Articles de revues : « PAM fluorimetria »

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Shimkevich, Andrey M., V. N. Makarov, Inessa M. Goloenko et Oleg G. Davydenko. « Functional State Of Photosynthetic System In Barley Alloplasmic Lines ». Ecological genetics 4, n^o 2 (15 juin 2006) : 37–42. http://dx.doi.org/10.17816/ecogen4237-42.

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The peculiarities of photosynthetic system functioning in barley alloplasmic lines were investigated by PAM fluorimetry. The substitution of nuclear genome was shown to affect differently several photosynthetic parameters. The importance of the balance between nuclear and organelle barley genetic systems for the photosystem II functioning was demonstrated.

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Turner, NC, LJ Wood, M. Foster et T. Gueremy. « Effects of PAF, FMLP and opsonized zymosan on the release of ECP, elastase and superoxide from human granulocytes ». European Respiratory Journal 7, n^o 5 (1 mai 1994) : 934–40. http://dx.doi.org/10.1183/09031936.94.07050934.

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Platelet-activating factor (PAF) is a potent chemoattractant for human eosinophils and neutrophils and causes eosinophil and neutrophil recruitment into animal airways. Since eosinophils and eosinophil cationic proteins are thought to play an important role in the pathophysiology of asthma, we have examined the hypothesis that PAF may also stimulate eosinophil cationic protein (ECP) release from human granulocytes. Granulocytes (93% neutrophils, 3% eosinophils) were isolated from the blood of normal volunteers, using metrizamide density gradients, and stimulated in vitro with PAF, L-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) or opsonized zymosan (OPZ). Superoxide generation was measured colorimetrically, granulocyte degranulation by a fluorimetric assay for elastase, and eosinophil activation by specific radioimmunoassay (RIA) for ECP. Granulocyte chemotaxis was also measured. Whilst both PAF and FMLP were potent chemoattractants for human mixed granulocytes (concentrations producing half the maximal effect (EC50s) ca 10 nM), PAF at concentrations below 10 microM was a poor stimulus to superoxide generation, elastase release or ECP release from the same cell population. In contrast, FMLP was a potent stimulus to both superoxide generation (EC50 48 nM) and ECP (EC50 ca 100 nM) and elastase release (EC50 ca 1 microM). OPZ was a potent stimulus to superoxide generation, but was a poor stimulus to ECP or elastase release. Thus, although PAF is a potent chemoattractant for human granulocytes, our results suggest that it alone may not stimulate their subsequent activation and release of cytotoxic products.

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Guarini, J. M., et C. Moritz. « Modelling the dynamics of the electron transport rate measured by PAM fluorimetry during Rapid Light Curve experiments ». Photosynthetica 47, n^o 2 (1 juin 2009) : 206–14. http://dx.doi.org/10.1007/s11099-009-0034-3.

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Engelsma, J. W., et J. Simons. « Simple fluorimetric screening for carazolol in swine kidneys bij means of Sep‐Pak cartridges ». Veterinary Quarterly 7, n^o 1 (janvier 1985) : 73–76. http://dx.doi.org/10.1080/01652176.1985.9693957.

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Saengsrichan, Aphinan, Chaiwat Saikate, Peeranut Silasana, Pongtanawat Khemthong, Wanwitoo Wanmolee, Jakkapop Phanthasri, Saran Youngjan et al. « The Role of N and S Doping on Photoluminescent Characteristics of Carbon Dots from Palm Bunches for Fluorimetric Sensing of Fe3+ Ion ». International Journal of Molecular Sciences 23, n^o 9 (30 avril 2022) : 5001. http://dx.doi.org/10.3390/ijms23095001.

