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Gohulkumar M, Gurushankar K, Rajendra Prasad N, Krishnakumar N. Enhanced cytotoxicity and apoptosis-induced anticancer effect of silibinin-loaded nanoparticles in oral carcinoma (KB) cells. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2014; 41:274-82. [PMID: 24907761 DOI: 10.1016/j.msec.2014.04.056] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 03/09/2014] [Accepted: 04/23/2014] [Indexed: 01/08/2023]
Abstract
Silibinin (SIL) is a plant derived flavonoid isolated from the fruits and seeds of the milk thistle (Silybum marianum). Silibinin possesses a wide variety of biological applications including anticancer activities but poor aqueous solubility and poor bioavailability limit its potential and efficacy at the tumor sites. In the present study, silibinin was encapsulated in Eudragit® E (EE) nanoparticles in the presence of stabilizing agent polyvinyl alcohol (PVA) and its anticancer efficacy in oral carcinoma (KB) cells was studied. Silibinin loaded nanoparticles (SILNPs) were prepared by nanoprecipitation technique and characterized in terms of size distribution, morphology, surface charge, encapsulation efficiency and in vitro drug release. MTT assay revealed higher cytotoxic efficacy of SILNPs than free SIL in KB cells. Meanwhile, reactive oxygen species (ROS) determination revealed the significantly higher intracellular ROS levels in SILNPs treated cells compared to free SIL treated cells. Therefore, the differential cytotoxicity between SILNPs and SIL may be mediated by the discrepancy of intracellular ROS levels. Moreover, acridine orange (AO) and ethidium bromide (EB) dual staining and reduced mitochondrial membrane potential (MMP) confirmed the induction of apoptosis with nanoparticle treatment. Further, the extent of DNA damage (evaluated by comet assay) was significantly increased in SILNPs than free SIL in KB cells. Taken together, the present study suggests that silibinin-loaded nanoparticles can be used as an effective drug delivery system to produce a better chemopreventive response for the treatment of cancer.
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Krishnakumar N, Manoharan S, Palaniappan PLRM, Venkatachalam P, Manohar MA. Chemopreventive efficacy of piperine in 7,12-dimethyl benz [a] anthracene (DMBA)-induced hamster buccal pouch carcinogenesis: An FT-IR study. Food Chem Toxicol 2009; 47:2813-20. [DOI: 10.1016/j.fct.2009.08.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 07/20/2009] [Accepted: 08/31/2009] [Indexed: 11/29/2022]
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Krishnakumar N, Sulfikkarali NK, Manoharan S, Venkatachalam P. Raman spectroscopic investigation of the chemopreventive response of naringenin and its nanoparticles in DMBA-induced oral carcinogenesis. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 115:648-653. [PMID: 23880406 DOI: 10.1016/j.saa.2013.05.076] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 05/19/2013] [Accepted: 05/23/2013] [Indexed: 06/02/2023]
Abstract
Raman spectroscopy is a vibrational spectroscopic technique that can be used to optically probe the biomolecular changes associated with tumor progression. The aim of the present study is to investigate the biomolecular changes in chemopreventive response of prepared naringenin-loaded nanoparticles (NARNPs) relative to efficacy of free naringenin (NAR) during 7,12-dimethyl benz(a)anthracene (DMBA)-induced oral carcinogenesis by Fourier Transform Raman (FT-Raman) spectroscopy. Oral squamous cell carcinoma (OSCC) was developed in the buccal pouch of golden Syrian hamsters by painting with 0.5% DMBA in liquid paraffin three times a week for 14weeks. Raman spectra differed significantly between the control and tumor tissues, with tumors showing higher percentage signals for nucleic acids, phenylalanine and tryptophan and a lower in the percentage of phospholipids. Moreover, oral administration of free NAR and NARNPs significantly increased phospholipids and decreased the levels of tryptophan, phenylalanine and nucleic acid contents. On a comparative basis, NARNPs was found to have a more potent antitumor effect than free NAR in completely preventing the formation of squamous cell carcinoma and in improving the biochemical status to a normal range in DMBA-induced oral carcinogenesis. The present study further suggest that Raman spectroscopy could be a valuable tool for rapid and sensitive detection of specific biomolecular changes in response to chemopreventive agents.
