Evaluation of some physico-chemical techniques for the determination of the fraction of dissolved copper toxic to the marine diatom nitzschia closterium

1983 ◽  
Vol 151 ◽  
pp. 281-295 ◽  
Author(s):  
T.M Florence ◽  
B.G Lumsden ◽  
J.J Fardy
2020 ◽  
Vol 32 (5) ◽  
pp. 1221-1229
Author(s):  
Satish Kumar ◽  
P.K. Santra ◽  
J. Dwivedi ◽  
R.C. Aryan

The present study reports the synthesis and characterization of novel molecules inhibiting the spread of hepatitis C. The molecules were designed as to block the NS3/4A protease enzyme on HCV RNA. The molecules were synthesized using usual peptide synthesis techniques. Compounds with purity more than 95% were characterized and docking studies were also performed. All the compounds were characterized using physico-chemical techniques such as determination of melting point by DSC and NMR, mass, IR spectral studies. The docking studies were also conducted to assess the activity of molecules for inhibition of hepatitis C virus.


2019 ◽  
Vol 15 (4) ◽  
pp. 312-318
Author(s):  
Shuoye Yang

Background: The therapeutic ability and application of antifungal peptide (APs) are limited by their physico-chemical and biological properties, the nano-liposomal encapsulation would improve the in vivo circulation and stability. </P><P> Objective: To develop a long-circulating liposomal delivery systems encapsulated APs-CGA-N12 with PEGylated lipids and cholesterol, and investigated through in vivo pharmacokinetics. Methods: The liposomes were prepared and characterized, a rapid and simple liquid chromatographytandem mass spectrometry (LC-MS/MS) assay was developed for the determination of antifungal peptide in vivo, the pharmacokinetic characteristics of APs liposomes were evaluated in rats. Results: Liposomes had a large, unilamellar structure, particle size and Zeta potential ranged from 160 to 185 nm and -0.55 to 1.1 mV, respectively. The results indicated that the plasma concentration of peptides in reference solutions rapidly declined after intravenous administration, whereas the liposomeencapsulated ones showed slower elimination. The AUC(0-∞) was increased by 3.0-fold in liposomes in comparison with standard solution (20 mg·kg-1), the half-life (T1/2) was 1.6- and 1.5-fold higher compared to the reference groups of 20 and 40 mg·kg-1, respectively. Conclusion: Therefore, it could be concluded that liposomal encapsulation effectively improved the bioavailability and pharmacokinetic property of antifungal peptides.


1997 ◽  
Vol 31 (10) ◽  
pp. 2435-2442 ◽  
Author(s):  
F. Pablo ◽  
J.L. Stauber ◽  
R.T. Buckney

2011 ◽  
Vol 17 (1) ◽  
pp. 107-115 ◽  
Author(s):  
Nada Babovic ◽  
Dejan Markovic ◽  
Vojkan Dimitrijevic ◽  
Dragan Markovic

This paper shows the results obtained in field analysis performed at the Tamis River, starting from the settlement Jasa Tomic - border between Serbia and Romania to Pancevo - confluence of Tamis into the Danube. The Tamis is a 359 km long river rising in the southern Carpathian Mountains. It flows through the Banat region and flows into the Danube near Pancevo. During the years the water quality of the river has severely deteriorated and badly affected the environment and the river ecosystem. In situ measurements enabled determination of physico-chemical parameters of water quality of the Tamis River on every 400 m of the watercourse, such as: water temperature, pH value, electrical conductivity, contents of dissolved oxygen and oxygen saturation. The main reason of higher pollution of Tamis is seen in connection to DTD hydro system. Sampling was performed at 7 points with regard to color, turbidity, total hardness, alkalinity, concentration of ammonium nitrogen, nitrite nitrogen, nitrate nitrogen, iron, chlorides and sulphates in samples. The aim of the present work was to evaluate water quality in the Tamis River taking into account significant pollution, which originates from settlements, industry and agriculture, and to suggest appropriate preventive measures to further pollution decreasing of the river's water.