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This work aims to enhance the value of palm empty fruit bunches (EFBs), an abundant residue from the palm oil industry, as a precursor for the synthesis of luminescent carbon dots (CDs). The mechanism of fIuorimetric sensing using carbon dots for either enhancing or quenching photoluminescence properties when binding with analytes is useful for the detection of ultra-low amounts of analytes. This study revealed that EFB-derived CDs via hydrothermal synthesis exceptionally exhibited luminescence properties. In addition, surface modification for specific binding to a target molecule substantially augmented their PL characteristics. Among the different nitrogen and sulfur (N and S) doping agents used, including urea (U), sulfate (S), p-phenylenediamine (P), and sodium thiosulfate (TS), the results showed that PTS-CDs from the co-doping of p-phenylenediamine and sodium thiosulfate exhibited the highest PL properties. From this study on the fluorimetric sensing of several metal ions, PTS-CDs could effectively detect Fe3+ with the highest selectivity by fluorescence quenching to 79.1% at a limit of detection (LOD) of 0.1 µmol L−1. The PL quenching of PTS-CDs was linearly correlated with the wide range of Fe3+ concentration, ranging from 5 to 400 µmol L−1 (R2 = 0.9933).

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Koenig, Samuel, Candida Savage et Jonathan P. Kim. « Non-destructive assessment of polycyclic aromatic hydrocarbon (PAH) exposure by fluorimetric analysis of crab urine ». Marine Pollution Bulletin 56, n^o 12 (décembre 2008) : 2003–8. http://dx.doi.org/10.1016/j.marpolbul.2008.08.010.

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Conde-Giménez, María, et Javier Sancho. « Unravelling the Complex Denaturant and Thermal-Induced Unfolding Equilibria of Human Phenylalanine Hydroxylase ». International Journal of Molecular Sciences 22, n^o 12 (18 juin 2021) : 6539. http://dx.doi.org/10.3390/ijms22126539.

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Human phenylalanine hydroxylase (PAH) is a metabolic enzyme involved in the catabolism of L-Phe in liver. Loss of conformational stability and decreased enzymatic activity in PAH variants result in the autosomal recessive disorder phenylketonuria (PKU), characterized by developmental and psychological problems if not treated early. One current therapeutic approach to treat PKU is based on pharmacological chaperones (PCs), small molecules that can displace the folding equilibrium of unstable PAH variants toward the native state, thereby rescuing the physiological function of the enzyme. Understanding the PAH folding equilibrium is essential to develop new PCs for different forms of the disease. We investigate here the urea and the thermal-induced denaturation of full-length PAH and of a truncated form lacking the regulatory and the tetramerization domains. For either protein construction, two distinct transitions are seen in chemical denaturation followed by fluorescence emission, indicating the accumulation of equilibrium unfolding intermediates where the catalytic domains are partly unfolded and dissociated from each other. According to analytical centrifugation, the chemical denaturation intermediates of either construction are not well-defined species but highly polydisperse ensembles of protein aggregates. On the other hand, each protein construction similarly shows two transitions in thermal denaturation measured by fluorescence or differential scanning calorimetry, also indicating the accumulation of equilibrium unfolding intermediates. The similar temperatures of mid denaturation of the two constructions, together with their apparent lack of response to protein concentration, indicate the catalytic domains are unfolded in the full-length PAH thermal intermediate, where they remain associated. That the catalytic domain unfolds in the first thermal transition is relevant for the choice of PCs identified in high throughput screening of chemical libraries using differential scanning fluorimetry.

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Hovaneissian, Michael, Paul Archier, Carole Mathe, Gérald Culioli et Catherine Vieillescazes. « Analytical investigation of styrax and benzoin balsams by HPLC- PAD-fluorimetry and GC-MS ». Phytochemical Analysis 19, n^o 4 (9 novembre 2007) : 301–10. http://dx.doi.org/10.1002/pca.1048.

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Humphries, Julia, Kevin Burnand, Philip Cunningham, Adrian Brock, Nigel Westwood et Alberto Smith. « Identification of Potentially Effective Antisense Oligodeoxyribonucleotide (ODN) Sequences for Inhibiting Plasminogen Activator Inhibitor-2 (PAI-2) Production by Monocytes ». Thrombosis and Haemostasis 88, n^o 07 (2002) : 131–36. http://dx.doi.org/10.1055/s-0037-1613165.