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Palaniappan PLRM, Krishnakumar N, Vadivelu M. FT-IR study of the effect of lead and the influence of chelating agents, DMSA and D-Penicillamine, on the biochemical contents of brain tissues of Catla catla fingerlings. AQUATIC SCIENCES 2008; 70:314-322. [DOI: 10.1007/s00027-008-8053-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2025]
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Parthiban KT, Jude Sudhagar R, Cinthia Fernandaz C, Krishnakumar N. Consortium of Industrial Agroforestry:An Institutional Mechanism for Sustaining Agroforestry in India. CURR SCI INDIA 2019. [DOI: 10.18520/cs/v117/i1/30-36] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Gan J, Zheng J, Krishnakumar N, Goonatilleke E, Lebrilla CB, Barile D, German JB. Selective Proteolysis of α-Lactalbumin by Endogenous Enzymes of Human Milk at Acidic pH. Mol Nutr Food Res 2019; 63:e1900259. [PMID: 31271254 PMCID: PMC7231428 DOI: 10.1002/mnfr.201900259] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 05/03/2019] [Indexed: 01/01/2023]
Abstract
SCOPE The use of human milk products is increasing for high-risk infants. Human milk contains endogenous enzymes that comprise a dynamic proteolytic system, yet biological properties of these enzymes and their activities in response to variations including pH within infants are unclear. Human milk has a neutral pH around 7, while infant gastric pH varies from 2 to 6 depending on individual conditions. This study is designed to determine the specificity of enzyme-substrate interactions in human milk as a function of pH. METHODS AND RESULTS Endogenous proteolysis is characterized by incubating freshly expressed human milk at physiologically relevant pH ranging from 2 to 7 without the addition of exogenous enzymes. Results show that the effects of pH on endogenous proteolysis in human milk are protein-specific. Further, specific interactions between cathepsin D and α-lactalbumin are confirmed. The endogenous enzyme cathepsin D in human milk cleaves α-lactalbumin as the milk pH shifts from 7 to 3. CONCLUSIONS This study documents that selective proteolysis activated by pH shift is a mechanism for dynamic interactions between human milk and the infant. Controlled proteolysis can guide the use of human milk products based on individual circumstance.
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Palaniappan PLRM, Krishnakumar N, Vadivelu M, Vijayasundaram V. The study of the changes in the biochemical and mineral contents of bones of Catla catla due to lead intoxication. ENVIRONMENTAL TOXICOLOGY 2010; 25:61-67. [PMID: 19219934 DOI: 10.1002/tox.20475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In the present study, an attempt has been made to analyze the changes in the biochemical and mineral contents of lead-intoxicated bones of Catla catla at subchronic (15.5 ppm) exposure, and also to determine whether the effects of Pb intoxication can be reversed with the chelating agent meso 2, 3-dimercaptosuccinic acid (DMSA) on the bones of freshwater fingerlings Catla catla by using Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and atomic absorption spectrophotometer techniques. The FT-IR spectra of the lead-exposed bones show significant alteration in the biochemical constituents. The XRD analysis showed a decrease in crystallinity due to lead exposure. Further, the Ca, Mg, and P contents of the lead-exposed bones were less than those of the control group, and there was an increase in the mineral contents of the bones after DMSA treatment. In conclusion, the present study suggests that the subchronic lead exposure results in severe loss of bone minerals. The overall decrease in the FT-IR band intensity of Pb-exposed bones relative to the control indicates a decrease in the biochemical constituents like proteins and lipids. The increase in the band intensity after treatment with chelating agent DMSA indicates increased biochemical constituents, showing that the subchronic effects of lead can be reversed by DMSA. The amide I bands observed at 1654 cm(-1) in the present study suggest that the protein is dominated by alpha-helical structure.
