Eco-friendly processes for the synthesis of amorphous calcium carbonate nanoparticles in ethanol and their stabilisation in aqueous media

New understandings in the amorphous calcium carbonate nanoparticle synthesis lead to a final mass concentration increase by a factor of 3.5. The stabilisation in aqueous media is achieved by a 2-minute scalable process using bio-sourced stabilisers.

The Beer Phenolic Profile Change During «Dry» Hopping in the Post-fermentation Stage Conditions

Статья посвящена вопросу изменения фенольного профиля пива в условиях «холодного» охмеления во время дображивания пива. Оценено влияние метаболизма дрожжевых клеток и типа хмеля во время дображивания на изменение общего количества полифенолов, изоксантогумола, изогумулона, кверцетина и рутина. Показано, что применение низовой расы дрожжей Rh и горького типа хмеля Mагнум позволяет добиться высокого (до 123,0 мг/дм3) содержания полифенолов в пиве к 1 сут «холодного» охмеления в отличие от тонко-ароматного хмеля Tетнангера, применение которого дает максимум количества полифенолов к 14 сут процесса. Применение верховой расы дрожжей Nottinghem приводит к замедлению увеличения концентрации полифенолов в среде, поскольку только к 7-14 сут вне зависимости от типа хмеля происходит их накопление. Показана зависимость в течение первых 14 сут изменения количества изоксантогумола от расы дрожжей и типа хмеля, а в последующем - только от типа хмеля. Авторами получены результаты, свидетельствующие о том, что кверцетин не вовлекается низовыми дрожжами в метаболический цикл, в отличие от верховых. Изменение концентрации рутина в пиве не зависит от расы дрожжей, и определяется своим содержанием в хмеле определенного типа. В работе показана взаимосвязь между процессами изменения содержания изогумулона и изоксантогумола при «холодном» охмелении в зависимости от ряда факторов. Проведение органолептического анализа позволило соотнести балловую оценку дескрипторов пива с основными показателями фенольного профиля. The article is devoted to the issue of beer phenolic profile changing in the conditions of «dry» hopping during the after-fermentation of beer. The influence of the yeast cells metabolism and the hop type during fermentation on the change in the polyphenol, isoxanthohumol, isogumulone, quercetin and rutin total amount, was evaluated. It has been shown that the Rh lager yeast race use and the Magnum bitter hop type makes it possible to achieve a high (up to 123.0 mg/dm3) polyphenol content in beer by 1 day of «dry» hopping, in contrast to the finely aromatic Tettnanger hops, the use of which gives the maximum polyphenol amount by 14 days of the process. The Nottinghem ale yeast race use leads to a slowdown in the polyphenol concentration increase in the medium, since their accumulation occurs only by 7-14 days, regardless of the hop type. The dependence during the first 14 days of the change in the isoxanthohumol amount on the yeast race and the hop type, and subsequently - only on the hop type was shown. The authors obtained results indicating that quercetin is not involved in the metabolic cycle by lager yeast, in contrast to ale yeast. The change in the rutin concentration in beer does not depend on the yeast race and is determined by its content in a certain type of hop. The paper shows the relationship between the processes of changing the isogumulone and isoxanthohumol content during «dry» hopping, depending on several factors. Organoleptic analysis made it possible to correlate the beer descriptors scoring with the phenolic profile main indicators.

Conserved Mechanism of Bicarbonate-Induced Sensitization of CatSper Channels in Human and Mouse Sperm

To fertilize an egg, mammalian sperm must undergo capacitation in the female genital tract. A key contributor to capacitation is the calcium (Ca2+) channel CatSper, which is activated by membrane depolarization and intracellular alkalinization. In mouse epididymal sperm, membrane depolarization by exposure to high KCl triggers Ca2+ entry through CatSper only in alkaline conditions (pH 8.6) or after in vitro incubation with bicarbonate (HCO3–) and bovine serum albumin (capacitating conditions). However, in ejaculated human sperm, membrane depolarization triggers Ca2+ entry through CatSper in non-capacitating conditions and at lower pH (< pH 7.4) than is required in mouse sperm. Here, we aimed to determine the mechanism(s) by which CatSper is activated in mouse and human sperm. We exposed ejaculated mouse and human sperm to high KCl to depolarize the membrane and found that intracellular Ca2+ concentration increased at pH 7.4 in sperm from both species. Conversely, intracellular Ca2+ concentration did not increase under these conditions in mouse epididymal or human epididymal sperm. Furthermore, pre-incubation with HCO3– triggered an intracellular Ca2+ concentration increase in response to KCl in human epididymal sperm. Treatment with protein kinase A (PKA) inhibitors during exposure to HCO3– inhibited Ca2+ concentration increases in mouse epididymal sperm and in both mouse and human ejaculated sperm. Finally, we show that soluble adenylyl cyclase and increased intracellular pH are required for the intracellular Ca2+ concentration increase in both human and mouse sperm. In summary, our results suggest that a conserved mechanism of activation of CatSper channels is present in both human and mouse sperm. In this mechanism, HCO3– in semen activates the soluble adenylyl cyclase/protein kinase A pathway, which leads to increased intracellular pH and sensitizes CatSper channels to respond to membrane depolarization to allow Ca2+ influx. This indirect mechanism of CatSper sensitization might be an early event capacitation that occurs as soon as the sperm contact the semen.

