About

Razima Chowdhury is a Senior Lecturer in the Department of Asian Studies at Cornell University. She received her B.A. in English Literature & Language and her M.A. in Applied Linguistics and English Language Teaching from the University of Dhaka in Bangladesh. Additionally, she earned an M.A. in Teaching English to Speakers of Other Languages (TESOL) from the Institute of Education, University College London, as a Centenary Scholar. Her research focus involves developing programs for Bangla as a foreign language, leveraging her ESL training and teaching experience. Razima has contributed to language education through teaching, administration, and program development for Bangla in both Bangladesh and the USA. She taught Bangla at Syracuse University via videoconferencing as a Fulbright Foreign Language Teaching Assistant. She also served as the Institute Director for the Critical Language Scholarship Program and developed intensive immersion language programs for Bangla in Dhaka, Bangladesh, during academic year-long programs for various prestigious awards from 2010 to 2016. From 2016 to 2019, she was the Pedagogy Coordinator for Less Commonly Taught Languages at the South Asia Summer Language Institute at the University of Wisconsin-Madison. Her work emphasizes language pedagogy and program development for Bangla, contributing significantly to the field of language education and Asian studies.

Research topics

• Biology
• Chemistry
• Microbiology
• Materials science
• Chemical engineering

Selected publications

• Salmonella exploits a quorum-sensing signal of the gut commensal Stenotrophomonas maltophilia to facilitate its colonization

  Mendeley Data · 2026-03-25

  datasetOpen access1st authorCorresponding

  Raw data for the manuscript: Salmonella exploits a quorum-sensing signal of the gut commensal Stenotrophomonas maltophilia to facilitate its colonization.

  PublisherDOI

• Salmonella exploits a quorum-sensing signal of the gut commensal Stenotrophomonas maltophilia to facilitate its colonization

  Mendeley Data · 2026-03-25

  datasetOpen access1st authorCorresponding

  Raw data for the manuscript: Salmonella exploits a quorum-sensing signal of the gut commensal Stenotrophomonas maltophilia to facilitate its colonization.

  PublisherDOI

• Encapsulation of Essential Oil-Cyclodextrin Inclusion Complexes in Electrospun Pullulan Nanofibers: Enhanced Storage Stability and Antibacterial Property for Geraniol and Linalool

  Food and Bioprocess Technology · 2024-07-25 · 8 citations

  article
  PublisherDOI

• Functionalization of cotton nonwoven with cyclodextrin/lawsone inclusion complex nanofibrous coating for antibacterial wound dressing

  International Journal of Pharmaceutics · 2024-01-17 · 20 citations

  article
  PublisherDOI

• Antibacterial, Anti-Inflammatory, and Antioxidant Cotton-Based Wound Dressing Coated with Chitosan/Cyclodextrin–Quercetin Inclusion Complex Nanofibers

  ACS Applied Bio Materials · 2024-08-04 · 19 citations

  article

  Quercetin, recognized for its antioxidant, anti-inflammatory, and antibacterial properties, faces limited biomedical application due to its low solubility. Cotton, a preferred wound dressing material over synthetic ones, lacks inherent antibacterial and wound-healing attributes and can benefit from quercetin features. This study explores the potential of overcoming these challenges through the inclusion complexation of quercetin with cyclodextrins (CDs) and the development of a nanofibrous coating on a cotton nonwoven textile. Hydroxypropyl-beta-cyclodextrin (HP-β-CD) and hydroxypropyl-gamma-cyclodextrin (HP-γ-CD) formed inclusion complexes of quercetin, with chitosan added to enhance antibacterial properties. Phase solubility results showed that inclusion complexation can enhance quercetin solubility up to 20 times, with HP-γ-CD forming a more stable inclusion complexation compared with HP-β-CD. Electrospinning of the nanofibers from HP-β-CD/Quercetin and HP-γ-CD/Quercetin aqueous solutions without the use of a polymeric matrix yielded a uniform, smooth fiber morphology. The structural and thermal analyses of the HP-β-CD/Quercetin and HP-γ-CD/Quercetin nanofibers confirmed the presence of inclusion complexes between quercetin and each of the CDs (HP-β-CD and HP-γ-CD). Moreover, HP-β-CD/Quercetin and HP-γ-CD/Quercetin nanofibers showed a near-complete loading efficiency of quercetin and followed a fast-releasing profile of quercetin. Both HP-β-CD/Quercetin and HP-γ-CD/Quercetin nanofibers showed significantly higher antioxidant activity compared to pristine quercetin. The HP-β-CD/Quercetin and HP-γ-CD/Quercetin nanofibers also showed antibacterial activity, and with the addition of chitosan in the HP-γ-CD/Quercetin system, the Chitosan/HP-γ-CD/Quercetin nanofibers completely eliminated the investigated bacteria species. The nanofibers were nontoxic and well-tolerated by cells, and exploiting the quercetin and chitosan anti-inflammatory activities resulted in the downregulation of IL-6 and NO secretion in both immune as well as regenerative cells. Overall, CD inclusion complexation markedly enhances quercetin solubility, resulting in a biofunctional antioxidant, antibacterial, and anti-inflammatory wound dressing through a nanofibrous coating on cotton textiles.

  PublisherDOI

• Salmonella Invasion Is Controlled by Competition among Intestinal Chemical Signals

  mBio · 2023-04-05 · 17 citations

  articleOpen access1st authorCorresponding

  Enteric pathogens acutely sense their environment for signals to regulate their virulence functions. We demonstrate here that the enteric pathogen Salmonella utilizes the competition among certain regional intestinal constituents to modulate its virulence determinants in that region. We show that the high concentration of formic acid in the ileum outcompetes other signals and triggers the activation of virulence genes in the ileum. This study shows a delicate spatial and temporal mechanism by which enteric pathogens may utilize the competition among environmental cues to optimize their pathogenicity.

  PublisherDOI

• Recombinant production of a diffusible signal factor inhibits <i>Salmonella</i> invasion and animal carriage

  Gut Microbes · 2023-05-09 · 4 citations

  articleOpen access

  The complex chemical environment of the intestine is defined largely by the metabolic products of the resident microbiota. Enteric pathogens, elegantly evolved to thrive in the gut, use these chemical products as signals to recognize specific niches and to promote their survival and virulence. Our previous work has shown that a specific class of quorum-sensing molecules found within the gut, termed diffusible signal factors (DSF), signals the repression of Salmonella tissue invasion, thus defining a means by which this pathogen recognizes its location and modulates virulence to optimize its survival. Here, we determined whether the recombinant production of a DSF could reduce Salmonella virulence in vitro and in vivo. We found that the most potent repressor of Salmonella invasion, cis-2-hexadecenoic acid (c2-HDA), could be recombinantly produced in E. coli by the addition of a single exogenous gene encoding a fatty acid enoyl-CoA dehydratase/thioesterase and that co-culture of the recombinant strain with Salmonella potently inhibited tissue invasion by repressing Salmonella genes required for this essential virulence function. Using the well characterized E. coli Nissle 1917 strain and a chicken infection model, we found that the recombinant DSF-producing strain could be stably maintained in the large intestine. Further, challenge studies demonstrated that this recombinant organism could significantly reduce Salmonella colonization of the cecum, the site of carriage in this animal species. These findings thus describe a plausible means by which Salmonella virulence may be affected in animals by in situ chemical manipulation of functions essential for colonization and virulence.

  PublisherOA PDFDOI

• Carvacrol/cyclodextrin inclusion complex loaded gelatin/pullulan nanofibers for active food packaging applications

  Food Hydrocolloids · 2023-05-08 · 91 citations

  articleOpen access
  PublisherOA PDFDOI

• Antibacterial Nanofibrous Mat of Pullulan/Cinnamaldehyde-Cyclodextrin Inclusion Complexes as a Potential Cloth Mask Layer with Long-Term Storage Stability and Facile Disposal Property

  ACS Sustainable Chemistry & Engineering · 2023-07-18 · 7 citations

  article

  There is an ongoing rise in global plastic waste because of the mass production and vast consumption of surgical face masks during the COVID-19 outbreak. This problem leads to a crucial need for alternative face coverings which can eliminate environmental concerns. Using cloth masks can be a sustainable solution if combined with a functional filtering layer. In this study, electrospun nanofibrous mats (NM) were generated using a renewable biopolymer; pullulan by the incorporation of cyclodextrin inclusion complexes (γCD-IC) of naturally occurring essential oil compound; trans-cinnamaldehyde (CAH). Pullulan/CAH-γCD-IC NM was readily inserted into a cloth mask due to its free-standing and foldable features and achieved higher loading efficiency (∼62%) than pullulan/CAH NM (∼10%). Here, pullulan/CAH-γCD-IC NM showed substantial and better antibacterial activity, long-term storage stability, and thermal stability due to inclusion complexation. Pullulan/CAH-γCD-IC NM was also obtained with promising properties of pore size (∼390 nm) and water vapor permeability (∼890 g/m2/day). The water solubility of pullulan/CAH-γCD-IC NM ensured fast and easy disposal without potential environmental loading, thanks to the biocompatibility of components. Briefly, pullulan/CAH-γCD-IC NM can create an attractive alternative as a functional layer that can be combined with the cloth mask.

  PublisherDOI

• <i>Shigella flexneri</i> utilizes intestinal signals to control its virulence

  Gut Microbes · 2023-09-23 · 11 citations

  articleOpen access1st authorCorresponding

  to maximize the pathogenic benefit.

  PublisherOA PDFDOI

Frequent coauthors

• Craig Altier

  New York State College of Veterinary Medicine

  39 shared

• Tamer Uyar

  New York State University College of Human Ecology

  24 shared

• Aslı Çelebioğlu

  New York State University College of Human Ecology

  16 shared

• Paulina D. Pavinski Bitar

  Cornell University

  15 shared

• Mahmoud Aboelkheir

  New York State University College of Human Ecology

  12 shared

• Emmy Hsiung

  New York State University College of Human Ecology

  12 shared

• Kübra Ertan

  Middle East Technical University

  8 shared

• Mohsen Alishahi

  New York State University College of Human Ecology

  8 shared

Awards & honors

• Selden Memorial Translation Prize