Simultaneous quantification of uranium(VI), samarium, nitric acid, and temperature with combined ensemble learning, laser fluorescence, and Raman scattering for real-time monitoring.

Laser-induced fluorescence spectroscopy (LIFS), Raman spectroscopy, and a stacked regression ensemble was developed for near real-time quantification of uranium(VI) (1-100 µg mL-1), samarium (0-200 µg mL-1) and nitric acid (0.1-4 M) with varying temperature (20 °C-45 °C). LIFS applications range from fundamental lab-scale studies to real-time process monitoring at industrial levels, such as nuclear reprocessing applications, provided the phenomena affecting the fluorescence spectrum are accounted for (e.g., absorption, quenching, complexation). Multiple chemometric models were examined and compared to a more traditional multivariate regression approach called partial least squares (PLS). Results obtained on synthetic samples selected using D-optimal experimental design indicated that a stacked regression method, which included ridge regression, random forest, PLS, and an eXtreme gradient boost algorithm, successfully measured uranium(VI) concentrations directly in nitric acid without measuring luminescence lifetimes or standard addition. The top model resulted in percent root-mean-square error of prediction values of 5.2, 1.9, 3.0, and 2.3% for U(VI), Sm3+, HNO3, and temperature, respectively. The approach may be useful for quantifying fluorescent fission products (e.g., Sm3+) to provide information on burnup of irradiated nuclear fuel. This novel framework reinforces the applicability of LIFS for real-time applications in nuclear fuel cycle applications.

Immunomulation effect of alginic acid and chitooligosaccharides in silver carp (Hypophthalmichthys molitrix).

Individual and combined efficacy of chitooligosaccharides (COS) and alginic acid (AA) at 1 g, 2 g, and 3 g per kg diet was assessed on growth and disease resistance in silver carp (Hypophthalmichthys molitrix) against Edwardsiella ictaluri. Growth parameters including specific growth rate (SGR), weight gain (WG), and feed conversion rate (FCR) were significant in fish fed 2 g and 3 g kg-1 of COS or AA, and fish fed combined COS + AA at 1, 2 and 3 kg-1 diet. In all groups, the survival rate (SR) was recorded 100%, except in group fed 2 g kg-1 AA diet. All the hematological and biochemical profiles significantly increased in groups fed 2 g and 3 g kg-1 of COS, AA, and COS + AA diets. Lipase and amylase enzyme activities and superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GPx) antioxidant enzyme activities were significantly increased in fish fed 2 g and 3 g kg-1 of COS, AA, and COS + AA diet. Respiratory burst (RB), lysozyme (Lyz), reactive oxygen species (ROS) activities, and immunoglobuline (Ig) level were enhanced significantly in fish fed 2 g kg-1 of COS or COS + AA and all 3 g kg-1 diets, whereas nitric acid (NO) production and serum AP activity were improved in 2 g kg-1 COS + AA and 3 g kg-1 COS or COS + AA diets. Pro-inflammatory cytokine such as IL-8 mRNA transcriptions was significant in 2 g kg-1 COS + AA diet and all 3 g kg-1 diet. The IL-10 anti-inflammatory cytokine mRNA transcriptions were significant in 3 g kg-1 COS or COS + AA diets. This study was confirmed that H. molitrix fed with 3 g kg-1 COS or COS + AA diets were better activity when compared to other diet.

Acid deposition at higher acidity weakens the antagonistic responses during the co-decomposition of two Asteraceae invasive plants.

Co-invasion by two invasive plant species (IPS) can occur in the same habitat. Diversified acid deposition may change the co-invasion process by altering litter decomposition and plant-soil feedback signalling. This study examined the co-decomposition of two Asteraceae IPS (Solidago canadensis L. and Bidens pilosa L.) on litter decomposition rate, soil enzyme activities, and soil N-fixing bacterial communities under diversified acid deposition (mixed acid deposition at pH 5.6 and at pH 4.5, sulfuric acid at pH 4.5, and nitric acid at pH 4.5). B. pilosa litter degraded faster than S. canadensis litter. Acid deposition at higher acidity accelerated the decomposition rate of both pure S. canadensis litter and the equally mixed litters from the two Asteraceae IPS. Antagonistic responses may occur during the co-decomposition of the two Asteraceae IPS with mixed acid deposition, regardless of the pH, as well as with nitric acid deposition at pH 4.5; in contrast, there may be neutral responses for the co-decomposition process with sulfuric acid at pH 4.5. The type of acid deposited may be one of the key factors affecting the intensity of the mixing effect affecting the co-decomposition. Acid deposition at higher acidity weakened the antagonistic responses for the co-decomposition of the two Asteraceae IPS compared with the response to weak acids. Together, these results indicate that acid deposition at higher acidity could facilitate the co-invasion of the two Asteraceae IPS mainly through accelerated litter decomposition as well as weakened antagonistic responses for co-decomposition.

