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In this study, the sorption of oil from seawater using chitosan grafted poly(butyl acrylate) copolymer was optimized using response surface methodology (RSM). The effect of various parameters such as time, initial oil concentration, temperature, sorbent dose, and agitation rate on the oil sorption capacity was investigated. Plackett-Burman design was utilized for screening the various sorption parameters. RSM was adopted to acquire the best sorption conditions of two chitosan derivatives namely; CS-g-poly(ButA10) and CS-g-poly(ButA20). In this respect, the Box-Behnken design was applied. A second-order-polynomial model indicated that the sorption was very useful and able to achieve highest sorption capacity ranged from 79.56 to 92.29 g/g using grafted chitosan derivatives compared to 35.2 g/g for native chitosan in 180 min, 41.23-50 g/L of oil concentration, 38°C-41°C at 155-160 rpm. These findings nominate the fabricated CS-g-poly(ButA10) sorbent as an effectual and promising oil sorbent for environmental control of crude heavy oil spills. [ABSTRACT FROM AUTHOR]

In this study, amylose, known as the food-grade biopolymers has been proved as a feasible solution for the controlled delivery of quercetin. The effect of reaction variables including reaction temperature, time, pH and quercetin addition amount on the content and conversion rate of quercetin was analyzed. Meanwhile, fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) provided evidence of quercetin complexation with amylose. Then, the molecular, cluster, and fractal structures of the complexes were investigated using 13C cross-polarization/magic angle spinning nuclear magnetic resonance (13C CP/MAS NMR) and small-angle X-ray scattering (SAXS). Furthermore, laser scanning confocal microscopy (CLSM) identified the precise encapsulation structure from direct observation and scanning electron microscope (SEM) was conducted to show that complexes displayed a larger size granule with smooth and angular appearance. From the antioxidant study, amylose/quercetin complexes presented effective scavenging capacity toward DPPH•. Besides, complexes showed high retention of quercetin in simulated stomach conditions but gradual release in simulated small intestine conditions. It was therefore confirmed that the amylose/quercetin complexes could be served as suitable carriers for the controlled release of quercetin in the digestive tract. The present research expanded the application range of starch, meanwhile proved an alternative application prospect for the ameliorative bioactive quercetin products. [ABSTRACT FROM AUTHOR]

Since chitosan and its amino-, cinnamo- or cinnamo-amino- derivatives are acid-soluble, the effect of acetic acid on hyaluronan (HA) macromolecules degraded by Cu(II) ions and ascorbate was examined to produce reactive oxygen species (ROS). Further, the effects of glutathione (GSH), chitosan and its derivatives, added individually or in combination, on the quenching of ROS and ABTS.+ cation radical were examined using rotational viscometry and ABTS assay, respectively. The results of the rotational viscometry indicated a rapid degradation of HA by ROS after the addition of acetic acid. Chitosan and its derivatives moderately decreased the rate of HA degradation, while GSH decreased the rate of HA degradation more significantly. Moreover, GSH enhanced the protection of HA macromolecules against their degradation in the presence of chitosan or its derivatives. The results of the ABTS assay confirmed the results of the rotational viscometry. The GSH in the combination with chitosan and its derivatives reduced ABTS.+ more intensively than when added individually. [ABSTRACT FROM AUTHOR]

• Potato trypsin inhibitor (PTI) was efficiently isolated from potato wastewater. • PTI was a protein rich in β-sheet conformation and antiparallel was predominant form. • PTI showed some heat resistance and wide adaptability to pH. • Inhibition of PTI was positively related with β-sheet and β-turn contents. • After in vitro gastrointestinal digestion, PTI retained most of trypsin inhibition. Potato trypsin inhibitor (PTI) was obtained from imitated potato wastewater through a sustainable method of sequential acid precipitation, salting out, and ultrafiltration. PTI had a favorable inhibition with the low IC 50 of 6.861 ± 0.107 mg/L. To explore stability of PTI against pH and heating treatment, PTI secondary structure was investigated by circular dichroism and inhibition was determined using the BAPNA method. The results indicated that PTI exerted a certain heat resistance and excellent stability over a wide pH range. Also, correlation analysis displayed β-sheet and β-turn contents of PTI had a positive correlation with inhibition, whereas α-helix and random coil contents were negatively correlated with inhibition. During in vitro digestion, the limited loss rate of activity (29.28%) and degree of hydrolysis (24.39%) suggested that PTI presented sufficient resistance to gastrointestinal digestion. These findings would extend beneficial hints to convert potato wastewater by-product into the potential anti-obesity ingredient in future. [ABSTRACT FROM AUTHOR]

• Hydrophilic and hydrophobic cavities were both used to co-load VC and β C. • The stability of β C was improved after co-loading VC and β C in liposomes. • The release kinetics and mechanisms of β C from L- β C and L-VC- β C were studied. Vitamin C (VC) and β -Carotene (β C) were selected to produce co-encapsulated liposomes using hydrophilic and hydrophobic cavities simultaneously by ethanol injection method. The results of liposomal structure characterized by particle size, polydispersity index, zeta-potential and transmission electron microscope showed that the microstructure of all liposomal samples was spherical without adhesion or break and the size of VC- β C-loaded liposome (L-VC- β C) was bigger than VC-loaded liposome (L-VC) or β C-loaded liposome (L- β C). The encapsulation efficiency (EE) of VC in L-VC- β C was significantly higher than that in L-VC, and the EE of β C in L-VC- β C had no significant change compared with that in L- β C. The free radical scavenging rate of L-VC- β C was significantly higher than that of L- β C, while it had no significant change compared with that of L-VC. In addition, the storage stability of β C in L-VC- β C improved greatly compared with that in L- β C. Furthermore, the zero order model was applied to understand the release kinetics of β C from L- β C and L-VC- β C in the stomach, whereas the Korsmeyr-Peppas model was chosen to describe the release of β C from two types of liposome in small intestine and their release mechanisms were mainly dominated by Fickian diffusion. It was significant to provide a new idea for using hydrophilic and hydrophobic cavities simultaneously in liposomes to design the multicomponent nutrient delivery system. [ABSTRACT FROM AUTHOR]

Synovial fluid is a viscous solution found in the cavities of synovial joints. The principal role of synovial fluid is to reduce friction between the articular cartilages of synovial joints during movement. The presence of high molar mass hyaluronan (HA) in this fluid gives it the required viscosity for its function as lubricant solution. Inflammation oxidation stress enhances normal degradation of hyaluronan causing several diseases related to joints. This review describes hyaluronan properties and distribution, applications and its function in synovial joints, with short review for using thiol compounds as antioxidants preventing HA degradations under inflammation conditions.