In general, the poultry industry uses 0.5-1 ppm chlorine solution in the meat sanitization process. However, chlorine can react with organic material and produce halogenated organic compounds, notably chloroform, which causes bladder and rectal cancer in humans. For this reason, many industries try to avoid chlorine. This study investigated the efficacy of ultrasound and plasma-activated water (pAW) on the inactivation of Escherichia coli and Staphylococcus aureus in chicken muscle, rough skin, and smooth skin. Samples inoculated with bacteria suspension were treated by ultrasound alone and PAW-ultrasound. The Taguchi method and desirability function approach were used for the experimental design and optimization. Combined ultrasound and PAW inactivated up to 1.33 log CFU/ ml of E. coli K12 and 0.83 log CFU/ml of S. aureus at a sample thickness of 4 mm, at 40 °C for 60 min, while pAW alone only reduced E. coli K12 by 0.46 log CFU/ml and S. aureus by 0.33 log CFU/ml under the same condition. The muscle topography showed a porous structure, which facilitated the penetration of PAW. The color measurements of muscle treated with ultrasound and PAW-ultrasound were dramatically different from the untreated sample, as also perceived by the sensory evaluation panel. Therefore, the synergistic interaction of combined PAW-ultrasound could be used to enhance microbial inactivation in meat. In the past, sanitization by the chilling process with circulation system in the poultry industry used ice and 0.5-1 ppm chlorine to decrease the temperature of chicken carcass and lower the bacterial load in the gizzard and intestine. However, this process can cause cross-contamination because of circulated poultry water in the chiller tank. Additionally, chlorine can react with organic materials and produce halogenated organic compounds, notably, chloroform, which causes bladder and rectal cancer in humans. Various technologies have since been developed to reduce the bacteria in chicken meat, such as bacteriophage (ListShield ™) combined with UV-C light reduced Listeria monocytogenes 2.04 log CFU/ml 1 , ultrasound combined with a chemical immersion (lactic acid, sodium decanoate, and trisodium phosphate) reduced 0.73 log CFU/ml of Campylobacter jejuni, 1.02 log CFU/ml of TVC, and 1.37 log CFU/ml of total Enterobacteriaceae 2 , electrolyzed water reduced 1.0 log CFU/ml of microbial reduction 3 , non-thermal plasma jet with N 2 /O 2 gas reduced 0.66 log CFU/g of Salmonella typhimurium 4 , cold atmospheric plasma pen with He/O 2 gas reduced 3 log CFU/ml of L. innocua on muscle 5 , and dielectric barrier discharge plasma reduced 3.11 log CFU/ml of C. jejuni on skin 6. The past decade has focused on an environmentally-clean sanitizing technology called non-thermal plasma, particularly plasma-activated water (PAW). PAW can be used as a bacterial disinfection reagent in mass

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The biomaterials polylactic acid (PLA), polycaprolactone (PCL), and hydroxyapatite (HA) were selected to fabricate composite filaments for 3D printing fused filament fabrication (FFF), which was used to fabricate a composite biomaterial for an interlocking nail for canine diaphyseal fractures instead of metal bioinert materials. Bioactive materials were used to increase biological activities and provide a high possibility for bone regeneration to eliminate the limitations of interlocking nails. HA was added to PLA and PCL granules in three ratios according to the percentage of HA: 0%, 5%, and 15% (PLA/PCL, PLA/PCL/5HA, and PLA/PCL/15HA, respectively), before the filaments were extruded. The test specimens were 3D-printed from the extruded composite filaments using an FFF printer. Then, a group of test specimens was coated by silk fibroin (SF) using the lyophilization technique to increase their biological properties. Mechanical, biological, and chemical characterizations were performed to investigate the properties of the composite biomaterials. The glass transition and melting temperatures of the copolymer were not influenced by the presence of HA in the PLA/PCL filaments. Meanwhile, the presence of HA in the PLA/PCL/15HA group resulted in the highest compressive strength (82.72 ± 1.76 MPa) and the lowest tensile strength (52.05 ± 2.44 MPa). HA provided higher bone cell proliferation, and higher values were observed in the SF coating group. Therefore, FFF 3D-printed filaments using composite materials with bioactive materials have a high potential for use in fabricating an interlocking nail for canine diaphyseal fractures.

The full-thickness articular cartilage defect (FTAC) is an abnormally severe grade of articular cartilage (AC) injury. An osteochondral autograft transfer (OAT) is the recommended treatment, but the increasing morbidity rate from osteochondral plug harvesting is a limitation. Thus, the 3D-printed bilayer’s bioactive-biomaterials scaffold is of major interest. Polylactic acid (PLA) and polycaprolactone (PCL) were blended with hydroxyapatite (HA) for the 3D-printed bone layer of the bilayer’s bioactive-biomaterials scaffold (B-BBBS). Meanwhile, the blended PLA/PCL filament was 3D printed and combined with a chitosan (CS)/silk firoin (SF) using a lyophilization technique to fabricate the AC layer of the bilayer’s bioactive-biomaterials scaffold (AC-BBBS). Material characterization and mechanical and biological tests were performed. The fabrication process consists of combining the 3D-printed structure (AC-BBBS and B-BBBS) and a lyophilized porous AC-BBBS. The morphology and printing abilities were investigated, and biological tests were performed. Finite element analysis (FEA) was performed to predict the maximum load that the bilayer’s bioactive-biomaterials scaffold (BBBS) could carry. The presence of HA and CS/SF in the PLA/PCL structure increased cell proliferation. The FEA predicted the load carrying capacity to be up to 663.2 N. All tests indicated that it is possible for BBBS to be used in tissue engineering for AC and bone regeneration in FTAC treatment.

In this study, Chitosan (CS), Silk Fibroin (SF), and Hydroxyapatite (HA) were selected for scaffold fabrication. The scaffolds were fabricated by freeze drying technique to produce a porous structure. Silk cocoons and bovine bone were used to synthesize the SF and HA, respectively. While CS was produced from commercialized product made from squid pen. The CS was selected as a main structure of the scaffold which was fixed at 50% by weight ratio of the specimen. Another fifty percent are the various ratio of HA and SF. The result confirmed the extraction of silk cocoons and bovine bones were acceptable used as HA and SF. The HA and SF ratio that provided the highest porosity percentage was 25:25, while the highest percentage of cells growth in 7 and 21 days was 50:0 ratio. According to MTT-assay results, the scaffolds in every ratio could be used as a tissue engineering structure for cell proliferation as well as cartilage repairing in the future.