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The antioxidant and antibacterial potentials of essential oils and acetone extracts of black pepper, cumin, black cumin and mace were carried out by different techniques. The antioxidative capacity of the essential oils and acetone extracts were evaluated against mustard oil by measuring peroxide and thibarbituric acid values at fixed intervals. In addition, their antioxidant potential was evaluated by 2, 2′‐diphenyl‐1‐picrylhydracyl radical and conjugated diene assays. Their reducing power was determined with standards, which proved the strong antioxidant capacity of essential oils and extracts. The antioxidant activity of essential oils and extracts exerted by all the antioxidant assays can be compared with synthetic antioxidants such as butylated hydroxyanisole and butylated hydroxytoluene. The antibacterial activity was studied by disk diffusion and poison food methods. Black cumin essential oil showed complete zone of inhibition (P < 0.05) against tested bacterial strains of Staphylococcus aureus, Bacillus cereus and Bacillus subtilis at 2 and 6 µL level by disk diffusion method. Black cumin and black pepper extracts showed complete reduction of colonies against tested bacterial strains of S. aureus, B. cereus and B. subtilisat 5 and 10 µL level by poison food method. Poison food method exhibited good results for the tested essential oils and extracts. Essential oils of black pepper, cumin, black cumin and mace may be used to stabilize mustard oil after screening.

Owing to the high incidences of toxigenic moulds and mycotoxins in the study area, there is a need for the creation of mycotoxin awareness among maize farmers of India to control the chronic adverse health effects on humans and livestock due to mycotoxins.

This study describes the selection of single-stranded DNA (ssDNA) aptamers against Salmonella enterica serovar Typhimurium using a modified whole cell systematic evolution of ligands by exponential enrichment (whole cell SELEX). For evolving specific aptamers, ten rounds of selection to live Salmonella cells, alternating with negative selection against a cocktail of related pathogens, were performed. The resulting highly enriched oligonucleotide pools were sequenced and clustered into eight groups based on primary sequence homology and predicted secondary structure similarity. Fifteen sequences from different groups were selected for further characterization. The binding affinity and specificity of aptamers were determined by fluorescence binding assays. Aptamers (SAL 28, SAL 11, and SAL 26) with dissociation constants of 195 ± 46, 184 ± 43, and 123 ± 23 nM were used to develop a nanogold-based colorimetric detection method and a sedimentation assay. The former showed a better sensitivity limit of 10(2) CFU/mL using aptamer SAL 26. This approach should enable further refinement of diagnostic methods for the detection of Salmonella enterica serovar Typhimurium and of other microbial pathogens.

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