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Context: Bombax malabaricum DC. (Bombacaceae) is a traditional Chinese herbal medicine used for the treatment of inflammatory conditions, diarrhea, fever, chronic inflammation, catarrhal affection, and as a diuretic. However, little information is available about its antioxidative activity. Objective: Water, 50% ethanol, and 80% acetone extracts from flowers of B. malabaricum were investigated for their in vitro antioxidant activity in this article for the first time. Then the relationships between antioxidant activity measured by different methods and total phenolic content (TPC) and total flavonoid content (TFC) were established. Materials and methods: The antioxidant activities of extracts from B. malabaricum flower were investigated including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, oxygen radical absorbance capacity (ORAC), reducing power, and inhibition on phosphatidylcholine liposome peroxidation. Results: Results showed that all the extracts possessed remarkable antioxidant capacity compared with ascorbic or gallic acids. Total antioxidant activities evaluated by ORAC assay of different extracts ranged from 700.03 to 1482.46 μμmol Trolox equivalents/g. The highest TPC of 130.38 mg gallic acid equivalents (GAE)/g was observed in 80% acetone extract, whereas the lowest TPC of 57.09 mg GAE/g was obtained in the water extract. Furthermore, TFC exhibited significant ( P < 0.05) positive correlations with DPPH radical-scavenging activity, ORAC, and reducing power. Discussion and conclusion: These findings demonstrate that the flowers of B. malabaricum have excellent antioxidant activities and thus might be a potential source of natural antioxidants. [ABSTRACT FROM AUTHOR]

The previous study indicated that cuminaldehyde (CUM) could be used as an antibacterial agent in sauced beef to reduce the propagation of Staphylococcus aureus (S. aureus). This research took sauced beef treated with 0.4 μL/mL CUM as the research object. Transcriptomic and proteomic methods were used to comprehensively analyze the changes in genes and proteins of S. aureus under CUM stress. A total of 258 differentially expressed genes (DEGs, 178 up-regulated and 80 down-regulated) and 384 differentially expressed proteins (DEPs, 61 up-regulated and 323 down-regulated) were found. It was observed that CUM destroyed the cell wall and cell membrane by inhibiting the synthesis of peptidoglycan and fatty acid. Low energy consumption strategies were formed by reducing glycolysis and ribosome de novo synthesis. The levels of genes and proteins associated with the glycine, serine, threonine, methionine, cysteine, and branched-chain amino acids were dramatically changed, which impaired protein synthesis and reduced bacterial viability. In addition, the up-regulated DEGs and DEFs involved in DNA replication, recombination and single-stranded DNA-binding contributed to DNA repair. Moreover, ATP-binding cassettes (ABC) transporters were also perturbed, such as the uptake of betaine and iron were inhibited. Thus, this study revealed the response mechanism of S. aureus under the stress of CUM, and provided a theoretical basis for the application of CUM in meat products. [Display omitted] • The response of S. aureus to cuminaldehyde stress was investigated by integrated transcriptomic and proteomic methods. • S. aureus responded to cuminaldehyde stress by up-regulating DNA repair proteins. • Cuminaldehyde destroyed the cell wall and cell membrane by inhibiting the synthesis of peptidoglycan and fatty acid. • Cuminaldehyde caused energy metabolism disorder and amino acids limitation. [ABSTRACT FROM AUTHOR]

A selective enrichment broth (SSL) was formulated to allow concurrent growth of 3 prominent food-borne pathogens: Salmonella enterica serovar Enteritidis, Staphylococcus aureus, and Listeria monocytogenes. Nalidixic acid, lithium chloride, and potassium tellurite were added as the selective agents, while sodium pyruvate and mannitol were employed as the supplemented elements. In the individual growth trial, the target pathogens were capable of growing in SSL to as high as 7-8 log(10) colony-forming units (CFU)/mL after 24 h incubation at 37 degrees C when being inoculated at 50-100 CFU/mL. In the simultaneous growth trial, the 3 combined target pathogens showed similar growth rates. The results show that SSL could support the successful simultaneous enrichment of 3 pathogens; however, SSL inhibited the growth of nontarget bacteria. In the artificial contaminated raw beef and ready-to-eat chicken, a high recovery of these 3 target pathogens was obtained in SSL. Finally, Salmonella Enteritidis, Staphylococcus aureus, and L. monocytogenes were detected from 710 suspicious food samples by SSL with real-time PCR, and no false-positive or -negative results were reported. In summary, SSL has been shown to be a suitable broth for the simultaneous detection of the 3 prominent food-borne pathogens by multipathogen detection on a single-assay platform.