A green sulfur bacterium from epsomitic Hot Lake, Washington, USA.

Hot Lake is a small heliothermal and hypersaline lake in far north-central Washington State (USA) and is limnologically unusual because MgSO4 rather than NaCl is the dominant salt. In late summer, the Hot Lake metalimnion becomes distinctly green from blooms of planktonic phototrophs. In a study undertaken over 60 years ago, these blooms were predicted to include green sulfur bacteria, but no cultures were obtained. We sampled Hot Lake and established enrichment cultures for phototrophic sulfur bacteria in MgSO4-rich sulfidic media. Most enrichments turned green or red within 2 weeks, and from green-colored enrichments, pure cultures of a lobed green sulfur bacterium (phylum Chlorobi) were isolated. Phylogenetic analyses showed the organism to be a species of the prosthecate green sulfur bacterium Prosthecochloris. Cultures of this Hot Lake phototroph were halophilic and tolerated high levels of sulfide and MgSO4. In addition, unlike all recognized species of Prosthecochloris, the Hot Lake isolates grew at temperatures up to 45 °C, indicating an adaptation to the warm summer temperatures of the lake. Photoautotrophy by Hot Lake green sulfur bacteria may contribute dissolved organic matter to anoxic zones of the lake, and their diazotrophic capacity may provide a key source of bioavailable nitrogen, as well.

Magnocaine: Physical Compatibility and Chemical Stability of Magnesium Sulphate and Lidocaine Hydrochloride in Prefilled Syringes.

OBJECTIVE: To evaluate the physical compatibility and chemical stability of mixtures of magnesium sulphate and lidocaine in order to determine the feasibility of manufacturing a prefilled syringe combining these two drugs for use as an intramuscular (IM) loading dose for eclampsia prevention and/or treatment. This ready-to-use mixture will provide a more tolerable and accessible route of administration appropriate for widespread use. METHODS: Physical compatibility (pH, colour, and formation of precipitate) and chemical stability (maintaining > 90% of initial concentrations) of mixtures of MgSO4, using both commercially available MgSO4 (50%) and MgSO4 reconstituted from salt (61%), with lidocaine hydrochloride (2%) were evaluated every 14 days over six months. The concentration of lidocaine was determined by a stability indicating high performance liquid chromatographic method, while the concentration of magnesium was determined by an automated chemistry analyzer. RESULTS: No changes in pH, color or precipitates were observed for up to 6 months. The 95% confidence interval of the slope of the curve relating concentration to time, determined by linear regression, indicated that only the admixtures of commercially-available magnesium sulfate and lidocaine as well as the 61% magnesium sulfate solution (reconstituted from salt) maintained at least 90% of the initial concentration of both drugs at 25°C and 40°C at 6 months. CONCLUSIONS: Commercially available MgSO4 and lidocaine hydrochloride, when combined, are stable in a pre-filled syringe for at least six months in high heat and humidity conditions. This finding represents the first step in improving the administration of magnesium sulphate in the treatment and prevention of eclampsia in under-resourced settings.

Absence seizure associated with coloprep consumption in colonoscopy / Convulsão de ausência com o uso de Coloprep em colonoscopia

Coloprep is a bowel preparatory solution given before endoscopic procedures to get a unobscured internal vision. It has among its constituent's sodium sulphate, potassium sulphate and magnesium sulphate which produce an osmotic effect in the bowel. However, the use of such agents in hyponatremic and patients predisposed to seizures can have adverse ramifications. The current case outlines manifestation of absence seizure in a 52-year-old male patient who was administered Coloprep for colonoscopy. There was absence of other predisposing factors and the symptoms were ameliorated using timely identification and rectification of the underlying derangements.

Coloprep é uma solução preparatória intestinal administrada antes de procedimentos endoscópicos, com o objetivo de se ter uma visão interna não obscurecida. Entre os constituintes de Coloprep, observa-se sulfato de sódio, sulfato de potássio e sulfato de magnésio, que provocam efeito osmótico no intestino. Mas o uso de tais agentes em pacientes hiponatrêmicos e com predisposição para convulsões pode ter ramificações adversas. O caso em tela delineia uma manifestação de convulsão de ausência em paciente do gênero masculino com 52 anos e que recebeu Coloprep para colonoscopia. Não havia outros fatores predisponentes e os sintomas melhoraram graças à oportuna identificação e correção dos transtornos subjacentes.

Scanning electron microscopy of hair treated in hard water.

BACKGROUND: Hardness of water is determined by the amount of calcium carbonate (CaCO3 ) and magnesium sulfate (MgSO4 ) dissolved in it. Hardness of water used for washing hair may damage the hair. OBJECTIVES: The objective of this study is to observe the surface changes due to hard water usage and compare the thickness of hair between hard and soft water treated samples. METHODS: Ten to 15 hair strands of length 15-20 cm, which were lost during combing, were obtained from 15 healthy female volunteers. Each hair sample was cut into two equal halves to obtain two sets per volunteer. Each hair sample was wrapped around a glass rod. One set of 15 samples was washed with hard water, and the other set was washed with distilled water for 10 minutes on alternate days and air-dried. This procedure was carried out for 30 days. The surface of hair treated in hard and soft water was examined under a scanning electron microscope. RESULTS: The CaCO3 and MgSO4 content of hard and distilled water samples were determined as 212.5 ppm of CaCO3 and 10 ppm of CaCO3 respectively. The mean calcium deposition in hard and distilled water treated hair was determined as 0.804% and 0.26%, respectively. The mean magnesium deposition in hard and distilled water treated hair was determined as 0.34% and 0.078%, respectively. The mean thickness of hair treated in hard water and distilled water were 72.78 and 78.14 µm, respectively. CONCLUSION: The surface of hard water treated hair has a ruffled appearance with higher mineral deposition and decreased thickness when compared with the surface of distilled water treated hair.

Formation and reduction of furan in a soy sauce model system.

The formation and reduction of furan using a soy sauce model system were investigated in the present study. The concentration of furan fermented up to 30 days increased by 211% after sterilization compared to without sterilization. Regarding fermentation temperature, furan level after 30 days' fermentation was the highest at 30°C (86.21 ng/mL). The furan levels in the soy sauce fermentation at 20°C and 40°C were reduced by 45% and 88%, respectively compared to 30°C fermentation. Five metal ions (iron sulfate, zinc sulfate, manganese sulfate, magnesium sulfate, and calcium sulfate), sodium sulfite, ascorbic acid, dibutyl hydroxyl toluene (BHT), and butylated hydroxyanisole (BHA) were added in a soy sauce model system. The addition of metal ions such as magnesium sulfate and calcium sulfate reduced the furan concentration significantly by 36-90% and 27-91%, respectively in comparison to furan level in the control sample (p<0.05). Iron sulfate and ascorbic acid increased the furan level at 30 days' fermentation in the soy sauce model system by 278% and 87%, respectively. In the case of the BHT and BHA, furan formation generally was reduced in the soy sauce model system by 84%, 56%, respectively.

Efficacy and safety of a magnesium sulfate-rich natural mineral water for patients with functional constipation.

BACKGROUND & AIMS: Little is known about the effects of natural mineral water on constipation in adults. We assessed the effect of a magnesium sulfate-rich natural mineral water (Hépar; Nestlé Waters, Issy-les-Moulineaux, France) on gastrointestinal transit in constipated women. METHODS: We performed a randomized, double-blind, placebo-controlled trial to evaluate the efficacy and safety of Hépar in outpatients with functional constipation (based on the Rome III criteria). The study included 244 female patients, age 18 to 60 years, identified by 62 general practitioners throughout France. After a washout period, subjects drank 1.5 L natural low-mineral water daily (control, n = 77), 0.5 L Hépar and 1 L natural low-mineral water daily (Hépar 0.5 group, n = 85), or 1 L Hépar and 0.5 L natural low-mineral water daily (Hépar 1 group, n = 82) for 4 weeks. We collected information on the number and types of stools, abdominal pain, rescue medications, adverse events, and volume of water consumed. RESULTS: We observed no significant effect at week 1. At week 2, constipation was reduced in 21.1% of patients in the control group, in 30.9% in the Hépar 0.5 group (P = .099 vs controls), and in 37.5% in the Hépar 1 group (P = .013 vs controls). The Hépar 1 group also had a decreased number of hard or lumpy stools (Bristol scale, P = .030 vs baseline) and a substantial decrease in the use of rescue medication (P = .034 vs controls). Patient responses correlated with magnesium sulfate concentrations. Safety was very good; there were no serious adverse events among patients who drank Hépar. CONCLUSIONS: In a controlled trial, daily consumption of 1 L Hépar reduced constipation and hard or lumpy stools in a greater percentage of women with functional constipation than natural low-mineral water, as early as the second week of treatment.

Source identification of sulphate forming salts on sandstones from monuments in Salamanca, Spain--a stable isotope approach.

BACKGROUND, AIM AND SCOPE: Salt efflorescences markedly contribute to the alteration and deterioration of building material, in this case the Villamayor Sandstone of the facades in the Old Town of Salamanca, Spain (United Nations Educational, Scientific and Cultural Organization world cultural heritage site). A better understanding of the mechanisms of salt formation and the involved elements would allow more precise measures in monument conservation. The magnesium which is required for the salt precipitation originates from selective processes of hydrolysis. The source of sulphate, however, is presently not as clear. Identifying the source of the sulphur was the main goal of this research. Isotope ratio measurement of delta(34)S and delta(18)O was used to clarify the origins of Mg sulphate salts. MATERIALS AND METHODS: A total of 56 Mg sulphate samples were collected in two different seasons (July and November 2005) from monuments of the Old Town of Salamanca. These sampled salt efflorescences were analysed for delta(34)S and delta(18)O by mass spectrometry. A 'dual-inlet' type by VG Isotech was used for delta(34)S and continuous flow type Isoprime by GV Instruments for delta(18)O. Samples were measured in triplicates and standard material was analysed for quality control. RESULTS: delta(34)S values range between 3.6 per thousand and 15.4 per thousand with a median value of 10.2 per thousand for the July samples and of 10.1 per thousand for November samples. The results of the sulphur ratios hint towards a bimodal distribution (with modes at delta(34)S = 6 per thousand and 12 per thousand) for winter samples, which is less obvious during summer. delta(18)O values range from 7.1 per thousand to 41.1 per thousand. However, most values range from 7.1 per thousand to 20.8 per thousand, whereas only few summer samples show outliers towards higher delta(18)O values. The median delta(18)O value for July samples is 15.5 per thousand and for November samples 14.6 per thousand. DISCUSSION: The isotopic ratios of the analysed sulphate samples were compared with values of possible source materials. Sulphur sources in the case of Salamanca are barites from the Villamayor Sandstone itself, sea spray, sulphides from regional rocks, biogenic sulphur (soil, avian excreta), as well as sulphur from anthropogenic sources such as building materials (especially mortar) or traffic exhaust. Salamanca is a representative site for non-industrial cities with no heavy industry and thus, there are no significant SO(2) emissions from industry. CONCLUSIONS: Based on the measured isotopic ratios, it was ascertained that more than one sole sulphur source is present. However, based on additional information about the source material and possible transport ways, some sources could be excluded whereas others only played a minor role. Finally, there is strong indication that the main sulphur source is atmospheric pollution and the exhaust emissions from vehicles in particular, while mortar as building material also contributes to a minor extent. The delta(18)O values support this hypothesis. Moreover, the reported delta(18)O values are a strong indicator of the secondary nature of the Mg sulphates. Isotope ratio measurement and especially the combined use of delta(34)S and delta(18)O values have proven to be a good instrument in clarifying the origin of salt efflorescences on buildings. RECOMMENDATIONS AND PERSPECTIVES: Further studies should investigate more closely the isotopic composition of atmospheric aerosols in Salamanca in order to get a more detailed knowledge about the main sulphur sources, as well as to quantify the relation between the isotopic values and the amount and mineralogical form of the salts.

Determination of pesticide residues in foods by acetonitrile extraction and partitioning with magnesium sulfate: collaborative study.

A collaborative study was conducted to determine multiple pesticide residues in fruits and vegetables using a quick, simple, inexpensive, and effective sample preparation method followed by concurrent analysis with gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/ tandem mass spectrometry (LC/MS/MS). For short, the method is known as QuEChERS, which stands for quick, easy, cheap, effective, rugged, and safe. Twenty representative pesticides were fortified in 3 matrixes (grapes, lettuces, and oranges) at 3 duplicate levels unknown to the collaborators ranging from 10 to 1000 ng/g. Additionally, 8 incurred pesticide residues were determined. Thirteen laboratories from 7 countries provided results in the study, and a variety of different instruments were used by collaborators. The QuEChERS procedure simply entails 3 main steps: (1) a 15 g homogenized sample is weighed into a 50 mL centrifuge tube to which 15 mL acetonitrile containing 1% HOAc is added along with 6 g MgSO4 and 1.5 g NaOAc, and the tube is shaken and centrifuged; (2) a portion of the extract is mixed with 3 + 1 (w/w) MgSO4-primary secondary amine sorbent (200 mg/mL extract) and centrifuged; and (3) the final extract is analyzed by GC/MS and LC/MS/MS. To detect residues <10 ng/g in GC/MS, large-volume injection of 8 microL is typically needed, or the extract can be concentrated to 4 g/mL in toluene, in which case 2 microL splitless injection is used. In the study, the averaged results for data from 7-13 laboratories (not using internal standardization) for the 18 blind duplicates at the 9 spiking levels in the 3 matrixes are as follows [%recovery and reproducibility relative standard deviation (RSD(R), %)]: atrazine, 92 (18); azoxystrobin, 93 (15); bifenthrin, 90 (16); carbaryl, 96 (20); chlorothalonil, 70 (34); chlorpyrifos, 89 (25); cyprodinil, 89 (19); o,p'-DDD, 89 (18); dichlorvos, 82 (21); endosulfan sulfate, 80 (27); imazalil, 77 (33); imidacloprid, 96 (16); linuron, 89 (19); methamidophos, 87 (17); methomyl, 96 (17); procymidone, 91 (20); pymetrozine, 69 (19); tebuconazole, 89 (15); tolylfluanid (in grapes and oranges), 68 (33); and trifluralin, 85 (20). For incurred pesticides, kresoxim-methyl (9.2 +/- 3.2 ng/g) and cyprodinil (112 +/- 18) were found in the grapes; permethrins (112 +/- 41), lamda-cyhalothrin (58 +/- 11), and imidacloprid (12 +/- 2) were determined in the lettuces; and ethion (198 +/- 36), thiabendazole (53 +/- 8), and imazalil (13 +/- 4) were determined in the oranges. Chlorpyrifosmethyl (200 ng/g) was used as a quality control standard added during sample homogenization and yielded 86% recovery and 19% RSD(R). Intralaboratory repeatabilities for the method averaged 9.8% RSD for all analytes. The results demonstrate that the method is fit-for-purpose to monitor many pesticide residues in fruits and vegetables, and the Study Director recommends that it be adopted Official First Action.

Crystal growth and vibrational spectroscopic studies of the semiorganic non-linear optical crystal--bisthiourea magnesium sulphate.

The semiorganic non-linear optical crystal bisthiourea magnesium sulphate (BTMS) was grown by slow evaporation technique using water as solvent. Vibrational spectra were recorded to determine the symmetries of molecular vibrations. The observed Raman and infrared bands were also assigned and discussed. The optical transmission spectral study was carried out to test the transmitting ability of the crystal in the visible range. The second harmonic generation test of BTMS revealed the non-linear nature of the crystal. The TGA/DTA curve was also recorded for the experimental crystal.

Effect of salt nutrients on mannitol production by Lactobacillus intermedius NRRL B-3693.

The effects of four salt nutrients (ammonium citrate, sodium phosphate, magnesium sulfate, and manganese sulfate) on the production of mannitol by Lactobacillus intermedius NRRL B-3693 in a simplified medium containing 300 g fructose, 5 g soy peptone, and 50 g corn steep liquor per liter in pH-controlled fermentation at 5.0 at 37 degrees C were evaluated using a fractional factorial design. Only manganese sulfate was found to be essential for mannitol production. Added manganese sulfate concentration of 0.033 g/l was found to support maximum production. The bacterium produced 200.6 +/- 0.2 g mannitol, 61.9 +/- 0.1 g lactic acid, and 40.4 +/- 0.3 g acetic acid from 300 g fructose per liter in 67 h.

Pesticides and other chemical contaminants.