PM2.5 in Carlsbad Caverns National Park: Composition, sources, and visibility impacts.

Carlsbad Caverns National Park in southeastern New Mexico is adjacent to the Permian Basin, one of the most productive oil and gas regions in the country. The 2019 Carlsbad Caverns Air Quality Study (CarCavAQS) was designed to examine the influence of regional sources, including urban emissions, oil and gas development, wildfires, and soil dust on air quality in the park. Field measurements of aerosols, trace gases, and deposition were conducted from 25 July through 5 September 2019. Here, we focus on observations of fine particles and key trace gas precursors to understand the important contributing species and their sources and associated impacts on haze. Key gases measured included aerosol precursors, nitric acid and ammonia, and oil and gas tracer, methane. High-time resolution (6-min) PM2.5 mass ranged up to 31.8 µg m-3, with an average of 7.67 µg m-3. The main inorganic ion contributors were sulfate (avg 1.3 µg m-3), ammonium (0.30 µg m-3), calcium (Ca2+) (0.22 µg m-3), nitrate (0.16 µg m-3), and sodium (0.057 µg m-3). The WSOC concentration averaged 1.2 µg C m-3. Sharp spikes were observed in Ca2+, consistent with local dust generation and transport. Ion balance analysis and abundant nitric acid suggest PM2.5 nitrate often reflected reaction between nitric acid and sea salt, forming sodium nitrate, and between nitric acid and soil dust containing calcium carbonate, forming calcium nitrate. Sulfate and soil dust are the major contributors to modeled light extinction in the 24-hr average daily IMPROVE observations. Higher time resolution data revealed a maximum 1-hr extinction value of 90 Mm-1 (excluding coarse aerosol) and included periods of significant light extinction from BC as well as sulfate and soil dust. Residence time analysis indicated enrichment of sulfate, BC, and methane during periods of transport from the southeast, the direction of greatest abundance of oil and gas development.Implications: Rapid development of U.S. oil and gas resources raises concerns about potential impacts on air quality in National Parks. Measurements in Carlsbad Caverns National Park provide new insight into impacts of unconventional oil and gas development and other sources on visual air quality in the park. Major contributors to visibility impairment include sulfate, soil dust (often reacted with nitric acid), and black carbon. The worst periods of visibility and highest concentrations of many aerosol components were observed during transport from the southeast, a region of dense Permian Basin oil and gas development.

Selective recovery of gold from dilute aqua regia leachate of waste printed circuit board by thiol-modified garlic peel.

Garlic peel (GP) was chemically modified by using thiourea under hydrothermal treatment, which could selectively adsorb gold ions from the 1/10 dilute aqua regia media directly without needing the dangerous evaporation operation. The synthetic chloroauric solution and practical leach liquor of the waste PCB (printed circuit board) powder in dilute aqua regia were employed to assess the adsorption performance on the thiol-GP and the commercial quaternary ammonia anion resin of D201, respectively. It was experimentally confirmed that the adsorption efficiency of gold onto the thiol-GP and D201 resin both reached 100%, and the maximum adsorption capacity of thiol-GP gel was evaluated as 42.59 mg Au/g that was much larger than that of D201 resin (3.33 mg Au/g). The thiol-GP gel adsorption efficiency of other coexisting base metal ions like Cu2+, Ni2+, Al3+, and Fe3+ from dilute aqua regia leach liquor of the waste PCB powder was near zero, and only gold could be enriched by selective adsorption onto the thiol-GP gel. At least 3 cycles of adsorption/elution could be obtained without decreasing the adsorption efficiency drastically. The adsorbed gold on the thiol-GP was able to be eluted effectively by using the mixture solution of 0.1 M thiourea and 0.1 M hydrochloric acid, and finally the solid gold could be recovered by sodium borohydride through a reduction process. This study demonstrated a green, environmentally friendly, low-cost, and efficient method for selective recovery of gold from the dilute leach liquor (aqua regia) of waste circuit boards.