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Krishnakumar N, Misra M, Dora S, Bohora SR. Entrapped catheter in the left ventricular posterior venous radicle of the coronary sinus in a case of hemianomalous pulmonary venous connection of left pulmonary veins to coronary sinus. Int J Cardiol 2007; 117:270-2. [PMID: 17336409 DOI: 10.1016/j.ijcard.2006.02.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2005] [Accepted: 02/24/2006] [Indexed: 11/23/2022]
Abstract
A 25-year old acyanotic lady with unclear pulmonary venous drainage and a dilated coronary sinus was catheterized. Left pulmonary veins drained into coronary sinus in a left pulmonary vein angiogram done through the coronary sinus with a National Institute of Health 7F catheter. After the angiogram, the catheter got entrapped in a coronary sinus tributary and could be removed only by surgery. The left pulmonary veins were rerouted into the left atrium by unroofing the coronary sinus. Surgery is the treatment of choice for entrapped catheters when the primary condition itself merits surgical correction.
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Krishnakumar N. OA03.15. A clinical study on the effect of ksheera vaitharana vasti in the management of gridrasi w.s.r. to sciatica. Anc Sci Life 2013. [PMCID: PMC4147508 DOI: 10.4103/0257-7941.123853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Purpose: Human beings are almost unique in standing upright posture balanced on two limbs. even though they are getting advantage of this posture,it also leads to considerable stress on the spine. the life style of a person has changed a lot in accordance with the time. As advancement of busy, professional and social life, improper sitting posture, jerking movements etc. all these causes undue pressure on the spine,as a result most common disorder of the spine low back ache occurs. Out of which 40% persons comes under sciatica. Gridhrasi is a soola pradhana vyadhi affecting the lower limbs with impairment of lifting of thigh. It can be compared with sciatica. In present study vaitharna vasthi mentioned in vangasena samhita in which goksheera as main ingredient is used to evaluate the effect in gridrasi. Method: Patients diagnosed as gridrasi according to classical signs and symptoms and positive SLR test were selected from O.P & I.P department of Dr.BRKR Govt. Ayurvedic Hospital. They were administered two cycles of vaitharana vasti in the form of yogavasti with gap of one week in between two cycles. Murchita tilataila is used for anuvasana. Saindava, guda, tilataila, amlika & goksheera are mixed in this order as vasthi vidhi. Result: The assessment of overall effect of therapy was based on both subjective and objective parameters. Subjective parameters include clinical features of gridrasi as per texts. Objective parameters include SLR test, numerical pain rating scale, oswestri disability index, X-ray of LS spine and MRI of LS spine. The results were found encouraging as there is significant reduction in pain & stiffness with improvement in straight leg raising. Conclusion: Vasthi is considered as the most powerful sodhana procedure and it is said to be ardha chikitsa. It is the most effective treatment for diseases which arising from vitiated vata. Since goksheera is the main in gradient, it is very effective in degenerative bony disorder or asthi dhatukshayajanya vikaras which is one of the main cause of sciatica.
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Krishnakumar N, Sivasankaran S, Harikrishnan S. Accidental sizing of patent foramen ovale during atrial septal defect sizing for device. Int J Cardiol 2006; 112:e40-1. [PMID: 16859782 DOI: 10.1016/j.ijcard.2006.02.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2005] [Accepted: 02/24/2006] [Indexed: 10/24/2022]
Abstract
A 21 year old lady with a 22 mm secundum atrial septal defect with adequate rims, and thin septum at the region of the fossa ovalis, but no additional atrial septal defect by transthoracic and transoesophageal echocardiogram was taken up for ASD sizing with a view to device closure. Initially, the ASD was sized to only 8 mm. However, the distal balloon was not fully opened out, and seemed to be conical with restricted opening. Inadvertent passage of sizing balloon through a patent foramen ovale (PFO) was immediately confirmed by transthoracic echocardiogram. The ASD was then recrossed and sized to 24 mm with normal opening out of the distal balloon. This was confirmed by transthoracic echocardiogram. A 28 mm ASD device was deployed across the ASD under transthoracic echocardiographic guidance with no residual flow.
