Isolation, Purification and Characterization of Antioxidative Bioactive Elastin Peptides from Poultry Skin

Muscle-based by-products are often undervalued although commonly reported having a high amount of natural bioactive peptides. In this study, elastin was isolated from the protein of broiler hen skin while its hydrolysate was prepared using Elastase. Assessment of antioxidative properties of elastin-based hydrolysate (EBH) was based on three different assays; 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical and metal chelating ability. The EBH was purified further using ultrafiltration, gel filtration and Reverse- Phase High-Performance Liquid Chromatography (RP-HPLC). The IC50 of ABTS radical activities for EBH were decreased as EBH further purified using ultrafiltration (EBH III; 0.66 mg/mL)>gel filtration (EB-II; 0.42 mg/mL)>RP-HPLC (EB-II4; 0.12 mg/mL). The sequential identification of the peptide was done by matrix-assisted laser desorption/ ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/ TOF-MS) of the potent fractions obtained from RP-HPLC (EB-II4). The presence of hydrophobic amino acids (Val and Pro) in the peptide sequences could potentially contribute to the high antioxidant activity of EBH. The sequences GAHTGPRKPFKPR, GMPGFDVR and ADASVLPK were identified as antioxidant peptides. In conclusion, the antioxidative potential from poultry skin specifically from elastin is evident and can be explored to be used in many applications such as health and pharmaceutical purposes.

Genotyping and genetic diversity of Arcobacter butzleri and Arcobacter cryaerophilus isolated from different sources by using ERIC-PCR from India

BACKGROUND

Arcobacters are important zoonotic pathogens and are transmitted through food and water. They are implicated in causing enteritis in animals and humans. Among the Arcobacter species, a wide genetic diversity has been documented, which reflects continuous evolving nature of these pathogens.

OBJECTIVES

To genotype and to know the genetic diversity of Arcobacter spp. (Arcobacter butzleri and Arcobacter cryaerophilus) isolated from different sources in India.

METHODS

Enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) was performed using genomic DNA of 49 Arcobacter isolates (27 A. butzleri and 22 A. cryaerophilus), recovered from a total of 506 samples of chicken meat, poultry skin, dairy cow milk and human stool as template and employing published primers.

RESULTS

ERIC sequence was found to be present in all the 27 A. butzleri isolates which were grouped into 18 subtypes, while it was present in 20 out of 22 A. cryaerophilus isolates which were grouped into 14 subtypes. Less variation was observed within sequences of both the Arcobacter species as revealed in dendrogram analysis. The genotyping of A. butzleri isolates showed the presence of 2-8 distinct bands (∼150 to ∼1600 bp), while A. cryaerophilus showed 1-10 distinct bands (∼120 to ∼2900 bp).

CONCLUSION

This study is the first report regarding genetic diversity of Indian Arcobacter isolates using ERIC-PCR. Close clustering between arcobacters of human and animal origin are indicative of probable zoonotic significance. So for these purposes, further explorative studies are suggested which would also help revealing the possibility of epidemiological relationships of different Arcobacter spp. as well as their public health concerns.

Trisodium Phosphate and Cetylpyridinium Chloride Spraying on Chicken Skin to Reduce Attached Salmonella typhimurium

Spraying treatments with trisodium phosphate (TSP) and cetylpyridinium chloride (CPC) were evaluated for their effectiveness in reducing Salmonella typhimurium attached to chicken skins. Chicken skins with an area of 38.5 cm² were cut from the breast areas of pre-chill chicken carcasses, mounted in a plastic holder, and inoculated with S. typhimurium . The inoculated skins were sprayed with tap water, 10% (wt/vol) TSP, or 0.1 % CPC solutions at 10, 35, or 60°C and 206.8, 413.7, 620.5, 827.4, or 1034.2 kPa for 30 s. After spraying, each skin was rinsed with tap water, transferred to a plastic bag containing 50 ml buffered peptone water, and stomached for 1 min. The stomaching water was collected, diluted serially, plated on xylose lysine tergitol 4 (XLT4) agar and Petrifilm aerobic count plates, and incubated for 18 to 24 h at 37°C. The results showed that tap water spraying reduced S. typhimurium by 0.7 to 1.6 log, while the reduction ranges for TSP and CPC spraying treatments were 1.6 to 2.3 and 1.5 to 2.5 log, respectively. Greater reductions in the numbers of S. typhimurium were obtained in TSP spraying treatments in the high pressure range (620.5 to 1034.2 kPa) and in CPC spraying treatments at 10°C.