Eighteen structurally diversified sesquiterpenes isolated from Pogostemon cablin and their inhibitory effects on nitric oxide production.

Five new sesquiterpenes, namely, guaianes A-E (1-5), including one novel carbon skeleton guaiane-type sesquiterpene derivatives (1), together with thirteen known compounds (6-18), were isolated from the aerial parts of Pogostemon cablin (Blanco.) Benth. Their chemical structures were mainly established through the relative spectroscopic data, while the absolute configurations of compounds 1-5 were elucidated on the base of single-crystal X-ray diffraction analysis and electronic circular dichroism (ECD) calculations. All compounds were tested for their inhibiting effects on NO production in LPS-stimulated BV2 microglia cells as well as the cell viabilities. The results showed that compounds 2-16 and 18 possessed moderately anti-inflammatory activities at a concentration of 50 µM.

Structure features, selenylation modification, and improved anti-tumor activity of a polysaccharide from Eriobotrya japonica.

A homogeneous polysaccharide, EJP90-1, was isolated from the leaves of E. japonica by hot water extraction in this study. EJP90-1 (7702 Da) was a heteropolysaccharide mainly consisting of →5)-linked-α-L-Araf-(1→, →4)-linked-ß-D-Manp-(1→, →2,4)-linked-α-L-Rhap-(1→, →4)-linked-α-D-Xylp-(1→, →4)-linked-ß-D-Galp-(1→, →2)-linked-ß-D-Galp-(1→, →6)-linked-ß-D-Glcp-(1→, α-D-Glcp-(4→, and t-linked-α-L-Araf. EJP90-1 was found to show moderate anti-tumor activity at the cellular level. In order to improve the anti-tumor activity and the potential applications of EJP90-1, a typical sodium selenite-nitric acid (Na2SeO3-HNO3) modification on EJP90-1 was carried out. X-ray photoelectron spectroscopy (XPS) and energy dispersive spectrometer (EDS) analysis confirmed that Se was successfully introduced into the polymer chain of EJP90-1. The subsequent in vitro cytotoxicity evaluation showed the selenylation modification derivative (EJP90-1-Se) possessed significant antiproliferative activity against cancer cells (HepG2 and A549 cells) through inducing cell apoptosis. The anti-tumor activity of EJP90-1-Se was further confirmed by zebrafish models, which inhibited the proliferation and migration of HepG2 cells and the angiogenesis.

Selective uptake of thorium(IV) from nitric acid medium using two extraction chromatographic resins based on diglycolamide-calix[4]arenes: Application to thorium-uranyl separation in an actual sample.

Two novel extraction chromatography resins (ECRs) containing two diglycolamide (DGA) -functionalized calix[4]arenes with n-propyl and isopentyl substituents at the amide nitrogen atom, termed as ECR-1 and ECR-2, respectively, were evaluated for the uptake of Th(IV) from nitric acid feed solutions. While both the resins were having a quite high Th(IV) uptake ability (Kd >3000 at 3 M HNO3), the uptake was relatively lower with the resin containing the isopentyl DGA, which appeared magnified at lower nitric acid concentrations. Kinetic modeling of the sorption data suggested fitting to the pseudo-second order model pointing to a chemical reaction during the uptake of the metal ion. Sorption isotherm studies were carried out showing a good fitting to the Langmuir and D-R isotherm models, suggesting the uptake conforming to monolayer sorption and a chemisorption model. Glass columns with a bed volume of ca. 2.5 mL containing ca. 0.5 g lots of the ECRs were used for studies to assess the possibility of actual applications of the ECRs. Breakthrough profiles obtained with feed containing 0.7 g/L Th(NO3)3 solution resulted in breakthrough volumes of 8 and 5 mL, respectively, for the ECR-1 and ECR-2 resins. Near quantitative elution of the loaded metal ion was possible using a solution of oxalic acid and nitric acid. A method for the separation of Th-234 from natural uranium was demonstrated for the possible application of ECR-1.

Actinide ion uptake from acidic radioactive feeds using an extraction chromatographic resin containing a branched dialkyl amide.

