Papers by Keyword: Sodium Sulfite

Abstract: Gluten is a protein that gives a chewy characteristic to wheat flour-based foods. Gluten consists of glutenin and gliadin linked by disulfide bonds in which gliadin gives the viscosity and extensibility properties of gluten. Based on its properties, gliadin has great potential as a biomaterial and has been widely used in both the pharmaceutical and food industries. The separation between gliadin and glutenin generally uses alcohol such as 60-70% ethanol and 1-propanol. However, this method is inefficient and can cause environmental pollution. Another method is to add a food grade aqueous acidic medium where the separation occurs due to the difference in isoelectric point between gliadin and glutenin. Aim of the research to determine the effect of sodium sulfite with varying concentration on the separation of gliadin from gluten. In this study, gliadin was separated using 98% acetic acid, while sodium sulfite was used as a reducing agent to break the disulfide bond. To precipitate glutenin, the pH of the dispersion was adjusted to 4.4 using 5% ammonium hydroxide. The centrifugation was carried out at 8000 rpm to obtain the gliadin. The FT-IR spectrum showed that gliadin had absorption in the amide I band (C=O), namely α helix for the use of 0.1% and 0.15% of sodium sulfite and β sheet for 0.2% of sodium sulfite. The SDS-PAGE analysis on the use of all concentrations of sodium sulfite contained gliadin with a molecular weight of 25-40 kDa. After comparing it with marker proteins, it was estimated that it contains only α/β gliadin and γ- gliadin. The RP – HPLC chromatogram showed that the use of 0.1% and 0.2% sodium sulfite resulted in ω5 gliadin and ω 1,2 gliadin types, and at 0.15% sodium sulfite resulted in the most complete types, namely ω5 gliadin, ω1,2 gliadin and α /β gliadin, each containing glutamine, proline, phenylalanine, tyrosine and glycine. Overall, the use of 98% acetic acid at a certain pH with sodium sulfite as a reducing agent can separate gliadin from gluten. However, there was a change in the three-dimensional structure of gluten proteins so not all gliadin fractions can be identified completely.Keywords: 98% acetic acid; gliadin; isoelectric point; sodium sulfite

Abstract: In this study, a symmetric electrochemical capacitor has been fabricated by adopting the lithiated compound (LiFePO4)-activated carbon (AC) composite as the core electrode materials. The electrochemical performances of the prepared supercapacitor were studied using cyclic voltammetry (CV) in 1.0 M Na2SO3 solution. Experimental results reveal that the maximum specific capacitance of 112.41 F/g is obtained in 40 wt % LiFePO4 loading on AC electrode in comparison to that of pure AC electrode (76.24 F/g) in 1 M Na2SO3. The enhanced capacitive performance of the 40 wt % LiFeO4 –AC composite electrode is believed attributed to the contribution of synergistic effect of electric double layer capacitance (EDLC) on the surface of AC as well as pseudocapacitance via intercalation/extraction of Na+, SO32-and Li+ ions in LiFePO4 lattices. The composite electrodes can sustain a stable capacitive performance at least 1000 cycles with only ~5 % specific capacitance loss after 1000 cycles. Based on the findings above, 40 wt % LiFeO4 –AC composite electrodes which utilise low cost materials and environmental friendly electrolyte is worth being investigated in more details.

Abstract: This paper focuses on the effect by sodium sulfite on the enzyme activity and stabilization of rice bran. First, enzymes are studied by detecting the activity of lipase and peroxidase. Then the total antioxidant capacity is tested in order to clarify the effect of sodium sulfite on antioxidant substances. Finally, processed rice bran is storaged in constant temperature to observe the change of fatty acid and peroxide value. The optimal condition is 4% sodium sulfite for 150min. The results show that the sodium sulfite can reduce the enzyme activity to improve the stability of rice bran.

Abstract: The oxygen transfer process of starch wastewater in the shaking bioreactor was studied. A biological oxygen consumption system was simulated by the sodium sulfite solution. The effects of liquid volume ratio in different volume shake flasks, rotational speed and temperature on the volumetric oxygen transfer coefficient were investigated. The results show that the volumetric oxygen transfer coefficient increased with the increasing rotational speed and temperature, while decreased with the increasing volume of shaking flasks.

Abstract: We report the synthesis of soft magnetic Fe-Co nanobars by an improved polyol process using cetyltrimethylammonium bromide (CTAB) as stabilizer. The synthesized samples were studied by using Transmission Electron Microscopy. The Fe-Co nanoparticles were characterized by X-ray diffraction, UV-Vis spectroscopy, Fourier transform infrared spectroscopy and Vibrating Sample Magnetometer. The Fe-Co nanobars showed prominent UV-VIS absorption at 371 nm. This report discusses the effect of sodium sulfite and CTAB on the synthesis of Fe-Co nanoparticles.