Extraction of pyridine using systems based on water-soluble polymers

In the process of using hydrocarbon fractions containing a large amount of nitrogenous compounds, nitrogen oxides are released into the atmospheric air, which have a negative impact on the environment and human health. The traditional cleaning method is treatment with a 25% sulfuric acid solution and subsequent hydrotreating. However, this process becomes disadvantageous due to its inability to achieve ultra-low concentrations of nitrogen-containing compounds (<10 ppm). Extraction using non-toxic and environmentally friendly water-soluble polymers is a promising alternative compared to traditional methods. This work presents the dependence of the interphase distribution of pyridine on the composition of extraction systems based on water-soluble polymers. According to the results of the study, it was found that polyethylene glycol-400, polypropylene glycol-425 and methyl ether of polyethylene glycol-350 exhibit effective extraction properties in relation to pyridine and extract it by 90.95%, 90.33% and 87.82% in one extraction stage, respectively. It was also found that the use of two-phase aqueous systems based on water-soluble polymers in the process of extracting pyridine is promising.

Effective Purification of Eutrophic Wastewater from the Beverage Industry by Microbubbles

Beverage industries often discharge large amounts of organic matter with their wastewater. Purification of the effluent is their obligation, but it is nontrivial. Among wastewater components, removal of dissolved organic matter often requires much effort. Therefore, a special effective technique must be considered. Microbubbles (1–100 μm) have several special properties of relevance to wastewater treatment. In this study, the effectiveness of microbubbles for treating and purifying beverage wastewater was evaluated. Orange juice, lactic acid drink, and milk were used as model substrates of dissolved organic matter, and degradation experiments were carried out. Rates of air supply by microbubbles were 0.05% (air/wastewater) min−1. Results indicated that the total organic carbon (TOC) in an experimental vessel containing milk (high nitrogen content) decreased by 93.1% from 11.0 to 0.76 g during a 10-day incubation. The TOC of lactic acid drink (least nitrogen content) decreased by 66.3%, from 15.6 to 5.26 g, and the TOC of orange juice (medium nitrogen content) decreased by 82.7%, from 14.8 to 2.55 g. Large amounts of particulate organic matter floated on the water surface in the milk with microbubbles and were removed easily, while almost no floating materials were observed in the orange juice and lactic acid drink. In contrast, in the macrobubble treatment (diameter 0.1 to 2 mm), only 37.0% of TOC in the milk was removed. Whereas the macrobubble treatments were anaerobic throughout the incubations, the microbubble treatments returned to aerobic conditions quickly, and brought 10 times greater bacterial abundances (>108 cells mL−1). These results suggest that microbubbles are much superior to macrobubbles in supplying oxygen and accelerating the growth of aerobic bacteria, and that wastewater containing more nitrogenous compounds was purified more effectively than that with less nitrogen by microbial degradation and floating separation.

Role of Nitrogen Compounds in Forming the Quality of Red Sparkling Wine

В технологии игристых вин азотистые соединения, в том числе их концентрация и качественный состав, играют существенную роль на всех этапах производственного процесса. Цель работы состояла в исследовании изменения азотсодержащих соединений в процессе вторичного брожения и их влияния на качественные характеристики красного игристого вина. В качестве объектов исследования в работе использованы пять промышленных образцов сортовых виноматериалов, соответствующих требованиям нормативной документации по физико-химическим и органолептическим показателям, и пять купажей, составленных из этих виноматериалов, а также опытные образцы игристых вин, полученные в результате вторичного брожения в бутылках. Определение массовой концентрации аминного азота проводили методом йодометрического титрования, аммиачного азота - диффузионным методом. Исследование качественного состава и концентрации аминокислот проводили с использованием ВЭЖХ на приборе «Аgilent Technologies 1200 Series» (Agilent, США). Установлено, что концентрация аммиачного азота в исследованных образцах варьировала от 13,4 до 29,7 мг/дм3, аминного азота - от 53,2 до 364,0 мг/дм3, свободных аминокислот - от 267,4 до 615,4 мг/дм3. Показано, что в результате вторичного брожения снижается суммарная концентрация аминокислот, причем наиболее сильно - в образцах с низким содержанием неорганического азота менее 20,0 мг/дм3. В образцах с высоким содержанием фенольных веществ снижение концентрации аминокислот происходило за счет образования с ними комплексных соединений. Показано, что состав азотистых соединений и соотношение свободных аминокислот в исходных виноматериалах оказывает влияние на образование отдельных ароматобразующих летучих компонентов и формирование типичных свойств красного игристого вина. Рекомендовано использовать показатели массовой концентрации аминного и аммиачного азота, а также состав и концентрацию свободных аминокислот в качестве дополнительных критериев оценки виноматериалов для выработки высококачественных красных игристых вин. In the technology of sparkling wines, nitrogenous compounds, including their concentration and qualitative composition, play an essential role at all stages of the production process. The aim of the work was to study the changes in nitrogen-containing compounds during secondary fermentation and their effect on the qualitative characteristics of red sparkling wine. As objects of research, five industrial samples of varietal wine materials that meet the requirements of regulatory documentation on physico-chemical and organoleptic indicators, and five blends made up of these wine materials, as well as experimental samples of sparkling wines obtained as a result of secondary fermentation in bottles, were used in the work. Determination of the mass concentration of amine nitrogen was carried out by iodometric titration, ammonia nitrogen - by diffusion method. The study of the qualitative composition and concentration of amino acids was carried out using HPLC on the device «Agilent Technologies 1200 Series» (Agilent, USA). It was found that the concentration of ammonia nitrogen in the studied samples varied from 13.4 to 29.7 mg/dm3, amine nitrogen - from 53.2 to 364.0 mg/dm3, free amino acids - from 267.4 to 615.4 mg/dm3. It is shown that as a result of secondary fermentation, the total concentration of amino acids decreases, and most strongly in samples with a low content of inorganic nitrogen less than 20.0 mg /dm3. In samples with a high content of phenolic substances, the concentration of amino acids decreased due to the formation of complex compounds with them. It is shown that the composition of nitrogenous compounds and the ratio of free amino acids in the initial wine materials influence the formation of individual aroma-forming volatile components and the formation of typical properties of red sparkling wine. It is recommended to use indicators of the mass concentration of amine and ammonia nitrogen, as well as the composition and concentration of free amino acids as additional criteria for evaluating wine materials for the production of high-quality red sparkling wines.

