-resin interactions, adsorption isotherms of phenolic compounds (chlorogenic acid, ferulic acid, rutin, syringic acid and vitexin-2-O-rhamnoside) from different phenolic classes on three resins (IRA-402, PVPP, XAD-4) at pH 4.5 and 7.5 were determined. Differences in adsorption with the type of phenolics were observed, and PVPP was not efficient for phenolics removal. Screening of sugarcane lines for bovine lysozyme (BvLz) accumulation indicated that expression levels are still inadequate for commercial development. To maximize BvLz extraction, pH and ionic strength were evaluated; five conditions resulted in equivalent BvLz/TSP ratio. Membrane filtration process using BvLz extracts attained partial removal of native proteins by the 100 kDa membrane step, but also BvLz loss (21-29%). Regardless of the extraction condition, at least 47% of the starting BvLz was lost during the membrane processing. None of the evaluated extraction conditions caused a substantial recovery of BvLz in the concentrate. Alternative purification options for the IEX+HIC process, which achieved 95% BvLz purity, were tested. Direct loading of sugarcane extract concentrate on HIC and XAD-4 pretreatment of juice did not recovered BvLz as effectively as the IEX chromatography. Pure BvLz was obtained by the XAD+HIC process, but higher purification fold and HIC yield were achieved by the IEX+HIC process, due to the complete separation of BvLz and 18-kDa protein.

京都大学 / 新制・課程博士 / 博士(理学) / 甲第24078号 / 理博第4845号 / 新制||理||1693(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)准教授 小山 時隆, 教授 田村 実, 教授 山内 淳 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM