RESUMEN
Green active film from chitosan (C) incorporated with spontaneous emulsified cinnamon oil nanoemulsion (CONE; droplet size of 79.27 nm and polydispersity index of 0.27) was developed. The obtained chitosan film containing CONE (C + CONE) had tensile elongation and light protective effect higher than C film due to the incorporation of bioactive compounds from cinnamon oil as proven by Fourier Transform Infrared Spectroscopy. The effect of C + CONE as active edible coating on the physical, chemical, and microbiological properties of dried shrimp was then investigated. The quality of samples coated with C + CONE (DS + C + CONE) was compared to those coated with C (DS + C) and without coating (DS). In this study, C + CONE could enhance astaxanthin content and reduce lipid oxidation in dried shrimp. During 6 weeks of storage, C + CONE was found to be an effective antimicrobial coating that significantly inhibited growth of bacteria, delayed lipid oxidation and retarded the production of volatile amines in dried shrimp. DS + C + CONE had lower malonaldehyde equivalents (0.52 mg/kg oil), trimethylamine (11.74 mg/100 g), total volatile base nitrogen (84.33 mg/100 g) and total viable count (4.80 Log CFU/g), but had higher astaxanthin content (12.53 ± 0.12 µg/g) than DS and DS + C. The results suggested that the developed C + CONE coating has potential to be used as active coating for preserving food quality.
Asunto(s)
Quitosano , Aceites Volátiles , Conservación de Alimentos/métodos , Quitosano/química , Cinnamomum zeylanicum/química , Aceites Volátiles/farmacología , Aceites Volátiles/química , XantófilasRESUMEN
Bio-based hydrophobic coating modified cotton fabrics with durable flame retardancy are of high interest in the application of oil-water separation for not only avoiding the use of hazardous substances but also improving the fire safety during use. Herein, phytic acid@Polyurushioltitanium complex coated cotton fabric was developed using the facile dip-coating method involving the sequential immersion in the solution of poly(ethyleneimine), phytic acid, titanium oxide, and urushiol. The underlying coating accommodated abundance of phytic acid, which imparted excellent flame retardancy to cotton fabric, and the top coating composed of the polyurushioltitanium complex endowed cotton fabric with high hydrophobicity that the water contact angle (WCA) was up to 149.8°. The hydrophobicity also guaranteed effective protection of the underlying phytic acid against chemical solvents and abrasion. Besides, the hydrophobic coating allowed cotton fabric for good self-cleaning and effective oil-water separation. Therefore, the preparation of phytic acid@polyurushioltitanium complex coated cotton fabric offers a promising approach to construct durable biomass-coated cellulose-based fabric with multifunctionality.
Asunto(s)
Fibra de Algodón , Ácido Fítico , Titanio , Textiles , Agua/químicaRESUMEN
Flexible polyurethane foam (FPUF) is widely used in our life, but it is inherent flammable. The demand for environmental-friendly multi-functional FPUF has been increasing rapidly in the last decade. In this work, a novel bio-based flame retardant coating was constructed by chemically reacting sodium alginate (OSA) and polydopamine (PDA) on the FPUF, followed by depositing nanorod-like ß-FeOOH molecules through complexation reaction to form a biomimetic structure. The limiting oxygen index of the coated FPUF samples reached 25.5%. The peak heat release rate was reduced by 45.0%, and the smoke density of the coated sample was decreased by 69.1% compared to that of the control FPUF sample. It was proposed that the OSA-PDA-ß-FeOOH decomposed during combustion to promote the formation of compact crosslinked char and released inert gases to dilute the combustible gases, and the ß-FeOOH transferred to Fe2O3 to settled the smoke particles reducing the smoke release. Furthermore, the coating with shark skin like structure endowed FPUF antibacterial ability because of its good superoleophobicity underwater. This work provided a novel strategy to construct a biomimetic multifunctional coating on the FPUF.
