Influence of Sulphate Nutrition on Growth Performance and Antioxidant Enzymes Activities of Spirulina platensis

The growth of Spirulina platensis is dependent on culture conditions. This study has established adequate conditions for the quality and quantity production of S. platensis. The effect of sulphate salts nutrition on growth performance and biochemical status of S. platensis was assessed in vitro. Prior to culture, the Paracas strain of S. platensis from SAGRIC pond was analysed in different magnesium sulphate (MgSO4; 0.08, 0.16, 0.32, 0.64 and 1.28 g/L), potassium sulphate (K2SO4; 0.08, 0.16, 0.32, 0.64 and 1.28 g/L) and MgSO4/K2SO4 (0.16/0.00, 0.08/0.08, 0.04/0.12, 0.02/0.14 and 0.01/0.15 g/L) concentrations. Culture media pH, total dissolved solids (TDS) and conductivity rate were monitored. Microscopic analysis revealed sulphate salt concentrations influenced the number of whorls and filaments of S. platensis. K2SO4 (1.28 g/L) produced the highest number of whorls and filaments. Moreover, pH level fluctuated by sulphate treatments. K2SO4 (1.28 g/L) had a pH level of 8.77±0.01 (day 5 of culture incubation). TDS and conductivity rate, protein and cysteine contents increased with culture age and K2SO4 concentration in a culture medium. Conversely, negative correlations between protein and cysteine contents were observed, and sugar content decreased. Sulphate salt type and concentrations affected polyphenol oxidase (PPO) and peroxidase (POD) activities. MgSO4/K2SO4 (0.02/0.14 g/L) displayed the best PPO and POD activities. Both enzymes appeared to be negatively correlated to the decreasing sugar content. These results indicate growth performances and biochemical status of S. platensis are significantly improved with the adequate supplementation of sulphate salts (MgSO4 and K2SO4) in culture media.

The influence of light and relative humidity on the formation of epsomite in cadmium yellow and French ultramarine modern oil paints

The effect of relative humidity (RH) and light on the development of epsomite (MgSO4·7H2O) in Winsor & Newton cadmium yellow (CY) and French ultramarine (FU) artists’ oil colour paints was investigated. Tube paint samples were aged for 12 weeks at either 50% or 75% RH, under ambient light (200 ± 1 lx), elevated light (11,807 ± 328 lx), and near-dark conditions. Aged paint samples were characterised using light microscopy (LM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Results indicated that ageing at 75% RH in elevated light conditions, promoted the formation of hydrated magnesium sulphate (MgSO4·6–7H2O) crystals on the surface of both paints. The formation of sodium sulphate (Na2SO4) as a degradation product of French ultramarine oil paints after ageing at 75% RH in elevated light conditions is described. The formation of magnesium sulphate crystals in the absence of elevated SO2 is a new finding. For both cadmium yellow and French ultramarine oil paints, the pigments present are a likely source of sulphur, enabling the formation of sulphate salts, i.e., cadmium sulphide (CdS) yellow, and the sulphur radical anions (S3−) present in ultramarine pigment. Sulphur-containing impurities arising from pigment manufacture are an additional possibility. It was previously theorised that epsomite formation in water-sensitive twentieth century oil paintings resulted from exposure to the elevated atmospheric sulphur dioxide (SO2) levels of the 1950s–1970s. This study demonstrates that hydromagnesite-containing cadmium yellow and French ultramarine oil paints of any period may be vulnerable to water-soluble sulphate salts formation and that this process is promoted by exposure to light and high (75%) RH environments. The formation of sulphate salts as a degradation product is known to contribute toward the development of water sensitivity of modern oil paintings which can pose significant challenges to conservation. Therefore this study highlights the importance of minimising exposure to light and raised relative humidity for paintings containing such CY and FU oil paint passages, to help slow down these types of degradation phenomena which have implications for preservation.

Evaluation of sodium salt scaling in black liquor evaporators using existing process data

Scaling caused by sodium carbonate and sodium sulphate salts is a common problem during black liquor evaporation and mills currently have no proper tools to monitor or follow it up. The method proposed enables automatic evaluation of scaling rates and behaviours, together with washing performance, by using measurements that are already available at most mills, such as the boiling point elevation and the overall heat transfer coefficient. The method identified the scaling correctly in most cases, normally >90 %, although fast and sudden scaling proved to be challenging; its performance was also dependent on the quality of the data used. Historical data from three mills was evaluated and it was found that the scaling rate generally increased at higher concentrations of black liquor: one of the mills had almost no scaling below 70 % dry solids content. Another mill, however, deviated from this trend and had significant problems with fast and sudden scaling in one effect at around 60 % dry solids content. The correlation of process parameters revealed that this scaling was triggered, to a large extent, by the absence of tall oil brine, which is a side stream from the production of tall oil that is normally fed to the evaporators.