Advances in treatment of coking wastewater – a state of art review

Coking wastewater poses a serious threat to the environment due to the presence of a wide spectrum of refractory substances such as phenolic compounds, polycyclic aromatic hydrocarbons and heterocyclic nitrogenous compounds. These toxic substances are difficult to treat using conventional treatment methods alone. In recent years much attention has been given to the effective treatment of coking wastewater. Thus, this review seeks to provide a brief overview of recent developments that have taken place in the treatment of coking wastewater. In addition, this article addresses the complexity and the problems associated with treatment followed by a discussion on biological methods with special focus on bioaugmentation. As coking wastewater is refractory in nature, some of the studies have been related to improving the biodegradability of wastewater. The final section focuses on the integrated treatment methods that have emerged as the best solution for tackling the highly unmanageable coking wastewater. Attention has also been given to emerging microwave technology which has tremendous potential for treatment of coking wastewater.

Natural Product Studies on the Hamigerans

<p>This study describes the NMR-directed isolation and structural elucidation of several new and semi-synthesised compounds. Carrying on from the previous examinations on the sponge Hamigera tarangaensis undertaken at VUW resulted in the isolation of an additional seven congeners to the hamigeran family. These included three debrominated analogues (37, 60, 62), an alternative methyl ester analogue (63) and a 4-brominated analogue (64). Two structures with novel functionality were also isolated, which were found in fractions previously not investigated, the nitrile containing hamigeran R (61) and the dimer hamigeran S (65). The isolation of these novel compounds led to the proposal of a biosynthesis from a reaction with hamigeran G (40) and ammonia, similar to the previous nitrogenous hamigerans biosynthesis with amino acids. Semi-synthesis was undertaken to probe the biosynthesis of these and the other nitrogenous compounds. The results of this produced four new compounds: two imine intermediates, hamigeran G imine (66) and hamigeran B imine (70), a glycine derived hamigeran (68) and the hamigeran D epimer (69).</p>

Natural Product Studies on the Hamigerans

<p>This study describes the NMR-directed isolation and structural elucidation of several new and semi-synthesised compounds. Carrying on from the previous examinations on the sponge Hamigera tarangaensis undertaken at VUW resulted in the isolation of an additional seven congeners to the hamigeran family. These included three debrominated analogues (37, 60, 62), an alternative methyl ester analogue (63) and a 4-brominated analogue (64). Two structures with novel functionality were also isolated, which were found in fractions previously not investigated, the nitrile containing hamigeran R (61) and the dimer hamigeran S (65). The isolation of these novel compounds led to the proposal of a biosynthesis from a reaction with hamigeran G (40) and ammonia, similar to the previous nitrogenous hamigerans biosynthesis with amino acids. Semi-synthesis was undertaken to probe the biosynthesis of these and the other nitrogenous compounds. The results of this produced four new compounds: two imine intermediates, hamigeran G imine (66) and hamigeran B imine (70), a glycine derived hamigeran (68) and the hamigeran D epimer (69).</p>