Asunto(s)
Antibacterianos , Retardadores de Llama , Antibacterianos/farmacología , Biomimética , HumoRESUMEN
Bio-based controlled release fertilizers (BCRFs) are cost-effective and renewable thus gradually replacing petroleum-based controlled release fertilizers (CRFs). However, most of the study mainly focused on modifying BCRFs to improve controlled-release performance. It is necessary to further increase the functionality of BCRF for expanding the application. A multifunctional double layered bio-based CRF (DCRF) was prepared. Urea was used as the core of fertilizer, bio-based polyurethane was used as the inner coating, and sodium alginate and copper ions formed the hydrogel as the outer coating. In addition, mesoporous silica nanoparticles loaded with sodium selenate was used to modify the sodium alginate hydrogel (MSN@Se hydrogel). The results showed that the nitrogen longevity of the DCRF was much better than that of urea and BCRF. The selenium nutrient longevity of the DCRF was 40 h, much longer than that of sodium selenate. The DCRF improved the yield and nutritive value of cherry radish (Raphanus sativus L. var.radculus pers) with the elevated contents of selenium, an essential trace element. Moreover, the DCRF showed inhibitory effect on Fusarium oxysporum Schltdl. and could resist soil-borne fungal diseases continuously. Overall, this multifunctional fertilizer has great potential for expanding the use of BCRFs for sustainable development of agriculture.
Asunto(s)
Raphanus , Selenio , Poliuretanos , Fertilizantes/análisis , Preparaciones de Acción Retardada , Antifúngicos , Ácido Selénico , Suelo , Nitrógeno/análisis , UreaRESUMEN
Textiles with efficient moisture management provide a comfortable microenvironment for human body. However, little attention has been paid to sweat-induced bacterial growth alongside. In this study, chitooligosaccharide (COS) was used to modify lysozyme (Lyz-COS) to obtain more excellent antibacterial activity. Lyz-COS could undergo an amyloid-like aggregation by reducing its disulfide bond and hydrogen bond triggered by thiourea dioxide (TD). The Phase-Transited Lyz-COS (PTL-COS) coating increases the hydrophilicity and antibacterial properties of wool fabrics, which can withstand 50 washing cycles and 100 rubbing cycles. In addition, two methods are proposed to customize Janus wool fabrics as desired. Method 1: The PTL-COS film was prepared first, and then the film was transferred to one side of the wool fabric. Method 2: Simply spray the PTL-COS solution on one side of the wool fabric. These two processes are simple to operate and can be customized on demand, enabling single transport of sweat and inhibiting sweat-induced bacterial growth. This work underlines the significance of chitooligosaccharide-modified PTL coatings for functionalization of textile surfaces and provides new insights into the development of more adaptable and smarter textiles and clothing.
Asunto(s)
Muramidasa , Fibra de Lana , Animales , Antibacterianos/química , Quitosano , Humanos , Muramidasa/análisis , Oligosacáridos , Textiles , Lana/químicaRESUMEN
A novel polymer-coated nitrogen (N) fertilizer was developed using bio-based polyurethane (PU) derived from liquefied locust sawdust as the coating material. The bio-based PU was successfully coated on the surface of the urea fertilizer prills to form polymer-coated urea (PCU) fertilizer for controlled N release. Epoxy resin (EP) was also used to further modify the bio-based PU to synthesize the interpenetrating network (IPN), enhancing the slow-release properties of the PCU. The N release characteristics of the EP-modified PCU (EMPCU) in water were determine at 25 °C and compared to that of PCU and EP-coated urea (ECU). The results showed that the EP modification reduced the N release rate and increased the longevity of the fertilizer coated with bio-based PU. A corn growth study was conducted to further evaluate the filed application of the EMPCU. In comparison to commercial PCU and conventional urea fertilizer, EMPCU was more effective and increased the yield and total dry matter accumulation of the corn. Findings from this work indicated that bio-based PU derived from sawdust can be used as coating materials for PCU, particularly after EP modification. The resulting EMPCU was more environmentally friendly and cost-effective than conventional urea fertilizers coated by EP.