A dialkyl amide with branched alkyl group, viz. N,N-di(2-ethylhexyl)-propionamide (D2EHPrA) was used as the organic extractant in an extraction chromatographic resin prepared for the first time and evaluated for the separation of uranium from acidic feeds. The distribution coefficient measurements, carried out at varying HNO3 concentrations, indicated an increase in the UO22+ ion sorption with increasing nitric acid concentration. The UO22+ ion sorption kinetics and sorption isotherms with this resin were investigated in details. The column studies indicated that 8.3 mg of uranium could be loaded on a 2.1 cm3 column bed volume containing 0.35 g resin. Batch distribution data for other actinides such as Np4+ and Pu4+ indicated that the resin can also be used for effective separation of these metal ions from acidic feeds. Though the resin showed effectiveness for Np and Pu, detailed investigations dealing with macro concentrations of metal ions (in gm quantities) were restricted to uranium only due to hazardous nature of plutonium and limited availability of neptunium. The encouraging results reported in this work is an indication of the possible application of this resin for the recovery or pre-concentration of UO22+, Np4+ and Pu4+ ions from large volumes of aqueous solutions of moderate acidity.

Synthesis of Se-polysaccharide mediated by selenium oxychloride: Structure features and antiproliferative activity.

Selenium oxychloride (SOC) was employed as a highly reactive selenide reagent to synthesize selenized Artemisia sphaerocephala polysaccharides (SeASP). Se content of SeASP was significantly increased (∼22,400 µg/g) as compared to HNO3/H2SeO3 selenylation method (1703 µg/g). Furthermore, selenized ASP was prepared by using microwave-assisted synthesis which obviously enhanced selenylation kinetics. FT-IR, Raman, XPS and NMR results exhibited seleno-group was substituted at C6 position in the form of selenite (Se4+). SEC-MALLS suggested SOC system could effectively avoid the degradation of polysaccharide chain. Meanwhile, MALLS calculation, MB spectrophotometric method and AFM observation showed SeASP appeared spherical and rod-shaped conformation after selenylation. Seleno-groups were more likely to affect the conformational transformation of polysaccharide chains. Moreover, SeASP could significantly enhance antiproliferative activity against three tumor cells, of which the IC50 value of HepG2 was calculated as 24.35 µg/mL. It was found that higher Se content could effectively improve the antitumor activities of Se-polysaccharides in vitro.

Aqua regia digestion cannot completely extract Hg from biochar: A synchrotron-based study.

Mercury (Hg) is commonly extracted from solid phase samples using aqua regia for total Hg (tHg) analysis. However, uncertainties exist regarding the complete extraction of Hg by aqua regia, especially from carbonaceous materials. To investigate whether aqua regia can completely extract Hg from biochars, batch-style experiments were carried out to evaluate extraction efficiency of aqua regia with respect to Hg-loaded biochar and to characterize the residual Hg speciation and spatial distribution. Different types of biochars (raw, FeCl3-modified, and FeSO4-modified, prepared at different temperatures) were reacted with Hg-spiked solution before the digestion experiments. Adsorption analyses indicate the biochars were successfully loaded with Hg and that the Hg content was higher in biochars pyrolyzed at higher temperature (900 versus 300 or 600 °C). The results of digestion experiments indicate Hg could not be completely extracted from the biochars tested, with a greater percentage of residual Hg in biochars pyrolyzed at 600 (60 ± 15%) and 900 (75 ± 22%) than 300 °C (7 ± 2%). Furthermore, the fraction of residual Hg in FeSO4-modified biochars after aqua regia digestion was significantly lower than in FeCl3-modified and unmodified biochars. Confocal micro-X-ray fluorescence imaging (CMXRFI) showed residual Hg in biochars is concentrated on surfaces prior to digestion, but more homogeneously distributed after digestion, which indicates Hg on biochar surface is more easily digested. Hg extended X-ray absorption fine structure (EXAFS) spectra modelling showed residual Hg in biochars mainly exists as Hg(II)-Cl. These results indicate extra caution should be paid for tHg determinations using aqua regia digestion method in soil (especially in forest), sediment, and peat samples containing black carbon, activated carbon, or biochar.

Room temperature solvent extraction for simple and fast determination of total concentration of Ca, Cu, Fe, Mg, Mn, and Zn in bee pollen by FAAS along with assessment of the bioaccessible fraction of these elements using in vitro gastrointestinal digestion.