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Maldonado-Gomez MX, Ng KM, Drexler RA, Conner AMS, Vierra CG, Krishnakumar N, Gerber HM, Taylor ZR, Treon JL, Ellis M, Garcia JKA, Cerney JP, Chapin DG, Kerns RT, Marcobal AM, Watkins SM, Amicucci MJ. A diverse set of solubilized natural fibers drives structure-dependent metabolism and modulation of the human gut microbiota. mBio 2025; 16:e0047025. [PMID: 40214223 PMCID: PMC12077125 DOI: 10.1128/mbio.00470-25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2025] [Accepted: 03/11/2025] [Indexed: 05/15/2025] Open
Abstract
Growing evidence suggests that inadequate dietary fiber intake, termed the "fiber gap," is linked to disease states through disruption of the gut microbiota. Despite this, our understanding of how various fiber structures influence the microbiota and health is limited by the lack of diverse commercially available fibers. Studies have primarily focused on a limited range of fibers, rather than the diverse array of fibers representative of those commonly found in our diets. In this study, we aimed to investigate how naturally derived fibers impact the human microbiota and their metabolic products. We performed a comprehensive structural characterization and functional evaluation of a unique and highly diverse set of new, highly soluble fibers with varied monosaccharide compositions, glycosidic linkages, and polymer lengths. Using an ex vivo high-throughput human microbiota platform coupled with metabolomic profiling, we demonstrate that these diverse fibers drive distinct and consistent microbial and metabolic profiles across cohorts of donors in a structure-dependent manner. These metabolic effects were accompanied by both general and donor-specific changes in microbial taxa. Finally, we demonstrate that integrating detailed glycomic characterization with microbial and metabolomic data allowed for prediction of functional outcomes driven by a novel material, pineapple pulp fiber. This work highlights the potential for targeted dietary fiber interventions to modulate the microbiota and improve health outcomes, paving the way for the development of new fiber-rich products with specific health benefits.IMPORTANCEFiber deficiency is associated with numerous disease states, many of which are linked to disruption of the gut microbiota. This study encompasses the first systematic and comprehensive characterization of a diverse collection of naturally derived solubilized fibers and their impacts on the microbiota. The results expand our understanding of the beneficial effects of specific carbohydrate structures naturally found in the human diet, highlighting the potential for designing fiber-based health interventions. The high solubility of these fibers increases both the range of products they can be incorporated in as well as their assayability in experiments, enabling a widespread increase in fiber consumption and positive health impacts.
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Marcobal AM, McConnell BR, Drexler RA, Ng KM, Maldonado-Gomez MX, Conner AMS, Vierra CG, Krishnakumar N, Gerber HM, Garcia JKA, Cerney JP, Amicucci MJ. Highly Soluble β-Glucan Fiber Modulates Mechanisms of Blood Glucose Regulation and Intestinal Permeability. Nutrients 2024; 16:2240. [PMID: 39064683 PMCID: PMC11279855 DOI: 10.3390/nu16142240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Revised: 07/05/2024] [Accepted: 07/10/2024] [Indexed: 07/28/2024] Open
Abstract
β-glucans found in cereal grains have been previously demonstrated to improve blood glucose control; however, current understanding points to their high viscosity as the primary mechanism of action. In this work, we present a novel, highly soluble, low-viscosity β-glucan fiber (HS-BG fiber) and a preclinical dataset that demonstrates its impact on two mechanisms related to the prevention of hyperglycemia. Our results show that HS-BG inhibits the activity of two key proteins involved in glucose metabolism, the α-glucosidase enzyme and the SGLT1 transporter, thereby having the potential to slow starch digestion and subsequent glucose uptake. Furthermore, we demonstrate in a multi-donor fecal fermentation model that HS-BG is metabolized by several different members of the gut microbiome, producing high amounts of short-chain fatty acids (SCFAs), known agonists of GPR43 receptors in the gut related to GLP-1 secretion. The production of SCFAs was verified in the translational gut model, SHIME®. Moreover, HS-BG fiber fermentation produces compounds that restored permeability in disrupted epithelial cells, decreased inflammatory chemokines (CXCL10, MCP-1, and IL-8), and increased anti-inflammatory marker (IL-10), which could improve insulin resistance. Together, these data suggest that the novel HS-BG fiber is a promising new functional ingredient that can be used to modulate postprandial glycemic responses while the high solubility and low viscosity enable easy formulation in both beverage and solid food matrices.
