Publications by authors named "Vishal A Ghadge"

Three new 22-membered polyol macrolides, dactylides A-C (1-3), were isolated from Dactylosporangium aurantiacum ATCC 23491 employing repeated chromatographic separations, and their structures were established based on detailed analysis of NMR and MS data. The relative configurations at the stereocenters were established via vicinal H-H coupling constants, NOE correlations, and by application of Kishi's universal NMR database. In order to get insights into the biosynthetic pathway of 1-3, the genome sequence of the producer strain D.

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The present study explores the endophyte associated with the halophyte Salicornia brachiata for uncovering new biologically important compounds. Thus, HPLC-PDA guided chemical investigation of the ethyl acetate extract of the Bacillus subtilis NPROOT3 led to the isolation of a new compound named bacillinaphthin A (1) along with previously known rubinaphthin A (2). The structure of 2 was determined by a comparison of HR-ESI-MS, H and C nuclear magnetic resonances (NMR) with those of reported data, whereas the structure of new compound 1 was elucidated by interpretation of 1D- and 2D-NMR and MS data.

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Lipopeptide (LP) biosurfactants from microbes have the potential to gradually replace chemical synthetic surfactants and fit the contemporary green and sustainable industrial production concept. However, their active participation is comparatively low in the global market pertaining to their low yield in microbial broth and costly downstream processes arising due to tedious isolation and purification methods. Herein, an efficient extraction method is developed that utilizes an aqueous biphasic system (ABS) comprising ionic liquids and polypropylene glycol 400 (PPG) to selectively extract a mixture of cyclic lipopeptides, namely, surfactin and fengycin from the culture broth of 5NPA-1, isolated from the halophyte Roxb.

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Article Synopsis
  • Melanin is a versatile biopolymer with potential uses in medicine, cosmetics, bioremediation, and bioelectronics, indicating its role in helping organisms manage environmental stresses.
  • Its biosynthesis occurs primarily in fungi and bacteria through two main pathways involving phenolic compounds, leading to various types of melanin, such as eumelanin and pheomelanin, facilitated by specific enzymes like tyrosinase and laccase.
  • Research aims to improve melanin production and extraction methods, given its low solubility and structural complexities, while comprehensive reviews are needed to guide future studies on microbial melanins and their applications.
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Extreme natural habitats like halophytes, marsh land, and marine environment are suitable arena for chemical ecology between plants and microbes having environmental impact. Endophytes are an ecofriendly option for the promotion of plant growth and to serve as sustainable resource of novel bioactive natural products. The present study, focusing on biodiversity of bacterial endophytes from Salicornia brachiata, led to isolation of around 336 bacterial endophytes.

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