BACKGROUND AND AIM: Bee pollen is recognized to be a source of different nutrients, including minerals. As a food supplement, its quality and safety due to concentrations of essential macro- and microelements, and harmful trace elements has to be verified. Fast and simple element analysis of bee-collected pollen can be regarded as an important part of its quality assurance and control. The present study aimed at developping a new method for determination of selected elements (Ca, Cu, Fe, Mg, Mn, Zn) of bee pollen based on solvent extraction and completely avoiding a high temperature treatment with concentrated reagents. In addition, in vitro gastrointestinal digestion was used to assess bioavailability of elements from this food supplement. METHODS: Bee pollen samples were dried and pulverized. Total concentrations of Ca, Cu, Fe, Mg, Mn, and Zn were determined by flame atomic absorption spectrometry (FAAS) in sample solutions obtained by wet digestion (WD) in concentrated HNO3 or alternatively by solvent extraction (SE) with diluted solutions of HNO3. Gastrointestinal digestion was mimicked using simulated solutions of gastric and intestinal juices followed by determination of Ca, Cu, Fe, Mg, Mn and Zn concentrations in the bioaccessible fraction by FAAS. RESULTS: A new simple and fast method for determination of total concentrations of Ca, Cu, Fe, Mg, Mn, and Zn in bee pollen was developed and validated. The method combined room temperature, two-hour SE with 0.5 mol L-1 HNO3 with FAAS measurements versus simple standard solutions. It provided precision within 1-5 % and trueness better than 8%, and was shown to be suitable for fast analysis of different polyfloral bee pollens. In vitro gastrointestinal digestion revealed that elements were well (70-85 % for Ca, Mg) and fairly (27-43 % for Cu, Fe, Mn, and Zn) bioaccessible from bee pollen. By pouring with water and swelling overnight, bioaccessibility of studied elements from such prepared bee pollen was increased on average by less than 15 % (Mn), 20 % (Ca, Cu, Fe, Zn) or 30 % (Mn). CONCLUSIONS: Avoiding long-lasting, high-temperature wet digestion with concentrated reagents, the proposed sample treatment along with FAAS provided precise and true results of total concentrations of Ca, Cu, Fe, Mg, Mn, and Zn in bee pollen. The method was simple and fast, and enabled to analyze a higher number of samples. Simulated gastrointestinal digestion of bee pollen have shown for the first time that Ca and Mg are the most bioaccessible from this bee product. Bioaccessibility of Cu, Fe, Mg, and Zn from bee pollen are close to or lower than 40 %.

Endothelial Nitric Oxide Mediates the Anti-Atherosclerotic Action of Torenia concolor Lindley var. Formosama Yamazaki.

Torenia concolor Lindley var. formosama Yamazaki ethanolic extract (TCEE) is reported to have anti-inflammatory and anti-obesity properties. However, the effects of TCEE and its underlying mechanisms in the activation of endothelial nitric oxide synthase (eNOS) have not yet been investigated. Increasing the endothelium-derived nitric oxide (NO) production has been known to be beneficial against the development of cardiovascular diseases. In this study, we investigated the effect of TCEE on eNOS activation and NO-related endothelial function and inflammation by using an in vitro system. In endothelial cells (ECs), TCEE increased NO production in a concentration-dependent manner without affecting the expression of eNOS. In addition, TCEE increased the phosphorylation of eNOS at serine 635 residue (Ser635) and Ser1179, Akt at Ser473, calmodulin kinase II (CaMKII) at threonine residue 286 (Thr286), and AMP-activated protein kinase (AMPK) at Thr172. Moreover, TCEE-induced NO production, and EC proliferation, migration, and tube formation were diminished by pretreatment with LY294002 (an Akt inhibitor), KN62 (a CaMKII inhibitor), and compound C (an AMPK inhibitor). Additionally, TCEE attenuated the tumor necrosis factor-α-induced inflammatory response as evidenced by the expression of adhesion molecules in ECs and monocyte adhesion onto ECs. These inflammatory effects of TCEE were abolished by L-NG-nitroarginine methyl ester (an NOS inhibitor). Moreover, chronic treatment with TCEE attenuated hyperlipidemia, systemic and aortic inflammatory response, and the atherosclerotic lesions in apolipoprotein E-deficient mice. Collectively, our findings suggest that TCEE may confer protection from atherosclerosis by preventing endothelial dysfunction.