Author(s):  
А.А. ГРЯЗНОВ ◽  
Ю.А. ЛЕТЯГО ◽  
О.А. ГРЯЗНОВА ◽  
Р.И. БЕЛКИНА

Исследовано влияние добавки микроводоросли спирулины в рецептуру хлеба из пшеничной муки, обогащенного обойной мукой из зерна ячменя сортов Гранал 32 и Нудум 95 и тритикале сорта Цекад 90, на показатели его качества. Размолотую до порошкообразного состояния спирулину в количестве 0,5 к массе муки вносили при замесе теста в три опытных образца: пшеничный хлеб, хлеб Гранал и Ясень , рецептуры которых были разработаны ранее. В качестве контрольного образца был хлеб из пшеничной муки высшего сорта без добавок. Лабораторную выпечку образцов хлеба проводили в соответствии с методикой госкомиссии по сортоиспытанию на лабораторном хлебопекарном оборудовании. В результате определения органолептических и физико-химических показателей качества готовой продукции установлено, что добавка спирулины к пшеничной муке повышает пористость мякиша хлеба и увеличивает его объем до 546 см3, что на 18 см3 больше, чем в контрольном образце. Достаточно высокий объем 494 см3 имел образец хлеба, в рецептуру которого входит ячменная мука с добавлением спирулины. Внесение спирулины в рецептуру существенно не повлияло на показатели влажности (4346) и кислотности хлеба, которые в опытных образцах соответствуют нормативам ГОСТ 2698786 на хлеб из пшеничной муки. Самую высокую общую оценку 4,2 балла по пятибалльной шкале получил образец хлеба с добавлением к пшеничной муке порошка спирулины. The effect of the addition of spirulina microalgae in the formulation of bread from wheat flour enriched with wholemeal flour from barley grain varieties Granal 32 and Nudum 95 and triticale varieties Tsekad 90, on the indicators of its quality has been studied. Spirulina ground to a powdered state in an amount of 0,5 by weight of flour was introduced when kneading the dough into the formulations of three samples: wheat bread, bread Granal and Yasen , the formulations of which were developed earlier. Bread from wheat flour of the highest grade without additives was as a control sample. Laboratory baking of bread samples was carried out in accordance with the methodology of the state Commission for variety testing on laboratory baking equipment. As a result of the determination of organoleptic and physico-chemical indicators of the quality of the finished product, it was found that the addition of spirulina to wheat flour increases the porosity of the bread crumb and increases its volume to 546 cm3, which is 18 cm3 more than in the control sample. A sample of bread, the formulation of which includes barley flour with the addition of spirulina, had a sufficiently high volume 494 cm3. Adding spirulina to the formulation did not significantly affect the moisture content (4346) and acidity of bread, which in the prototypes correspond to the standards of GOST 2698786 for bread made of wheat flour. A sample of bread with spirulina powder added to wheat flour had the highest overall score 4б2 points on a five-point scale.


Author(s):  
Victoriţa BONTA ◽  
Daniel Severus DEZMIREAN ◽  
Liviu Alexandru MĂRGHITAŞ ◽  
Adriana Cristina URCAN ◽  
Otilia BOBIŞ

Honey is used for centuries both as nutrient and in medicine, being an exhaustless source of benefic factors for health and also for different biotechnological processes. This is a complex matrix which possesses antioxidant and antimicrobial properties due to its peroxidic activity and bioactive compounds. A fully validated approach for the determination of sugars, hydroxymethylfurfural content and diastase activity in honey samples were presented in accordance with the official methods from the International Honey Commission. Spectrophotometric method was used for diastazic activity determination and chromatographic determinations for HMF content (photodiode array detection) and sugars (refractive index detection). The limits of detection and quantification were calculated. Accuracy, precision and uncertainty were determined in the spectrophotometric and chromatographic techniques using the certified reference material. Diastase activity, sucrose content and hydroxymethylfurfural (HMF) content were easily differentiated and these parameters were used for indication of a possible adulteration of the honey. The present study confirms that, in order to have an authentic honey sample, diastazic activity must be above 8 DN (diastazic number) and HMF content less than 40 mg/kg. Sugar spectrum is different for every honey type. Consequently, physico-chemical analysis should be combined for the determination of authentic honey and proper labeling.


Sign in / Sign up

Export Citation Format

Share Document