A new topic needs to be added to this refereeship this year. This topic is Ultra-trace method for pesticides in bottled soft drinks. The Study Director is Paul Milne. The topic Dioxins by GC/MS remains vacant.

Magnesium sulphate salts and the history of water on Mars.

Recent reports of approximately 30 wt% of sulphate within saline sediments on Mars--probably occurring in hydrated form--suggest a role for sulphates in accounting for equatorial H2O observed in a global survey by the Odyssey spacecraft. Among salt hydrates likely to be present, those of the MgSO4*nH2O series have many hydration states. Here we report the exposure of several of these phases to varied temperature, pressure and humidity to constrain their possible H2O contents under martian surface conditions. We found that crystalline structure and H2O content are dependent on temperature-pressure history, that an amorphous hydrated phase with slow dehydration kinetics forms at <1% relative humidity, and that equilibrium calculations may not reflect the true H2O-bearing potential of martian soils. Mg sulphate salts can retain sufficient H2O to explain a portion of the Odyssey observations. Because phases in the MgSO4*nH2O system are sensitive to temperature and humidity, they can reveal much about the history of water on Mars. However, their ease of transformation implies that salt hydrates collected on Mars will not be returned to Earth unmodified, and that accurate in situ analysis is imperative.

Hydrated salt minerals on Ganymede's surface: evidence of an ocean below.

Reflectance spectra from Galileo's near-infrared mapping spectrometer (NIMS) suggests that the surface of Ganymede, the largest satellite of Jupiter, contains hydrated materials. These materials are interpreted to be similar to those found on Europa, that is, mostly frozen magnesium sulfate brines that are derived from a subsurface briny layer of fluid.

Biological effects of inhaled magnesium sulphate whiskers in rats.

Male Wistar rats were exposed to two types of magnesium sulphate whiskers by inhalation for six hours a day, five days a week, for four weeks (sub-chronic study), or for one year (chronic study) to clarify the biological effects of the whiskers. There were few whiskers detected in the rat lungs even at one day after the exposure, suggesting that they are dissolved and eliminated rapidly from the lungs. To measure the clearance rate of the whiskers from the lungs, an intratracheal instillation was performed in golden hamsters. The half life of the whiskers in the lung was determined as 17.6 minutes by temporally measuring the magnesium concentration up to 80 minutes after the instillation. A histopathological examination indicated a frequent occurrence of adenoma and carcinoma in the year after chronic exposure, but it was not significantly different between exposed and control rats.

The evaporation path of seawater and the coprecipitation of Br- and K+ with halite.

Brines and salt were sampled at the Morton Bahamas solar salt production facility on Great Inagua Island in the Bahamas. The brines were analyzed by ion chromatography to define more precisely than heretofore the evaporation path of seawater to the end of the halite facies. At Inagua, calcium carbonate begins to precipitate at a brine concentration factor of 1.8 times that of seawater. Gypsum begins to precipitate at a brine concentration of 3.8 times seawater, and halite at a concentration factor of 10.6. Three of the most concentrated brines from Inagua (40 times seawater) were evaporated further in the laboratory. Magnesium sulfate first precipitated at brine concentrations about 70 times those of seawater, and potassium-bearing phases began to precipitate for these brines at concentrations greater than 90 times those of seawater. The distribution of coefficients of Br- and K+ between brines and halite were determined by combining analytical data for the Inagua brines with measurements of the Br- and K+ content of halites from Inagua and of halite which had precipitated from Inagua brines during storage. The observed average value of DBr- is 0.032, in good agreement with some of the previous measurements. The measured values of DK+ are highly variable (0.001 to 0.021); DK+ for halite precipitated early in the halite facies is in the vicinity of 0.015.

The growth of Paracoccus halodenitrificans in a defined medium.

A synthetic medium, consisting of inorganic salts and any of a number of carbon sources, supported the aerobic growth of Paracoccus halodenitrificans when supplemented with thiamine. The same medium plus an appropriate nitrogenous oxide supported anaerobic growth when additionally supplemented with methionine. The observation that vitamin B12 or betaine replaced methionine suggested that P. halodenitrificans had a defect in the cobalamin-dependent pathway for methionine biosynthesis, as well as the inability to synthesize betaine when growing anaerobically.