Preparation and characterization of chitosan/whey isolate protein active film containing TiO2 and white pepper essential oil.

Active packaging films are designed to improve quality and extend the food shelf life by incorporating functional active ingredients into biopolymer films. This study developed a bioactive film based on chitosan (CS) and whey isolated protein (WPI) incorporated with 0.01 wt% TiO2 and 0.1 wt% white pepper essential oil (WPEO). The physicochemical properties of the prepared film were also evaluated comprehensively. The results showed that water solubility and water vapor permeability of the film incorporated with TiO2 and WPEO were 25.09% and 0.0933 g mm m-2 h-1 KPa-1, respectively, which were significantly higher than those of other films (P < 0.05). In addition, the UV barrier properties of films incorporating TiO2 and WPEO have improved. The films were characterized by Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). The FTIR results showed interactions between TiO2 and WPEO with CS/WPI compound, and the SEM results indicated a good incorporation of TiO2 into the composite films. The antioxidative and antibacterial properties of films were significantly enhanced by incorporating WPEO. According to results, the developed biocomposite film can be considered as a packaging material.

Study on Screening the High-Efficiency Predominant Bacteria for Decompounding the Organic Wastes in Rubber Industry Wastewater / 环境与健康杂志

Objective To screen the high-efficiency predominant bacteria which can decompound 2-mercaptobenzothiazole, the accelerant for producing latex, in the organic wastewater. Methods Sampling from manufacturing environment, we got the predominant bacteria by primary screening, isolating and functional tests, and performed simulated test ground decompounding tests by using all bacteria. The enrichment of the predominant bacteria was followed by screen and identification to select the high-efficiency bacteria. Results 75 strains of predominant bacteria were obtained by primary screening. The simulated decompounding tests were performed after the mixed bacteria were tamed. The ratio of elimination for chemical oxygen demand (COD) was about 60.8%-97.7%, and the average was 77.2%. The predominant bacteria adhered to the surface of the active carbon, the carrier, and formed the biological film. Through screening and identification the Bacillus cereus showed to be predominant (90%). Conclusion The technology of high-efficiency predominant bacteria can be used for decompounding 2-mercaptobenzothiazole in the organic wastewater.