Development of novel isothermal-based DNA amplification assay for detection of pig tissues in adulterated meat.

For the first time, we describe an innovative polymerase spiral reaction (PSR) assay for the rapid, simple, and accurate detection of pig tissues or pork in adulterated meat including heat-treated and processed ones. The PSR assay specifically targeting the mitochondrial cytochrome b (cyt-b) gene of the pig was successfully optimized permitting assay results in 65 min time. The developed detection method was 100% specific amplifying only the cyt-b gene and displaying negative results with all the tested non-pork meats. The sensitivity of the developed PSR (760 fg porcine DNA) was tenfold better than the end-point PCR and able to detect heat-treated (121 °C) and adulterated (0.5% pork in beef) meat and processed pork products such as sausages, salami, meatball, soup, curry, etc. The developed PSR-based method can be used for point-of-care detection with minimum instrumentation and technical expertise to guarantee instant clearance of exported and imported meat products. This is the first time that PSR has been adapted for food authenticity purposes.

Prevalence of Arcobacter spp. in humans, animals and foods of animal origin including sea food from India.

The present study reports the prevalence of Arcobacter, an emerging pathogen in human, animals and foods of animal origin in India. A total of 600 samples from various sources, viz. diarrhoeal stools of humans and dogs, faecal swabs of animals (pig, poultry), preputial washings of breeding bulls and food samples (chicken, pork, fish) were examined for presence of Arcobacter spp. Using cultural methods, a total of 63 Arcobacter spp. were isolated of 600 (10.50%) samples with highest isolation rate were from pig faeces (21.33%) followed by sea foods (17.33%), poultry faeces (14.67%), pork (16.00%), chicken meat (12.00%) and human stools (2.67%). The isolates were confirmed as arcobacters by genus-based PCR. PCR screening of all the enriched samples revealed the overall prevalence of Arcobacter spp. to be 12.00% with highest in pig (25.33%), followed by sea food (21.33%), poultry (17.33%), pork (16%), chicken meat (12%) and human stools (4.00%). No Arcobacter spp. was isolated or detected from diarrhoeal faecal samples of dogs and preputial washings. With multiplex PCR, three different species were detected (A. butzleri, A. cryaerophilus and A. skirrowii) with most of the samples showing mixed infections. There are only two recent reports from India; one with cultural isolation and another with PCR detection of Arcobacter spp. in stool samples of humans with clinical diarrhoea. In this context, our present report is the first report of isolation and detection of Arcobacter spp. from various sources of animals and foods including diarrhoeic human stool samples, utilizing both cultural and molecular tools identifying arcobacters at genus and species level. These results support the importance of arcobacters as an emerging food-borne pathogen, possessing zoonotic potential.