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The lipid composition, presence of the biologically active substances and ability of lipids to the spontaneous aggregation in the water medium of the winter garlic (Allium sativum L.) was studied by TLC, UV-spectrometry with the Gauss mathematic analysis of spectra and dynamic light scattering methods It is shown that share of the more easily oxidizable fractions in the garlic phospholipids is 2.45 times greater than that for the more poorly oxidizable fractions. Mathematic analysis of the UV-spectra of the lipids solution in chloroform revealed the presence of compounds with a conjugated couple bonds and ketodienes and confirmed the literature data about absence of flavonoids. The hydrophilic biologically active compounds are found in a polar phase during extraction of lipids. Analysis of UV-spectrum of 20-hydroxyekdizone in chloroform which is detected in the garlic lipids was done. It was determined the substantial maximum absorption band shift of sterols in UV-spectra of the garlic lipids testifies to their participation with sphigolipids in the raft formation that is due to form of particles with the average diameters 160 nm and the low absolute value of ξ-potential from the garlic lipids in the water medium., Изучены состав липидов, наличие биологически активных веществ и способность липидов к спонтанной агрегации в водной среде озимого чеснока (Allium sativum L.), используя методы ТСХ, УФ-спектрометрии с математической обработкой спектров по Гауссу и динамическое рассеяние света. Показано, что в составе фосфолипидов чеснока суммарная доля более легкоокисляемых фракций в 2.45 раза выше, чем более трудноокисляемых фракций. Математическая обработка УФ-спектров раствора липидов в хлороформе выявила наличие соединений с сопряженными двойными связями и кетодиенов и подтвердила данные литературы об отсутствии флавоноидов. Гидрофильные биологически активные соединения в процессе выделения липидов остаются в полярной фазе. Проанализирован УФ-спектр в хлороформе присутствующего в липидах чеснока 20-гидроксиэкдизона. Обнаружен существенный сдвиг максимума его полосы поглощения в УФ-спектре липидов чеснока, что свидетельствует об участии растительных стеринов в образовании рафтов и обусловливает формирование липидами чеснока в водной среде частиц со средним диаметром 160 нм и низкой абсолютной величиной ξ-потенциала.

The extractions of biologically active substances from aerial part of Tamarix hispida Willd. over ultrasound have been studied. The results showed that the output of extractive substances using ultrasound was increased to 37.34% under the following conditions: 10% ethyl alcohol in a raw-extractant ratio (1:6) for 25 minutes at a 20–25°С temperature and an ultrasound frequency of 35 kHz. The extraction was compared with maceration by yield and chemical composition. As a result of optimization, the output of components from the raw material is increased by 3–4 times at ultrasound frequency from 20 to 35kHz and extraction time is significantly reduced from 48 hours to 30 minutes. It was found that the major substances were hydrolyzable tannins, the content of which are 10% (ultrasonic extraction) and 8% (maceration), respectively. Using UV-spectrometry, it was confirmed that the appearance of a characteristic maximum in the spectrum of the substance to be analyzed corresponds to the area of absorption of gallic acid and its derivatives, which indicates the content of these in the structure of hydrolyzable tannins. The substance shown significant antidiabetic activity (in vitro) at IC 50 = 3.94±0.14 μg/ml., Приведены исследования по экстрагированию биологически активных веществ из надземной массы Tamarix hispida Willd. с применением ультразвукового воздействия. Результаты показали, что выход экстрактивных веществ с применением ультразвука увеличивается до 37.34% при следующих условиях: 10%-ный этиловый спирт в соотношении сырье-экстрагент (1:6) в течение 25 мин при температуре 20–25°С и частоте ультразвука 35 кГц. Экстракцию компонентов сравнивали с мацерацией по выходу и химическому составу. В результате оптимизации увеличен выход компонентов из исследуемого сырья в 3–4 раза при излучаемой мощности ультразвука от 20 до 35 кГц и значительно сокращено временя экстракции от 48 ч до 30 мин. Методом хроматографии идентифицировали мажорные компоненты – дубильные вещества, содержание которых составляет 10% (ультразвуковая экстракция) и 8% (мацерация) соответственно. Используя метод УФ-спектрометрии, подтвердили, что появление характеристичного максимума в спектре субстанции соответствует области поглощения галловой кислоты и ее производных, что свидетельствует об их содержании в структуре гидролизуемых дубильных веществ. Полученная субстанция показала умеренный антидиабетический эффект (in vitro) при ИК50 = 3.94±0.14 мкг/мл.

Lead dioxide, a lead corrosion product, is an important contributor to residential drinking water contamination. A neurotoxin and endocrine disruptor, lead poses serious human health concerns. Despite previous research on water distribution pipes, lead in water heating and softening systems is unexplored. Standard tank water heaters and water softeners have significantly different aquatic environments compared to distribution pipes, due to increased temperature and ion concentration levels. This research verifies the iodometric method for lead dioxide detection and quantifies total lead and dissolved lead(IV) ions over time in simulated water heater and softener environments. Initial experiments confirmed the iodometric method for lead(IV) and measured absorbance with UV-spectrometry. Another set of experiments quantified the dissolved lead(IV) cation in a filtered lead-water mixture by applying the iodometric method to batch reactors, and varying water source (DI, synthetic tap water), temperature (25, 55°C), and NaCl concentration (0.175, 0.584 g/L). Furthermore, each sample was analyzed by ICP-OES to determine the concentration of elemental lead present. The iodometric method resulted in an 80% recovery of dosed lead over one hour. Dissolved lead(IV) ion, conversely, had very little recovery after a week in each batch reactor. Overall, the iodometric method is an accurate and rapid tool for quantifying and comparing dissolution kinetics of total lead dioxide. In contrast, at the temperatures and ionic strength levels investigated, lead(IV) cations may exist in such low concentrations that iodometry may not be an accurate detection method. Future research should consider additional lead species for complete lead dissolution models of water heating and softening systems.

Indirect UV-absorption spectrometry was shown to be a valuable tool for chemical characterization of functionalized carbon nanotubes (CNTs). It complements data from X-ray photoelectron spectroscopy (XPS) or FTIR analysis since it helps to clarify the type and concentration of functional groups. The principles of indirect application of UV-spectrometry and its mathematical interpretation are discussed. Their facile application, together with their adequate sensitivity and high flexibility, make UV-absorption-based approaches a valuable alternative to fluorescence spectrometry. Here, the approach was applied to the chemical analysis of oxidizing substances on CNTs. For this, pristine CNTs of low but finite oxygen content as well as brominated CNTs were analyzed by reaction in suspension with UV-active thiol reagents and a styrene derivative. It was shown that carefully selected reagents allow differentiation and quantification of bromine and generally oxidizing entities like oxygen. For brominated CNTs, it was shown that physisorbed bromine may dominate the overall bromine content.