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SummaryMonocyte fibrinolytic activity may influence thrombus resolution. The balance between uPA and PAI-2 could determine the fibrinolytic activity of the monocyte. Inhibiting PAI-2 production using specific antisense sequences might alter this balance. Selecting effective sequences is a problem as prediction of the secondary structure of target mRNA is difficult. This study reports the modification of a cell free system for rapid antisense screening.Five 18-19 mer oligodeoxynucleotides (ODN), sequences A, B, K, T and Q, and their matched scrambled controls were designed and screened using a modified rabbit reticulocyte lysate transcription and translation system (RRL). Intracellular uptake of ODNs was confirmed by fluorescence microscopy, scanning laser confocal microscopy and fluorimetery. Monocytes were transfected with a liposome/ODN complex using sequences A, B, A + B combined, or T and PAI-2 levels measured by ELISA. Inhibition of PAI-2 production was calculated as a percentage of control levels (baseline and scrambled). (i) RRL System – Sequence A was the most effective inhibitor of PAI-2 production in this system (median 63%) compared with sequences, B median 9%, K median 14%, T median 11% and Q median –8% respectively (n = 3). Sequence A was the only sequence, which always inhibited PAI-2. This was confirmed using fluorescently labelled protein (n = 2). (ii) Monocyte transfection Fluorescence microscopy and fluorimetry showed that intracellular delivery of labelled antisense was only achieved when a liposome was used. Transfection of monocytes extracted from 5 subjects showed that sequence A significantly reduced PAI-2 production (mean % 41.4, sem 9.1) compared with sequences B (mean% 3.4, sem 8.9, p = 0.04), A + B (mean % 0.4, sem 7.8, p = 0.04), and T (mean % 5.4, sem 4.9, p = 0.01). Futher studies using sequence A on cells from 10 subjects showed a significant reduction in monocyte PAI-2 production (27.6 ng/ml, sem 3.9) compared with matched scrambled controls (mean 38.3 ng/ml, sem 4.5, p = 0.0112) and baseline (mean 51.4 ng/ml, sem 6.7, p = 0.0009).Use of the RRL screening system allowed the selection of a novel antisense sequence, which significantly reduced PAI-2 production in monocytes.

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Donafologo Baba, SORO, NGUETTIA Kossonou Roland, DIARRA Moussa, MEITE Ladji, ABOUA Kouassi Narcisse, KOUASSI Kouakou Edouard, KONE Mamadou et TRAORE Karim Sory. « NIVEAU DE CONTAMINATION DE LA CHAIR DE POULET BICYCLETTE (GALLUS GALLUS DOMESTICUS) PAR LES HYDROCARBURES AROMATIQUES POLYCYCLIQUES (HAP) ». International Journal of Advanced Research 10, n^o 10 (31 octobre 2022) : 802–7. http://dx.doi.org/10.21474/ijar01/15548.

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Polycyclic aromatic hydrocarbons (PAHs) are among the organic pollutants sought both in the various environmental compartments (water, soil, air, etc.) and in food intended for human consumption. They are a group of persistent organic pollutants that are potentially mutagenic and carcinogenic. Thus, the present study aims to determine the PAH levels in the flesh of local poultry also called bicycle chickens (gallus gallusdomesticus). Ten (10) composite samples of chickens were collected in Karakoro, a locality located in the department of Korhogo in the north of Cote dIvoire. After the extraction and purification steps, the samples were analyzed on a Shimadzu brand HighPerformance Liquid Chromatograph (HPLC) equipped with a fluorimetric detector. The measured PAHs, eight (8) molecules in number, are classified among the priority substances to be researched in the context of food safety (fluoranthene, pyrene, benzo(k)fluoranthene, benzo(a)pyrene, indeno(1 ,2,3-cd) pyrene, benzo (g,h,i) perylene, benzo (a) anthracene, benzo (b) fluoranthene). The results obtained showed the presence of these molecules in the samples analyzed at concentrations higher than the European Union (EU) standard for some. On the other hand, all the PAHs determined have concentrations lower than the Codex Alimentarius standard.

