Activity

Amyloid-like fibrils from food proteins possess unique functional properties for food and many other uses. This study reports the effect of hydrolytic heating (pH 2.0, 85 °C, 0-24 h) and incubation times (0-7 days) on the formation and physicochemical properties of amyloid fibrils based on soy protein isolates (SPI). The SPI hydrolysates and fibrils were characterized through AFM, Thioflavin T (ThT) fluorescence, SDS-PAGE, FTIR, solubility, particle size, and DSC. Stable amyloid-like protein fibrils were formed with 8-10 h of hydrolytic heating at 85 °C followed by 3 days of incubation at room temperature, as observed under AFM and confirmed with ThT assay. The fibrils contained significantly higher amounts of regular secondary structures than SPI. Incubation of the hydrolysates led to a slight increase of average particle sizes. Protein solubility near the isoelectric point (approximately pH 4.8) increased with longer hydrolytic heating (0-24 h). The hydrolysates and fibrils exhibited better gelling properties than the SPI. The DSC results revealed that hydrolysates from longer hydrolytic heating times (12 and 24 h) possessed stronger aggregation potential during heat treatment. This study provides useful information to manipulate the formation of protein fibrils and will benefit future research to explore their potential applications. The main aim of this research work was to incorporate modified hydroxyethylcellulose (HEC) into PDMS based polyurethanes. In the first part, modification of hydroxyethylcellulose was carried out by polymerizing lactic acid (LA) with HEC using ammonia water to prepare poly(lactic acid) grafted hydroxyethylcellulose (HEC-g-PLA). The maximum degree of grafting (59.5%) was achieved at 19 mole ratio of HEC/LA, 2 h, 80 °C (for activation) and 4 h, 90 °C (for reaction) with 0.74 degree of substitution. In the second part, hydroxyl terminated polybutadiene (HTPB) was reacted with isophorone diisocyanate to produce NCO-terminated polyurethane prepolymer which in turn extended by chain extender to synthesize polydimethyl siloxane hydroxyl terminated (PDMS) based polyurethanes. Effect of incorporation of HEC-g-PLA as a chain extender was studied by varying its mole ratio in PDMS based PUs. Characterization of HEC-g-PLA and all PDMS/HEC-g-PLA based polyurethane samples was carried out by using Fourier Transform Infrared (FTIR) and proton solid-state NMR (1H SS NMR). Biological behavior of synthesized samples was also tested by various biological activities and results indicated that incorporation of HEC-g-PLA in to PDMS based polyurethanes leads to improvement in antibacterial activity, anti-biofilm inhibition, biocompatibility and non-mutagenicity. Therefore, HEC-g-PLA/PDMS blended polyurethanes are promising biomaterials that have potential for various biomedical applications. Ethanol-treated starch (ETS) shows potentiality to be used for binder of pharmaceutical tablets. This study was aimed to evaluate the mechanical strength, structural and hydration properties of ETS tablets and ETS tablets containing lauric acid and ascorbic acid and their release behavior. ETS was prepared from cassava starch at the temperatures of 80, 90, and 100 °C. The active compounds were entrapped within the ETS tablets by two methods, including dry mixing and ethanol solubilisation. The results indicated that ETS tablets from temperatures of 80 °C showed granular shapes, had high friability and low crushing strength indexes, and dispersed and released active ingredients rapidly upon contact with water. Meanwhile, ETS tablets from temperatures of 90 and 100 °C exhibited non-granular particles, had low friability and high crushing strength indexes. Upon hydration, the tablets of non-granular ETS containing lauric acid eroded gradually and released active ingredients during tablet’s erosion, meanwhile ascorbic acid diffused out gradually from the swelled tablets. Virgibacillus salarius BM02 was identified as a highly exopolysaccharide (EPS) producing bacterium. The EPS production and its physico-chemical properties (intrinsic viscosity and total sugars/protein (TS/P) ratio) were optimized using Box-Behnken experimental design. Maximum EPS production of 5.87 g L-1 with TS/P ratio of 12.56 and intrinsic viscosity of 0.13 dL g-1 was obtained at optimal conditions of sucrose (4.0% w/v), peptone (0.75% w/v) and incubation period of 4.69 day. The monosaccharide composition of EPS was mannose, arabinose and glucose at a molar ratio of 1.00.260.08. The EPS showed high water solubility (38.5%), water holding capacity (514.46%) and foaming capacity (55.55%). The EPS showed moderate antioxidant activity in vitro and good emulsion stabilizing properties against several hydrophobic compounds. The emulsifying activity was stable at different temperatures, pH and ionic strength. Additionally, the acid hydrolysate of the EPS was evaluated as a carbon source for the mixotrophic cultivation of industrially important Spirulina platensis. click here It induced an enhancement of not only biomass production of S. platensis, but also cellular contents (pigments, proteins and lipids) leading to higher nutritional value. The present study focuses on the synthesis and evaluation of neomycin-loaded hydrogels as potential substrate for wound healing application. Herein, genipin crosslinked gelatin interpenetrated diosgenin-modified nanocellulose (DGN-NC) hydrogels were synthesized. The hydrogels’ chemical structures as well as surface morphology, mechanical property, and thermal behavior were characterized. Swelling analysis and gelation kinetics of the hydrogels were studied and the results obtained showed good swelling capacity as well as high gel yield. In addition, the prepared loaded hydrogels were evaluated for antibacterial activity against human pathogenic E. coli and S. aureus bacteria with inhibition capacity determined in the range of 50-88%. In vitro cytocompatibility and drug release studies were also explored under simulated physiological conditions achieving high cell viability and release percentage >80% and >90% after 24 h, respectively. In effect, the design hydrogels in the present study possess adequate incorporated antibacterial properties with significant potentials towards wound dressing and healing applications.