BIOLOGICALLY ACTIVE COMPONENTS OF THE EREMURUS HISSARICUS ROOT

Полисахариды из растений E. hissaricus, которые наиболее распространены в районе южного склона Гиссарского хребта Республики Таджикистан, недостаточно исследованы. В доступной литературе сведения по вопросам выделения и очистки, а также физико-химических свойств полисахаридов из корнеклубней E. hissaricus отсутствуют. К тому же не исследовались вопросы выделения и изучения основных компонентов биохимических соединений, таких как жировая фракция, фенольные, азотистые соединения и белки, водорастворимые сахара, а также моно-, олиго- и полисахариды из целых корней E. hissaricus в разных фазах развития, что и явилось целью данной работы. Для изучения использовали корни E. hissaricus, выращенного на высокогорной биологической станции Сиякух Института ботаники, физиологии и генетики растений АН РТ (южный склон Гиссарского хребта, 2200 м над уровнем моря). Исследовано содержание основных компонентов биохимических соединений – жировая фракция, фенольные соединения, белки и азотистые соединения, водорастворимые сахара, а также полисахариды из корней эремуруса гиссарского в разные периоды развития. Установлено, что в фазе покоя содержание жировой фракции, фенольных соединений и водорастворимых сахаров в корнях эремуруса гиссарского увеличивается по отношению к другим фазам. Polysaccharides from plants of E. hissaricus which are most widespread in the region of the southern slope of the Gissar Range of the Republic of Tajikistan, are insufficiently investigated. In available literature of the data concerning selection and cleaning and also physical and chemical properties of polysaccharides from korneklubny E. hissaricus are absent. Besides questions of selection and studying of principal components of biochemical connections, such as fatty fraction, phenolic, nitrogen compounds and proteins, water-soluble sugar and also mono-, oligo- and polysaccharides from the whole roots E. hissaricus in different phases of development were not investigated that is the purpose of this work. For studying used the roots E. hissaricus, grown up at the mountain biological station Siyakukh at Institute of botany, physiology and genetics of plants of AN of RT (the southern slope of the Gissar Range, 2200 m above sea level). The content of the main biochemical compounds – fat fraction, phenolic compounds, proteins and nitrogenous compounds, water-soluble sugars, as well as polysaccharides from whole roots of E. hissaricus in different periods of development has been studied. It was found that in the deep-dormant phase the content of fat fraction, phenolic compounds and water-soluble sugars in the roots of E. hissaricus increases in relation to other plant grows phases.

Evaluation of health benefits of sea lamprey (Petromyzon marinus) isolates using in vitro antiinflammatory and antioxidant assays

Sea lamprey (Petromyzon marinus), a parasitic fish which survives on blood of other fishes, is consumed as a delicacy in many countries. Our earlier studies on sea lamprey compounds that showed potential to deter adult sea lampreys yielded several sterols, glycerides, free fatty acids, amino acids, organic acids and nitrogenous compounds. Therefore, this study was to assess the health-benefits of these compounds including additional isolates from HPLC fractions that kept aside due to lack of activity in sea lamprey deterrent assays. In vitro cyclooxygenase enzymes (COX-1 and -2) and lipid peroxidation (LPO) inhibitory assays, respectively, were used to determine antiinflammatory and antioxidant activities. Among the tested sterols, cholesteryl eicosapentaenoate and cholesteryl arachidonate exhibited IC50 values of 14.6 and 17.7 μg/mL for COX-1 and 17.3 and 20.8 μg/mL for COX-2, respectively. Cholesteryl palmitate and cholesteryl oleate showed moderate COX-1 and COX-2 enzyme inhibition at 25 μg/mL. Amino acids arginine, tyrosine, glutamic acid, tryptophan and asparagine also showed moderate COX-1 and COX-2 inhibition at the same concentration. Among the twelve new isolates from fractions that we did not investigate earlier, a novel uracil derivative petromyzonacil showed COX-1 and COX-2 inhibition at 25 μg/mL by 35 and 15%, respectively. Cholesterol esters tested at 25 μg/mL exhibited LPO inhibition between 38 and 82 percent. Amino acids cysteine, methionine, aspartic acid, threonine, tryptophan, histidine, glutamic acid, phenylalanine and tyrosine at 25 μg/mL showed LPO inhibition between 37 and 58% and petromyzonacil by 32%. These assay results indicate that consumption of sea lamprey offer health-benefits in addition to nutritional benefits.

Plant secondary metabolite diversity reflects both phylogeny and ecological adaptation

A phylogenetic framework explaining plant secondary metabolite diversity is lacking, but metabolite classes could represent adaptations to habitat resource availability. We test the hypothesis that primary adaptive strategies (competitors, C; stress-tolerators, S; ruderals, R) are associated, respectively, with nitrogenous metabolites synthesized in persistent organs (alkaloids), nitrogen-lacking aromatic terpenes and phenolics, and nitrogenous compounds prevalent in reproductive tissues (cyanogenic glucosides and glucosinolates). A matrix was compiled of 1019 species for which secondary metabolite pathways and CSR strategies are known. Accounting for phylogenetic relatedness and native biomes, we found that most phytochemical pathways did not correlate with strategy axes, but certain key associations were evident. C-selection was positively associated with amino acid-derived phenylpropanoids (low phylogenetic relatedness; λ<0.5) and pyrrolizidine alkaloids and galloyl derivatives (high λ), and negatively with N-lacking linear monoterpenes (low λ). Nitrogenous cyanogenic glucosides positively correlated with R-selection (low λ). Terpenoids were widely distributed, but correlated positively with S- and negatively with R-selection (low λ). Twenty-six correlations between phytochemicals and biomes (low λ) were evident. Most secondary metabolite synthesis pathways are widespread, reflecting common roles and obligate defence, and strong phylogenetic effects are often evident. However, the character of phytochemical/adaptive strategy associations agrees with ecological theory and thus reflects adaptation.