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Watson, Giles M., Odd-Ketil Andersen, Tamara S. Galloway et Michael H. Depledge. « Rapid assessment of polycyclic aromatic hydrocarbon (PAH) exposure in decapod crustaceans by fluorimetric analysis of urine and haemolymph ». Aquatic Toxicology 67, n^o 2 (avril 2004) : 127–42. http://dx.doi.org/10.1016/j.aquatox.2003.11.006.

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Nieva-Cano, M. J., S. Rubio-Barroso et M. J. Santos-Delgado. « Determination of PAH in food samples by HPLC with fluorimetric detection following sonication extraction without sample clean-up ». Analyst 126, n^o 8 (2001) : 1326–31. http://dx.doi.org/10.1039/b102546p.

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Zhurba, Olga M., Anton N. Alekseenko, Salim F. Shayakhmetov et Alexey V. Merinov. « Assessment of the content of pollutants in accumulating natural environments under conditions of anthropogenic load ». Hygiene and sanitation 99, n^o 10 (30 novembre 2020) : 1049–54. http://dx.doi.org/10.47470/0016-9900-2020-99-10-1049-1054.

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Introduction. For a comprehensive study of the urban environment, various natural objects, there were used - snow and soil cover, accumulating atmospheric precipitation, which allows assessing the spread of pollutants in the environment. The purpose of the study is to assess the quantitative content of priority pollutants in the snow/soil system as a result of dispersion from man-made sources. Material and methods. Studies of the content of polycyclic aromatic hydrocarbons (PAHs), petroleum products (PP), and fluorides in snow and soils under man-made loads were carried out. Snow sampling was performed at sites with undisturbed snow cover during the beginning of snowmelt. Soil samples were taken at the same points where snow samples were previously taken. Gas chromatography-mass spectrometry, fluorimetric and potentiometric methods were used. Results. The detected PP content in samples of snow/soil samples was in the range of 0.04-0.98 mg/l/2.8-71.2 mg/kg; Σ PAH -2.13-134.76 mg/l/0.13-38.987 mg/kg; fluoride- in the range of 0.68-13.48 mg/l/1.5-61.0 mg/kg. High concentrations of pollutants were registered at points closest to man-made sources, as well as near highways and railway tracks. The composition of PAHs is relatively uniform at all sampling sites. snow samples were mainly dominated by low-molecular polyarenes - from 52.8 to 68.5% of ΣPAH, and soil samples - 5 -, 6-nuclear PAHs, the proportion of which varied from 63.7 to 85.3% of ΣPAH. Conclusion. Analysis of the obtained material shows the maximum concentrations of pollutants (PAH, PP, Fluorides) to be observed for snow and soil samples near the industrial zone: 0.35 km South of the aluminum plant, as well as in a soil sample taken from the village of Olkha, at a distance of 2.5 km from the source.

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de Velasco, Patricia C., Gustavo Chicaybam, Dionizio M. Ramos-Filho, Raísa M. A. R. dos Santos, Caroline Mairink, Fátima L. C. Sardinha, Tatiana El-Bacha, Antonio Galina et Maria das Graças Tavares-do-Carmo. « Maternal intake of trans-unsaturated or interesterified fatty acids during pregnancy and lactation modifies mitochondrial bioenergetics in the liver of adult offspring in mice ». British Journal of Nutrition 118, n^o 1 (14 juillet 2017) : 41–52. http://dx.doi.org/10.1017/s0007114517001817.

