sodium-dodecyl-sulfate and 1-1-diphenyl-2-picrylhydrazyl

The functional gelatin/curcumin composite film was prepared using an emulsifier, sodium dodecyl sulfate (SDS). The composite films were characterized using field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FTIR). The FE-SEM test results showed that curcumin was evenly distributed in the gelatin polymer matrix to form a flexible composite film with a smooth surface. The addition of 1.5 % of curcumin improved the UV blocking effect by more than 99 % at a loss of 5.7 % of transparency compared to neat gelatin films. The addition of curcumin (up to 1 wt%) significantly improved mechanical and water vapor barrier properties. Also, the gelatin/curcumin composite films exhibited remarkable antimicrobial activity against foodborne pathogenic bacteria, E. coli and L. monocytogenes, and showed strong antioxidant activity comparable to ascorbic acid. Antibacterial and antioxidant gelatin/curcumin composite films with improved UV protection, water vapor barrier and mechanical properties have high potential in active food packaging applications.

Topics: Anti-Bacterial Agents; Antioxidants; Benzothiazoles; Biphenyl Compounds; Curcumin; Escherichia coli; Food Packaging; Gelatin; Listeria monocytogenes; Microbial Sensitivity Tests; Particle Size; Picrates; Sodium Dodecyl Sulfate; Stress, Mechanical; Sulfonic Acids; Surface Properties

Clove bud (Syzygium aromaticum) extract was added at concentrations of 0, 35, 75, and 115 μg/ml to ovine semen extenders in order to investigate the antioxidant activities of clove bud extract and its effects on semen quality parameters after cryopreservation of ram spermatozoa. The basic extender was composed of Tris, egg yolk, and glycerol. Two other extenders were prepared by substitution of egg yolk with either LDL or egg yolk+SDS. The DPPH inhibition test was employed to assess the antioxidant activity of clove bud extract. Results showed that, compared to vitamin E, clove bud extract had a higher antioxidant activity. Better sperm motility and movement characteristics (P<0.05) were observed in the semen diluted with medium containing egg yolk+SDS than in that containing egg yolk and LDL. Progressive motility and movement characteristics of the sperm were significantly improved (P<0.05) by adding 35 and/or 75 μg/ml of clove bud extract to semen extenders. Sperm viability and plasma membrane integrity were also higher (P<0.05) in the semen exposed to medium containing egg yolk+SDS and 75 μg of clove buds extract after cryopreservation processes. Higher levels of clove bud extract, however, had adverse effects on all the sperm quality parameters and significantly reduced (P<0.05) the motility, movement parameters, viability, and plasma membrane integrity of ovine sperm. It was concluded that the clove bud extract had an antioxidant potential that makes it useful for addition to semen extenders and that the best results are obtained with a maximum clove bud extract of 75 μg/ml. Moreover, the combination of egg yolk and a detergent was found to improve sperm quality after the cooling and freeze-thawing processes.

Topics: Animals; Antioxidants; Biphenyl Compounds; Cryopreservation; Cryoprotective Agents; Detergents; Egg Yolk; Lipoproteins, LDL; Male; Picrates; Plant Extracts; Semen Analysis; Semen Preservation; Sheep; Sodium Dodecyl Sulfate; Sperm Motility; Spermatozoa; Syzygium