Publications by authors named "M Kumar"

7,341 Publications

Structural and functional characterization of a novel biosurfactant from Bacillus sp. IITD106.

J Hazard Mater 2021 Sep 15;423(Pt B):127201. Epub 2021 Sep 15.

Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi 110016, India. Electronic address:

Plant saponins are attractive biosurfactants and have been used to enhance phytoremediation. There are only limited reports on saponins produced by bacteria. Here, we report structural and functional characterization of a novel saponin produced by Bacillus sp. IITD106. Biosurfactant production was determined by emulsion index, drop collapse, oil displacement and hemolytic assays. The biosurfactant was stable over a range of temperature (30 °C to 70 °C), salinity (0-150 g liter) and pH (4-10). The surface tension of the medium reduced from 58.89 mN/m to 27.29 mN/m using the isolated biosurfactant. Chromatographic analysis revealed the biosurfactant to be a glycolipid. LCMS, FT-IR and NMR analysis identified the biosurfactant to be a saponin containing two sugar groups and a 5 ringed triterpene sapogenin unit. Genome sequencing of the strain revealed the presence of genes responsible for biosynthesis of saponin. Statistical optimization of culture medium resulted in 9.3-fold increase in biosurfactant production. Kinetics study of biosurfactant production performed in a stirred tank batch bioreactor resulted in 6.04 g liter and 6.9 g liter biomass and biosurfactant concentration, respectively. The biosurfactant was found to solubilize polycyclic aromatic hydrocarbons. The potential of cell free biosurfactant containing broth to enhance oil recovery was tested in a sand pack column and recovery of 63% of residual oil was observed. To our knowledge this is the first report of saponin production by any of the strains of Bacillus.
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http://dx.doi.org/10.1016/j.jhazmat.2021.127201DOI Listing
September 2021

Rescuing mitochondria in traumatic brain injury and intracerebral hemorrhages - A potential therapeutic approach.

Neurochem Int 2021 Sep 21:105192. Epub 2021 Sep 21.

Department of Neurosurgery, Medical College of Georgia, GA, USA; Department of Oral Biology and Diagnostic Sciences, Dental College of Georgia, GA, USA. Electronic address:

Mitochondria are dynamic organelles responsible for cellular energy production. Besides, regulating energy homeostasis, mitochondria are responsible for calcium homeostasis, signal transmission, and the fate of cellular survival in case of injury and pathologies. Accumulating reports have suggested multiple roles of mitochondria in neuropathologies, neurodegeneration, and immune activation under physiological and pathological conditions. Mitochondrial dysfunction, which occurs at the initial phase of brain injury, involves oxidative stress, inflammation, deficits in mitochondrial bioenergetics, biogenesis, transport, and autophagy. Thus, development of targeted therapeutics to protect mitochondria may improve functional outcomes following traumatic brain injury (TBI) and intracerebral hemorrhages (ICH). In this review, we summarize mitochondrial dysfunction related to TBI and ICH, including the mechanisms involved, and discuss therapeutic approaches with special emphasis on past and current clinical trials.
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http://dx.doi.org/10.1016/j.neuint.2021.105192DOI Listing
September 2021

Myopericytoma Involving Proximal Phalanx of Index Finger: Masquerading as Tenosynovial Giant Cell Tumor - A Case Report.

J Orthop Case Rep 2021 May;11(5):88-91

Department of Orthopaedics, Seth GS Medical College and KEM Hospital, Mumbai, Maharashtra. India.

Introduction: Myopericytoma (MPC) is an uncommon benign smooth muscle cell neoplasm which frequently arises in lower extremities, sparsely they can be found in upper extremities and head and neck region. Very few case reports are available in the literature documenting hand localization of this tumor.

Case Presentation: In this report, we present a case of 83-year-old male individual with a mass lesion on the proximal phalanx of index finger of the right hand. Recent trivial trauma led the patient to medical assistance. Imaging mimicked Giant cell tumor of tendon sheath due to site of the lesion. The lesion was excised surgically. The final diagnosis of the specimen confirmed by histopathology was MPC, a benign smooth-muscle cell neoplasm.

Conclusion: MPC is a rare entity; however, definitive diagnosis is often challenging because it mimics some malignant soft-tissue neoplasms. A multidisciplinary approach is required to identify this lesion as being benign and thus define the correct modality of treatment.
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http://dx.doi.org/10.13107/jocr.2021.v11.i05.2220DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8422008PMC
May 2021

Genomic Diversity of Pigeon Pea ( L. Millsp.) Endosymbionts in India and Selection of Potential Strains for Use as Agricultural Inoculants.

Front Plant Sci 2021 7;12:680981. Epub 2021 Sep 7.

Department of Plant Sciences, University of Oxford, Oxford, United Kingdom.

Pigeon pea ( L. Millsp. ) is a legume crop resilient to climate change due to its tolerance to drought. It is grown by millions of resource-poor farmers in semiarid and tropical subregions of Asia and Africa and is a major contributor to their nutritional food security. Pigeon pea is the sixth most important legume in the world, with India contributing more than 70% of the total production and harbouring a wide variety of cultivars. Nevertheless, the low yield of pigeon pea grown under dry land conditions and its yield instability need to be improved. This may be done by enhancing crop nodulation and, hence, biological nitrogen fixation (BNF) by supplying effective symbiotic rhizobia through the application of "elite" inoculants. Therefore, the main aim in this study was the isolation and genomic analysis of effective rhizobial strains potentially adapted to drought conditions. Accordingly, pigeon pea endosymbionts were isolated from different soil types in Southern, Central, and Northern India. After functional characterisation of the isolated strains in terms of their ability to nodulate and promote the growth of pigeon pea, 19 were selected for full genome sequencing, along with eight commercial inoculant strains obtained from the ICRISAT culture collection. The phylogenomic analysis [Average nucleotide identity MUMmer (ANIm)] revealed that the pigeon pea endosymbionts were members of the genera and . Based on phylogeny and cluster synteny, was revealed as the most common endosymbiont, harbouring genes similar to those of and . This symbiont type (e.g., strain BRP05 from Madhya Pradesh) also outperformed all other strains tested on pigeon pea, with the notable exception of an strain from North India (NBAIM29). The results provide the basis for the development of pigeon pea inoculants to increase the yield of this legume through the use of effective nitrogen-fixing rhizobia, tailored for the different agroclimatic regions of India.
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http://dx.doi.org/10.3389/fpls.2021.680981DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8453007PMC
September 2021

Radiologic Gastrostomy: An Unmet Need!

Indian J Radiol Imaging 2021 Apr 27;31(2):519-520. Epub 2021 Jul 27.

Department of Diagnostic Radiology, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Missouri.

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http://dx.doi.org/10.1055/s-0041-1733812DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8448208PMC
April 2021
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