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AbstractThe quality of dietary lipids in the maternal diet can programme the offspring to diseases in later life. We investigated whether the maternal intake of palm oil or interesterified fat, substitutes for trans-unsaturated fatty acids (FA), induces metabolic changes in the adult offspring. During pregnancy and lactation, C57BL/6 female mice received normolipidic diets containing partially hydrogenated vegetable fat rich in trans-unsaturated fatty acids (TG), palm oil (PG), interesterified fat (IG) or soyabean oil (CG). After weaning, male offspring from all groups received the control diet until day 110. Plasma glucose and TAG and liver FA profiles were ascertained. Liver mitochondrial function was accessed with high-resolution respirometry by measuring VO2, fluorimetry for detection of hydrogen peroxide (H2O2) production and mitochondrial Ca2+ uptake. The results showed that the IG offspring presented a 20 % increase in plasma glucose and both the IG and TG offspring presented a 2- and 1·9-fold increase in TAG, respectively, when compared with CG offspring. Liver MUFA and PUFA contents decreased in the TG and IG offspring when compared with CG offspring. Liver MUFA content also decreased in the PG offspring. These modifications in FA composition possibly affected liver mitochondrial function, as respiration was impaired in the TG offspring and H2O2 production was higher in the IG offspring. In addition, mitochondrial Ca2+ retention capacity was reduced by approximately 40 and 55 % in the TG and IG offspring, respectively. In conclusion, maternal consumption of trans-unsaturated and interesterified fat affected offspring health by compromising mitochondrial bioenergetics and lipid metabolism in the liver.

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Zhurba, Olga M., A. V. Merinov, A. N. Alekseyenko et S. F. Shayakhmetov. « NAIMENOVANIE_STATII ». Hygiene and sanitation 98, n^o 10 (15 octobre 2019) : 1037–42. http://dx.doi.org/10.18821/0016-9900-2019-98-10-1037-1042.

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Introduction. Snow cover can be considered a reliable index of air pollution, it provides information on the spatial distribution of chemical compounds and the intensity of exposure to emission sources over a certain period. The need for snow cover studies is connected with the fact that precipitation not only reflects the state of atmospheric air, but also is a component of the balance of surface waters, and affects the state of soils, vegetation, and groundwater. Priority pollutants accumulated in the snow cover include polycyclic aromatic hydrocarbons (PAHs) and petroleum hydrocarbons (PHs), posing a public health hazard in urban areas. Materials and methods. To assess the level of contamination of different areas of snow cover in the zones, 9 sites were selected at different distances from stationary sources. Sampling was carried out in the period of maximum snow accumulation in the form of cores over the entire depth. There were used methods of gas chromatography-mass spectrometry, fluorimetry. Results. The data on the content of PAH and PHs in the snow cover of the city of Shelekhov of the Irkutsk region are presented. The rates of atmospheric deposition of PAHs, determined by their concentrations in the snow cover, were established to be high in this area. The maximum content of the amount of PAH - 134.7 µg/l and 78.0 µg/l, petroleum hydrocarbons 0.98 µg/l and 0.32 µg/l was found in the levels closest to stationary sources. The total content of benzo(a)pyrene at all points exceeds the background value on average 10.6-29.4 times. Conclusion. The data on the content of PAH and PH in the snow cover of the town of Shelekhov of the Irkutsk region are presented. Rates of atmospheric deposition of PAHs, determined by their concentrations in the snow cover, were established to be high in this area. The maximum content of the amount of PAH - 134.7 µg/l and 78.0 µg/l, petroleum hydrocarbons 0.98 µg/l and 0.32 µg/l was found in the levels closest to stationary sources. The total content of benzo(a)pyrene at all points exceeds the background value on average by 10.6-29.4 times.

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Algarra, Manuel, Victoria Jiménez, Philippe Fornier de Violet et Michel Lamotte. « Detection and quantification of PAH in drinking water by front-face fluorimetry on a solid sorbent and PLS analysis ». Analytical and Bioanalytical Chemistry 382, n^o 4 (14 mai 2005) : 1103–10. http://dx.doi.org/10.1007/s00216-005-3199-z.