Removal of silver nanoparticles using phytoremediation method

This paper presents on removal of silver nanoparticles using phytoremediation. In this study, floating macrophyte (Pistia stratiotes) was used for phytoremediation of silver nanoparticles. This study investigated the performance of Pistia stratiotes in the removal of silver nanoparticles using phytoremediation method. The silver nanoparticles were green synthesized by using Muntingia calabura sp. leaves as reducing and stabilizing agent. The silver nanoparticles were successful synthesized as a peak appeared at wavelength 450 nm by UV-Vis spectrophotometer, while Pistia stratiotes had been acclimatized in tank at laboratory. Similar size of Pistia stratiotes had been employed for investigation. Each selected Pistia stratiotes was placed in 5 L bottles water containing different concentration (0.5 ppm, 1.0 ppm, 2.0 ppm and 3.0 ppm) of silver nanoparticles. This study was evaluated using UV-Vis spectrophotometer for five days. The results showed that the highest removal was achieved 69.88% at concentration of 0.5 ppm. This percentage removal relatively decreased up to 55.61% as concentration increase at 3.0 ppm. These results prescribed that phytoremediation of silver nanoparticles by Pistia stratiotes can be considered to apply and implement in water environment for AgNPs removal.

Assessment of multiple boiling of potable water utilizing household kettles for consumption

Boiling potable water utilizing 11 household/office electrical kettles for sterilization and aesthetic purposes is common among all age groups. However, the effect of continued boiling of the same water multiple times utilizing household electrical kettles on potable water quality has not been investigated previously; thus, the current study experimentally investigates the effect of reboiling potable water seven times on potable water quality. Kettle H (Dexon) recorded the highest concentration increase in Cl− and of 62.5 and 104%, respectively. In the case of cations, kettles I (Dexon Glass) and H (Dexon) recorded the highest concentration values for Na+ (48.8 ppm) ion in comparison with Ca2+ (31.8 ppm; kettle K (Moulinex)) and Mg2+ (5.8 ppm; kettles I and H). Kettles A (Sharp) and E (Black + Decker) showed a total dissolved solids (TDS) value of 34 ppm and a pH value of 9.05, respectively, after the second boiling that is undesirable as per the permissible standards. It is observed that kettles with a water compartment made of stainless steel displayed values closer to the raw sample after one to two boiling as per anions, pH and TDS analyses. Moulinex, Tokyo, Wansa and Bosch showed the best results in the case of various analyses.

Vitamin A and E Homologues Impacting the Fate of Acrylamide in Equimolar Asparagine-Glucose Model System

This study aims to evaluate the influence of Vitamin A and E homologues toward acrylamide in equimolar asparagine-glucose model system. Vitamin A homologue as β-carotene (BC) and five Vitamin E homologues, i.e., α-tocopherol (AT), δ-tocopherol (DT), α-tocotrienol (ATT), γ-tocotrienol (GTT), and δ-tocotrienol (DTT), were tested at different concentrations (1 and 10 µmol) and subjected to heating at 160 °C for 20 min before acrylamide quantification. At lower concentrations (1 µmol; 431, 403, 411 ppm, respectively), AT, DT, and GTT significantly increase acrylamide. Except for DT, enhancing concentration to 10 µmol (5370, 4310, 4250, 3970, and 4110 ppm, respectively) caused significant acrylamide formation. From linear regression model, acrylamide concentration demonstrated significant depreciation over concentration increase in AT (Beta = −83.0, R2 = 0.652, p ≤ 0.05) and DT (Beta = −71.6, R2 = 0.930, p ≤ 0.05). This study indicates that different Vitamin A and E homologue concentrations could determine their functionality either as antioxidants or pro-oxidants.

Performance Evaluation of Soil Cell

Soil Cell is a novel Low-Impact Development practice that is suitable for densely developed urban environment. This thesis seeks to gain further understanding of soil cell’s performance in terms of water quality and quality control; and to assess the exfiltration performance of perforated pipe in soil cells by monitoring an active cell. The monitoring result showed that the cell was very effective in treating particulate (90% concentration reduction), metal (91% lead concentration reduction to 53% copper concentration reduction) and phosphorus (74% concentration reduction). The cell was ineffective in treating chloride (1% concentration increase, no statistical significance) and even caused nitrate leaching (65% concentration increase). Field performance of the soil cell indicated that the inflow perforated backed up frequently, restricting the flow into the cell but laboratory testing of the perforated pipes’ hydraulic performance confirms that the pipe has a sufficient capacity to convey the flows of up to 10 L/s.