The combined effect of coating treatments to nisin, nano-silica, and chitosan on oxidation processes of stored button mushrooms at 4 °C

Agaricus bisporus is an edible fungus with a limited shelf life due to high moisture loss, browning, respiration, self-dissolve, lack of physical protection, rotting, and microbial attack. Mushrooms have been coated with nisin, nano-silica, and chitosan films in order to extend the shelf life, preserve quality and oxidation activities. The results showed that treating the mushrooms with chitosan and nano-silica (CH-AN-SILICA) increased superoxide dismutase activity (SOD—6.53 U kg−1), total phenolic content (TPC—0.39 g kg−1), and malondialdehyde content (MDA—1.63 µmol kg−1). CH-AN-SILICA treatment exhibited the highest scavenging against 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals. While, CH-AN-SILICA with the addition of nisin as an antimicrobial agent preserved almost the reactive oxygen species such as hydroxyl radicals (OH—0.33 µmol g−1), superoxide anion (O2•−—0.271 mmol s−1 kg−1), and hydrogen peroxide (H2O2—21.54 µmol g−1). Besides, both CH-AN-SILICA and CH-AN-SILICA/N enhanced the catalase (CAT) activity and reduced the respiration rate. The results indicated that the combination of nisin, nano-silica, and chitosan coating films was effective in providing a longer storage life with acceptable quality in mushrooms.

Statistical Approaching for Superhydrophobic Coating Preparation using Silica Derived from Geothermal Solid Waste

Material quality can be affected by humidity resulting in short durability. Many observations have been conducted to endure the durability of material, such as coating methods. However, recent methods are unaffordable. Therefore, this paper observes efficient and effective method to prepare superhydrophobic silica coatings derived from geothermal waste. The method was conducted by spraying. The objective of this paper is to observe optimum condition by using variables of silica concentration, TMCS (trimethylsilyl chloride) concentration, solvents and materials confirmed by contact angle of material based on statistical analysis. The study consisted of silica treatment for purification and preparation of superhydrophobic silica coatings. The study was carried out in factorial design of 81 experiments with one-time replication through Design Expert software (version 8.0.6). Based on previous research, the experiment was obtained optimum condition at 5.5 %w/v, 13 %v/v, isooctane, zinc coated for silica concentration, TMCS concentration, solvent and material, respectively, releasing contact angle by instrumentation of 180°. By ANOVA analysis, it was also complied the optimum condition of the superhydrophobic coating solution preparation achieved the same condition with experimental data releasing contact angle of 179.69°.

Silica treatment technologies in reverse osmosis for industrial desalination: A review

Reverse osmosis (RO) is the main process of current industrial desalination, and its performance is affected by the quality of water source. Natural water contains a certain level of silica, which is originated from metal silicate in the earth crust. Due to its complexity, silica fouling is difficult to control, which often causes less efficient design of RO system for safe operation. In the present work, we review the current state of silica treatment technology in RO desalination. Silica chemistry is investigated in standpoint of the scale formation mechanism among multiple forms of silica species and its synergistic interaction with other foulants such as organic matter. Then, pretreatment methods to remove silica in the RO feed water are outlined. They include softening/coagulation, seed precipitation/aggregation, tight ultrafiltration, ion exchange, adsorbents media, and electro coagulation. We finally highlight the mitigation of RO fouling under silica rich conditions, whose concept can be implemented in different ways of antiscalant dosing, high/low pH operation, and intermediate softening of the RO concentrate, respectively. This review will provide comprehensive information and insight about the optimal operation of industrial RO susceptible to silica fouling.

Comparative Aboveground Performance of Pressure-Treated Copper Azole with Alternative Wood Protection Systems under Subtropical Conditions

The performance of several wood surface treatments as well as a silica treatment claiming to provide protection against fungal decay and termite attack in aboveground applications were examined in termite, ground proximity, and sandwich tests at a subtropical site near Hilo, Hawaii. In general, the surface treatments performed similarly to untreated controls and provided little or no protection against fungal or insect attack. The silicate treatment provided some termite and decay protection, but fungal decay resulted in rapid declines in condition after 50 to 54 months of exposure. Copper azole–treated lumber provided the best performance against both termites and fungal attack, illustrating the benefits of pressure treatment over surface treatments in high-decay-hazard environments. These results also illustrate the importance of rigorous testing and standardization protocols for any product that makes durability claims before it enters the market to ensure that it will perform as expected.