Multidrug-resistant (MDR) Salmonella enterica serovar Agona infections affect public health globally. This investigation aimed to ascertain the antimicrobial resistance profiles and molecular characteristics of Salmonella Agona isolates obtained from food-producing animals. A total of 209 Salmonella Agona isolates were recovered from mostly chickens (139 isolates), pigs (56 isolates), cattle (11 isolates), and ducks (3 isolates) between 2010 and 2020 in South Korea. In addition, these Salmonella Agona isolates were obtained from 25 slaughterhouses nationwide. Furthermore, this serotype suddenly increased in chickens in 2020. Salmonella Agona from chickens showed high resistance (69-83%) to ampicillin, streptomycin, tetracycline, trimethoprim/sulfamethoxazole, and chloramphenicol. Moreover, chicken/duck isolates (83.1%) showed significantly higher levels of MDR than cattle/pig isolates (1.5%). For molecular analysis by pulsed-field gel electrophoresis, infrared spectroscopy biotyping, and multilocus sequence typing in combination, a total of 23 types were observed. Especially two major types, P1-III-2-13 and P1-IV-2-13, comprised 59.3% of the total isolates spreading in most farms. Moreover, Salmonella Agona sequence type (ST)13 was predominant (96.7%) among three different STs (ST13, ST11, and ST292) widely detected in chickens (94.3%) in most farms located nationwide. Taken together, MDR Salmonella Agona in chickens might pose a potential risk to public health through direct contact or the food chain.
To study the leaves of Adiantum philippense L. for their antioxidant, cytotoxicity and thrombolytic activities and to perform phytochemical evaluation. Methods: In-vitro antioxidant activity of extract was studied using DPPH radical scavenging, reducing power, total phenol and total flavonoid content determination assays. The cytotoxic activity was determined using brine shrimp lethality bioassay, thrombolytic activity by clot disruption and phytochemical potential by qualitative analysis. Results: The antioxidant activity of the extracts was found promising. The reducing power of this crude extract increase with the increase of concentration; IC50 values of DPPH scavenging activity was (140.00±0.86) μg/mL as compared to ascorbic acid [IC50 (130.00±0.76) μg/mL];Total phenol and total flavonoids content were (148.26±0.24) mg/mL and (163.06±0.56) mg/mL respectively. In cytotoxicity assay the LC50 values of the sample was (106.41±0.78) μg/mL where as for standard vincristin sulphate was (08.50±0.24) μg/mL as a positive control and the extract shows (12.86±1.02)% clot lytic whereas standard streptokinase shows (30.86±0.44% clot lytic activity in thrombolytic assay. The phytochemical evaluation indicates the presence of chemical constituents including carbohydrates, alkaloids, saponins, glycosides, flavonoids. Conclusions: This study shows that the methanol extract of leaves of Adiantum philippense L. has bioactivity but further compound isolation is necessary to confirm the activities of individual compounds.
