BACKGROUND: Poultry meat belongs to perishable foods and the major concern of food industries is the microbial spoilage of poultry meat. OBJECTIVES: The aim of present study was to investigate the effect of chitosan (CH) coating enriched with different concentrations of Ziziphora clinopodioides essential oil (ZEO) in comparison with control group on some of the sensory and microbial properties of chicken breast fillets during storage at refrigerated temperature for 12 days.   METHODS: Essential oil extraction was done by hydro-distillation method and its chemical composition was determined by gas chromatography with mass spectrometry (GC-MS). In the present study, chicken breast fillets separately were dipped in 2% CH solution containing ZEO at concentrations 0, 0.5 and 1% and then stored at refrigerated condition for 12 days. After that chicken fillets were studied at 7 intervals (0, 1, 3, 5, 7, 9 and 12 days) regarding microbial (Total mesophilic and Psychrotrophic bacteria, Pseudomonas spp. and Enterobacteriaceae) and sensory (color, odor and taste) examination. RESULTS: The most important compounds of the ZEO were geraniol (20.62%), carvacrol (18.17%), thymol (5.39%), α-terpineol (7.49%) and 4-terpineol (6.83%). Results of this study revealed that in the treatments coated with CH containing ZEO, total viable counts (TVC), Pseudomonas spp., lactic acid bacteria, Psychrotrophic bacteria and Enterobacteriaceae familysignificantly (P<0.05) decreased as compared to control group during the storage period. Based on the results of the present study, coating of chicken fillets with chitosan alone or chitosan containing 0.5 % concentration of ZEO showed better sensory properties. CONCLUSIONS: CH coating enriched with 0.5 % ZEO has potential to extend shelf life of chicken fillets without any unfavorable organoleptic properties.

Introduction: The development of Jembrana disease vaccine is an important effort to prevent losses in the Bali cattle industry in Indonesia. This study aims to prepare a Jembrana DNA vaccine encoding the transmembrane portion of the envelope protein in pEGFP-C1 and test the success of its delivery in culture cells using a chitosan-DNA complex. Material and Methods: Cloning of the DNA vaccine was successfully performed on E. coli DH5α and confirmed by colony PCR, restriction analysis and sequencing. The plasmids were prepared as a chitosan complex using the complex coacervation method and physicochemically characterised using a particle size analyser. A transfection assay was performed in HeLa cells with 4 h exposure, and mRNA expression was assessed at 24 h post transfection. Results: With a 1:2 (wt./wt.) ratio of DNA and chitosan, the complexes have a mean diameter of 236 nm, zeta potential value of + 17.9 mV, and showed no high toxicity potential in the HeLa cells. This complex successfully delivered the DNA into cells, as shown by the presence of a specific RT-PCR product (336 bp). However, the real-time PCR analysis showed that the delivery with chitosan complex resulted in lower target mRNA expression when compared with a commercial transfecting agent. Conclusion: pEGFP-env-tm JDV as a candidate vaccine can be delivered as the chitosan-DNA complex and be expressed at the transcription level in vitro. This initial study will be used for further improvement and evaluation in vivo.