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., F. I. Obahiagbon, P. Oviasogie ., M. E. Ukhun . et P. N. Oviawe . « Comparative Studies of the Thiamine and Riboflavin Contents in the Sap of Raphia hookeri Palm-by the Applications of Fluorimetric Method and Arrhenius Equation ». Trends in Applied Sciences Research 2, n^o 3 (1 mars 2007) : 260–63. http://dx.doi.org/10.3923/tasr.2007.260.263.

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Петров, Валерий Семёнович, Алиса Евгеньевна Мишко, Мария Андреевна Сундырева, Дамир Муратович Цику, Анна Александровна Марморштейн et Алла Анатольевна Полулях. « Physiological adaptation and photosynthesis characteristics of new hybrid forms of table grapes in summer period ». Magarach Vinogradstvo i Vinodelie, n^o 1(115) (22 mars 2021) : 15–20. http://dx.doi.org/10.35547/im.2021.22.94.002.

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Представлены результаты исследования физиологических особенностей восьми новых перспективных гибридных форм и одного сорта винограда столового направления использования в сравнении с контрольным сортом Ливия. Исследования новых форм, привитых на подвое Берландиери × Рипариа SО4, выполнены в агроэкологических условиях Центральной зоны виноградарства Краснодарского края. Для определения эффективности фотосинтеза использовали два параметра - квантовый выход фотохимической реакции фотосистемы II и содержание хлорофиллов a и b . Определение флуоресценции хлорофилла a проводили согласно методу PAM-флуориметрии. Содержание пигментов в листьях винограда оценивали спектрофотометрическим методом. Степень повреждения клеточных мембран в результате окислительного стресса устанавливали по содержанию малонового диальдегида в модельном опыте. Относительное содержание воды в листьях (RWC) оценивали по степени насыщения клеток водой и способности ее удерживать при высушивании согласно общепринятой методике. Выделены четыре группы гибридных форм винограда: 1) с высоким адаптивным и продукционным потенциалом (низкие значения МДА и высокие значения содержания пигментов, RWC и уровня флуоресценции хлорофилла a ) - сорт Дубовский розовый; 2) с высоким адаптивным потенциалом, но со средними показателями фотосинтеза - гибрид Арабелла; 3) с усредненными показателями, приближенными к контрольному сорту - Агат Дубовский и Гамлет; 4) с разнородными показателями фотосинтеза и относительного содержания воды и высоким уровнем окислительного стресса - Исполин, Кишмиш Дубовский, Пестрый, Тимоти. По содержанию хлорофиллов a и b и малонового диальдегида выявлена наибольшая вариабельность значений среди исследованных форм винограда, а такие показатели как относительное содержание воды в листьях и уровень флуоресценции хлорофилла a характеризовались достаточно однородными величинами. The results of the study of physiological characteristics of eight new promising table hybrid forms and one table grape variety in comparison with the control table variety ‘Livia’ are presented. Analyses of new forms grafted on the rootstock of ‘Berlandieri × Riparia SO4’ were carried out in agroecological conditions of the Central zone of viticulture in the Krasnodar Region. To determine the efficiency of photosynthesis, two parameters were used - the quantum yield of photochemical reaction of photosystem II and the content of chlorophylls a and b . The fluorescence of chlorophyll a was determined according to the PAM-fluorimetry method. The content of pigments in grape leaves was evaluated by spectrophotometric method. The degree of damage to cell membranes as a result of oxidative stress was determined by the content of malondialdehyde in the model experiment. The relative water content in leaves (RWC) was estimated by the degree of saturation of the cells with water and the ability to retain it during drying according to the generally accepted method. Four groups of hybrid forms of grapes are distinguished: 1) with high adaptive and productive potential (low values of MDA and high of pigment content, RWC and the level of fluorescence of chlorophyll a ) - ‘Dubovskiy Rozovyi’ variety; 2) with high adaptive potential, but with average values of photosynthesis - ‘Arabella’ hybrid; 3) with average values similar to the control variety - ‘Agat Dubovskiy’ and ‘Hamlet’; 4) with heterogeneous rates of photosynthesis and relative water content, and high levels of oxidative stress - ‘Ispolin’, ‘Kishmish Dubovskiy’, ‘Pestryi’, ‘Timoti’. According to the content of chlorophylls a and b and malondialdehyde, the greatest variability of values among the studied grape forms was revealed, and such indicators as the relative water content in leaves and the level of chlorophyll a fluorescence were characterized by fairly homogeneous quantities.