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Krishnakumar N, Krishnakumar S, Dalus MR, Balamugesh T. Yellow phosphorous poisoning--smoking stool syndrome. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 1997; 45:885-6. [PMID: 11229195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Krishnakumar N, Harikrishnan S, Tharakan JM. Self-blood letting in congestive cardiac failure. Int J Cardiol 2007; 114:135-6. [PMID: 16377009 DOI: 10.1016/j.ijcard.2005.11.054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Accepted: 11/15/2005] [Indexed: 10/25/2022]
Abstract
A 33-year-old male with idiopathic restrictive cardiomyopathy had dilated and tortuous veins over both lower limbs and over the scrotum with multiple hyperpigmented scars. He was in the habit of puncturing the veins to let out blood during episodes of worsening of dyspnoea, thereby relieving dyspnoea by decreasing the preload.
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Jensen N, Maldonado-Gomez M, Krishnakumar N, Weng CY, Castillo J, Razi D, Kalanetra K, German JB, Lebrilla CB, Mills DA, Taft DH. Dietary fiber monosaccharide content alters gut microbiome composition and fermentation. Appl Environ Microbiol 2024; 90:e0096424. [PMID: 39007602 PMCID: PMC11337808 DOI: 10.1128/aem.00964-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Accepted: 06/18/2024] [Indexed: 07/16/2024] Open
Abstract
Members of the mammalian gut microbiota metabolize diverse complex carbohydrates that are not digested by the host, which are collectively labeled "dietary fiber." While the enzymes and transporters that each strain uses to establish a nutrient niche in the gut are often exquisitely specific, the relationship between carbohydrate structure and microbial ecology is imperfectly understood. The present study takes advantage of recent advances in complex carbohydrate structure determination to test the effects of fiber monosaccharide composition on microbial fermentation. Fifty-five fibers with varied monosaccharide composition were fermented by a pooled feline fecal inoculum in a modified MiniBioReactor array system over a period of 72 hours. The content of the monosaccharides glucose and xylose was significantly associated with the reduction of pH during fermentation, which was also predictable from the concentrations of the short-chain fatty acids lactic acid, propionic acid, and the signaling molecule indole-3-acetic acid. Microbiome diversity and composition were also predictable from monosaccharide content and SCFA concentration. In particular, the concentrations of lactic acid and propionic acid correlated with final alpha diversity and were significantly associated with the relative abundance of several of the genera, including Lactobacillus and Dubosiella. Our results suggest that monosaccharide composition offers a generalizable method to compare any dietary fiber of interest and uncover links between diet, gut microbiota, and metabolite production. IMPORTANCE The survival of a microbial species in the gut depends on the availability of the nutrients necessary for that species to survive. Carbohydrates in the form of non-host digestible fiber are of particular importance, and the set of genes possessed by each species for carbohydrate consumption can vary considerably. Here, differences in the monosaccharides that are the building blocks of fiber are considered for their impact on both the survival of different species of microbes and on the levels of microbial fermentation products produced. This work demonstrates that foods with similar monosaccharide content will have consistent effects on the survival of microbial species and on the production of microbial fermentation products.