Harpagophytum procumbens Extract Ameliorates Allodynia and Modulates Oxidative and Antioxidant Stress Pathways in a Rat Model of Spinal Cord Injury.

Spinal cord injury (SCI) is a deliberating disorder with impairments in locomotor deficits and incapacitating sensory abnormalities. Harpagophytum procumbens (Hp) is a botanical widely used for treating inflammation and pain related to various inflammatory and musculoskeletal conditions. Using a modified rodent contusion model of SCI, we explored the effects of this botanical on locomotor function and responses to mechanical stimuli, and examined possible neurochemical changes associated with SCI-induced allodynia. Following spinal cord contusion at T10 level, Hp (300 mg/kg, p.o.) or vehicle (water) was administered daily starting 24 h post-surgery, and behavioral measurements made every-other day until sacrifice (Day 21). Hp treatment markedly ameliorated the contusion-induced decrease in locomotor function and increased sensitivity to mechanical stimuli. Determination of Iba1 expression in spinal cord tissues indicated microglial infiltration starting 3 days post-injury. SCI results in increased levels of 4-hydroxynonenal, an oxidative stress product and proalgesic, which was diminished at 7 days by treatment with Hp. SCI also enhanced antioxidant heme oxygenase-1 (HO-1) expression. Concurrent studies of cultured murine BV-2 microglial cells revealed that Hp suppressed oxidative/nitrosative stress and inflammatory responses, including production of nitric oxide and reactive oxygen species, phosphorylation of cytosolic phospholipases A2, and upregulation of the antioxidative stress pathway involving the nuclear factor erythroid 2-related factor 2 and HO-1. These results support the use of Hp for management of allodynia by providing resilience against the neuroinflammation and pain associated with SCI and other neuropathological conditions.

Crude Oil Sensing using Carbon Nano Structures Synthetized from Phoenix Dactylifera L. Cellulose.

This study reports on the crude oil-sensing using carbon nano structures (CNSs). A mixture of CNSs was obtained by a simple method of preparation using palm cellulose ash and nitric acid as precursors, the powder was characterized by x-ray diffraction and infrared spectroscopy. The optical density of crude oil from Rhoud El-Baguel area (Southeast of Algeria) studied using UV-Vis spectroscopy, before and after adding an amount of CNSs powder to view the CNSs crude oil sensing and therefore a new method to determine the quality of crude oils and the comparison between them. Results show that CNSs prepared from palm cellulose ash have a good crystallinity and it is formed mainly from carbon nano dots (CNDs) with 4.32 Å in layers spacing and 7.4 Å in crystallite size, indicate that CNSs can be used as an excellent crude oil sensor.

Physicochemical properties and bioactivities of original and Se-enriched polysaccharides with different molecular weights extracted from Pleurotus ostreatus.

Three polysaccharides (WZP1, WZP2, WZP3) and their Se-enriched products (SeWZP1, SeWZP2 and SeWZP3) were obtained from Pleurotus ostreatus using a simple, rapid method and HNO3-Na2SeO3 method, respectively. The molecular weight distribution profiles of all samples except SeWZP2 showed double peaks. The average molecular weights (Mw) of WZP1-3 were 48.6 kDa, 20.2 kDa and 11.8 kDa, respectively, and of SeWZP1-3 were 19.6 kDa, 37.7 kDa, 14.5 kDa, respectively. The complexity of monosaccharide composition of WZP1-3 was inversely proportional to the ethanol concentration used in the ethanol precipitation process. Additionally, the results of biological activity tests indicated that α-glucosidase inhibitory activity of WZP1-3 was related to the molecular weight and the monosaccharide composition complexity. The selenized modification can improve the α-glucosidase-inhibiting, hydroxyl radical-scavenging activity of P. ostreatus polysaccharides. Therefore, by improving their bioactivities by selenization, the polysaccharides of P. ostreatus could be utilized as a natural health food supplement.

Microwave-assisted digestion using dilute nitric acid solution and investigation of calibration strategies for determination of As, Cd, Hg and Pb in dietary supplements using ICP-MS.

