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The study was undertaken to unravel the culturable endophytic bacterial microbiome of Crocus sativus L. (saffron crocus) and consequently obtain potential leads to develop plant growth-promoting and biocontrol agents for increased productivity and sustainable cultivation. The endophytes formed 47 different operational taxonomic units (OTUs), spanning over 28 genera. The host was preferentially colonized by the genus Bacillus, followed by Burkholderia and Pantoea, respectively. Several endophytes possessed potential plant growth-promoting properties and inhibitory activities against the specific fungal pathogens of saffron. The endophytes, except for Microbacterium oxydans, did not cause any disease symptoms in the pot experiments. The selected cultures, Burkholderia gladioli, Streptomyces achromogenes, and three species of Bacillus, enhanced the host plant growth significantly. Based on the pot experiment results, two isolates, Bacillus mojavensis CS4EB32 and Burkholderia gladioli E39CS3, were selected for the field experiments. We obtained an increase of 67.5%, 69.8%, and 68.3% in the production of flowers with the individual and collective treatments, respectively. The treatments also enhanced the biomass of the plant and the length and weight of stigmas significantly. The endophyte treatments induced the expression of the pathway genes, resulting in a marked increase in the concentration of apocarotenoids. The study indicates that the dominant endophytes support plant growth and development in nature and present an opportunity for developing microbial formulations for the sustainability of saffron cultivation. [ABSTRACT FROM AUTHOR]

The present study entails the usefulness of thermophilic amidase-producing bacterium in the biotransformation of benzamide to benzohydroxamic acid (BHA). A bacterium Bacillus smithii IIIMB2907 was isolated from a soil sample collected from hot springs of Manikaran, Himachal Pradesh, India. The whole cells of the bacterium displayed versatile substrate specificity by exhibiting significant activity with a diverse range of amides. In addition, amidase from thermophilic bacterium was induced by adding Ɛ-caprolactam in the mineral base media. The optimum temperature and pH of acyltransferase activity of amidase enzyme were found to be 50 °C and 7.0, respectively. Interestingly, half-life (t1/2) of this enzyme was 17.37 h at 50 °C. Bench-scale production and purification of BHA was carried out at optimized conditions which resulted in the recovery of 64% BHA with a purity of 96%. Owing to this, the reported process in the present study can be considered of immense industrial significance for the production of BHA. [ABSTRACT FROM AUTHOR]