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Sychik, S. I., Natallia A. Dalhina, E. V. Fedorenko et L. L. Belysheva. « HYGIENIC CHARACTERISTIC OF THE CONTAMINATION LEVELS BY POLYCYCLIC AROMATIC HYDROCARBONS OF FOOD ». Hygiene and sanitation 98, n^o 7 (28 octobre 2019) : 771–76. http://dx.doi.org/10.18821/0016-9900-2019-98-7-771-776.

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Introduction. Foods are one of the main ways of entering chemical contaminants in the human body. Such compounds include polyaromatic hydrocarbons (PAHs), in particular, benzo(a)pyrene (BP), which according to the classification of the International Agency for Research on Cancer belongs to the 1 group of carcinogenic substances for humans. Material and methods. the levels of contamination of BP and the sum of 4PAНs (BP, benzo(a)anthracene (BaA), benz(b)fluoranthene (BbF), chrysene (CHR)) were studied for products of cocoa processing, smoked meat and fish products, fat-and-oil products and smoked cheeses. The determination of these compounds was carried out using the high-performance liquid chromatography method with a fluorimetric detector. A total of 147 samples of food products were examined. Simulation of the quantitative characteristics of samples that are «qualified» as «below limit of detection» or «not detected» is performed in accordance with the recommendations of FAO/WHO and EFSA. Results. The average levels of BP contamination and the 4PAHs median were from 0.0065 μg/kg and 0.26 μg/kg in cocoa products to 0.20 μg/kg and 3.72 μg/kg in fat-and-oil products, respectively. High, approaching the maximum, contamination levels of BP reached 1.29 μg/kg in fat-and-oil products, and the sum of 4PAHs was 7.87 μg/kg in smoked fish products. The highest levels of contamination of BP were observed in cocoa butter (2.11 μg/kg), in mayonnaise (1.45 μg/kg), in margarine (1.29 μg/kg), and the sum of 4PAHs - in pork chips of smoked sausages (10.11 μg/kg), in cocoa butter (9.27 μg/kg), in poultry snacks (7.77 μg/kg). Hygienic evaluation of the results didn’t reveal an excess of the maximum allowable levels of BP and the amount of 4PAH in all samples of food products studied. Conclusions. Due to the high hygienic importance of the compounds under discussion with carcinogenic properties, it is necessary to assess the health risk associated with the presence of these compounds in food products, taking into account the PAH mixture, depending on their individual contribution to the overall level of nutritional load and varying degrees of carcinogenic activity. It is necessary to develop and implement measures to reduce their level in the diet.

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Gopal, Leela, V. V. Hanuman et G. Chakrapani. « Separation Cum Pre-Concentration Technique for Determination of Uranium in Sea, Brine and Ground Water at Nano to Sub nanogram Levels ». International Journal of Scientific Research in Science and Technology, 25 mars 2020, 302–12. http://dx.doi.org/10.32628/ijsrst207246.

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Investigations were carried out for separation/pre concentration of uranium from aqueous solutions of different TDS using Powdered Activated Carbon (PAC). Parameters like amount of PAC, contact time, pH, volume of solutions and reagents for desorption were optimized. The sorption of uranium is more than 95% at pH 4-5 using 0.5 gram PAC with a contact time of 10 minutes. The sorbed uranium on PAC is recovered using 0.8N HNO<sub>3</sub> and determined by LED Fluorimetry. Method was successfully applied to ground water, sea water and brine water. Methodology is simple, selective, cost effective with minimal skills. RSD of the method varies ± 6-14 %.

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