This study proposes an analytical procedure for microwave-assisted sample preparation of dietary supplements for athletes using dilute nitric acid solution followed by determination of elemental impurities (As, Cd, Hg and Pb) by inductively coupled plasma mass spectrometry (ICP-MS) according to the United States Pharmacopeia Chapters 2232 and 233. Calibration strategies as internal standardization (IS), multi-isotope calibration (MICal), and one-point standard addition (OP SA) were applied for correction of matrix effects. The optimization of the sample preparation procedure was performed using Doehlert experimental design based on overall desirability results (residual acidity, dissolved organic carbon and recoveries reached for certified reference material of Typical Diet) for each calibration method evaluated. Accuracy was also evaluated by recovery experiments according to the permissible daily exposure specific for each element and samples were spiked with element concentrations of 0.5J and 1.5J in order to check accuracies for As, Cd, Hg and Pb. Recoveries ranged from 82 to 120% using IS, 90 to 125% using MICal, 88 to 120% using OP SA and the repeatability was demonstrated by a precision lower than 10% RSD. Ten samples of dietary sport supplements were analyzed using the three calibration methods evaluated and the concentrations of As, Cd and Pb determined in eight samples were lower than the limits established by the Chapter 2232.

Ecofriendly green conversion of potato peel wastes to high productivity bacterial cellulose.

Potato peel waste (PPW) is employed as the first report on bacterial cellulose (BC) production by Gluconacetobacter xylinus. Scharification of PPW was performed by 2 M different mineral acids individually. The suitable pre-treatment conditions were determined by reducing sugar release. Although all acid PPW-hydrolysates culture media are studied to produce BCs. Nitric acid hydrolysate gives the high productivity value The influence of nitric acid PPW-hydrolysate culture condition parameters were applied throughout the Taguchi method and the optimum conditions for the highest BC yield (4.7 g/L) was observed after 6 days at 35 °C, pH 9, medium volume 55 ml and with 8% inoculum size. The instrumental analysis of PPW-BC, included FT-IR, Particle size distribution, BET, DSC, XRD and SEM are cleared that the PPW-BC recorded high crystalliny82.5%, excellent PDI. In general, this study revealed that nitric acid PPW-hydrolysate could be used as cost effective alternative medium for production of BC with sustainable processes that can overcome the environmental pollution.

Phenolic compounds from the aerial parts of Clematis viticella L. and their in vitro anti-inflammatory activities.

Phytochemical investigations on the EtOH extract of Clematis viticella led to the isolation of six flavonoid glycosides, isoorientin (1), isoorientin 3'-O-methyl ether (2), quercetin 7-O-α-L-rhamnopyranoside (3), quercetin 3,7-di-O-α-L-rhamnopyranoside (4), manghaslin (5) and chrysoeriol 7-O-ß-D-glucopyranoside (6), one phenylethanol derivative, hydroxytyrosol (7), along with three phenolic acids, caffeic acid (8), (E)-p-coumaric acid (9) and p-hydroxybenzoic acid (10). The structures of the isolates were elucidated on the basis of NMR and HR-MS data. All compounds were isolated from C. viticella for the first time. Compounds 7 and 8 showed significant anti-inflammatory activity at 100 µM by reducing the release of NO in LPS-stimulated macrophages comparable to positive control indomethacin. Compounds 3 and 7 exhibited anti-inflammatory activity through lowering the levels of TNF-α while 1, 3 and 5 decreased the levels of neopterin better than the positive controls.

Microwave-assisted digestion using diluted HNO3 and H2O2 for macro and microelements determination in guarana samples by ICP OES.

A microwave-assisted digestion procedure using diluted HNO3 and H2O2 was developed for multi-element determination in guarana samples by ICP OES. Optimization step was performed employing a mixture design with pseudocomponents using HNO3, H2O2 and H2O. The analytical signal of each element, residual acidity and residual carbon content were optimized simultaneously using the desirability function. The best condition for digestion of a 250 mg sample mass resulted from a mixture constituted by 1.0 mL of HNO3, 3.0 mL of H2O2 and 6.0 mL of H2O. This condition allowed final digests with residual acidity and residual carbon content of 0.4 mol L-1 and 6.5%, respectively. The method was validated and applied for the determination of K, Ca, Mg, S, P, Cu, Fe, Mn and Zn in 72 guarana seed samples from Bahia state. This work presents unpublished results about the mineral composition of guarana seed samples produced in Bahia state, Brazil.