Biosynthesis, purification, characterization and immobilization of laccase from Lithothelium sp.

Novel fungal laccase isoenzymes (namely L95-1 and L95-2) produced by the Ascomycete Lithothelium sp. isolated from the forest soil were purified. However, only one of them was characterized, because the other isoenzyme lost its activity during purification. Extracellular L95-1 laccase was purified 30-fold using ion-exchange and hydrophobic interaction chromatography, with an overall yield of 88%. The molecular mass of purified L95-1 was estimated to be 85 kDa by SDS-PAGE analysis. L95-1 laccase was stable at temperature 4–22°C and pH 6.0–6.5. The substrate specificity of L95-1 laccase was examined with various compounds. Determined affinity constants (KM) varied in a wide range of 3.7–2020.0 µM, whereas catalytic efficiency constants (kcat/KM) covered a range of 0.008–1.9 µM–1 s–1. The optimum pH for most substrates varied in a range from pH 5.0 to 6.0. Sodium azide and fluoride strongly inhibited L95-1 activity, whereas sulphate salts inhibited weakly. The laccase was immobilized on the Fe3O4 nanoparticles and characterized. Residual activity remained at 20% after ten cycles of ABTS oxidation reaction. The immobilized laccase showed higher tolerance to various metal salts. The properties of L95-1 laccase make it potentially useful in the biotechnological applications.

Uptake of Chromium by Portulaca Oleracea from Soil: Effects of Organic Content, pH, and Sulphate Concentration

Phytoextraction is an effective and environment-friendly approach for remediation of soil polluted with toxic metals. Portulaca oleracea is a potential hyperaccumulator of Cr(VI) from polluted soil. In this study, the effect of soil organic content, pH, and sulphate concentration on phytoextraction of Cr(VI) using Portulaca oleracea was investigated. Seedlings of Portulaca oleracea were grown in soils with (i) three organic content compositions, (ii) six levels of pH, and (iii) six concentrations of sulphate salts; all were irrigated with Cr(VI) solutions at 200 ppm concentration. Chromium concentration in different tissues of plants was monitored under the variant conditions. Results indicated that the uptake of Cr(VI) by Portulaca oleracea is favoured at (i) low organic content soil (0.42%), (ii) slightly alkaline pH range (∼8), and (iii) with sulphate concentration in the range of 300–600 ppm.

Selection of Method of Chemical Analysis in Measuring the Salinity of Mineral Materials

The article deals with the issue of salt content in brick buildings, which plays an important role in the assessment of the technical condition, in particular of historic buildings. A question has been asked about the selection of the best research method to determine the salinity of mineral materials. To obtain the answer, the authors conducted some tests on ceramic bricks salted with seven types of salt solutions. Research methods such as: spectrophotometry (UV), ion chromatography (High Performance Liquid Chromatography (HPLC)), X-Ray Fluorescence Spectrometry (XRF) and Energy-Dispersive X-Ray Spectroscopy (EDS) were compared. The above methods belong to two groups: the first is based on aqueous extracts and allows the determination of water-soluble salts, and the second concerns testing directly on the sample so that insoluble salts can also be determined. The results tests indicate that the methods based on solid phases (XRF and EDS) give higher salinity values than those based on aqueous extracts (HPLC and UV). The results were also analysed with regard to the type of salt. Larger differences are observed for sulphate salts while chloride salts are characterised by smaller differences. On this basis, it is concluded that the salt content of the material is best assessed using tests that make it possible to recognise the salt in question and its quantity.

Supramolecular organisation of sulphate salt hydrates exemplified with brucine sulphate

The frequency of hydrate formation among organic sulphate salts is unravelled. Interconversion of the hydrates of brucine sulphate occurs with small changes in the relative humidity.

Augmenting Cleansing Process for Reducing Occupational Hazards Experienced by Labours Handling Pyrotechnical Chemicals in Firecracker Units

The value of Human resource is considered to be very important in fire work industries. Nearly 90% of fire crackers are manufactured in Sivakasi, which is considered to be the hub of fireworks production in India. The manufacturing process, type of storage and handling of chemicals are some of the important factor which bears the responsibility of affecting the worker’s health. Firecrackers manufacturing involves mixing of various chemicals. Moreover, it leads to lot of health issue to the workers like respiratory disorders, skin problems, damage to kidney, mental impairment and eye irritation, also it can cause cancer. Out of these major problems, skin and respiratory issues are mainly caused due to the direct handling of chemicals without safety precautions. Chemicals such as Sulphur-di-oxide, copper nitrate and magnesium are highly used in manufacturing the crackers. In order to overcome these hazardous problems, we have planned to make a soap for the affected people through precipitation method, using organic solvent (ETHANOL) and with the mixture of alum and sodium lauryl sulphate salts. The main aim of doing this project is to give a product of low cost with longevity and with good quality, which provides ample protection through cleanliness to the people who work in fire cracker units