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Preethi Shree M, Forest College and Research Institute, Tamil Nadu Agricultural University, Mettupalayam, Tamil Nadu, India, Krishnakumar N, Parthiban KT, Forest College and Research Institute, Tamil Nadu Agricultural University, Mettupalayam, Tamil Nadu, India, Forest College and Research Institute, Tamil Nadu Agricultural University, Mettupalayam, Tamil Nadu, India. Genetic Diversity and Relationships of Neolamarckia cadamba (Roxb.) Bosser progenies through cluster analysis. TROPICAL PLANT RESEARCH 2018. [DOI: 10.22271/tpr.2018.v5.i1.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Masarweh C, Maldonado-Gomez M, Paviani B, Bhattacharya M, Weng CY, Suarez C, Ehlers-Cheang S, Stacy A, Castillo J, Krishnakumar N, Kalanetra KA, Barile D, German JB, Lebrilla CB, Mills DA. Generation of novel prebiotic oligosaccharide pools from fiber drives biological insight in bacterial glycan metabolism. Appl Environ Microbiol 2025; 91:e0207724. [PMID: 39912642 PMCID: PMC11921329 DOI: 10.1128/aem.02077-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2024] [Accepted: 01/14/2025] [Indexed: 02/07/2025] Open
Abstract
Prebiotic oligosaccharides are dietary supplements that modulate the intestinal gut microbiome by selectively nourishing subsets of the microbial community with a goal to enhance host health. To date, the diversity of polysaccharide compositions in the fiber consumed by humans is not well represented by the limited scope of oligosaccharide compositions present in current commercial prebiotics. Recently, our UC Davis group developed a novel method to generate oligosaccharides from any polysaccharide fiber, termed Fenton's Initiation Toward Defined Oligosaccharide Groups (FITDOG). Using this method, sugar beet pulp (SBP) was transformed into sugar beet oligosaccharides (SBOs) composed of arabinose- and galactose-containing oligosaccharides. Fecal fermentations of SBO and SBP produced similar shifts in donor-specific bacterial communities and acid metabolite profiles with a general enrichment of Bacteroides and Bifidobacterium. However, in vitro tests revealed more Bifidobacterium strains could consume SBO than sugar beet arabinan, and specific strains showed differential consumption of arabinofuranooligosaccharides or galactooligosaccharide (GOS) portions of the SBO pool. Genomic and glycomic comparisons suggest that previously characterized, arabinan-specific, extracellular arabinofuranosidases from Bifidobacterium are not necessary to metabolize the arabino-oligosaccharides within SBO. Synbiotic application of SBO with an SBO-consuming strain Bifidobacterium longum subsp. longum SC596 in serial fecal enrichments resulted in enhanced persistence among 9 of 10 donor feces. This work demonstrates a novel workflow whereby FITDOG creates novel oligosaccharide pools that can provide insight into how compositional differences in fiber drive differential gut fermentation behaviors as well as their downstream health impacts. Moreover, these oligosaccharides may be useful in new prebiotic and synbiotic applications.IMPORTANCEPrebiotics seek to selectively alter the host microbiome composition or function, resulting in a concurrent health benefit to the host. However, commercial prebiotics represent a small fraction of the diversity of food polysaccharide compositions. In this work a novel method, Fenton's Initiation Toward Defined Oligosaccharide Groups (FITDOG) was used to generate an oligosaccharide pool from sugar beet pulp (SBP). Sugar beet oligosaccharides (SBOs) resulted in similar changes to SBP in fecal enrichments; however, SBO could be consumed by more beneficial bifidobacterial strains than the cognate polysaccharide. These results demonstrate how the details of glycan structure have a profound influence on how gut bacteria metabolize food carbohydrates. The implications of this work are relevant to understanding how different dietary sources influence the human microbiome and extend to developing novel oligosaccharide pools for prebiotic applications.
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